git.oblomov.eu Git - git/blob - add-patch.c

   1 #include "cache.h"
   2 #include "add-interactive.h"
   3 #include "strbuf.h"
   4 #include "run-command.h"
   5 #include "strvec.h"
   6 #include "pathspec.h"
   7 #include "color.h"
   8 #include "diff.h"
   9 #include "compat/terminal.h"
  10 #include "prompt.h"
  11
  12 enum prompt_mode_type {
  13         PROMPT_MODE_CHANGE = 0, PROMPT_DELETION, PROMPT_ADDITION, PROMPT_HUNK,
  14         PROMPT_MODE_MAX, /* must be last */
  15 };
  16
  17 struct patch_mode {
  18         /*
  19          * The magic constant 4 is chosen such that all patch modes
  20          * provide enough space for three command-line arguments followed by a
  21          * trailing `NULL`.
  22          */
  23         const char *diff_cmd[4], *apply_args[4], *apply_check_args[4];
  24         unsigned is_reverse:1, index_only:1, apply_for_checkout:1;
  25         const char *prompt_mode[PROMPT_MODE_MAX];
  26         const char *edit_hunk_hint, *help_patch_text;
  27 };
  28
  29 static struct patch_mode patch_mode_add = {
  30         .diff_cmd = { "diff-files", NULL },
  31         .apply_args = { "--cached", NULL },
  32         .apply_check_args = { "--cached", NULL },
  33         .prompt_mode = {
  34                 N_("Stage mode change [y,n,q,a,d%s,?]? "),
  35                 N_("Stage deletion [y,n,q,a,d%s,?]? "),
  36                 N_("Stage addition [y,n,q,a,d%s,?]? "),
  37                 N_("Stage this hunk [y,n,q,a,d%s,?]? ")
  38         },
  39         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
  40                              "will immediately be marked for staging."),
  41         .help_patch_text =
  42                 N_("y - stage this hunk\n"
  43                    "n - do not stage this hunk\n"
  44                    "q - quit; do not stage this hunk or any of the remaining "
  45                         "ones\n"
  46                    "a - stage this hunk and all later hunks in the file\n"
  47                    "d - do not stage this hunk or any of the later hunks in "
  48                         "the file\n")
  49 };
  50
  51 static struct patch_mode patch_mode_stash = {
  52         .diff_cmd = { "diff-index", "HEAD", NULL },
  53         .apply_args = { "--cached", NULL },
  54         .apply_check_args = { "--cached", NULL },
  55         .prompt_mode = {
  56                 N_("Stash mode change [y,n,q,a,d%s,?]? "),
  57                 N_("Stash deletion [y,n,q,a,d%s,?]? "),
  58                 N_("Stash addition [y,n,q,a,d%s,?]? "),
  59                 N_("Stash this hunk [y,n,q,a,d%s,?]? "),
  60         },
  61         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
  62                              "will immediately be marked for stashing."),
  63         .help_patch_text =
  64                 N_("y - stash this hunk\n"
  65                    "n - do not stash this hunk\n"
  66                    "q - quit; do not stash this hunk or any of the remaining "
  67                         "ones\n"
  68                    "a - stash this hunk and all later hunks in the file\n"
  69                    "d - do not stash this hunk or any of the later hunks in "
  70                         "the file\n"),
  71 };
  72
  73 static struct patch_mode patch_mode_reset_head = {
  74         .diff_cmd = { "diff-index", "--cached", NULL },
  75         .apply_args = { "-R", "--cached", NULL },
  76         .apply_check_args = { "-R", "--cached", NULL },
  77         .is_reverse = 1,
  78         .index_only = 1,
  79         .prompt_mode = {
  80                 N_("Unstage mode change [y,n,q,a,d%s,?]? "),
  81                 N_("Unstage deletion [y,n,q,a,d%s,?]? "),
  82                 N_("Unstage addition [y,n,q,a,d%s,?]? "),
  83                 N_("Unstage this hunk [y,n,q,a,d%s,?]? "),
  84         },
  85         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
  86                              "will immediately be marked for unstaging."),
  87         .help_patch_text =
  88                 N_("y - unstage this hunk\n"
  89                    "n - do not unstage this hunk\n"
  90                    "q - quit; do not unstage this hunk or any of the remaining "
  91                         "ones\n"
  92                    "a - unstage this hunk and all later hunks in the file\n"
  93                    "d - do not unstage this hunk or any of the later hunks in "
  94                         "the file\n"),
  95 };
  96
  97 static struct patch_mode patch_mode_reset_nothead = {
  98         .diff_cmd = { "diff-index", "-R", "--cached", NULL },
  99         .apply_args = { "--cached", NULL },
 100         .apply_check_args = { "--cached", NULL },
 101         .index_only = 1,
 102         .prompt_mode = {
 103                 N_("Apply mode change to index [y,n,q,a,d%s,?]? "),
 104                 N_("Apply deletion to index [y,n,q,a,d%s,?]? "),
 105                 N_("Apply addition to index [y,n,q,a,d%s,?]? "),
 106                 N_("Apply this hunk to index [y,n,q,a,d%s,?]? "),
 107         },
 108         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
 109                              "will immediately be marked for applying."),
 110         .help_patch_text =
 111                 N_("y - apply this hunk to index\n"
 112                    "n - do not apply this hunk to index\n"
 113                    "q - quit; do not apply this hunk or any of the remaining "
 114                         "ones\n"
 115                    "a - apply this hunk and all later hunks in the file\n"
 116                    "d - do not apply this hunk or any of the later hunks in "
 117                         "the file\n"),
 118 };
 119
 120 static struct patch_mode patch_mode_checkout_index = {
 121         .diff_cmd = { "diff-files", NULL },
 122         .apply_args = { "-R", NULL },
 123         .apply_check_args = { "-R", NULL },
 124         .is_reverse = 1,
 125         .prompt_mode = {
 126                 N_("Discard mode change from worktree [y,n,q,a,d%s,?]? "),
 127                 N_("Discard deletion from worktree [y,n,q,a,d%s,?]? "),
 128                 N_("Discard addition from worktree [y,n,q,a,d%s,?]? "),
 129                 N_("Discard this hunk from worktree [y,n,q,a,d%s,?]? "),
 130         },
 131         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
 132                              "will immediately be marked for discarding."),
 133         .help_patch_text =
 134                 N_("y - discard this hunk from worktree\n"
 135                    "n - do not discard this hunk from worktree\n"
 136                    "q - quit; do not discard this hunk or any of the remaining "
 137                         "ones\n"
 138                    "a - discard this hunk and all later hunks in the file\n"
 139                    "d - do not discard this hunk or any of the later hunks in "
 140                         "the file\n"),
 141 };
 142
 143 static struct patch_mode patch_mode_checkout_head = {
 144         .diff_cmd = { "diff-index", NULL },
 145         .apply_for_checkout = 1,
 146         .apply_check_args = { "-R", NULL },
 147         .is_reverse = 1,
 148         .prompt_mode = {
 149                 N_("Discard mode change from index and worktree [y,n,q,a,d%s,?]? "),
 150                 N_("Discard deletion from index and worktree [y,n,q,a,d%s,?]? "),
 151                 N_("Discard addition from index and worktree [y,n,q,a,d%s,?]? "),
 152                 N_("Discard this hunk from index and worktree [y,n,q,a,d%s,?]? "),
 153         },
 154         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
 155                              "will immediately be marked for discarding."),
 156         .help_patch_text =
 157                 N_("y - discard this hunk from index and worktree\n"
 158                    "n - do not discard this hunk from index and worktree\n"
 159                    "q - quit; do not discard this hunk or any of the remaining "
 160                         "ones\n"
 161                    "a - discard this hunk and all later hunks in the file\n"
 162                    "d - do not discard this hunk or any of the later hunks in "
 163                         "the file\n"),
 164 };
 165
 166 static struct patch_mode patch_mode_checkout_nothead = {
 167         .diff_cmd = { "diff-index", "-R", NULL },
 168         .apply_for_checkout = 1,
 169         .apply_check_args = { NULL },
 170         .prompt_mode = {
 171                 N_("Apply mode change to index and worktree [y,n,q,a,d%s,?]? "),
 172                 N_("Apply deletion to index and worktree [y,n,q,a,d%s,?]? "),
 173                 N_("Apply addition to index and worktree [y,n,q,a,d%s,?]? "),
 174                 N_("Apply this hunk to index and worktree [y,n,q,a,d%s,?]? "),
 175         },
 176         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
 177                              "will immediately be marked for applying."),
 178         .help_patch_text =
 179                 N_("y - apply this hunk to index and worktree\n"
 180                    "n - do not apply this hunk to index and worktree\n"
 181                    "q - quit; do not apply this hunk or any of the remaining "
 182                         "ones\n"
 183                    "a - apply this hunk and all later hunks in the file\n"
 184                    "d - do not apply this hunk or any of the later hunks in "
 185                         "the file\n"),
 186 };
 187
 188 static struct patch_mode patch_mode_worktree_head = {
 189         .diff_cmd = { "diff-index", NULL },
 190         .apply_args = { "-R", NULL },
 191         .apply_check_args = { "-R", NULL },
 192         .is_reverse = 1,
 193         .prompt_mode = {
 194                 N_("Discard mode change from index and worktree [y,n,q,a,d%s,?]? "),
 195                 N_("Discard deletion from index and worktree [y,n,q,a,d%s,?]? "),
 196                 N_("Discard addition from index and worktree [y,n,q,a,d%s,?]? "),
 197                 N_("Discard this hunk from index and worktree [y,n,q,a,d%s,?]? "),
 198         },
 199         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
 200                              "will immediately be marked for discarding."),
 201         .help_patch_text =
 202                 N_("y - discard this hunk from worktree\n"
 203                    "n - do not discard this hunk from worktree\n"
 204                    "q - quit; do not discard this hunk or any of the remaining "
 205                         "ones\n"
 206                    "a - discard this hunk and all later hunks in the file\n"
 207                    "d - do not discard this hunk or any of the later hunks in "
 208                         "the file\n"),
 209 };
 210
 211 static struct patch_mode patch_mode_worktree_nothead = {
 212         .diff_cmd = { "diff-index", "-R", NULL },
 213         .apply_args = { NULL },
 214         .apply_check_args = { NULL },
 215         .prompt_mode = {
 216                 N_("Apply mode change to index and worktree [y,n,q,a,d%s,?]? "),
 217                 N_("Apply deletion to index and worktree [y,n,q,a,d%s,?]? "),
 218                 N_("Apply addition to index and worktree [y,n,q,a,d%s,?]? "),
 219                 N_("Apply this hunk to index and worktree [y,n,q,a,d%s,?]? "),
 220         },
 221         .edit_hunk_hint = N_("If the patch applies cleanly, the edited hunk "
 222                              "will immediately be marked for applying."),
 223         .help_patch_text =
 224                 N_("y - apply this hunk to worktree\n"
 225                    "n - do not apply this hunk to worktree\n"
 226                    "q - quit; do not apply this hunk or any of the remaining "
 227                         "ones\n"
 228                    "a - apply this hunk and all later hunks in the file\n"
 229                    "d - do not apply this hunk or any of the later hunks in "
 230                         "the file\n"),
 231 };
 232
 233 struct hunk_header {
 234         unsigned long old_offset, old_count, new_offset, new_count;
 235         /*
 236          * Start/end offsets to the extra text after the second `@@` in the
 237          * hunk header, e.g. the function signature. This is expected to
 238          * include the newline.
 239          */
 240         size_t extra_start, extra_end, colored_extra_start, colored_extra_end;
 241 };
 242
 243 struct hunk {
 244         size_t start, end, colored_start, colored_end, splittable_into;
 245         ssize_t delta;
 246         enum { UNDECIDED_HUNK = 0, SKIP_HUNK, USE_HUNK } use;
 247         struct hunk_header header;
 248 };
 249
 250 struct add_p_state {
 251         struct add_i_state s;
 252         struct strbuf answer, buf;
 253
 254         /* parsed diff */
 255         struct strbuf plain, colored;
 256         struct file_diff {
 257                 struct hunk head;
 258                 struct hunk *hunk;
 259                 size_t hunk_nr, hunk_alloc;
 260                 unsigned deleted:1, added:1, mode_change:1,binary:1;
 261         } *file_diff;
 262         size_t file_diff_nr;
 263
 264         /* patch mode */
 265         struct patch_mode *mode;
 266         const char *revision;
 267 };
 268
 269 static void err(struct add_p_state *s, const char *fmt, ...)
 270 {
 271         va_list args;
 272
 273         va_start(args, fmt);
 274         fputs(s->s.error_color, stderr);
 275         vfprintf(stderr, fmt, args);
 276         fputs(s->s.reset_color, stderr);
 277         fputc('\n', stderr);
 278         va_end(args);
 279 }
 280
 281 static void setup_child_process(struct add_p_state *s,
 282                                 struct child_process *cp, ...)
 283 {
 284         va_list ap;
 285         const char *arg;
 286
 287         va_start(ap, cp);
 288         while ((arg = va_arg(ap, const char *)))
 289                 strvec_push(&cp->args, arg);
 290         va_end(ap);
 291
 292         cp->git_cmd = 1;
 293         strvec_pushf(&cp->env_array,
 294                      INDEX_ENVIRONMENT "=%s", s->s.r->index_file);
 295 }
 296
 297 static int parse_range(const char **p,
 298                        unsigned long *offset, unsigned long *count)
 299 {
 300         char *pend;
 301
 302         *offset = strtoul(*p, &pend, 10);
 303         if (pend == *p)
 304                 return -1;
 305         if (*pend != ',') {
 306                 *count = 1;
 307                 *p = pend;
 308                 return 0;
 309         }
 310         *count = strtoul(pend + 1, (char **)p, 10);
 311         return *p == pend + 1 ? -1 : 0;
 312 }
 313
 314 static int parse_hunk_header(struct add_p_state *s, struct hunk *hunk)
 315 {
 316         struct hunk_header *header = &hunk->header;
 317         const char *line = s->plain.buf + hunk->start, *p = line;
 318         char *eol = memchr(p, '\n', s->plain.len - hunk->start);
 319
 320         if (!eol)
 321                 eol = s->plain.buf + s->plain.len;
 322
 323         if (!skip_prefix(p, "@@ -", &p) ||
 324             parse_range(&p, &header->old_offset, &header->old_count) < 0 ||
 325             !skip_prefix(p, " +", &p) ||
 326             parse_range(&p, &header->new_offset, &header->new_count) < 0 ||
 327             !skip_prefix(p, " @@", &p))
 328                 return error(_("could not parse hunk header '%.*s'"),
 329                              (int)(eol - line), line);
 330
 331         hunk->start = eol - s->plain.buf + (*eol == '\n');
 332         header->extra_start = p - s->plain.buf;
 333         header->extra_end = hunk->start;
 334
 335         if (!s->colored.len) {
 336                 header->colored_extra_start = header->colored_extra_end = 0;
 337                 return 0;
 338         }
 339
 340         /* Now find the extra text in the colored diff */
 341         line = s->colored.buf + hunk->colored_start;
 342         eol = memchr(line, '\n', s->colored.len - hunk->colored_start);
 343         if (!eol)
 344                 eol = s->colored.buf + s->colored.len;
 345         p = memmem(line, eol - line, "@@ -", 4);
 346         if (!p)
 347                 return error(_("could not parse colored hunk header '%.*s'"),
 348                              (int)(eol - line), line);
 349         p = memmem(p + 4, eol - p - 4, " @@", 3);
 350         if (!p)
 351                 return error(_("could not parse colored hunk header '%.*s'"),
 352                              (int)(eol - line), line);
 353         hunk->colored_start = eol - s->colored.buf + (*eol == '\n');
 354         header->colored_extra_start = p + 3 - s->colored.buf;
 355         header->colored_extra_end = hunk->colored_start;
 356
 357         return 0;
 358 }
 359
 360 static int is_octal(const char *p, size_t len)
 361 {
 362         if (!len)
 363                 return 0;
 364
 365         while (len--)
 366                 if (*p < '0' || *(p++) > '7')
 367                         return 0;
 368         return 1;
 369 }
 370
 371 static int parse_diff(struct add_p_state *s, const struct pathspec *ps)
 372 {
 373         struct strvec args = STRVEC_INIT;
 374         const char *diff_algorithm = s->s.interactive_diff_algorithm;
 375         struct strbuf *plain = &s->plain, *colored = NULL;
 376         struct child_process cp = CHILD_PROCESS_INIT;
 377         char *p, *pend, *colored_p = NULL, *colored_pend = NULL, marker = '\0';
 378         size_t file_diff_alloc = 0, i, color_arg_index;
 379         struct file_diff *file_diff = NULL;
 380         struct hunk *hunk = NULL;
 381         int res;
 382
 383         strvec_pushv(&args, s->mode->diff_cmd);
 384         if (diff_algorithm)
 385                 strvec_pushf(&args, "--diff-algorithm=%s", diff_algorithm);
 386         if (s->revision) {
 387                 struct object_id oid;
 388                 strvec_push(&args,
 389                             /* could be on an unborn branch */
 390                             !strcmp("HEAD", s->revision) &&
 391                             get_oid("HEAD", &oid) ?
 392                             empty_tree_oid_hex() : s->revision);
 393         }
 394         color_arg_index = args.nr;
 395         /* Use `--no-color` explicitly, just in case `diff.color = always`. */
 396         strvec_pushl(&args, "--no-color", "-p", "--", NULL);
 397         for (i = 0; i < ps->nr; i++)
 398                 strvec_push(&args, ps->items[i].original);
 399
 400         setup_child_process(s, &cp, NULL);
 401         cp.argv = args.v;
 402         res = capture_command(&cp, plain, 0);
 403         if (res) {
 404                 strvec_clear(&args);
 405                 return error(_("could not parse diff"));
 406         }
 407         if (!plain->len) {
 408                 strvec_clear(&args);
 409                 return 0;
 410         }
 411         strbuf_complete_line(plain);
 412
 413         if (want_color_fd(1, -1)) {
 414                 struct child_process colored_cp = CHILD_PROCESS_INIT;
 415                 const char *diff_filter = s->s.interactive_diff_filter;
 416
 417                 setup_child_process(s, &colored_cp, NULL);
 418                 xsnprintf((char *)args.v[color_arg_index], 8, "--color");
 419                 colored_cp.argv = args.v;
 420                 colored = &s->colored;
 421                 res = capture_command(&colored_cp, colored, 0);
 422                 strvec_clear(&args);
 423                 if (res)
 424                         return error(_("could not parse colored diff"));
 425
 426                 if (diff_filter) {
 427                         struct child_process filter_cp = CHILD_PROCESS_INIT;
 428
 429                         setup_child_process(s, &filter_cp,
 430                                             diff_filter, NULL);
 431                         filter_cp.git_cmd = 0;
 432                         filter_cp.use_shell = 1;
 433                         strbuf_reset(&s->buf);
 434                         if (pipe_command(&filter_cp,
 435                                          colored->buf, colored->len,
 436                                          &s->buf, colored->len,
 437                                          NULL, 0) < 0)
 438                                 return error(_("failed to run '%s'"),
 439                                              diff_filter);
 440                         strbuf_swap(colored, &s->buf);
 441                 }
 442
 443                 strbuf_complete_line(colored);
 444                 colored_p = colored->buf;
 445                 colored_pend = colored_p + colored->len;
 446         }
 447         strvec_clear(&args);
 448
 449         /* parse files and hunks */
 450         p = plain->buf;
 451         pend = p + plain->len;
 452         while (p != pend) {
 453                 char *eol = memchr(p, '\n', pend - p);
 454                 const char *deleted = NULL, *added = NULL, *mode_change = NULL;
 455
 456                 if (!eol)
 457                         eol = pend;
 458
 459                 if (starts_with(p, "diff ")) {
 460                         ALLOC_GROW_BY(s->file_diff, s->file_diff_nr, 1,
 461                                    file_diff_alloc);
 462                         file_diff = s->file_diff + s->file_diff_nr - 1;
 463                         hunk = &file_diff->head;
 464                         hunk->start = p - plain->buf;
 465                         if (colored_p)
 466                                 hunk->colored_start = colored_p - colored->buf;
 467                         marker = '\0';
 468                 } else if (p == plain->buf)
 469                         BUG("diff starts with unexpected line:\n"
 470                             "%.*s\n", (int)(eol - p), p);
 471                 else if (file_diff->deleted || file_diff->added)
 472                         ; /* keep the rest of the file in a single "hunk" */
 473                 else if (starts_with(p, "@@ ") ||
 474                          (hunk == &file_diff->head &&
 475                           (skip_prefix(p, "deleted file", &deleted) ||
 476                            skip_prefix(p, "new file", &added)))) {
 477                         if (marker == '-' || marker == '+')
 478                                 /*
 479                                  * Should not happen; previous hunk did not end
 480                                  * in a context line? Handle it anyway.
 481                                  */
 482                                 hunk->splittable_into++;
 483
 484                         ALLOC_GROW_BY(file_diff->hunk, file_diff->hunk_nr, 1,
 485                                    file_diff->hunk_alloc);
 486                         hunk = file_diff->hunk + file_diff->hunk_nr - 1;
 487
 488                         hunk->start = p - plain->buf;
 489                         if (colored)
 490                                 hunk->colored_start = colored_p - colored->buf;
 491
 492                         if (deleted)
 493                                 file_diff->deleted = 1;
 494                         else if (added)
 495                                 file_diff->added = 1;
 496                         else if (parse_hunk_header(s, hunk) < 0)
 497                                 return -1;
 498
 499                         /*
 500                          * Start counting into how many hunks this one can be
 501                          * split
 502                          */
 503                         marker = *p;
 504                 } else if (hunk == &file_diff->head &&
 505                            skip_prefix(p, "old mode ", &mode_change) &&
 506                            is_octal(mode_change, eol - mode_change)) {
 507                         if (file_diff->mode_change)
 508                                 BUG("double mode change?\n\n%.*s",
 509                                     (int)(eol - plain->buf), plain->buf);
 510                         if (file_diff->hunk_nr)
 511                                 BUG("mode change in the middle?\n\n%.*s",
 512                                     (int)(eol - plain->buf), plain->buf);
 513
 514                         /*
 515                          * Do *not* change `hunk`: the mode change pseudo-hunk
 516                          * is _part of_ the header "hunk".
 517                          */
 518                         file_diff->mode_change = 1;
 519                         ALLOC_GROW_BY(file_diff->hunk, file_diff->hunk_nr, 1,
 520                                    file_diff->hunk_alloc);
 521                         file_diff->hunk->start = p - plain->buf;
 522                         if (colored_p)
 523                                 file_diff->hunk->colored_start =
 524                                         colored_p - colored->buf;
 525                 } else if (hunk == &file_diff->head &&
 526                            skip_prefix(p, "new mode ", &mode_change) &&
 527                            is_octal(mode_change, eol - mode_change)) {
 528
 529                         /*
 530                          * Extend the "mode change" pseudo-hunk to include also
 531                          * the "new mode" line.
 532                          */
 533                         if (!file_diff->mode_change)
 534                                 BUG("'new mode' without 'old mode'?\n\n%.*s",
 535                                     (int)(eol - plain->buf), plain->buf);
 536                         if (file_diff->hunk_nr != 1)
 537                                 BUG("mode change in the middle?\n\n%.*s",
 538                                     (int)(eol - plain->buf), plain->buf);
 539                         if (p - plain->buf != file_diff->hunk->end)
 540                                 BUG("'new mode' does not immediately follow "
 541                                     "'old mode'?\n\n%.*s",
 542                                     (int)(eol - plain->buf), plain->buf);
 543                 } else if (hunk == &file_diff->head &&
 544                            starts_with(p, "Binary files "))
 545                         file_diff->binary = 1;
 546
 547                 if (!!file_diff->deleted + !!file_diff->added +
 548                     !!file_diff->mode_change > 1)
 549                         BUG("diff can only contain delete *or* add *or* a "
 550                             "mode change?!?\n%.*s",
 551                             (int)(eol - (plain->buf + file_diff->head.start)),
 552                             plain->buf + file_diff->head.start);
 553
 554                 if ((marker == '-' || marker == '+') && *p == ' ')
 555                         hunk->splittable_into++;
 556                 if (marker && *p != '\\')
 557                         marker = *p;
 558
 559                 p = eol == pend ? pend : eol + 1;
 560                 hunk->end = p - plain->buf;
 561
 562                 if (colored) {
 563                         char *colored_eol = memchr(colored_p, '\n',
 564                                                    colored_pend - colored_p);
 565                         if (colored_eol)
 566                                 colored_p = colored_eol + 1;
 567                         else if (p != pend)
 568                                 /* colored shorter than non-colored? */
 569                                 goto mismatched_output;
 570                         else
 571                                 colored_p = colored_pend;
 572
 573                         hunk->colored_end = colored_p - colored->buf;
 574                 }
 575
 576                 if (mode_change) {
 577                         if (file_diff->hunk_nr != 1)
 578                                 BUG("mode change in hunk #%d???",
 579                                     (int)file_diff->hunk_nr);
 580                         /* Adjust the end of the "mode change" pseudo-hunk */
 581                         file_diff->hunk->end = hunk->end;
 582                         if (colored)
 583                                 file_diff->hunk->colored_end = hunk->colored_end;
 584                 }
 585         }
 586
 587         if (marker == '-' || marker == '+')
 588                 /*
 589                  * Last hunk ended in non-context line (i.e. it appended lines
 590                  * to the file, so there are no trailing context lines).
 591                  */
 592                 hunk->splittable_into++;
 593
 594         /* non-colored shorter than colored? */
 595         if (colored_p != colored_pend) {
 596 mismatched_output:
 597                 error(_("mismatched output from interactive.diffFilter"));
 598                 advise(_("Your filter must maintain a one-to-one correspondence\n"
 599                          "between its input and output lines."));
 600                 return -1;
 601         }
 602
 603         return 0;
 604 }
 605
 606 static size_t find_next_line(struct strbuf *sb, size_t offset)
 607 {
 608         char *eol;
 609
 610         if (offset >= sb->len)
 611                 BUG("looking for next line beyond buffer (%d >= %d)\n%s",
 612                     (int)offset, (int)sb->len, sb->buf);
 613
 614         eol = memchr(sb->buf + offset, '\n', sb->len - offset);
 615         if (!eol)
 616                 return sb->len;
 617         return eol - sb->buf + 1;
 618 }
 619
 620 static void render_hunk(struct add_p_state *s, struct hunk *hunk,
 621                         ssize_t delta, int colored, struct strbuf *out)
 622 {
 623         struct hunk_header *header = &hunk->header;
 624
 625         if (hunk->header.old_offset != 0 || hunk->header.new_offset != 0) {
 626                 /*
 627                  * Generate the hunk header dynamically, except for special
 628                  * hunks (such as the diff header).
 629                  */
 630                 const char *p;
 631                 size_t len;
 632                 unsigned long old_offset = header->old_offset;
 633                 unsigned long new_offset = header->new_offset;
 634
 635                 if (!colored) {
 636                         p = s->plain.buf + header->extra_start;
 637                         len = header->extra_end - header->extra_start;
 638                 } else {
 639                         strbuf_addstr(out, s->s.fraginfo_color);
 640                         p = s->colored.buf + header->colored_extra_start;
 641                         len = header->colored_extra_end
 642                                 - header->colored_extra_start;
 643                 }
 644
 645                 if (s->mode->is_reverse)
 646                         old_offset -= delta;
 647                 else
 648                         new_offset += delta;
 649
 650                 strbuf_addf(out, "@@ -%lu,%lu +%lu,%lu @@",
 651                             old_offset, header->old_count,
 652                             new_offset, header->new_count);
 653                 if (len)
 654                         strbuf_add(out, p, len);
 655                 else if (colored)
 656                         strbuf_addf(out, "%s\n", GIT_COLOR_RESET);
 657                 else
 658                         strbuf_addch(out, '\n');
 659         }
 660
 661         if (colored)
 662                 strbuf_add(out, s->colored.buf + hunk->colored_start,
 663                            hunk->colored_end - hunk->colored_start);
 664         else
 665                 strbuf_add(out, s->plain.buf + hunk->start,
 666                            hunk->end - hunk->start);
 667 }
 668
 669 static void render_diff_header(struct add_p_state *s,
 670                                struct file_diff *file_diff, int colored,
 671                                struct strbuf *out)
 672 {
 673         /*
 674          * If there was a mode change, the first hunk is a pseudo hunk that
 675          * corresponds to the mode line in the header. If the user did not want
 676          * to stage that "hunk", we actually have to cut it out from the header.
 677          */
 678         int skip_mode_change =
 679                 file_diff->mode_change && file_diff->hunk->use != USE_HUNK;
 680         struct hunk *head = &file_diff->head, *first = file_diff->hunk;
 681
 682         if (!skip_mode_change) {
 683                 render_hunk(s, head, 0, colored, out);
 684                 return;
 685         }
 686
 687         if (colored) {
 688                 const char *p = s->colored.buf;
 689
 690                 strbuf_add(out, p + head->colored_start,
 691                             first->colored_start - head->colored_start);
 692                 strbuf_add(out, p + first->colored_end,
 693                             head->colored_end - first->colored_end);
 694         } else {
 695                 const char *p = s->plain.buf;
 696
 697                 strbuf_add(out, p + head->start, first->start - head->start);
 698                 strbuf_add(out, p + first->end, head->end - first->end);
 699         }
 700 }
 701
 702 /* Coalesce hunks again that were split */
 703 static int merge_hunks(struct add_p_state *s, struct file_diff *file_diff,
 704                        size_t *hunk_index, int use_all, struct hunk *merged)
 705 {
 706         size_t i = *hunk_index, delta;
 707         struct hunk *hunk = file_diff->hunk + i;
 708         /* `header` corresponds to the merged hunk */
 709         struct hunk_header *header = &merged->header, *next;
 710
 711         if (!use_all && hunk->use != USE_HUNK)
 712                 return 0;
 713
 714         *merged = *hunk;
 715         /* We simply skip the colored part (if any) when merging hunks */
 716         merged->colored_start = merged->colored_end = 0;
 717
 718         for (; i + 1 < file_diff->hunk_nr; i++) {
 719                 hunk++;
 720                 next = &hunk->header;
 721
 722                 /*
 723                  * Stop merging hunks when:
 724                  *
 725                  * - the hunk is not selected for use, or
 726                  * - the hunk does not overlap with the already-merged hunk(s)
 727                  */
 728                 if ((!use_all && hunk->use != USE_HUNK) ||
 729                     header->new_offset >= next->new_offset + merged->delta ||
 730                     header->new_offset + header->new_count
 731                     < next->new_offset + merged->delta)
 732                         break;
 733
 734                 /*
 735                  * If the hunks were not edited, and overlap, we can simply
 736                  * extend the line range.
 737                  */
 738                 if (merged->start < hunk->start && merged->end > hunk->start) {
 739                         merged->end = hunk->end;
 740                         merged->colored_end = hunk->colored_end;
 741                         delta = 0;
 742                 } else {
 743                         const char *plain = s->plain.buf;
 744                         size_t  overlapping_line_count = header->new_offset
 745                                 + header->new_count - merged->delta
 746                                 - next->new_offset;
 747                         size_t overlap_end = hunk->start;
 748                         size_t overlap_start = overlap_end;
 749                         size_t overlap_next, len, j;
 750
 751                         /*
 752                          * One of the hunks was edited: the modified hunk was
 753                          * appended to the strbuf `s->plain`.
 754                          *
 755                          * Let's ensure that at least the last context line of
 756                          * the first hunk overlaps with the corresponding line
 757                          * of the second hunk, and then merge.
 758                          */
 759                         for (j = 0; j < overlapping_line_count; j++) {
 760                                 overlap_next = find_next_line(&s->plain,
 761                                                               overlap_end);
 762
 763                                 if (overlap_next > hunk->end)
 764                                         BUG("failed to find %d context lines "
 765                                             "in:\n%.*s",
 766                                             (int)overlapping_line_count,
 767                                             (int)(hunk->end - hunk->start),
 768                                             plain + hunk->start);
 769
 770                                 if (plain[overlap_end] != ' ')
 771                                         return error(_("expected context line "
 772                                                        "#%d in\n%.*s"),
 773                                                      (int)(j + 1),
 774                                                      (int)(hunk->end
 775                                                            - hunk->start),
 776                                                      plain + hunk->start);
 777
 778                                 overlap_start = overlap_end;
 779                                 overlap_end = overlap_next;
 780                         }
 781                         len = overlap_end - overlap_start;
 782
 783                         if (len > merged->end - merged->start ||
 784                             memcmp(plain + merged->end - len,
 785                                    plain + overlap_start, len))
 786                                 return error(_("hunks do not overlap:\n%.*s\n"
 787                                                "\tdoes not end with:\n%.*s"),
 788                                              (int)(merged->end - merged->start),
 789                                              plain + merged->start,
 790                                              (int)len, plain + overlap_start);
 791
 792                         /*
 793                          * Since the start-end ranges are not adjacent, we
 794                          * cannot simply take the union of the ranges. To
 795                          * address that, we temporarily append the union of the
 796                          * lines to the `plain` strbuf.
 797                          */
 798                         if (merged->end != s->plain.len) {
 799                                 size_t start = s->plain.len;
 800
 801                                 strbuf_add(&s->plain, plain + merged->start,
 802                                            merged->end - merged->start);
 803                                 plain = s->plain.buf;
 804                                 merged->start = start;
 805                                 merged->end = s->plain.len;
 806                         }
 807
 808                         strbuf_add(&s->plain,
 809                                    plain + overlap_end,
 810                                    hunk->end - overlap_end);
 811                         merged->end = s->plain.len;
 812                         merged->splittable_into += hunk->splittable_into;
 813                         delta = merged->delta;
 814                         merged->delta += hunk->delta;
 815                 }
 816
 817                 header->old_count = next->old_offset + next->old_count
 818                         - header->old_offset;
 819                 header->new_count = next->new_offset + delta
 820                         + next->new_count - header->new_offset;
 821         }
 822
 823         if (i == *hunk_index)
 824                 return 0;
 825
 826         *hunk_index = i;
 827         return 1;
 828 }
 829
 830 static void reassemble_patch(struct add_p_state *s,
 831                              struct file_diff *file_diff, int use_all,
 832                              struct strbuf *out)
 833 {
 834         struct hunk *hunk;
 835         size_t save_len = s->plain.len, i;
 836         ssize_t delta = 0;
 837
 838         render_diff_header(s, file_diff, 0, out);
 839
 840         for (i = file_diff->mode_change; i < file_diff->hunk_nr; i++) {
 841                 struct hunk merged = { 0 };
 842
 843                 hunk = file_diff->hunk + i;
 844                 if (!use_all && hunk->use != USE_HUNK)
 845                         delta += hunk->header.old_count
 846                                 - hunk->header.new_count;
 847                 else {
 848                         /* merge overlapping hunks into a temporary hunk */
 849                         if (merge_hunks(s, file_diff, &i, use_all, &merged))
 850                                 hunk = &merged;
 851
 852                         render_hunk(s, hunk, delta, 0, out);
 853
 854                         /*
 855                          * In case `merge_hunks()` used `plain` as a scratch
 856                          * pad (this happens when an edited hunk had to be
 857                          * coalesced with another hunk).
 858                          */
 859                         strbuf_setlen(&s->plain, save_len);
 860
 861                         delta += hunk->delta;
 862                 }
 863         }
 864 }
 865
 866 static int split_hunk(struct add_p_state *s, struct file_diff *file_diff,
 867                        size_t hunk_index)
 868 {
 869         int colored = !!s->colored.len, first = 1;
 870         struct hunk *hunk = file_diff->hunk + hunk_index;
 871         size_t splittable_into;
 872         size_t end, colored_end, current, colored_current = 0, context_line_count;
 873         struct hunk_header remaining, *header;
 874         char marker, ch;
 875
 876         if (hunk_index >= file_diff->hunk_nr)
 877                 BUG("invalid hunk index: %d (must be >= 0 and < %d)",
 878                     (int)hunk_index, (int)file_diff->hunk_nr);
 879
 880         if (hunk->splittable_into < 2)
 881                 return 0;
 882         splittable_into = hunk->splittable_into;
 883
 884         end = hunk->end;
 885         colored_end = hunk->colored_end;
 886
 887         remaining = hunk->header;
 888
 889         file_diff->hunk_nr += splittable_into - 1;
 890         ALLOC_GROW(file_diff->hunk, file_diff->hunk_nr, file_diff->hunk_alloc);
 891         if (hunk_index + splittable_into < file_diff->hunk_nr)
 892                 memmove(file_diff->hunk + hunk_index + splittable_into,
 893                         file_diff->hunk + hunk_index + 1,
 894                         (file_diff->hunk_nr - hunk_index - splittable_into)
 895                         * sizeof(*hunk));
 896         hunk = file_diff->hunk + hunk_index;
 897         hunk->splittable_into = 1;
 898         memset(hunk + 1, 0, (splittable_into - 1) * sizeof(*hunk));
 899
 900         header = &hunk->header;
 901         header->old_count = header->new_count = 0;
 902
 903         current = hunk->start;
 904         if (colored)
 905                 colored_current = hunk->colored_start;
 906         marker = '\0';
 907         context_line_count = 0;
 908
 909         while (splittable_into > 1) {
 910                 ch = s->plain.buf[current];
 911
 912                 if (!ch)
 913                         BUG("buffer overrun while splitting hunks");
 914
 915                 /*
 916                  * Is this the first context line after a chain of +/- lines?
 917                  * Then record the start of the next split hunk.
 918                  */
 919                 if ((marker == '-' || marker == '+') && ch == ' ') {
 920                         first = 0;
 921                         hunk[1].start = current;
 922                         if (colored)
 923                                 hunk[1].colored_start = colored_current;
 924                         context_line_count = 0;
 925                 }
 926
 927                 /*
 928                  * Was the previous line a +/- one? Alternatively, is this the
 929                  * first line (and not a +/- one)?
 930                  *
 931                  * Then just increment the appropriate counter and continue
 932                  * with the next line.
 933                  */
 934                 if (marker != ' ' || (ch != '-' && ch != '+')) {
 935 next_hunk_line:
 936                         /* Comment lines are attached to the previous line */
 937                         if (ch == '\\')
 938                                 ch = marker ? marker : ' ';
 939
 940                         /* current hunk not done yet */
 941                         if (ch == ' ')
 942                                 context_line_count++;
 943                         else if (ch == '-')
 944                                 header->old_count++;
 945                         else if (ch == '+')
 946                                 header->new_count++;
 947                         else
 948                                 BUG("unhandled diff marker: '%c'", ch);
 949                         marker = ch;
 950                         current = find_next_line(&s->plain, current);
 951                         if (colored)
 952                                 colored_current =
 953                                         find_next_line(&s->colored,
 954                                                        colored_current);
 955                         continue;
 956                 }
 957
 958                 /*
 959                  * We got us the start of a new hunk!
 960                  *
 961                  * This is a context line, so it is shared with the previous
 962                  * hunk, if any.
 963                  */
 964
 965                 if (first) {
 966                         if (header->old_count || header->new_count)
 967                                 BUG("counts are off: %d/%d",
 968                                     (int)header->old_count,
 969                                     (int)header->new_count);
 970
 971                         header->old_count = context_line_count;
 972                         header->new_count = context_line_count;
 973                         context_line_count = 0;
 974                         first = 0;
 975                         goto next_hunk_line;
 976                 }
 977
 978                 remaining.old_offset += header->old_count;
 979                 remaining.old_count -= header->old_count;
 980                 remaining.new_offset += header->new_count;
 981                 remaining.new_count -= header->new_count;
 982
 983                 /* initialize next hunk header's offsets */
 984                 hunk[1].header.old_offset =
 985                         header->old_offset + header->old_count;
 986                 hunk[1].header.new_offset =
 987                         header->new_offset + header->new_count;
 988
 989                 /* add one split hunk */
 990                 header->old_count += context_line_count;
 991                 header->new_count += context_line_count;
 992
 993                 hunk->end = current;
 994                 if (colored)
 995                         hunk->colored_end = colored_current;
 996
 997                 hunk++;
 998                 hunk->splittable_into = 1;
 999                 hunk->use = hunk[-1].use;
1000                 header = &hunk->header;
1001
1002                 header->old_count = header->new_count = context_line_count;
1003                 context_line_count = 0;
1004
1005                 splittable_into--;
1006                 marker = ch;
1007         }
1008
1009         /* last hunk simply gets the rest */
1010         if (header->old_offset != remaining.old_offset)
1011                 BUG("miscounted old_offset: %lu != %lu",
1012                     header->old_offset, remaining.old_offset);
1013         if (header->new_offset != remaining.new_offset)
1014                 BUG("miscounted new_offset: %lu != %lu",
1015                     header->new_offset, remaining.new_offset);
1016         header->old_count = remaining.old_count;
1017         header->new_count = remaining.new_count;
1018         hunk->end = end;
1019         if (colored)
1020                 hunk->colored_end = colored_end;
1021
1022         return 0;
1023 }
1024
1025 static void recolor_hunk(struct add_p_state *s, struct hunk *hunk)
1026 {
1027         const char *plain = s->plain.buf;
1028         size_t current, eol, next;
1029
1030         if (!s->colored.len)
1031                 return;
1032
1033         hunk->colored_start = s->colored.len;
1034         for (current = hunk->start; current < hunk->end; ) {
1035                 for (eol = current; eol < hunk->end; eol++)
1036                         if (plain[eol] == '\n')
1037                                 break;
1038                 next = eol + (eol < hunk->end);
1039                 if (eol > current && plain[eol - 1] == '\r')
1040                         eol--;
1041
1042                 strbuf_addstr(&s->colored,
1043                               plain[current] == '-' ?
1044                               s->s.file_old_color :
1045                               plain[current] == '+' ?
1046                               s->s.file_new_color :
1047                               s->s.context_color);
1048                 strbuf_add(&s->colored, plain + current, eol - current);
1049                 strbuf_addstr(&s->colored, GIT_COLOR_RESET);
1050                 if (next > eol)
1051                         strbuf_add(&s->colored, plain + eol, next - eol);
1052                 current = next;
1053         }
1054         hunk->colored_end = s->colored.len;
1055 }
1056
1057 static int edit_hunk_manually(struct add_p_state *s, struct hunk *hunk)
1058 {
1059         size_t i;
1060
1061         strbuf_reset(&s->buf);
1062         strbuf_commented_addf(&s->buf, _("Manual hunk edit mode -- see bottom for "
1063                                       "a quick guide.\n"));
1064         render_hunk(s, hunk, 0, 0, &s->buf);
1065         strbuf_commented_addf(&s->buf,
1066                               _("---\n"
1067                                 "To remove '%c' lines, make them ' ' lines "
1068                                 "(context).\n"
1069                                 "To remove '%c' lines, delete them.\n"
1070                                 "Lines starting with %c will be removed.\n"),
1071                               s->mode->is_reverse ? '+' : '-',
1072                               s->mode->is_reverse ? '-' : '+',
1073                               comment_line_char);
1074         strbuf_commented_addf(&s->buf, "%s", _(s->mode->edit_hunk_hint));
1075         /*
1076          * TRANSLATORS: 'it' refers to the patch mentioned in the previous
1077          * messages.
1078          */
1079         strbuf_commented_addf(&s->buf,
1080                               _("If it does not apply cleanly, you will be "
1081                                 "given an opportunity to\n"
1082                                 "edit again.  If all lines of the hunk are "
1083                                 "removed, then the edit is\n"
1084                                 "aborted and the hunk is left unchanged.\n"));
1085
1086         if (strbuf_edit_interactively(&s->buf, "addp-hunk-edit.diff", NULL) < 0)
1087                 return -1;
1088
1089         /* strip out commented lines */
1090         hunk->start = s->plain.len;
1091         for (i = 0; i < s->buf.len; ) {
1092                 size_t next = find_next_line(&s->buf, i);
1093
1094                 if (s->buf.buf[i] != comment_line_char)
1095                         strbuf_add(&s->plain, s->buf.buf + i, next - i);
1096                 i = next;
1097         }
1098
1099         hunk->end = s->plain.len;
1100         if (hunk->end == hunk->start)
1101                 /* The user aborted editing by deleting everything */
1102                 return 0;
1103
1104         recolor_hunk(s, hunk);
1105
1106         /*
1107          * If the hunk header is intact, parse it, otherwise simply use the
1108          * hunk header prior to editing (which will adjust `hunk->start` to
1109          * skip the hunk header).
1110          */
1111         if (s->plain.buf[hunk->start] == '@' &&
1112             parse_hunk_header(s, hunk) < 0)
1113                 return error(_("could not parse hunk header"));
1114
1115         return 1;
1116 }
1117
1118 static ssize_t recount_edited_hunk(struct add_p_state *s, struct hunk *hunk,
1119                                    size_t orig_old_count, size_t orig_new_count)
1120 {
1121         struct hunk_header *header = &hunk->header;
1122         size_t i;
1123
1124         header->old_count = header->new_count = 0;
1125         for (i = hunk->start; i < hunk->end; ) {
1126                 switch (s->plain.buf[i]) {
1127                 case '-':
1128                         header->old_count++;
1129                         break;
1130                 case '+':
1131                         header->new_count++;
1132                         break;
1133                 case ' ': case '\r': case '\n':
1134                         header->old_count++;
1135                         header->new_count++;
1136                         break;
1137                 }
1138
1139                 i = find_next_line(&s->plain, i);
1140         }
1141
1142         return orig_old_count - orig_new_count
1143                 - header->old_count + header->new_count;
1144 }
1145
1146 static int run_apply_check(struct add_p_state *s,
1147                            struct file_diff *file_diff)
1148 {
1149         struct child_process cp = CHILD_PROCESS_INIT;
1150
1151         strbuf_reset(&s->buf);
1152         reassemble_patch(s, file_diff, 1, &s->buf);
1153
1154         setup_child_process(s, &cp,
1155                             "apply", "--check", NULL);
1156         strvec_pushv(&cp.args, s->mode->apply_check_args);
1157         if (pipe_command(&cp, s->buf.buf, s->buf.len, NULL, 0, NULL, 0))
1158                 return error(_("'git apply --cached' failed"));
1159
1160         return 0;
1161 }
1162
1163 static int read_single_character(struct add_p_state *s)
1164 {
1165         if (s->s.use_single_key) {
1166                 int res = read_key_without_echo(&s->answer);
1167                 printf("%s\n", res == EOF ? "" : s->answer.buf);
1168                 return res;
1169         }
1170
1171         if (git_read_line_interactively(&s->answer) == EOF)
1172                 return EOF;
1173         return 0;
1174 }
1175
1176 static int prompt_yesno(struct add_p_state *s, const char *prompt)
1177 {
1178         for (;;) {
1179                 color_fprintf(stdout, s->s.prompt_color, "%s", _(prompt));
1180                 fflush(stdout);
1181                 if (read_single_character(s) == EOF)
1182                         return -1;
1183                 switch (tolower(s->answer.buf[0])) {
1184                 case 'n': return 0;
1185                 case 'y': return 1;
1186                 }
1187         }
1188 }
1189
1190 static int edit_hunk_loop(struct add_p_state *s,
1191                           struct file_diff *file_diff, struct hunk *hunk)
1192 {
1193         size_t plain_len = s->plain.len, colored_len = s->colored.len;
1194         struct hunk backup;
1195
1196         backup = *hunk;
1197
1198         for (;;) {
1199                 int res = edit_hunk_manually(s, hunk);
1200                 if (res == 0) {
1201                         /* abandoned */
1202                         *hunk = backup;
1203                         return -1;
1204                 }
1205
1206                 if (res > 0) {
1207                         hunk->delta +=
1208                                 recount_edited_hunk(s, hunk,
1209                                                     backup.header.old_count,
1210                                                     backup.header.new_count);
1211                         if (!run_apply_check(s, file_diff))
1212                                 return 0;
1213                 }
1214
1215                 /* Drop edits (they were appended to s->plain) */
1216                 strbuf_setlen(&s->plain, plain_len);
1217                 strbuf_setlen(&s->colored, colored_len);
1218                 *hunk = backup;
1219
1220                 /*
1221                  * TRANSLATORS: do not translate [y/n]
1222                  * The program will only accept that input at this point.
1223                  * Consider translating (saying "no" discards!) as
1224                  * (saying "n" for "no" discards!) if the translation
1225                  * of the word "no" does not start with n.
1226                  */
1227                 res = prompt_yesno(s, _("Your edited hunk does not apply. "
1228                                         "Edit again (saying \"no\" discards!) "
1229                                         "[y/n]? "));
1230                 if (res < 1)
1231                         return -1;
1232         }
1233 }
1234
1235 static int apply_for_checkout(struct add_p_state *s, struct strbuf *diff,
1236                               int is_reverse)
1237 {
1238         const char *reverse = is_reverse ? "-R" : NULL;
1239         struct child_process check_index = CHILD_PROCESS_INIT;
1240         struct child_process check_worktree = CHILD_PROCESS_INIT;
1241         struct child_process apply_index = CHILD_PROCESS_INIT;
1242         struct child_process apply_worktree = CHILD_PROCESS_INIT;
1243         int applies_index, applies_worktree;
1244
1245         setup_child_process(s, &check_index,
1246                             "apply", "--cached", "--check", reverse, NULL);
1247         applies_index = !pipe_command(&check_index, diff->buf, diff->len,
1248                                       NULL, 0, NULL, 0);
1249
1250         setup_child_process(s, &check_worktree,
1251                             "apply", "--check", reverse, NULL);
1252         applies_worktree = !pipe_command(&check_worktree, diff->buf, diff->len,
1253                                          NULL, 0, NULL, 0);
1254
1255         if (applies_worktree && applies_index) {
1256                 setup_child_process(s, &apply_index,
1257                                     "apply", "--cached", reverse, NULL);
1258                 pipe_command(&apply_index, diff->buf, diff->len,
1259                              NULL, 0, NULL, 0);
1260
1261                 setup_child_process(s, &apply_worktree,
1262                                     "apply", reverse, NULL);
1263                 pipe_command(&apply_worktree, diff->buf, diff->len,
1264                              NULL, 0, NULL, 0);
1265
1266                 return 1;
1267         }
1268
1269         if (!applies_index) {
1270                 err(s, _("The selected hunks do not apply to the index!"));
1271                 if (prompt_yesno(s, _("Apply them to the worktree "
1272                                           "anyway? ")) > 0) {
1273                         setup_child_process(s, &apply_worktree,
1274                                             "apply", reverse, NULL);
1275                         return pipe_command(&apply_worktree, diff->buf,
1276                                             diff->len, NULL, 0, NULL, 0);
1277                 }
1278                 err(s, _("Nothing was applied.\n"));
1279         } else
1280                 /* As a last resort, show the diff to the user */
1281                 fwrite(diff->buf, diff->len, 1, stderr);
1282
1283         return 0;
1284 }
1285
1286 #define SUMMARY_HEADER_WIDTH 20
1287 #define SUMMARY_LINE_WIDTH 80
1288 static void summarize_hunk(struct add_p_state *s, struct hunk *hunk,
1289                            struct strbuf *out)
1290 {
1291         struct hunk_header *header = &hunk->header;
1292         struct strbuf *plain = &s->plain;
1293         size_t len = out->len, i;
1294
1295         strbuf_addf(out, " -%lu,%lu +%lu,%lu ",
1296                     header->old_offset, header->old_count,
1297                     header->new_offset, header->new_count);
1298         if (out->len - len < SUMMARY_HEADER_WIDTH)
1299                 strbuf_addchars(out, ' ',
1300                                 SUMMARY_HEADER_WIDTH + len - out->len);
1301         for (i = hunk->start; i < hunk->end; i = find_next_line(plain, i))
1302                 if (plain->buf[i] != ' ')
1303                         break;
1304         if (i < hunk->end)
1305                 strbuf_add(out, plain->buf + i, find_next_line(plain, i) - i);
1306         if (out->len - len > SUMMARY_LINE_WIDTH)
1307                 strbuf_setlen(out, len + SUMMARY_LINE_WIDTH);
1308         strbuf_complete_line(out);
1309 }
1310
1311 #define DISPLAY_HUNKS_LINES 20
1312 static size_t display_hunks(struct add_p_state *s,
1313                             struct file_diff *file_diff, size_t start_index)
1314 {
1315         size_t end_index = start_index + DISPLAY_HUNKS_LINES;
1316
1317         if (end_index > file_diff->hunk_nr)
1318                 end_index = file_diff->hunk_nr;
1319
1320         while (start_index < end_index) {
1321                 struct hunk *hunk = file_diff->hunk + start_index++;
1322
1323                 strbuf_reset(&s->buf);
1324                 strbuf_addf(&s->buf, "%c%2d: ", hunk->use == USE_HUNK ? '+'
1325                             : hunk->use == SKIP_HUNK ? '-' : ' ',
1326                             (int)start_index);
1327                 summarize_hunk(s, hunk, &s->buf);
1328                 fputs(s->buf.buf, stdout);
1329         }
1330
1331         return end_index;
1332 }
1333
1334 static const char help_patch_remainder[] =
1335 N_("j - leave this hunk undecided, see next undecided hunk\n"
1336    "J - leave this hunk undecided, see next hunk\n"
1337    "k - leave this hunk undecided, see previous undecided hunk\n"
1338    "K - leave this hunk undecided, see previous hunk\n"
1339    "g - select a hunk to go to\n"
1340    "/ - search for a hunk matching the given regex\n"
1341    "s - split the current hunk into smaller hunks\n"
1342    "e - manually edit the current hunk\n"
1343    "? - print help\n");
1344
1345 static int patch_update_file(struct add_p_state *s,
1346                              struct file_diff *file_diff)
1347 {
1348         size_t hunk_index = 0;
1349         ssize_t i, undecided_previous, undecided_next;
1350         struct hunk *hunk;
1351         char ch;
1352         struct child_process cp = CHILD_PROCESS_INIT;
1353         int colored = !!s->colored.len, quit = 0;
1354         enum prompt_mode_type prompt_mode_type;
1355         enum {
1356                 ALLOW_GOTO_PREVIOUS_HUNK = 1 << 0,
1357                 ALLOW_GOTO_PREVIOUS_UNDECIDED_HUNK = 1 << 1,
1358                 ALLOW_GOTO_NEXT_HUNK = 1 << 2,
1359                 ALLOW_GOTO_NEXT_UNDECIDED_HUNK = 1 << 3,
1360                 ALLOW_SEARCH_AND_GOTO = 1 << 4,
1361                 ALLOW_SPLIT = 1 << 5,
1362                 ALLOW_EDIT = 1 << 6
1363         } permitted = 0;
1364
1365         if (!file_diff->hunk_nr)
1366                 return 0;
1367
1368         strbuf_reset(&s->buf);
1369         render_diff_header(s, file_diff, colored, &s->buf);
1370         fputs(s->buf.buf, stdout);
1371         for (;;) {
1372                 if (hunk_index >= file_diff->hunk_nr)
1373                         hunk_index = 0;
1374                 hunk = file_diff->hunk + hunk_index;
1375
1376                 undecided_previous = -1;
1377                 for (i = hunk_index - 1; i >= 0; i--)
1378                         if (file_diff->hunk[i].use == UNDECIDED_HUNK) {
1379                                 undecided_previous = i;
1380                                 break;
1381                         }
1382
1383                 undecided_next = -1;
1384                 for (i = hunk_index + 1; i < file_diff->hunk_nr; i++)
1385                         if (file_diff->hunk[i].use == UNDECIDED_HUNK) {
1386                                 undecided_next = i;
1387                                 break;
1388                         }
1389
1390                 /* Everything decided? */
1391                 if (undecided_previous < 0 && undecided_next < 0 &&
1392                     hunk->use != UNDECIDED_HUNK)
1393                         break;
1394
1395                 strbuf_reset(&s->buf);
1396                 render_hunk(s, hunk, 0, colored, &s->buf);
1397                 fputs(s->buf.buf, stdout);
1398
1399                 strbuf_reset(&s->buf);
1400                 if (undecided_previous >= 0) {
1401                         permitted |= ALLOW_GOTO_PREVIOUS_UNDECIDED_HUNK;
1402                         strbuf_addstr(&s->buf, ",k");
1403                 }
1404                 if (hunk_index) {
1405                         permitted |= ALLOW_GOTO_PREVIOUS_HUNK;
1406                         strbuf_addstr(&s->buf, ",K");
1407                 }
1408                 if (undecided_next >= 0) {
1409                         permitted |= ALLOW_GOTO_NEXT_UNDECIDED_HUNK;
1410                         strbuf_addstr(&s->buf, ",j");
1411                 }
1412                 if (hunk_index + 1 < file_diff->hunk_nr) {
1413                         permitted |= ALLOW_GOTO_NEXT_HUNK;
1414                         strbuf_addstr(&s->buf, ",J");
1415                 }
1416                 if (file_diff->hunk_nr > 1) {
1417                         permitted |= ALLOW_SEARCH_AND_GOTO;
1418                         strbuf_addstr(&s->buf, ",g,/");
1419                 }
1420                 if (hunk->splittable_into > 1) {
1421                         permitted |= ALLOW_SPLIT;
1422                         strbuf_addstr(&s->buf, ",s");
1423                 }
1424                 if (hunk_index + 1 > file_diff->mode_change &&
1425                     !file_diff->deleted) {
1426                         permitted |= ALLOW_EDIT;
1427                         strbuf_addstr(&s->buf, ",e");
1428                 }
1429                 if (file_diff->deleted)
1430                         prompt_mode_type = PROMPT_DELETION;
1431                 else if (file_diff->added)
1432                         prompt_mode_type = PROMPT_ADDITION;
1433                 else if (file_diff->mode_change && !hunk_index)
1434                         prompt_mode_type = PROMPT_MODE_CHANGE;
1435                 else
1436                         prompt_mode_type = PROMPT_HUNK;
1437
1438                 color_fprintf(stdout, s->s.prompt_color,
1439                               "(%"PRIuMAX"/%"PRIuMAX") ",
1440                               (uintmax_t)hunk_index + 1,
1441                               (uintmax_t)file_diff->hunk_nr);
1442                 color_fprintf(stdout, s->s.prompt_color,
1443                               _(s->mode->prompt_mode[prompt_mode_type]),
1444                               s->buf.buf);
1445                 fflush(stdout);
1446                 if (read_single_character(s) == EOF)
1447                         break;
1448
1449                 if (!s->answer.len)
1450                         continue;
1451                 ch = tolower(s->answer.buf[0]);
1452                 if (ch == 'y') {
1453                         hunk->use = USE_HUNK;
1454 soft_increment:
1455                         hunk_index = undecided_next < 0 ?
1456                                 file_diff->hunk_nr : undecided_next;
1457                 } else if (ch == 'n') {
1458                         hunk->use = SKIP_HUNK;
1459                         goto soft_increment;
1460                 } else if (ch == 'a') {
1461                         for (; hunk_index < file_diff->hunk_nr; hunk_index++) {
1462                                 hunk = file_diff->hunk + hunk_index;
1463                                 if (hunk->use == UNDECIDED_HUNK)
1464                                         hunk->use = USE_HUNK;
1465                         }
1466                 } else if (ch == 'd' || ch == 'q') {
1467                         for (; hunk_index < file_diff->hunk_nr; hunk_index++) {
1468                                 hunk = file_diff->hunk + hunk_index;
1469                                 if (hunk->use == UNDECIDED_HUNK)
1470                                         hunk->use = SKIP_HUNK;
1471                         }
1472                         if (ch == 'q') {
1473                                 quit = 1;
1474                                 break;
1475                         }
1476                 } else if (s->answer.buf[0] == 'K') {
1477                         if (permitted & ALLOW_GOTO_PREVIOUS_HUNK)
1478                                 hunk_index--;
1479                         else
1480                                 err(s, _("No previous hunk"));
1481                 } else if (s->answer.buf[0] == 'J') {
1482                         if (permitted & ALLOW_GOTO_NEXT_HUNK)
1483                                 hunk_index++;
1484                         else
1485                                 err(s, _("No next hunk"));
1486                 } else if (s->answer.buf[0] == 'k') {
1487                         if (permitted & ALLOW_GOTO_PREVIOUS_UNDECIDED_HUNK)
1488                                 hunk_index = undecided_previous;
1489                         else
1490                                 err(s, _("No previous hunk"));
1491                 } else if (s->answer.buf[0] == 'j') {
1492                         if (permitted & ALLOW_GOTO_NEXT_UNDECIDED_HUNK)
1493                                 hunk_index = undecided_next;
1494                         else
1495                                 err(s, _("No next hunk"));
1496                 } else if (s->answer.buf[0] == 'g') {
1497                         char *pend;
1498                         unsigned long response;
1499
1500                         if (!(permitted & ALLOW_SEARCH_AND_GOTO)) {
1501                                 err(s, _("No other hunks to goto"));
1502                                 continue;
1503                         }
1504                         strbuf_remove(&s->answer, 0, 1);
1505                         strbuf_trim(&s->answer);
1506                         i = hunk_index - DISPLAY_HUNKS_LINES / 2;
1507                         if (i < file_diff->mode_change)
1508                                 i = file_diff->mode_change;
1509                         while (s->answer.len == 0) {
1510                                 i = display_hunks(s, file_diff, i);
1511                                 printf("%s", i < file_diff->hunk_nr ?
1512                                        _("go to which hunk (<ret> to see "
1513                                          "more)? ") : _("go to which hunk? "));
1514                                 fflush(stdout);
1515                                 if (strbuf_getline(&s->answer,
1516                                                    stdin) == EOF)
1517                                         break;
1518                                 strbuf_trim_trailing_newline(&s->answer);
1519                         }
1520
1521                         strbuf_trim(&s->answer);
1522                         response = strtoul(s->answer.buf, &pend, 10);
1523                         if (*pend || pend == s->answer.buf)
1524                                 err(s, _("Invalid number: '%s'"),
1525                                     s->answer.buf);
1526                         else if (0 < response && response <= file_diff->hunk_nr)
1527                                 hunk_index = response - 1;
1528                         else
1529                                 err(s, Q_("Sorry, only %d hunk available.",
1530                                           "Sorry, only %d hunks available.",
1531                                           file_diff->hunk_nr),
1532                                     (int)file_diff->hunk_nr);
1533                 } else if (s->answer.buf[0] == '/') {
1534                         regex_t regex;
1535                         int ret;
1536
1537                         if (!(permitted & ALLOW_SEARCH_AND_GOTO)) {
1538                                 err(s, _("No other hunks to search"));
1539                                 continue;
1540                         }
1541                         strbuf_remove(&s->answer, 0, 1);
1542                         strbuf_trim_trailing_newline(&s->answer);
1543                         if (s->answer.len == 0) {
1544                                 printf("%s", _("search for regex? "));
1545                                 fflush(stdout);
1546                                 if (strbuf_getline(&s->answer,
1547                                                    stdin) == EOF)
1548                                         break;
1549                                 strbuf_trim_trailing_newline(&s->answer);
1550                                 if (s->answer.len == 0)
1551                                         continue;
1552                         }
1553                         ret = regcomp(&regex, s->answer.buf,
1554                                       REG_EXTENDED | REG_NOSUB | REG_NEWLINE);
1555                         if (ret) {
1556                                 char errbuf[1024];
1557
1558                                 regerror(ret, &regex, errbuf, sizeof(errbuf));
1559                                 err(s, _("Malformed search regexp %s: %s"),
1560                                     s->answer.buf, errbuf);
1561                                 continue;
1562                         }
1563                         i = hunk_index;
1564                         for (;;) {
1565                                 /* render the hunk into a scratch buffer */
1566                                 render_hunk(s, file_diff->hunk + i, 0, 0,
1567                                             &s->buf);
1568                                 if (regexec(&regex, s->buf.buf, 0, NULL, 0)
1569                                     != REG_NOMATCH)
1570                                         break;
1571                                 i++;
1572                                 if (i == file_diff->hunk_nr)
1573                                         i = 0;
1574                                 if (i != hunk_index)
1575                                         continue;
1576                                 err(s, _("No hunk matches the given pattern"));
1577                                 break;
1578                         }
1579                         hunk_index = i;
1580                 } else if (s->answer.buf[0] == 's') {
1581                         size_t splittable_into = hunk->splittable_into;
1582                         if (!(permitted & ALLOW_SPLIT))
1583                                 err(s, _("Sorry, cannot split this hunk"));
1584                         else if (!split_hunk(s, file_diff,
1585                                              hunk - file_diff->hunk))
1586                                 color_fprintf_ln(stdout, s->s.header_color,
1587                                                  _("Split into %d hunks."),
1588                                                  (int)splittable_into);
1589                 } else if (s->answer.buf[0] == 'e') {
1590                         if (!(permitted & ALLOW_EDIT))
1591                                 err(s, _("Sorry, cannot edit this hunk"));
1592                         else if (edit_hunk_loop(s, file_diff, hunk) >= 0) {
1593                                 hunk->use = USE_HUNK;
1594                                 goto soft_increment;
1595                         }
1596                 } else {
1597                         const char *p = _(help_patch_remainder), *eol = p;
1598
1599                         color_fprintf(stdout, s->s.help_color, "%s",
1600                                       _(s->mode->help_patch_text));
1601
1602                         /*
1603                          * Show only those lines of the remainder that are
1604                          * actually applicable with the current hunk.
1605                          */
1606                         for (; *p; p = eol + (*eol == '\n')) {
1607                                 eol = strchrnul(p, '\n');
1608
1609                                 /*
1610                                  * `s->buf` still contains the part of the
1611                                  * commands shown in the prompt that are not
1612                                  * always available.
1613                                  */
1614                                 if (*p != '?' && !strchr(s->buf.buf, *p))
1615                                         continue;
1616
1617                                 color_fprintf_ln(stdout, s->s.help_color,
1618                                                  "%.*s", (int)(eol - p), p);
1619                         }
1620                 }
1621         }
1622
1623         /* Any hunk to be used? */
1624         for (i = 0; i < file_diff->hunk_nr; i++)
1625                 if (file_diff->hunk[i].use == USE_HUNK)
1626                         break;
1627
1628         if (i < file_diff->hunk_nr) {
1629                 /* At least one hunk selected: apply */
1630                 strbuf_reset(&s->buf);
1631                 reassemble_patch(s, file_diff, 0, &s->buf);
1632
1633                 discard_index(s->s.r->index);
1634                 if (s->mode->apply_for_checkout)
1635                         apply_for_checkout(s, &s->buf,
1636                                            s->mode->is_reverse);
1637                 else {
1638                         setup_child_process(s, &cp, "apply", NULL);
1639                         strvec_pushv(&cp.args, s->mode->apply_args);
1640                         if (pipe_command(&cp, s->buf.buf, s->buf.len,
1641                                          NULL, 0, NULL, 0))
1642                                 error(_("'git apply' failed"));
1643                 }
1644                 if (!repo_read_index(s->s.r))
1645                         repo_refresh_and_write_index(s->s.r, REFRESH_QUIET, 0,
1646                                                      1, NULL, NULL, NULL);
1647         }
1648
1649         putchar('\n');
1650         return quit;
1651 }
1652
1653 int run_add_p(struct repository *r, enum add_p_mode mode,
1654               const char *revision, const struct pathspec *ps)
1655 {
1656         struct add_p_state s = {
1657                 { r }, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
1658         };
1659         size_t i, binary_count = 0;
1660
1661         init_add_i_state(&s.s, r);
1662
1663         if (mode == ADD_P_STASH)
1664                 s.mode = &patch_mode_stash;
1665         else if (mode == ADD_P_RESET) {
1666                 if (!revision || !strcmp(revision, "HEAD"))
1667                         s.mode = &patch_mode_reset_head;
1668                 else
1669                         s.mode = &patch_mode_reset_nothead;
1670         } else if (mode == ADD_P_CHECKOUT) {
1671                 if (!revision)
1672                         s.mode = &patch_mode_checkout_index;
1673                 else if (!strcmp(revision, "HEAD"))
1674                         s.mode = &patch_mode_checkout_head;
1675                 else
1676                         s.mode = &patch_mode_checkout_nothead;
1677         } else if (mode == ADD_P_WORKTREE) {
1678                 if (!revision)
1679                         s.mode = &patch_mode_checkout_index;
1680                 else if (!strcmp(revision, "HEAD"))
1681                         s.mode = &patch_mode_worktree_head;
1682                 else
1683                         s.mode = &patch_mode_worktree_nothead;
1684         } else
1685                 s.mode = &patch_mode_add;
1686         s.revision = revision;
1687
1688         if (discard_index(r->index) < 0 || repo_read_index(r) < 0 ||
1689             (!s.mode->index_only &&
1690              repo_refresh_and_write_index(r, REFRESH_QUIET, 0, 1,
1691                                           NULL, NULL, NULL) < 0) ||
1692             parse_diff(&s, ps) < 0) {
1693                 strbuf_release(&s.plain);
1694                 strbuf_release(&s.colored);
1695                 clear_add_i_state(&s.s);
1696                 return -1;
1697         }
1698
1699         for (i = 0; i < s.file_diff_nr; i++)
1700                 if (s.file_diff[i].binary && !s.file_diff[i].hunk_nr)
1701                         binary_count++;
1702                 else if (patch_update_file(&s, s.file_diff + i))
1703                         break;
1704
1705         if (s.file_diff_nr == 0)
1706                 fprintf(stderr, _("No changes.\n"));
1707         else if (binary_count == s.file_diff_nr)
1708                 fprintf(stderr, _("Only binary files changed.\n"));
1709
1710         strbuf_release(&s.answer);
1711         strbuf_release(&s.buf);
1712         strbuf_release(&s.plain);
1713         strbuf_release(&s.colored);
1714         clear_add_i_state(&s.s);
1715         return 0;
1716 }