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 const char * const builtin_status_usage[] = {
  31         "git-status [options] [--] <filepattern>...",
  32         NULL
  33 };
  34
  35 static unsigned char head_sha1[20], merge_head_sha1[20];
  36 static char *use_message_buffer;
  37 static const char commit_editmsg[] = "COMMIT_EDITMSG";
  38 static struct lock_file index_lock; /* real index */
  39 static struct lock_file false_lock; /* used only for partial commits */
  40 static enum {
  41         COMMIT_AS_IS = 1,
  42         COMMIT_NORMAL,
  43         COMMIT_PARTIAL,
  44 } commit_style;
  45
  46 static char *logfile, *force_author, *template_file;
  47 static char *edit_message, *use_message;
  48 static int all, edit_flag, also, interactive, only, amend, signoff;
  49 static int quiet, verbose, untracked_files, no_verify, allow_empty;
  50
  51 static int no_edit, initial_commit, in_merge;
  52 const char *only_include_assumed;
  53 struct strbuf message;
  54
  55 static int opt_parse_m(const struct option *opt, const char *arg, int unset)
  56 {
  57         struct strbuf *buf = opt->value;
  58         if (unset)
  59                 strbuf_setlen(buf, 0);
  60         else {
  61                 strbuf_addstr(buf, arg);
  62                 strbuf_addch(buf, '\n');
  63                 strbuf_addch(buf, '\n');
  64         }
  65         return 0;
  66 }
  67
  68 static struct option builtin_commit_options[] = {
  69         OPT__QUIET(&quiet),
  70         OPT__VERBOSE(&verbose),
  71         OPT_GROUP("Commit message options"),
  72
  73         OPT_STRING('F', "file", &logfile, "FILE", "read log from file"),
  74         OPT_STRING(0, "author", &force_author, "AUTHOR", "override author for commit"),
  75         OPT_CALLBACK('m', "message", &message, "MESSAGE", "specify commit message", opt_parse_m),
  76         OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit "),
  77         OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
  78         OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by: header"),
  79         OPT_STRING('t', "template", &template_file, "FILE", "use specified template file"),
  80         OPT_BOOLEAN('e', "edit", &edit_flag, "force edit of commit"),
  81
  82         OPT_GROUP("Commit contents options"),
  83         OPT_BOOLEAN('a', "all", &all, "commit all changed files"),
  84         OPT_BOOLEAN('i', "include", &also, "add specified files to index for commit"),
  85         OPT_BOOLEAN(0, "interactive", &interactive, "interactively add files"),
  86         OPT_BOOLEAN('o', "only", &only, ""),
  87         OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
  88         OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
  89         OPT_BOOLEAN(0, "untracked-files", &untracked_files, "show all untracked files"),
  90         OPT_BOOLEAN(0, "allow-empty", &allow_empty, "ok to record an empty change"),
  91
  92         OPT_END()
  93 };
  94
  95 static void rollback_index_files(void)
  96 {
  97         switch (commit_style) {
  98         case COMMIT_AS_IS:
  99                 break; /* nothing to do */
 100         case COMMIT_NORMAL:
 101                 rollback_lock_file(&index_lock);
 102                 break;
 103         case COMMIT_PARTIAL:
 104                 rollback_lock_file(&index_lock);
 105                 rollback_lock_file(&false_lock);
 106                 break;
 107         }
 108 }
 109
 110 static void commit_index_files(void)
 111 {
 112         switch (commit_style) {
 113         case COMMIT_AS_IS:
 114                 break; /* nothing to do */
 115         case COMMIT_NORMAL:
 116                 commit_lock_file(&index_lock);
 117                 break;
 118         case COMMIT_PARTIAL:
 119                 commit_lock_file(&index_lock);
 120                 rollback_lock_file(&false_lock);
 121                 break;
 122         }
 123 }
 124
 125 /*
 126  * Take a union of paths in the index and the named tree (typically, "HEAD"),
 127  * and return the paths that match the given pattern in list.
 128  */
 129 static int list_paths(struct path_list *list, const char *with_tree,
 130                       const char *prefix, const char **pattern)
 131 {
 132         int i;
 133         char *m;
 134
 135         for (i = 0; pattern[i]; i++)
 136                 ;
 137         m = xcalloc(1, i);
 138
 139         if (with_tree)
 140                 overlay_tree_on_cache(with_tree, prefix);
 141
 142         for (i = 0; i < active_nr; i++) {
 143                 struct cache_entry *ce = active_cache[i];
 144                 if (ce->ce_flags & htons(CE_UPDATE))
 145                         continue;
 146                 if (!pathspec_match(pattern, m, ce->name, 0))
 147                         continue;
 148                 path_list_insert(ce->name, list);
 149         }
 150
 151         return report_path_error(m, pattern, prefix ? strlen(prefix) : 0);
 152 }
 153
 154 static void add_remove_files(struct path_list *list)
 155 {
 156         int i;
 157         for (i = 0; i < list->nr; i++) {
 158                 struct path_list_item *p = &(list->items[i]);
 159                 if (file_exists(p->path))
 160                         add_file_to_cache(p->path, 0);
 161                 else
 162                         remove_file_from_cache(p->path);
 163         }
 164 }
 165
 166 static char *prepare_index(int argc, const char **argv, const char *prefix)
 167 {
 168         int fd;
 169         struct tree *tree;
 170         struct path_list partial;
 171         const char **pathspec = NULL;
 172
 173         if (interactive) {
 174                 interactive_add(argc, argv, prefix);
 175                 commit_style = COMMIT_AS_IS;
 176                 return get_index_file();
 177         }
 178
 179         if (read_cache() < 0)
 180                 die("index file corrupt");
 181
 182         if (*argv)
 183                 pathspec = get_pathspec(prefix, argv);
 184
 185         /*
 186          * Non partial, non as-is commit.
 187          *
 188          * (1) get the real index;
 189          * (2) update the_index as necessary;
 190          * (3) write the_index out to the real index (still locked);
 191          * (4) return the name of the locked index file.
 192          *
 193          * The caller should run hooks on the locked real index, and
 194          * (A) if all goes well, commit the real index;
 195          * (B) on failure, rollback the real index.
 196          */
 197         if (all || (also && pathspec && *pathspec)) {
 198                 int fd = hold_locked_index(&index_lock, 1);
 199                 add_files_to_cache(0, also ? prefix : NULL, pathspec);
 200                 refresh_cache(REFRESH_QUIET);
 201                 if (write_cache(fd, active_cache, active_nr) || close(fd))
 202                         die("unable to write new_index file");
 203                 commit_style = COMMIT_NORMAL;
 204                 return index_lock.filename;
 205         }
 206
 207         /*
 208          * As-is commit.
 209          *
 210          * (1) return the name of the real index file.
 211          *
 212          * The caller should run hooks on the real index, and run
 213          * hooks on the real index, and create commit from the_index.
 214          * We still need to refresh the index here.
 215          */
 216         if (!pathspec || !*pathspec) {
 217                 fd = hold_locked_index(&index_lock, 1);
 218                 refresh_cache(REFRESH_QUIET);
 219                 if (write_cache(fd, active_cache, active_nr) ||
 220                     close(fd) || commit_locked_index(&index_lock))
 221                         die("unable to write new_index file");
 222                 commit_style = COMMIT_AS_IS;
 223                 return get_index_file();
 224         }
 225
 226         /*
 227          * A partial commit.
 228          *
 229          * (0) find the set of affected paths;
 230          * (1) get lock on the real index file;
 231          * (2) update the_index with the given paths;
 232          * (3) write the_index out to the real index (still locked);
 233          * (4) get lock on the false index file;
 234          * (5) reset the_index from HEAD;
 235          * (6) update the_index the same way as (2);
 236          * (7) write the_index out to the false index file;
 237          * (8) return the name of the false index file (still locked);
 238          *
 239          * The caller should run hooks on the locked false index, and
 240          * create commit from it.  Then
 241          * (A) if all goes well, commit the real index;
 242          * (B) on failure, rollback the real index;
 243          * In either case, rollback the false index.
 244          */
 245         commit_style = COMMIT_PARTIAL;
 246
 247         if (file_exists(git_path("MERGE_HEAD")))
 248                 die("cannot do a partial commit during a merge.");
 249
 250         memset(&partial, 0, sizeof(partial));
 251         partial.strdup_paths = 1;
 252         if (list_paths(&partial, initial_commit ? NULL : "HEAD", prefix, pathspec))
 253                 exit(1);
 254
 255         discard_cache();
 256         if (read_cache() < 0)
 257                 die("cannot read the index");
 258
 259         fd = hold_locked_index(&index_lock, 1);
 260         add_remove_files(&partial);
 261         refresh_cache(REFRESH_QUIET);
 262         if (write_cache(fd, active_cache, active_nr) || close(fd))
 263                 die("unable to write new_index file");
 264
 265         fd = hold_lock_file_for_update(&false_lock,
 266                                        git_path("next-index-%d", getpid()), 1);
 267         discard_cache();
 268         if (!initial_commit) {
 269                 tree = parse_tree_indirect(head_sha1);
 270                 if (!tree)
 271                         die("failed to unpack HEAD tree object");
 272                 if (read_tree(tree, 0, NULL))
 273                         die("failed to read HEAD tree object");
 274         }
 275         add_remove_files(&partial);
 276         refresh_cache(REFRESH_QUIET);
 277
 278         if (write_cache(fd, active_cache, active_nr) || close(fd))
 279                 die("unable to write temporary index file");
 280         return false_lock.filename;
 281 }
 282
 283 static int run_status(FILE *fp, const char *index_file, const char *prefix, int nowarn)
 284 {
 285         struct wt_status s;
 286
 287         wt_status_prepare(&s);
 288         if (wt_status_relative_paths)
 289                 s.prefix = prefix;
 290
 291         if (amend) {
 292                 s.amend = 1;
 293                 s.reference = "HEAD^1";
 294         }
 295         s.verbose = verbose;
 296         s.untracked = untracked_files;
 297         s.index_file = index_file;
 298         s.fp = fp;
 299         s.nowarn = nowarn;
 300
 301         wt_status_print(&s);
 302
 303         return s.commitable;
 304 }
 305
 306 static const char sign_off_header[] = "Signed-off-by: ";
 307
 308 static int prepare_log_message(const char *index_file, const char *prefix)
 309 {
 310         struct stat statbuf;
 311         int commitable, saved_color_setting;
 312         struct strbuf sb;
 313         char *buffer;
 314         FILE *fp;
 315
 316         strbuf_init(&sb, 0);
 317         if (message.len) {
 318                 strbuf_addbuf(&sb, &message);
 319         } else if (logfile && !strcmp(logfile, "-")) {
 320                 if (isatty(0))
 321                         fprintf(stderr, "(reading log message from standard input)\n");
 322                 if (strbuf_read(&sb, 0, 0) < 0)
 323                         die("could not read log from standard input");
 324         } else if (logfile) {
 325                 if (strbuf_read_file(&sb, logfile, 0) < 0)
 326                         die("could not read log file '%s': %s",
 327                             logfile, strerror(errno));
 328         } else if (use_message) {
 329                 buffer = strstr(use_message_buffer, "\n\n");
 330                 if (!buffer || buffer[2] == '\0')
 331                         die("commit has empty message");
 332                 strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
 333         } else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
 334                 if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
 335                         die("could not read MERGE_MSG: %s", strerror(errno));
 336         } else if (!stat(git_path("SQUASH_MSG"), &statbuf)) {
 337                 if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
 338                         die("could not read SQUASH_MSG: %s", strerror(errno));
 339         } else if (template_file && !stat(template_file, &statbuf)) {
 340                 if (strbuf_read_file(&sb, template_file, 0) < 0)
 341                         die("could not read %s: %s",
 342                             template_file, strerror(errno));
 343         }
 344
 345         fp = fopen(git_path(commit_editmsg), "w");
 346         if (fp == NULL)
 347                 die("could not open %s", git_path(commit_editmsg));
 348
 349         stripspace(&sb, 0);
 350
 351         if (signoff) {
 352                 struct strbuf sob;
 353                 int i;
 354
 355                 strbuf_init(&sob, 0);
 356                 strbuf_addstr(&sob, sign_off_header);
 357                 strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
 358                                              getenv("GIT_COMMITTER_EMAIL")));
 359                 strbuf_addch(&sob, '\n');
 360                 for (i = sb.len - 1; i > 0 && sb.buf[i - 1] != '\n'; i--)
 361                         ; /* do nothing */
 362                 if (prefixcmp(sb.buf + i, sob.buf)) {
 363                         if (prefixcmp(sb.buf + i, sign_off_header))
 364                                 strbuf_addch(&sb, '\n');
 365                         strbuf_addbuf(&sb, &sob);
 366                 }
 367                 strbuf_release(&sob);
 368         }
 369
 370         if (fwrite(sb.buf, 1, sb.len, fp) < sb.len)
 371                 die("could not write commit template: %s", strerror(errno));
 372
 373         strbuf_release(&sb);
 374
 375         if (no_edit) {
 376                 struct rev_info rev;
 377                 unsigned char sha1[40];
 378
 379                 fclose(fp);
 380
 381                 if (!active_nr && read_cache() < 0)
 382                         die("Cannot read index");
 383
 384                 if (get_sha1("HEAD", sha1) != 0)
 385                         return !!active_nr;
 386
 387                 init_revisions(&rev, "");
 388                 rev.abbrev = 0;
 389                 setup_revisions(0, NULL, &rev, "HEAD");
 390                 DIFF_OPT_SET(&rev.diffopt, QUIET);
 391                 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
 392                 run_diff_index(&rev, 1 /* cached */);
 393
 394                 return !!DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES);
 395         }
 396
 397         if (in_merge && !no_edit)
 398                 fprintf(fp,
 399                         "#\n"
 400                         "# It looks like you may be committing a MERGE.\n"
 401                         "# If this is not correct, please remove the file\n"
 402                         "#      %s\n"
 403                         "# and try again.\n"
 404                         "#\n",
 405                         git_path("MERGE_HEAD"));
 406
 407         fprintf(fp,
 408                 "\n"
 409                 "# Please enter the commit message for your changes.\n"
 410                 "# (Comment lines starting with '#' will not be included)\n");
 411         if (only_include_assumed)
 412                 fprintf(fp, "# %s\n", only_include_assumed);
 413
 414         saved_color_setting = wt_status_use_color;
 415         wt_status_use_color = 0;
 416         commitable = run_status(fp, index_file, prefix, 1);
 417         wt_status_use_color = saved_color_setting;
 418
 419         fclose(fp);
 420
 421         return commitable;
 422 }
 423
 424 /*
 425  * Find out if the message starting at position 'start' in the strbuf
 426  * contains only whitespace and Signed-off-by lines.
 427  */
 428 static int message_is_empty(struct strbuf *sb, int start)
 429 {
 430         struct strbuf tmpl;
 431         const char *nl;
 432         int eol, i;
 433
 434         /* See if the template is just a prefix of the message. */
 435         strbuf_init(&tmpl, 0);
 436         if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
 437                 stripspace(&tmpl, 1);
 438                 if (start + tmpl.len <= sb->len &&
 439                     memcmp(tmpl.buf, sb->buf + start, tmpl.len) == 0)
 440                         start += tmpl.len;
 441         }
 442         strbuf_release(&tmpl);
 443
 444         /* Check if the rest is just whitespace and Signed-of-by's. */
 445         for (i = start; i < sb->len; i++) {
 446                 nl = memchr(sb->buf + i, '\n', sb->len - i);
 447                 if (nl)
 448                         eol = nl - sb->buf;
 449                 else
 450                         eol = sb->len;
 451
 452                 if (strlen(sign_off_header) <= eol - i &&
 453                     !prefixcmp(sb->buf + i, sign_off_header)) {
 454                         i = eol;
 455                         continue;
 456                 }
 457                 while (i < eol)
 458                         if (!isspace(sb->buf[i++]))
 459                                 return 0;
 460         }
 461
 462         return 1;
 463 }
 464
 465 static void determine_author_info(struct strbuf *sb)
 466 {
 467         char *name, *email, *date;
 468
 469         name = getenv("GIT_AUTHOR_NAME");
 470         email = getenv("GIT_AUTHOR_EMAIL");
 471         date = getenv("GIT_AUTHOR_DATE");
 472
 473         if (use_message) {
 474                 const char *a, *lb, *rb, *eol;
 475
 476                 a = strstr(use_message_buffer, "\nauthor ");
 477                 if (!a)
 478                         die("invalid commit: %s", use_message);
 479
 480                 lb = strstr(a + 8, " <");
 481                 rb = strstr(a + 8, "> ");
 482                 eol = strchr(a + 8, '\n');
 483                 if (!lb || !rb || !eol)
 484                         die("invalid commit: %s", use_message);
 485
 486                 name = xstrndup(a + 8, lb - (a + 8));
 487                 email = xstrndup(lb + 2, rb - (lb + 2));
 488                 date = xstrndup(rb + 2, eol - (rb + 2));
 489         }
 490
 491         if (force_author) {
 492                 const char *lb = strstr(force_author, " <");
 493                 const char *rb = strchr(force_author, '>');
 494
 495                 if (!lb || !rb)
 496                         die("malformed --author parameter");
 497                 name = xstrndup(force_author, lb - force_author);
 498                 email = xstrndup(lb + 2, rb - (lb + 2));
 499         }
 500
 501         strbuf_addf(sb, "author %s\n", fmt_ident(name, email, date, IDENT_ERROR_ON_NO_NAME));
 502 }
 503
 504 static int parse_and_validate_options(int argc, const char *argv[],
 505                                       const char * const usage[])
 506 {
 507         int f = 0;
 508
 509         argc = parse_options(argc, argv, builtin_commit_options, usage, 0);
 510
 511         if (logfile || message.len || use_message)
 512                 no_edit = 1;
 513         if (edit_flag)
 514                 no_edit = 0;
 515
 516         if (get_sha1("HEAD", head_sha1))
 517                 initial_commit = 1;
 518
 519         if (!get_sha1("MERGE_HEAD", merge_head_sha1))
 520                 in_merge = 1;
 521
 522         /* Sanity check options */
 523         if (amend && initial_commit)
 524                 die("You have nothing to amend.");
 525         if (amend && in_merge)
 526                 die("You are in the middle of a merge -- cannot amend.");
 527
 528         if (use_message)
 529                 f++;
 530         if (edit_message)
 531                 f++;
 532         if (logfile)
 533                 f++;
 534         if (f > 1)
 535                 die("Only one of -c/-C/-F can be used.");
 536         if (message.len && f > 0)
 537                 die("Option -m cannot be combined with -c/-C/-F.");
 538         if (edit_message)
 539                 use_message = edit_message;
 540         if (amend && !use_message)
 541                 use_message = "HEAD";
 542         if (use_message) {
 543                 unsigned char sha1[20];
 544                 static char utf8[] = "UTF-8";
 545                 const char *out_enc;
 546                 char *enc, *end;
 547                 struct commit *commit;
 548
 549                 if (get_sha1(use_message, sha1))
 550                         die("could not lookup commit %s", use_message);
 551                 commit = lookup_commit(sha1);
 552                 if (!commit || parse_commit(commit))
 553                         die("could not parse commit %s", use_message);
 554
 555                 enc = strstr(commit->buffer, "\nencoding");
 556                 if (enc) {
 557                         end = strchr(enc + 10, '\n');
 558                         enc = xstrndup(enc + 10, end - (enc + 10));
 559                 } else {
 560                         enc = utf8;
 561                 }
 562                 out_enc = git_commit_encoding ? git_commit_encoding : utf8;
 563
 564                 if (strcmp(out_enc, enc))
 565                         use_message_buffer =
 566                                 reencode_string(commit->buffer, out_enc, enc);
 567
 568                 /*
 569                  * If we failed to reencode the buffer, just copy it
 570                  * byte for byte so the user can try to fix it up.
 571                  * This also handles the case where input and output
 572                  * encodings are identical.
 573                  */
 574                 if (use_message_buffer == NULL)
 575                         use_message_buffer = xstrdup(commit->buffer);
 576                 if (enc != utf8)
 577                         free(enc);
 578         }
 579
 580         if (!!also + !!only + !!all + !!interactive > 1)
 581                 die("Only one of --include/--only/--all/--interactive can be used.");
 582         if (argc == 0 && (also || (only && !amend)))
 583                 die("No paths with --include/--only does not make sense.");
 584         if (argc == 0 && only && amend)
 585                 only_include_assumed = "Clever... amending the last one with dirty index.";
 586         if (argc > 0 && !also && !only) {
 587                 only_include_assumed = "Explicit paths specified without -i nor -o; assuming --only paths...";
 588                 also = 0;
 589         }
 590
 591         if (all && argc > 0)
 592                 die("Paths with -a does not make sense.");
 593         else if (interactive && argc > 0)
 594                 die("Paths with --interactive does not make sense.");
 595
 596         return argc;
 597 }
 598
 599 int cmd_status(int argc, const char **argv, const char *prefix)
 600 {
 601         const char *index_file;
 602         int commitable;
 603
 604         git_config(git_status_config);
 605
 606         argc = parse_and_validate_options(argc, argv, builtin_status_usage);
 607
 608         index_file = prepare_index(argc, argv, prefix);
 609
 610         commitable = run_status(stdout, index_file, prefix, 0);
 611
 612         rollback_index_files();
 613
 614         return commitable ? 0 : 1;
 615 }
 616
 617 static int run_hook(const char *index_file, const char *name, const char *arg)
 618 {
 619         struct child_process hook;
 620         const char *argv[3], *env[2];
 621         char index[PATH_MAX];
 622
 623         argv[0] = git_path("hooks/%s", name);
 624         argv[1] = arg;
 625         argv[2] = NULL;
 626         snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 627         env[0] = index;
 628         env[1] = NULL;
 629
 630         if (access(argv[0], X_OK) < 0)
 631                 return 0;
 632
 633         memset(&hook, 0, sizeof(hook));
 634         hook.argv = argv;
 635         hook.no_stdin = 1;
 636         hook.stdout_to_stderr = 1;
 637         hook.env = env;
 638
 639         return run_command(&hook);
 640 }
 641
 642 static void print_summary(const char *prefix, const unsigned char *sha1)
 643 {
 644         struct rev_info rev;
 645         struct commit *commit;
 646
 647         commit = lookup_commit(sha1);
 648         if (!commit)
 649                 die("couldn't look up newly created commit");
 650         if (!commit || parse_commit(commit))
 651                 die("could not parse newly created commit");
 652
 653         init_revisions(&rev, prefix);
 654         setup_revisions(0, NULL, &rev, NULL);
 655
 656         rev.abbrev = 0;
 657         rev.diff = 1;
 658         rev.diffopt.output_format =
 659                 DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
 660
 661         rev.verbose_header = 1;
 662         rev.show_root_diff = 1;
 663         rev.commit_format = get_commit_format("format:%h: %s");
 664         rev.always_show_header = 0;
 665
 666         printf("Created %scommit ", initial_commit ? "initial " : "");
 667
 668         if (!log_tree_commit(&rev, commit)) {
 669                 struct strbuf buf = STRBUF_INIT;
 670                 format_commit_message(commit, "%h: %s", &buf);
 671                 printf("%s\n", buf.buf);
 672                 strbuf_release(&buf);
 673         }
 674 }
 675
 676 int git_commit_config(const char *k, const char *v)
 677 {
 678         if (!strcmp(k, "commit.template")) {
 679                 template_file = xstrdup(v);
 680                 return 0;
 681         }
 682
 683         return git_status_config(k, v);
 684 }
 685
 686 static int is_a_merge(const unsigned char *sha1)
 687 {
 688         struct commit *commit = lookup_commit(sha1);
 689         if (!commit || parse_commit(commit))
 690                 die("could not parse HEAD commit");
 691         return !!(commit->parents && commit->parents->next);
 692 }
 693
 694 static const char commit_utf8_warn[] =
 695 "Warning: commit message does not conform to UTF-8.\n"
 696 "You may want to amend it after fixing the message, or set the config\n"
 697 "variable i18n.commitencoding to the encoding your project uses.\n";
 698
 699 int cmd_commit(int argc, const char **argv, const char *prefix)
 700 {
 701         int header_len;
 702         struct strbuf sb;
 703         const char *index_file, *reflog_msg;
 704         char *nl, *p;
 705         unsigned char commit_sha1[20];
 706         struct ref_lock *ref_lock;
 707
 708         git_config(git_commit_config);
 709
 710         argc = parse_and_validate_options(argc, argv, builtin_commit_usage);
 711
 712         index_file = prepare_index(argc, argv, prefix);
 713
 714         if (!no_verify && run_hook(index_file, "pre-commit", NULL)) {
 715                 rollback_index_files();
 716                 return 1;
 717         }
 718
 719         if (!prepare_log_message(index_file, prefix) && !in_merge &&
 720             !allow_empty && !(amend && is_a_merge(head_sha1))) {
 721                 run_status(stdout, index_file, prefix, 0);
 722                 rollback_index_files();
 723                 unlink(commit_editmsg);
 724                 return 1;
 725         }
 726
 727         /*
 728          * Re-read the index as pre-commit hook could have updated it,
 729          * and write it out as a tree.
 730          */
 731         discard_cache();
 732         read_cache_from(index_file);
 733         if (!active_cache_tree)
 734                 active_cache_tree = cache_tree();
 735         if (cache_tree_update(active_cache_tree,
 736                               active_cache, active_nr, 0, 0) < 0) {
 737                 rollback_index_files();
 738                 die("Error building trees");
 739         }
 740
 741         /*
 742          * The commit object
 743          */
 744         strbuf_init(&sb, 0);
 745         strbuf_addf(&sb, "tree %s\n",
 746                     sha1_to_hex(active_cache_tree->sha1));
 747
 748         /* Determine parents */
 749         if (initial_commit) {
 750                 reflog_msg = "commit (initial)";
 751         } else if (amend) {
 752                 struct commit_list *c;
 753                 struct commit *commit;
 754
 755                 reflog_msg = "commit (amend)";
 756                 commit = lookup_commit(head_sha1);
 757                 if (!commit || parse_commit(commit))
 758                         die("could not parse HEAD commit");
 759
 760                 for (c = commit->parents; c; c = c->next)
 761                         strbuf_addf(&sb, "parent %s\n",
 762                                       sha1_to_hex(c->item->object.sha1));
 763         } else if (in_merge) {
 764                 struct strbuf m;
 765                 FILE *fp;
 766
 767                 reflog_msg = "commit (merge)";
 768                 strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
 769                 strbuf_init(&m, 0);
 770                 fp = fopen(git_path("MERGE_HEAD"), "r");
 771                 if (fp == NULL)
 772                         die("could not open %s for reading: %s",
 773                             git_path("MERGE_HEAD"), strerror(errno));
 774                 while (strbuf_getline(&m, fp, '\n') != EOF)
 775                         strbuf_addf(&sb, "parent %s\n", m.buf);
 776                 fclose(fp);
 777                 strbuf_release(&m);
 778         } else {
 779                 reflog_msg = "commit";
 780                 strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
 781         }
 782
 783         determine_author_info(&sb);
 784         strbuf_addf(&sb, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
 785         if (!is_encoding_utf8(git_commit_encoding))
 786                 strbuf_addf(&sb, "encoding %s\n", git_commit_encoding);
 787         strbuf_addch(&sb, '\n');
 788
 789         /* Get the commit message and validate it */
 790         header_len = sb.len;
 791         if (!no_edit) {
 792                 char index[PATH_MAX];
 793                 const char *env[2] = { index, NULL };
 794                 snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 795                 launch_editor(git_path(commit_editmsg), NULL, env);
 796         }
 797         if (!no_verify &&
 798             run_hook(index_file, "commit-msg", git_path(commit_editmsg))) {
 799                 rollback_index_files();
 800                 exit(1);
 801         }
 802         if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
 803                 rollback_index_files();
 804                 die("could not read commit message");
 805         }
 806
 807         /* Truncate the message just before the diff, if any. */
 808         p = strstr(sb.buf, "\ndiff --git a/");
 809         if (p != NULL)
 810                 strbuf_setlen(&sb, p - sb.buf + 1);
 811
 812         stripspace(&sb, 1);
 813         if (sb.len < header_len || message_is_empty(&sb, header_len)) {
 814                 rollback_index_files();
 815                 die("no commit message?  aborting commit.");
 816         }
 817         strbuf_addch(&sb, '\0');
 818         if (is_encoding_utf8(git_commit_encoding) && !is_utf8(sb.buf))
 819                 fprintf(stderr, commit_utf8_warn);
 820
 821         if (write_sha1_file(sb.buf, sb.len - 1, commit_type, commit_sha1)) {
 822                 rollback_index_files();
 823                 die("failed to write commit object");
 824         }
 825
 826         ref_lock = lock_any_ref_for_update("HEAD",
 827                                            initial_commit ? NULL : head_sha1,
 828                                            0);
 829
 830         nl = strchr(sb.buf + header_len, '\n');
 831         if (nl)
 832                 strbuf_setlen(&sb, nl + 1 - sb.buf);
 833         else
 834                 strbuf_addch(&sb, '\n');
 835         strbuf_remove(&sb, 0, header_len);
 836         strbuf_insert(&sb, 0, reflog_msg, strlen(reflog_msg));
 837         strbuf_insert(&sb, strlen(reflog_msg), ": ", 2);
 838
 839         if (!ref_lock) {
 840                 rollback_index_files();
 841                 die("cannot lock HEAD ref");
 842         }
 843         if (write_ref_sha1(ref_lock, commit_sha1, sb.buf) < 0) {
 844                 rollback_index_files();
 845                 die("cannot update HEAD ref");
 846         }
 847
 848         unlink(git_path("MERGE_HEAD"));
 849         unlink(git_path("MERGE_MSG"));
 850
 851         commit_index_files();
 852
 853         rerere();
 854         run_hook(get_index_file(), "post-commit", NULL);
 855         if (!quiet)
 856                 print_summary(prefix, commit_sha1);
 857
 858         return 0;
 859 }