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