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   1 /*
   2  * Builtin "git am"
   3  *
   4  * Based on git-am.sh by Junio C Hamano.
   5  */
   6 #include "cache.h"
   7 #include "config.h"
   8 #include "builtin.h"
   9 #include "exec-cmd.h"
  10 #include "parse-options.h"
  11 #include "dir.h"
  12 #include "run-command.h"
  13 #include "quote.h"
  14 #include "tempfile.h"
  15 #include "lockfile.h"
  16 #include "cache-tree.h"
  17 #include "refs.h"
  18 #include "commit.h"
  19 #include "diff.h"
  20 #include "diffcore.h"
  21 #include "unpack-trees.h"
  22 #include "branch.h"
  23 #include "sequencer.h"
  24 #include "revision.h"
  25 #include "merge-recursive.h"
  26 #include "revision.h"
  27 #include "log-tree.h"
  28 #include "notes-utils.h"
  29 #include "rerere.h"
  30 #include "prompt.h"
  31 #include "mailinfo.h"
  32 #include "apply.h"
  33 #include "string-list.h"
  34 #include "packfile.h"
  35 #include "repository.h"
  36
  37 /**
  38  * Returns 1 if the file is empty or does not exist, 0 otherwise.
  39  */
  40 static int is_empty_file(const char *filename)
  41 {
  42         struct stat st;
  43
  44         if (stat(filename, &st) < 0) {
  45                 if (errno == ENOENT)
  46                         return 1;
  47                 die_errno(_("could not stat %s"), filename);
  48         }
  49
  50         return !st.st_size;
  51 }
  52
  53 /**
  54  * Returns the length of the first line of msg.
  55  */
  56 static int linelen(const char *msg)
  57 {
  58         return strchrnul(msg, '\n') - msg;
  59 }
  60
  61 /**
  62  * Returns true if `str` consists of only whitespace, false otherwise.
  63  */
  64 static int str_isspace(const char *str)
  65 {
  66         for (; *str; str++)
  67                 if (!isspace(*str))
  68                         return 0;
  69
  70         return 1;
  71 }
  72
  73 enum patch_format {
  74         PATCH_FORMAT_UNKNOWN = 0,
  75         PATCH_FORMAT_MBOX,
  76         PATCH_FORMAT_STGIT,
  77         PATCH_FORMAT_STGIT_SERIES,
  78         PATCH_FORMAT_HG,
  79         PATCH_FORMAT_MBOXRD
  80 };
  81
  82 enum keep_type {
  83         KEEP_FALSE = 0,
  84         KEEP_TRUE,      /* pass -k flag to git-mailinfo */
  85         KEEP_NON_PATCH  /* pass -b flag to git-mailinfo */
  86 };
  87
  88 enum scissors_type {
  89         SCISSORS_UNSET = -1,
  90         SCISSORS_FALSE = 0,  /* pass --no-scissors to git-mailinfo */
  91         SCISSORS_TRUE        /* pass --scissors to git-mailinfo */
  92 };
  93
  94 enum signoff_type {
  95         SIGNOFF_FALSE = 0,
  96         SIGNOFF_TRUE = 1,
  97         SIGNOFF_EXPLICIT /* --signoff was set on the command-line */
  98 };
  99
 100 struct am_state {
 101         /* state directory path */
 102         char *dir;
 103
 104         /* current and last patch numbers, 1-indexed */
 105         int cur;
 106         int last;
 107
 108         /* commit metadata and message */
 109         char *author_name;
 110         char *author_email;
 111         char *author_date;
 112         char *msg;
 113         size_t msg_len;
 114
 115         /* when --rebasing, records the original commit the patch came from */
 116         struct object_id orig_commit;
 117
 118         /* number of digits in patch filename */
 119         int prec;
 120
 121         /* various operating modes and command line options */
 122         int interactive;
 123         int threeway;
 124         int quiet;
 125         int signoff; /* enum signoff_type */
 126         int utf8;
 127         int keep; /* enum keep_type */
 128         int message_id;
 129         int scissors; /* enum scissors_type */
 130         struct argv_array git_apply_opts;
 131         const char *resolvemsg;
 132         int committer_date_is_author_date;
 133         int ignore_date;
 134         int allow_rerere_autoupdate;
 135         const char *sign_commit;
 136         int rebasing;
 137 };
 138
 139 /**
 140  * Initializes am_state with the default values.
 141  */
 142 static void am_state_init(struct am_state *state)
 143 {
 144         int gpgsign;
 145
 146         memset(state, 0, sizeof(*state));
 147
 148         state->dir = git_pathdup("rebase-apply");
 149
 150         state->prec = 4;
 151
 152         git_config_get_bool("am.threeway", &state->threeway);
 153
 154         state->utf8 = 1;
 155
 156         git_config_get_bool("am.messageid", &state->message_id);
 157
 158         state->scissors = SCISSORS_UNSET;
 159
 160         argv_array_init(&state->git_apply_opts);
 161
 162         if (!git_config_get_bool("commit.gpgsign", &gpgsign))
 163                 state->sign_commit = gpgsign ? "" : NULL;
 164 }
 165
 166 /**
 167  * Releases memory allocated by an am_state.
 168  */
 169 static void am_state_release(struct am_state *state)
 170 {
 171         free(state->dir);
 172         free(state->author_name);
 173         free(state->author_email);
 174         free(state->author_date);
 175         free(state->msg);
 176         argv_array_clear(&state->git_apply_opts);
 177 }
 178
 179 /**
 180  * Returns path relative to the am_state directory.
 181  */
 182 static inline const char *am_path(const struct am_state *state, const char *path)
 183 {
 184         return mkpath("%s/%s", state->dir, path);
 185 }
 186
 187 /**
 188  * For convenience to call write_file()
 189  */
 190 static void write_state_text(const struct am_state *state,
 191                              const char *name, const char *string)
 192 {
 193         write_file(am_path(state, name), "%s", string);
 194 }
 195
 196 static void write_state_count(const struct am_state *state,
 197                               const char *name, int value)
 198 {
 199         write_file(am_path(state, name), "%d", value);
 200 }
 201
 202 static void write_state_bool(const struct am_state *state,
 203                              const char *name, int value)
 204 {
 205         write_state_text(state, name, value ? "t" : "f");
 206 }
 207
 208 /**
 209  * If state->quiet is false, calls fprintf(fp, fmt, ...), and appends a newline
 210  * at the end.
 211  */
 212 static void say(const struct am_state *state, FILE *fp, const char *fmt, ...)
 213 {
 214         va_list ap;
 215
 216         va_start(ap, fmt);
 217         if (!state->quiet) {
 218                 vfprintf(fp, fmt, ap);
 219                 putc('\n', fp);
 220         }
 221         va_end(ap);
 222 }
 223
 224 /**
 225  * Returns 1 if there is an am session in progress, 0 otherwise.
 226  */
 227 static int am_in_progress(const struct am_state *state)
 228 {
 229         struct stat st;
 230
 231         if (lstat(state->dir, &st) < 0 || !S_ISDIR(st.st_mode))
 232                 return 0;
 233         if (lstat(am_path(state, "last"), &st) || !S_ISREG(st.st_mode))
 234                 return 0;
 235         if (lstat(am_path(state, "next"), &st) || !S_ISREG(st.st_mode))
 236                 return 0;
 237         return 1;
 238 }
 239
 240 /**
 241  * Reads the contents of `file` in the `state` directory into `sb`. Returns the
 242  * number of bytes read on success, -1 if the file does not exist. If `trim` is
 243  * set, trailing whitespace will be removed.
 244  */
 245 static int read_state_file(struct strbuf *sb, const struct am_state *state,
 246                         const char *file, int trim)
 247 {
 248         strbuf_reset(sb);
 249
 250         if (strbuf_read_file(sb, am_path(state, file), 0) >= 0) {
 251                 if (trim)
 252                         strbuf_trim(sb);
 253
 254                 return sb->len;
 255         }
 256
 257         if (errno == ENOENT)
 258                 return -1;
 259
 260         die_errno(_("could not read '%s'"), am_path(state, file));
 261 }
 262
 263 /**
 264  * Reads and parses the state directory's "author-script" file, and sets
 265  * state->author_name, state->author_email and state->author_date accordingly.
 266  * Returns 0 on success, -1 if the file could not be parsed.
 267  *
 268  * The author script is of the format:
 269  *
 270  *      GIT_AUTHOR_NAME='$author_name'
 271  *      GIT_AUTHOR_EMAIL='$author_email'
 272  *      GIT_AUTHOR_DATE='$author_date'
 273  *
 274  * where $author_name, $author_email and $author_date are quoted. We are strict
 275  * with our parsing, as the file was meant to be eval'd in the old git-am.sh
 276  * script, and thus if the file differs from what this function expects, it is
 277  * better to bail out than to do something that the user does not expect.
 278  */
 279 static int read_am_author_script(struct am_state *state)
 280 {
 281         const char *filename = am_path(state, "author-script");
 282
 283         assert(!state->author_name);
 284         assert(!state->author_email);
 285         assert(!state->author_date);
 286
 287         return read_author_script(filename, &state->author_name,
 288                                   &state->author_email, &state->author_date, 1);
 289 }
 290
 291 /**
 292  * Saves state->author_name, state->author_email and state->author_date in the
 293  * state directory's "author-script" file.
 294  */
 295 static void write_author_script(const struct am_state *state)
 296 {
 297         struct strbuf sb = STRBUF_INIT;
 298
 299         strbuf_addstr(&sb, "GIT_AUTHOR_NAME=");
 300         sq_quote_buf(&sb, state->author_name);
 301         strbuf_addch(&sb, '\n');
 302
 303         strbuf_addstr(&sb, "GIT_AUTHOR_EMAIL=");
 304         sq_quote_buf(&sb, state->author_email);
 305         strbuf_addch(&sb, '\n');
 306
 307         strbuf_addstr(&sb, "GIT_AUTHOR_DATE=");
 308         sq_quote_buf(&sb, state->author_date);
 309         strbuf_addch(&sb, '\n');
 310
 311         write_state_text(state, "author-script", sb.buf);
 312
 313         strbuf_release(&sb);
 314 }
 315
 316 /**
 317  * Reads the commit message from the state directory's "final-commit" file,
 318  * setting state->msg to its contents and state->msg_len to the length of its
 319  * contents in bytes.
 320  *
 321  * Returns 0 on success, -1 if the file does not exist.
 322  */
 323 static int read_commit_msg(struct am_state *state)
 324 {
 325         struct strbuf sb = STRBUF_INIT;
 326
 327         assert(!state->msg);
 328
 329         if (read_state_file(&sb, state, "final-commit", 0) < 0) {
 330                 strbuf_release(&sb);
 331                 return -1;
 332         }
 333
 334         state->msg = strbuf_detach(&sb, &state->msg_len);
 335         return 0;
 336 }
 337
 338 /**
 339  * Saves state->msg in the state directory's "final-commit" file.
 340  */
 341 static void write_commit_msg(const struct am_state *state)
 342 {
 343         const char *filename = am_path(state, "final-commit");
 344         write_file_buf(filename, state->msg, state->msg_len);
 345 }
 346
 347 /**
 348  * Loads state from disk.
 349  */
 350 static void am_load(struct am_state *state)
 351 {
 352         struct strbuf sb = STRBUF_INIT;
 353
 354         if (read_state_file(&sb, state, "next", 1) < 0)
 355                 BUG("state file 'next' does not exist");
 356         state->cur = strtol(sb.buf, NULL, 10);
 357
 358         if (read_state_file(&sb, state, "last", 1) < 0)
 359                 BUG("state file 'last' does not exist");
 360         state->last = strtol(sb.buf, NULL, 10);
 361
 362         if (read_am_author_script(state) < 0)
 363                 die(_("could not parse author script"));
 364
 365         read_commit_msg(state);
 366
 367         if (read_state_file(&sb, state, "original-commit", 1) < 0)
 368                 oidclr(&state->orig_commit);
 369         else if (get_oid_hex(sb.buf, &state->orig_commit) < 0)
 370                 die(_("could not parse %s"), am_path(state, "original-commit"));
 371
 372         read_state_file(&sb, state, "threeway", 1);
 373         state->threeway = !strcmp(sb.buf, "t");
 374
 375         read_state_file(&sb, state, "quiet", 1);
 376         state->quiet = !strcmp(sb.buf, "t");
 377
 378         read_state_file(&sb, state, "sign", 1);
 379         state->signoff = !strcmp(sb.buf, "t");
 380
 381         read_state_file(&sb, state, "utf8", 1);
 382         state->utf8 = !strcmp(sb.buf, "t");
 383
 384         if (file_exists(am_path(state, "rerere-autoupdate"))) {
 385                 read_state_file(&sb, state, "rerere-autoupdate", 1);
 386                 state->allow_rerere_autoupdate = strcmp(sb.buf, "t") ?
 387                         RERERE_NOAUTOUPDATE : RERERE_AUTOUPDATE;
 388         } else {
 389                 state->allow_rerere_autoupdate = 0;
 390         }
 391
 392         read_state_file(&sb, state, "keep", 1);
 393         if (!strcmp(sb.buf, "t"))
 394                 state->keep = KEEP_TRUE;
 395         else if (!strcmp(sb.buf, "b"))
 396                 state->keep = KEEP_NON_PATCH;
 397         else
 398                 state->keep = KEEP_FALSE;
 399
 400         read_state_file(&sb, state, "messageid", 1);
 401         state->message_id = !strcmp(sb.buf, "t");
 402
 403         read_state_file(&sb, state, "scissors", 1);
 404         if (!strcmp(sb.buf, "t"))
 405                 state->scissors = SCISSORS_TRUE;
 406         else if (!strcmp(sb.buf, "f"))
 407                 state->scissors = SCISSORS_FALSE;
 408         else
 409                 state->scissors = SCISSORS_UNSET;
 410
 411         read_state_file(&sb, state, "apply-opt", 1);
 412         argv_array_clear(&state->git_apply_opts);
 413         if (sq_dequote_to_argv_array(sb.buf, &state->git_apply_opts) < 0)
 414                 die(_("could not parse %s"), am_path(state, "apply-opt"));
 415
 416         state->rebasing = !!file_exists(am_path(state, "rebasing"));
 417
 418         strbuf_release(&sb);
 419 }
 420
 421 /**
 422  * Removes the am_state directory, forcefully terminating the current am
 423  * session.
 424  */
 425 static void am_destroy(const struct am_state *state)
 426 {
 427         struct strbuf sb = STRBUF_INIT;
 428
 429         strbuf_addstr(&sb, state->dir);
 430         remove_dir_recursively(&sb, 0);
 431         strbuf_release(&sb);
 432 }
 433
 434 /**
 435  * Runs applypatch-msg hook. Returns its exit code.
 436  */
 437 static int run_applypatch_msg_hook(struct am_state *state)
 438 {
 439         int ret;
 440
 441         assert(state->msg);
 442         ret = run_hook_le(NULL, "applypatch-msg", am_path(state, "final-commit"), NULL);
 443
 444         if (!ret) {
 445                 FREE_AND_NULL(state->msg);
 446                 if (read_commit_msg(state) < 0)
 447                         die(_("'%s' was deleted by the applypatch-msg hook"),
 448                                 am_path(state, "final-commit"));
 449         }
 450
 451         return ret;
 452 }
 453
 454 /**
 455  * Runs post-rewrite hook. Returns it exit code.
 456  */
 457 static int run_post_rewrite_hook(const struct am_state *state)
 458 {
 459         struct child_process cp = CHILD_PROCESS_INIT;
 460         const char *hook = find_hook("post-rewrite");
 461         int ret;
 462
 463         if (!hook)
 464                 return 0;
 465
 466         argv_array_push(&cp.args, hook);
 467         argv_array_push(&cp.args, "rebase");
 468
 469         cp.in = xopen(am_path(state, "rewritten"), O_RDONLY);
 470         cp.stdout_to_stderr = 1;
 471
 472         ret = run_command(&cp);
 473
 474         close(cp.in);
 475         return ret;
 476 }
 477
 478 /**
 479  * Reads the state directory's "rewritten" file, and copies notes from the old
 480  * commits listed in the file to their rewritten commits.
 481  *
 482  * Returns 0 on success, -1 on failure.
 483  */
 484 static int copy_notes_for_rebase(const struct am_state *state)
 485 {
 486         struct notes_rewrite_cfg *c;
 487         struct strbuf sb = STRBUF_INIT;
 488         const char *invalid_line = _("Malformed input line: '%s'.");
 489         const char *msg = "Notes added by 'git rebase'";
 490         FILE *fp;
 491         int ret = 0;
 492
 493         assert(state->rebasing);
 494
 495         c = init_copy_notes_for_rewrite("rebase");
 496         if (!c)
 497                 return 0;
 498
 499         fp = xfopen(am_path(state, "rewritten"), "r");
 500
 501         while (!strbuf_getline_lf(&sb, fp)) {
 502                 struct object_id from_obj, to_obj;
 503
 504                 if (sb.len != GIT_SHA1_HEXSZ * 2 + 1) {
 505                         ret = error(invalid_line, sb.buf);
 506                         goto finish;
 507                 }
 508
 509                 if (get_oid_hex(sb.buf, &from_obj)) {
 510                         ret = error(invalid_line, sb.buf);
 511                         goto finish;
 512                 }
 513
 514                 if (sb.buf[GIT_SHA1_HEXSZ] != ' ') {
 515                         ret = error(invalid_line, sb.buf);
 516                         goto finish;
 517                 }
 518
 519                 if (get_oid_hex(sb.buf + GIT_SHA1_HEXSZ + 1, &to_obj)) {
 520                         ret = error(invalid_line, sb.buf);
 521                         goto finish;
 522                 }
 523
 524                 if (copy_note_for_rewrite(c, &from_obj, &to_obj))
 525                         ret = error(_("Failed to copy notes from '%s' to '%s'"),
 526                                         oid_to_hex(&from_obj), oid_to_hex(&to_obj));
 527         }
 528
 529 finish:
 530         finish_copy_notes_for_rewrite(c, msg);
 531         fclose(fp);
 532         strbuf_release(&sb);
 533         return ret;
 534 }
 535
 536 /**
 537  * Determines if the file looks like a piece of RFC2822 mail by grabbing all
 538  * non-indented lines and checking if they look like they begin with valid
 539  * header field names.
 540  *
 541  * Returns 1 if the file looks like a piece of mail, 0 otherwise.
 542  */
 543 static int is_mail(FILE *fp)
 544 {
 545         const char *header_regex = "^[!-9;-~]+:";
 546         struct strbuf sb = STRBUF_INIT;
 547         regex_t regex;
 548         int ret = 1;
 549
 550         if (fseek(fp, 0L, SEEK_SET))
 551                 die_errno(_("fseek failed"));
 552
 553         if (regcomp(&regex, header_regex, REG_NOSUB | REG_EXTENDED))
 554                 die("invalid pattern: %s", header_regex);
 555
 556         while (!strbuf_getline(&sb, fp)) {
 557                 if (!sb.len)
 558                         break; /* End of header */
 559
 560                 /* Ignore indented folded lines */
 561                 if (*sb.buf == '\t' || *sb.buf == ' ')
 562                         continue;
 563
 564                 /* It's a header if it matches header_regex */
 565                 if (regexec(&regex, sb.buf, 0, NULL, 0)) {
 566                         ret = 0;
 567                         goto done;
 568                 }
 569         }
 570
 571 done:
 572         regfree(&regex);
 573         strbuf_release(&sb);
 574         return ret;
 575 }
 576
 577 /**
 578  * Attempts to detect the patch_format of the patches contained in `paths`,
 579  * returning the PATCH_FORMAT_* enum value. Returns PATCH_FORMAT_UNKNOWN if
 580  * detection fails.
 581  */
 582 static int detect_patch_format(const char **paths)
 583 {
 584         enum patch_format ret = PATCH_FORMAT_UNKNOWN;
 585         struct strbuf l1 = STRBUF_INIT;
 586         struct strbuf l2 = STRBUF_INIT;
 587         struct strbuf l3 = STRBUF_INIT;
 588         FILE *fp;
 589
 590         /*
 591          * We default to mbox format if input is from stdin and for directories
 592          */
 593         if (!*paths || !strcmp(*paths, "-") || is_directory(*paths))
 594                 return PATCH_FORMAT_MBOX;
 595
 596         /*
 597          * Otherwise, check the first few lines of the first patch, starting
 598          * from the first non-blank line, to try to detect its format.
 599          */
 600
 601         fp = xfopen(*paths, "r");
 602
 603         while (!strbuf_getline(&l1, fp)) {
 604                 if (l1.len)
 605                         break;
 606         }
 607
 608         if (starts_with(l1.buf, "From ") || starts_with(l1.buf, "From: ")) {
 609                 ret = PATCH_FORMAT_MBOX;
 610                 goto done;
 611         }
 612
 613         if (starts_with(l1.buf, "# This series applies on GIT commit")) {
 614                 ret = PATCH_FORMAT_STGIT_SERIES;
 615                 goto done;
 616         }
 617
 618         if (!strcmp(l1.buf, "# HG changeset patch")) {
 619                 ret = PATCH_FORMAT_HG;
 620                 goto done;
 621         }
 622
 623         strbuf_getline(&l2, fp);
 624         strbuf_getline(&l3, fp);
 625
 626         /*
 627          * If the second line is empty and the third is a From, Author or Date
 628          * entry, this is likely an StGit patch.
 629          */
 630         if (l1.len && !l2.len &&
 631                 (starts_with(l3.buf, "From:") ||
 632                  starts_with(l3.buf, "Author:") ||
 633                  starts_with(l3.buf, "Date:"))) {
 634                 ret = PATCH_FORMAT_STGIT;
 635                 goto done;
 636         }
 637
 638         if (l1.len && is_mail(fp)) {
 639                 ret = PATCH_FORMAT_MBOX;
 640                 goto done;
 641         }
 642
 643 done:
 644         fclose(fp);
 645         strbuf_release(&l1);
 646         strbuf_release(&l2);
 647         strbuf_release(&l3);
 648         return ret;
 649 }
 650
 651 /**
 652  * Splits out individual email patches from `paths`, where each path is either
 653  * a mbox file or a Maildir. Returns 0 on success, -1 on failure.
 654  */
 655 static int split_mail_mbox(struct am_state *state, const char **paths,
 656                                 int keep_cr, int mboxrd)
 657 {
 658         struct child_process cp = CHILD_PROCESS_INIT;
 659         struct strbuf last = STRBUF_INIT;
 660         int ret;
 661
 662         cp.git_cmd = 1;
 663         argv_array_push(&cp.args, "mailsplit");
 664         argv_array_pushf(&cp.args, "-d%d", state->prec);
 665         argv_array_pushf(&cp.args, "-o%s", state->dir);
 666         argv_array_push(&cp.args, "-b");
 667         if (keep_cr)
 668                 argv_array_push(&cp.args, "--keep-cr");
 669         if (mboxrd)
 670                 argv_array_push(&cp.args, "--mboxrd");
 671         argv_array_push(&cp.args, "--");
 672         argv_array_pushv(&cp.args, paths);
 673
 674         ret = capture_command(&cp, &last, 8);
 675         if (ret)
 676                 goto exit;
 677
 678         state->cur = 1;
 679         state->last = strtol(last.buf, NULL, 10);
 680
 681 exit:
 682         strbuf_release(&last);
 683         return ret ? -1 : 0;
 684 }
 685
 686 /**
 687  * Callback signature for split_mail_conv(). The foreign patch should be
 688  * read from `in`, and the converted patch (in RFC2822 mail format) should be
 689  * written to `out`. Return 0 on success, or -1 on failure.
 690  */
 691 typedef int (*mail_conv_fn)(FILE *out, FILE *in, int keep_cr);
 692
 693 /**
 694  * Calls `fn` for each file in `paths` to convert the foreign patch to the
 695  * RFC2822 mail format suitable for parsing with git-mailinfo.
 696  *
 697  * Returns 0 on success, -1 on failure.
 698  */
 699 static int split_mail_conv(mail_conv_fn fn, struct am_state *state,
 700                         const char **paths, int keep_cr)
 701 {
 702         static const char *stdin_only[] = {"-", NULL};
 703         int i;
 704
 705         if (!*paths)
 706                 paths = stdin_only;
 707
 708         for (i = 0; *paths; paths++, i++) {
 709                 FILE *in, *out;
 710                 const char *mail;
 711                 int ret;
 712
 713                 if (!strcmp(*paths, "-"))
 714                         in = stdin;
 715                 else
 716                         in = fopen(*paths, "r");
 717
 718                 if (!in)
 719                         return error_errno(_("could not open '%s' for reading"),
 720                                            *paths);
 721
 722                 mail = mkpath("%s/%0*d", state->dir, state->prec, i + 1);
 723
 724                 out = fopen(mail, "w");
 725                 if (!out) {
 726                         if (in != stdin)
 727                                 fclose(in);
 728                         return error_errno(_("could not open '%s' for writing"),
 729                                            mail);
 730                 }
 731
 732                 ret = fn(out, in, keep_cr);
 733
 734                 fclose(out);
 735                 if (in != stdin)
 736                         fclose(in);
 737
 738                 if (ret)
 739                         return error(_("could not parse patch '%s'"), *paths);
 740         }
 741
 742         state->cur = 1;
 743         state->last = i;
 744         return 0;
 745 }
 746
 747 /**
 748  * A split_mail_conv() callback that converts an StGit patch to an RFC2822
 749  * message suitable for parsing with git-mailinfo.
 750  */
 751 static int stgit_patch_to_mail(FILE *out, FILE *in, int keep_cr)
 752 {
 753         struct strbuf sb = STRBUF_INIT;
 754         int subject_printed = 0;
 755
 756         while (!strbuf_getline_lf(&sb, in)) {
 757                 const char *str;
 758
 759                 if (str_isspace(sb.buf))
 760                         continue;
 761                 else if (skip_prefix(sb.buf, "Author:", &str))
 762                         fprintf(out, "From:%s\n", str);
 763                 else if (starts_with(sb.buf, "From") || starts_with(sb.buf, "Date"))
 764                         fprintf(out, "%s\n", sb.buf);
 765                 else if (!subject_printed) {
 766                         fprintf(out, "Subject: %s\n", sb.buf);
 767                         subject_printed = 1;
 768                 } else {
 769                         fprintf(out, "\n%s\n", sb.buf);
 770                         break;
 771                 }
 772         }
 773
 774         strbuf_reset(&sb);
 775         while (strbuf_fread(&sb, 8192, in) > 0) {
 776                 fwrite(sb.buf, 1, sb.len, out);
 777                 strbuf_reset(&sb);
 778         }
 779
 780         strbuf_release(&sb);
 781         return 0;
 782 }
 783
 784 /**
 785  * This function only supports a single StGit series file in `paths`.
 786  *
 787  * Given an StGit series file, converts the StGit patches in the series into
 788  * RFC2822 messages suitable for parsing with git-mailinfo, and queues them in
 789  * the state directory.
 790  *
 791  * Returns 0 on success, -1 on failure.
 792  */
 793 static int split_mail_stgit_series(struct am_state *state, const char **paths,
 794                                         int keep_cr)
 795 {
 796         const char *series_dir;
 797         char *series_dir_buf;
 798         FILE *fp;
 799         struct argv_array patches = ARGV_ARRAY_INIT;
 800         struct strbuf sb = STRBUF_INIT;
 801         int ret;
 802
 803         if (!paths[0] || paths[1])
 804                 return error(_("Only one StGIT patch series can be applied at once"));
 805
 806         series_dir_buf = xstrdup(*paths);
 807         series_dir = dirname(series_dir_buf);
 808
 809         fp = fopen(*paths, "r");
 810         if (!fp)
 811                 return error_errno(_("could not open '%s' for reading"), *paths);
 812
 813         while (!strbuf_getline_lf(&sb, fp)) {
 814                 if (*sb.buf == '#')
 815                         continue; /* skip comment lines */
 816
 817                 argv_array_push(&patches, mkpath("%s/%s", series_dir, sb.buf));
 818         }
 819
 820         fclose(fp);
 821         strbuf_release(&sb);
 822         free(series_dir_buf);
 823
 824         ret = split_mail_conv(stgit_patch_to_mail, state, patches.argv, keep_cr);
 825
 826         argv_array_clear(&patches);
 827         return ret;
 828 }
 829
 830 /**
 831  * A split_patches_conv() callback that converts a mercurial patch to a RFC2822
 832  * message suitable for parsing with git-mailinfo.
 833  */
 834 static int hg_patch_to_mail(FILE *out, FILE *in, int keep_cr)
 835 {
 836         struct strbuf sb = STRBUF_INIT;
 837         int rc = 0;
 838
 839         while (!strbuf_getline_lf(&sb, in)) {
 840                 const char *str;
 841
 842                 if (skip_prefix(sb.buf, "# User ", &str))
 843                         fprintf(out, "From: %s\n", str);
 844                 else if (skip_prefix(sb.buf, "# Date ", &str)) {
 845                         timestamp_t timestamp;
 846                         long tz, tz2;
 847                         char *end;
 848
 849                         errno = 0;
 850                         timestamp = parse_timestamp(str, &end, 10);
 851                         if (errno) {
 852                                 rc = error(_("invalid timestamp"));
 853                                 goto exit;
 854                         }
 855
 856                         if (!skip_prefix(end, " ", &str)) {
 857                                 rc = error(_("invalid Date line"));
 858                                 goto exit;
 859                         }
 860
 861                         errno = 0;
 862                         tz = strtol(str, &end, 10);
 863                         if (errno) {
 864                                 rc = error(_("invalid timezone offset"));
 865                                 goto exit;
 866                         }
 867
 868                         if (*end) {
 869                                 rc = error(_("invalid Date line"));
 870                                 goto exit;
 871                         }
 872
 873                         /*
 874                          * mercurial's timezone is in seconds west of UTC,
 875                          * however git's timezone is in hours + minutes east of
 876                          * UTC. Convert it.
 877                          */
 878                         tz2 = labs(tz) / 3600 * 100 + labs(tz) % 3600 / 60;
 879                         if (tz > 0)
 880                                 tz2 = -tz2;
 881
 882                         fprintf(out, "Date: %s\n", show_date(timestamp, tz2, DATE_MODE(RFC2822)));
 883                 } else if (starts_with(sb.buf, "# ")) {
 884                         continue;
 885                 } else {
 886                         fprintf(out, "\n%s\n", sb.buf);
 887                         break;
 888                 }
 889         }
 890
 891         strbuf_reset(&sb);
 892         while (strbuf_fread(&sb, 8192, in) > 0) {
 893                 fwrite(sb.buf, 1, sb.len, out);
 894                 strbuf_reset(&sb);
 895         }
 896 exit:
 897         strbuf_release(&sb);
 898         return rc;
 899 }
 900
 901 /**
 902  * Splits a list of files/directories into individual email patches. Each path
 903  * in `paths` must be a file/directory that is formatted according to
 904  * `patch_format`.
 905  *
 906  * Once split out, the individual email patches will be stored in the state
 907  * directory, with each patch's filename being its index, padded to state->prec
 908  * digits.
 909  *
 910  * state->cur will be set to the index of the first mail, and state->last will
 911  * be set to the index of the last mail.
 912  *
 913  * Set keep_cr to 0 to convert all lines ending with \r\n to end with \n, 1
 914  * to disable this behavior, -1 to use the default configured setting.
 915  *
 916  * Returns 0 on success, -1 on failure.
 917  */
 918 static int split_mail(struct am_state *state, enum patch_format patch_format,
 919                         const char **paths, int keep_cr)
 920 {
 921         if (keep_cr < 0) {
 922                 keep_cr = 0;
 923                 git_config_get_bool("am.keepcr", &keep_cr);
 924         }
 925
 926         switch (patch_format) {
 927         case PATCH_FORMAT_MBOX:
 928                 return split_mail_mbox(state, paths, keep_cr, 0);
 929         case PATCH_FORMAT_STGIT:
 930                 return split_mail_conv(stgit_patch_to_mail, state, paths, keep_cr);
 931         case PATCH_FORMAT_STGIT_SERIES:
 932                 return split_mail_stgit_series(state, paths, keep_cr);
 933         case PATCH_FORMAT_HG:
 934                 return split_mail_conv(hg_patch_to_mail, state, paths, keep_cr);
 935         case PATCH_FORMAT_MBOXRD:
 936                 return split_mail_mbox(state, paths, keep_cr, 1);
 937         default:
 938                 BUG("invalid patch_format");
 939         }
 940         return -1;
 941 }
 942
 943 /**
 944  * Setup a new am session for applying patches
 945  */
 946 static void am_setup(struct am_state *state, enum patch_format patch_format,
 947                         const char **paths, int keep_cr)
 948 {
 949         struct object_id curr_head;
 950         const char *str;
 951         struct strbuf sb = STRBUF_INIT;
 952
 953         if (!patch_format)
 954                 patch_format = detect_patch_format(paths);
 955
 956         if (!patch_format) {
 957                 fprintf_ln(stderr, _("Patch format detection failed."));
 958                 exit(128);
 959         }
 960
 961         if (mkdir(state->dir, 0777) < 0 && errno != EEXIST)
 962                 die_errno(_("failed to create directory '%s'"), state->dir);
 963         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 964
 965         if (split_mail(state, patch_format, paths, keep_cr) < 0) {
 966                 am_destroy(state);
 967                 die(_("Failed to split patches."));
 968         }
 969
 970         if (state->rebasing)
 971                 state->threeway = 1;
 972
 973         write_state_bool(state, "threeway", state->threeway);
 974         write_state_bool(state, "quiet", state->quiet);
 975         write_state_bool(state, "sign", state->signoff);
 976         write_state_bool(state, "utf8", state->utf8);
 977
 978         if (state->allow_rerere_autoupdate)
 979                 write_state_bool(state, "rerere-autoupdate",
 980                          state->allow_rerere_autoupdate == RERERE_AUTOUPDATE);
 981
 982         switch (state->keep) {
 983         case KEEP_FALSE:
 984                 str = "f";
 985                 break;
 986         case KEEP_TRUE:
 987                 str = "t";
 988                 break;
 989         case KEEP_NON_PATCH:
 990                 str = "b";
 991                 break;
 992         default:
 993                 BUG("invalid value for state->keep");
 994         }
 995
 996         write_state_text(state, "keep", str);
 997         write_state_bool(state, "messageid", state->message_id);
 998
 999         switch (state->scissors) {
1000         case SCISSORS_UNSET:
1001                 str = "";
1002                 break;
1003         case SCISSORS_FALSE:
1004                 str = "f";
1005                 break;
1006         case SCISSORS_TRUE:
1007                 str = "t";
1008                 break;
1009         default:
1010                 BUG("invalid value for state->scissors");
1011         }
1012         write_state_text(state, "scissors", str);
1013
1014         sq_quote_argv(&sb, state->git_apply_opts.argv);
1015         write_state_text(state, "apply-opt", sb.buf);
1016
1017         if (state->rebasing)
1018                 write_state_text(state, "rebasing", "");
1019         else
1020                 write_state_text(state, "applying", "");
1021
1022         if (!get_oid("HEAD", &curr_head)) {
1023                 write_state_text(state, "abort-safety", oid_to_hex(&curr_head));
1024                 if (!state->rebasing)
1025                         update_ref("am", "ORIG_HEAD", &curr_head, NULL, 0,
1026                                    UPDATE_REFS_DIE_ON_ERR);
1027         } else {
1028                 write_state_text(state, "abort-safety", "");
1029                 if (!state->rebasing)
1030                         delete_ref(NULL, "ORIG_HEAD", NULL, 0);
1031         }
1032
1033         /*
1034          * NOTE: Since the "next" and "last" files determine if an am_state
1035          * session is in progress, they should be written last.
1036          */
1037
1038         write_state_count(state, "next", state->cur);
1039         write_state_count(state, "last", state->last);
1040
1041         strbuf_release(&sb);
1042 }
1043
1044 /**
1045  * Increments the patch pointer, and cleans am_state for the application of the
1046  * next patch.
1047  */
1048 static void am_next(struct am_state *state)
1049 {
1050         struct object_id head;
1051
1052         FREE_AND_NULL(state->author_name);
1053         FREE_AND_NULL(state->author_email);
1054         FREE_AND_NULL(state->author_date);
1055         FREE_AND_NULL(state->msg);
1056         state->msg_len = 0;
1057
1058         unlink(am_path(state, "author-script"));
1059         unlink(am_path(state, "final-commit"));
1060
1061         oidclr(&state->orig_commit);
1062         unlink(am_path(state, "original-commit"));
1063         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
1064
1065         if (!get_oid("HEAD", &head))
1066                 write_state_text(state, "abort-safety", oid_to_hex(&head));
1067         else
1068                 write_state_text(state, "abort-safety", "");
1069
1070         state->cur++;
1071         write_state_count(state, "next", state->cur);
1072 }
1073
1074 /**
1075  * Returns the filename of the current patch email.
1076  */
1077 static const char *msgnum(const struct am_state *state)
1078 {
1079         static struct strbuf sb = STRBUF_INIT;
1080
1081         strbuf_reset(&sb);
1082         strbuf_addf(&sb, "%0*d", state->prec, state->cur);
1083
1084         return sb.buf;
1085 }
1086
1087 /**
1088  * Refresh and write index.
1089  */
1090 static void refresh_and_write_cache(void)
1091 {
1092         struct lock_file lock_file = LOCK_INIT;
1093
1094         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
1095         refresh_cache(REFRESH_QUIET);
1096         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
1097                 die(_("unable to write index file"));
1098 }
1099
1100 /**
1101  * Dies with a user-friendly message on how to proceed after resolving the
1102  * problem. This message can be overridden with state->resolvemsg.
1103  */
1104 static void NORETURN die_user_resolve(const struct am_state *state)
1105 {
1106         if (state->resolvemsg) {
1107                 printf_ln("%s", state->resolvemsg);
1108         } else {
1109                 const char *cmdline = state->interactive ? "git am -i" : "git am";
1110
1111                 printf_ln(_("When you have resolved this problem, run \"%s --continue\"."), cmdline);
1112                 printf_ln(_("If you prefer to skip this patch, run \"%s --skip\" instead."), cmdline);
1113                 printf_ln(_("To restore the original branch and stop patching, run \"%s --abort\"."), cmdline);
1114         }
1115
1116         exit(128);
1117 }
1118
1119 /**
1120  * Appends signoff to the "msg" field of the am_state.
1121  */
1122 static void am_append_signoff(struct am_state *state)
1123 {
1124         struct strbuf sb = STRBUF_INIT;
1125
1126         strbuf_attach(&sb, state->msg, state->msg_len, state->msg_len);
1127         append_signoff(&sb, 0, 0);
1128         state->msg = strbuf_detach(&sb, &state->msg_len);
1129 }
1130
1131 /**
1132  * Parses `mail` using git-mailinfo, extracting its patch and authorship info.
1133  * state->msg will be set to the patch message. state->author_name,
1134  * state->author_email and state->author_date will be set to the patch author's
1135  * name, email and date respectively. The patch body will be written to the
1136  * state directory's "patch" file.
1137  *
1138  * Returns 1 if the patch should be skipped, 0 otherwise.
1139  */
1140 static int parse_mail(struct am_state *state, const char *mail)
1141 {
1142         FILE *fp;
1143         struct strbuf sb = STRBUF_INIT;
1144         struct strbuf msg = STRBUF_INIT;
1145         struct strbuf author_name = STRBUF_INIT;
1146         struct strbuf author_date = STRBUF_INIT;
1147         struct strbuf author_email = STRBUF_INIT;
1148         int ret = 0;
1149         struct mailinfo mi;
1150
1151         setup_mailinfo(&mi);
1152
1153         if (state->utf8)
1154                 mi.metainfo_charset = get_commit_output_encoding();
1155         else
1156                 mi.metainfo_charset = NULL;
1157
1158         switch (state->keep) {
1159         case KEEP_FALSE:
1160                 break;
1161         case KEEP_TRUE:
1162                 mi.keep_subject = 1;
1163                 break;
1164         case KEEP_NON_PATCH:
1165                 mi.keep_non_patch_brackets_in_subject = 1;
1166                 break;
1167         default:
1168                 BUG("invalid value for state->keep");
1169         }
1170
1171         if (state->message_id)
1172                 mi.add_message_id = 1;
1173
1174         switch (state->scissors) {
1175         case SCISSORS_UNSET:
1176                 break;
1177         case SCISSORS_FALSE:
1178                 mi.use_scissors = 0;
1179                 break;
1180         case SCISSORS_TRUE:
1181                 mi.use_scissors = 1;
1182                 break;
1183         default:
1184                 BUG("invalid value for state->scissors");
1185         }
1186
1187         mi.input = xfopen(mail, "r");
1188         mi.output = xfopen(am_path(state, "info"), "w");
1189         if (mailinfo(&mi, am_path(state, "msg"), am_path(state, "patch")))
1190                 die("could not parse patch");
1191
1192         fclose(mi.input);
1193         fclose(mi.output);
1194
1195         if (mi.format_flowed)
1196                 warning(_("Patch sent with format=flowed; "
1197                           "space at the end of lines might be lost."));
1198
1199         /* Extract message and author information */
1200         fp = xfopen(am_path(state, "info"), "r");
1201         while (!strbuf_getline_lf(&sb, fp)) {
1202                 const char *x;
1203
1204                 if (skip_prefix(sb.buf, "Subject: ", &x)) {
1205                         if (msg.len)
1206                                 strbuf_addch(&msg, '\n');
1207                         strbuf_addstr(&msg, x);
1208                 } else if (skip_prefix(sb.buf, "Author: ", &x))
1209                         strbuf_addstr(&author_name, x);
1210                 else if (skip_prefix(sb.buf, "Email: ", &x))
1211                         strbuf_addstr(&author_email, x);
1212                 else if (skip_prefix(sb.buf, "Date: ", &x))
1213                         strbuf_addstr(&author_date, x);
1214         }
1215         fclose(fp);
1216
1217         /* Skip pine's internal folder data */
1218         if (!strcmp(author_name.buf, "Mail System Internal Data")) {
1219                 ret = 1;
1220                 goto finish;
1221         }
1222
1223         if (is_empty_file(am_path(state, "patch"))) {
1224                 printf_ln(_("Patch is empty."));
1225                 die_user_resolve(state);
1226         }
1227
1228         strbuf_addstr(&msg, "\n\n");
1229         strbuf_addbuf(&msg, &mi.log_message);
1230         strbuf_stripspace(&msg, 0);
1231
1232         assert(!state->author_name);
1233         state->author_name = strbuf_detach(&author_name, NULL);
1234
1235         assert(!state->author_email);
1236         state->author_email = strbuf_detach(&author_email, NULL);
1237
1238         assert(!state->author_date);
1239         state->author_date = strbuf_detach(&author_date, NULL);
1240
1241         assert(!state->msg);
1242         state->msg = strbuf_detach(&msg, &state->msg_len);
1243
1244 finish:
1245         strbuf_release(&msg);
1246         strbuf_release(&author_date);
1247         strbuf_release(&author_email);
1248         strbuf_release(&author_name);
1249         strbuf_release(&sb);
1250         clear_mailinfo(&mi);
1251         return ret;
1252 }
1253
1254 /**
1255  * Sets commit_id to the commit hash where the mail was generated from.
1256  * Returns 0 on success, -1 on failure.
1257  */
1258 static int get_mail_commit_oid(struct object_id *commit_id, const char *mail)
1259 {
1260         struct strbuf sb = STRBUF_INIT;
1261         FILE *fp = xfopen(mail, "r");
1262         const char *x;
1263         int ret = 0;
1264
1265         if (strbuf_getline_lf(&sb, fp) ||
1266             !skip_prefix(sb.buf, "From ", &x) ||
1267             get_oid_hex(x, commit_id) < 0)
1268                 ret = -1;
1269
1270         strbuf_release(&sb);
1271         fclose(fp);
1272         return ret;
1273 }
1274
1275 /**
1276  * Sets state->msg, state->author_name, state->author_email, state->author_date
1277  * to the commit's respective info.
1278  */
1279 static void get_commit_info(struct am_state *state, struct commit *commit)
1280 {
1281         const char *buffer, *ident_line, *msg;
1282         size_t ident_len;
1283         struct ident_split id;
1284
1285         buffer = logmsg_reencode(commit, NULL, get_commit_output_encoding());
1286
1287         ident_line = find_commit_header(buffer, "author", &ident_len);
1288
1289         if (split_ident_line(&id, ident_line, ident_len) < 0)
1290                 die(_("invalid ident line: %.*s"), (int)ident_len, ident_line);
1291
1292         assert(!state->author_name);
1293         if (id.name_begin)
1294                 state->author_name =
1295                         xmemdupz(id.name_begin, id.name_end - id.name_begin);
1296         else
1297                 state->author_name = xstrdup("");
1298
1299         assert(!state->author_email);
1300         if (id.mail_begin)
1301                 state->author_email =
1302                         xmemdupz(id.mail_begin, id.mail_end - id.mail_begin);
1303         else
1304                 state->author_email = xstrdup("");
1305
1306         assert(!state->author_date);
1307         state->author_date = xstrdup(show_ident_date(&id, DATE_MODE(NORMAL)));
1308
1309         assert(!state->msg);
1310         msg = strstr(buffer, "\n\n");
1311         if (!msg)
1312                 die(_("unable to parse commit %s"), oid_to_hex(&commit->object.oid));
1313         state->msg = xstrdup(msg + 2);
1314         state->msg_len = strlen(state->msg);
1315         unuse_commit_buffer(commit, buffer);
1316 }
1317
1318 /**
1319  * Writes `commit` as a patch to the state directory's "patch" file.
1320  */
1321 static void write_commit_patch(const struct am_state *state, struct commit *commit)
1322 {
1323         struct rev_info rev_info;
1324         FILE *fp;
1325
1326         fp = xfopen(am_path(state, "patch"), "w");
1327         repo_init_revisions(the_repository, &rev_info, NULL);
1328         rev_info.diff = 1;
1329         rev_info.abbrev = 0;
1330         rev_info.disable_stdin = 1;
1331         rev_info.show_root_diff = 1;
1332         rev_info.diffopt.output_format = DIFF_FORMAT_PATCH;
1333         rev_info.no_commit_id = 1;
1334         rev_info.diffopt.flags.binary = 1;
1335         rev_info.diffopt.flags.full_index = 1;
1336         rev_info.diffopt.use_color = 0;
1337         rev_info.diffopt.file = fp;
1338         rev_info.diffopt.close_file = 1;
1339         add_pending_object(&rev_info, &commit->object, "");
1340         diff_setup_done(&rev_info.diffopt);
1341         log_tree_commit(&rev_info, commit);
1342 }
1343
1344 /**
1345  * Writes the diff of the index against HEAD as a patch to the state
1346  * directory's "patch" file.
1347  */
1348 static void write_index_patch(const struct am_state *state)
1349 {
1350         struct tree *tree;
1351         struct object_id head;
1352         struct rev_info rev_info;
1353         FILE *fp;
1354
1355         if (!get_oid_tree("HEAD", &head))
1356                 tree = lookup_tree(the_repository, &head);
1357         else
1358                 tree = lookup_tree(the_repository,
1359                                    the_repository->hash_algo->empty_tree);
1360
1361         fp = xfopen(am_path(state, "patch"), "w");
1362         repo_init_revisions(the_repository, &rev_info, NULL);
1363         rev_info.diff = 1;
1364         rev_info.disable_stdin = 1;
1365         rev_info.no_commit_id = 1;
1366         rev_info.diffopt.output_format = DIFF_FORMAT_PATCH;
1367         rev_info.diffopt.use_color = 0;
1368         rev_info.diffopt.file = fp;
1369         rev_info.diffopt.close_file = 1;
1370         add_pending_object(&rev_info, &tree->object, "");
1371         diff_setup_done(&rev_info.diffopt);
1372         run_diff_index(&rev_info, 1);
1373 }
1374
1375 /**
1376  * Like parse_mail(), but parses the mail by looking up its commit ID
1377  * directly. This is used in --rebasing mode to bypass git-mailinfo's munging
1378  * of patches.
1379  *
1380  * state->orig_commit will be set to the original commit ID.
1381  *
1382  * Will always return 0 as the patch should never be skipped.
1383  */
1384 static int parse_mail_rebase(struct am_state *state, const char *mail)
1385 {
1386         struct commit *commit;
1387         struct object_id commit_oid;
1388
1389         if (get_mail_commit_oid(&commit_oid, mail) < 0)
1390                 die(_("could not parse %s"), mail);
1391
1392         commit = lookup_commit_or_die(&commit_oid, mail);
1393
1394         get_commit_info(state, commit);
1395
1396         write_commit_patch(state, commit);
1397
1398         oidcpy(&state->orig_commit, &commit_oid);
1399         write_state_text(state, "original-commit", oid_to_hex(&commit_oid));
1400         update_ref("am", "REBASE_HEAD", &commit_oid,
1401                    NULL, REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
1402
1403         return 0;
1404 }
1405
1406 /**
1407  * Applies current patch with git-apply. Returns 0 on success, -1 otherwise. If
1408  * `index_file` is not NULL, the patch will be applied to that index.
1409  */
1410 static int run_apply(const struct am_state *state, const char *index_file)
1411 {
1412         struct argv_array apply_paths = ARGV_ARRAY_INIT;
1413         struct argv_array apply_opts = ARGV_ARRAY_INIT;
1414         struct apply_state apply_state;
1415         int res, opts_left;
1416         int force_apply = 0;
1417         int options = 0;
1418
1419         if (init_apply_state(&apply_state, the_repository, NULL))
1420                 BUG("init_apply_state() failed");
1421
1422         argv_array_push(&apply_opts, "apply");
1423         argv_array_pushv(&apply_opts, state->git_apply_opts.argv);
1424
1425         opts_left = apply_parse_options(apply_opts.argc, apply_opts.argv,
1426                                         &apply_state, &force_apply, &options,
1427                                         NULL);
1428
1429         if (opts_left != 0)
1430                 die("unknown option passed through to git apply");
1431
1432         if (index_file) {
1433                 apply_state.index_file = index_file;
1434                 apply_state.cached = 1;
1435         } else
1436                 apply_state.check_index = 1;
1437
1438         /*
1439          * If we are allowed to fall back on 3-way merge, don't give false
1440          * errors during the initial attempt.
1441          */
1442         if (state->threeway && !index_file)
1443                 apply_state.apply_verbosity = verbosity_silent;
1444
1445         if (check_apply_state(&apply_state, force_apply))
1446                 BUG("check_apply_state() failed");
1447
1448         argv_array_push(&apply_paths, am_path(state, "patch"));
1449
1450         res = apply_all_patches(&apply_state, apply_paths.argc, apply_paths.argv, options);
1451
1452         argv_array_clear(&apply_paths);
1453         argv_array_clear(&apply_opts);
1454         clear_apply_state(&apply_state);
1455
1456         if (res)
1457                 return res;
1458
1459         if (index_file) {
1460                 /* Reload index as apply_all_patches() will have modified it. */
1461                 discard_cache();
1462                 read_cache_from(index_file);
1463         }
1464
1465         return 0;
1466 }
1467
1468 /**
1469  * Builds an index that contains just the blobs needed for a 3way merge.
1470  */
1471 static int build_fake_ancestor(const struct am_state *state, const char *index_file)
1472 {
1473         struct child_process cp = CHILD_PROCESS_INIT;
1474
1475         cp.git_cmd = 1;
1476         argv_array_push(&cp.args, "apply");
1477         argv_array_pushv(&cp.args, state->git_apply_opts.argv);
1478         argv_array_pushf(&cp.args, "--build-fake-ancestor=%s", index_file);
1479         argv_array_push(&cp.args, am_path(state, "patch"));
1480
1481         if (run_command(&cp))
1482                 return -1;
1483
1484         return 0;
1485 }
1486
1487 /**
1488  * Attempt a threeway merge, using index_path as the temporary index.
1489  */
1490 static int fall_back_threeway(const struct am_state *state, const char *index_path)
1491 {
1492         struct object_id orig_tree, their_tree, our_tree;
1493         const struct object_id *bases[1] = { &orig_tree };
1494         struct merge_options o;
1495         struct commit *result;
1496         char *their_tree_name;
1497
1498         if (get_oid("HEAD", &our_tree) < 0)
1499                 oidcpy(&our_tree, the_hash_algo->empty_tree);
1500
1501         if (build_fake_ancestor(state, index_path))
1502                 return error("could not build fake ancestor");
1503
1504         discard_cache();
1505         read_cache_from(index_path);
1506
1507         if (write_index_as_tree(&orig_tree, &the_index, index_path, 0, NULL))
1508                 return error(_("Repository lacks necessary blobs to fall back on 3-way merge."));
1509
1510         say(state, stdout, _("Using index info to reconstruct a base tree..."));
1511
1512         if (!state->quiet) {
1513                 /*
1514                  * List paths that needed 3-way fallback, so that the user can
1515                  * review them with extra care to spot mismerges.
1516                  */
1517                 struct rev_info rev_info;
1518                 const char *diff_filter_str = "--diff-filter=AM";
1519
1520                 repo_init_revisions(the_repository, &rev_info, NULL);
1521                 rev_info.diffopt.output_format = DIFF_FORMAT_NAME_STATUS;
1522                 diff_opt_parse(&rev_info.diffopt, &diff_filter_str, 1, rev_info.prefix);
1523                 add_pending_oid(&rev_info, "HEAD", &our_tree, 0);
1524                 diff_setup_done(&rev_info.diffopt);
1525                 run_diff_index(&rev_info, 1);
1526         }
1527
1528         if (run_apply(state, index_path))
1529                 return error(_("Did you hand edit your patch?\n"
1530                                 "It does not apply to blobs recorded in its index."));
1531
1532         if (write_index_as_tree(&their_tree, &the_index, index_path, 0, NULL))
1533                 return error("could not write tree");
1534
1535         say(state, stdout, _("Falling back to patching base and 3-way merge..."));
1536
1537         discard_cache();
1538         read_cache();
1539
1540         /*
1541          * This is not so wrong. Depending on which base we picked, orig_tree
1542          * may be wildly different from ours, but their_tree has the same set of
1543          * wildly different changes in parts the patch did not touch, so
1544          * recursive ends up canceling them, saying that we reverted all those
1545          * changes.
1546          */
1547
1548         init_merge_options(&o);
1549
1550         o.branch1 = "HEAD";
1551         their_tree_name = xstrfmt("%.*s", linelen(state->msg), state->msg);
1552         o.branch2 = their_tree_name;
1553         o.detect_directory_renames = 0;
1554
1555         if (state->quiet)
1556                 o.verbosity = 0;
1557
1558         if (merge_recursive_generic(&o, &our_tree, &their_tree, 1, bases, &result)) {
1559                 repo_rerere(the_repository, state->allow_rerere_autoupdate);
1560                 free(their_tree_name);
1561                 return error(_("Failed to merge in the changes."));
1562         }
1563
1564         free(their_tree_name);
1565         return 0;
1566 }
1567
1568 /**
1569  * Commits the current index with state->msg as the commit message and
1570  * state->author_name, state->author_email and state->author_date as the author
1571  * information.
1572  */
1573 static void do_commit(const struct am_state *state)
1574 {
1575         struct object_id tree, parent, commit;
1576         const struct object_id *old_oid;
1577         struct commit_list *parents = NULL;
1578         const char *reflog_msg, *author;
1579         struct strbuf sb = STRBUF_INIT;
1580
1581         if (run_hook_le(NULL, "pre-applypatch", NULL))
1582                 exit(1);
1583
1584         if (write_cache_as_tree(&tree, 0, NULL))
1585                 die(_("git write-tree failed to write a tree"));
1586
1587         if (!get_oid_commit("HEAD", &parent)) {
1588                 old_oid = &parent;
1589                 commit_list_insert(lookup_commit(the_repository, &parent),
1590                                    &parents);
1591         } else {
1592                 old_oid = NULL;
1593                 say(state, stderr, _("applying to an empty history"));
1594         }
1595
1596         author = fmt_ident(state->author_name, state->author_email,
1597                         state->ignore_date ? NULL : state->author_date,
1598                         IDENT_STRICT);
1599
1600         if (state->committer_date_is_author_date)
1601                 setenv("GIT_COMMITTER_DATE",
1602                         state->ignore_date ? "" : state->author_date, 1);
1603
1604         if (commit_tree(state->msg, state->msg_len, &tree, parents, &commit,
1605                         author, state->sign_commit))
1606                 die(_("failed to write commit object"));
1607
1608         reflog_msg = getenv("GIT_REFLOG_ACTION");
1609         if (!reflog_msg)
1610                 reflog_msg = "am";
1611
1612         strbuf_addf(&sb, "%s: %.*s", reflog_msg, linelen(state->msg),
1613                         state->msg);
1614
1615         update_ref(sb.buf, "HEAD", &commit, old_oid, 0,
1616                    UPDATE_REFS_DIE_ON_ERR);
1617
1618         if (state->rebasing) {
1619                 FILE *fp = xfopen(am_path(state, "rewritten"), "a");
1620
1621                 assert(!is_null_oid(&state->orig_commit));
1622                 fprintf(fp, "%s ", oid_to_hex(&state->orig_commit));
1623                 fprintf(fp, "%s\n", oid_to_hex(&commit));
1624                 fclose(fp);
1625         }
1626
1627         run_hook_le(NULL, "post-applypatch", NULL);
1628
1629         strbuf_release(&sb);
1630 }
1631
1632 /**
1633  * Validates the am_state for resuming -- the "msg" and authorship fields must
1634  * be filled up.
1635  */
1636 static void validate_resume_state(const struct am_state *state)
1637 {
1638         if (!state->msg)
1639                 die(_("cannot resume: %s does not exist."),
1640                         am_path(state, "final-commit"));
1641
1642         if (!state->author_name || !state->author_email || !state->author_date)
1643                 die(_("cannot resume: %s does not exist."),
1644                         am_path(state, "author-script"));
1645 }
1646
1647 /**
1648  * Interactively prompt the user on whether the current patch should be
1649  * applied.
1650  *
1651  * Returns 0 if the user chooses to apply the patch, 1 if the user chooses to
1652  * skip it.
1653  */
1654 static int do_interactive(struct am_state *state)
1655 {
1656         assert(state->msg);
1657
1658         if (!isatty(0))
1659                 die(_("cannot be interactive without stdin connected to a terminal."));
1660
1661         for (;;) {
1662                 const char *reply;
1663
1664                 puts(_("Commit Body is:"));
1665                 puts("--------------------------");
1666                 printf("%s", state->msg);
1667                 puts("--------------------------");
1668
1669                 /*
1670                  * TRANSLATORS: Make sure to include [y], [n], [e], [v] and [a]
1671                  * in your translation. The program will only accept English
1672                  * input at this point.
1673                  */
1674                 reply = git_prompt(_("Apply? [y]es/[n]o/[e]dit/[v]iew patch/[a]ccept all: "), PROMPT_ECHO);
1675
1676                 if (!reply) {
1677                         continue;
1678                 } else if (*reply == 'y' || *reply == 'Y') {
1679                         return 0;
1680                 } else if (*reply == 'a' || *reply == 'A') {
1681                         state->interactive = 0;
1682                         return 0;
1683                 } else if (*reply == 'n' || *reply == 'N') {
1684                         return 1;
1685                 } else if (*reply == 'e' || *reply == 'E') {
1686                         struct strbuf msg = STRBUF_INIT;
1687
1688                         if (!launch_editor(am_path(state, "final-commit"), &msg, NULL)) {
1689                                 free(state->msg);
1690                                 state->msg = strbuf_detach(&msg, &state->msg_len);
1691                         }
1692                         strbuf_release(&msg);
1693                 } else if (*reply == 'v' || *reply == 'V') {
1694                         const char *pager = git_pager(1);
1695                         struct child_process cp = CHILD_PROCESS_INIT;
1696
1697                         if (!pager)
1698                                 pager = "cat";
1699                         prepare_pager_args(&cp, pager);
1700                         argv_array_push(&cp.args, am_path(state, "patch"));
1701                         run_command(&cp);
1702                 }
1703         }
1704 }
1705
1706 /**
1707  * Applies all queued mail.
1708  *
1709  * If `resume` is true, we are "resuming". The "msg" and authorship fields, as
1710  * well as the state directory's "patch" file is used as-is for applying the
1711  * patch and committing it.
1712  */
1713 static void am_run(struct am_state *state, int resume)
1714 {
1715         const char *argv_gc_auto[] = {"gc", "--auto", NULL};
1716         struct strbuf sb = STRBUF_INIT;
1717
1718         unlink(am_path(state, "dirtyindex"));
1719
1720         refresh_and_write_cache();
1721
1722         if (index_has_changes(&the_index, NULL, &sb)) {
1723                 write_state_bool(state, "dirtyindex", 1);
1724                 die(_("Dirty index: cannot apply patches (dirty: %s)"), sb.buf);
1725         }
1726
1727         strbuf_release(&sb);
1728
1729         while (state->cur <= state->last) {
1730                 const char *mail = am_path(state, msgnum(state));
1731                 int apply_status;
1732
1733                 reset_ident_date();
1734
1735                 if (!file_exists(mail))
1736                         goto next;
1737
1738                 if (resume) {
1739                         validate_resume_state(state);
1740                 } else {
1741                         int skip;
1742
1743                         if (state->rebasing)
1744                                 skip = parse_mail_rebase(state, mail);
1745                         else
1746                                 skip = parse_mail(state, mail);
1747
1748                         if (skip)
1749                                 goto next; /* mail should be skipped */
1750
1751                         if (state->signoff)
1752                                 am_append_signoff(state);
1753
1754                         write_author_script(state);
1755                         write_commit_msg(state);
1756                 }
1757
1758                 if (state->interactive && do_interactive(state))
1759                         goto next;
1760
1761                 if (run_applypatch_msg_hook(state))
1762                         exit(1);
1763
1764                 say(state, stdout, _("Applying: %.*s"), linelen(state->msg), state->msg);
1765
1766                 apply_status = run_apply(state, NULL);
1767
1768                 if (apply_status && state->threeway) {
1769                         struct strbuf sb = STRBUF_INIT;
1770
1771                         strbuf_addstr(&sb, am_path(state, "patch-merge-index"));
1772                         apply_status = fall_back_threeway(state, sb.buf);
1773                         strbuf_release(&sb);
1774
1775                         /*
1776                          * Applying the patch to an earlier tree and merging
1777                          * the result may have produced the same tree as ours.
1778                          */
1779                         if (!apply_status &&
1780                             !index_has_changes(&the_index, NULL, NULL)) {
1781                                 say(state, stdout, _("No changes -- Patch already applied."));
1782                                 goto next;
1783                         }
1784                 }
1785
1786                 if (apply_status) {
1787                         printf_ln(_("Patch failed at %s %.*s"), msgnum(state),
1788                                 linelen(state->msg), state->msg);
1789
1790                         if (advice_amworkdir)
1791                                 advise(_("Use 'git am --show-current-patch' to see the failed patch"));
1792
1793                         die_user_resolve(state);
1794                 }
1795
1796                 do_commit(state);
1797
1798 next:
1799                 am_next(state);
1800
1801                 if (resume)
1802                         am_load(state);
1803                 resume = 0;
1804         }
1805
1806         if (!is_empty_file(am_path(state, "rewritten"))) {
1807                 assert(state->rebasing);
1808                 copy_notes_for_rebase(state);
1809                 run_post_rewrite_hook(state);
1810         }
1811
1812         /*
1813          * In rebasing mode, it's up to the caller to take care of
1814          * housekeeping.
1815          */
1816         if (!state->rebasing) {
1817                 am_destroy(state);
1818                 close_all_packs(the_repository->objects);
1819                 run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
1820         }
1821 }
1822
1823 /**
1824  * Resume the current am session after patch application failure. The user did
1825  * all the hard work, and we do not have to do any patch application. Just
1826  * trust and commit what the user has in the index and working tree.
1827  */
1828 static void am_resolve(struct am_state *state)
1829 {
1830         validate_resume_state(state);
1831
1832         say(state, stdout, _("Applying: %.*s"), linelen(state->msg), state->msg);
1833
1834         if (!index_has_changes(&the_index, NULL, NULL)) {
1835                 printf_ln(_("No changes - did you forget to use 'git add'?\n"
1836                         "If there is nothing left to stage, chances are that something else\n"
1837                         "already introduced the same changes; you might want to skip this patch."));
1838                 die_user_resolve(state);
1839         }
1840
1841         if (unmerged_cache()) {
1842                 printf_ln(_("You still have unmerged paths in your index.\n"
1843                         "You should 'git add' each file with resolved conflicts to mark them as such.\n"
1844                         "You might run `git rm` on a file to accept \"deleted by them\" for it."));
1845                 die_user_resolve(state);
1846         }
1847
1848         if (state->interactive) {
1849                 write_index_patch(state);
1850                 if (do_interactive(state))
1851                         goto next;
1852         }
1853
1854         repo_rerere(the_repository, 0);
1855
1856         do_commit(state);
1857
1858 next:
1859         am_next(state);
1860         am_load(state);
1861         am_run(state, 0);
1862 }
1863
1864 /**
1865  * Performs a checkout fast-forward from `head` to `remote`. If `reset` is
1866  * true, any unmerged entries will be discarded. Returns 0 on success, -1 on
1867  * failure.
1868  */
1869 static int fast_forward_to(struct tree *head, struct tree *remote, int reset)
1870 {
1871         struct lock_file lock_file = LOCK_INIT;
1872         struct unpack_trees_options opts;
1873         struct tree_desc t[2];
1874
1875         if (parse_tree(head) || parse_tree(remote))
1876                 return -1;
1877
1878         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
1879
1880         refresh_cache(REFRESH_QUIET);
1881
1882         memset(&opts, 0, sizeof(opts));
1883         opts.head_idx = 1;
1884         opts.src_index = &the_index;
1885         opts.dst_index = &the_index;
1886         opts.update = 1;
1887         opts.merge = 1;
1888         opts.reset = reset;
1889         opts.fn = twoway_merge;
1890         init_tree_desc(&t[0], head->buffer, head->size);
1891         init_tree_desc(&t[1], remote->buffer, remote->size);
1892
1893         if (unpack_trees(2, t, &opts)) {
1894                 rollback_lock_file(&lock_file);
1895                 return -1;
1896         }
1897
1898         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
1899                 die(_("unable to write new index file"));
1900
1901         return 0;
1902 }
1903
1904 /**
1905  * Merges a tree into the index. The index's stat info will take precedence
1906  * over the merged tree's. Returns 0 on success, -1 on failure.
1907  */
1908 static int merge_tree(struct tree *tree)
1909 {
1910         struct lock_file lock_file = LOCK_INIT;
1911         struct unpack_trees_options opts;
1912         struct tree_desc t[1];
1913
1914         if (parse_tree(tree))
1915                 return -1;
1916
1917         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
1918
1919         memset(&opts, 0, sizeof(opts));
1920         opts.head_idx = 1;
1921         opts.src_index = &the_index;
1922         opts.dst_index = &the_index;
1923         opts.merge = 1;
1924         opts.fn = oneway_merge;
1925         init_tree_desc(&t[0], tree->buffer, tree->size);
1926
1927         if (unpack_trees(1, t, &opts)) {
1928                 rollback_lock_file(&lock_file);
1929                 return -1;
1930         }
1931
1932         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
1933                 die(_("unable to write new index file"));
1934
1935         return 0;
1936 }
1937
1938 /**
1939  * Clean the index without touching entries that are not modified between
1940  * `head` and `remote`.
1941  */
1942 static int clean_index(const struct object_id *head, const struct object_id *remote)
1943 {
1944         struct tree *head_tree, *remote_tree, *index_tree;
1945         struct object_id index;
1946
1947         head_tree = parse_tree_indirect(head);
1948         if (!head_tree)
1949                 return error(_("Could not parse object '%s'."), oid_to_hex(head));
1950
1951         remote_tree = parse_tree_indirect(remote);
1952         if (!remote_tree)
1953                 return error(_("Could not parse object '%s'."), oid_to_hex(remote));
1954
1955         read_cache_unmerged();
1956
1957         if (fast_forward_to(head_tree, head_tree, 1))
1958                 return -1;
1959
1960         if (write_cache_as_tree(&index, 0, NULL))
1961                 return -1;
1962
1963         index_tree = parse_tree_indirect(&index);
1964         if (!index_tree)
1965                 return error(_("Could not parse object '%s'."), oid_to_hex(&index));
1966
1967         if (fast_forward_to(index_tree, remote_tree, 0))
1968                 return -1;
1969
1970         if (merge_tree(remote_tree))
1971                 return -1;
1972
1973         remove_branch_state();
1974
1975         return 0;
1976 }
1977
1978 /**
1979  * Resets rerere's merge resolution metadata.
1980  */
1981 static void am_rerere_clear(void)
1982 {
1983         struct string_list merge_rr = STRING_LIST_INIT_DUP;
1984         rerere_clear(&merge_rr);
1985         string_list_clear(&merge_rr, 1);
1986 }
1987
1988 /**
1989  * Resume the current am session by skipping the current patch.
1990  */
1991 static void am_skip(struct am_state *state)
1992 {
1993         struct object_id head;
1994
1995         am_rerere_clear();
1996
1997         if (get_oid("HEAD", &head))
1998                 oidcpy(&head, the_hash_algo->empty_tree);
1999
2000         if (clean_index(&head, &head))
2001                 die(_("failed to clean index"));
2002
2003         am_next(state);
2004         am_load(state);
2005         am_run(state, 0);
2006 }
2007
2008 /**
2009  * Returns true if it is safe to reset HEAD to the ORIG_HEAD, false otherwise.
2010  *
2011  * It is not safe to reset HEAD when:
2012  * 1. git-am previously failed because the index was dirty.
2013  * 2. HEAD has moved since git-am previously failed.
2014  */
2015 static int safe_to_abort(const struct am_state *state)
2016 {
2017         struct strbuf sb = STRBUF_INIT;
2018         struct object_id abort_safety, head;
2019
2020         if (file_exists(am_path(state, "dirtyindex")))
2021                 return 0;
2022
2023         if (read_state_file(&sb, state, "abort-safety", 1) > 0) {
2024                 if (get_oid_hex(sb.buf, &abort_safety))
2025                         die(_("could not parse %s"), am_path(state, "abort-safety"));
2026         } else
2027                 oidclr(&abort_safety);
2028         strbuf_release(&sb);
2029
2030         if (get_oid("HEAD", &head))
2031                 oidclr(&head);
2032
2033         if (oideq(&head, &abort_safety))
2034                 return 1;
2035
2036         warning(_("You seem to have moved HEAD since the last 'am' failure.\n"
2037                 "Not rewinding to ORIG_HEAD"));
2038
2039         return 0;
2040 }
2041
2042 /**
2043  * Aborts the current am session if it is safe to do so.
2044  */
2045 static void am_abort(struct am_state *state)
2046 {
2047         struct object_id curr_head, orig_head;
2048         int has_curr_head, has_orig_head;
2049         char *curr_branch;
2050
2051         if (!safe_to_abort(state)) {
2052                 am_destroy(state);
2053                 return;
2054         }
2055
2056         am_rerere_clear();
2057
2058         curr_branch = resolve_refdup("HEAD", 0, &curr_head, NULL);
2059         has_curr_head = curr_branch && !is_null_oid(&curr_head);
2060         if (!has_curr_head)
2061                 oidcpy(&curr_head, the_hash_algo->empty_tree);
2062
2063         has_orig_head = !get_oid("ORIG_HEAD", &orig_head);
2064         if (!has_orig_head)
2065                 oidcpy(&orig_head, the_hash_algo->empty_tree);
2066
2067         clean_index(&curr_head, &orig_head);
2068
2069         if (has_orig_head)
2070                 update_ref("am --abort", "HEAD", &orig_head,
2071                            has_curr_head ? &curr_head : NULL, 0,
2072                            UPDATE_REFS_DIE_ON_ERR);
2073         else if (curr_branch)
2074                 delete_ref(NULL, curr_branch, NULL, REF_NO_DEREF);
2075
2076         free(curr_branch);
2077         am_destroy(state);
2078 }
2079
2080 static int show_patch(struct am_state *state)
2081 {
2082         struct strbuf sb = STRBUF_INIT;
2083         const char *patch_path;
2084         int len;
2085
2086         if (!is_null_oid(&state->orig_commit)) {
2087                 const char *av[4] = { "show", NULL, "--", NULL };
2088                 char *new_oid_str;
2089                 int ret;
2090
2091                 av[1] = new_oid_str = xstrdup(oid_to_hex(&state->orig_commit));
2092                 ret = run_command_v_opt(av, RUN_GIT_CMD);
2093                 free(new_oid_str);
2094                 return ret;
2095         }
2096
2097         patch_path = am_path(state, msgnum(state));
2098         len = strbuf_read_file(&sb, patch_path, 0);
2099         if (len < 0)
2100                 die_errno(_("failed to read '%s'"), patch_path);
2101
2102         setup_pager();
2103         write_in_full(1, sb.buf, sb.len);
2104         strbuf_release(&sb);
2105         return 0;
2106 }
2107
2108 /**
2109  * parse_options() callback that validates and sets opt->value to the
2110  * PATCH_FORMAT_* enum value corresponding to `arg`.
2111  */
2112 static int parse_opt_patchformat(const struct option *opt, const char *arg, int unset)
2113 {
2114         int *opt_value = opt->value;
2115
2116         if (unset)
2117                 *opt_value = PATCH_FORMAT_UNKNOWN;
2118         else if (!strcmp(arg, "mbox"))
2119                 *opt_value = PATCH_FORMAT_MBOX;
2120         else if (!strcmp(arg, "stgit"))
2121                 *opt_value = PATCH_FORMAT_STGIT;
2122         else if (!strcmp(arg, "stgit-series"))
2123                 *opt_value = PATCH_FORMAT_STGIT_SERIES;
2124         else if (!strcmp(arg, "hg"))
2125                 *opt_value = PATCH_FORMAT_HG;
2126         else if (!strcmp(arg, "mboxrd"))
2127                 *opt_value = PATCH_FORMAT_MBOXRD;
2128         else
2129                 return error(_("Invalid value for --patch-format: %s"), arg);
2130         return 0;
2131 }
2132
2133 enum resume_mode {
2134         RESUME_FALSE = 0,
2135         RESUME_APPLY,
2136         RESUME_RESOLVED,
2137         RESUME_SKIP,
2138         RESUME_ABORT,
2139         RESUME_QUIT,
2140         RESUME_SHOW_PATCH
2141 };
2142
2143 static int git_am_config(const char *k, const char *v, void *cb)
2144 {
2145         int status;
2146
2147         status = git_gpg_config(k, v, NULL);
2148         if (status)
2149                 return status;
2150
2151         return git_default_config(k, v, NULL);
2152 }
2153
2154 int cmd_am(int argc, const char **argv, const char *prefix)
2155 {
2156         struct am_state state;
2157         int binary = -1;
2158         int keep_cr = -1;
2159         int patch_format = PATCH_FORMAT_UNKNOWN;
2160         enum resume_mode resume = RESUME_FALSE;
2161         int in_progress;
2162         int ret = 0;
2163
2164         const char * const usage[] = {
2165                 N_("git am [<options>] [(<mbox> | <Maildir>)...]"),
2166                 N_("git am [<options>] (--continue | --skip | --abort)"),
2167                 NULL
2168         };
2169
2170         struct option options[] = {
2171                 OPT_BOOL('i', "interactive", &state.interactive,
2172                         N_("run interactively")),
2173                 OPT_HIDDEN_BOOL('b', "binary", &binary,
2174                         N_("historical option -- no-op")),
2175                 OPT_BOOL('3', "3way", &state.threeway,
2176                         N_("allow fall back on 3way merging if needed")),
2177                 OPT__QUIET(&state.quiet, N_("be quiet")),
2178                 OPT_SET_INT('s', "signoff", &state.signoff,
2179                         N_("add a Signed-off-by line to the commit message"),
2180                         SIGNOFF_EXPLICIT),
2181                 OPT_BOOL('u', "utf8", &state.utf8,
2182                         N_("recode into utf8 (default)")),
2183                 OPT_SET_INT('k', "keep", &state.keep,
2184                         N_("pass -k flag to git-mailinfo"), KEEP_TRUE),
2185                 OPT_SET_INT(0, "keep-non-patch", &state.keep,
2186                         N_("pass -b flag to git-mailinfo"), KEEP_NON_PATCH),
2187                 OPT_BOOL('m', "message-id", &state.message_id,
2188                         N_("pass -m flag to git-mailinfo")),
2189                 OPT_SET_INT_F(0, "keep-cr", &keep_cr,
2190                         N_("pass --keep-cr flag to git-mailsplit for mbox format"),
2191                         1, PARSE_OPT_NONEG),
2192                 OPT_SET_INT_F(0, "no-keep-cr", &keep_cr,
2193                         N_("do not pass --keep-cr flag to git-mailsplit independent of am.keepcr"),
2194                         0, PARSE_OPT_NONEG),
2195                 OPT_BOOL('c', "scissors", &state.scissors,
2196                         N_("strip everything before a scissors line")),
2197                 OPT_PASSTHRU_ARGV(0, "whitespace", &state.git_apply_opts, N_("action"),
2198                         N_("pass it through git-apply"),
2199                         0),
2200                 OPT_PASSTHRU_ARGV(0, "ignore-space-change", &state.git_apply_opts, NULL,
2201                         N_("pass it through git-apply"),
2202                         PARSE_OPT_NOARG),
2203                 OPT_PASSTHRU_ARGV(0, "ignore-whitespace", &state.git_apply_opts, NULL,
2204                         N_("pass it through git-apply"),
2205                         PARSE_OPT_NOARG),
2206                 OPT_PASSTHRU_ARGV(0, "directory", &state.git_apply_opts, N_("root"),
2207                         N_("pass it through git-apply"),
2208                         0),
2209                 OPT_PASSTHRU_ARGV(0, "exclude", &state.git_apply_opts, N_("path"),
2210                         N_("pass it through git-apply"),
2211                         0),
2212                 OPT_PASSTHRU_ARGV(0, "include", &state.git_apply_opts, N_("path"),
2213                         N_("pass it through git-apply"),
2214                         0),
2215                 OPT_PASSTHRU_ARGV('C', NULL, &state.git_apply_opts, N_("n"),
2216                         N_("pass it through git-apply"),
2217                         0),
2218                 OPT_PASSTHRU_ARGV('p', NULL, &state.git_apply_opts, N_("num"),
2219                         N_("pass it through git-apply"),
2220                         0),
2221                 OPT_CALLBACK(0, "patch-format", &patch_format, N_("format"),
2222                         N_("format the patch(es) are in"),
2223                         parse_opt_patchformat),
2224                 OPT_PASSTHRU_ARGV(0, "reject", &state.git_apply_opts, NULL,
2225                         N_("pass it through git-apply"),
2226                         PARSE_OPT_NOARG),
2227                 OPT_STRING(0, "resolvemsg", &state.resolvemsg, NULL,
2228                         N_("override error message when patch failure occurs")),
2229                 OPT_CMDMODE(0, "continue", &resume,
2230                         N_("continue applying patches after resolving a conflict"),
2231                         RESUME_RESOLVED),
2232                 OPT_CMDMODE('r', "resolved", &resume,
2233                         N_("synonyms for --continue"),
2234                         RESUME_RESOLVED),
2235                 OPT_CMDMODE(0, "skip", &resume,
2236                         N_("skip the current patch"),
2237                         RESUME_SKIP),
2238                 OPT_CMDMODE(0, "abort", &resume,
2239                         N_("restore the original branch and abort the patching operation."),
2240                         RESUME_ABORT),
2241                 OPT_CMDMODE(0, "quit", &resume,
2242                         N_("abort the patching operation but keep HEAD where it is."),
2243                         RESUME_QUIT),
2244                 OPT_CMDMODE(0, "show-current-patch", &resume,
2245                         N_("show the patch being applied."),
2246                         RESUME_SHOW_PATCH),
2247                 OPT_BOOL(0, "committer-date-is-author-date",
2248                         &state.committer_date_is_author_date,
2249                         N_("lie about committer date")),
2250                 OPT_BOOL(0, "ignore-date", &state.ignore_date,
2251                         N_("use current timestamp for author date")),
2252                 OPT_RERERE_AUTOUPDATE(&state.allow_rerere_autoupdate),
2253                 { OPTION_STRING, 'S', "gpg-sign", &state.sign_commit, N_("key-id"),
2254                   N_("GPG-sign commits"),
2255                   PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
2256                 OPT_HIDDEN_BOOL(0, "rebasing", &state.rebasing,
2257                         N_("(internal use for git-rebase)")),
2258                 OPT_END()
2259         };
2260
2261         if (argc == 2 && !strcmp(argv[1], "-h"))
2262                 usage_with_options(usage, options);
2263
2264         git_config(git_am_config, NULL);
2265
2266         am_state_init(&state);
2267
2268         in_progress = am_in_progress(&state);
2269         if (in_progress)
2270                 am_load(&state);
2271
2272         argc = parse_options(argc, argv, prefix, options, usage, 0);
2273
2274         if (binary >= 0)
2275                 fprintf_ln(stderr, _("The -b/--binary option has been a no-op for long time, and\n"
2276                                 "it will be removed. Please do not use it anymore."));
2277
2278         /* Ensure a valid committer ident can be constructed */
2279         git_committer_info(IDENT_STRICT);
2280
2281         if (read_index_preload(&the_index, NULL, 0) < 0)
2282                 die(_("failed to read the index"));
2283
2284         if (in_progress) {
2285                 /*
2286                  * Catch user error to feed us patches when there is a session
2287                  * in progress:
2288                  *
2289                  * 1. mbox path(s) are provided on the command-line.
2290                  * 2. stdin is not a tty: the user is trying to feed us a patch
2291                  *    from standard input. This is somewhat unreliable -- stdin
2292                  *    could be /dev/null for example and the caller did not
2293                  *    intend to feed us a patch but wanted to continue
2294                  *    unattended.
2295                  */
2296                 if (argc || (resume == RESUME_FALSE && !isatty(0)))
2297                         die(_("previous rebase directory %s still exists but mbox given."),
2298                                 state.dir);
2299
2300                 if (resume == RESUME_FALSE)
2301                         resume = RESUME_APPLY;
2302
2303                 if (state.signoff == SIGNOFF_EXPLICIT)
2304                         am_append_signoff(&state);
2305         } else {
2306                 struct argv_array paths = ARGV_ARRAY_INIT;
2307                 int i;
2308
2309                 /*
2310                  * Handle stray state directory in the independent-run case. In
2311                  * the --rebasing case, it is up to the caller to take care of
2312                  * stray directories.
2313                  */
2314                 if (file_exists(state.dir) && !state.rebasing) {
2315                         if (resume == RESUME_ABORT || resume == RESUME_QUIT) {
2316                                 am_destroy(&state);
2317                                 am_state_release(&state);
2318                                 return 0;
2319                         }
2320
2321                         die(_("Stray %s directory found.\n"
2322                                 "Use \"git am --abort\" to remove it."),
2323                                 state.dir);
2324                 }
2325
2326                 if (resume)
2327                         die(_("Resolve operation not in progress, we are not resuming."));
2328
2329                 for (i = 0; i < argc; i++) {
2330                         if (is_absolute_path(argv[i]) || !prefix)
2331                                 argv_array_push(&paths, argv[i]);
2332                         else
2333                                 argv_array_push(&paths, mkpath("%s/%s", prefix, argv[i]));
2334                 }
2335
2336                 am_setup(&state, patch_format, paths.argv, keep_cr);
2337
2338                 argv_array_clear(&paths);
2339         }
2340
2341         switch (resume) {
2342         case RESUME_FALSE:
2343                 am_run(&state, 0);
2344                 break;
2345         case RESUME_APPLY:
2346                 am_run(&state, 1);
2347                 break;
2348         case RESUME_RESOLVED:
2349                 am_resolve(&state);
2350                 break;
2351         case RESUME_SKIP:
2352                 am_skip(&state);
2353                 break;
2354         case RESUME_ABORT:
2355                 am_abort(&state);
2356                 break;
2357         case RESUME_QUIT:
2358                 am_rerere_clear();
2359                 am_destroy(&state);
2360                 break;
2361         case RESUME_SHOW_PATCH:
2362                 ret = show_patch(&state);
2363                 break;
2364         default:
2365                 BUG("invalid resume value");
2366         }
2367
2368         am_state_release(&state);
2369
2370         return ret;
2371 }