git.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "exec_cmd.h"
   4 #include "help.h"
   5 #include "quote.h"
   6 #include "run-command.h"
   7 #include "commit.h"
   8
   9 const char git_usage_string[] =
  10         "git [--version] [--help] [-C <path>] [-c name=value]\n"
  11         "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  12         "           [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]\n"
  13         "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  14         "           <command> [<args>]";
  15
  16 const char git_more_info_string[] =
  17         N_("'git help -a' and 'git help -g' lists available subcommands and some\n"
  18            "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  19            "to read about a specific subcommand or concept.");
  20
  21 static struct startup_info git_startup_info;
  22 static int use_pager = -1;
  23
  24 static void commit_pager_choice(void) {
  25         switch (use_pager) {
  26         case 0:
  27                 setenv("GIT_PAGER", "cat", 1);
  28                 break;
  29         case 1:
  30                 setup_pager();
  31                 break;
  32         default:
  33                 break;
  34         }
  35 }
  36
  37 static int handle_options(const char ***argv, int *argc, int *envchanged)
  38 {
  39         const char **orig_argv = *argv;
  40
  41         while (*argc > 0) {
  42                 const char *cmd = (*argv)[0];
  43                 if (cmd[0] != '-')
  44                         break;
  45
  46                 /*
  47                  * For legacy reasons, the "version" and "help"
  48                  * commands can be written with "--" prepended
  49                  * to make them look like flags.
  50                  */
  51                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  52                         break;
  53
  54                 /*
  55                  * Check remaining flags.
  56                  */
  57                 if (starts_with(cmd, "--exec-path")) {
  58                         cmd += 11;
  59                         if (*cmd == '=')
  60                                 git_set_argv_exec_path(cmd + 1);
  61                         else {
  62                                 puts(git_exec_path());
  63                                 exit(0);
  64                         }
  65                 } else if (!strcmp(cmd, "--html-path")) {
  66                         puts(system_path(GIT_HTML_PATH));
  67                         exit(0);
  68                 } else if (!strcmp(cmd, "--man-path")) {
  69                         puts(system_path(GIT_MAN_PATH));
  70                         exit(0);
  71                 } else if (!strcmp(cmd, "--info-path")) {
  72                         puts(system_path(GIT_INFO_PATH));
  73                         exit(0);
  74                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  75                         use_pager = 1;
  76                 } else if (!strcmp(cmd, "--no-pager")) {
  77                         use_pager = 0;
  78                         if (envchanged)
  79                                 *envchanged = 1;
  80                 } else if (!strcmp(cmd, "--no-replace-objects")) {
  81                         check_replace_refs = 0;
  82                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
  83                         if (envchanged)
  84                                 *envchanged = 1;
  85                 } else if (!strcmp(cmd, "--git-dir")) {
  86                         if (*argc < 2) {
  87                                 fprintf(stderr, "No directory given for --git-dir.\n" );
  88                                 usage(git_usage_string);
  89                         }
  90                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
  91                         if (envchanged)
  92                                 *envchanged = 1;
  93                         (*argv)++;
  94                         (*argc)--;
  95                 } else if (starts_with(cmd, "--git-dir=")) {
  96                         setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
  97                         if (envchanged)
  98                                 *envchanged = 1;
  99                 } else if (!strcmp(cmd, "--namespace")) {
 100                         if (*argc < 2) {
 101                                 fprintf(stderr, "No namespace given for --namespace.\n" );
 102                                 usage(git_usage_string);
 103                         }
 104                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 105                         if (envchanged)
 106                                 *envchanged = 1;
 107                         (*argv)++;
 108                         (*argc)--;
 109                 } else if (starts_with(cmd, "--namespace=")) {
 110                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd + 12, 1);
 111                         if (envchanged)
 112                                 *envchanged = 1;
 113                 } else if (!strcmp(cmd, "--work-tree")) {
 114                         if (*argc < 2) {
 115                                 fprintf(stderr, "No directory given for --work-tree.\n" );
 116                                 usage(git_usage_string);
 117                         }
 118                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 119                         if (envchanged)
 120                                 *envchanged = 1;
 121                         (*argv)++;
 122                         (*argc)--;
 123                 } else if (starts_with(cmd, "--work-tree=")) {
 124                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 125                         if (envchanged)
 126                                 *envchanged = 1;
 127                 } else if (!strcmp(cmd, "--bare")) {
 128                         char *cwd = xgetcwd();
 129                         is_bare_repository_cfg = 1;
 130                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 131                         free(cwd);
 132                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 133                         if (envchanged)
 134                                 *envchanged = 1;
 135                 } else if (!strcmp(cmd, "-c")) {
 136                         if (*argc < 2) {
 137                                 fprintf(stderr, "-c expects a configuration string\n" );
 138                                 usage(git_usage_string);
 139                         }
 140                         git_config_push_parameter((*argv)[1]);
 141                         (*argv)++;
 142                         (*argc)--;
 143                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
 144                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 145                         if (envchanged)
 146                                 *envchanged = 1;
 147                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 148                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 149                         if (envchanged)
 150                                 *envchanged = 1;
 151                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
 152                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 153                         if (envchanged)
 154                                 *envchanged = 1;
 155                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 156                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 157                         if (envchanged)
 158                                 *envchanged = 1;
 159                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
 160                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 161                         if (envchanged)
 162                                 *envchanged = 1;
 163                 } else if (!strcmp(cmd, "--shallow-file")) {
 164                         (*argv)++;
 165                         (*argc)--;
 166                         set_alternate_shallow_file((*argv)[0], 1);
 167                         if (envchanged)
 168                                 *envchanged = 1;
 169                 } else if (!strcmp(cmd, "-C")) {
 170                         if (*argc < 2) {
 171                                 fprintf(stderr, "No directory given for -C.\n" );
 172                                 usage(git_usage_string);
 173                         }
 174                         if (chdir((*argv)[1]))
 175                                 die_errno("Cannot change to '%s'", (*argv)[1]);
 176                         if (envchanged)
 177                                 *envchanged = 1;
 178                         (*argv)++;
 179                         (*argc)--;
 180                 } else {
 181                         fprintf(stderr, "Unknown option: %s\n", cmd);
 182                         usage(git_usage_string);
 183                 }
 184
 185                 (*argv)++;
 186                 (*argc)--;
 187         }
 188         return (*argv) - orig_argv;
 189 }
 190
 191 static int handle_alias(int *argcp, const char ***argv)
 192 {
 193         int envchanged = 0, ret = 0, saved_errno = errno;
 194         const char *subdir;
 195         int count, option_count;
 196         const char **new_argv;
 197         const char *alias_command;
 198         char *alias_string;
 199         int unused_nongit;
 200
 201         subdir = setup_git_directory_gently(&unused_nongit);
 202
 203         alias_command = (*argv)[0];
 204         alias_string = alias_lookup(alias_command);
 205         if (alias_string) {
 206                 if (alias_string[0] == '!') {
 207                         const char **alias_argv;
 208                         int argc = *argcp, i;
 209
 210                         commit_pager_choice();
 211
 212                         /* build alias_argv */
 213                         alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
 214                         alias_argv[0] = alias_string + 1;
 215                         for (i = 1; i < argc; ++i)
 216                                 alias_argv[i] = (*argv)[i];
 217                         alias_argv[argc] = NULL;
 218
 219                         ret = run_command_v_opt(alias_argv, RUN_USING_SHELL);
 220                         if (ret >= 0)   /* normal exit */
 221                                 exit(ret);
 222
 223                         die_errno("While expanding alias '%s': '%s'",
 224                             alias_command, alias_string + 1);
 225                 }
 226                 count = split_cmdline(alias_string, &new_argv);
 227                 if (count < 0)
 228                         die("Bad alias.%s string: %s", alias_command,
 229                             split_cmdline_strerror(count));
 230                 option_count = handle_options(&new_argv, &count, &envchanged);
 231                 if (envchanged)
 232                         die("alias '%s' changes environment variables\n"
 233                                  "You can use '!git' in the alias to do this.",
 234                                  alias_command);
 235                 memmove(new_argv - option_count, new_argv,
 236                                 count * sizeof(char *));
 237                 new_argv -= option_count;
 238
 239                 if (count < 1)
 240                         die("empty alias for %s", alias_command);
 241
 242                 if (!strcmp(alias_command, new_argv[0]))
 243                         die("recursive alias: %s", alias_command);
 244
 245                 trace_argv_printf(new_argv,
 246                                   "trace: alias expansion: %s =>",
 247                                   alias_command);
 248
 249                 new_argv = xrealloc(new_argv, sizeof(char *) *
 250                                     (count + *argcp));
 251                 /* insert after command name */
 252                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 253
 254                 *argv = new_argv;
 255                 *argcp += count - 1;
 256
 257                 ret = 1;
 258         }
 259
 260         if (subdir && chdir(subdir))
 261                 die_errno("Cannot change to '%s'", subdir);
 262
 263         errno = saved_errno;
 264
 265         return ret;
 266 }
 267
 268 #define RUN_SETUP               (1<<0)
 269 #define RUN_SETUP_GENTLY        (1<<1)
 270 #define USE_PAGER               (1<<2)
 271 /*
 272  * require working tree to be present -- anything uses this needs
 273  * RUN_SETUP for reading from the configuration file.
 274  */
 275 #define NEED_WORK_TREE          (1<<3)
 276
 277 struct cmd_struct {
 278         const char *cmd;
 279         int (*fn)(int, const char **, const char *);
 280         int option;
 281 };
 282
 283 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 284 {
 285         int status, help;
 286         struct stat st;
 287         const char *prefix;
 288
 289         prefix = NULL;
 290         help = argc == 2 && !strcmp(argv[1], "-h");
 291         if (!help) {
 292                 if (p->option & RUN_SETUP)
 293                         prefix = setup_git_directory();
 294                 if (p->option & RUN_SETUP_GENTLY) {
 295                         int nongit_ok;
 296                         prefix = setup_git_directory_gently(&nongit_ok);
 297                 }
 298
 299                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
 300                         use_pager = check_pager_config(p->cmd);
 301                 if (use_pager == -1 && p->option & USE_PAGER)
 302                         use_pager = 1;
 303
 304                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 305                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 306                         trace_repo_setup(prefix);
 307         }
 308         commit_pager_choice();
 309
 310         if (!help && p->option & NEED_WORK_TREE)
 311                 setup_work_tree();
 312
 313         trace_argv_printf(argv, "trace: built-in: git");
 314
 315         status = p->fn(argc, argv, prefix);
 316         if (status)
 317                 return status;
 318
 319         /* Somebody closed stdout? */
 320         if (fstat(fileno(stdout), &st))
 321                 return 0;
 322         /* Ignore write errors for pipes and sockets.. */
 323         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 324                 return 0;
 325
 326         /* Check for ENOSPC and EIO errors.. */
 327         if (fflush(stdout))
 328                 die_errno("write failure on standard output");
 329         if (ferror(stdout))
 330                 die("unknown write failure on standard output");
 331         if (fclose(stdout))
 332                 die_errno("close failed on standard output");
 333         return 0;
 334 }
 335
 336 static struct cmd_struct commands[] = {
 337         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 338         { "annotate", cmd_annotate, RUN_SETUP },
 339         { "apply", cmd_apply, RUN_SETUP_GENTLY },
 340         { "archive", cmd_archive },
 341         { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 342         { "blame", cmd_blame, RUN_SETUP },
 343         { "branch", cmd_branch, RUN_SETUP },
 344         { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 345         { "cat-file", cmd_cat_file, RUN_SETUP },
 346         { "check-attr", cmd_check_attr, RUN_SETUP },
 347         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 348         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 349         { "check-ref-format", cmd_check_ref_format },
 350         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 351         { "checkout-index", cmd_checkout_index,
 352                 RUN_SETUP | NEED_WORK_TREE},
 353         { "cherry", cmd_cherry, RUN_SETUP },
 354         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 355         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 356         { "clone", cmd_clone },
 357         { "column", cmd_column, RUN_SETUP_GENTLY },
 358         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 359         { "commit-tree", cmd_commit_tree, RUN_SETUP },
 360         { "config", cmd_config, RUN_SETUP_GENTLY },
 361         { "count-objects", cmd_count_objects, RUN_SETUP },
 362         { "credential", cmd_credential, RUN_SETUP_GENTLY },
 363         { "describe", cmd_describe, RUN_SETUP },
 364         { "diff", cmd_diff },
 365         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 366         { "diff-index", cmd_diff_index, RUN_SETUP },
 367         { "diff-tree", cmd_diff_tree, RUN_SETUP },
 368         { "fast-export", cmd_fast_export, RUN_SETUP },
 369         { "fetch", cmd_fetch, RUN_SETUP },
 370         { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 371         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 372         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 373         { "format-patch", cmd_format_patch, RUN_SETUP },
 374         { "fsck", cmd_fsck, RUN_SETUP },
 375         { "fsck-objects", cmd_fsck, RUN_SETUP },
 376         { "gc", cmd_gc, RUN_SETUP },
 377         { "get-tar-commit-id", cmd_get_tar_commit_id },
 378         { "grep", cmd_grep, RUN_SETUP_GENTLY },
 379         { "hash-object", cmd_hash_object },
 380         { "help", cmd_help },
 381         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
 382         { "init", cmd_init_db },
 383         { "init-db", cmd_init_db },
 384         { "log", cmd_log, RUN_SETUP },
 385         { "ls-files", cmd_ls_files, RUN_SETUP },
 386         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 387         { "ls-tree", cmd_ls_tree, RUN_SETUP },
 388         { "mailinfo", cmd_mailinfo },
 389         { "mailsplit", cmd_mailsplit },
 390         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 391         { "merge-base", cmd_merge_base, RUN_SETUP },
 392         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 393         { "merge-index", cmd_merge_index, RUN_SETUP },
 394         { "merge-ours", cmd_merge_ours, RUN_SETUP },
 395         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 396         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 397         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 398         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 399         { "merge-tree", cmd_merge_tree, RUN_SETUP },
 400         { "mktag", cmd_mktag, RUN_SETUP },
 401         { "mktree", cmd_mktree, RUN_SETUP },
 402         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 403         { "name-rev", cmd_name_rev, RUN_SETUP },
 404         { "notes", cmd_notes, RUN_SETUP },
 405         { "pack-objects", cmd_pack_objects, RUN_SETUP },
 406         { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
 407         { "pack-refs", cmd_pack_refs, RUN_SETUP },
 408         { "patch-id", cmd_patch_id },
 409         { "pickaxe", cmd_blame, RUN_SETUP },
 410         { "prune", cmd_prune, RUN_SETUP },
 411         { "prune-packed", cmd_prune_packed, RUN_SETUP },
 412         { "push", cmd_push, RUN_SETUP },
 413         { "read-tree", cmd_read_tree, RUN_SETUP },
 414         { "receive-pack", cmd_receive_pack },
 415         { "reflog", cmd_reflog, RUN_SETUP },
 416         { "remote", cmd_remote, RUN_SETUP },
 417         { "remote-ext", cmd_remote_ext },
 418         { "remote-fd", cmd_remote_fd },
 419         { "repack", cmd_repack, RUN_SETUP },
 420         { "replace", cmd_replace, RUN_SETUP },
 421         { "rerere", cmd_rerere, RUN_SETUP },
 422         { "reset", cmd_reset, RUN_SETUP },
 423         { "rev-list", cmd_rev_list, RUN_SETUP },
 424         { "rev-parse", cmd_rev_parse },
 425         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 426         { "rm", cmd_rm, RUN_SETUP },
 427         { "send-pack", cmd_send_pack, RUN_SETUP },
 428         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 429         { "show", cmd_show, RUN_SETUP },
 430         { "show-branch", cmd_show_branch, RUN_SETUP },
 431         { "show-ref", cmd_show_ref, RUN_SETUP },
 432         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 433         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 434         { "stripspace", cmd_stripspace },
 435         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 436         { "tag", cmd_tag, RUN_SETUP },
 437         { "unpack-file", cmd_unpack_file, RUN_SETUP },
 438         { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 439         { "update-index", cmd_update_index, RUN_SETUP },
 440         { "update-ref", cmd_update_ref, RUN_SETUP },
 441         { "update-server-info", cmd_update_server_info, RUN_SETUP },
 442         { "upload-archive", cmd_upload_archive },
 443         { "upload-archive--writer", cmd_upload_archive_writer },
 444         { "var", cmd_var, RUN_SETUP_GENTLY },
 445         { "verify-pack", cmd_verify_pack },
 446         { "verify-tag", cmd_verify_tag, RUN_SETUP },
 447         { "version", cmd_version },
 448         { "whatchanged", cmd_whatchanged, RUN_SETUP },
 449         { "write-tree", cmd_write_tree, RUN_SETUP },
 450 };
 451
 452 int is_builtin(const char *s)
 453 {
 454         int i;
 455         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 456                 struct cmd_struct *p = commands+i;
 457                 if (!strcmp(s, p->cmd))
 458                         return 1;
 459         }
 460         return 0;
 461 }
 462
 463 static void handle_builtin(int argc, const char **argv)
 464 {
 465         const char *cmd = argv[0];
 466         int i;
 467         static const char ext[] = STRIP_EXTENSION;
 468
 469         if (sizeof(ext) > 1) {
 470                 i = strlen(argv[0]) - strlen(ext);
 471                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 472                         char *argv0 = xstrdup(argv[0]);
 473                         argv[0] = cmd = argv0;
 474                         argv0[i] = '\0';
 475                 }
 476         }
 477
 478         /* Turn "git cmd --help" into "git help cmd" */
 479         if (argc > 1 && !strcmp(argv[1], "--help")) {
 480                 argv[1] = argv[0];
 481                 argv[0] = cmd = "help";
 482         }
 483
 484         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 485                 struct cmd_struct *p = commands+i;
 486                 if (strcmp(p->cmd, cmd))
 487                         continue;
 488                 exit(run_builtin(p, argc, argv));
 489         }
 490 }
 491
 492 static void execv_dashed_external(const char **argv)
 493 {
 494         struct strbuf cmd = STRBUF_INIT;
 495         const char *tmp;
 496         int status;
 497
 498         if (use_pager == -1)
 499                 use_pager = check_pager_config(argv[0]);
 500         commit_pager_choice();
 501
 502         strbuf_addf(&cmd, "git-%s", argv[0]);
 503
 504         /*
 505          * argv[0] must be the git command, but the argv array
 506          * belongs to the caller, and may be reused in
 507          * subsequent loop iterations. Save argv[0] and
 508          * restore it on error.
 509          */
 510         tmp = argv[0];
 511         argv[0] = cmd.buf;
 512
 513         trace_argv_printf(argv, "trace: exec:");
 514
 515         /*
 516          * if we fail because the command is not found, it is
 517          * OK to return. Otherwise, we just pass along the status code.
 518          */
 519         status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE | RUN_CLEAN_ON_EXIT);
 520         if (status >= 0 || errno != ENOENT)
 521                 exit(status);
 522
 523         argv[0] = tmp;
 524
 525         strbuf_release(&cmd);
 526 }
 527
 528 static int run_argv(int *argcp, const char ***argv)
 529 {
 530         int done_alias = 0;
 531
 532         while (1) {
 533                 /* See if it's a builtin */
 534                 handle_builtin(*argcp, *argv);
 535
 536                 /* .. then try the external ones */
 537                 execv_dashed_external(*argv);
 538
 539                 /* It could be an alias -- this works around the insanity
 540                  * of overriding "git log" with "git show" by having
 541                  * alias.log = show
 542                  */
 543                 if (done_alias || !handle_alias(argcp, argv))
 544                         break;
 545                 done_alias = 1;
 546         }
 547
 548         return done_alias;
 549 }
 550
 551
 552 int main(int argc, char **av)
 553 {
 554         const char **argv = (const char **) av;
 555         const char *cmd;
 556
 557         startup_info = &git_startup_info;
 558
 559         cmd = git_extract_argv0_path(argv[0]);
 560         if (!cmd)
 561                 cmd = "git-help";
 562
 563         /*
 564          * Always open file descriptors 0/1/2 to avoid clobbering files
 565          * in die().  It also avoids messing up when the pipes are dup'ed
 566          * onto stdin/stdout/stderr in the child processes we spawn.
 567          */
 568         sanitize_stdfds();
 569
 570         git_setup_gettext();
 571
 572         /*
 573          * "git-xxxx" is the same as "git xxxx", but we obviously:
 574          *
 575          *  - cannot take flags in between the "git" and the "xxxx".
 576          *  - cannot execute it externally (since it would just do
 577          *    the same thing over again)
 578          *
 579          * So we just directly call the builtin handler, and die if
 580          * that one cannot handle it.
 581          */
 582         if (starts_with(cmd, "git-")) {
 583                 cmd += 4;
 584                 argv[0] = cmd;
 585                 handle_builtin(argc, argv);
 586                 die("cannot handle %s as a builtin", cmd);
 587         }
 588
 589         /* Look for flags.. */
 590         argv++;
 591         argc--;
 592         handle_options(&argv, &argc, NULL);
 593         if (argc > 0) {
 594                 if (starts_with(argv[0], "--"))
 595                         argv[0] += 2;
 596         } else {
 597                 /* The user didn't specify a command; give them help */
 598                 commit_pager_choice();
 599                 printf("usage: %s\n\n", git_usage_string);
 600                 list_common_cmds_help();
 601                 printf("\n%s\n", _(git_more_info_string));
 602                 exit(1);
 603         }
 604         cmd = argv[0];
 605
 606         /*
 607          * We use PATH to find git commands, but we prepend some higher
 608          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 609          * environment, and the $(gitexecdir) from the Makefile at build
 610          * time.
 611          */
 612         setup_path();
 613
 614         while (1) {
 615                 static int done_help = 0;
 616                 static int was_alias = 0;
 617                 was_alias = run_argv(&argc, &argv);
 618                 if (errno != ENOENT)
 619                         break;
 620                 if (was_alias) {
 621                         fprintf(stderr, "Expansion of alias '%s' failed; "
 622                                 "'%s' is not a git command\n",
 623                                 cmd, argv[0]);
 624                         exit(1);
 625                 }
 626                 if (!done_help) {
 627                         cmd = argv[0] = help_unknown_cmd(cmd);
 628                         done_help = 1;
 629                 } else
 630                         break;
 631         }
 632
 633         fprintf(stderr, "Failed to run command '%s': %s\n",
 634                 cmd, strerror(errno));
 635
 636         return 1;
 637 }