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 "color.h"
  11 #include "dir.h"
  12 #include "builtin.h"
  13 #include "diff.h"
  14 #include "diffcore.h"
  15 #include "commit.h"
  16 #include "revision.h"
  17 #include "wt-status.h"
  18 #include "run-command.h"
  19 #include "refs.h"
  20 #include "log-tree.h"
  21 #include "strbuf.h"
  22 #include "utf8.h"
  23 #include "parse-options.h"
  24 #include "string-list.h"
  25 #include "rerere.h"
  26 #include "unpack-trees.h"
  27
  28 static const char * const builtin_commit_usage[] = {
  29         "git commit [options] [--] <filepattern>...",
  30         NULL
  31 };
  32
  33 static const char * const builtin_status_usage[] = {
  34         "git status [options] [--] <filepattern>...",
  35         NULL
  36 };
  37
  38 static unsigned char head_sha1[20], merge_head_sha1[20];
  39 static char *use_message_buffer;
  40 static const char commit_editmsg[] = "COMMIT_EDITMSG";
  41 static struct lock_file index_lock; /* real index */
  42 static struct lock_file false_lock; /* used only for partial commits */
  43 static enum {
  44         COMMIT_AS_IS = 1,
  45         COMMIT_NORMAL,
  46         COMMIT_PARTIAL,
  47 } commit_style;
  48
  49 static char *logfile, *force_author;
  50 static const char *template_file;
  51 static char *edit_message, *use_message;
  52 static char *author_name, *author_email, *author_date;
  53 static int all, edit_flag, also, interactive, only, amend, signoff;
  54 static int quiet, verbose, no_verify, allow_empty;
  55 static char *untracked_files_arg;
  56 /*
  57  * The default commit message cleanup mode will remove the lines
  58  * beginning with # (shell comments) and leading and trailing
  59  * whitespaces (empty lines or containing only whitespaces)
  60  * if editor is used, and only the whitespaces if the message
  61  * is specified explicitly.
  62  */
  63 static enum {
  64         CLEANUP_SPACE,
  65         CLEANUP_NONE,
  66         CLEANUP_ALL,
  67 } cleanup_mode;
  68 static char *cleanup_arg;
  69
  70 static int use_editor = 1, initial_commit, in_merge;
  71 const char *only_include_assumed;
  72 struct strbuf message;
  73
  74 static int opt_parse_m(const struct option *opt, const char *arg, int unset)
  75 {
  76         struct strbuf *buf = opt->value;
  77         if (unset)
  78                 strbuf_setlen(buf, 0);
  79         else {
  80                 strbuf_addstr(buf, arg);
  81                 strbuf_addch(buf, '\n');
  82                 strbuf_addch(buf, '\n');
  83         }
  84         return 0;
  85 }
  86
  87 static struct option builtin_commit_options[] = {
  88         OPT__QUIET(&quiet),
  89         OPT__VERBOSE(&verbose),
  90         OPT_GROUP("Commit message options"),
  91
  92         OPT_STRING('F', "file", &logfile, "FILE", "read log from file"),
  93         OPT_STRING(0, "author", &force_author, "AUTHOR", "override author for commit"),
  94         OPT_CALLBACK('m', "message", &message, "MESSAGE", "specify commit message", opt_parse_m),
  95         OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit "),
  96         OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
  97         OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
  98         OPT_STRING('t', "template", &template_file, "FILE", "use specified template file"),
  99         OPT_BOOLEAN('e', "edit", &edit_flag, "force edit of commit"),
 100
 101         OPT_GROUP("Commit contents options"),
 102         OPT_BOOLEAN('a', "all", &all, "commit all changed files"),
 103         OPT_BOOLEAN('i', "include", &also, "add specified files to index for commit"),
 104         OPT_BOOLEAN(0, "interactive", &interactive, "interactively add files"),
 105         OPT_BOOLEAN('o', "only", &only, "commit only specified files"),
 106         OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
 107         OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
 108         { OPTION_STRING, 'u', "untracked-files", &untracked_files_arg, "mode", "show untracked files, optional modes: all, normal, no. (Default: all)", PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
 109         OPT_BOOLEAN(0, "allow-empty", &allow_empty, "ok to record an empty change"),
 110         OPT_STRING(0, "cleanup", &cleanup_arg, "default", "how to strip spaces and #comments from message"),
 111
 112         OPT_END()
 113 };
 114
 115 static void rollback_index_files(void)
 116 {
 117         switch (commit_style) {
 118         case COMMIT_AS_IS:
 119                 break; /* nothing to do */
 120         case COMMIT_NORMAL:
 121                 rollback_lock_file(&index_lock);
 122                 break;
 123         case COMMIT_PARTIAL:
 124                 rollback_lock_file(&index_lock);
 125                 rollback_lock_file(&false_lock);
 126                 break;
 127         }
 128 }
 129
 130 static int commit_index_files(void)
 131 {
 132         int err = 0;
 133
 134         switch (commit_style) {
 135         case COMMIT_AS_IS:
 136                 break; /* nothing to do */
 137         case COMMIT_NORMAL:
 138                 err = commit_lock_file(&index_lock);
 139                 break;
 140         case COMMIT_PARTIAL:
 141                 err = commit_lock_file(&index_lock);
 142                 rollback_lock_file(&false_lock);
 143                 break;
 144         }
 145
 146         return err;
 147 }
 148
 149 /*
 150  * Take a union of paths in the index and the named tree (typically, "HEAD"),
 151  * and return the paths that match the given pattern in list.
 152  */
 153 static int list_paths(struct string_list *list, const char *with_tree,
 154                       const char *prefix, const char **pattern)
 155 {
 156         int i;
 157         char *m;
 158
 159         for (i = 0; pattern[i]; i++)
 160                 ;
 161         m = xcalloc(1, i);
 162
 163         if (with_tree)
 164                 overlay_tree_on_cache(with_tree, prefix);
 165
 166         for (i = 0; i < active_nr; i++) {
 167                 struct cache_entry *ce = active_cache[i];
 168                 if (ce->ce_flags & CE_UPDATE)
 169                         continue;
 170                 if (!pathspec_match(pattern, m, ce->name, 0))
 171                         continue;
 172                 string_list_insert(ce->name, list);
 173         }
 174
 175         return report_path_error(m, pattern, prefix ? strlen(prefix) : 0);
 176 }
 177
 178 static void add_remove_files(struct string_list *list)
 179 {
 180         int i;
 181         for (i = 0; i < list->nr; i++) {
 182                 struct stat st;
 183                 struct string_list_item *p = &(list->items[i]);
 184
 185                 if (!lstat(p->string, &st)) {
 186                         if (add_to_cache(p->string, &st, 0))
 187                                 die("updating files failed");
 188                 } else
 189                         remove_file_from_cache(p->string);
 190         }
 191 }
 192
 193 static void create_base_index(void)
 194 {
 195         struct tree *tree;
 196         struct unpack_trees_options opts;
 197         struct tree_desc t;
 198
 199         if (initial_commit) {
 200                 discard_cache();
 201                 return;
 202         }
 203
 204         memset(&opts, 0, sizeof(opts));
 205         opts.head_idx = 1;
 206         opts.index_only = 1;
 207         opts.merge = 1;
 208         opts.src_index = &the_index;
 209         opts.dst_index = &the_index;
 210
 211         opts.fn = oneway_merge;
 212         tree = parse_tree_indirect(head_sha1);
 213         if (!tree)
 214                 die("failed to unpack HEAD tree object");
 215         parse_tree(tree);
 216         init_tree_desc(&t, tree->buffer, tree->size);
 217         if (unpack_trees(1, &t, &opts))
 218                 exit(128); /* We've already reported the error, finish dying */
 219 }
 220
 221 static char *prepare_index(int argc, const char **argv, const char *prefix)
 222 {
 223         int fd;
 224         struct string_list partial;
 225         const char **pathspec = NULL;
 226
 227         if (interactive) {
 228                 interactive_add(argc, argv, prefix);
 229                 if (read_cache() < 0)
 230                         die("index file corrupt");
 231                 commit_style = COMMIT_AS_IS;
 232                 return get_index_file();
 233         }
 234
 235         if (read_cache() < 0)
 236                 die("index file corrupt");
 237
 238         if (*argv)
 239                 pathspec = get_pathspec(prefix, argv);
 240
 241         /*
 242          * Non partial, non as-is commit.
 243          *
 244          * (1) get the real index;
 245          * (2) update the_index as necessary;
 246          * (3) write the_index out to the real index (still locked);
 247          * (4) return the name of the locked index file.
 248          *
 249          * The caller should run hooks on the locked real index, and
 250          * (A) if all goes well, commit the real index;
 251          * (B) on failure, rollback the real index.
 252          */
 253         if (all || (also && pathspec && *pathspec)) {
 254                 int fd = hold_locked_index(&index_lock, 1);
 255                 add_files_to_cache(also ? prefix : NULL, pathspec, 0);
 256                 refresh_cache(REFRESH_QUIET);
 257                 if (write_cache(fd, active_cache, active_nr) ||
 258                     close_lock_file(&index_lock))
 259                         die("unable to write new_index file");
 260                 commit_style = COMMIT_NORMAL;
 261                 return index_lock.filename;
 262         }
 263
 264         /*
 265          * As-is commit.
 266          *
 267          * (1) return the name of the real index file.
 268          *
 269          * The caller should run hooks on the real index, and run
 270          * hooks on the real index, and create commit from the_index.
 271          * We still need to refresh the index here.
 272          */
 273         if (!pathspec || !*pathspec) {
 274                 fd = hold_locked_index(&index_lock, 1);
 275                 refresh_cache(REFRESH_QUIET);
 276                 if (write_cache(fd, active_cache, active_nr) ||
 277                     commit_locked_index(&index_lock))
 278                         die("unable to write new_index file");
 279                 commit_style = COMMIT_AS_IS;
 280                 return get_index_file();
 281         }
 282
 283         /*
 284          * A partial commit.
 285          *
 286          * (0) find the set of affected paths;
 287          * (1) get lock on the real index file;
 288          * (2) update the_index with the given paths;
 289          * (3) write the_index out to the real index (still locked);
 290          * (4) get lock on the false index file;
 291          * (5) reset the_index from HEAD;
 292          * (6) update the_index the same way as (2);
 293          * (7) write the_index out to the false index file;
 294          * (8) return the name of the false index file (still locked);
 295          *
 296          * The caller should run hooks on the locked false index, and
 297          * create commit from it.  Then
 298          * (A) if all goes well, commit the real index;
 299          * (B) on failure, rollback the real index;
 300          * In either case, rollback the false index.
 301          */
 302         commit_style = COMMIT_PARTIAL;
 303
 304         if (file_exists(git_path("MERGE_HEAD")))
 305                 die("cannot do a partial commit during a merge.");
 306
 307         memset(&partial, 0, sizeof(partial));
 308         partial.strdup_strings = 1;
 309         if (list_paths(&partial, initial_commit ? NULL : "HEAD", prefix, pathspec))
 310                 exit(1);
 311
 312         discard_cache();
 313         if (read_cache() < 0)
 314                 die("cannot read the index");
 315
 316         fd = hold_locked_index(&index_lock, 1);
 317         add_remove_files(&partial);
 318         refresh_cache(REFRESH_QUIET);
 319         if (write_cache(fd, active_cache, active_nr) ||
 320             close_lock_file(&index_lock))
 321                 die("unable to write new_index file");
 322
 323         fd = hold_lock_file_for_update(&false_lock,
 324                                        git_path("next-index-%d", getpid()), 1);
 325
 326         create_base_index();
 327         add_remove_files(&partial);
 328         refresh_cache(REFRESH_QUIET);
 329
 330         if (write_cache(fd, active_cache, active_nr) ||
 331             close_lock_file(&false_lock))
 332                 die("unable to write temporary index file");
 333
 334         discard_cache();
 335         read_cache_from(false_lock.filename);
 336
 337         return false_lock.filename;
 338 }
 339
 340 static int run_status(FILE *fp, const char *index_file, const char *prefix, int nowarn)
 341 {
 342         struct wt_status s;
 343
 344         wt_status_prepare(&s);
 345         if (wt_status_relative_paths)
 346                 s.prefix = prefix;
 347
 348         if (amend) {
 349                 s.amend = 1;
 350                 s.reference = "HEAD^1";
 351         }
 352         s.verbose = verbose;
 353         s.untracked = (show_untracked_files == SHOW_ALL_UNTRACKED_FILES);
 354         s.index_file = index_file;
 355         s.fp = fp;
 356         s.nowarn = nowarn;
 357
 358         wt_status_print(&s);
 359
 360         return s.commitable;
 361 }
 362
 363 static int run_hook(const char *index_file, const char *name, ...)
 364 {
 365         struct child_process hook;
 366         const char *argv[10], *env[2];
 367         char index[PATH_MAX];
 368         va_list args;
 369         int i;
 370
 371         va_start(args, name);
 372         argv[0] = git_path("hooks/%s", name);
 373         i = 0;
 374         do {
 375                 if (++i >= ARRAY_SIZE(argv))
 376                         die ("run_hook(): too many arguments");
 377                 argv[i] = va_arg(args, const char *);
 378         } while (argv[i]);
 379         va_end(args);
 380
 381         snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 382         env[0] = index;
 383         env[1] = NULL;
 384
 385         if (access(argv[0], X_OK) < 0)
 386                 return 0;
 387
 388         memset(&hook, 0, sizeof(hook));
 389         hook.argv = argv;
 390         hook.no_stdin = 1;
 391         hook.stdout_to_stderr = 1;
 392         hook.env = env;
 393
 394         return run_command(&hook);
 395 }
 396
 397 static int is_a_merge(const unsigned char *sha1)
 398 {
 399         struct commit *commit = lookup_commit(sha1);
 400         if (!commit || parse_commit(commit))
 401                 die("could not parse HEAD commit");
 402         return !!(commit->parents && commit->parents->next);
 403 }
 404
 405 static const char sign_off_header[] = "Signed-off-by: ";
 406
 407 static void determine_author_info(void)
 408 {
 409         char *name, *email, *date;
 410
 411         name = getenv("GIT_AUTHOR_NAME");
 412         email = getenv("GIT_AUTHOR_EMAIL");
 413         date = getenv("GIT_AUTHOR_DATE");
 414
 415         if (use_message) {
 416                 const char *a, *lb, *rb, *eol;
 417
 418                 a = strstr(use_message_buffer, "\nauthor ");
 419                 if (!a)
 420                         die("invalid commit: %s", use_message);
 421
 422                 lb = strstr(a + 8, " <");
 423                 rb = strstr(a + 8, "> ");
 424                 eol = strchr(a + 8, '\n');
 425                 if (!lb || !rb || !eol)
 426                         die("invalid commit: %s", use_message);
 427
 428                 name = xstrndup(a + 8, lb - (a + 8));
 429                 email = xstrndup(lb + 2, rb - (lb + 2));
 430                 date = xstrndup(rb + 2, eol - (rb + 2));
 431         }
 432
 433         if (force_author) {
 434                 const char *lb = strstr(force_author, " <");
 435                 const char *rb = strchr(force_author, '>');
 436
 437                 if (!lb || !rb)
 438                         die("malformed --author parameter");
 439                 name = xstrndup(force_author, lb - force_author);
 440                 email = xstrndup(lb + 2, rb - (lb + 2));
 441         }
 442
 443         author_name = name;
 444         author_email = email;
 445         author_date = date;
 446 }
 447
 448 static int prepare_to_commit(const char *index_file, const char *prefix)
 449 {
 450         struct stat statbuf;
 451         int commitable, saved_color_setting;
 452         struct strbuf sb;
 453         char *buffer;
 454         FILE *fp;
 455         const char *hook_arg1 = NULL;
 456         const char *hook_arg2 = NULL;
 457         int ident_shown = 0;
 458
 459         if (!no_verify && run_hook(index_file, "pre-commit", NULL))
 460                 return 0;
 461
 462         strbuf_init(&sb, 0);
 463         if (message.len) {
 464                 strbuf_addbuf(&sb, &message);
 465                 hook_arg1 = "message";
 466         } else if (logfile && !strcmp(logfile, "-")) {
 467                 if (isatty(0))
 468                         fprintf(stderr, "(reading log message from standard input)\n");
 469                 if (strbuf_read(&sb, 0, 0) < 0)
 470                         die("could not read log from standard input");
 471                 hook_arg1 = "message";
 472         } else if (logfile) {
 473                 if (strbuf_read_file(&sb, logfile, 0) < 0)
 474                         die("could not read log file '%s': %s",
 475                             logfile, strerror(errno));
 476                 hook_arg1 = "message";
 477         } else if (use_message) {
 478                 buffer = strstr(use_message_buffer, "\n\n");
 479                 if (!buffer || buffer[2] == '\0')
 480                         die("commit has empty message");
 481                 strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
 482                 hook_arg1 = "commit";
 483                 hook_arg2 = use_message;
 484         } else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
 485                 if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
 486                         die("could not read MERGE_MSG: %s", strerror(errno));
 487                 hook_arg1 = "merge";
 488         } else if (!stat(git_path("SQUASH_MSG"), &statbuf)) {
 489                 if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
 490                         die("could not read SQUASH_MSG: %s", strerror(errno));
 491                 hook_arg1 = "squash";
 492         } else if (template_file && !stat(template_file, &statbuf)) {
 493                 if (strbuf_read_file(&sb, template_file, 0) < 0)
 494                         die("could not read %s: %s",
 495                             template_file, strerror(errno));
 496                 hook_arg1 = "template";
 497         }
 498
 499         /*
 500          * This final case does not modify the template message,
 501          * it just sets the argument to the prepare-commit-msg hook.
 502          */
 503         else if (in_merge)
 504                 hook_arg1 = "merge";
 505
 506         fp = fopen(git_path(commit_editmsg), "w");
 507         if (fp == NULL)
 508                 die("could not open %s: %s",
 509                     git_path(commit_editmsg), strerror(errno));
 510
 511         if (cleanup_mode != CLEANUP_NONE)
 512                 stripspace(&sb, 0);
 513
 514         if (signoff) {
 515                 struct strbuf sob;
 516                 int i;
 517
 518                 strbuf_init(&sob, 0);
 519                 strbuf_addstr(&sob, sign_off_header);
 520                 strbuf_addstr(&sob, fmt_name(getenv("GIT_COMMITTER_NAME"),
 521                                              getenv("GIT_COMMITTER_EMAIL")));
 522                 strbuf_addch(&sob, '\n');
 523                 for (i = sb.len - 1; i > 0 && sb.buf[i - 1] != '\n'; i--)
 524                         ; /* do nothing */
 525                 if (prefixcmp(sb.buf + i, sob.buf)) {
 526                         if (prefixcmp(sb.buf + i, sign_off_header))
 527                                 strbuf_addch(&sb, '\n');
 528                         strbuf_addbuf(&sb, &sob);
 529                 }
 530                 strbuf_release(&sob);
 531         }
 532
 533         if (fwrite(sb.buf, 1, sb.len, fp) < sb.len)
 534                 die("could not write commit template: %s", strerror(errno));
 535
 536         strbuf_release(&sb);
 537
 538         determine_author_info();
 539
 540         /* This checks if committer ident is explicitly given */
 541         git_committer_info(0);
 542         if (use_editor) {
 543                 char *author_ident;
 544                 const char *committer_ident;
 545
 546                 if (in_merge)
 547                         fprintf(fp,
 548                                 "#\n"
 549                                 "# It looks like you may be committing a MERGE.\n"
 550                                 "# If this is not correct, please remove the file\n"
 551                                 "#      %s\n"
 552                                 "# and try again.\n"
 553                                 "#\n",
 554                                 git_path("MERGE_HEAD"));
 555
 556                 fprintf(fp,
 557                         "\n"
 558                         "# Please enter the commit message for your changes.\n"
 559                         "# (Comment lines starting with '#' will ");
 560                 if (cleanup_mode == CLEANUP_ALL)
 561                         fprintf(fp, "not be included)\n");
 562                 else /* CLEANUP_SPACE, that is. */
 563                         fprintf(fp, "be kept.\n"
 564                                 "# You can remove them yourself if you want to)\n");
 565                 if (only_include_assumed)
 566                         fprintf(fp, "# %s\n", only_include_assumed);
 567
 568                 author_ident = xstrdup(fmt_name(author_name, author_email));
 569                 committer_ident = fmt_name(getenv("GIT_COMMITTER_NAME"),
 570                                            getenv("GIT_COMMITTER_EMAIL"));
 571                 if (strcmp(author_ident, committer_ident))
 572                         fprintf(fp,
 573                                 "%s"
 574                                 "# Author:    %s\n",
 575                                 ident_shown++ ? "" : "#\n",
 576                                 author_ident);
 577                 free(author_ident);
 578
 579                 if (!user_ident_explicitly_given)
 580                         fprintf(fp,
 581                                 "%s"
 582                                 "# Committer: %s\n",
 583                                 ident_shown++ ? "" : "#\n",
 584                                 committer_ident);
 585
 586                 if (ident_shown)
 587                         fprintf(fp, "#\n");
 588
 589                 saved_color_setting = wt_status_use_color;
 590                 wt_status_use_color = 0;
 591                 commitable = run_status(fp, index_file, prefix, 1);
 592                 wt_status_use_color = saved_color_setting;
 593         } else {
 594                 struct rev_info rev;
 595                 unsigned char sha1[20];
 596                 const char *parent = "HEAD";
 597
 598                 if (!active_nr && read_cache() < 0)
 599                         die("Cannot read index");
 600
 601                 if (amend)
 602                         parent = "HEAD^1";
 603
 604                 if (get_sha1(parent, sha1))
 605                         commitable = !!active_nr;
 606                 else {
 607                         init_revisions(&rev, "");
 608                         rev.abbrev = 0;
 609                         setup_revisions(0, NULL, &rev, parent);
 610                         DIFF_OPT_SET(&rev.diffopt, QUIET);
 611                         DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
 612                         run_diff_index(&rev, 1 /* cached */);
 613
 614                         commitable = !!DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES);
 615                 }
 616         }
 617
 618         fclose(fp);
 619
 620         if (!commitable && !in_merge && !allow_empty &&
 621             !(amend && is_a_merge(head_sha1))) {
 622                 run_status(stdout, index_file, prefix, 0);
 623                 unlink(commit_editmsg);
 624                 return 0;
 625         }
 626
 627         /*
 628          * Re-read the index as pre-commit hook could have updated it,
 629          * and write it out as a tree.  We must do this before we invoke
 630          * the editor and after we invoke run_status above.
 631          */
 632         discard_cache();
 633         read_cache_from(index_file);
 634         if (!active_cache_tree)
 635                 active_cache_tree = cache_tree();
 636         if (cache_tree_update(active_cache_tree,
 637                               active_cache, active_nr, 0, 0) < 0) {
 638                 error("Error building trees");
 639                 return 0;
 640         }
 641
 642         if (run_hook(index_file, "prepare-commit-msg",
 643                      git_path(commit_editmsg), hook_arg1, hook_arg2, NULL))
 644                 return 0;
 645
 646         if (use_editor) {
 647                 char index[PATH_MAX];
 648                 const char *env[2] = { index, NULL };
 649                 snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 650                 launch_editor(git_path(commit_editmsg), NULL, env);
 651         }
 652
 653         if (!no_verify &&
 654             run_hook(index_file, "commit-msg", git_path(commit_editmsg), NULL)) {
 655                 return 0;
 656         }
 657
 658         return 1;
 659 }
 660
 661 /*
 662  * Find out if the message starting at position 'start' in the strbuf
 663  * contains only whitespace and Signed-off-by lines.
 664  */
 665 static int message_is_empty(struct strbuf *sb, int start)
 666 {
 667         struct strbuf tmpl;
 668         const char *nl;
 669         int eol, i;
 670
 671         if (cleanup_mode == CLEANUP_NONE && sb->len)
 672                 return 0;
 673
 674         /* See if the template is just a prefix of the message. */
 675         strbuf_init(&tmpl, 0);
 676         if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
 677                 stripspace(&tmpl, cleanup_mode == CLEANUP_ALL);
 678                 if (start + tmpl.len <= sb->len &&
 679                     memcmp(tmpl.buf, sb->buf + start, tmpl.len) == 0)
 680                         start += tmpl.len;
 681         }
 682         strbuf_release(&tmpl);
 683
 684         /* Check if the rest is just whitespace and Signed-of-by's. */
 685         for (i = start; i < sb->len; i++) {
 686                 nl = memchr(sb->buf + i, '\n', sb->len - i);
 687                 if (nl)
 688                         eol = nl - sb->buf;
 689                 else
 690                         eol = sb->len;
 691
 692                 if (strlen(sign_off_header) <= eol - i &&
 693                     !prefixcmp(sb->buf + i, sign_off_header)) {
 694                         i = eol;
 695                         continue;
 696                 }
 697                 while (i < eol)
 698                         if (!isspace(sb->buf[i++]))
 699                                 return 0;
 700         }
 701
 702         return 1;
 703 }
 704
 705 static int parse_and_validate_options(int argc, const char *argv[],
 706                                       const char * const usage[])
 707 {
 708         int f = 0;
 709
 710         argc = parse_options(argc, argv, builtin_commit_options, usage, 0);
 711
 712         if (logfile || message.len || use_message)
 713                 use_editor = 0;
 714         if (edit_flag)
 715                 use_editor = 1;
 716         if (!use_editor)
 717                 setenv("GIT_EDITOR", ":", 1);
 718
 719         if (get_sha1("HEAD", head_sha1))
 720                 initial_commit = 1;
 721
 722         if (!get_sha1("MERGE_HEAD", merge_head_sha1))
 723                 in_merge = 1;
 724
 725         /* Sanity check options */
 726         if (amend && initial_commit)
 727                 die("You have nothing to amend.");
 728         if (amend && in_merge)
 729                 die("You are in the middle of a merge -- cannot amend.");
 730
 731         if (use_message)
 732                 f++;
 733         if (edit_message)
 734                 f++;
 735         if (logfile)
 736                 f++;
 737         if (f > 1)
 738                 die("Only one of -c/-C/-F can be used.");
 739         if (message.len && f > 0)
 740                 die("Option -m cannot be combined with -c/-C/-F.");
 741         if (edit_message)
 742                 use_message = edit_message;
 743         if (amend && !use_message)
 744                 use_message = "HEAD";
 745         if (use_message) {
 746                 unsigned char sha1[20];
 747                 static char utf8[] = "UTF-8";
 748                 const char *out_enc;
 749                 char *enc, *end;
 750                 struct commit *commit;
 751
 752                 if (get_sha1(use_message, sha1))
 753                         die("could not lookup commit %s", use_message);
 754                 commit = lookup_commit_reference(sha1);
 755                 if (!commit || parse_commit(commit))
 756                         die("could not parse commit %s", use_message);
 757
 758                 enc = strstr(commit->buffer, "\nencoding");
 759                 if (enc) {
 760                         end = strchr(enc + 10, '\n');
 761                         enc = xstrndup(enc + 10, end - (enc + 10));
 762                 } else {
 763                         enc = utf8;
 764                 }
 765                 out_enc = git_commit_encoding ? git_commit_encoding : utf8;
 766
 767                 if (strcmp(out_enc, enc))
 768                         use_message_buffer =
 769                                 reencode_string(commit->buffer, out_enc, enc);
 770
 771                 /*
 772                  * If we failed to reencode the buffer, just copy it
 773                  * byte for byte so the user can try to fix it up.
 774                  * This also handles the case where input and output
 775                  * encodings are identical.
 776                  */
 777                 if (use_message_buffer == NULL)
 778                         use_message_buffer = xstrdup(commit->buffer);
 779                 if (enc != utf8)
 780                         free(enc);
 781         }
 782
 783         if (!!also + !!only + !!all + !!interactive > 1)
 784                 die("Only one of --include/--only/--all/--interactive can be used.");
 785         if (argc == 0 && (also || (only && !amend)))
 786                 die("No paths with --include/--only does not make sense.");
 787         if (argc == 0 && only && amend)
 788                 only_include_assumed = "Clever... amending the last one with dirty index.";
 789         if (argc > 0 && !also && !only)
 790                 only_include_assumed = "Explicit paths specified without -i nor -o; assuming --only paths...";
 791         if (!cleanup_arg || !strcmp(cleanup_arg, "default"))
 792                 cleanup_mode = use_editor ? CLEANUP_ALL : CLEANUP_SPACE;
 793         else if (!strcmp(cleanup_arg, "verbatim"))
 794                 cleanup_mode = CLEANUP_NONE;
 795         else if (!strcmp(cleanup_arg, "whitespace"))
 796                 cleanup_mode = CLEANUP_SPACE;
 797         else if (!strcmp(cleanup_arg, "strip"))
 798                 cleanup_mode = CLEANUP_ALL;
 799         else
 800                 die("Invalid cleanup mode %s", cleanup_arg);
 801
 802         if (!untracked_files_arg)
 803                 ; /* default already initialized */
 804         else if (!strcmp(untracked_files_arg, "no"))
 805                 show_untracked_files = SHOW_NO_UNTRACKED_FILES;
 806         else if (!strcmp(untracked_files_arg, "normal"))
 807                 show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
 808         else if (!strcmp(untracked_files_arg, "all"))
 809                 show_untracked_files = SHOW_ALL_UNTRACKED_FILES;
 810         else
 811                 die("Invalid untracked files mode '%s'", untracked_files_arg);
 812
 813         if (all && argc > 0)
 814                 die("Paths with -a does not make sense.");
 815         else if (interactive && argc > 0)
 816                 die("Paths with --interactive does not make sense.");
 817
 818         return argc;
 819 }
 820
 821 int cmd_status(int argc, const char **argv, const char *prefix)
 822 {
 823         const char *index_file;
 824         int commitable;
 825
 826         git_config(git_status_config, NULL);
 827
 828         if (wt_status_use_color == -1)
 829                 wt_status_use_color = git_use_color_default;
 830
 831         argc = parse_and_validate_options(argc, argv, builtin_status_usage);
 832
 833         index_file = prepare_index(argc, argv, prefix);
 834
 835         commitable = run_status(stdout, index_file, prefix, 0);
 836
 837         rollback_index_files();
 838
 839         return commitable ? 0 : 1;
 840 }
 841
 842 static void print_summary(const char *prefix, const unsigned char *sha1)
 843 {
 844         struct rev_info rev;
 845         struct commit *commit;
 846
 847         commit = lookup_commit(sha1);
 848         if (!commit)
 849                 die("couldn't look up newly created commit");
 850         if (!commit || parse_commit(commit))
 851                 die("could not parse newly created commit");
 852
 853         init_revisions(&rev, prefix);
 854         setup_revisions(0, NULL, &rev, NULL);
 855
 856         rev.abbrev = 0;
 857         rev.diff = 1;
 858         rev.diffopt.output_format =
 859                 DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
 860
 861         rev.verbose_header = 1;
 862         rev.show_root_diff = 1;
 863         get_commit_format("format:%h: %s", &rev);
 864         rev.always_show_header = 0;
 865         rev.diffopt.detect_rename = 1;
 866         rev.diffopt.rename_limit = 100;
 867         rev.diffopt.break_opt = 0;
 868         diff_setup_done(&rev.diffopt);
 869
 870         printf("Created %scommit ", initial_commit ? "initial " : "");
 871
 872         if (!log_tree_commit(&rev, commit)) {
 873                 struct strbuf buf = STRBUF_INIT;
 874                 format_commit_message(commit, "%h: %s", &buf);
 875                 printf("%s\n", buf.buf);
 876                 strbuf_release(&buf);
 877         }
 878 }
 879
 880 int git_commit_config(const char *k, const char *v, void *cb)
 881 {
 882         if (!strcmp(k, "commit.template"))
 883                 return git_config_string(&template_file, k, v);
 884
 885         return git_status_config(k, v, cb);
 886 }
 887
 888 static const char commit_utf8_warn[] =
 889 "Warning: commit message does not conform to UTF-8.\n"
 890 "You may want to amend it after fixing the message, or set the config\n"
 891 "variable i18n.commitencoding to the encoding your project uses.\n";
 892
 893 static void add_parent(struct strbuf *sb, const unsigned char *sha1)
 894 {
 895         struct object *obj = parse_object(sha1);
 896         const char *parent = sha1_to_hex(sha1);
 897         const char *cp;
 898
 899         if (!obj)
 900                 die("Unable to find commit parent %s", parent);
 901         if (obj->type != OBJ_COMMIT)
 902                 die("Parent %s isn't a proper commit", parent);
 903
 904         for (cp = sb->buf; cp && (cp = strstr(cp, "\nparent ")); cp += 8) {
 905                 if (!memcmp(cp + 8, parent, 40) && cp[48] == '\n') {
 906                         error("duplicate parent %s ignored", parent);
 907                         return;
 908                 }
 909         }
 910         strbuf_addf(sb, "parent %s\n", parent);
 911 }
 912
 913 int cmd_commit(int argc, const char **argv, const char *prefix)
 914 {
 915         int header_len;
 916         struct strbuf sb;
 917         const char *index_file, *reflog_msg;
 918         char *nl, *p;
 919         unsigned char commit_sha1[20];
 920         struct ref_lock *ref_lock;
 921
 922         git_config(git_commit_config, NULL);
 923
 924         argc = parse_and_validate_options(argc, argv, builtin_commit_usage);
 925
 926         index_file = prepare_index(argc, argv, prefix);
 927
 928         /* Set up everything for writing the commit object.  This includes
 929            running hooks, writing the trees, and interacting with the user.  */
 930         if (!prepare_to_commit(index_file, prefix)) {
 931                 rollback_index_files();
 932                 return 1;
 933         }
 934
 935         /*
 936          * The commit object
 937          */
 938         strbuf_init(&sb, 0);
 939         strbuf_addf(&sb, "tree %s\n",
 940                     sha1_to_hex(active_cache_tree->sha1));
 941
 942         /* Determine parents */
 943         if (initial_commit) {
 944                 reflog_msg = "commit (initial)";
 945         } else if (amend) {
 946                 struct commit_list *c;
 947                 struct commit *commit;
 948
 949                 reflog_msg = "commit (amend)";
 950                 commit = lookup_commit(head_sha1);
 951                 if (!commit || parse_commit(commit))
 952                         die("could not parse HEAD commit");
 953
 954                 for (c = commit->parents; c; c = c->next)
 955                         add_parent(&sb, c->item->object.sha1);
 956         } else if (in_merge) {
 957                 struct strbuf m;
 958                 FILE *fp;
 959
 960                 reflog_msg = "commit (merge)";
 961                 add_parent(&sb, head_sha1);
 962                 strbuf_init(&m, 0);
 963                 fp = fopen(git_path("MERGE_HEAD"), "r");
 964                 if (fp == NULL)
 965                         die("could not open %s for reading: %s",
 966                             git_path("MERGE_HEAD"), strerror(errno));
 967                 while (strbuf_getline(&m, fp, '\n') != EOF) {
 968                         unsigned char sha1[20];
 969                         if (get_sha1_hex(m.buf, sha1) < 0)
 970                                 die("Corrupt MERGE_HEAD file (%s)", m.buf);
 971                         add_parent(&sb, sha1);
 972                 }
 973                 fclose(fp);
 974                 strbuf_release(&m);
 975         } else {
 976                 reflog_msg = "commit";
 977                 strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
 978         }
 979
 980         strbuf_addf(&sb, "author %s\n",
 981                     fmt_ident(author_name, author_email, author_date, IDENT_ERROR_ON_NO_NAME));
 982         strbuf_addf(&sb, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
 983         if (!is_encoding_utf8(git_commit_encoding))
 984                 strbuf_addf(&sb, "encoding %s\n", git_commit_encoding);
 985         strbuf_addch(&sb, '\n');
 986
 987         /* Finally, get the commit message */
 988         header_len = sb.len;
 989         if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
 990                 rollback_index_files();
 991                 die("could not read commit message");
 992         }
 993
 994         /* Truncate the message just before the diff, if any. */
 995         p = strstr(sb.buf, "\ndiff --git a/");
 996         if (p != NULL)
 997                 strbuf_setlen(&sb, p - sb.buf + 1);
 998
 999         if (cleanup_mode != CLEANUP_NONE)
1000                 stripspace(&sb, cleanup_mode == CLEANUP_ALL);
1001         if (sb.len < header_len || message_is_empty(&sb, header_len)) {
1002                 rollback_index_files();
1003                 die("no commit message?  aborting commit.");
1004         }
1005         strbuf_addch(&sb, '\0');
1006         if (is_encoding_utf8(git_commit_encoding) && !is_utf8(sb.buf))
1007                 fprintf(stderr, commit_utf8_warn);
1008
1009         if (write_sha1_file(sb.buf, sb.len - 1, commit_type, commit_sha1)) {
1010                 rollback_index_files();
1011                 die("failed to write commit object");
1012         }
1013
1014         ref_lock = lock_any_ref_for_update("HEAD",
1015                                            initial_commit ? NULL : head_sha1,
1016                                            0);
1017
1018         nl = strchr(sb.buf + header_len, '\n');
1019         if (nl)
1020                 strbuf_setlen(&sb, nl + 1 - sb.buf);
1021         else
1022                 strbuf_addch(&sb, '\n');
1023         strbuf_remove(&sb, 0, header_len);
1024         strbuf_insert(&sb, 0, reflog_msg, strlen(reflog_msg));
1025         strbuf_insert(&sb, strlen(reflog_msg), ": ", 2);
1026
1027         if (!ref_lock) {
1028                 rollback_index_files();
1029                 die("cannot lock HEAD ref");
1030         }
1031         if (write_ref_sha1(ref_lock, commit_sha1, sb.buf) < 0) {
1032                 rollback_index_files();
1033                 die("cannot update HEAD ref");
1034         }
1035
1036         unlink(git_path("MERGE_HEAD"));
1037         unlink(git_path("MERGE_MSG"));
1038         unlink(git_path("SQUASH_MSG"));
1039
1040         if (commit_index_files())
1041                 die ("Repository has been updated, but unable to write\n"
1042                      "new_index file. Check that disk is not full or quota is\n"
1043                      "not exceeded, and then \"git reset HEAD\" to recover.");
1044
1045         rerere();
1046         run_hook(get_index_file(), "post-commit", NULL);
1047         if (!quiet)
1048                 print_summary(prefix, commit_sha1);
1049
1050         return 0;
1051 }