builtin-commit.c

   1 /*
   2  * Builtin "git commit"
   3  *
   4  * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>
   5  * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
   6  */
   7
   8 #include "cache.h"
   9 #include "cache-tree.h"
  10 #include "dir.h"
  11 #include "builtin.h"
  12 #include "diff.h"
  13 #include "diffcore.h"
  14 #include "commit.h"
  15 #include "revision.h"
  16 #include "wt-status.h"
  17 #include "run-command.h"
  18 #include "refs.h"
  19 #include "log-tree.h"
  20 #include "strbuf.h"
  21 #include "utf8.h"
  22 #include "parse-options.h"
  23 #include "path-list.h"
  24
  25 static const char * const builtin_commit_usage[] = {
  26         "git-commit [options] [--] <filepattern>...",
  27         NULL
  28 };
  29
  30 static unsigned char head_sha1[20], merge_head_sha1[20];
  31 static char *use_message_buffer;
  32 static const char commit_editmsg[] = "COMMIT_EDITMSG";
  33 static struct lock_file index_lock; /* real index */
  34 static struct lock_file false_lock; /* used only for partial commits */
  35 static enum {
  36         COMMIT_AS_IS = 1,
  37         COMMIT_NORMAL,
  38         COMMIT_PARTIAL,
  39 } commit_style;
  40
  41 static char *logfile, *force_author, *template_file;
  42 static char *edit_message, *use_message;
  43 static int all, edit_flag, also, interactive, only, amend, signoff;
  44 static int quiet, verbose, untracked_files, no_verify;
  45
  46 static int no_edit, initial_commit, in_merge;
  47 const char *only_include_assumed;
  48 struct strbuf message;
  49
  50 static int opt_parse_m(const struct option *opt, const char *arg, int unset)
  51 {
  52         struct strbuf *buf = opt->value;
  53         if (unset)
  54                 strbuf_setlen(buf, 0);
  55         else {
  56                 strbuf_addstr(buf, arg);
  57                 strbuf_addch(buf, '\n');
  58                 strbuf_addch(buf, '\n');
  59         }
  60         return 0;
  61 }
  62
  63 static struct option builtin_commit_options[] = {
  64         OPT__QUIET(&quiet),
  65         OPT__VERBOSE(&verbose),
  66         OPT_GROUP("Commit message options"),
  67
  68         OPT_STRING('F', "file", &logfile, "FILE", "read log from file"),
  69         OPT_STRING(0, "author", &force_author, "AUTHOR", "override author for commit"),
  70         OPT_CALLBACK('m', "message", &message, "MESSAGE", "specify commit message", opt_parse_m),
  71         OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit "),
  72         OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
  73         OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by: header"),
  74         OPT_STRING('t', "template", &template_file, "FILE", "use specified template file"),
  75         OPT_BOOLEAN('e', "edit", &edit_flag, "force edit of commit"),
  76
  77         OPT_GROUP("Commit contents options"),
  78         OPT_BOOLEAN('a', "all", &all, "commit all changed files"),
  79         OPT_BOOLEAN('i', "include", &also, "add specified files to index for commit"),
  80         OPT_BOOLEAN(0, "interactive", &interactive, "interactively add files"),
  81         OPT_BOOLEAN('o', "only", &only, ""),
  82         OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
  83         OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
  84         OPT_BOOLEAN(0, "untracked-files", &untracked_files, "show all untracked files"),
  85
  86         OPT_END()
  87 };
  88
  89 static void rollback_index_files(void)
  90 {
  91         switch (commit_style) {
  92         case COMMIT_AS_IS:
  93                 break; /* nothing to do */
  94         case COMMIT_NORMAL:
  95                 rollback_lock_file(&index_lock);
  96                 break;
  97         case COMMIT_PARTIAL:
  98                 rollback_lock_file(&index_lock);
  99                 rollback_lock_file(&false_lock);
 100                 break;
 101         }
 102 }
 103
 104 static void commit_index_files(void)
 105 {
 106         switch (commit_style) {
 107         case COMMIT_AS_IS:
 108                 break; /* nothing to do */
 109         case COMMIT_NORMAL:
 110                 commit_lock_file(&index_lock);
 111                 break;
 112         case COMMIT_PARTIAL:
 113                 commit_lock_file(&index_lock);
 114                 rollback_lock_file(&false_lock);
 115                 break;
 116         }
 117 }
 118
 119 /*
 120  * Take a union of paths in the index and the named tree (typically, "HEAD"),
 121  * and return the paths that match the given pattern in list.
 122  */
 123 static int list_paths(struct path_list *list, const char *with_tree,
 124                       const char *prefix, const char **pattern)
 125 {
 126         int i;
 127         char *m;
 128
 129         for (i = 0; pattern[i]; i++)
 130                 ;
 131         m = xcalloc(1, i);
 132
 133         if (with_tree)
 134                 overlay_tree_on_cache(with_tree, prefix);
 135
 136         for (i = 0; i < active_nr; i++) {
 137                 struct cache_entry *ce = active_cache[i];
 138                 if (ce->ce_flags & htons(CE_UPDATE))
 139                         continue;
 140                 if (!pathspec_match(pattern, m, ce->name, 0))
 141                         continue;
 142                 path_list_insert(ce->name, list);
 143         }
 144
 145         return report_path_error(m, pattern, prefix ? strlen(prefix) : 0);
 146 }
 147
 148 static void add_remove_files(struct path_list *list)
 149 {
 150         int i;
 151         for (i = 0; i < list->nr; i++) {
 152                 struct path_list_item *p = &(list->items[i]);
 153                 if (file_exists(p->path))
 154                         add_file_to_cache(p->path, 0);
 155                 else
 156                         remove_file_from_cache(p->path);
 157         }
 158 }
 159
 160 static char *prepare_index(const char **files, const char *prefix)
 161 {
 162         int fd;
 163         struct tree *tree;
 164         struct path_list partial;
 165         const char **pathspec = NULL;
 166
 167         if (interactive) {
 168                 interactive_add();
 169                 commit_style = COMMIT_AS_IS;
 170                 return get_index_file();
 171         }
 172
 173         if (read_cache() < 0)
 174                 die("index file corrupt");
 175
 176         if (*files)
 177                 pathspec = get_pathspec(prefix, files);
 178
 179         /*
 180          * Non partial, non as-is commit.
 181          *
 182          * (1) get the real index;
 183          * (2) update the_index as necessary;
 184          * (3) write the_index out to the real index (still locked);
 185          * (4) return the name of the locked index file.
 186          *
 187          * The caller should run hooks on the locked real index, and
 188          * (A) if all goes well, commit the real index;
 189          * (B) on failure, rollback the real index.
 190          */
 191         if (all || (also && pathspec && *pathspec)) {
 192                 int fd = hold_locked_index(&index_lock, 1);
 193                 add_files_to_cache(0, also ? prefix : NULL, pathspec);
 194                 refresh_cache(REFRESH_QUIET);
 195                 if (write_cache(fd, active_cache, active_nr) || close(fd))
 196                         die("unable to write new_index file");
 197                 commit_style = COMMIT_NORMAL;
 198                 return index_lock.filename;
 199         }
 200
 201         /*
 202          * As-is commit.
 203          *
 204          * (1) return the name of the real index file.
 205          *
 206          * The caller should run hooks on the real index, and run
 207          * hooks on the real index, and create commit from the_index.
 208          * We still need to refresh the index here.
 209          */
 210         if (!pathspec || !*pathspec) {
 211                 fd = hold_locked_index(&index_lock, 1);
 212                 refresh_cache(REFRESH_QUIET);
 213                 if (write_cache(fd, active_cache, active_nr) ||
 214                     close(fd) || commit_locked_index(&index_lock))
 215                         die("unable to write new_index file");
 216                 commit_style = COMMIT_AS_IS;
 217                 return get_index_file();
 218         }
 219
 220         /*
 221          * A partial commit.
 222          *
 223          * (0) find the set of affected paths;
 224          * (1) get lock on the real index file;
 225          * (2) update the_index with the given paths;
 226          * (3) write the_index out to the real index (still locked);
 227          * (4) get lock on the false index file;
 228          * (5) reset the_index from HEAD;
 229          * (6) update the_index the same way as (2);
 230          * (7) write the_index out to the false index file;
 231          * (8) return the name of the false index file (still locked);
 232          *
 233          * The caller should run hooks on the locked false index, and
 234          * create commit from it.  Then
 235          * (A) if all goes well, commit the real index;
 236          * (B) on failure, rollback the real index;
 237          * In either case, rollback the false index.
 238          */
 239         commit_style = COMMIT_PARTIAL;
 240
 241         if (file_exists(git_path("MERGE_HEAD")))
 242                 die("cannot do a partial commit during a merge.");
 243
 244         memset(&partial, 0, sizeof(partial));
 245         partial.strdup_paths = 1;
 246         if (list_paths(&partial, initial_commit ? NULL : "HEAD", prefix, pathspec))
 247                 exit(1);
 248
 249         discard_cache();
 250         if (read_cache() < 0)
 251                 die("cannot read the index");
 252
 253         fd = hold_locked_index(&index_lock, 1);
 254         add_remove_files(&partial);
 255         refresh_cache(REFRESH_QUIET);
 256         if (write_cache(fd, active_cache, active_nr) || close(fd))
 257                 die("unable to write new_index file");
 258
 259         fd = hold_lock_file_for_update(&false_lock,
 260                                        git_path("next-index-%d", getpid()), 1);
 261         discard_cache();
 262         if (!initial_commit) {
 263                 tree = parse_tree_indirect(head_sha1);
 264                 if (!tree)
 265                         die("failed to unpack HEAD tree object");
 266                 if (read_tree(tree, 0, NULL))
 267                         die("failed to read HEAD tree object");
 268         }
 269         add_remove_files(&partial);
 270         refresh_cache(REFRESH_QUIET);
 271
 272         if (write_cache(fd, active_cache, active_nr) || close(fd))
 273                 die("unable to write temporary index file");
 274         return false_lock.filename;
 275 }
 276
 277 static int run_status(FILE *fp, const char *index_file, const char *prefix)
 278 {
 279         struct wt_status s;
 280
 281         wt_status_prepare(&s);
 282         s.prefix = prefix;
 283
 284         if (amend) {
 285                 s.amend = 1;
 286                 s.reference = "HEAD^1";
 287         }
 288         s.verbose = verbose;
 289         s.untracked = untracked_files;
 290         s.index_file = index_file;
 291         s.fp = fp;
 292
 293         wt_status_print(&s);
 294
 295         return s.commitable;
 296 }
 297
 298 static const char sign_off_header[] = "Signed-off-by: ";
 299
 300 static int prepare_log_message(const char *index_file, const char *prefix)
 301 {
 302         struct stat statbuf;
 303         int commitable, saved_color_setting;
 304         struct strbuf sb;
 305         char *buffer;
 306         FILE *fp;
 307
 308         strbuf_init(&sb, 0);
 309         if (message.len) {
 310                 strbuf_addbuf(&sb, &message);
 311         } else if (logfile && !strcmp(logfile, "-")) {
 312                 if (isatty(0))
 313                         fprintf(stderr, "(reading log message from standard input)\n");
 314                 if (strbuf_read(&sb, 0, 0) < 0)
 315                         die("could not read log from standard input");
 316         } else if (logfile) {
 317                 if (strbuf_read_file(&sb, logfile, 0) < 0)
 318                         die("could not read log file '%s': %s",
 319                             logfile, strerror(errno));
 320         } else if (use_message) {
 321                 buffer = strstr(use_message_buffer, "\n\n");
 322                 if (!buffer || buffer[2] == '\0')
 323                         die("commit has empty message");
 324                 strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
 325         } else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
 326                 if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
 327                         die("could not read MERGE_MSG: %s", strerror(errno));
 328         } else if (!stat(git_path("SQUASH_MSG"), &statbuf)) {
 329                 if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
 330                         die("could not read SQUASH_MSG: %s", strerror(errno));
 331         } else if (template_file && !stat(template_file, &statbuf)) {
 332                 if (strbuf_read_file(&sb, template_file, 0) < 0)
 333                         die("could not read %s: %s",
 334                             template_file, strerror(errno));
 335         }
 336
 337         fp = fopen(git_path(commit_editmsg), "w");
 338         if (fp == NULL)
 339                 die("could not open %s\n", git_path(commit_editmsg));
 340
 341         stripspace(&sb, 0);
 342
 343         if (signoff) {
 344                 struct strbuf sob;
 345                 int i;
 346
 347                 strbuf_init(&sob, 0);
 348                 strbuf_addstr(&sob, sign_off_header);
 349                 strbuf_addstr(&sob, fmt_ident(getenv("GIT_COMMITTER_NAME"),
 350                                               getenv("GIT_COMMITTER_EMAIL"),
 351                                               "", 1));
 352                 strbuf_addch(&sob, '\n');
 353
 354                 for (i = sb.len - 1; i > 0 && sb.buf[i - 1] != '\n'; i--)
 355                         ; /* do nothing */
 356                 if (prefixcmp(sb.buf + i, sob.buf)) {
 357                         if (prefixcmp(sb.buf + i, sign_off_header))
 358                                 strbuf_addch(&sb, '\n');
 359                         strbuf_addbuf(&sb, &sob);
 360                 }
 361                 strbuf_release(&sob);
 362         }
 363
 364         if (fwrite(sb.buf, 1, sb.len, fp) < sb.len)
 365                 die("could not write commit template: %s\n",
 366                     strerror(errno));
 367
 368         strbuf_release(&sb);
 369
 370         if (in_merge && !no_edit)
 371                 fprintf(fp,
 372                         "#\n"
 373                         "# It looks like you may be committing a MERGE.\n"
 374                         "# If this is not correct, please remove the file\n"
 375                         "#      %s\n"
 376                         "# and try again.\n"
 377                         "#\n",
 378                         git_path("MERGE_HEAD"));
 379
 380         fprintf(fp,
 381                 "\n"
 382                 "# Please enter the commit message for your changes.\n"
 383                 "# (Comment lines starting with '#' will not be included)\n");
 384         if (only_include_assumed)
 385                 fprintf(fp, "# %s\n", only_include_assumed);
 386
 387         saved_color_setting = wt_status_use_color;
 388         wt_status_use_color = 0;
 389         commitable = run_status(fp, index_file, prefix);
 390         wt_status_use_color = saved_color_setting;
 391
 392         fclose(fp);
 393
 394         return commitable;
 395 }
 396
 397 /*
 398  * Find out if the message starting at position 'start' in the strbuf
 399  * contains only whitespace and Signed-off-by lines.
 400  */
 401 static int message_is_empty(struct strbuf *sb, int start)
 402 {
 403         struct strbuf tmpl;
 404         const char *nl;
 405         int eol, i;
 406
 407         /* See if the template is just a prefix of the message. */
 408         strbuf_init(&tmpl, 0);
 409         if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
 410                 stripspace(&tmpl, 1);
 411                 if (start + tmpl.len <= sb->len &&
 412                     memcmp(tmpl.buf, sb->buf + start, tmpl.len) == 0)
 413                         start += tmpl.len;
 414         }
 415         strbuf_release(&tmpl);
 416
 417         /* Check if the rest is just whitespace and Signed-of-by's. */
 418         for (i = start; i < sb->len; i++) {
 419                 nl = memchr(sb->buf + i, '\n', sb->len - i);
 420                 if (nl)
 421                         eol = nl - sb->buf;
 422                 else
 423                         eol = sb->len;
 424
 425                 if (strlen(sign_off_header) <= eol - i &&
 426                     !prefixcmp(sb->buf + i, sign_off_header)) {
 427                         i = eol;
 428                         continue;
 429                 }
 430                 while (i < eol)
 431                         if (!isspace(sb->buf[i++]))
 432                                 return 0;
 433         }
 434
 435         return 1;
 436 }
 437
 438 static void determine_author_info(struct strbuf *sb)
 439 {
 440         char *name, *email, *date;
 441
 442         name = getenv("GIT_AUTHOR_NAME");
 443         email = getenv("GIT_AUTHOR_EMAIL");
 444         date = getenv("GIT_AUTHOR_DATE");
 445
 446         if (use_message) {
 447                 const char *a, *lb, *rb, *eol;
 448
 449                 a = strstr(use_message_buffer, "\nauthor ");
 450                 if (!a)
 451                         die("invalid commit: %s\n", use_message);
 452
 453                 lb = strstr(a + 8, " <");
 454                 rb = strstr(a + 8, "> ");
 455                 eol = strchr(a + 8, '\n');
 456                 if (!lb || !rb || !eol)
 457                         die("invalid commit: %s\n", use_message);
 458
 459                 name = xstrndup(a + 8, lb - (a + 8));
 460                 email = xstrndup(lb + 2, rb - (lb + 2));
 461                 date = xstrndup(rb + 2, eol - (rb + 2));
 462         }
 463
 464         if (force_author) {
 465                 const char *lb = strstr(force_author, " <");
 466                 const char *rb = strchr(force_author, '>');
 467
 468                 if (!lb || !rb)
 469                         die("malformed --author parameter\n");
 470                 name = xstrndup(force_author, lb - force_author);
 471                 email = xstrndup(lb + 2, rb - (lb + 2));
 472         }
 473
 474         strbuf_addf(sb, "author %s\n", fmt_ident(name, email, date, 1));
 475 }
 476
 477 static int parse_and_validate_options(int argc, const char *argv[])
 478 {
 479         int f = 0;
 480
 481         argc = parse_options(argc, argv, builtin_commit_options,
 482                              builtin_commit_usage, 0);
 483
 484         if (logfile || message.len || use_message)
 485                 no_edit = 1;
 486         if (edit_flag)
 487                 no_edit = 0;
 488
 489         if (get_sha1("HEAD", head_sha1))
 490                 initial_commit = 1;
 491
 492         if (!get_sha1("MERGE_HEAD", merge_head_sha1))
 493                 in_merge = 1;
 494
 495         /* Sanity check options */
 496         if (amend && initial_commit)
 497                 die("You have nothing to amend.");
 498         if (amend && in_merge)
 499                 die("You are in the middle of a merger -- cannot amend.");
 500
 501         if (use_message)
 502                 f++;
 503         if (edit_message)
 504                 f++;
 505         if (logfile)
 506                 f++;
 507         if (f > 1)
 508                 die("Only one of -c/-C/-F can be used.");
 509         if (message.len && f > 0)
 510                 die("Option -m cannot be combined with -c/-C/-F.");
 511         if (edit_message)
 512                 use_message = edit_message;
 513         if (amend)
 514                 use_message = "HEAD";
 515         if (use_message) {
 516                 unsigned char sha1[20];
 517                 static char utf8[] = "UTF-8";
 518                 const char *out_enc;
 519                 char *enc, *end;
 520                 struct commit *commit;
 521
 522                 if (get_sha1(use_message, sha1))
 523                         die("could not lookup commit %s", use_message);
 524                 commit = lookup_commit(sha1);
 525                 if (!commit || parse_commit(commit))
 526                         die("could not parse commit %s", use_message);
 527
 528                 enc = strstr(commit->buffer, "\nencoding");
 529                 if (enc) {
 530                         end = strchr(enc + 10, '\n');
 531                         enc = xstrndup(enc + 10, end - (enc + 10));
 532                 } else {
 533                         enc = utf8;
 534                 }
 535                 out_enc = git_commit_encoding ? git_commit_encoding : utf8;
 536
 537                 if (strcmp(out_enc, enc))
 538                         use_message_buffer =
 539                                 reencode_string(commit->buffer, out_enc, enc);
 540
 541                 /*
 542                  * If we failed to reencode the buffer, just copy it
 543                  * byte for byte so the user can try to fix it up.
 544                  * This also handles the case where input and output
 545                  * encodings are identical.
 546                  */
 547                 if (use_message_buffer == NULL)
 548                         use_message_buffer = xstrdup(commit->buffer);
 549                 if (enc != utf8)
 550                         free(enc);
 551         }
 552
 553         if (!!also + !!only + !!all + !!interactive > 1)
 554                 die("Only one of --include/--only/--all/--interactive can be used.");
 555         if (argc == 0 && (also || (only && !amend)))
 556                 die("No paths with --include/--only does not make sense.");
 557         if (argc == 0 && only && amend)
 558                 only_include_assumed = "Clever... amending the last one with dirty index.";
 559         if (argc > 0 && !also && !only) {
 560                 only_include_assumed = "Explicit paths specified without -i nor -o; assuming --only paths...";
 561                 also = 0;
 562         }
 563
 564         if (all && argc > 0)
 565                 die("Paths with -a does not make sense.");
 566         else if (interactive && argc > 0)
 567                 die("Paths with --interactive does not make sense.");
 568
 569         return argc;
 570 }
 571
 572 int cmd_status(int argc, const char **argv, const char *prefix)
 573 {
 574         const char *index_file;
 575         int commitable;
 576
 577         git_config(git_status_config);
 578
 579         argc = parse_and_validate_options(argc, argv);
 580
 581         index_file = prepare_index(argv, prefix);
 582
 583         commitable = run_status(stdout, index_file, prefix);
 584
 585         rollback_index_files();
 586
 587         return commitable ? 0 : 1;
 588 }
 589
 590 static int run_hook(const char *index_file, const char *name, const char *arg)
 591 {
 592         struct child_process hook;
 593         const char *argv[3], *env[2];
 594         char index[PATH_MAX];
 595
 596         argv[0] = git_path("hooks/%s", name);
 597         argv[1] = arg;
 598         argv[2] = NULL;
 599         snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 600         env[0] = index;
 601         env[1] = NULL;
 602
 603         if (access(argv[0], X_OK) < 0)
 604                 return 0;
 605
 606         memset(&hook, 0, sizeof(hook));
 607         hook.argv = argv;
 608         hook.no_stdin = 1;
 609         hook.stdout_to_stderr = 1;
 610         hook.env = env;
 611
 612         return run_command(&hook);
 613 }
 614
 615 static void print_summary(const char *prefix, const unsigned char *sha1)
 616 {
 617         struct rev_info rev;
 618         struct commit *commit;
 619
 620         commit = lookup_commit(sha1);
 621         if (!commit)
 622                 die("couldn't look up newly created commit\n");
 623         if (!commit || parse_commit(commit))
 624                 die("could not parse newly created commit");
 625
 626         init_revisions(&rev, prefix);
 627         setup_revisions(0, NULL, &rev, NULL);
 628
 629         rev.abbrev = 0;
 630         rev.diff = 1;
 631         rev.diffopt.output_format =
 632                 DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
 633
 634         rev.verbose_header = 1;
 635         rev.show_root_diff = 1;
 636         rev.commit_format = get_commit_format("format:%h: %s");
 637         rev.always_show_header = 1;
 638
 639         printf("Created %scommit ", initial_commit ? "initial " : "");
 640
 641         log_tree_commit(&rev, commit);
 642         printf("\n");
 643 }
 644
 645 int git_commit_config(const char *k, const char *v)
 646 {
 647         if (!strcmp(k, "commit.template")) {
 648                 template_file = xstrdup(v);
 649                 return 0;
 650         }
 651
 652         return git_status_config(k, v);
 653 }
 654
 655 static const char commit_utf8_warn[] =
 656 "Warning: commit message does not conform to UTF-8.\n"
 657 "You may want to amend it after fixing the message, or set the config\n"
 658 "variable i18n.commitencoding to the encoding your project uses.\n";
 659
 660 int cmd_commit(int argc, const char **argv, const char *prefix)
 661 {
 662         int header_len;
 663         struct strbuf sb;
 664         const char *index_file, *reflog_msg;
 665         char *nl;
 666         unsigned char commit_sha1[20];
 667         struct ref_lock *ref_lock;
 668
 669         git_config(git_commit_config);
 670
 671         argc = parse_and_validate_options(argc, argv);
 672
 673         index_file = prepare_index(argv, prefix);
 674
 675         if (!no_verify && run_hook(index_file, "pre-commit", NULL)) {
 676                 rollback_index_files();
 677                 return 1;
 678         }
 679
 680         if (!prepare_log_message(index_file, prefix) && !in_merge) {
 681                 run_status(stdout, index_file, prefix);
 682                 rollback_index_files();
 683                 unlink(commit_editmsg);
 684                 return 1;
 685         }
 686
 687         /*
 688          * Re-read the index as pre-commit hook could have updated it,
 689          * and write it out as a tree.
 690          */
 691         discard_cache();
 692         read_cache_from(index_file);
 693         if (!active_cache_tree)
 694                 active_cache_tree = cache_tree();
 695         if (cache_tree_update(active_cache_tree,
 696                               active_cache, active_nr, 0, 0) < 0) {
 697                 rollback_index_files();
 698                 die("Error building trees");
 699         }
 700
 701         /*
 702          * The commit object
 703          */
 704         strbuf_init(&sb, 0);
 705         strbuf_addf(&sb, "tree %s\n",
 706                     sha1_to_hex(active_cache_tree->sha1));
 707
 708         /* Determine parents */
 709         if (initial_commit) {
 710                 reflog_msg = "commit (initial)";
 711         } else if (amend) {
 712                 struct commit_list *c;
 713                 struct commit *commit;
 714
 715                 reflog_msg = "commit (amend)";
 716                 commit = lookup_commit(head_sha1);
 717                 if (!commit || parse_commit(commit))
 718                         die("could not parse HEAD commit");
 719
 720                 for (c = commit->parents; c; c = c->next)
 721                         strbuf_addf(&sb, "parent %s\n",
 722                                       sha1_to_hex(c->item->object.sha1));
 723         } else if (in_merge) {
 724                 struct strbuf m;
 725                 FILE *fp;
 726
 727                 reflog_msg = "commit (merge)";
 728                 strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
 729                 strbuf_init(&m, 0);
 730                 fp = fopen(git_path("MERGE_HEAD"), "r");
 731                 if (fp == NULL)
 732                         die("could not open %s for reading: %s",
 733                             git_path("MERGE_HEAD"), strerror(errno));
 734                 while (strbuf_getline(&m, fp, '\n') != EOF)
 735                         strbuf_addf(&sb, "parent %s\n", m.buf);
 736                 fclose(fp);
 737                 strbuf_release(&m);
 738         } else {
 739                 reflog_msg = "commit";
 740                 strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
 741         }
 742
 743         determine_author_info(&sb);
 744         strbuf_addf(&sb, "committer %s\n", git_committer_info(1));
 745         if (!is_encoding_utf8(git_commit_encoding))
 746                 strbuf_addf(&sb, "encoding %s\n", git_commit_encoding);
 747         strbuf_addch(&sb, '\n');
 748
 749         /* Get the commit message and validate it */
 750         header_len = sb.len;
 751         if (!no_edit)
 752                 launch_editor(git_path(commit_editmsg), &sb);
 753         else if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
 754                 rollback_index_files();
 755                 die("could not read commit message\n");
 756         }
 757         if (run_hook(index_file, "commit-msg", git_path(commit_editmsg))) {
 758                 rollback_index_files();
 759                 exit(1);
 760         }
 761         stripspace(&sb, 1);
 762         if (sb.len < header_len || message_is_empty(&sb, header_len)) {
 763                 rollback_index_files();
 764                 die("* no commit message?  aborting commit.");
 765         }
 766         strbuf_addch(&sb, '\0');
 767         if (is_encoding_utf8(git_commit_encoding) && !is_utf8(sb.buf))
 768                 fprintf(stderr, commit_utf8_warn);
 769
 770         if (write_sha1_file(sb.buf, sb.len - 1, commit_type, commit_sha1)) {
 771                 rollback_index_files();
 772                 die("failed to write commit object");
 773         }
 774
 775         ref_lock = lock_any_ref_for_update("HEAD",
 776                                            initial_commit ? NULL : head_sha1,
 777                                            0);
 778
 779         nl = strchr(sb.buf + header_len, '\n');
 780         if (nl)
 781                 strbuf_setlen(&sb, nl + 1 - sb.buf);
 782         else
 783                 strbuf_addch(&sb, '\n');
 784         strbuf_remove(&sb, 0, header_len);
 785         strbuf_insert(&sb, 0, reflog_msg, strlen(reflog_msg));
 786         strbuf_insert(&sb, strlen(reflog_msg), ": ", 2);
 787
 788         if (!ref_lock) {
 789                 rollback_index_files();
 790                 die("cannot lock HEAD ref");
 791         }
 792         if (write_ref_sha1(ref_lock, commit_sha1, sb.buf) < 0) {
 793                 rollback_index_files();
 794                 die("cannot update HEAD ref");
 795         }
 796
 797         unlink(git_path("MERGE_HEAD"));
 798         unlink(git_path("MERGE_MSG"));
 799
 800         commit_index_files();
 801
 802         rerere();
 803         run_hook(get_index_file(), "post-commit", NULL);
 804         if (!quiet)
 805                 print_summary(prefix, commit_sha1);
 806
 807         return 0;
 808 }