git.oblomov.eu Git - git/blob - apply.c

   1 /*
   2  * apply.c
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  *
   6  * This applies patches on top of some (arbitrary) version of the SCM.
   7  *
   8  */
   9
  10 #include "cache.h"
  11 #include "config.h"
  12 #include "blob.h"
  13 #include "delta.h"
  14 #include "diff.h"
  15 #include "dir.h"
  16 #include "xdiff-interface.h"
  17 #include "ll-merge.h"
  18 #include "lockfile.h"
  19 #include "parse-options.h"
  20 #include "quote.h"
  21 #include "rerere.h"
  22 #include "apply.h"
  23
  24 static void git_apply_config(void)
  25 {
  26         git_config_get_string_const("apply.whitespace", &apply_default_whitespace);
  27         git_config_get_string_const("apply.ignorewhitespace", &apply_default_ignorewhitespace);
  28         git_config(git_default_config, NULL);
  29 }
  30
  31 static int parse_whitespace_option(struct apply_state *state, const char *option)
  32 {
  33         if (!option) {
  34                 state->ws_error_action = warn_on_ws_error;
  35                 return 0;
  36         }
  37         if (!strcmp(option, "warn")) {
  38                 state->ws_error_action = warn_on_ws_error;
  39                 return 0;
  40         }
  41         if (!strcmp(option, "nowarn")) {
  42                 state->ws_error_action = nowarn_ws_error;
  43                 return 0;
  44         }
  45         if (!strcmp(option, "error")) {
  46                 state->ws_error_action = die_on_ws_error;
  47                 return 0;
  48         }
  49         if (!strcmp(option, "error-all")) {
  50                 state->ws_error_action = die_on_ws_error;
  51                 state->squelch_whitespace_errors = 0;
  52                 return 0;
  53         }
  54         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
  55                 state->ws_error_action = correct_ws_error;
  56                 return 0;
  57         }
  58         return error(_("unrecognized whitespace option '%s'"), option);
  59 }
  60
  61 static int parse_ignorewhitespace_option(struct apply_state *state,
  62                                                  const char *option)
  63 {
  64         if (!option || !strcmp(option, "no") ||
  65             !strcmp(option, "false") || !strcmp(option, "never") ||
  66             !strcmp(option, "none")) {
  67                 state->ws_ignore_action = ignore_ws_none;
  68                 return 0;
  69         }
  70         if (!strcmp(option, "change")) {
  71                 state->ws_ignore_action = ignore_ws_change;
  72                 return 0;
  73         }
  74         return error(_("unrecognized whitespace ignore option '%s'"), option);
  75 }
  76
  77 int init_apply_state(struct apply_state *state,
  78                      const char *prefix)
  79 {
  80         memset(state, 0, sizeof(*state));
  81         state->prefix = prefix;
  82         state->apply = 1;
  83         state->line_termination = '\n';
  84         state->p_value = 1;
  85         state->p_context = UINT_MAX;
  86         state->squelch_whitespace_errors = 5;
  87         state->ws_error_action = warn_on_ws_error;
  88         state->ws_ignore_action = ignore_ws_none;
  89         state->linenr = 1;
  90         string_list_init(&state->fn_table, 0);
  91         string_list_init(&state->limit_by_name, 0);
  92         string_list_init(&state->symlink_changes, 0);
  93         strbuf_init(&state->root, 0);
  94
  95         git_apply_config();
  96         if (apply_default_whitespace && parse_whitespace_option(state, apply_default_whitespace))
  97                 return -1;
  98         if (apply_default_ignorewhitespace && parse_ignorewhitespace_option(state, apply_default_ignorewhitespace))
  99                 return -1;
 100         return 0;
 101 }
 102
 103 void clear_apply_state(struct apply_state *state)
 104 {
 105         string_list_clear(&state->limit_by_name, 0);
 106         string_list_clear(&state->symlink_changes, 0);
 107         strbuf_release(&state->root);
 108
 109         /* &state->fn_table is cleared at the end of apply_patch() */
 110 }
 111
 112 static void mute_routine(const char *msg, va_list params)
 113 {
 114         /* do nothing */
 115 }
 116
 117 int check_apply_state(struct apply_state *state, int force_apply)
 118 {
 119         int is_not_gitdir = !startup_info->have_repository;
 120
 121         if (state->apply_with_reject && state->threeway)
 122                 return error(_("--reject and --3way cannot be used together."));
 123         if (state->cached && state->threeway)
 124                 return error(_("--cached and --3way cannot be used together."));
 125         if (state->threeway) {
 126                 if (is_not_gitdir)
 127                         return error(_("--3way outside a repository"));
 128                 state->check_index = 1;
 129         }
 130         if (state->apply_with_reject) {
 131                 state->apply = 1;
 132                 if (state->apply_verbosity == verbosity_normal)
 133                         state->apply_verbosity = verbosity_verbose;
 134         }
 135         if (!force_apply && (state->diffstat || state->numstat || state->summary || state->check || state->fake_ancestor))
 136                 state->apply = 0;
 137         if (state->check_index && is_not_gitdir)
 138                 return error(_("--index outside a repository"));
 139         if (state->cached) {
 140                 if (is_not_gitdir)
 141                         return error(_("--cached outside a repository"));
 142                 state->check_index = 1;
 143         }
 144         if (state->check_index)
 145                 state->unsafe_paths = 0;
 146
 147         if (state->apply_verbosity <= verbosity_silent) {
 148                 state->saved_error_routine = get_error_routine();
 149                 state->saved_warn_routine = get_warn_routine();
 150                 set_error_routine(mute_routine);
 151                 set_warn_routine(mute_routine);
 152         }
 153
 154         return 0;
 155 }
 156
 157 static void set_default_whitespace_mode(struct apply_state *state)
 158 {
 159         if (!state->whitespace_option && !apply_default_whitespace)
 160                 state->ws_error_action = (state->apply ? warn_on_ws_error : nowarn_ws_error);
 161 }
 162
 163 /*
 164  * This represents one "hunk" from a patch, starting with
 165  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 166  * patch text is pointed at by patch, and its byte length
 167  * is stored in size.  leading and trailing are the number
 168  * of context lines.
 169  */
 170 struct fragment {
 171         unsigned long leading, trailing;
 172         unsigned long oldpos, oldlines;
 173         unsigned long newpos, newlines;
 174         /*
 175          * 'patch' is usually borrowed from buf in apply_patch(),
 176          * but some codepaths store an allocated buffer.
 177          */
 178         const char *patch;
 179         unsigned free_patch:1,
 180                 rejected:1;
 181         int size;
 182         int linenr;
 183         struct fragment *next;
 184 };
 185
 186 /*
 187  * When dealing with a binary patch, we reuse "leading" field
 188  * to store the type of the binary hunk, either deflated "delta"
 189  * or deflated "literal".
 190  */
 191 #define binary_patch_method leading
 192 #define BINARY_DELTA_DEFLATED   1
 193 #define BINARY_LITERAL_DEFLATED 2
 194
 195 /*
 196  * This represents a "patch" to a file, both metainfo changes
 197  * such as creation/deletion, filemode and content changes represented
 198  * as a series of fragments.
 199  */
 200 struct patch {
 201         char *new_name, *old_name, *def_name;
 202         unsigned int old_mode, new_mode;
 203         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
 204         int rejected;
 205         unsigned ws_rule;
 206         int lines_added, lines_deleted;
 207         int score;
 208         int extension_linenr; /* first line specifying delete/new/rename/copy */
 209         unsigned int is_toplevel_relative:1;
 210         unsigned int inaccurate_eof:1;
 211         unsigned int is_binary:1;
 212         unsigned int is_copy:1;
 213         unsigned int is_rename:1;
 214         unsigned int recount:1;
 215         unsigned int conflicted_threeway:1;
 216         unsigned int direct_to_threeway:1;
 217         unsigned int crlf_in_old:1;
 218         struct fragment *fragments;
 219         char *result;
 220         size_t resultsize;
 221         char old_sha1_prefix[41];
 222         char new_sha1_prefix[41];
 223         struct patch *next;
 224
 225         /* three-way fallback result */
 226         struct object_id threeway_stage[3];
 227 };
 228
 229 static void free_fragment_list(struct fragment *list)
 230 {
 231         while (list) {
 232                 struct fragment *next = list->next;
 233                 if (list->free_patch)
 234                         free((char *)list->patch);
 235                 free(list);
 236                 list = next;
 237         }
 238 }
 239
 240 static void free_patch(struct patch *patch)
 241 {
 242         free_fragment_list(patch->fragments);
 243         free(patch->def_name);
 244         free(patch->old_name);
 245         free(patch->new_name);
 246         free(patch->result);
 247         free(patch);
 248 }
 249
 250 static void free_patch_list(struct patch *list)
 251 {
 252         while (list) {
 253                 struct patch *next = list->next;
 254                 free_patch(list);
 255                 list = next;
 256         }
 257 }
 258
 259 /*
 260  * A line in a file, len-bytes long (includes the terminating LF,
 261  * except for an incomplete line at the end if the file ends with
 262  * one), and its contents hashes to 'hash'.
 263  */
 264 struct line {
 265         size_t len;
 266         unsigned hash : 24;
 267         unsigned flag : 8;
 268 #define LINE_COMMON     1
 269 #define LINE_PATCHED    2
 270 };
 271
 272 /*
 273  * This represents a "file", which is an array of "lines".
 274  */
 275 struct image {
 276         char *buf;
 277         size_t len;
 278         size_t nr;
 279         size_t alloc;
 280         struct line *line_allocated;
 281         struct line *line;
 282 };
 283
 284 static uint32_t hash_line(const char *cp, size_t len)
 285 {
 286         size_t i;
 287         uint32_t h;
 288         for (i = 0, h = 0; i < len; i++) {
 289                 if (!isspace(cp[i])) {
 290                         h = h * 3 + (cp[i] & 0xff);
 291                 }
 292         }
 293         return h;
 294 }
 295
 296 /*
 297  * Compare lines s1 of length n1 and s2 of length n2, ignoring
 298  * whitespace difference. Returns 1 if they match, 0 otherwise
 299  */
 300 static int fuzzy_matchlines(const char *s1, size_t n1,
 301                             const char *s2, size_t n2)
 302 {
 303         const char *last1 = s1 + n1 - 1;
 304         const char *last2 = s2 + n2 - 1;
 305         int result = 0;
 306
 307         /* ignore line endings */
 308         while ((*last1 == '\r') || (*last1 == '\n'))
 309                 last1--;
 310         while ((*last2 == '\r') || (*last2 == '\n'))
 311                 last2--;
 312
 313         /* skip leading whitespaces, if both begin with whitespace */
 314         if (s1 <= last1 && s2 <= last2 && isspace(*s1) && isspace(*s2)) {
 315                 while (isspace(*s1) && (s1 <= last1))
 316                         s1++;
 317                 while (isspace(*s2) && (s2 <= last2))
 318                         s2++;
 319         }
 320         /* early return if both lines are empty */
 321         if ((s1 > last1) && (s2 > last2))
 322                 return 1;
 323         while (!result) {
 324                 result = *s1++ - *s2++;
 325                 /*
 326                  * Skip whitespace inside. We check for whitespace on
 327                  * both buffers because we don't want "a b" to match
 328                  * "ab"
 329                  */
 330                 if (isspace(*s1) && isspace(*s2)) {
 331                         while (isspace(*s1) && s1 <= last1)
 332                                 s1++;
 333                         while (isspace(*s2) && s2 <= last2)
 334                                 s2++;
 335                 }
 336                 /*
 337                  * If we reached the end on one side only,
 338                  * lines don't match
 339                  */
 340                 if (
 341                     ((s2 > last2) && (s1 <= last1)) ||
 342                     ((s1 > last1) && (s2 <= last2)))
 343                         return 0;
 344                 if ((s1 > last1) && (s2 > last2))
 345                         break;
 346         }
 347
 348         return !result;
 349 }
 350
 351 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
 352 {
 353         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
 354         img->line_allocated[img->nr].len = len;
 355         img->line_allocated[img->nr].hash = hash_line(bol, len);
 356         img->line_allocated[img->nr].flag = flag;
 357         img->nr++;
 358 }
 359
 360 /*
 361  * "buf" has the file contents to be patched (read from various sources).
 362  * attach it to "image" and add line-based index to it.
 363  * "image" now owns the "buf".
 364  */
 365 static void prepare_image(struct image *image, char *buf, size_t len,
 366                           int prepare_linetable)
 367 {
 368         const char *cp, *ep;
 369
 370         memset(image, 0, sizeof(*image));
 371         image->buf = buf;
 372         image->len = len;
 373
 374         if (!prepare_linetable)
 375                 return;
 376
 377         ep = image->buf + image->len;
 378         cp = image->buf;
 379         while (cp < ep) {
 380                 const char *next;
 381                 for (next = cp; next < ep && *next != '\n'; next++)
 382                         ;
 383                 if (next < ep)
 384                         next++;
 385                 add_line_info(image, cp, next - cp, 0);
 386                 cp = next;
 387         }
 388         image->line = image->line_allocated;
 389 }
 390
 391 static void clear_image(struct image *image)
 392 {
 393         free(image->buf);
 394         free(image->line_allocated);
 395         memset(image, 0, sizeof(*image));
 396 }
 397
 398 /* fmt must contain _one_ %s and no other substitution */
 399 static void say_patch_name(FILE *output, const char *fmt, struct patch *patch)
 400 {
 401         struct strbuf sb = STRBUF_INIT;
 402
 403         if (patch->old_name && patch->new_name &&
 404             strcmp(patch->old_name, patch->new_name)) {
 405                 quote_c_style(patch->old_name, &sb, NULL, 0);
 406                 strbuf_addstr(&sb, " => ");
 407                 quote_c_style(patch->new_name, &sb, NULL, 0);
 408         } else {
 409                 const char *n = patch->new_name;
 410                 if (!n)
 411                         n = patch->old_name;
 412                 quote_c_style(n, &sb, NULL, 0);
 413         }
 414         fprintf(output, fmt, sb.buf);
 415         fputc('\n', output);
 416         strbuf_release(&sb);
 417 }
 418
 419 #define SLOP (16)
 420
 421 static int read_patch_file(struct strbuf *sb, int fd)
 422 {
 423         if (strbuf_read(sb, fd, 0) < 0)
 424                 return error_errno("git apply: failed to read");
 425
 426         /*
 427          * Make sure that we have some slop in the buffer
 428          * so that we can do speculative "memcmp" etc, and
 429          * see to it that it is NUL-filled.
 430          */
 431         strbuf_grow(sb, SLOP);
 432         memset(sb->buf + sb->len, 0, SLOP);
 433         return 0;
 434 }
 435
 436 static unsigned long linelen(const char *buffer, unsigned long size)
 437 {
 438         unsigned long len = 0;
 439         while (size--) {
 440                 len++;
 441                 if (*buffer++ == '\n')
 442                         break;
 443         }
 444         return len;
 445 }
 446
 447 static int is_dev_null(const char *str)
 448 {
 449         return skip_prefix(str, "/dev/null", &str) && isspace(*str);
 450 }
 451
 452 #define TERM_SPACE      1
 453 #define TERM_TAB        2
 454
 455 static int name_terminate(int c, int terminate)
 456 {
 457         if (c == ' ' && !(terminate & TERM_SPACE))
 458                 return 0;
 459         if (c == '\t' && !(terminate & TERM_TAB))
 460                 return 0;
 461
 462         return 1;
 463 }
 464
 465 /* remove double slashes to make --index work with such filenames */
 466 static char *squash_slash(char *name)
 467 {
 468         int i = 0, j = 0;
 469
 470         if (!name)
 471                 return NULL;
 472
 473         while (name[i]) {
 474                 if ((name[j++] = name[i++]) == '/')
 475                         while (name[i] == '/')
 476                                 i++;
 477         }
 478         name[j] = '\0';
 479         return name;
 480 }
 481
 482 static char *find_name_gnu(struct apply_state *state,
 483                            const char *line,
 484                            const char *def,
 485                            int p_value)
 486 {
 487         struct strbuf name = STRBUF_INIT;
 488         char *cp;
 489
 490         /*
 491          * Proposed "new-style" GNU patch/diff format; see
 492          * http://marc.info/?l=git&m=112927316408690&w=2
 493          */
 494         if (unquote_c_style(&name, line, NULL)) {
 495                 strbuf_release(&name);
 496                 return NULL;
 497         }
 498
 499         for (cp = name.buf; p_value; p_value--) {
 500                 cp = strchr(cp, '/');
 501                 if (!cp) {
 502                         strbuf_release(&name);
 503                         return NULL;
 504                 }
 505                 cp++;
 506         }
 507
 508         strbuf_remove(&name, 0, cp - name.buf);
 509         if (state->root.len)
 510                 strbuf_insert(&name, 0, state->root.buf, state->root.len);
 511         return squash_slash(strbuf_detach(&name, NULL));
 512 }
 513
 514 static size_t sane_tz_len(const char *line, size_t len)
 515 {
 516         const char *tz, *p;
 517
 518         if (len < strlen(" +0500") || line[len-strlen(" +0500")] != ' ')
 519                 return 0;
 520         tz = line + len - strlen(" +0500");
 521
 522         if (tz[1] != '+' && tz[1] != '-')
 523                 return 0;
 524
 525         for (p = tz + 2; p != line + len; p++)
 526                 if (!isdigit(*p))
 527                         return 0;
 528
 529         return line + len - tz;
 530 }
 531
 532 static size_t tz_with_colon_len(const char *line, size_t len)
 533 {
 534         const char *tz, *p;
 535
 536         if (len < strlen(" +08:00") || line[len - strlen(":00")] != ':')
 537                 return 0;
 538         tz = line + len - strlen(" +08:00");
 539
 540         if (tz[0] != ' ' || (tz[1] != '+' && tz[1] != '-'))
 541                 return 0;
 542         p = tz + 2;
 543         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 544             !isdigit(*p++) || !isdigit(*p++))
 545                 return 0;
 546
 547         return line + len - tz;
 548 }
 549
 550 static size_t date_len(const char *line, size_t len)
 551 {
 552         const char *date, *p;
 553
 554         if (len < strlen("72-02-05") || line[len-strlen("-05")] != '-')
 555                 return 0;
 556         p = date = line + len - strlen("72-02-05");
 557
 558         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
 559             !isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
 560             !isdigit(*p++) || !isdigit(*p++))   /* Not a date. */
 561                 return 0;
 562
 563         if (date - line >= strlen("19") &&
 564             isdigit(date[-1]) && isdigit(date[-2]))     /* 4-digit year */
 565                 date -= strlen("19");
 566
 567         return line + len - date;
 568 }
 569
 570 static size_t short_time_len(const char *line, size_t len)
 571 {
 572         const char *time, *p;
 573
 574         if (len < strlen(" 07:01:32") || line[len-strlen(":32")] != ':')
 575                 return 0;
 576         p = time = line + len - strlen(" 07:01:32");
 577
 578         /* Permit 1-digit hours? */
 579         if (*p++ != ' ' ||
 580             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 581             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 582             !isdigit(*p++) || !isdigit(*p++))   /* Not a time. */
 583                 return 0;
 584
 585         return line + len - time;
 586 }
 587
 588 static size_t fractional_time_len(const char *line, size_t len)
 589 {
 590         const char *p;
 591         size_t n;
 592
 593         /* Expected format: 19:41:17.620000023 */
 594         if (!len || !isdigit(line[len - 1]))
 595                 return 0;
 596         p = line + len - 1;
 597
 598         /* Fractional seconds. */
 599         while (p > line && isdigit(*p))
 600                 p--;
 601         if (*p != '.')
 602                 return 0;
 603
 604         /* Hours, minutes, and whole seconds. */
 605         n = short_time_len(line, p - line);
 606         if (!n)
 607                 return 0;
 608
 609         return line + len - p + n;
 610 }
 611
 612 static size_t trailing_spaces_len(const char *line, size_t len)
 613 {
 614         const char *p;
 615
 616         /* Expected format: ' ' x (1 or more)  */
 617         if (!len || line[len - 1] != ' ')
 618                 return 0;
 619
 620         p = line + len;
 621         while (p != line) {
 622                 p--;
 623                 if (*p != ' ')
 624                         return line + len - (p + 1);
 625         }
 626
 627         /* All spaces! */
 628         return len;
 629 }
 630
 631 static size_t diff_timestamp_len(const char *line, size_t len)
 632 {
 633         const char *end = line + len;
 634         size_t n;
 635
 636         /*
 637          * Posix: 2010-07-05 19:41:17
 638          * GNU: 2010-07-05 19:41:17.620000023 -0500
 639          */
 640
 641         if (!isdigit(end[-1]))
 642                 return 0;
 643
 644         n = sane_tz_len(line, end - line);
 645         if (!n)
 646                 n = tz_with_colon_len(line, end - line);
 647         end -= n;
 648
 649         n = short_time_len(line, end - line);
 650         if (!n)
 651                 n = fractional_time_len(line, end - line);
 652         end -= n;
 653
 654         n = date_len(line, end - line);
 655         if (!n) /* No date.  Too bad. */
 656                 return 0;
 657         end -= n;
 658
 659         if (end == line)        /* No space before date. */
 660                 return 0;
 661         if (end[-1] == '\t') {  /* Success! */
 662                 end--;
 663                 return line + len - end;
 664         }
 665         if (end[-1] != ' ')     /* No space before date. */
 666                 return 0;
 667
 668         /* Whitespace damage. */
 669         end -= trailing_spaces_len(line, end - line);
 670         return line + len - end;
 671 }
 672
 673 static char *find_name_common(struct apply_state *state,
 674                               const char *line,
 675                               const char *def,
 676                               int p_value,
 677                               const char *end,
 678                               int terminate)
 679 {
 680         int len;
 681         const char *start = NULL;
 682
 683         if (p_value == 0)
 684                 start = line;
 685         while (line != end) {
 686                 char c = *line;
 687
 688                 if (!end && isspace(c)) {
 689                         if (c == '\n')
 690                                 break;
 691                         if (name_terminate(c, terminate))
 692                                 break;
 693                 }
 694                 line++;
 695                 if (c == '/' && !--p_value)
 696                         start = line;
 697         }
 698         if (!start)
 699                 return squash_slash(xstrdup_or_null(def));
 700         len = line - start;
 701         if (!len)
 702                 return squash_slash(xstrdup_or_null(def));
 703
 704         /*
 705          * Generally we prefer the shorter name, especially
 706          * if the other one is just a variation of that with
 707          * something else tacked on to the end (ie "file.orig"
 708          * or "file~").
 709          */
 710         if (def) {
 711                 int deflen = strlen(def);
 712                 if (deflen < len && !strncmp(start, def, deflen))
 713                         return squash_slash(xstrdup(def));
 714         }
 715
 716         if (state->root.len) {
 717                 char *ret = xstrfmt("%s%.*s", state->root.buf, len, start);
 718                 return squash_slash(ret);
 719         }
 720
 721         return squash_slash(xmemdupz(start, len));
 722 }
 723
 724 static char *find_name(struct apply_state *state,
 725                        const char *line,
 726                        char *def,
 727                        int p_value,
 728                        int terminate)
 729 {
 730         if (*line == '"') {
 731                 char *name = find_name_gnu(state, line, def, p_value);
 732                 if (name)
 733                         return name;
 734         }
 735
 736         return find_name_common(state, line, def, p_value, NULL, terminate);
 737 }
 738
 739 static char *find_name_traditional(struct apply_state *state,
 740                                    const char *line,
 741                                    char *def,
 742                                    int p_value)
 743 {
 744         size_t len;
 745         size_t date_len;
 746
 747         if (*line == '"') {
 748                 char *name = find_name_gnu(state, line, def, p_value);
 749                 if (name)
 750                         return name;
 751         }
 752
 753         len = strchrnul(line, '\n') - line;
 754         date_len = diff_timestamp_len(line, len);
 755         if (!date_len)
 756                 return find_name_common(state, line, def, p_value, NULL, TERM_TAB);
 757         len -= date_len;
 758
 759         return find_name_common(state, line, def, p_value, line + len, 0);
 760 }
 761
 762 /*
 763  * Given the string after "--- " or "+++ ", guess the appropriate
 764  * p_value for the given patch.
 765  */
 766 static int guess_p_value(struct apply_state *state, const char *nameline)
 767 {
 768         char *name, *cp;
 769         int val = -1;
 770
 771         if (is_dev_null(nameline))
 772                 return -1;
 773         name = find_name_traditional(state, nameline, NULL, 0);
 774         if (!name)
 775                 return -1;
 776         cp = strchr(name, '/');
 777         if (!cp)
 778                 val = 0;
 779         else if (state->prefix) {
 780                 /*
 781                  * Does it begin with "a/$our-prefix" and such?  Then this is
 782                  * very likely to apply to our directory.
 783                  */
 784                 if (starts_with(name, state->prefix))
 785                         val = count_slashes(state->prefix);
 786                 else {
 787                         cp++;
 788                         if (starts_with(cp, state->prefix))
 789                                 val = count_slashes(state->prefix) + 1;
 790                 }
 791         }
 792         free(name);
 793         return val;
 794 }
 795
 796 /*
 797  * Does the ---/+++ line have the POSIX timestamp after the last HT?
 798  * GNU diff puts epoch there to signal a creation/deletion event.  Is
 799  * this such a timestamp?
 800  */
 801 static int has_epoch_timestamp(const char *nameline)
 802 {
 803         /*
 804          * We are only interested in epoch timestamp; any non-zero
 805          * fraction cannot be one, hence "(\.0+)?" in the regexp below.
 806          * For the same reason, the date must be either 1969-12-31 or
 807          * 1970-01-01, and the seconds part must be "00".
 808          */
 809         const char stamp_regexp[] =
 810                 "^[0-2][0-9]:([0-5][0-9]):00(\\.0+)?"
 811                 " "
 812                 "([-+][0-2][0-9]:?[0-5][0-9])\n";
 813         const char *timestamp = NULL, *cp, *colon;
 814         static regex_t *stamp;
 815         regmatch_t m[10];
 816         int zoneoffset, epoch_hour, hour, minute;
 817         int status;
 818
 819         for (cp = nameline; *cp != '\n'; cp++) {
 820                 if (*cp == '\t')
 821                         timestamp = cp + 1;
 822         }
 823         if (!timestamp)
 824                 return 0;
 825
 826         /*
 827          * YYYY-MM-DD hh:mm:ss must be from either 1969-12-31
 828          * (west of GMT) or 1970-01-01 (east of GMT)
 829          */
 830         if (skip_prefix(timestamp, "1969-12-31 ", &timestamp))
 831                 epoch_hour = 24;
 832         else if (skip_prefix(timestamp, "1970-01-01 ", &timestamp))
 833                 epoch_hour = 0;
 834         else
 835                 return 0;
 836
 837         if (!stamp) {
 838                 stamp = xmalloc(sizeof(*stamp));
 839                 if (regcomp(stamp, stamp_regexp, REG_EXTENDED)) {
 840                         warning(_("Cannot prepare timestamp regexp %s"),
 841                                 stamp_regexp);
 842                         return 0;
 843                 }
 844         }
 845
 846         status = regexec(stamp, timestamp, ARRAY_SIZE(m), m, 0);
 847         if (status) {
 848                 if (status != REG_NOMATCH)
 849                         warning(_("regexec returned %d for input: %s"),
 850                                 status, timestamp);
 851                 return 0;
 852         }
 853
 854         hour = strtol(timestamp, NULL, 10);
 855         minute = strtol(timestamp + m[1].rm_so, NULL, 10);
 856
 857         zoneoffset = strtol(timestamp + m[3].rm_so + 1, (char **) &colon, 10);
 858         if (*colon == ':')
 859                 zoneoffset = zoneoffset * 60 + strtol(colon + 1, NULL, 10);
 860         else
 861                 zoneoffset = (zoneoffset / 100) * 60 + (zoneoffset % 100);
 862         if (timestamp[m[3].rm_so] == '-')
 863                 zoneoffset = -zoneoffset;
 864
 865         return hour * 60 + minute - zoneoffset == epoch_hour * 60;
 866 }
 867
 868 /*
 869  * Get the name etc info from the ---/+++ lines of a traditional patch header
 870  *
 871  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 872  * files, we can happily check the index for a match, but for creating a
 873  * new file we should try to match whatever "patch" does. I have no idea.
 874  */
 875 static int parse_traditional_patch(struct apply_state *state,
 876                                    const char *first,
 877                                    const char *second,
 878                                    struct patch *patch)
 879 {
 880         char *name;
 881
 882         first += 4;     /* skip "--- " */
 883         second += 4;    /* skip "+++ " */
 884         if (!state->p_value_known) {
 885                 int p, q;
 886                 p = guess_p_value(state, first);
 887                 q = guess_p_value(state, second);
 888                 if (p < 0) p = q;
 889                 if (0 <= p && p == q) {
 890                         state->p_value = p;
 891                         state->p_value_known = 1;
 892                 }
 893         }
 894         if (is_dev_null(first)) {
 895                 patch->is_new = 1;
 896                 patch->is_delete = 0;
 897                 name = find_name_traditional(state, second, NULL, state->p_value);
 898                 patch->new_name = name;
 899         } else if (is_dev_null(second)) {
 900                 patch->is_new = 0;
 901                 patch->is_delete = 1;
 902                 name = find_name_traditional(state, first, NULL, state->p_value);
 903                 patch->old_name = name;
 904         } else {
 905                 char *first_name;
 906                 first_name = find_name_traditional(state, first, NULL, state->p_value);
 907                 name = find_name_traditional(state, second, first_name, state->p_value);
 908                 free(first_name);
 909                 if (has_epoch_timestamp(first)) {
 910                         patch->is_new = 1;
 911                         patch->is_delete = 0;
 912                         patch->new_name = name;
 913                 } else if (has_epoch_timestamp(second)) {
 914                         patch->is_new = 0;
 915                         patch->is_delete = 1;
 916                         patch->old_name = name;
 917                 } else {
 918                         patch->old_name = name;
 919                         patch->new_name = xstrdup_or_null(name);
 920                 }
 921         }
 922         if (!name)
 923                 return error(_("unable to find filename in patch at line %d"), state->linenr);
 924
 925         return 0;
 926 }
 927
 928 static int gitdiff_hdrend(struct apply_state *state,
 929                           const char *line,
 930                           struct patch *patch)
 931 {
 932         return 1;
 933 }
 934
 935 /*
 936  * We're anal about diff header consistency, to make
 937  * sure that we don't end up having strange ambiguous
 938  * patches floating around.
 939  *
 940  * As a result, gitdiff_{old|new}name() will check
 941  * their names against any previous information, just
 942  * to make sure..
 943  */
 944 #define DIFF_OLD_NAME 0
 945 #define DIFF_NEW_NAME 1
 946
 947 static int gitdiff_verify_name(struct apply_state *state,
 948                                const char *line,
 949                                int isnull,
 950                                char **name,
 951                                int side)
 952 {
 953         if (!*name && !isnull) {
 954                 *name = find_name(state, line, NULL, state->p_value, TERM_TAB);
 955                 return 0;
 956         }
 957
 958         if (*name) {
 959                 char *another;
 960                 if (isnull)
 961                         return error(_("git apply: bad git-diff - expected /dev/null, got %s on line %d"),
 962                                      *name, state->linenr);
 963                 another = find_name(state, line, NULL, state->p_value, TERM_TAB);
 964                 if (!another || strcmp(another, *name)) {
 965                         free(another);
 966                         return error((side == DIFF_NEW_NAME) ?
 967                             _("git apply: bad git-diff - inconsistent new filename on line %d") :
 968                             _("git apply: bad git-diff - inconsistent old filename on line %d"), state->linenr);
 969                 }
 970                 free(another);
 971         } else {
 972                 if (!starts_with(line, "/dev/null\n"))
 973                         return error(_("git apply: bad git-diff - expected /dev/null on line %d"), state->linenr);
 974         }
 975
 976         return 0;
 977 }
 978
 979 static int gitdiff_oldname(struct apply_state *state,
 980                            const char *line,
 981                            struct patch *patch)
 982 {
 983         return gitdiff_verify_name(state, line,
 984                                    patch->is_new, &patch->old_name,
 985                                    DIFF_OLD_NAME);
 986 }
 987
 988 static int gitdiff_newname(struct apply_state *state,
 989                            const char *line,
 990                            struct patch *patch)
 991 {
 992         return gitdiff_verify_name(state, line,
 993                                    patch->is_delete, &patch->new_name,
 994                                    DIFF_NEW_NAME);
 995 }
 996
 997 static int parse_mode_line(const char *line, int linenr, unsigned int *mode)
 998 {
 999         char *end;
1000         *mode = strtoul(line, &end, 8);
1001         if (end == line || !isspace(*end))
1002                 return error(_("invalid mode on line %d: %s"), linenr, line);
1003         return 0;
1004 }
1005
1006 static int gitdiff_oldmode(struct apply_state *state,
1007                            const char *line,
1008                            struct patch *patch)
1009 {
1010         return parse_mode_line(line, state->linenr, &patch->old_mode);
1011 }
1012
1013 static int gitdiff_newmode(struct apply_state *state,
1014                            const char *line,
1015                            struct patch *patch)
1016 {
1017         return parse_mode_line(line, state->linenr, &patch->new_mode);
1018 }
1019
1020 static int gitdiff_delete(struct apply_state *state,
1021                           const char *line,
1022                           struct patch *patch)
1023 {
1024         patch->is_delete = 1;
1025         free(patch->old_name);
1026         patch->old_name = xstrdup_or_null(patch->def_name);
1027         return gitdiff_oldmode(state, line, patch);
1028 }
1029
1030 static int gitdiff_newfile(struct apply_state *state,
1031                            const char *line,
1032                            struct patch *patch)
1033 {
1034         patch->is_new = 1;
1035         free(patch->new_name);
1036         patch->new_name = xstrdup_or_null(patch->def_name);
1037         return gitdiff_newmode(state, line, patch);
1038 }
1039
1040 static int gitdiff_copysrc(struct apply_state *state,
1041                            const char *line,
1042                            struct patch *patch)
1043 {
1044         patch->is_copy = 1;
1045         free(patch->old_name);
1046         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1047         return 0;
1048 }
1049
1050 static int gitdiff_copydst(struct apply_state *state,
1051                            const char *line,
1052                            struct patch *patch)
1053 {
1054         patch->is_copy = 1;
1055         free(patch->new_name);
1056         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1057         return 0;
1058 }
1059
1060 static int gitdiff_renamesrc(struct apply_state *state,
1061                              const char *line,
1062                              struct patch *patch)
1063 {
1064         patch->is_rename = 1;
1065         free(patch->old_name);
1066         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1067         return 0;
1068 }
1069
1070 static int gitdiff_renamedst(struct apply_state *state,
1071                              const char *line,
1072                              struct patch *patch)
1073 {
1074         patch->is_rename = 1;
1075         free(patch->new_name);
1076         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1077         return 0;
1078 }
1079
1080 static int gitdiff_similarity(struct apply_state *state,
1081                               const char *line,
1082                               struct patch *patch)
1083 {
1084         unsigned long val = strtoul(line, NULL, 10);
1085         if (val <= 100)
1086                 patch->score = val;
1087         return 0;
1088 }
1089
1090 static int gitdiff_dissimilarity(struct apply_state *state,
1091                                  const char *line,
1092                                  struct patch *patch)
1093 {
1094         unsigned long val = strtoul(line, NULL, 10);
1095         if (val <= 100)
1096                 patch->score = val;
1097         return 0;
1098 }
1099
1100 static int gitdiff_index(struct apply_state *state,
1101                          const char *line,
1102                          struct patch *patch)
1103 {
1104         /*
1105          * index line is N hexadecimal, "..", N hexadecimal,
1106          * and optional space with octal mode.
1107          */
1108         const char *ptr, *eol;
1109         int len;
1110
1111         ptr = strchr(line, '.');
1112         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
1113                 return 0;
1114         len = ptr - line;
1115         memcpy(patch->old_sha1_prefix, line, len);
1116         patch->old_sha1_prefix[len] = 0;
1117
1118         line = ptr + 2;
1119         ptr = strchr(line, ' ');
1120         eol = strchrnul(line, '\n');
1121
1122         if (!ptr || eol < ptr)
1123                 ptr = eol;
1124         len = ptr - line;
1125
1126         if (40 < len)
1127                 return 0;
1128         memcpy(patch->new_sha1_prefix, line, len);
1129         patch->new_sha1_prefix[len] = 0;
1130         if (*ptr == ' ')
1131                 return gitdiff_oldmode(state, ptr + 1, patch);
1132         return 0;
1133 }
1134
1135 /*
1136  * This is normal for a diff that doesn't change anything: we'll fall through
1137  * into the next diff. Tell the parser to break out.
1138  */
1139 static int gitdiff_unrecognized(struct apply_state *state,
1140                                 const char *line,
1141                                 struct patch *patch)
1142 {
1143         return 1;
1144 }
1145
1146 /*
1147  * Skip p_value leading components from "line"; as we do not accept
1148  * absolute paths, return NULL in that case.
1149  */
1150 static const char *skip_tree_prefix(struct apply_state *state,
1151                                     const char *line,
1152                                     int llen)
1153 {
1154         int nslash;
1155         int i;
1156
1157         if (!state->p_value)
1158                 return (llen && line[0] == '/') ? NULL : line;
1159
1160         nslash = state->p_value;
1161         for (i = 0; i < llen; i++) {
1162                 int ch = line[i];
1163                 if (ch == '/' && --nslash <= 0)
1164                         return (i == 0) ? NULL : &line[i + 1];
1165         }
1166         return NULL;
1167 }
1168
1169 /*
1170  * This is to extract the same name that appears on "diff --git"
1171  * line.  We do not find and return anything if it is a rename
1172  * patch, and it is OK because we will find the name elsewhere.
1173  * We need to reliably find name only when it is mode-change only,
1174  * creation or deletion of an empty file.  In any of these cases,
1175  * both sides are the same name under a/ and b/ respectively.
1176  */
1177 static char *git_header_name(struct apply_state *state,
1178                              const char *line,
1179                              int llen)
1180 {
1181         const char *name;
1182         const char *second = NULL;
1183         size_t len, line_len;
1184
1185         line += strlen("diff --git ");
1186         llen -= strlen("diff --git ");
1187
1188         if (*line == '"') {
1189                 const char *cp;
1190                 struct strbuf first = STRBUF_INIT;
1191                 struct strbuf sp = STRBUF_INIT;
1192
1193                 if (unquote_c_style(&first, line, &second))
1194                         goto free_and_fail1;
1195
1196                 /* strip the a/b prefix including trailing slash */
1197                 cp = skip_tree_prefix(state, first.buf, first.len);
1198                 if (!cp)
1199                         goto free_and_fail1;
1200                 strbuf_remove(&first, 0, cp - first.buf);
1201
1202                 /*
1203                  * second points at one past closing dq of name.
1204                  * find the second name.
1205                  */
1206                 while ((second < line + llen) && isspace(*second))
1207                         second++;
1208
1209                 if (line + llen <= second)
1210                         goto free_and_fail1;
1211                 if (*second == '"') {
1212                         if (unquote_c_style(&sp, second, NULL))
1213                                 goto free_and_fail1;
1214                         cp = skip_tree_prefix(state, sp.buf, sp.len);
1215                         if (!cp)
1216                                 goto free_and_fail1;
1217                         /* They must match, otherwise ignore */
1218                         if (strcmp(cp, first.buf))
1219                                 goto free_and_fail1;
1220                         strbuf_release(&sp);
1221                         return strbuf_detach(&first, NULL);
1222                 }
1223
1224                 /* unquoted second */
1225                 cp = skip_tree_prefix(state, second, line + llen - second);
1226                 if (!cp)
1227                         goto free_and_fail1;
1228                 if (line + llen - cp != first.len ||
1229                     memcmp(first.buf, cp, first.len))
1230                         goto free_and_fail1;
1231                 return strbuf_detach(&first, NULL);
1232
1233         free_and_fail1:
1234                 strbuf_release(&first);
1235                 strbuf_release(&sp);
1236                 return NULL;
1237         }
1238
1239         /* unquoted first name */
1240         name = skip_tree_prefix(state, line, llen);
1241         if (!name)
1242                 return NULL;
1243
1244         /*
1245          * since the first name is unquoted, a dq if exists must be
1246          * the beginning of the second name.
1247          */
1248         for (second = name; second < line + llen; second++) {
1249                 if (*second == '"') {
1250                         struct strbuf sp = STRBUF_INIT;
1251                         const char *np;
1252
1253                         if (unquote_c_style(&sp, second, NULL))
1254                                 goto free_and_fail2;
1255
1256                         np = skip_tree_prefix(state, sp.buf, sp.len);
1257                         if (!np)
1258                                 goto free_and_fail2;
1259
1260                         len = sp.buf + sp.len - np;
1261                         if (len < second - name &&
1262                             !strncmp(np, name, len) &&
1263                             isspace(name[len])) {
1264                                 /* Good */
1265                                 strbuf_remove(&sp, 0, np - sp.buf);
1266                                 return strbuf_detach(&sp, NULL);
1267                         }
1268
1269                 free_and_fail2:
1270                         strbuf_release(&sp);
1271                         return NULL;
1272                 }
1273         }
1274
1275         /*
1276          * Accept a name only if it shows up twice, exactly the same
1277          * form.
1278          */
1279         second = strchr(name, '\n');
1280         if (!second)
1281                 return NULL;
1282         line_len = second - name;
1283         for (len = 0 ; ; len++) {
1284                 switch (name[len]) {
1285                 default:
1286                         continue;
1287                 case '\n':
1288                         return NULL;
1289                 case '\t': case ' ':
1290                         /*
1291                          * Is this the separator between the preimage
1292                          * and the postimage pathname?  Again, we are
1293                          * only interested in the case where there is
1294                          * no rename, as this is only to set def_name
1295                          * and a rename patch has the names elsewhere
1296                          * in an unambiguous form.
1297                          */
1298                         if (!name[len + 1])
1299                                 return NULL; /* no postimage name */
1300                         second = skip_tree_prefix(state, name + len + 1,
1301                                                   line_len - (len + 1));
1302                         if (!second)
1303                                 return NULL;
1304                         /*
1305                          * Does len bytes starting at "name" and "second"
1306                          * (that are separated by one HT or SP we just
1307                          * found) exactly match?
1308                          */
1309                         if (second[len] == '\n' && !strncmp(name, second, len))
1310                                 return xmemdupz(name, len);
1311                 }
1312         }
1313 }
1314
1315 static int check_header_line(struct apply_state *state, struct patch *patch)
1316 {
1317         int extensions = (patch->is_delete == 1) + (patch->is_new == 1) +
1318                          (patch->is_rename == 1) + (patch->is_copy == 1);
1319         if (extensions > 1)
1320                 return error(_("inconsistent header lines %d and %d"),
1321                              patch->extension_linenr, state->linenr);
1322         if (extensions && !patch->extension_linenr)
1323                 patch->extension_linenr = state->linenr;
1324         return 0;
1325 }
1326
1327 /* Verify that we recognize the lines following a git header */
1328 static int parse_git_header(struct apply_state *state,
1329                             const char *line,
1330                             int len,
1331                             unsigned int size,
1332                             struct patch *patch)
1333 {
1334         unsigned long offset;
1335
1336         /* A git diff has explicit new/delete information, so we don't guess */
1337         patch->is_new = 0;
1338         patch->is_delete = 0;
1339
1340         /*
1341          * Some things may not have the old name in the
1342          * rest of the headers anywhere (pure mode changes,
1343          * or removing or adding empty files), so we get
1344          * the default name from the header.
1345          */
1346         patch->def_name = git_header_name(state, line, len);
1347         if (patch->def_name && state->root.len) {
1348                 char *s = xstrfmt("%s%s", state->root.buf, patch->def_name);
1349                 free(patch->def_name);
1350                 patch->def_name = s;
1351         }
1352
1353         line += len;
1354         size -= len;
1355         state->linenr++;
1356         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, state->linenr++) {
1357                 static const struct opentry {
1358                         const char *str;
1359                         int (*fn)(struct apply_state *, const char *, struct patch *);
1360                 } optable[] = {
1361                         { "@@ -", gitdiff_hdrend },
1362                         { "--- ", gitdiff_oldname },
1363                         { "+++ ", gitdiff_newname },
1364                         { "old mode ", gitdiff_oldmode },
1365                         { "new mode ", gitdiff_newmode },
1366                         { "deleted file mode ", gitdiff_delete },
1367                         { "new file mode ", gitdiff_newfile },
1368                         { "copy from ", gitdiff_copysrc },
1369                         { "copy to ", gitdiff_copydst },
1370                         { "rename old ", gitdiff_renamesrc },
1371                         { "rename new ", gitdiff_renamedst },
1372                         { "rename from ", gitdiff_renamesrc },
1373                         { "rename to ", gitdiff_renamedst },
1374                         { "similarity index ", gitdiff_similarity },
1375                         { "dissimilarity index ", gitdiff_dissimilarity },
1376                         { "index ", gitdiff_index },
1377                         { "", gitdiff_unrecognized },
1378                 };
1379                 int i;
1380
1381                 len = linelen(line, size);
1382                 if (!len || line[len-1] != '\n')
1383                         break;
1384                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
1385                         const struct opentry *p = optable + i;
1386                         int oplen = strlen(p->str);
1387                         int res;
1388                         if (len < oplen || memcmp(p->str, line, oplen))
1389                                 continue;
1390                         res = p->fn(state, line + oplen, patch);
1391                         if (res < 0)
1392                                 return -1;
1393                         if (check_header_line(state, patch))
1394                                 return -1;
1395                         if (res > 0)
1396                                 return offset;
1397                         break;
1398                 }
1399         }
1400
1401         return offset;
1402 }
1403
1404 static int parse_num(const char *line, unsigned long *p)
1405 {
1406         char *ptr;
1407
1408         if (!isdigit(*line))
1409                 return 0;
1410         *p = strtoul(line, &ptr, 10);
1411         return ptr - line;
1412 }
1413
1414 static int parse_range(const char *line, int len, int offset, const char *expect,
1415                        unsigned long *p1, unsigned long *p2)
1416 {
1417         int digits, ex;
1418
1419         if (offset < 0 || offset >= len)
1420                 return -1;
1421         line += offset;
1422         len -= offset;
1423
1424         digits = parse_num(line, p1);
1425         if (!digits)
1426                 return -1;
1427
1428         offset += digits;
1429         line += digits;
1430         len -= digits;
1431
1432         *p2 = 1;
1433         if (*line == ',') {
1434                 digits = parse_num(line+1, p2);
1435                 if (!digits)
1436                         return -1;
1437
1438                 offset += digits+1;
1439                 line += digits+1;
1440                 len -= digits+1;
1441         }
1442
1443         ex = strlen(expect);
1444         if (ex > len)
1445                 return -1;
1446         if (memcmp(line, expect, ex))
1447                 return -1;
1448
1449         return offset + ex;
1450 }
1451
1452 static void recount_diff(const char *line, int size, struct fragment *fragment)
1453 {
1454         int oldlines = 0, newlines = 0, ret = 0;
1455
1456         if (size < 1) {
1457                 warning("recount: ignore empty hunk");
1458                 return;
1459         }
1460
1461         for (;;) {
1462                 int len = linelen(line, size);
1463                 size -= len;
1464                 line += len;
1465
1466                 if (size < 1)
1467                         break;
1468
1469                 switch (*line) {
1470                 case ' ': case '\n':
1471                         newlines++;
1472                         /* fall through */
1473                 case '-':
1474                         oldlines++;
1475                         continue;
1476                 case '+':
1477                         newlines++;
1478                         continue;
1479                 case '\\':
1480                         continue;
1481                 case '@':
1482                         ret = size < 3 || !starts_with(line, "@@ ");
1483                         break;
1484                 case 'd':
1485                         ret = size < 5 || !starts_with(line, "diff ");
1486                         break;
1487                 default:
1488                         ret = -1;
1489                         break;
1490                 }
1491                 if (ret) {
1492                         warning(_("recount: unexpected line: %.*s"),
1493                                 (int)linelen(line, size), line);
1494                         return;
1495                 }
1496                 break;
1497         }
1498         fragment->oldlines = oldlines;
1499         fragment->newlines = newlines;
1500 }
1501
1502 /*
1503  * Parse a unified diff fragment header of the
1504  * form "@@ -a,b +c,d @@"
1505  */
1506 static int parse_fragment_header(const char *line, int len, struct fragment *fragment)
1507 {
1508         int offset;
1509
1510         if (!len || line[len-1] != '\n')
1511                 return -1;
1512
1513         /* Figure out the number of lines in a fragment */
1514         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
1515         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
1516
1517         return offset;
1518 }
1519
1520 /*
1521  * Find file diff header
1522  *
1523  * Returns:
1524  *  -1 if no header was found
1525  *  -128 in case of error
1526  *   the size of the header in bytes (called "offset") otherwise
1527  */
1528 static int find_header(struct apply_state *state,
1529                        const char *line,
1530                        unsigned long size,
1531                        int *hdrsize,
1532                        struct patch *patch)
1533 {
1534         unsigned long offset, len;
1535
1536         patch->is_toplevel_relative = 0;
1537         patch->is_rename = patch->is_copy = 0;
1538         patch->is_new = patch->is_delete = -1;
1539         patch->old_mode = patch->new_mode = 0;
1540         patch->old_name = patch->new_name = NULL;
1541         for (offset = 0; size > 0; offset += len, size -= len, line += len, state->linenr++) {
1542                 unsigned long nextlen;
1543
1544                 len = linelen(line, size);
1545                 if (!len)
1546                         break;
1547
1548                 /* Testing this early allows us to take a few shortcuts.. */
1549                 if (len < 6)
1550                         continue;
1551
1552                 /*
1553                  * Make sure we don't find any unconnected patch fragments.
1554                  * That's a sign that we didn't find a header, and that a
1555                  * patch has become corrupted/broken up.
1556                  */
1557                 if (!memcmp("@@ -", line, 4)) {
1558                         struct fragment dummy;
1559                         if (parse_fragment_header(line, len, &dummy) < 0)
1560                                 continue;
1561                         error(_("patch fragment without header at line %d: %.*s"),
1562                                      state->linenr, (int)len-1, line);
1563                         return -128;
1564                 }
1565
1566                 if (size < len + 6)
1567                         break;
1568
1569                 /*
1570                  * Git patch? It might not have a real patch, just a rename
1571                  * or mode change, so we handle that specially
1572                  */
1573                 if (!memcmp("diff --git ", line, 11)) {
1574                         int git_hdr_len = parse_git_header(state, line, len, size, patch);
1575                         if (git_hdr_len < 0)
1576                                 return -128;
1577                         if (git_hdr_len <= len)
1578                                 continue;
1579                         if (!patch->old_name && !patch->new_name) {
1580                                 if (!patch->def_name) {
1581                                         error(Q_("git diff header lacks filename information when removing "
1582                                                         "%d leading pathname component (line %d)",
1583                                                         "git diff header lacks filename information when removing "
1584                                                         "%d leading pathname components (line %d)",
1585                                                         state->p_value),
1586                                                      state->p_value, state->linenr);
1587                                         return -128;
1588                                 }
1589                                 patch->old_name = xstrdup(patch->def_name);
1590                                 patch->new_name = xstrdup(patch->def_name);
1591                         }
1592                         if ((!patch->new_name && !patch->is_delete) ||
1593                             (!patch->old_name && !patch->is_new)) {
1594                                 error(_("git diff header lacks filename information "
1595                                              "(line %d)"), state->linenr);
1596                                 return -128;
1597                         }
1598                         patch->is_toplevel_relative = 1;
1599                         *hdrsize = git_hdr_len;
1600                         return offset;
1601                 }
1602
1603                 /* --- followed by +++ ? */
1604                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1605                         continue;
1606
1607                 /*
1608                  * We only accept unified patches, so we want it to
1609                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1610                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1611                  */
1612                 nextlen = linelen(line + len, size - len);
1613                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1614                         continue;
1615
1616                 /* Ok, we'll consider it a patch */
1617                 if (parse_traditional_patch(state, line, line+len, patch))
1618                         return -128;
1619                 *hdrsize = len + nextlen;
1620                 state->linenr += 2;
1621                 return offset;
1622         }
1623         return -1;
1624 }
1625
1626 static void record_ws_error(struct apply_state *state,
1627                             unsigned result,
1628                             const char *line,
1629                             int len,
1630                             int linenr)
1631 {
1632         char *err;
1633
1634         if (!result)
1635                 return;
1636
1637         state->whitespace_error++;
1638         if (state->squelch_whitespace_errors &&
1639             state->squelch_whitespace_errors < state->whitespace_error)
1640                 return;
1641
1642         err = whitespace_error_string(result);
1643         if (state->apply_verbosity > verbosity_silent)
1644                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1645                         state->patch_input_file, linenr, err, len, line);
1646         free(err);
1647 }
1648
1649 static void check_whitespace(struct apply_state *state,
1650                              const char *line,
1651                              int len,
1652                              unsigned ws_rule)
1653 {
1654         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1655
1656         record_ws_error(state, result, line + 1, len - 2, state->linenr);
1657 }
1658
1659 /*
1660  * Check if the patch has context lines with CRLF or
1661  * the patch wants to remove lines with CRLF.
1662  */
1663 static void check_old_for_crlf(struct patch *patch, const char *line, int len)
1664 {
1665         if (len >= 2 && line[len-1] == '\n' && line[len-2] == '\r') {
1666                 patch->ws_rule |= WS_CR_AT_EOL;
1667                 patch->crlf_in_old = 1;
1668         }
1669 }
1670
1671
1672 /*
1673  * Parse a unified diff. Note that this really needs to parse each
1674  * fragment separately, since the only way to know the difference
1675  * between a "---" that is part of a patch, and a "---" that starts
1676  * the next patch is to look at the line counts..
1677  */
1678 static int parse_fragment(struct apply_state *state,
1679                           const char *line,
1680                           unsigned long size,
1681                           struct patch *patch,
1682                           struct fragment *fragment)
1683 {
1684         int added, deleted;
1685         int len = linelen(line, size), offset;
1686         unsigned long oldlines, newlines;
1687         unsigned long leading, trailing;
1688
1689         offset = parse_fragment_header(line, len, fragment);
1690         if (offset < 0)
1691                 return -1;
1692         if (offset > 0 && patch->recount)
1693                 recount_diff(line + offset, size - offset, fragment);
1694         oldlines = fragment->oldlines;
1695         newlines = fragment->newlines;
1696         leading = 0;
1697         trailing = 0;
1698
1699         /* Parse the thing.. */
1700         line += len;
1701         size -= len;
1702         state->linenr++;
1703         added = deleted = 0;
1704         for (offset = len;
1705              0 < size;
1706              offset += len, size -= len, line += len, state->linenr++) {
1707                 if (!oldlines && !newlines)
1708                         break;
1709                 len = linelen(line, size);
1710                 if (!len || line[len-1] != '\n')
1711                         return -1;
1712                 switch (*line) {
1713                 default:
1714                         return -1;
1715                 case '\n': /* newer GNU diff, an empty context line */
1716                 case ' ':
1717                         oldlines--;
1718                         newlines--;
1719                         if (!deleted && !added)
1720                                 leading++;
1721                         trailing++;
1722                         check_old_for_crlf(patch, line, len);
1723                         if (!state->apply_in_reverse &&
1724                             state->ws_error_action == correct_ws_error)
1725                                 check_whitespace(state, line, len, patch->ws_rule);
1726                         break;
1727                 case '-':
1728                         if (!state->apply_in_reverse)
1729                                 check_old_for_crlf(patch, line, len);
1730                         if (state->apply_in_reverse &&
1731                             state->ws_error_action != nowarn_ws_error)
1732                                 check_whitespace(state, line, len, patch->ws_rule);
1733                         deleted++;
1734                         oldlines--;
1735                         trailing = 0;
1736                         break;
1737                 case '+':
1738                         if (state->apply_in_reverse)
1739                                 check_old_for_crlf(patch, line, len);
1740                         if (!state->apply_in_reverse &&
1741                             state->ws_error_action != nowarn_ws_error)
1742                                 check_whitespace(state, line, len, patch->ws_rule);
1743                         added++;
1744                         newlines--;
1745                         trailing = 0;
1746                         break;
1747
1748                 /*
1749                  * We allow "\ No newline at end of file". Depending
1750                  * on locale settings when the patch was produced we
1751                  * don't know what this line looks like. The only
1752                  * thing we do know is that it begins with "\ ".
1753                  * Checking for 12 is just for sanity check -- any
1754                  * l10n of "\ No newline..." is at least that long.
1755                  */
1756                 case '\\':
1757                         if (len < 12 || memcmp(line, "\\ ", 2))
1758                                 return -1;
1759                         break;
1760                 }
1761         }
1762         if (oldlines || newlines)
1763                 return -1;
1764         if (!deleted && !added)
1765                 return -1;
1766
1767         fragment->leading = leading;
1768         fragment->trailing = trailing;
1769
1770         /*
1771          * If a fragment ends with an incomplete line, we failed to include
1772          * it in the above loop because we hit oldlines == newlines == 0
1773          * before seeing it.
1774          */
1775         if (12 < size && !memcmp(line, "\\ ", 2))
1776                 offset += linelen(line, size);
1777
1778         patch->lines_added += added;
1779         patch->lines_deleted += deleted;
1780
1781         if (0 < patch->is_new && oldlines)
1782                 return error(_("new file depends on old contents"));
1783         if (0 < patch->is_delete && newlines)
1784                 return error(_("deleted file still has contents"));
1785         return offset;
1786 }
1787
1788 /*
1789  * We have seen "diff --git a/... b/..." header (or a traditional patch
1790  * header).  Read hunks that belong to this patch into fragments and hang
1791  * them to the given patch structure.
1792  *
1793  * The (fragment->patch, fragment->size) pair points into the memory given
1794  * by the caller, not a copy, when we return.
1795  *
1796  * Returns:
1797  *   -1 in case of error,
1798  *   the number of bytes in the patch otherwise.
1799  */
1800 static int parse_single_patch(struct apply_state *state,
1801                               const char *line,
1802                               unsigned long size,
1803                               struct patch *patch)
1804 {
1805         unsigned long offset = 0;
1806         unsigned long oldlines = 0, newlines = 0, context = 0;
1807         struct fragment **fragp = &patch->fragments;
1808
1809         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1810                 struct fragment *fragment;
1811                 int len;
1812
1813                 fragment = xcalloc(1, sizeof(*fragment));
1814                 fragment->linenr = state->linenr;
1815                 len = parse_fragment(state, line, size, patch, fragment);
1816                 if (len <= 0) {
1817                         free(fragment);
1818                         return error(_("corrupt patch at line %d"), state->linenr);
1819                 }
1820                 fragment->patch = line;
1821                 fragment->size = len;
1822                 oldlines += fragment->oldlines;
1823                 newlines += fragment->newlines;
1824                 context += fragment->leading + fragment->trailing;
1825
1826                 *fragp = fragment;
1827                 fragp = &fragment->next;
1828
1829                 offset += len;
1830                 line += len;
1831                 size -= len;
1832         }
1833
1834         /*
1835          * If something was removed (i.e. we have old-lines) it cannot
1836          * be creation, and if something was added it cannot be
1837          * deletion.  However, the reverse is not true; --unified=0
1838          * patches that only add are not necessarily creation even
1839          * though they do not have any old lines, and ones that only
1840          * delete are not necessarily deletion.
1841          *
1842          * Unfortunately, a real creation/deletion patch do _not_ have
1843          * any context line by definition, so we cannot safely tell it
1844          * apart with --unified=0 insanity.  At least if the patch has
1845          * more than one hunk it is not creation or deletion.
1846          */
1847         if (patch->is_new < 0 &&
1848             (oldlines || (patch->fragments && patch->fragments->next)))
1849                 patch->is_new = 0;
1850         if (patch->is_delete < 0 &&
1851             (newlines || (patch->fragments && patch->fragments->next)))
1852                 patch->is_delete = 0;
1853
1854         if (0 < patch->is_new && oldlines)
1855                 return error(_("new file %s depends on old contents"), patch->new_name);
1856         if (0 < patch->is_delete && newlines)
1857                 return error(_("deleted file %s still has contents"), patch->old_name);
1858         if (!patch->is_delete && !newlines && context && state->apply_verbosity > verbosity_silent)
1859                 fprintf_ln(stderr,
1860                            _("** warning: "
1861                              "file %s becomes empty but is not deleted"),
1862                            patch->new_name);
1863
1864         return offset;
1865 }
1866
1867 static inline int metadata_changes(struct patch *patch)
1868 {
1869         return  patch->is_rename > 0 ||
1870                 patch->is_copy > 0 ||
1871                 patch->is_new > 0 ||
1872                 patch->is_delete ||
1873                 (patch->old_mode && patch->new_mode &&
1874                  patch->old_mode != patch->new_mode);
1875 }
1876
1877 static char *inflate_it(const void *data, unsigned long size,
1878                         unsigned long inflated_size)
1879 {
1880         git_zstream stream;
1881         void *out;
1882         int st;
1883
1884         memset(&stream, 0, sizeof(stream));
1885
1886         stream.next_in = (unsigned char *)data;
1887         stream.avail_in = size;
1888         stream.next_out = out = xmalloc(inflated_size);
1889         stream.avail_out = inflated_size;
1890         git_inflate_init(&stream);
1891         st = git_inflate(&stream, Z_FINISH);
1892         git_inflate_end(&stream);
1893         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1894                 free(out);
1895                 return NULL;
1896         }
1897         return out;
1898 }
1899
1900 /*
1901  * Read a binary hunk and return a new fragment; fragment->patch
1902  * points at an allocated memory that the caller must free, so
1903  * it is marked as "->free_patch = 1".
1904  */
1905 static struct fragment *parse_binary_hunk(struct apply_state *state,
1906                                           char **buf_p,
1907                                           unsigned long *sz_p,
1908                                           int *status_p,
1909                                           int *used_p)
1910 {
1911         /*
1912          * Expect a line that begins with binary patch method ("literal"
1913          * or "delta"), followed by the length of data before deflating.
1914          * a sequence of 'length-byte' followed by base-85 encoded data
1915          * should follow, terminated by a newline.
1916          *
1917          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1918          * and we would limit the patch line to 66 characters,
1919          * so one line can fit up to 13 groups that would decode
1920          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1921          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1922          */
1923         int llen, used;
1924         unsigned long size = *sz_p;
1925         char *buffer = *buf_p;
1926         int patch_method;
1927         unsigned long origlen;
1928         char *data = NULL;
1929         int hunk_size = 0;
1930         struct fragment *frag;
1931
1932         llen = linelen(buffer, size);
1933         used = llen;
1934
1935         *status_p = 0;
1936
1937         if (starts_with(buffer, "delta ")) {
1938                 patch_method = BINARY_DELTA_DEFLATED;
1939                 origlen = strtoul(buffer + 6, NULL, 10);
1940         }
1941         else if (starts_with(buffer, "literal ")) {
1942                 patch_method = BINARY_LITERAL_DEFLATED;
1943                 origlen = strtoul(buffer + 8, NULL, 10);
1944         }
1945         else
1946                 return NULL;
1947
1948         state->linenr++;
1949         buffer += llen;
1950         while (1) {
1951                 int byte_length, max_byte_length, newsize;
1952                 llen = linelen(buffer, size);
1953                 used += llen;
1954                 state->linenr++;
1955                 if (llen == 1) {
1956                         /* consume the blank line */
1957                         buffer++;
1958                         size--;
1959                         break;
1960                 }
1961                 /*
1962                  * Minimum line is "A00000\n" which is 7-byte long,
1963                  * and the line length must be multiple of 5 plus 2.
1964                  */
1965                 if ((llen < 7) || (llen-2) % 5)
1966                         goto corrupt;
1967                 max_byte_length = (llen - 2) / 5 * 4;
1968                 byte_length = *buffer;
1969                 if ('A' <= byte_length && byte_length <= 'Z')
1970                         byte_length = byte_length - 'A' + 1;
1971                 else if ('a' <= byte_length && byte_length <= 'z')
1972                         byte_length = byte_length - 'a' + 27;
1973                 else
1974                         goto corrupt;
1975                 /* if the input length was not multiple of 4, we would
1976                  * have filler at the end but the filler should never
1977                  * exceed 3 bytes
1978                  */
1979                 if (max_byte_length < byte_length ||
1980                     byte_length <= max_byte_length - 4)
1981                         goto corrupt;
1982                 newsize = hunk_size + byte_length;
1983                 data = xrealloc(data, newsize);
1984                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1985                         goto corrupt;
1986                 hunk_size = newsize;
1987                 buffer += llen;
1988                 size -= llen;
1989         }
1990
1991         frag = xcalloc(1, sizeof(*frag));
1992         frag->patch = inflate_it(data, hunk_size, origlen);
1993         frag->free_patch = 1;
1994         if (!frag->patch)
1995                 goto corrupt;
1996         free(data);
1997         frag->size = origlen;
1998         *buf_p = buffer;
1999         *sz_p = size;
2000         *used_p = used;
2001         frag->binary_patch_method = patch_method;
2002         return frag;
2003
2004  corrupt:
2005         free(data);
2006         *status_p = -1;
2007         error(_("corrupt binary patch at line %d: %.*s"),
2008               state->linenr-1, llen-1, buffer);
2009         return NULL;
2010 }
2011
2012 /*
2013  * Returns:
2014  *   -1 in case of error,
2015  *   the length of the parsed binary patch otherwise
2016  */
2017 static int parse_binary(struct apply_state *state,
2018                         char *buffer,
2019                         unsigned long size,
2020                         struct patch *patch)
2021 {
2022         /*
2023          * We have read "GIT binary patch\n"; what follows is a line
2024          * that says the patch method (currently, either "literal" or
2025          * "delta") and the length of data before deflating; a
2026          * sequence of 'length-byte' followed by base-85 encoded data
2027          * follows.
2028          *
2029          * When a binary patch is reversible, there is another binary
2030          * hunk in the same format, starting with patch method (either
2031          * "literal" or "delta") with the length of data, and a sequence
2032          * of length-byte + base-85 encoded data, terminated with another
2033          * empty line.  This data, when applied to the postimage, produces
2034          * the preimage.
2035          */
2036         struct fragment *forward;
2037         struct fragment *reverse;
2038         int status;
2039         int used, used_1;
2040
2041         forward = parse_binary_hunk(state, &buffer, &size, &status, &used);
2042         if (!forward && !status)
2043                 /* there has to be one hunk (forward hunk) */
2044                 return error(_("unrecognized binary patch at line %d"), state->linenr-1);
2045         if (status)
2046                 /* otherwise we already gave an error message */
2047                 return status;
2048
2049         reverse = parse_binary_hunk(state, &buffer, &size, &status, &used_1);
2050         if (reverse)
2051                 used += used_1;
2052         else if (status) {
2053                 /*
2054                  * Not having reverse hunk is not an error, but having
2055                  * a corrupt reverse hunk is.
2056                  */
2057                 free((void*) forward->patch);
2058                 free(forward);
2059                 return status;
2060         }
2061         forward->next = reverse;
2062         patch->fragments = forward;
2063         patch->is_binary = 1;
2064         return used;
2065 }
2066
2067 static void prefix_one(struct apply_state *state, char **name)
2068 {
2069         char *old_name = *name;
2070         if (!old_name)
2071                 return;
2072         *name = prefix_filename(state->prefix, *name);
2073         free(old_name);
2074 }
2075
2076 static void prefix_patch(struct apply_state *state, struct patch *p)
2077 {
2078         if (!state->prefix || p->is_toplevel_relative)
2079                 return;
2080         prefix_one(state, &p->new_name);
2081         prefix_one(state, &p->old_name);
2082 }
2083
2084 /*
2085  * include/exclude
2086  */
2087
2088 static void add_name_limit(struct apply_state *state,
2089                            const char *name,
2090                            int exclude)
2091 {
2092         struct string_list_item *it;
2093
2094         it = string_list_append(&state->limit_by_name, name);
2095         it->util = exclude ? NULL : (void *) 1;
2096 }
2097
2098 static int use_patch(struct apply_state *state, struct patch *p)
2099 {
2100         const char *pathname = p->new_name ? p->new_name : p->old_name;
2101         int i;
2102
2103         /* Paths outside are not touched regardless of "--include" */
2104         if (state->prefix && *state->prefix) {
2105                 const char *rest;
2106                 if (!skip_prefix(pathname, state->prefix, &rest) || !*rest)
2107                         return 0;
2108         }
2109
2110         /* See if it matches any of exclude/include rule */
2111         for (i = 0; i < state->limit_by_name.nr; i++) {
2112                 struct string_list_item *it = &state->limit_by_name.items[i];
2113                 if (!wildmatch(it->string, pathname, 0))
2114                         return (it->util != NULL);
2115         }
2116
2117         /*
2118          * If we had any include, a path that does not match any rule is
2119          * not used.  Otherwise, we saw bunch of exclude rules (or none)
2120          * and such a path is used.
2121          */
2122         return !state->has_include;
2123 }
2124
2125 /*
2126  * Read the patch text in "buffer" that extends for "size" bytes; stop
2127  * reading after seeing a single patch (i.e. changes to a single file).
2128  * Create fragments (i.e. patch hunks) and hang them to the given patch.
2129  *
2130  * Returns:
2131  *   -1 if no header was found or parse_binary() failed,
2132  *   -128 on another error,
2133  *   the number of bytes consumed otherwise,
2134  *     so that the caller can call us again for the next patch.
2135  */
2136 static int parse_chunk(struct apply_state *state, char *buffer, unsigned long size, struct patch *patch)
2137 {
2138         int hdrsize, patchsize;
2139         int offset = find_header(state, buffer, size, &hdrsize, patch);
2140
2141         if (offset < 0)
2142                 return offset;
2143
2144         prefix_patch(state, patch);
2145
2146         if (!use_patch(state, patch))
2147                 patch->ws_rule = 0;
2148         else
2149                 patch->ws_rule = whitespace_rule(patch->new_name
2150                                                  ? patch->new_name
2151                                                  : patch->old_name);
2152
2153         patchsize = parse_single_patch(state,
2154                                        buffer + offset + hdrsize,
2155                                        size - offset - hdrsize,
2156                                        patch);
2157
2158         if (patchsize < 0)
2159                 return -128;
2160
2161         if (!patchsize) {
2162                 static const char git_binary[] = "GIT binary patch\n";
2163                 int hd = hdrsize + offset;
2164                 unsigned long llen = linelen(buffer + hd, size - hd);
2165
2166                 if (llen == sizeof(git_binary) - 1 &&
2167                     !memcmp(git_binary, buffer + hd, llen)) {
2168                         int used;
2169                         state->linenr++;
2170                         used = parse_binary(state, buffer + hd + llen,
2171                                             size - hd - llen, patch);
2172                         if (used < 0)
2173                                 return -1;
2174                         if (used)
2175                                 patchsize = used + llen;
2176                         else
2177                                 patchsize = 0;
2178                 }
2179                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
2180                         static const char *binhdr[] = {
2181                                 "Binary files ",
2182                                 "Files ",
2183                                 NULL,
2184                         };
2185                         int i;
2186                         for (i = 0; binhdr[i]; i++) {
2187                                 int len = strlen(binhdr[i]);
2188                                 if (len < size - hd &&
2189                                     !memcmp(binhdr[i], buffer + hd, len)) {
2190                                         state->linenr++;
2191                                         patch->is_binary = 1;
2192                                         patchsize = llen;
2193                                         break;
2194                                 }
2195                         }
2196                 }
2197
2198                 /* Empty patch cannot be applied if it is a text patch
2199                  * without metadata change.  A binary patch appears
2200                  * empty to us here.
2201                  */
2202                 if ((state->apply || state->check) &&
2203                     (!patch->is_binary && !metadata_changes(patch))) {
2204                         error(_("patch with only garbage at line %d"), state->linenr);
2205                         return -128;
2206                 }
2207         }
2208
2209         return offset + hdrsize + patchsize;
2210 }
2211
2212 static void reverse_patches(struct patch *p)
2213 {
2214         for (; p; p = p->next) {
2215                 struct fragment *frag = p->fragments;
2216
2217                 SWAP(p->new_name, p->old_name);
2218                 SWAP(p->new_mode, p->old_mode);
2219                 SWAP(p->is_new, p->is_delete);
2220                 SWAP(p->lines_added, p->lines_deleted);
2221                 SWAP(p->old_sha1_prefix, p->new_sha1_prefix);
2222
2223                 for (; frag; frag = frag->next) {
2224                         SWAP(frag->newpos, frag->oldpos);
2225                         SWAP(frag->newlines, frag->oldlines);
2226                 }
2227         }
2228 }
2229
2230 static const char pluses[] =
2231 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
2232 static const char minuses[]=
2233 "----------------------------------------------------------------------";
2234
2235 static void show_stats(struct apply_state *state, struct patch *patch)
2236 {
2237         struct strbuf qname = STRBUF_INIT;
2238         char *cp = patch->new_name ? patch->new_name : patch->old_name;
2239         int max, add, del;
2240
2241         quote_c_style(cp, &qname, NULL, 0);
2242
2243         /*
2244          * "scale" the filename
2245          */
2246         max = state->max_len;
2247         if (max > 50)
2248                 max = 50;
2249
2250         if (qname.len > max) {
2251                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
2252                 if (!cp)
2253                         cp = qname.buf + qname.len + 3 - max;
2254                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
2255         }
2256
2257         if (patch->is_binary) {
2258                 printf(" %-*s |  Bin\n", max, qname.buf);
2259                 strbuf_release(&qname);
2260                 return;
2261         }
2262
2263         printf(" %-*s |", max, qname.buf);
2264         strbuf_release(&qname);
2265
2266         /*
2267          * scale the add/delete
2268          */
2269         max = max + state->max_change > 70 ? 70 - max : state->max_change;
2270         add = patch->lines_added;
2271         del = patch->lines_deleted;
2272
2273         if (state->max_change > 0) {
2274                 int total = ((add + del) * max + state->max_change / 2) / state->max_change;
2275                 add = (add * max + state->max_change / 2) / state->max_change;
2276                 del = total - add;
2277         }
2278         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
2279                 add, pluses, del, minuses);
2280 }
2281
2282 static int read_old_data(struct stat *st, struct patch *patch,
2283                          const char *path, struct strbuf *buf)
2284 {
2285         enum safe_crlf safe_crlf = patch->crlf_in_old ?
2286                 SAFE_CRLF_KEEP_CRLF : SAFE_CRLF_RENORMALIZE;
2287         switch (st->st_mode & S_IFMT) {
2288         case S_IFLNK:
2289                 if (strbuf_readlink(buf, path, st->st_size) < 0)
2290                         return error(_("unable to read symlink %s"), path);
2291                 return 0;
2292         case S_IFREG:
2293                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
2294                         return error(_("unable to open or read %s"), path);
2295                 /*
2296                  * "git apply" without "--index/--cached" should never look
2297                  * at the index; the target file may not have been added to
2298                  * the index yet, and we may not even be in any Git repository.
2299                  * Pass NULL to convert_to_git() to stress this; the function
2300                  * should never look at the index when explicit crlf option
2301                  * is given.
2302                  */
2303                 convert_to_git(NULL, path, buf->buf, buf->len, buf, safe_crlf);
2304                 return 0;
2305         default:
2306                 return -1;
2307         }
2308 }
2309
2310 /*
2311  * Update the preimage, and the common lines in postimage,
2312  * from buffer buf of length len. If postlen is 0 the postimage
2313  * is updated in place, otherwise it's updated on a new buffer
2314  * of length postlen
2315  */
2316
2317 static void update_pre_post_images(struct image *preimage,
2318                                    struct image *postimage,
2319                                    char *buf,
2320                                    size_t len, size_t postlen)
2321 {
2322         int i, ctx, reduced;
2323         char *new, *old, *fixed;
2324         struct image fixed_preimage;
2325
2326         /*
2327          * Update the preimage with whitespace fixes.  Note that we
2328          * are not losing preimage->buf -- apply_one_fragment() will
2329          * free "oldlines".
2330          */
2331         prepare_image(&fixed_preimage, buf, len, 1);
2332         assert(postlen
2333                ? fixed_preimage.nr == preimage->nr
2334                : fixed_preimage.nr <= preimage->nr);
2335         for (i = 0; i < fixed_preimage.nr; i++)
2336                 fixed_preimage.line[i].flag = preimage->line[i].flag;
2337         free(preimage->line_allocated);
2338         *preimage = fixed_preimage;
2339
2340         /*
2341          * Adjust the common context lines in postimage. This can be
2342          * done in-place when we are shrinking it with whitespace
2343          * fixing, but needs a new buffer when ignoring whitespace or
2344          * expanding leading tabs to spaces.
2345          *
2346          * We trust the caller to tell us if the update can be done
2347          * in place (postlen==0) or not.
2348          */
2349         old = postimage->buf;
2350         if (postlen)
2351                 new = postimage->buf = xmalloc(postlen);
2352         else
2353                 new = old;
2354         fixed = preimage->buf;
2355
2356         for (i = reduced = ctx = 0; i < postimage->nr; i++) {
2357                 size_t l_len = postimage->line[i].len;
2358                 if (!(postimage->line[i].flag & LINE_COMMON)) {
2359                         /* an added line -- no counterparts in preimage */
2360                         memmove(new, old, l_len);
2361                         old += l_len;
2362                         new += l_len;
2363                         continue;
2364                 }
2365
2366                 /* a common context -- skip it in the original postimage */
2367                 old += l_len;
2368
2369                 /* and find the corresponding one in the fixed preimage */
2370                 while (ctx < preimage->nr &&
2371                        !(preimage->line[ctx].flag & LINE_COMMON)) {
2372                         fixed += preimage->line[ctx].len;
2373                         ctx++;
2374                 }
2375
2376                 /*
2377                  * preimage is expected to run out, if the caller
2378                  * fixed addition of trailing blank lines.
2379                  */
2380                 if (preimage->nr <= ctx) {
2381                         reduced++;
2382                         continue;
2383                 }
2384
2385                 /* and copy it in, while fixing the line length */
2386                 l_len = preimage->line[ctx].len;
2387                 memcpy(new, fixed, l_len);
2388                 new += l_len;
2389                 fixed += l_len;
2390                 postimage->line[i].len = l_len;
2391                 ctx++;
2392         }
2393
2394         if (postlen
2395             ? postlen < new - postimage->buf
2396             : postimage->len < new - postimage->buf)
2397                 die("BUG: caller miscounted postlen: asked %d, orig = %d, used = %d",
2398                     (int)postlen, (int) postimage->len, (int)(new - postimage->buf));
2399
2400         /* Fix the length of the whole thing */
2401         postimage->len = new - postimage->buf;
2402         postimage->nr -= reduced;
2403 }
2404
2405 static int line_by_line_fuzzy_match(struct image *img,
2406                                     struct image *preimage,
2407                                     struct image *postimage,
2408                                     unsigned long try,
2409                                     int try_lno,
2410                                     int preimage_limit)
2411 {
2412         int i;
2413         size_t imgoff = 0;
2414         size_t preoff = 0;
2415         size_t postlen = postimage->len;
2416         size_t extra_chars;
2417         char *buf;
2418         char *preimage_eof;
2419         char *preimage_end;
2420         struct strbuf fixed;
2421         char *fixed_buf;
2422         size_t fixed_len;
2423
2424         for (i = 0; i < preimage_limit; i++) {
2425                 size_t prelen = preimage->line[i].len;
2426                 size_t imglen = img->line[try_lno+i].len;
2427
2428                 if (!fuzzy_matchlines(img->buf + try + imgoff, imglen,
2429                                       preimage->buf + preoff, prelen))
2430                         return 0;
2431                 if (preimage->line[i].flag & LINE_COMMON)
2432                         postlen += imglen - prelen;
2433                 imgoff += imglen;
2434                 preoff += prelen;
2435         }
2436
2437         /*
2438          * Ok, the preimage matches with whitespace fuzz.
2439          *
2440          * imgoff now holds the true length of the target that
2441          * matches the preimage before the end of the file.
2442          *
2443          * Count the number of characters in the preimage that fall
2444          * beyond the end of the file and make sure that all of them
2445          * are whitespace characters. (This can only happen if
2446          * we are removing blank lines at the end of the file.)
2447          */
2448         buf = preimage_eof = preimage->buf + preoff;
2449         for ( ; i < preimage->nr; i++)
2450                 preoff += preimage->line[i].len;
2451         preimage_end = preimage->buf + preoff;
2452         for ( ; buf < preimage_end; buf++)
2453                 if (!isspace(*buf))
2454                         return 0;
2455
2456         /*
2457          * Update the preimage and the common postimage context
2458          * lines to use the same whitespace as the target.
2459          * If whitespace is missing in the target (i.e.
2460          * if the preimage extends beyond the end of the file),
2461          * use the whitespace from the preimage.
2462          */
2463         extra_chars = preimage_end - preimage_eof;
2464         strbuf_init(&fixed, imgoff + extra_chars);
2465         strbuf_add(&fixed, img->buf + try, imgoff);
2466         strbuf_add(&fixed, preimage_eof, extra_chars);
2467         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2468         update_pre_post_images(preimage, postimage,
2469                                fixed_buf, fixed_len, postlen);
2470         return 1;
2471 }
2472
2473 static int match_fragment(struct apply_state *state,
2474                           struct image *img,
2475                           struct image *preimage,
2476                           struct image *postimage,
2477                           unsigned long try,
2478                           int try_lno,
2479                           unsigned ws_rule,
2480                           int match_beginning, int match_end)
2481 {
2482         int i;
2483         char *fixed_buf, *buf, *orig, *target;
2484         struct strbuf fixed;
2485         size_t fixed_len, postlen;
2486         int preimage_limit;
2487
2488         if (preimage->nr + try_lno <= img->nr) {
2489                 /*
2490                  * The hunk falls within the boundaries of img.
2491                  */
2492                 preimage_limit = preimage->nr;
2493                 if (match_end && (preimage->nr + try_lno != img->nr))
2494                         return 0;
2495         } else if (state->ws_error_action == correct_ws_error &&
2496                    (ws_rule & WS_BLANK_AT_EOF)) {
2497                 /*
2498                  * This hunk extends beyond the end of img, and we are
2499                  * removing blank lines at the end of the file.  This
2500                  * many lines from the beginning of the preimage must
2501                  * match with img, and the remainder of the preimage
2502                  * must be blank.
2503                  */
2504                 preimage_limit = img->nr - try_lno;
2505         } else {
2506                 /*
2507                  * The hunk extends beyond the end of the img and
2508                  * we are not removing blanks at the end, so we
2509                  * should reject the hunk at this position.
2510                  */
2511                 return 0;
2512         }
2513
2514         if (match_beginning && try_lno)
2515                 return 0;
2516
2517         /* Quick hash check */
2518         for (i = 0; i < preimage_limit; i++)
2519                 if ((img->line[try_lno + i].flag & LINE_PATCHED) ||
2520                     (preimage->line[i].hash != img->line[try_lno + i].hash))
2521                         return 0;
2522
2523         if (preimage_limit == preimage->nr) {
2524                 /*
2525                  * Do we have an exact match?  If we were told to match
2526                  * at the end, size must be exactly at try+fragsize,
2527                  * otherwise try+fragsize must be still within the preimage,
2528                  * and either case, the old piece should match the preimage
2529                  * exactly.
2530                  */
2531                 if ((match_end
2532                      ? (try + preimage->len == img->len)
2533                      : (try + preimage->len <= img->len)) &&
2534                     !memcmp(img->buf + try, preimage->buf, preimage->len))
2535                         return 1;
2536         } else {
2537                 /*
2538                  * The preimage extends beyond the end of img, so
2539                  * there cannot be an exact match.
2540                  *
2541                  * There must be one non-blank context line that match
2542                  * a line before the end of img.
2543                  */
2544                 char *buf_end;
2545
2546                 buf = preimage->buf;
2547                 buf_end = buf;
2548                 for (i = 0; i < preimage_limit; i++)
2549                         buf_end += preimage->line[i].len;
2550
2551                 for ( ; buf < buf_end; buf++)
2552                         if (!isspace(*buf))
2553                                 break;
2554                 if (buf == buf_end)
2555                         return 0;
2556         }
2557
2558         /*
2559          * No exact match. If we are ignoring whitespace, run a line-by-line
2560          * fuzzy matching. We collect all the line length information because
2561          * we need it to adjust whitespace if we match.
2562          */
2563         if (state->ws_ignore_action == ignore_ws_change)
2564                 return line_by_line_fuzzy_match(img, preimage, postimage,
2565                                                 try, try_lno, preimage_limit);
2566
2567         if (state->ws_error_action != correct_ws_error)
2568                 return 0;
2569
2570         /*
2571          * The hunk does not apply byte-by-byte, but the hash says
2572          * it might with whitespace fuzz. We weren't asked to
2573          * ignore whitespace, we were asked to correct whitespace
2574          * errors, so let's try matching after whitespace correction.
2575          *
2576          * While checking the preimage against the target, whitespace
2577          * errors in both fixed, we count how large the corresponding
2578          * postimage needs to be.  The postimage prepared by
2579          * apply_one_fragment() has whitespace errors fixed on added
2580          * lines already, but the common lines were propagated as-is,
2581          * which may become longer when their whitespace errors are
2582          * fixed.
2583          */
2584
2585         /* First count added lines in postimage */
2586         postlen = 0;
2587         for (i = 0; i < postimage->nr; i++) {
2588                 if (!(postimage->line[i].flag & LINE_COMMON))
2589                         postlen += postimage->line[i].len;
2590         }
2591
2592         /*
2593          * The preimage may extend beyond the end of the file,
2594          * but in this loop we will only handle the part of the
2595          * preimage that falls within the file.
2596          */
2597         strbuf_init(&fixed, preimage->len + 1);
2598         orig = preimage->buf;
2599         target = img->buf + try;
2600         for (i = 0; i < preimage_limit; i++) {
2601                 size_t oldlen = preimage->line[i].len;
2602                 size_t tgtlen = img->line[try_lno + i].len;
2603                 size_t fixstart = fixed.len;
2604                 struct strbuf tgtfix;
2605                 int match;
2606
2607                 /* Try fixing the line in the preimage */
2608                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2609
2610                 /* Try fixing the line in the target */
2611                 strbuf_init(&tgtfix, tgtlen);
2612                 ws_fix_copy(&tgtfix, target, tgtlen, ws_rule, NULL);
2613
2614                 /*
2615                  * If they match, either the preimage was based on
2616                  * a version before our tree fixed whitespace breakage,
2617                  * or we are lacking a whitespace-fix patch the tree
2618                  * the preimage was based on already had (i.e. target
2619                  * has whitespace breakage, the preimage doesn't).
2620                  * In either case, we are fixing the whitespace breakages
2621                  * so we might as well take the fix together with their
2622                  * real change.
2623                  */
2624                 match = (tgtfix.len == fixed.len - fixstart &&
2625                          !memcmp(tgtfix.buf, fixed.buf + fixstart,
2626                                              fixed.len - fixstart));
2627
2628                 /* Add the length if this is common with the postimage */
2629                 if (preimage->line[i].flag & LINE_COMMON)
2630                         postlen += tgtfix.len;
2631
2632                 strbuf_release(&tgtfix);
2633                 if (!match)
2634                         goto unmatch_exit;
2635
2636                 orig += oldlen;
2637                 target += tgtlen;
2638         }
2639
2640
2641         /*
2642          * Now handle the lines in the preimage that falls beyond the
2643          * end of the file (if any). They will only match if they are
2644          * empty or only contain whitespace (if WS_BLANK_AT_EOL is
2645          * false).
2646          */
2647         for ( ; i < preimage->nr; i++) {
2648                 size_t fixstart = fixed.len; /* start of the fixed preimage */
2649                 size_t oldlen = preimage->line[i].len;
2650                 int j;
2651
2652                 /* Try fixing the line in the preimage */
2653                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2654
2655                 for (j = fixstart; j < fixed.len; j++)
2656                         if (!isspace(fixed.buf[j]))
2657                                 goto unmatch_exit;
2658
2659                 orig += oldlen;
2660         }
2661
2662         /*
2663          * Yes, the preimage is based on an older version that still
2664          * has whitespace breakages unfixed, and fixing them makes the
2665          * hunk match.  Update the context lines in the postimage.
2666          */
2667         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2668         if (postlen < postimage->len)
2669                 postlen = 0;
2670         update_pre_post_images(preimage, postimage,
2671                                fixed_buf, fixed_len, postlen);
2672         return 1;
2673
2674  unmatch_exit:
2675         strbuf_release(&fixed);
2676         return 0;
2677 }
2678
2679 static int find_pos(struct apply_state *state,
2680                     struct image *img,
2681                     struct image *preimage,
2682                     struct image *postimage,
2683                     int line,
2684                     unsigned ws_rule,
2685                     int match_beginning, int match_end)
2686 {
2687         int i;
2688         unsigned long backwards, forwards, try;
2689         int backwards_lno, forwards_lno, try_lno;
2690
2691         /*
2692          * If match_beginning or match_end is specified, there is no
2693          * point starting from a wrong line that will never match and
2694          * wander around and wait for a match at the specified end.
2695          */
2696         if (match_beginning)
2697                 line = 0;
2698         else if (match_end)
2699                 line = img->nr - preimage->nr;
2700
2701         /*
2702          * Because the comparison is unsigned, the following test
2703          * will also take care of a negative line number that can
2704          * result when match_end and preimage is larger than the target.
2705          */
2706         if ((size_t) line > img->nr)
2707                 line = img->nr;
2708
2709         try = 0;
2710         for (i = 0; i < line; i++)
2711                 try += img->line[i].len;
2712
2713         /*
2714          * There's probably some smart way to do this, but I'll leave
2715          * that to the smart and beautiful people. I'm simple and stupid.
2716          */
2717         backwards = try;
2718         backwards_lno = line;
2719         forwards = try;
2720         forwards_lno = line;
2721         try_lno = line;
2722
2723         for (i = 0; ; i++) {
2724                 if (match_fragment(state, img, preimage, postimage,
2725                                    try, try_lno, ws_rule,
2726                                    match_beginning, match_end))
2727                         return try_lno;
2728
2729         again:
2730                 if (backwards_lno == 0 && forwards_lno == img->nr)
2731                         break;
2732
2733                 if (i & 1) {
2734                         if (backwards_lno == 0) {
2735                                 i++;
2736                                 goto again;
2737                         }
2738                         backwards_lno--;
2739                         backwards -= img->line[backwards_lno].len;
2740                         try = backwards;
2741                         try_lno = backwards_lno;
2742                 } else {
2743                         if (forwards_lno == img->nr) {
2744                                 i++;
2745                                 goto again;
2746                         }
2747                         forwards += img->line[forwards_lno].len;
2748                         forwards_lno++;
2749                         try = forwards;
2750                         try_lno = forwards_lno;
2751                 }
2752
2753         }
2754         return -1;
2755 }
2756
2757 static void remove_first_line(struct image *img)
2758 {
2759         img->buf += img->line[0].len;
2760         img->len -= img->line[0].len;
2761         img->line++;
2762         img->nr--;
2763 }
2764
2765 static void remove_last_line(struct image *img)
2766 {
2767         img->len -= img->line[--img->nr].len;
2768 }
2769
2770 /*
2771  * The change from "preimage" and "postimage" has been found to
2772  * apply at applied_pos (counts in line numbers) in "img".
2773  * Update "img" to remove "preimage" and replace it with "postimage".
2774  */
2775 static void update_image(struct apply_state *state,
2776                          struct image *img,
2777                          int applied_pos,
2778                          struct image *preimage,
2779                          struct image *postimage)
2780 {
2781         /*
2782          * remove the copy of preimage at offset in img
2783          * and replace it with postimage
2784          */
2785         int i, nr;
2786         size_t remove_count, insert_count, applied_at = 0;
2787         char *result;
2788         int preimage_limit;
2789
2790         /*
2791          * If we are removing blank lines at the end of img,
2792          * the preimage may extend beyond the end.
2793          * If that is the case, we must be careful only to
2794          * remove the part of the preimage that falls within
2795          * the boundaries of img. Initialize preimage_limit
2796          * to the number of lines in the preimage that falls
2797          * within the boundaries.
2798          */
2799         preimage_limit = preimage->nr;
2800         if (preimage_limit > img->nr - applied_pos)
2801                 preimage_limit = img->nr - applied_pos;
2802
2803         for (i = 0; i < applied_pos; i++)
2804                 applied_at += img->line[i].len;
2805
2806         remove_count = 0;
2807         for (i = 0; i < preimage_limit; i++)
2808                 remove_count += img->line[applied_pos + i].len;
2809         insert_count = postimage->len;
2810
2811         /* Adjust the contents */
2812         result = xmalloc(st_add3(st_sub(img->len, remove_count), insert_count, 1));
2813         memcpy(result, img->buf, applied_at);
2814         memcpy(result + applied_at, postimage->buf, postimage->len);
2815         memcpy(result + applied_at + postimage->len,
2816                img->buf + (applied_at + remove_count),
2817                img->len - (applied_at + remove_count));
2818         free(img->buf);
2819         img->buf = result;
2820         img->len += insert_count - remove_count;
2821         result[img->len] = '\0';
2822
2823         /* Adjust the line table */
2824         nr = img->nr + postimage->nr - preimage_limit;
2825         if (preimage_limit < postimage->nr) {
2826                 /*
2827                  * NOTE: this knows that we never call remove_first_line()
2828                  * on anything other than pre/post image.
2829                  */
2830                 REALLOC_ARRAY(img->line, nr);
2831                 img->line_allocated = img->line;
2832         }
2833         if (preimage_limit != postimage->nr)
2834                 MOVE_ARRAY(img->line + applied_pos + postimage->nr,
2835                            img->line + applied_pos + preimage_limit,
2836                            img->nr - (applied_pos + preimage_limit));
2837         COPY_ARRAY(img->line + applied_pos, postimage->line, postimage->nr);
2838         if (!state->allow_overlap)
2839                 for (i = 0; i < postimage->nr; i++)
2840                         img->line[applied_pos + i].flag |= LINE_PATCHED;
2841         img->nr = nr;
2842 }
2843
2844 /*
2845  * Use the patch-hunk text in "frag" to prepare two images (preimage and
2846  * postimage) for the hunk.  Find lines that match "preimage" in "img" and
2847  * replace the part of "img" with "postimage" text.
2848  */
2849 static int apply_one_fragment(struct apply_state *state,
2850                               struct image *img, struct fragment *frag,
2851                               int inaccurate_eof, unsigned ws_rule,
2852                               int nth_fragment)
2853 {
2854         int match_beginning, match_end;
2855         const char *patch = frag->patch;
2856         int size = frag->size;
2857         char *old, *oldlines;
2858         struct strbuf newlines;
2859         int new_blank_lines_at_end = 0;
2860         int found_new_blank_lines_at_end = 0;
2861         int hunk_linenr = frag->linenr;
2862         unsigned long leading, trailing;
2863         int pos, applied_pos;
2864         struct image preimage;
2865         struct image postimage;
2866
2867         memset(&preimage, 0, sizeof(preimage));
2868         memset(&postimage, 0, sizeof(postimage));
2869         oldlines = xmalloc(size);
2870         strbuf_init(&newlines, size);
2871
2872         old = oldlines;
2873         while (size > 0) {
2874                 char first;
2875                 int len = linelen(patch, size);
2876                 int plen;
2877                 int added_blank_line = 0;
2878                 int is_blank_context = 0;
2879                 size_t start;
2880
2881                 if (!len)
2882                         break;
2883
2884                 /*
2885                  * "plen" is how much of the line we should use for
2886                  * the actual patch data. Normally we just remove the
2887                  * first character on the line, but if the line is
2888                  * followed by "\ No newline", then we also remove the
2889                  * last one (which is the newline, of course).
2890                  */
2891                 plen = len - 1;
2892                 if (len < size && patch[len] == '\\')
2893                         plen--;
2894                 first = *patch;
2895                 if (state->apply_in_reverse) {
2896                         if (first == '-')
2897                                 first = '+';
2898                         else if (first == '+')
2899                                 first = '-';
2900                 }
2901
2902                 switch (first) {
2903                 case '\n':
2904                         /* Newer GNU diff, empty context line */
2905                         if (plen < 0)
2906                                 /* ... followed by '\No newline'; nothing */
2907                                 break;
2908                         *old++ = '\n';
2909                         strbuf_addch(&newlines, '\n');
2910                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
2911                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
2912                         is_blank_context = 1;
2913                         break;
2914                 case ' ':
2915                         if (plen && (ws_rule & WS_BLANK_AT_EOF) &&
2916                             ws_blank_line(patch + 1, plen, ws_rule))
2917                                 is_blank_context = 1;
2918                         /* fallthrough */
2919                 case '-':
2920                         memcpy(old, patch + 1, plen);
2921                         add_line_info(&preimage, old, plen,
2922                                       (first == ' ' ? LINE_COMMON : 0));
2923                         old += plen;
2924                         if (first == '-')
2925                                 break;
2926                         /* fallthrough */
2927                 case '+':
2928                         /* --no-add does not add new lines */
2929                         if (first == '+' && state->no_add)
2930                                 break;
2931
2932                         start = newlines.len;
2933                         if (first != '+' ||
2934                             !state->whitespace_error ||
2935                             state->ws_error_action != correct_ws_error) {
2936                                 strbuf_add(&newlines, patch + 1, plen);
2937                         }
2938                         else {
2939                                 ws_fix_copy(&newlines, patch + 1, plen, ws_rule, &state->applied_after_fixing_ws);
2940                         }
2941                         add_line_info(&postimage, newlines.buf + start, newlines.len - start,
2942                                       (first == '+' ? 0 : LINE_COMMON));
2943                         if (first == '+' &&
2944                             (ws_rule & WS_BLANK_AT_EOF) &&
2945                             ws_blank_line(patch + 1, plen, ws_rule))
2946                                 added_blank_line = 1;
2947                         break;
2948                 case '@': case '\\':
2949                         /* Ignore it, we already handled it */
2950                         break;
2951                 default:
2952                         if (state->apply_verbosity > verbosity_normal)
2953                                 error(_("invalid start of line: '%c'"), first);
2954                         applied_pos = -1;
2955                         goto out;
2956                 }
2957                 if (added_blank_line) {
2958                         if (!new_blank_lines_at_end)
2959                                 found_new_blank_lines_at_end = hunk_linenr;
2960                         new_blank_lines_at_end++;
2961                 }
2962                 else if (is_blank_context)
2963                         ;
2964                 else
2965                         new_blank_lines_at_end = 0;
2966                 patch += len;
2967                 size -= len;
2968                 hunk_linenr++;
2969         }
2970         if (inaccurate_eof &&
2971             old > oldlines && old[-1] == '\n' &&
2972             newlines.len > 0 && newlines.buf[newlines.len - 1] == '\n') {
2973                 old--;
2974                 strbuf_setlen(&newlines, newlines.len - 1);
2975         }
2976
2977         leading = frag->leading;
2978         trailing = frag->trailing;
2979
2980         /*
2981          * A hunk to change lines at the beginning would begin with
2982          * @@ -1,L +N,M @@
2983          * but we need to be careful.  -U0 that inserts before the second
2984          * line also has this pattern.
2985          *
2986          * And a hunk to add to an empty file would begin with
2987          * @@ -0,0 +N,M @@
2988          *
2989          * In other words, a hunk that is (frag->oldpos <= 1) with or
2990          * without leading context must match at the beginning.
2991          */
2992         match_beginning = (!frag->oldpos ||
2993                            (frag->oldpos == 1 && !state->unidiff_zero));
2994
2995         /*
2996          * A hunk without trailing lines must match at the end.
2997          * However, we simply cannot tell if a hunk must match end
2998          * from the lack of trailing lines if the patch was generated
2999          * with unidiff without any context.
3000          */
3001         match_end = !state->unidiff_zero && !trailing;
3002
3003         pos = frag->newpos ? (frag->newpos - 1) : 0;
3004         preimage.buf = oldlines;
3005         preimage.len = old - oldlines;
3006         postimage.buf = newlines.buf;
3007         postimage.len = newlines.len;
3008         preimage.line = preimage.line_allocated;
3009         postimage.line = postimage.line_allocated;
3010
3011         for (;;) {
3012
3013                 applied_pos = find_pos(state, img, &preimage, &postimage, pos,
3014                                        ws_rule, match_beginning, match_end);
3015
3016                 if (applied_pos >= 0)
3017                         break;
3018
3019                 /* Am I at my context limits? */
3020                 if ((leading <= state->p_context) && (trailing <= state->p_context))
3021                         break;
3022                 if (match_beginning || match_end) {
3023                         match_beginning = match_end = 0;
3024                         continue;
3025                 }
3026
3027                 /*
3028                  * Reduce the number of context lines; reduce both
3029                  * leading and trailing if they are equal otherwise
3030                  * just reduce the larger context.
3031                  */
3032                 if (leading >= trailing) {
3033                         remove_first_line(&preimage);
3034                         remove_first_line(&postimage);
3035                         pos--;
3036                         leading--;
3037                 }
3038                 if (trailing > leading) {
3039                         remove_last_line(&preimage);
3040                         remove_last_line(&postimage);
3041                         trailing--;
3042                 }
3043         }
3044
3045         if (applied_pos >= 0) {
3046                 if (new_blank_lines_at_end &&
3047                     preimage.nr + applied_pos >= img->nr &&
3048                     (ws_rule & WS_BLANK_AT_EOF) &&
3049                     state->ws_error_action != nowarn_ws_error) {
3050                         record_ws_error(state, WS_BLANK_AT_EOF, "+", 1,
3051                                         found_new_blank_lines_at_end);
3052                         if (state->ws_error_action == correct_ws_error) {
3053                                 while (new_blank_lines_at_end--)
3054                                         remove_last_line(&postimage);
3055                         }
3056                         /*
3057                          * We would want to prevent write_out_results()
3058                          * from taking place in apply_patch() that follows
3059                          * the callchain led us here, which is:
3060                          * apply_patch->check_patch_list->check_patch->
3061                          * apply_data->apply_fragments->apply_one_fragment
3062                          */
3063                         if (state->ws_error_action == die_on_ws_error)
3064                                 state->apply = 0;
3065                 }
3066
3067                 if (state->apply_verbosity > verbosity_normal && applied_pos != pos) {
3068                         int offset = applied_pos - pos;
3069                         if (state->apply_in_reverse)
3070                                 offset = 0 - offset;
3071                         fprintf_ln(stderr,
3072                                    Q_("Hunk #%d succeeded at %d (offset %d line).",
3073                                       "Hunk #%d succeeded at %d (offset %d lines).",
3074                                       offset),
3075                                    nth_fragment, applied_pos + 1, offset);
3076                 }
3077
3078                 /*
3079                  * Warn if it was necessary to reduce the number
3080                  * of context lines.
3081                  */
3082                 if ((leading != frag->leading ||
3083                      trailing != frag->trailing) && state->apply_verbosity > verbosity_silent)
3084                         fprintf_ln(stderr, _("Context reduced to (%ld/%ld)"
3085                                              " to apply fragment at %d"),
3086                                    leading, trailing, applied_pos+1);
3087                 update_image(state, img, applied_pos, &preimage, &postimage);
3088         } else {
3089                 if (state->apply_verbosity > verbosity_normal)
3090                         error(_("while searching for:\n%.*s"),
3091                               (int)(old - oldlines), oldlines);
3092         }
3093
3094 out:
3095         free(oldlines);
3096         strbuf_release(&newlines);
3097         free(preimage.line_allocated);
3098         free(postimage.line_allocated);
3099
3100         return (applied_pos < 0);
3101 }
3102
3103 static int apply_binary_fragment(struct apply_state *state,
3104                                  struct image *img,
3105                                  struct patch *patch)
3106 {
3107         struct fragment *fragment = patch->fragments;
3108         unsigned long len;
3109         void *dst;
3110
3111         if (!fragment)
3112                 return error(_("missing binary patch data for '%s'"),
3113                              patch->new_name ?
3114                              patch->new_name :
3115                              patch->old_name);
3116
3117         /* Binary patch is irreversible without the optional second hunk */
3118         if (state->apply_in_reverse) {
3119                 if (!fragment->next)
3120                         return error(_("cannot reverse-apply a binary patch "
3121                                        "without the reverse hunk to '%s'"),
3122                                      patch->new_name
3123                                      ? patch->new_name : patch->old_name);
3124                 fragment = fragment->next;
3125         }
3126         switch (fragment->binary_patch_method) {
3127         case BINARY_DELTA_DEFLATED:
3128                 dst = patch_delta(img->buf, img->len, fragment->patch,
3129                                   fragment->size, &len);
3130                 if (!dst)
3131                         return -1;
3132                 clear_image(img);
3133                 img->buf = dst;
3134                 img->len = len;
3135                 return 0;
3136         case BINARY_LITERAL_DEFLATED:
3137                 clear_image(img);
3138                 img->len = fragment->size;
3139                 img->buf = xmemdupz(fragment->patch, img->len);
3140                 return 0;
3141         }
3142         return -1;
3143 }
3144
3145 /*
3146  * Replace "img" with the result of applying the binary patch.
3147  * The binary patch data itself in patch->fragment is still kept
3148  * but the preimage prepared by the caller in "img" is freed here
3149  * or in the helper function apply_binary_fragment() this calls.
3150  */
3151 static int apply_binary(struct apply_state *state,
3152                         struct image *img,
3153                         struct patch *patch)
3154 {
3155         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3156         struct object_id oid;
3157
3158         /*
3159          * For safety, we require patch index line to contain
3160          * full 40-byte textual SHA1 for old and new, at least for now.
3161          */
3162         if (strlen(patch->old_sha1_prefix) != 40 ||
3163             strlen(patch->new_sha1_prefix) != 40 ||
3164             get_oid_hex(patch->old_sha1_prefix, &oid) ||
3165             get_oid_hex(patch->new_sha1_prefix, &oid))
3166                 return error(_("cannot apply binary patch to '%s' "
3167                                "without full index line"), name);
3168
3169         if (patch->old_name) {
3170                 /*
3171                  * See if the old one matches what the patch
3172                  * applies to.
3173                  */
3174                 hash_sha1_file(img->buf, img->len, blob_type, oid.hash);
3175                 if (strcmp(oid_to_hex(&oid), patch->old_sha1_prefix))
3176                         return error(_("the patch applies to '%s' (%s), "
3177                                        "which does not match the "
3178                                        "current contents."),
3179                                      name, oid_to_hex(&oid));
3180         }
3181         else {
3182                 /* Otherwise, the old one must be empty. */
3183                 if (img->len)
3184                         return error(_("the patch applies to an empty "
3185                                        "'%s' but it is not empty"), name);
3186         }
3187
3188         get_oid_hex(patch->new_sha1_prefix, &oid);
3189         if (is_null_oid(&oid)) {
3190                 clear_image(img);
3191                 return 0; /* deletion patch */
3192         }
3193
3194         if (has_sha1_file(oid.hash)) {
3195                 /* We already have the postimage */
3196                 enum object_type type;
3197                 unsigned long size;
3198                 char *result;
3199
3200                 result = read_sha1_file(oid.hash, &type, &size);
3201                 if (!result)
3202                         return error(_("the necessary postimage %s for "
3203                                        "'%s' cannot be read"),
3204                                      patch->new_sha1_prefix, name);
3205                 clear_image(img);
3206                 img->buf = result;
3207                 img->len = size;
3208         } else {
3209                 /*
3210                  * We have verified buf matches the preimage;
3211                  * apply the patch data to it, which is stored
3212                  * in the patch->fragments->{patch,size}.
3213                  */
3214                 if (apply_binary_fragment(state, img, patch))
3215                         return error(_("binary patch does not apply to '%s'"),
3216                                      name);
3217
3218                 /* verify that the result matches */
3219                 hash_sha1_file(img->buf, img->len, blob_type, oid.hash);
3220                 if (strcmp(oid_to_hex(&oid), patch->new_sha1_prefix))
3221                         return error(_("binary patch to '%s' creates incorrect result (expecting %s, got %s)"),
3222                                 name, patch->new_sha1_prefix, oid_to_hex(&oid));
3223         }
3224
3225         return 0;
3226 }
3227
3228 static int apply_fragments(struct apply_state *state, struct image *img, struct patch *patch)
3229 {
3230         struct fragment *frag = patch->fragments;
3231         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3232         unsigned ws_rule = patch->ws_rule;
3233         unsigned inaccurate_eof = patch->inaccurate_eof;
3234         int nth = 0;
3235
3236         if (patch->is_binary)
3237                 return apply_binary(state, img, patch);
3238
3239         while (frag) {
3240                 nth++;
3241                 if (apply_one_fragment(state, img, frag, inaccurate_eof, ws_rule, nth)) {
3242                         error(_("patch failed: %s:%ld"), name, frag->oldpos);
3243                         if (!state->apply_with_reject)
3244                                 return -1;
3245                         frag->rejected = 1;
3246                 }
3247                 frag = frag->next;
3248         }
3249         return 0;
3250 }
3251
3252 static int read_blob_object(struct strbuf *buf, const struct object_id *oid, unsigned mode)
3253 {
3254         if (S_ISGITLINK(mode)) {
3255                 strbuf_grow(buf, 100);
3256                 strbuf_addf(buf, "Subproject commit %s\n", oid_to_hex(oid));
3257         } else {
3258                 enum object_type type;
3259                 unsigned long sz;
3260                 char *result;
3261
3262                 result = read_sha1_file(oid->hash, &type, &sz);
3263                 if (!result)
3264                         return -1;
3265                 /* XXX read_sha1_file NUL-terminates */
3266                 strbuf_attach(buf, result, sz, sz + 1);
3267         }
3268         return 0;
3269 }
3270
3271 static int read_file_or_gitlink(const struct cache_entry *ce, struct strbuf *buf)
3272 {
3273         if (!ce)
3274                 return 0;
3275         return read_blob_object(buf, &ce->oid, ce->ce_mode);
3276 }
3277
3278 static struct patch *in_fn_table(struct apply_state *state, const char *name)
3279 {
3280         struct string_list_item *item;
3281
3282         if (name == NULL)
3283                 return NULL;
3284
3285         item = string_list_lookup(&state->fn_table, name);
3286         if (item != NULL)
3287                 return (struct patch *)item->util;
3288
3289         return NULL;
3290 }
3291
3292 /*
3293  * item->util in the filename table records the status of the path.
3294  * Usually it points at a patch (whose result records the contents
3295  * of it after applying it), but it could be PATH_WAS_DELETED for a
3296  * path that a previously applied patch has already removed, or
3297  * PATH_TO_BE_DELETED for a path that a later patch would remove.
3298  *
3299  * The latter is needed to deal with a case where two paths A and B
3300  * are swapped by first renaming A to B and then renaming B to A;
3301  * moving A to B should not be prevented due to presence of B as we
3302  * will remove it in a later patch.
3303  */
3304 #define PATH_TO_BE_DELETED ((struct patch *) -2)
3305 #define PATH_WAS_DELETED ((struct patch *) -1)
3306
3307 static int to_be_deleted(struct patch *patch)
3308 {
3309         return patch == PATH_TO_BE_DELETED;
3310 }
3311
3312 static int was_deleted(struct patch *patch)
3313 {
3314         return patch == PATH_WAS_DELETED;
3315 }
3316
3317 static void add_to_fn_table(struct apply_state *state, struct patch *patch)
3318 {
3319         struct string_list_item *item;
3320
3321         /*
3322          * Always add new_name unless patch is a deletion
3323          * This should cover the cases for normal diffs,
3324          * file creations and copies
3325          */
3326         if (patch->new_name != NULL) {
3327                 item = string_list_insert(&state->fn_table, patch->new_name);
3328                 item->util = patch;
3329         }
3330
3331         /*
3332          * store a failure on rename/deletion cases because
3333          * later chunks shouldn't patch old names
3334          */
3335         if ((patch->new_name == NULL) || (patch->is_rename)) {
3336                 item = string_list_insert(&state->fn_table, patch->old_name);
3337                 item->util = PATH_WAS_DELETED;
3338         }
3339 }
3340
3341 static void prepare_fn_table(struct apply_state *state, struct patch *patch)
3342 {
3343         /*
3344          * store information about incoming file deletion
3345          */
3346         while (patch) {
3347                 if ((patch->new_name == NULL) || (patch->is_rename)) {
3348                         struct string_list_item *item;
3349                         item = string_list_insert(&state->fn_table, patch->old_name);
3350                         item->util = PATH_TO_BE_DELETED;
3351                 }
3352                 patch = patch->next;
3353         }
3354 }
3355
3356 static int checkout_target(struct index_state *istate,
3357                            struct cache_entry *ce, struct stat *st)
3358 {
3359         struct checkout costate = CHECKOUT_INIT;
3360
3361         costate.refresh_cache = 1;
3362         costate.istate = istate;
3363         if (checkout_entry(ce, &costate, NULL) || lstat(ce->name, st))
3364                 return error(_("cannot checkout %s"), ce->name);
3365         return 0;
3366 }
3367
3368 static struct patch *previous_patch(struct apply_state *state,
3369                                     struct patch *patch,
3370                                     int *gone)
3371 {
3372         struct patch *previous;
3373
3374         *gone = 0;
3375         if (patch->is_copy || patch->is_rename)
3376                 return NULL; /* "git" patches do not depend on the order */
3377
3378         previous = in_fn_table(state, patch->old_name);
3379         if (!previous)
3380                 return NULL;
3381
3382         if (to_be_deleted(previous))
3383                 return NULL; /* the deletion hasn't happened yet */
3384
3385         if (was_deleted(previous))
3386                 *gone = 1;
3387
3388         return previous;
3389 }
3390
3391 static int verify_index_match(const struct cache_entry *ce, struct stat *st)
3392 {
3393         if (S_ISGITLINK(ce->ce_mode)) {
3394                 if (!S_ISDIR(st->st_mode))
3395                         return -1;
3396                 return 0;
3397         }
3398         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
3399 }
3400
3401 #define SUBMODULE_PATCH_WITHOUT_INDEX 1
3402
3403 static int load_patch_target(struct apply_state *state,
3404                              struct strbuf *buf,
3405                              const struct cache_entry *ce,
3406                              struct stat *st,
3407                              struct patch *patch,
3408                              const char *name,
3409                              unsigned expected_mode)
3410 {
3411         if (state->cached || state->check_index) {
3412                 if (read_file_or_gitlink(ce, buf))
3413                         return error(_("failed to read %s"), name);
3414         } else if (name) {
3415                 if (S_ISGITLINK(expected_mode)) {
3416                         if (ce)
3417                                 return read_file_or_gitlink(ce, buf);
3418                         else
3419                                 return SUBMODULE_PATCH_WITHOUT_INDEX;
3420                 } else if (has_symlink_leading_path(name, strlen(name))) {
3421                         return error(_("reading from '%s' beyond a symbolic link"), name);
3422                 } else {
3423                         if (read_old_data(st, patch, name, buf))
3424                                 return error(_("failed to read %s"), name);
3425                 }
3426         }
3427         return 0;
3428 }
3429
3430 /*
3431  * We are about to apply "patch"; populate the "image" with the
3432  * current version we have, from the working tree or from the index,
3433  * depending on the situation e.g. --cached/--index.  If we are
3434  * applying a non-git patch that incrementally updates the tree,
3435  * we read from the result of a previous diff.
3436  */
3437 static int load_preimage(struct apply_state *state,
3438                          struct image *image,
3439                          struct patch *patch, struct stat *st,
3440                          const struct cache_entry *ce)
3441 {
3442         struct strbuf buf = STRBUF_INIT;
3443         size_t len;
3444         char *img;
3445         struct patch *previous;
3446         int status;
3447
3448         previous = previous_patch(state, patch, &status);
3449         if (status)
3450                 return error(_("path %s has been renamed/deleted"),
3451                              patch->old_name);
3452         if (previous) {
3453                 /* We have a patched copy in memory; use that. */
3454                 strbuf_add(&buf, previous->result, previous->resultsize);
3455         } else {
3456                 status = load_patch_target(state, &buf, ce, st, patch,
3457                                            patch->old_name, patch->old_mode);
3458                 if (status < 0)
3459                         return status;
3460                 else if (status == SUBMODULE_PATCH_WITHOUT_INDEX) {
3461                         /*
3462                          * There is no way to apply subproject
3463                          * patch without looking at the index.
3464                          * NEEDSWORK: shouldn't this be flagged
3465                          * as an error???
3466                          */
3467                         free_fragment_list(patch->fragments);
3468                         patch->fragments = NULL;
3469                 } else if (status) {
3470                         return error(_("failed to read %s"), patch->old_name);
3471                 }
3472         }
3473
3474         img = strbuf_detach(&buf, &len);
3475         prepare_image(image, img, len, !patch->is_binary);
3476         return 0;
3477 }
3478
3479 static int three_way_merge(struct image *image,
3480                            char *path,
3481                            const struct object_id *base,
3482                            const struct object_id *ours,
3483                            const struct object_id *theirs)
3484 {
3485         mmfile_t base_file, our_file, their_file;
3486         mmbuffer_t result = { NULL };
3487         int status;
3488
3489         read_mmblob(&base_file, base);
3490         read_mmblob(&our_file, ours);
3491         read_mmblob(&their_file, theirs);
3492         status = ll_merge(&result, path,
3493                           &base_file, "base",
3494                           &our_file, "ours",
3495                           &their_file, "theirs", NULL);
3496         free(base_file.ptr);
3497         free(our_file.ptr);
3498         free(their_file.ptr);
3499         if (status < 0 || !result.ptr) {
3500                 free(result.ptr);
3501                 return -1;
3502         }
3503         clear_image(image);
3504         image->buf = result.ptr;
3505         image->len = result.size;
3506
3507         return status;
3508 }
3509
3510 /*
3511  * When directly falling back to add/add three-way merge, we read from
3512  * the current contents of the new_name.  In no cases other than that
3513  * this function will be called.
3514  */
3515 static int load_current(struct apply_state *state,
3516                         struct image *image,
3517                         struct patch *patch)
3518 {
3519         struct strbuf buf = STRBUF_INIT;
3520         int status, pos;
3521         size_t len;
3522         char *img;
3523         struct stat st;
3524         struct cache_entry *ce;
3525         char *name = patch->new_name;
3526         unsigned mode = patch->new_mode;
3527
3528         if (!patch->is_new)
3529                 die("BUG: patch to %s is not a creation", patch->old_name);
3530
3531         pos = cache_name_pos(name, strlen(name));
3532         if (pos < 0)
3533                 return error(_("%s: does not exist in index"), name);
3534         ce = active_cache[pos];
3535         if (lstat(name, &st)) {
3536                 if (errno != ENOENT)
3537                         return error_errno("%s", name);
3538                 if (checkout_target(&the_index, ce, &st))
3539                         return -1;
3540         }
3541         if (verify_index_match(ce, &st))
3542                 return error(_("%s: does not match index"), name);
3543
3544         status = load_patch_target(state, &buf, ce, &st, patch, name, mode);
3545         if (status < 0)
3546                 return status;
3547         else if (status)
3548                 return -1;
3549         img = strbuf_detach(&buf, &len);
3550         prepare_image(image, img, len, !patch->is_binary);
3551         return 0;
3552 }
3553
3554 static int try_threeway(struct apply_state *state,
3555                         struct image *image,
3556                         struct patch *patch,
3557                         struct stat *st,
3558                         const struct cache_entry *ce)
3559 {
3560         struct object_id pre_oid, post_oid, our_oid;
3561         struct strbuf buf = STRBUF_INIT;
3562         size_t len;
3563         int status;
3564         char *img;
3565         struct image tmp_image;
3566
3567         /* No point falling back to 3-way merge in these cases */
3568         if (patch->is_delete ||
3569             S_ISGITLINK(patch->old_mode) || S_ISGITLINK(patch->new_mode))
3570                 return -1;
3571
3572         /* Preimage the patch was prepared for */
3573         if (patch->is_new)
3574                 write_sha1_file("", 0, blob_type, pre_oid.hash);
3575         else if (get_oid(patch->old_sha1_prefix, &pre_oid) ||
3576                  read_blob_object(&buf, &pre_oid, patch->old_mode))
3577                 return error(_("repository lacks the necessary blob to fall back on 3-way merge."));
3578
3579         if (state->apply_verbosity > verbosity_silent)
3580                 fprintf(stderr, _("Falling back to three-way merge...\n"));
3581
3582         img = strbuf_detach(&buf, &len);
3583         prepare_image(&tmp_image, img, len, 1);
3584         /* Apply the patch to get the post image */
3585         if (apply_fragments(state, &tmp_image, patch) < 0) {
3586                 clear_image(&tmp_image);
3587                 return -1;
3588         }
3589         /* post_oid is theirs */
3590         write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, post_oid.hash);
3591         clear_image(&tmp_image);
3592
3593         /* our_oid is ours */
3594         if (patch->is_new) {
3595                 if (load_current(state, &tmp_image, patch))
3596                         return error(_("cannot read the current contents of '%s'"),
3597                                      patch->new_name);
3598         } else {
3599                 if (load_preimage(state, &tmp_image, patch, st, ce))
3600                         return error(_("cannot read the current contents of '%s'"),
3601                                      patch->old_name);
3602         }
3603         write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, our_oid.hash);
3604         clear_image(&tmp_image);
3605
3606         /* in-core three-way merge between post and our using pre as base */
3607         status = three_way_merge(image, patch->new_name,
3608                                  &pre_oid, &our_oid, &post_oid);
3609         if (status < 0) {
3610                 if (state->apply_verbosity > verbosity_silent)
3611                         fprintf(stderr,
3612                                 _("Failed to fall back on three-way merge...\n"));
3613                 return status;
3614         }
3615
3616         if (status) {
3617                 patch->conflicted_threeway = 1;
3618                 if (patch->is_new)
3619                         oidclr(&patch->threeway_stage[0]);
3620                 else
3621                         oidcpy(&patch->threeway_stage[0], &pre_oid);
3622                 oidcpy(&patch->threeway_stage[1], &our_oid);
3623                 oidcpy(&patch->threeway_stage[2], &post_oid);
3624                 if (state->apply_verbosity > verbosity_silent)
3625                         fprintf(stderr,
3626                                 _("Applied patch to '%s' with conflicts.\n"),
3627                                 patch->new_name);
3628         } else {
3629                 if (state->apply_verbosity > verbosity_silent)
3630                         fprintf(stderr,
3631                                 _("Applied patch to '%s' cleanly.\n"),
3632                                 patch->new_name);
3633         }
3634         return 0;
3635 }
3636
3637 static int apply_data(struct apply_state *state, struct patch *patch,
3638                       struct stat *st, const struct cache_entry *ce)
3639 {
3640         struct image image;
3641
3642         if (load_preimage(state, &image, patch, st, ce) < 0)
3643                 return -1;
3644
3645         if (patch->direct_to_threeway ||
3646             apply_fragments(state, &image, patch) < 0) {
3647                 /* Note: with --reject, apply_fragments() returns 0 */
3648                 if (!state->threeway || try_threeway(state, &image, patch, st, ce) < 0)
3649                         return -1;
3650         }
3651         patch->result = image.buf;
3652         patch->resultsize = image.len;
3653         add_to_fn_table(state, patch);
3654         free(image.line_allocated);
3655
3656         if (0 < patch->is_delete && patch->resultsize)
3657                 return error(_("removal patch leaves file contents"));
3658
3659         return 0;
3660 }
3661
3662 /*
3663  * If "patch" that we are looking at modifies or deletes what we have,
3664  * we would want it not to lose any local modification we have, either
3665  * in the working tree or in the index.
3666  *
3667  * This also decides if a non-git patch is a creation patch or a
3668  * modification to an existing empty file.  We do not check the state
3669  * of the current tree for a creation patch in this function; the caller
3670  * check_patch() separately makes sure (and errors out otherwise) that
3671  * the path the patch creates does not exist in the current tree.
3672  */
3673 static int check_preimage(struct apply_state *state,
3674                           struct patch *patch,
3675                           struct cache_entry **ce,
3676                           struct stat *st)
3677 {
3678         const char *old_name = patch->old_name;
3679         struct patch *previous = NULL;
3680         int stat_ret = 0, status;
3681         unsigned st_mode = 0;
3682
3683         if (!old_name)
3684                 return 0;
3685
3686         assert(patch->is_new <= 0);
3687         previous = previous_patch(state, patch, &status);
3688
3689         if (status)
3690                 return error(_("path %s has been renamed/deleted"), old_name);
3691         if (previous) {
3692                 st_mode = previous->new_mode;
3693         } else if (!state->cached) {
3694                 stat_ret = lstat(old_name, st);
3695                 if (stat_ret && errno != ENOENT)
3696                         return error_errno("%s", old_name);
3697         }
3698
3699         if (state->check_index && !previous) {
3700                 int pos = cache_name_pos(old_name, strlen(old_name));
3701                 if (pos < 0) {
3702                         if (patch->is_new < 0)
3703                                 goto is_new;
3704                         return error(_("%s: does not exist in index"), old_name);
3705                 }
3706                 *ce = active_cache[pos];
3707                 if (stat_ret < 0) {
3708                         if (checkout_target(&the_index, *ce, st))
3709                                 return -1;
3710                 }
3711                 if (!state->cached && verify_index_match(*ce, st))
3712                         return error(_("%s: does not match index"), old_name);
3713                 if (state->cached)
3714                         st_mode = (*ce)->ce_mode;
3715         } else if (stat_ret < 0) {
3716                 if (patch->is_new < 0)
3717                         goto is_new;
3718                 return error_errno("%s", old_name);
3719         }
3720
3721         if (!state->cached && !previous)
3722                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
3723
3724         if (patch->is_new < 0)
3725                 patch->is_new = 0;
3726         if (!patch->old_mode)
3727                 patch->old_mode = st_mode;
3728         if ((st_mode ^ patch->old_mode) & S_IFMT)
3729                 return error(_("%s: wrong type"), old_name);
3730         if (st_mode != patch->old_mode)
3731                 warning(_("%s has type %o, expected %o"),
3732                         old_name, st_mode, patch->old_mode);
3733         if (!patch->new_mode && !patch->is_delete)
3734                 patch->new_mode = st_mode;
3735         return 0;
3736
3737  is_new:
3738         patch->is_new = 1;
3739         patch->is_delete = 0;
3740         FREE_AND_NULL(patch->old_name);
3741         return 0;
3742 }
3743
3744
3745 #define EXISTS_IN_INDEX 1
3746 #define EXISTS_IN_WORKTREE 2
3747
3748 static int check_to_create(struct apply_state *state,
3749                            const char *new_name,
3750                            int ok_if_exists)
3751 {
3752         struct stat nst;
3753
3754         if (state->check_index &&
3755             cache_name_pos(new_name, strlen(new_name)) >= 0 &&
3756             !ok_if_exists)
3757                 return EXISTS_IN_INDEX;
3758         if (state->cached)
3759                 return 0;
3760
3761         if (!lstat(new_name, &nst)) {
3762                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
3763                         return 0;
3764                 /*
3765                  * A leading component of new_name might be a symlink
3766                  * that is going to be removed with this patch, but
3767                  * still pointing at somewhere that has the path.
3768                  * In such a case, path "new_name" does not exist as
3769                  * far as git is concerned.
3770                  */
3771                 if (has_symlink_leading_path(new_name, strlen(new_name)))
3772                         return 0;
3773
3774                 return EXISTS_IN_WORKTREE;
3775         } else if (!is_missing_file_error(errno)) {
3776                 return error_errno("%s", new_name);
3777         }
3778         return 0;
3779 }
3780
3781 static uintptr_t register_symlink_changes(struct apply_state *state,
3782                                           const char *path,
3783                                           uintptr_t what)
3784 {
3785         struct string_list_item *ent;
3786
3787         ent = string_list_lookup(&state->symlink_changes, path);
3788         if (!ent) {
3789                 ent = string_list_insert(&state->symlink_changes, path);
3790                 ent->util = (void *)0;
3791         }
3792         ent->util = (void *)(what | ((uintptr_t)ent->util));
3793         return (uintptr_t)ent->util;
3794 }
3795
3796 static uintptr_t check_symlink_changes(struct apply_state *state, const char *path)
3797 {
3798         struct string_list_item *ent;
3799
3800         ent = string_list_lookup(&state->symlink_changes, path);
3801         if (!ent)
3802                 return 0;
3803         return (uintptr_t)ent->util;
3804 }
3805
3806 static void prepare_symlink_changes(struct apply_state *state, struct patch *patch)
3807 {
3808         for ( ; patch; patch = patch->next) {
3809                 if ((patch->old_name && S_ISLNK(patch->old_mode)) &&
3810                     (patch->is_rename || patch->is_delete))
3811                         /* the symlink at patch->old_name is removed */
3812                         register_symlink_changes(state, patch->old_name, APPLY_SYMLINK_GOES_AWAY);
3813
3814                 if (patch->new_name && S_ISLNK(patch->new_mode))
3815                         /* the symlink at patch->new_name is created or remains */
3816                         register_symlink_changes(state, patch->new_name, APPLY_SYMLINK_IN_RESULT);
3817         }
3818 }
3819
3820 static int path_is_beyond_symlink_1(struct apply_state *state, struct strbuf *name)
3821 {
3822         do {
3823                 unsigned int change;
3824
3825                 while (--name->len && name->buf[name->len] != '/')
3826                         ; /* scan backwards */
3827                 if (!name->len)
3828                         break;
3829                 name->buf[name->len] = '\0';
3830                 change = check_symlink_changes(state, name->buf);
3831                 if (change & APPLY_SYMLINK_IN_RESULT)
3832                         return 1;
3833                 if (change & APPLY_SYMLINK_GOES_AWAY)
3834                         /*
3835                          * This cannot be "return 0", because we may
3836                          * see a new one created at a higher level.
3837                          */
3838                         continue;
3839
3840                 /* otherwise, check the preimage */
3841                 if (state->check_index) {
3842                         struct cache_entry *ce;
3843
3844                         ce = cache_file_exists(name->buf, name->len, ignore_case);
3845                         if (ce && S_ISLNK(ce->ce_mode))
3846                                 return 1;
3847                 } else {
3848                         struct stat st;
3849                         if (!lstat(name->buf, &st) && S_ISLNK(st.st_mode))
3850                                 return 1;
3851                 }
3852         } while (1);
3853         return 0;
3854 }
3855
3856 static int path_is_beyond_symlink(struct apply_state *state, const char *name_)
3857 {
3858         int ret;
3859         struct strbuf name = STRBUF_INIT;
3860
3861         assert(*name_ != '\0');
3862         strbuf_addstr(&name, name_);
3863         ret = path_is_beyond_symlink_1(state, &name);
3864         strbuf_release(&name);
3865
3866         return ret;
3867 }
3868
3869 static int check_unsafe_path(struct patch *patch)
3870 {
3871         const char *old_name = NULL;
3872         const char *new_name = NULL;
3873         if (patch->is_delete)
3874                 old_name = patch->old_name;
3875         else if (!patch->is_new && !patch->is_copy)
3876                 old_name = patch->old_name;
3877         if (!patch->is_delete)
3878                 new_name = patch->new_name;
3879
3880         if (old_name && !verify_path(old_name))
3881                 return error(_("invalid path '%s'"), old_name);
3882         if (new_name && !verify_path(new_name))
3883                 return error(_("invalid path '%s'"), new_name);
3884         return 0;
3885 }
3886
3887 /*
3888  * Check and apply the patch in-core; leave the result in patch->result
3889  * for the caller to write it out to the final destination.
3890  */
3891 static int check_patch(struct apply_state *state, struct patch *patch)
3892 {
3893         struct stat st;
3894         const char *old_name = patch->old_name;
3895         const char *new_name = patch->new_name;
3896         const char *name = old_name ? old_name : new_name;
3897         struct cache_entry *ce = NULL;
3898         struct patch *tpatch;
3899         int ok_if_exists;
3900         int status;
3901
3902         patch->rejected = 1; /* we will drop this after we succeed */
3903
3904         status = check_preimage(state, patch, &ce, &st);
3905         if (status)
3906                 return status;
3907         old_name = patch->old_name;
3908
3909         /*
3910          * A type-change diff is always split into a patch to delete
3911          * old, immediately followed by a patch to create new (see
3912          * diff.c::run_diff()); in such a case it is Ok that the entry
3913          * to be deleted by the previous patch is still in the working
3914          * tree and in the index.
3915          *
3916          * A patch to swap-rename between A and B would first rename A
3917          * to B and then rename B to A.  While applying the first one,
3918          * the presence of B should not stop A from getting renamed to
3919          * B; ask to_be_deleted() about the later rename.  Removal of
3920          * B and rename from A to B is handled the same way by asking
3921          * was_deleted().
3922          */
3923         if ((tpatch = in_fn_table(state, new_name)) &&
3924             (was_deleted(tpatch) || to_be_deleted(tpatch)))
3925                 ok_if_exists = 1;
3926         else
3927                 ok_if_exists = 0;
3928
3929         if (new_name &&
3930             ((0 < patch->is_new) || patch->is_rename || patch->is_copy)) {
3931                 int err = check_to_create(state, new_name, ok_if_exists);
3932
3933                 if (err && state->threeway) {
3934                         patch->direct_to_threeway = 1;
3935                 } else switch (err) {
3936                 case 0:
3937                         break; /* happy */
3938                 case EXISTS_IN_INDEX:
3939                         return error(_("%s: already exists in index"), new_name);
3940                         break;
3941                 case EXISTS_IN_WORKTREE:
3942                         return error(_("%s: already exists in working directory"),
3943                                      new_name);
3944                 default:
3945                         return err;
3946                 }
3947
3948                 if (!patch->new_mode) {
3949                         if (0 < patch->is_new)
3950                                 patch->new_mode = S_IFREG | 0644;
3951                         else
3952                                 patch->new_mode = patch->old_mode;
3953                 }
3954         }
3955
3956         if (new_name && old_name) {
3957                 int same = !strcmp(old_name, new_name);
3958                 if (!patch->new_mode)
3959                         patch->new_mode = patch->old_mode;
3960                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT) {
3961                         if (same)
3962                                 return error(_("new mode (%o) of %s does not "
3963                                                "match old mode (%o)"),
3964                                         patch->new_mode, new_name,
3965                                         patch->old_mode);
3966                         else
3967                                 return error(_("new mode (%o) of %s does not "
3968                                                "match old mode (%o) of %s"),
3969                                         patch->new_mode, new_name,
3970                                         patch->old_mode, old_name);
3971                 }
3972         }
3973
3974         if (!state->unsafe_paths && check_unsafe_path(patch))
3975                 return -128;
3976
3977         /*
3978          * An attempt to read from or delete a path that is beyond a
3979          * symbolic link will be prevented by load_patch_target() that
3980          * is called at the beginning of apply_data() so we do not
3981          * have to worry about a patch marked with "is_delete" bit
3982          * here.  We however need to make sure that the patch result
3983          * is not deposited to a path that is beyond a symbolic link
3984          * here.
3985          */
3986         if (!patch->is_delete && path_is_beyond_symlink(state, patch->new_name))
3987                 return error(_("affected file '%s' is beyond a symbolic link"),
3988                              patch->new_name);
3989
3990         if (apply_data(state, patch, &st, ce) < 0)
3991                 return error(_("%s: patch does not apply"), name);
3992         patch->rejected = 0;
3993         return 0;
3994 }
3995
3996 static int check_patch_list(struct apply_state *state, struct patch *patch)
3997 {
3998         int err = 0;
3999
4000         prepare_symlink_changes(state, patch);
4001         prepare_fn_table(state, patch);
4002         while (patch) {
4003                 int res;
4004                 if (state->apply_verbosity > verbosity_normal)
4005                         say_patch_name(stderr,
4006                                        _("Checking patch %s..."), patch);
4007                 res = check_patch(state, patch);
4008                 if (res == -128)
4009                         return -128;
4010                 err |= res;
4011                 patch = patch->next;
4012         }
4013         return err;
4014 }
4015
4016 static int read_apply_cache(struct apply_state *state)
4017 {
4018         if (state->index_file)
4019                 return read_cache_from(state->index_file);
4020         else
4021                 return read_cache();
4022 }
4023
4024 /* This function tries to read the object name from the current index */
4025 static int get_current_oid(struct apply_state *state, const char *path,
4026                            struct object_id *oid)
4027 {
4028         int pos;
4029
4030         if (read_apply_cache(state) < 0)
4031                 return -1;
4032         pos = cache_name_pos(path, strlen(path));
4033         if (pos < 0)
4034                 return -1;
4035         oidcpy(oid, &active_cache[pos]->oid);
4036         return 0;
4037 }
4038
4039 static int preimage_oid_in_gitlink_patch(struct patch *p, struct object_id *oid)
4040 {
4041         /*
4042          * A usable gitlink patch has only one fragment (hunk) that looks like:
4043          * @@ -1 +1 @@
4044          * -Subproject commit <old sha1>
4045          * +Subproject commit <new sha1>
4046          * or
4047          * @@ -1 +0,0 @@
4048          * -Subproject commit <old sha1>
4049          * for a removal patch.
4050          */
4051         struct fragment *hunk = p->fragments;
4052         static const char heading[] = "-Subproject commit ";
4053         char *preimage;
4054
4055         if (/* does the patch have only one hunk? */
4056             hunk && !hunk->next &&
4057             /* is its preimage one line? */
4058             hunk->oldpos == 1 && hunk->oldlines == 1 &&
4059             /* does preimage begin with the heading? */
4060             (preimage = memchr(hunk->patch, '\n', hunk->size)) != NULL &&
4061             starts_with(++preimage, heading) &&
4062             /* does it record full SHA-1? */
4063             !get_oid_hex(preimage + sizeof(heading) - 1, oid) &&
4064             preimage[sizeof(heading) + GIT_SHA1_HEXSZ - 1] == '\n' &&
4065             /* does the abbreviated name on the index line agree with it? */
4066             starts_with(preimage + sizeof(heading) - 1, p->old_sha1_prefix))
4067                 return 0; /* it all looks fine */
4068
4069         /* we may have full object name on the index line */
4070         return get_oid_hex(p->old_sha1_prefix, oid);
4071 }
4072
4073 /* Build an index that contains the just the files needed for a 3way merge */
4074 static int build_fake_ancestor(struct apply_state *state, struct patch *list)
4075 {
4076         struct patch *patch;
4077         struct index_state result = { NULL };
4078         static struct lock_file lock;
4079         int res;
4080
4081         /* Once we start supporting the reverse patch, it may be
4082          * worth showing the new sha1 prefix, but until then...
4083          */
4084         for (patch = list; patch; patch = patch->next) {
4085                 struct object_id oid;
4086                 struct cache_entry *ce;
4087                 const char *name;
4088
4089                 name = patch->old_name ? patch->old_name : patch->new_name;
4090                 if (0 < patch->is_new)
4091                         continue;
4092
4093                 if (S_ISGITLINK(patch->old_mode)) {
4094                         if (!preimage_oid_in_gitlink_patch(patch, &oid))
4095                                 ; /* ok, the textual part looks sane */
4096                         else
4097                                 return error(_("sha1 information is lacking or "
4098                                                "useless for submodule %s"), name);
4099                 } else if (!get_oid_blob(patch->old_sha1_prefix, &oid)) {
4100                         ; /* ok */
4101                 } else if (!patch->lines_added && !patch->lines_deleted) {
4102                         /* mode-only change: update the current */
4103                         if (get_current_oid(state, patch->old_name, &oid))
4104                                 return error(_("mode change for %s, which is not "
4105                                                "in current HEAD"), name);
4106                 } else
4107                         return error(_("sha1 information is lacking or useless "
4108                                        "(%s)."), name);
4109
4110                 ce = make_cache_entry(patch->old_mode, oid.hash, name, 0, 0);
4111                 if (!ce)
4112                         return error(_("make_cache_entry failed for path '%s'"),
4113                                      name);
4114                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD)) {
4115                         free(ce);
4116                         return error(_("could not add %s to temporary index"),
4117                                      name);
4118                 }
4119         }
4120
4121         hold_lock_file_for_update(&lock, state->fake_ancestor, LOCK_DIE_ON_ERROR);
4122         res = write_locked_index(&result, &lock, COMMIT_LOCK);
4123         discard_index(&result);
4124
4125         if (res)
4126                 return error(_("could not write temporary index to %s"),
4127                              state->fake_ancestor);
4128
4129         return 0;
4130 }
4131
4132 static void stat_patch_list(struct apply_state *state, struct patch *patch)
4133 {
4134         int files, adds, dels;
4135
4136         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
4137                 files++;
4138                 adds += patch->lines_added;
4139                 dels += patch->lines_deleted;
4140                 show_stats(state, patch);
4141         }
4142
4143         print_stat_summary(stdout, files, adds, dels);
4144 }
4145
4146 static void numstat_patch_list(struct apply_state *state,
4147                                struct patch *patch)
4148 {
4149         for ( ; patch; patch = patch->next) {
4150                 const char *name;
4151                 name = patch->new_name ? patch->new_name : patch->old_name;
4152                 if (patch->is_binary)
4153                         printf("-\t-\t");
4154                 else
4155                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
4156                 write_name_quoted(name, stdout, state->line_termination);
4157         }
4158 }
4159
4160 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
4161 {
4162         if (mode)
4163                 printf(" %s mode %06o %s\n", newdelete, mode, name);
4164         else
4165                 printf(" %s %s\n", newdelete, name);
4166 }
4167
4168 static void show_mode_change(struct patch *p, int show_name)
4169 {
4170         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
4171                 if (show_name)
4172                         printf(" mode change %06o => %06o %s\n",
4173                                p->old_mode, p->new_mode, p->new_name);
4174                 else
4175                         printf(" mode change %06o => %06o\n",
4176                                p->old_mode, p->new_mode);
4177         }
4178 }
4179
4180 static void show_rename_copy(struct patch *p)
4181 {
4182         const char *renamecopy = p->is_rename ? "rename" : "copy";
4183         const char *old, *new;
4184
4185         /* Find common prefix */
4186         old = p->old_name;
4187         new = p->new_name;
4188         while (1) {
4189                 const char *slash_old, *slash_new;
4190                 slash_old = strchr(old, '/');
4191                 slash_new = strchr(new, '/');
4192                 if (!slash_old ||
4193                     !slash_new ||
4194                     slash_old - old != slash_new - new ||
4195                     memcmp(old, new, slash_new - new))
4196                         break;
4197                 old = slash_old + 1;
4198                 new = slash_new + 1;
4199         }
4200         /* p->old_name thru old is the common prefix, and old and new
4201          * through the end of names are renames
4202          */
4203         if (old != p->old_name)
4204                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
4205                        (int)(old - p->old_name), p->old_name,
4206                        old, new, p->score);
4207         else
4208                 printf(" %s %s => %s (%d%%)\n", renamecopy,
4209                        p->old_name, p->new_name, p->score);
4210         show_mode_change(p, 0);
4211 }
4212
4213 static void summary_patch_list(struct patch *patch)
4214 {
4215         struct patch *p;
4216
4217         for (p = patch; p; p = p->next) {
4218                 if (p->is_new)
4219                         show_file_mode_name("create", p->new_mode, p->new_name);
4220                 else if (p->is_delete)
4221                         show_file_mode_name("delete", p->old_mode, p->old_name);
4222                 else {
4223                         if (p->is_rename || p->is_copy)
4224                                 show_rename_copy(p);
4225                         else {
4226                                 if (p->score) {
4227                                         printf(" rewrite %s (%d%%)\n",
4228                                                p->new_name, p->score);
4229                                         show_mode_change(p, 0);
4230                                 }
4231                                 else
4232                                         show_mode_change(p, 1);
4233                         }
4234                 }
4235         }
4236 }
4237
4238 static void patch_stats(struct apply_state *state, struct patch *patch)
4239 {
4240         int lines = patch->lines_added + patch->lines_deleted;
4241
4242         if (lines > state->max_change)
4243                 state->max_change = lines;
4244         if (patch->old_name) {
4245                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
4246                 if (!len)
4247                         len = strlen(patch->old_name);
4248                 if (len > state->max_len)
4249                         state->max_len = len;
4250         }
4251         if (patch->new_name) {
4252                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
4253                 if (!len)
4254                         len = strlen(patch->new_name);
4255                 if (len > state->max_len)
4256                         state->max_len = len;
4257         }
4258 }
4259
4260 static int remove_file(struct apply_state *state, struct patch *patch, int rmdir_empty)
4261 {
4262         if (state->update_index) {
4263                 if (remove_file_from_cache(patch->old_name) < 0)
4264                         return error(_("unable to remove %s from index"), patch->old_name);
4265         }
4266         if (!state->cached) {
4267                 if (!remove_or_warn(patch->old_mode, patch->old_name) && rmdir_empty) {
4268                         remove_path(patch->old_name);
4269                 }
4270         }
4271         return 0;
4272 }
4273
4274 static int add_index_file(struct apply_state *state,
4275                           const char *path,
4276                           unsigned mode,
4277                           void *buf,
4278                           unsigned long size)
4279 {
4280         struct stat st;
4281         struct cache_entry *ce;
4282         int namelen = strlen(path);
4283         unsigned ce_size = cache_entry_size(namelen);
4284
4285         if (!state->update_index)
4286                 return 0;
4287
4288         ce = xcalloc(1, ce_size);
4289         memcpy(ce->name, path, namelen);
4290         ce->ce_mode = create_ce_mode(mode);
4291         ce->ce_flags = create_ce_flags(0);
4292         ce->ce_namelen = namelen;
4293         if (S_ISGITLINK(mode)) {
4294                 const char *s;
4295
4296                 if (!skip_prefix(buf, "Subproject commit ", &s) ||
4297                     get_oid_hex(s, &ce->oid)) {
4298                         free(ce);
4299                        return error(_("corrupt patch for submodule %s"), path);
4300                 }
4301         } else {
4302                 if (!state->cached) {
4303                         if (lstat(path, &st) < 0) {
4304                                 free(ce);
4305                                 return error_errno(_("unable to stat newly "
4306                                                      "created file '%s'"),
4307                                                    path);
4308                         }
4309                         fill_stat_cache_info(ce, &st);
4310                 }
4311                 if (write_sha1_file(buf, size, blob_type, ce->oid.hash) < 0) {
4312                         free(ce);
4313                         return error(_("unable to create backing store "
4314                                        "for newly created file %s"), path);
4315                 }
4316         }
4317         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4318                 free(ce);
4319                 return error(_("unable to add cache entry for %s"), path);
4320         }
4321
4322         return 0;
4323 }
4324
4325 /*
4326  * Returns:
4327  *  -1 if an unrecoverable error happened
4328  *   0 if everything went well
4329  *   1 if a recoverable error happened
4330  */
4331 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
4332 {
4333         int fd, res;
4334         struct strbuf nbuf = STRBUF_INIT;
4335
4336         if (S_ISGITLINK(mode)) {
4337                 struct stat st;
4338                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
4339                         return 0;
4340                 return !!mkdir(path, 0777);
4341         }
4342
4343         if (has_symlinks && S_ISLNK(mode))
4344                 /* Although buf:size is counted string, it also is NUL
4345                  * terminated.
4346                  */
4347                 return !!symlink(buf, path);
4348
4349         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
4350         if (fd < 0)
4351                 return 1;
4352
4353         if (convert_to_working_tree(path, buf, size, &nbuf)) {
4354                 size = nbuf.len;
4355                 buf  = nbuf.buf;
4356         }
4357
4358         res = write_in_full(fd, buf, size) < 0;
4359         if (res)
4360                 error_errno(_("failed to write to '%s'"), path);
4361         strbuf_release(&nbuf);
4362
4363         if (close(fd) < 0 && !res)
4364                 return error_errno(_("closing file '%s'"), path);
4365
4366         return res ? -1 : 0;
4367 }
4368
4369 /*
4370  * We optimistically assume that the directories exist,
4371  * which is true 99% of the time anyway. If they don't,
4372  * we create them and try again.
4373  *
4374  * Returns:
4375  *   -1 on error
4376  *   0 otherwise
4377  */
4378 static int create_one_file(struct apply_state *state,
4379                            char *path,
4380                            unsigned mode,
4381                            const char *buf,
4382                            unsigned long size)
4383 {
4384         int res;
4385
4386         if (state->cached)
4387                 return 0;
4388
4389         res = try_create_file(path, mode, buf, size);
4390         if (res < 0)
4391                 return -1;
4392         if (!res)
4393                 return 0;
4394
4395         if (errno == ENOENT) {
4396                 if (safe_create_leading_directories(path))
4397                         return 0;
4398                 res = try_create_file(path, mode, buf, size);
4399                 if (res < 0)
4400                         return -1;
4401                 if (!res)
4402                         return 0;
4403         }
4404
4405         if (errno == EEXIST || errno == EACCES) {
4406                 /* We may be trying to create a file where a directory
4407                  * used to be.
4408                  */
4409                 struct stat st;
4410                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
4411                         errno = EEXIST;
4412         }
4413
4414         if (errno == EEXIST) {
4415                 unsigned int nr = getpid();
4416
4417                 for (;;) {
4418                         char newpath[PATH_MAX];
4419                         mksnpath(newpath, sizeof(newpath), "%s~%u", path, nr);
4420                         res = try_create_file(newpath, mode, buf, size);
4421                         if (res < 0)
4422                                 return -1;
4423                         if (!res) {
4424                                 if (!rename(newpath, path))
4425                                         return 0;
4426                                 unlink_or_warn(newpath);
4427                                 break;
4428                         }
4429                         if (errno != EEXIST)
4430                                 break;
4431                         ++nr;
4432                 }
4433         }
4434         return error_errno(_("unable to write file '%s' mode %o"),
4435                            path, mode);
4436 }
4437
4438 static int add_conflicted_stages_file(struct apply_state *state,
4439                                        struct patch *patch)
4440 {
4441         int stage, namelen;
4442         unsigned ce_size, mode;
4443         struct cache_entry *ce;
4444
4445         if (!state->update_index)
4446                 return 0;
4447         namelen = strlen(patch->new_name);
4448         ce_size = cache_entry_size(namelen);
4449         mode = patch->new_mode ? patch->new_mode : (S_IFREG | 0644);
4450
4451         remove_file_from_cache(patch->new_name);
4452         for (stage = 1; stage < 4; stage++) {
4453                 if (is_null_oid(&patch->threeway_stage[stage - 1]))
4454                         continue;
4455                 ce = xcalloc(1, ce_size);
4456                 memcpy(ce->name, patch->new_name, namelen);
4457                 ce->ce_mode = create_ce_mode(mode);
4458                 ce->ce_flags = create_ce_flags(stage);
4459                 ce->ce_namelen = namelen;
4460                 oidcpy(&ce->oid, &patch->threeway_stage[stage - 1]);
4461                 if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4462                         free(ce);
4463                         return error(_("unable to add cache entry for %s"),
4464                                      patch->new_name);
4465                 }
4466         }
4467
4468         return 0;
4469 }
4470
4471 static int create_file(struct apply_state *state, struct patch *patch)
4472 {
4473         char *path = patch->new_name;
4474         unsigned mode = patch->new_mode;
4475         unsigned long size = patch->resultsize;
4476         char *buf = patch->result;
4477
4478         if (!mode)
4479                 mode = S_IFREG | 0644;
4480         if (create_one_file(state, path, mode, buf, size))
4481                 return -1;
4482
4483         if (patch->conflicted_threeway)
4484                 return add_conflicted_stages_file(state, patch);
4485         else
4486                 return add_index_file(state, path, mode, buf, size);
4487 }
4488
4489 /* phase zero is to remove, phase one is to create */
4490 static int write_out_one_result(struct apply_state *state,
4491                                 struct patch *patch,
4492                                 int phase)
4493 {
4494         if (patch->is_delete > 0) {
4495                 if (phase == 0)
4496                         return remove_file(state, patch, 1);
4497                 return 0;
4498         }
4499         if (patch->is_new > 0 || patch->is_copy) {
4500                 if (phase == 1)
4501                         return create_file(state, patch);
4502                 return 0;
4503         }
4504         /*
4505          * Rename or modification boils down to the same
4506          * thing: remove the old, write the new
4507          */
4508         if (phase == 0)
4509                 return remove_file(state, patch, patch->is_rename);
4510         if (phase == 1)
4511                 return create_file(state, patch);
4512         return 0;
4513 }
4514
4515 static int write_out_one_reject(struct apply_state *state, struct patch *patch)
4516 {
4517         FILE *rej;
4518         char namebuf[PATH_MAX];
4519         struct fragment *frag;
4520         int cnt = 0;
4521         struct strbuf sb = STRBUF_INIT;
4522
4523         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
4524                 if (!frag->rejected)
4525                         continue;
4526                 cnt++;
4527         }
4528
4529         if (!cnt) {
4530                 if (state->apply_verbosity > verbosity_normal)
4531                         say_patch_name(stderr,
4532                                        _("Applied patch %s cleanly."), patch);
4533                 return 0;
4534         }
4535
4536         /* This should not happen, because a removal patch that leaves
4537          * contents are marked "rejected" at the patch level.
4538          */
4539         if (!patch->new_name)
4540                 die(_("internal error"));
4541
4542         /* Say this even without --verbose */
4543         strbuf_addf(&sb, Q_("Applying patch %%s with %d reject...",
4544                             "Applying patch %%s with %d rejects...",
4545                             cnt),
4546                     cnt);
4547         if (state->apply_verbosity > verbosity_silent)
4548                 say_patch_name(stderr, sb.buf, patch);
4549         strbuf_release(&sb);
4550
4551         cnt = strlen(patch->new_name);
4552         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
4553                 cnt = ARRAY_SIZE(namebuf) - 5;
4554                 warning(_("truncating .rej filename to %.*s.rej"),
4555                         cnt - 1, patch->new_name);
4556         }
4557         memcpy(namebuf, patch->new_name, cnt);
4558         memcpy(namebuf + cnt, ".rej", 5);
4559
4560         rej = fopen(namebuf, "w");
4561         if (!rej)
4562                 return error_errno(_("cannot open %s"), namebuf);
4563
4564         /* Normal git tools never deal with .rej, so do not pretend
4565          * this is a git patch by saying --git or giving extended
4566          * headers.  While at it, maybe please "kompare" that wants
4567          * the trailing TAB and some garbage at the end of line ;-).
4568          */
4569         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
4570                 patch->new_name, patch->new_name);
4571         for (cnt = 1, frag = patch->fragments;
4572              frag;
4573              cnt++, frag = frag->next) {
4574                 if (!frag->rejected) {
4575                         if (state->apply_verbosity > verbosity_silent)
4576                                 fprintf_ln(stderr, _("Hunk #%d applied cleanly."), cnt);
4577                         continue;
4578                 }
4579                 if (state->apply_verbosity > verbosity_silent)
4580                         fprintf_ln(stderr, _("Rejected hunk #%d."), cnt);
4581                 fprintf(rej, "%.*s", frag->size, frag->patch);
4582                 if (frag->patch[frag->size-1] != '\n')
4583                         fputc('\n', rej);
4584         }
4585         fclose(rej);
4586         return -1;
4587 }
4588
4589 /*
4590  * Returns:
4591  *  -1 if an error happened
4592  *   0 if the patch applied cleanly
4593  *   1 if the patch did not apply cleanly
4594  */
4595 static int write_out_results(struct apply_state *state, struct patch *list)
4596 {
4597         int phase;
4598         int errs = 0;
4599         struct patch *l;
4600         struct string_list cpath = STRING_LIST_INIT_DUP;
4601
4602         for (phase = 0; phase < 2; phase++) {
4603                 l = list;
4604                 while (l) {
4605                         if (l->rejected)
4606                                 errs = 1;
4607                         else {
4608                                 if (write_out_one_result(state, l, phase)) {
4609                                         string_list_clear(&cpath, 0);
4610                                         return -1;
4611                                 }
4612                                 if (phase == 1) {
4613                                         if (write_out_one_reject(state, l))
4614                                                 errs = 1;
4615                                         if (l->conflicted_threeway) {
4616                                                 string_list_append(&cpath, l->new_name);
4617                                                 errs = 1;
4618                                         }
4619                                 }
4620                         }
4621                         l = l->next;
4622                 }
4623         }
4624
4625         if (cpath.nr) {
4626                 struct string_list_item *item;
4627
4628                 string_list_sort(&cpath);
4629                 if (state->apply_verbosity > verbosity_silent) {
4630                         for_each_string_list_item(item, &cpath)
4631                                 fprintf(stderr, "U %s\n", item->string);
4632                 }
4633                 string_list_clear(&cpath, 0);
4634
4635                 rerere(0);
4636         }
4637
4638         return errs;
4639 }
4640
4641 /*
4642  * Try to apply a patch.
4643  *
4644  * Returns:
4645  *  -128 if a bad error happened (like patch unreadable)
4646  *  -1 if patch did not apply and user cannot deal with it
4647  *   0 if the patch applied
4648  *   1 if the patch did not apply but user might fix it
4649  */
4650 static int apply_patch(struct apply_state *state,
4651                        int fd,
4652                        const char *filename,
4653                        int options)
4654 {
4655         size_t offset;
4656         struct strbuf buf = STRBUF_INIT; /* owns the patch text */
4657         struct patch *list = NULL, **listp = &list;
4658         int skipped_patch = 0;
4659         int res = 0;
4660
4661         state->patch_input_file = filename;
4662         if (read_patch_file(&buf, fd) < 0)
4663                 return -128;
4664         offset = 0;
4665         while (offset < buf.len) {
4666                 struct patch *patch;
4667                 int nr;
4668
4669                 patch = xcalloc(1, sizeof(*patch));
4670                 patch->inaccurate_eof = !!(options & APPLY_OPT_INACCURATE_EOF);
4671                 patch->recount =  !!(options & APPLY_OPT_RECOUNT);
4672                 nr = parse_chunk(state, buf.buf + offset, buf.len - offset, patch);
4673                 if (nr < 0) {
4674                         free_patch(patch);
4675                         if (nr == -128) {
4676                                 res = -128;
4677                                 goto end;
4678                         }
4679                         break;
4680                 }
4681                 if (state->apply_in_reverse)
4682                         reverse_patches(patch);
4683                 if (use_patch(state, patch)) {
4684                         patch_stats(state, patch);
4685                         *listp = patch;
4686                         listp = &patch->next;
4687                 }
4688                 else {
4689                         if (state->apply_verbosity > verbosity_normal)
4690                                 say_patch_name(stderr, _("Skipped patch '%s'."), patch);
4691                         free_patch(patch);
4692                         skipped_patch++;
4693                 }
4694                 offset += nr;
4695         }
4696
4697         if (!list && !skipped_patch) {
4698                 error(_("unrecognized input"));
4699                 res = -128;
4700                 goto end;
4701         }
4702
4703         if (state->whitespace_error && (state->ws_error_action == die_on_ws_error))
4704                 state->apply = 0;
4705
4706         state->update_index = state->check_index && state->apply;
4707         if (state->update_index && !is_lock_file_locked(&state->lock_file)) {
4708                 if (state->index_file)
4709                         hold_lock_file_for_update(&state->lock_file,
4710                                                   state->index_file,
4711                                                   LOCK_DIE_ON_ERROR);
4712                 else
4713                         hold_locked_index(&state->lock_file, LOCK_DIE_ON_ERROR);
4714         }
4715
4716         if (state->check_index && read_apply_cache(state) < 0) {
4717                 error(_("unable to read index file"));
4718                 res = -128;
4719                 goto end;
4720         }
4721
4722         if (state->check || state->apply) {
4723                 int r = check_patch_list(state, list);
4724                 if (r == -128) {
4725                         res = -128;
4726                         goto end;
4727                 }
4728                 if (r < 0 && !state->apply_with_reject) {
4729                         res = -1;
4730                         goto end;
4731                 }
4732         }
4733
4734         if (state->apply) {
4735                 int write_res = write_out_results(state, list);
4736                 if (write_res < 0) {
4737                         res = -128;
4738                         goto end;
4739                 }
4740                 if (write_res > 0) {
4741                         /* with --3way, we still need to write the index out */
4742                         res = state->apply_with_reject ? -1 : 1;
4743                         goto end;
4744                 }
4745         }
4746
4747         if (state->fake_ancestor &&
4748             build_fake_ancestor(state, list)) {
4749                 res = -128;
4750                 goto end;
4751         }
4752
4753         if (state->diffstat && state->apply_verbosity > verbosity_silent)
4754                 stat_patch_list(state, list);
4755
4756         if (state->numstat && state->apply_verbosity > verbosity_silent)
4757                 numstat_patch_list(state, list);
4758
4759         if (state->summary && state->apply_verbosity > verbosity_silent)
4760                 summary_patch_list(list);
4761
4762 end:
4763         free_patch_list(list);
4764         strbuf_release(&buf);
4765         string_list_clear(&state->fn_table, 0);
4766         return res;
4767 }
4768
4769 static int apply_option_parse_exclude(const struct option *opt,
4770                                       const char *arg, int unset)
4771 {
4772         struct apply_state *state = opt->value;
4773         add_name_limit(state, arg, 1);
4774         return 0;
4775 }
4776
4777 static int apply_option_parse_include(const struct option *opt,
4778                                       const char *arg, int unset)
4779 {
4780         struct apply_state *state = opt->value;
4781         add_name_limit(state, arg, 0);
4782         state->has_include = 1;
4783         return 0;
4784 }
4785
4786 static int apply_option_parse_p(const struct option *opt,
4787                                 const char *arg,
4788                                 int unset)
4789 {
4790         struct apply_state *state = opt->value;
4791         state->p_value = atoi(arg);
4792         state->p_value_known = 1;
4793         return 0;
4794 }
4795
4796 static int apply_option_parse_space_change(const struct option *opt,
4797                                            const char *arg, int unset)
4798 {
4799         struct apply_state *state = opt->value;
4800         if (unset)
4801                 state->ws_ignore_action = ignore_ws_none;
4802         else
4803                 state->ws_ignore_action = ignore_ws_change;
4804         return 0;
4805 }
4806
4807 static int apply_option_parse_whitespace(const struct option *opt,
4808                                          const char *arg, int unset)
4809 {
4810         struct apply_state *state = opt->value;
4811         state->whitespace_option = arg;
4812         if (parse_whitespace_option(state, arg))
4813                 exit(1);
4814         return 0;
4815 }
4816
4817 static int apply_option_parse_directory(const struct option *opt,
4818                                         const char *arg, int unset)
4819 {
4820         struct apply_state *state = opt->value;
4821         strbuf_reset(&state->root);
4822         strbuf_addstr(&state->root, arg);
4823         strbuf_complete(&state->root, '/');
4824         return 0;
4825 }
4826
4827 int apply_all_patches(struct apply_state *state,
4828                       int argc,
4829                       const char **argv,
4830                       int options)
4831 {
4832         int i;
4833         int res;
4834         int errs = 0;
4835         int read_stdin = 1;
4836
4837         for (i = 0; i < argc; i++) {
4838                 const char *arg = argv[i];
4839                 char *to_free = NULL;
4840                 int fd;
4841
4842                 if (!strcmp(arg, "-")) {
4843                         res = apply_patch(state, 0, "<stdin>", options);
4844                         if (res < 0)
4845                                 goto end;
4846                         errs |= res;
4847                         read_stdin = 0;
4848                         continue;
4849                 } else
4850                         arg = to_free = prefix_filename(state->prefix, arg);
4851
4852                 fd = open(arg, O_RDONLY);
4853                 if (fd < 0) {
4854                         error(_("can't open patch '%s': %s"), arg, strerror(errno));
4855                         res = -128;
4856                         free(to_free);
4857                         goto end;
4858                 }
4859                 read_stdin = 0;
4860                 set_default_whitespace_mode(state);
4861                 res = apply_patch(state, fd, arg, options);
4862                 close(fd);
4863                 free(to_free);
4864                 if (res < 0)
4865                         goto end;
4866                 errs |= res;
4867         }
4868         set_default_whitespace_mode(state);
4869         if (read_stdin) {
4870                 res = apply_patch(state, 0, "<stdin>", options);
4871                 if (res < 0)
4872                         goto end;
4873                 errs |= res;
4874         }
4875
4876         if (state->whitespace_error) {
4877                 if (state->squelch_whitespace_errors &&
4878                     state->squelch_whitespace_errors < state->whitespace_error) {
4879                         int squelched =
4880                                 state->whitespace_error - state->squelch_whitespace_errors;
4881                         warning(Q_("squelched %d whitespace error",
4882                                    "squelched %d whitespace errors",
4883                                    squelched),
4884                                 squelched);
4885                 }
4886                 if (state->ws_error_action == die_on_ws_error) {
4887                         error(Q_("%d line adds whitespace errors.",
4888                                  "%d lines add whitespace errors.",
4889                                  state->whitespace_error),
4890                               state->whitespace_error);
4891                         res = -128;
4892                         goto end;
4893                 }
4894                 if (state->applied_after_fixing_ws && state->apply)
4895                         warning(Q_("%d line applied after"
4896                                    " fixing whitespace errors.",
4897                                    "%d lines applied after"
4898                                    " fixing whitespace errors.",
4899                                    state->applied_after_fixing_ws),
4900                                 state->applied_after_fixing_ws);
4901                 else if (state->whitespace_error)
4902                         warning(Q_("%d line adds whitespace errors.",
4903                                    "%d lines add whitespace errors.",
4904                                    state->whitespace_error),
4905                                 state->whitespace_error);
4906         }
4907
4908         if (state->update_index) {
4909                 res = write_locked_index(&the_index, &state->lock_file, COMMIT_LOCK);
4910                 if (res) {
4911                         error(_("Unable to write new index file"));
4912                         res = -128;
4913                         goto end;
4914                 }
4915         }
4916
4917         res = !!errs;
4918
4919 end:
4920         rollback_lock_file(&state->lock_file);
4921
4922         if (state->apply_verbosity <= verbosity_silent) {
4923                 set_error_routine(state->saved_error_routine);
4924                 set_warn_routine(state->saved_warn_routine);
4925         }
4926
4927         if (res > -1)
4928                 return res;
4929         return (res == -1 ? 1 : 128);
4930 }
4931
4932 int apply_parse_options(int argc, const char **argv,
4933                         struct apply_state *state,
4934                         int *force_apply, int *options,
4935                         const char * const *apply_usage)
4936 {
4937         struct option builtin_apply_options[] = {
4938                 { OPTION_CALLBACK, 0, "exclude", state, N_("path"),
4939                         N_("don't apply changes matching the given path"),
4940                         0, apply_option_parse_exclude },
4941                 { OPTION_CALLBACK, 0, "include", state, N_("path"),
4942                         N_("apply changes matching the given path"),
4943                         0, apply_option_parse_include },
4944                 { OPTION_CALLBACK, 'p', NULL, state, N_("num"),
4945                         N_("remove <num> leading slashes from traditional diff paths"),
4946                         0, apply_option_parse_p },
4947                 OPT_BOOL(0, "no-add", &state->no_add,
4948                         N_("ignore additions made by the patch")),
4949                 OPT_BOOL(0, "stat", &state->diffstat,
4950                         N_("instead of applying the patch, output diffstat for the input")),
4951                 OPT_NOOP_NOARG(0, "allow-binary-replacement"),
4952                 OPT_NOOP_NOARG(0, "binary"),
4953                 OPT_BOOL(0, "numstat", &state->numstat,
4954                         N_("show number of added and deleted lines in decimal notation")),
4955                 OPT_BOOL(0, "summary", &state->summary,
4956                         N_("instead of applying the patch, output a summary for the input")),
4957                 OPT_BOOL(0, "check", &state->check,
4958                         N_("instead of applying the patch, see if the patch is applicable")),
4959                 OPT_BOOL(0, "index", &state->check_index,
4960                         N_("make sure the patch is applicable to the current index")),
4961                 OPT_BOOL(0, "cached", &state->cached,
4962                         N_("apply a patch without touching the working tree")),
4963                 OPT_BOOL(0, "unsafe-paths", &state->unsafe_paths,
4964                         N_("accept a patch that touches outside the working area")),
4965                 OPT_BOOL(0, "apply", force_apply,
4966                         N_("also apply the patch (use with --stat/--summary/--check)")),
4967                 OPT_BOOL('3', "3way", &state->threeway,
4968                          N_( "attempt three-way merge if a patch does not apply")),
4969                 OPT_FILENAME(0, "build-fake-ancestor", &state->fake_ancestor,
4970                         N_("build a temporary index based on embedded index information")),
4971                 /* Think twice before adding "--nul" synonym to this */
4972                 OPT_SET_INT('z', NULL, &state->line_termination,
4973                         N_("paths are separated with NUL character"), '\0'),
4974                 OPT_INTEGER('C', NULL, &state->p_context,
4975                                 N_("ensure at least <n> lines of context match")),
4976                 { OPTION_CALLBACK, 0, "whitespace", state, N_("action"),
4977                         N_("detect new or modified lines that have whitespace errors"),
4978                         0, apply_option_parse_whitespace },
4979                 { OPTION_CALLBACK, 0, "ignore-space-change", state, NULL,
4980                         N_("ignore changes in whitespace when finding context"),
4981                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4982                 { OPTION_CALLBACK, 0, "ignore-whitespace", state, NULL,
4983                         N_("ignore changes in whitespace when finding context"),
4984                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4985                 OPT_BOOL('R', "reverse", &state->apply_in_reverse,
4986                         N_("apply the patch in reverse")),
4987                 OPT_BOOL(0, "unidiff-zero", &state->unidiff_zero,
4988                         N_("don't expect at least one line of context")),
4989                 OPT_BOOL(0, "reject", &state->apply_with_reject,
4990                         N_("leave the rejected hunks in corresponding *.rej files")),
4991                 OPT_BOOL(0, "allow-overlap", &state->allow_overlap,
4992                         N_("allow overlapping hunks")),
4993                 OPT__VERBOSE(&state->apply_verbosity, N_("be verbose")),
4994                 OPT_BIT(0, "inaccurate-eof", options,
4995                         N_("tolerate incorrectly detected missing new-line at the end of file"),
4996                         APPLY_OPT_INACCURATE_EOF),
4997                 OPT_BIT(0, "recount", options,
4998                         N_("do not trust the line counts in the hunk headers"),
4999                         APPLY_OPT_RECOUNT),
5000                 { OPTION_CALLBACK, 0, "directory", state, N_("root"),
5001                         N_("prepend <root> to all filenames"),
5002                         0, apply_option_parse_directory },
5003                 OPT_END()
5004         };
5005
5006         return parse_options(argc, argv, state->prefix, builtin_apply_options, apply_usage, 0);
5007 }