git.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "exec-cmd.h"
   4 #include "help.h"
   5 #include "run-command.h"
   6 #include "alias.h"
   7 #include "shallow.h"
   8
   9 #define RUN_SETUP               (1<<0)
  10 #define RUN_SETUP_GENTLY        (1<<1)
  11 #define USE_PAGER               (1<<2)
  12 /*
  13  * require working tree to be present -- anything uses this needs
  14  * RUN_SETUP for reading from the configuration file.
  15  */
  16 #define NEED_WORK_TREE          (1<<3)
  17 #define DELAY_PAGER_CONFIG      (1<<4)
  18 #define NO_PARSEOPT             (1<<5) /* parse-options is not used */
  19
  20 struct cmd_struct {
  21         const char *cmd;
  22         int (*fn)(int, const char **, const char *);
  23         unsigned int option;
  24 };
  25
  26 const char git_usage_string[] =
  27         N_("git [-v | --version] [-h | --help] [-C <path>] [-c <name>=<value>]\n"
  28            "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  29            "           [-p | --paginate | -P | --no-pager] [--no-replace-objects] [--bare]\n"
  30            "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  31            "           [--config-env=<name>=<envvar>] <command> [<args>]");
  32
  33 const char git_more_info_string[] =
  34         N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  35            "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  36            "to read about a specific subcommand or concept.\n"
  37            "See 'git help git' for an overview of the system.");
  38
  39 static int use_pager = -1;
  40
  41 static void list_builtins(struct string_list *list, unsigned int exclude_option);
  42
  43 static void exclude_helpers_from_list(struct string_list *list)
  44 {
  45         int i = 0;
  46
  47         while (i < list->nr) {
  48                 if (strstr(list->items[i].string, "--"))
  49                         unsorted_string_list_delete_item(list, i, 0);
  50                 else
  51                         i++;
  52         }
  53 }
  54
  55 static int match_token(const char *spec, int len, const char *token)
  56 {
  57         int token_len = strlen(token);
  58
  59         return len == token_len && !strncmp(spec, token, token_len);
  60 }
  61
  62 static int list_cmds(const char *spec)
  63 {
  64         struct string_list list = STRING_LIST_INIT_DUP;
  65         int i;
  66         int nongit;
  67
  68         /*
  69         * Set up the repository so we can pick up any repo-level config (like
  70         * completion.commands).
  71         */
  72         setup_git_directory_gently(&nongit);
  73
  74         while (*spec) {
  75                 const char *sep = strchrnul(spec, ',');
  76                 int len = sep - spec;
  77
  78                 if (match_token(spec, len, "builtins"))
  79                         list_builtins(&list, 0);
  80                 else if (match_token(spec, len, "main"))
  81                         list_all_main_cmds(&list);
  82                 else if (match_token(spec, len, "others"))
  83                         list_all_other_cmds(&list);
  84                 else if (match_token(spec, len, "nohelpers"))
  85                         exclude_helpers_from_list(&list);
  86                 else if (match_token(spec, len, "alias"))
  87                         list_aliases(&list);
  88                 else if (match_token(spec, len, "config"))
  89                         list_cmds_by_config(&list);
  90                 else if (len > 5 && !strncmp(spec, "list-", 5)) {
  91                         struct strbuf sb = STRBUF_INIT;
  92
  93                         strbuf_add(&sb, spec + 5, len - 5);
  94                         list_cmds_by_category(&list, sb.buf);
  95                         strbuf_release(&sb);
  96                 }
  97                 else
  98                         die(_("unsupported command listing type '%s'"), spec);
  99                 spec += len;
 100                 if (*spec == ',')
 101                         spec++;
 102         }
 103         for (i = 0; i < list.nr; i++)
 104                 puts(list.items[i].string);
 105         string_list_clear(&list, 0);
 106         return 0;
 107 }
 108
 109 static void commit_pager_choice(void)
 110 {
 111         switch (use_pager) {
 112         case 0:
 113                 setenv("GIT_PAGER", "cat", 1);
 114                 break;
 115         case 1:
 116                 setup_pager();
 117                 break;
 118         default:
 119                 break;
 120         }
 121 }
 122
 123 void setup_auto_pager(const char *cmd, int def)
 124 {
 125         if (use_pager != -1 || pager_in_use())
 126                 return;
 127         use_pager = check_pager_config(cmd);
 128         if (use_pager == -1)
 129                 use_pager = def;
 130         commit_pager_choice();
 131 }
 132
 133 static int handle_options(const char ***argv, int *argc, int *envchanged)
 134 {
 135         const char **orig_argv = *argv;
 136
 137         while (*argc > 0) {
 138                 const char *cmd = (*argv)[0];
 139                 if (cmd[0] != '-')
 140                         break;
 141
 142                 /*
 143                  * For legacy reasons, the "version" and "help"
 144                  * commands can be written with "--" prepended
 145                  * to make them look like flags.
 146                  */
 147                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h") ||
 148                     !strcmp(cmd, "--version") || !strcmp(cmd, "-v"))
 149                         break;
 150
 151                 /*
 152                  * Check remaining flags.
 153                  */
 154                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
 155                         if (*cmd == '=')
 156                                 git_set_exec_path(cmd + 1);
 157                         else {
 158                                 puts(git_exec_path());
 159                                 trace2_cmd_name("_query_");
 160                                 exit(0);
 161                         }
 162                 } else if (!strcmp(cmd, "--html-path")) {
 163                         puts(system_path(GIT_HTML_PATH));
 164                         trace2_cmd_name("_query_");
 165                         exit(0);
 166                 } else if (!strcmp(cmd, "--man-path")) {
 167                         puts(system_path(GIT_MAN_PATH));
 168                         trace2_cmd_name("_query_");
 169                         exit(0);
 170                 } else if (!strcmp(cmd, "--info-path")) {
 171                         puts(system_path(GIT_INFO_PATH));
 172                         trace2_cmd_name("_query_");
 173                         exit(0);
 174                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 175                         use_pager = 1;
 176                 } else if (!strcmp(cmd, "-P") || !strcmp(cmd, "--no-pager")) {
 177                         use_pager = 0;
 178                         if (envchanged)
 179                                 *envchanged = 1;
 180                 } else if (!strcmp(cmd, "--no-replace-objects")) {
 181                         read_replace_refs = 0;
 182                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 183                         if (envchanged)
 184                                 *envchanged = 1;
 185                 } else if (!strcmp(cmd, "--git-dir")) {
 186                         if (*argc < 2) {
 187                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "--git-dir");
 188                                 usage(git_usage_string);
 189                         }
 190                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 191                         if (envchanged)
 192                                 *envchanged = 1;
 193                         (*argv)++;
 194                         (*argc)--;
 195                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 196                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 197                         if (envchanged)
 198                                 *envchanged = 1;
 199                 } else if (!strcmp(cmd, "--namespace")) {
 200                         if (*argc < 2) {
 201                                 fprintf(stderr, _("no namespace given for --namespace\n" ));
 202                                 usage(git_usage_string);
 203                         }
 204                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 205                         if (envchanged)
 206                                 *envchanged = 1;
 207                         (*argv)++;
 208                         (*argc)--;
 209                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 210                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 211                         if (envchanged)
 212                                 *envchanged = 1;
 213                 } else if (!strcmp(cmd, "--work-tree")) {
 214                         if (*argc < 2) {
 215                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "--work-tree");
 216                                 usage(git_usage_string);
 217                         }
 218                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 219                         if (envchanged)
 220                                 *envchanged = 1;
 221                         (*argv)++;
 222                         (*argc)--;
 223                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 224                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 225                         if (envchanged)
 226                                 *envchanged = 1;
 227                 } else if (!strcmp(cmd, "--bare")) {
 228                         char *cwd = xgetcwd();
 229                         is_bare_repository_cfg = 1;
 230                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 231                         free(cwd);
 232                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 233                         if (envchanged)
 234                                 *envchanged = 1;
 235                 } else if (!strcmp(cmd, "-c")) {
 236                         if (*argc < 2) {
 237                                 fprintf(stderr, _("-c expects a configuration string\n" ));
 238                                 usage(git_usage_string);
 239                         }
 240                         git_config_push_parameter((*argv)[1]);
 241                         (*argv)++;
 242                         (*argc)--;
 243                 } else if (!strcmp(cmd, "--config-env")) {
 244                         if (*argc < 2) {
 245                                 fprintf(stderr, _("no config key given for --config-env\n" ));
 246                                 usage(git_usage_string);
 247                         }
 248                         git_config_push_env((*argv)[1]);
 249                         (*argv)++;
 250                         (*argc)--;
 251                 } else if (skip_prefix(cmd, "--config-env=", &cmd)) {
 252                         git_config_push_env(cmd);
 253                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
 254                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 255                         if (envchanged)
 256                                 *envchanged = 1;
 257                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 258                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 259                         if (envchanged)
 260                                 *envchanged = 1;
 261                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
 262                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 263                         if (envchanged)
 264                                 *envchanged = 1;
 265                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 266                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 267                         if (envchanged)
 268                                 *envchanged = 1;
 269                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
 270                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 271                         if (envchanged)
 272                                 *envchanged = 1;
 273                 } else if (!strcmp(cmd, "--no-optional-locks")) {
 274                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 275                         if (envchanged)
 276                                 *envchanged = 1;
 277                 } else if (!strcmp(cmd, "--shallow-file")) {
 278                         (*argv)++;
 279                         (*argc)--;
 280                         set_alternate_shallow_file(the_repository, (*argv)[0], 1);
 281                         if (envchanged)
 282                                 *envchanged = 1;
 283                 } else if (!strcmp(cmd, "-C")) {
 284                         if (*argc < 2) {
 285                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "-C");
 286                                 usage(git_usage_string);
 287                         }
 288                         if ((*argv)[1][0]) {
 289                                 if (chdir((*argv)[1]))
 290                                         die_errno("cannot change to '%s'", (*argv)[1]);
 291                                 if (envchanged)
 292                                         *envchanged = 1;
 293                         }
 294                         (*argv)++;
 295                         (*argc)--;
 296                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 297                         trace2_cmd_name("_query_");
 298                         if (!strcmp(cmd, "parseopt")) {
 299                                 struct string_list list = STRING_LIST_INIT_DUP;
 300                                 int i;
 301
 302                                 list_builtins(&list, NO_PARSEOPT);
 303                                 for (i = 0; i < list.nr; i++)
 304                                         printf("%s ", list.items[i].string);
 305                                 string_list_clear(&list, 0);
 306                                 exit(0);
 307                         } else {
 308                                 exit(list_cmds(cmd));
 309                         }
 310                 } else {
 311                         fprintf(stderr, _("unknown option: %s\n"), cmd);
 312                         usage(git_usage_string);
 313                 }
 314
 315                 (*argv)++;
 316                 (*argc)--;
 317         }
 318         return (*argv) - orig_argv;
 319 }
 320
 321 static int handle_alias(int *argcp, const char ***argv)
 322 {
 323         int envchanged = 0, ret = 0, saved_errno = errno;
 324         int count, option_count;
 325         const char **new_argv;
 326         const char *alias_command;
 327         char *alias_string;
 328
 329         alias_command = (*argv)[0];
 330         alias_string = alias_lookup(alias_command);
 331         if (alias_string) {
 332                 if (*argcp > 1 && !strcmp((*argv)[1], "-h"))
 333                         fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
 334                                    alias_command, alias_string);
 335                 if (alias_string[0] == '!') {
 336                         struct child_process child = CHILD_PROCESS_INIT;
 337                         int nongit_ok;
 338
 339                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 340                         setup_git_directory_gently(&nongit_ok);
 341
 342                         commit_pager_choice();
 343
 344                         child.use_shell = 1;
 345                         child.clean_on_exit = 1;
 346                         child.wait_after_clean = 1;
 347                         child.trace2_child_class = "shell_alias";
 348                         strvec_push(&child.args, alias_string + 1);
 349                         strvec_pushv(&child.args, (*argv) + 1);
 350
 351                         trace2_cmd_alias(alias_command, child.args.v);
 352                         trace2_cmd_list_config();
 353                         trace2_cmd_list_env_vars();
 354                         trace2_cmd_name("_run_shell_alias_");
 355
 356                         ret = run_command(&child);
 357                         if (ret >= 0)   /* normal exit */
 358                                 exit(ret);
 359
 360                         die_errno(_("while expanding alias '%s': '%s'"),
 361                                   alias_command, alias_string + 1);
 362                 }
 363                 count = split_cmdline(alias_string, &new_argv);
 364                 if (count < 0)
 365                         die(_("bad alias.%s string: %s"), alias_command,
 366                             _(split_cmdline_strerror(count)));
 367                 option_count = handle_options(&new_argv, &count, &envchanged);
 368                 if (envchanged)
 369                         die(_("alias '%s' changes environment variables.\n"
 370                               "You can use '!git' in the alias to do this"),
 371                             alias_command);
 372                 MOVE_ARRAY(new_argv - option_count, new_argv, count);
 373                 new_argv -= option_count;
 374
 375                 if (count < 1)
 376                         die(_("empty alias for %s"), alias_command);
 377
 378                 if (!strcmp(alias_command, new_argv[0]))
 379                         die(_("recursive alias: %s"), alias_command);
 380
 381                 trace_argv_printf(new_argv,
 382                                   "trace: alias expansion: %s =>",
 383                                   alias_command);
 384
 385                 REALLOC_ARRAY(new_argv, count + *argcp);
 386                 /* insert after command name */
 387                 COPY_ARRAY(new_argv + count, *argv + 1, *argcp);
 388
 389                 trace2_cmd_alias(alias_command, new_argv);
 390                 trace2_cmd_list_config();
 391                 trace2_cmd_list_env_vars();
 392
 393                 *argv = new_argv;
 394                 *argcp += count - 1;
 395
 396                 ret = 1;
 397         }
 398
 399         errno = saved_errno;
 400
 401         return ret;
 402 }
 403
 404 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 405 {
 406         int status, help;
 407         struct stat st;
 408         const char *prefix;
 409         int run_setup = (p->option & (RUN_SETUP | RUN_SETUP_GENTLY));
 410
 411         help = argc == 2 && !strcmp(argv[1], "-h");
 412         if (help && (run_setup & RUN_SETUP))
 413                 /* demote to GENTLY to allow 'git cmd -h' outside repo */
 414                 run_setup = RUN_SETUP_GENTLY;
 415
 416         if (run_setup & RUN_SETUP) {
 417                 prefix = setup_git_directory();
 418         } else if (run_setup & RUN_SETUP_GENTLY) {
 419                 int nongit_ok;
 420                 prefix = setup_git_directory_gently(&nongit_ok);
 421         } else {
 422                 prefix = NULL;
 423         }
 424         assert(!prefix || *prefix);
 425         precompose_argv_prefix(argc, argv, NULL);
 426         if (use_pager == -1 && run_setup &&
 427                 !(p->option & DELAY_PAGER_CONFIG))
 428                 use_pager = check_pager_config(p->cmd);
 429         if (use_pager == -1 && p->option & USE_PAGER)
 430                 use_pager = 1;
 431         if (run_setup && startup_info->have_repository)
 432                 /* get_git_dir() may set up repo, avoid that */
 433                 trace_repo_setup();
 434         commit_pager_choice();
 435
 436         if (!help && p->option & NEED_WORK_TREE)
 437                 setup_work_tree();
 438
 439         trace_argv_printf(argv, "trace: built-in: git");
 440         trace2_cmd_name(p->cmd);
 441         trace2_cmd_list_config();
 442         trace2_cmd_list_env_vars();
 443
 444         validate_cache_entries(the_repository->index);
 445         status = p->fn(argc, argv, prefix);
 446         validate_cache_entries(the_repository->index);
 447
 448         if (status)
 449                 return status;
 450
 451         /* Somebody closed stdout? */
 452         if (fstat(fileno(stdout), &st))
 453                 return 0;
 454         /* Ignore write errors for pipes and sockets.. */
 455         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 456                 return 0;
 457
 458         /* Check for ENOSPC and EIO errors.. */
 459         if (fflush(stdout))
 460                 die_errno(_("write failure on standard output"));
 461         if (ferror(stdout))
 462                 die(_("unknown write failure on standard output"));
 463         if (fclose(stdout))
 464                 die_errno(_("close failed on standard output"));
 465         return 0;
 466 }
 467
 468 static struct cmd_struct commands[] = {
 469         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 470         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 471         { "annotate", cmd_annotate, RUN_SETUP },
 472         { "apply", cmd_apply, RUN_SETUP_GENTLY },
 473         { "archive", cmd_archive, RUN_SETUP_GENTLY },
 474         { "bisect", cmd_bisect, RUN_SETUP },
 475         { "blame", cmd_blame, RUN_SETUP },
 476         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 477         { "bugreport", cmd_bugreport, RUN_SETUP_GENTLY },
 478         { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 479         { "cat-file", cmd_cat_file, RUN_SETUP },
 480         { "check-attr", cmd_check_attr, RUN_SETUP },
 481         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 482         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 483         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 484         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 485         { "checkout--worker", cmd_checkout__worker,
 486                 RUN_SETUP | NEED_WORK_TREE },
 487         { "checkout-index", cmd_checkout_index,
 488                 RUN_SETUP | NEED_WORK_TREE},
 489         { "cherry", cmd_cherry, RUN_SETUP },
 490         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 491         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 492         { "clone", cmd_clone },
 493         { "column", cmd_column, RUN_SETUP_GENTLY },
 494         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 495         { "commit-graph", cmd_commit_graph, RUN_SETUP },
 496         { "commit-tree", cmd_commit_tree, RUN_SETUP },
 497         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 498         { "count-objects", cmd_count_objects, RUN_SETUP },
 499         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 500         { "credential-cache", cmd_credential_cache },
 501         { "credential-cache--daemon", cmd_credential_cache_daemon },
 502         { "credential-store", cmd_credential_store },
 503         { "describe", cmd_describe, RUN_SETUP },
 504         { "diagnose", cmd_diagnose, RUN_SETUP_GENTLY },
 505         { "diff", cmd_diff, NO_PARSEOPT },
 506         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 507         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 508         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 509         { "difftool", cmd_difftool, RUN_SETUP_GENTLY },
 510         { "fast-export", cmd_fast_export, RUN_SETUP },
 511         { "fast-import", cmd_fast_import, RUN_SETUP | NO_PARSEOPT },
 512         { "fetch", cmd_fetch, RUN_SETUP },
 513         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 514         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 515         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 516         { "for-each-repo", cmd_for_each_repo, RUN_SETUP_GENTLY },
 517         { "format-patch", cmd_format_patch, RUN_SETUP },
 518         { "fsck", cmd_fsck, RUN_SETUP },
 519         { "fsck-objects", cmd_fsck, RUN_SETUP },
 520         { "fsmonitor--daemon", cmd_fsmonitor__daemon, RUN_SETUP },
 521         { "gc", cmd_gc, RUN_SETUP },
 522         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 523         { "grep", cmd_grep, RUN_SETUP_GENTLY },
 524         { "hash-object", cmd_hash_object },
 525         { "help", cmd_help },
 526         { "hook", cmd_hook, RUN_SETUP },
 527         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 528         { "init", cmd_init_db },
 529         { "init-db", cmd_init_db },
 530         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 531         { "log", cmd_log, RUN_SETUP },
 532         { "ls-files", cmd_ls_files, RUN_SETUP },
 533         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 534         { "ls-tree", cmd_ls_tree, RUN_SETUP },
 535         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },
 536         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 537         { "maintenance", cmd_maintenance, RUN_SETUP },
 538         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 539         { "merge-base", cmd_merge_base, RUN_SETUP },
 540         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 541         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 542         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 543         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 544         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 545         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 546         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 547         { "merge-tree", cmd_merge_tree, RUN_SETUP },
 548         { "mktag", cmd_mktag, RUN_SETUP },
 549         { "mktree", cmd_mktree, RUN_SETUP },
 550         { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP },
 551         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 552         { "name-rev", cmd_name_rev, RUN_SETUP },
 553         { "notes", cmd_notes, RUN_SETUP },
 554         { "pack-objects", cmd_pack_objects, RUN_SETUP },
 555         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 556         { "pack-refs", cmd_pack_refs, RUN_SETUP },
 557         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 558         { "pickaxe", cmd_blame, RUN_SETUP },
 559         { "prune", cmd_prune, RUN_SETUP },
 560         { "prune-packed", cmd_prune_packed, RUN_SETUP },
 561         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 562         { "push", cmd_push, RUN_SETUP },
 563         { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },
 564         { "read-tree", cmd_read_tree, RUN_SETUP },
 565         { "rebase", cmd_rebase, RUN_SETUP | NEED_WORK_TREE },
 566         { "receive-pack", cmd_receive_pack },
 567         { "reflog", cmd_reflog, RUN_SETUP },
 568         { "remote", cmd_remote, RUN_SETUP },
 569         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 570         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 571         { "repack", cmd_repack, RUN_SETUP },
 572         { "replace", cmd_replace, RUN_SETUP },
 573         { "rerere", cmd_rerere, RUN_SETUP },
 574         { "reset", cmd_reset, RUN_SETUP },
 575         { "restore", cmd_restore, RUN_SETUP | NEED_WORK_TREE },
 576         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 577         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 578         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 579         { "rm", cmd_rm, RUN_SETUP },
 580         { "send-pack", cmd_send_pack, RUN_SETUP },
 581         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 582         { "show", cmd_show, RUN_SETUP },
 583         { "show-branch", cmd_show_branch, RUN_SETUP },
 584         { "show-index", cmd_show_index, RUN_SETUP_GENTLY },
 585         { "show-ref", cmd_show_ref, RUN_SETUP },
 586         { "sparse-checkout", cmd_sparse_checkout, RUN_SETUP | NEED_WORK_TREE },
 587         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 588         { "stash", cmd_stash, RUN_SETUP | NEED_WORK_TREE },
 589         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 590         { "stripspace", cmd_stripspace },
 591         { "submodule--helper", cmd_submodule__helper, RUN_SETUP },
 592         { "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },
 593         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 594         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 595         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 596         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 597         { "update-index", cmd_update_index, RUN_SETUP },
 598         { "update-ref", cmd_update_ref, RUN_SETUP },
 599         { "update-server-info", cmd_update_server_info, RUN_SETUP },
 600         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 601         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 602         { "upload-pack", cmd_upload_pack },
 603         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 604         { "verify-commit", cmd_verify_commit, RUN_SETUP },
 605         { "verify-pack", cmd_verify_pack },
 606         { "verify-tag", cmd_verify_tag, RUN_SETUP },
 607         { "version", cmd_version },
 608         { "whatchanged", cmd_whatchanged, RUN_SETUP },
 609         { "worktree", cmd_worktree, RUN_SETUP },
 610         { "write-tree", cmd_write_tree, RUN_SETUP },
 611 };
 612
 613 static struct cmd_struct *get_builtin(const char *s)
 614 {
 615         int i;
 616         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 617                 struct cmd_struct *p = commands + i;
 618                 if (!strcmp(s, p->cmd))
 619                         return p;
 620         }
 621         return NULL;
 622 }
 623
 624 int is_builtin(const char *s)
 625 {
 626         return !!get_builtin(s);
 627 }
 628
 629 static void list_builtins(struct string_list *out, unsigned int exclude_option)
 630 {
 631         int i;
 632         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 633                 if (exclude_option &&
 634                     (commands[i].option & exclude_option))
 635                         continue;
 636                 string_list_append(out, commands[i].cmd);
 637         }
 638 }
 639
 640 void load_builtin_commands(const char *prefix, struct cmdnames *cmds)
 641 {
 642         const char *name;
 643         int i;
 644
 645         /*
 646          * Callers can ask for a subset of the commands based on a certain
 647          * prefix, which is then dropped from the added names. The names in
 648          * the `commands[]` array do not have the `git-` prefix, though,
 649          * therefore we must expect the `prefix` to at least start with `git-`.
 650          */
 651         if (!skip_prefix(prefix, "git-", &prefix))
 652                 BUG("prefix '%s' must start with 'git-'", prefix);
 653
 654         for (i = 0; i < ARRAY_SIZE(commands); i++)
 655                 if (skip_prefix(commands[i].cmd, prefix, &name))
 656                         add_cmdname(cmds, name, strlen(name));
 657 }
 658
 659 #ifdef STRIP_EXTENSION
 660 static void strip_extension(const char **argv)
 661 {
 662         size_t len;
 663
 664         if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 665                 argv[0] = xmemdupz(argv[0], len);
 666 }
 667 #else
 668 #define strip_extension(cmd)
 669 #endif
 670
 671 static void handle_builtin(int argc, const char **argv)
 672 {
 673         struct strvec args = STRVEC_INIT;
 674         const char *cmd;
 675         struct cmd_struct *builtin;
 676
 677         strip_extension(argv);
 678         cmd = argv[0];
 679
 680         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 681         if (argc > 1 && !strcmp(argv[1], "--help")) {
 682                 int i;
 683
 684                 argv[1] = argv[0];
 685                 argv[0] = cmd = "help";
 686
 687                 for (i = 0; i < argc; i++) {
 688                         strvec_push(&args, argv[i]);
 689                         if (!i)
 690                                 strvec_push(&args, "--exclude-guides");
 691                 }
 692
 693                 argc++;
 694                 argv = args.v;
 695         }
 696
 697         builtin = get_builtin(cmd);
 698         if (builtin)
 699                 exit(run_builtin(builtin, argc, argv));
 700         strvec_clear(&args);
 701 }
 702
 703 static void execv_dashed_external(const char **argv)
 704 {
 705         struct child_process cmd = CHILD_PROCESS_INIT;
 706         int status;
 707
 708         if (use_pager == -1 && !is_builtin(argv[0]))
 709                 use_pager = check_pager_config(argv[0]);
 710         commit_pager_choice();
 711
 712         strvec_pushf(&cmd.args, "git-%s", argv[0]);
 713         strvec_pushv(&cmd.args, argv + 1);
 714         cmd.clean_on_exit = 1;
 715         cmd.wait_after_clean = 1;
 716         cmd.silent_exec_failure = 1;
 717         cmd.trace2_child_class = "dashed";
 718
 719         trace2_cmd_name("_run_dashed_");
 720
 721         /*
 722          * The code in run_command() logs trace2 child_start/child_exit
 723          * events, so we do not need to report exec/exec_result events here.
 724          */
 725         trace_argv_printf(cmd.args.v, "trace: exec:");
 726
 727         /*
 728          * If we fail because the command is not found, it is
 729          * OK to return. Otherwise, we just pass along the status code,
 730          * or our usual generic code if we were not even able to exec
 731          * the program.
 732          */
 733         status = run_command(&cmd);
 734
 735         /*
 736          * If the child process ran and we are now going to exit, emit a
 737          * generic string as our trace2 command verb to indicate that we
 738          * launched a dashed command.
 739          */
 740         if (status >= 0)
 741                 exit(status);
 742         else if (errno != ENOENT)
 743                 exit(128);
 744 }
 745
 746 static int run_argv(int *argcp, const char ***argv)
 747 {
 748         int done_alias = 0;
 749         struct string_list cmd_list = STRING_LIST_INIT_NODUP;
 750         struct string_list_item *seen;
 751
 752         while (1) {
 753                 /*
 754                  * If we tried alias and futzed with our environment,
 755                  * it no longer is safe to invoke builtins directly in
 756                  * general.  We have to spawn them as dashed externals.
 757                  *
 758                  * NEEDSWORK: if we can figure out cases
 759                  * where it is safe to do, we can avoid spawning a new
 760                  * process.
 761                  */
 762                 if (!done_alias)
 763                         handle_builtin(*argcp, *argv);
 764                 else if (get_builtin(**argv)) {
 765                         struct child_process cmd = CHILD_PROCESS_INIT;
 766                         int i;
 767
 768                         /*
 769                          * The current process is committed to launching a
 770                          * child process to run the command named in (**argv)
 771                          * and exiting.  Log a generic string as the trace2
 772                          * command verb to indicate this.  Note that the child
 773                          * process will log the actual verb when it runs.
 774                          */
 775                         trace2_cmd_name("_run_git_alias_");
 776
 777                         commit_pager_choice();
 778
 779                         strvec_push(&cmd.args, "git");
 780                         for (i = 0; i < *argcp; i++)
 781                                 strvec_push(&cmd.args, (*argv)[i]);
 782
 783                         trace_argv_printf(cmd.args.v, "trace: exec:");
 784
 785                         /*
 786                          * if we fail because the command is not found, it is
 787                          * OK to return. Otherwise, we just pass along the status code.
 788                          */
 789                         cmd.silent_exec_failure = 1;
 790                         cmd.clean_on_exit = 1;
 791                         cmd.wait_after_clean = 1;
 792                         cmd.trace2_child_class = "git_alias";
 793                         i = run_command(&cmd);
 794                         if (i >= 0 || errno != ENOENT)
 795                                 exit(i);
 796                         die("could not execute builtin %s", **argv);
 797                 }
 798
 799                 /* .. then try the external ones */
 800                 execv_dashed_external(*argv);
 801
 802                 seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);
 803                 if (seen) {
 804                         int i;
 805                         struct strbuf sb = STRBUF_INIT;
 806                         for (i = 0; i < cmd_list.nr; i++) {
 807                                 struct string_list_item *item = &cmd_list.items[i];
 808
 809                                 strbuf_addf(&sb, "\n  %s", item->string);
 810                                 if (item == seen)
 811                                         strbuf_addstr(&sb, " <==");
 812                                 else if (i == cmd_list.nr - 1)
 813                                         strbuf_addstr(&sb, " ==>");
 814                         }
 815                         die(_("alias loop detected: expansion of '%s' does"
 816                               " not terminate:%s"), cmd_list.items[0].string, sb.buf);
 817                 }
 818
 819                 string_list_append(&cmd_list, *argv[0]);
 820
 821                 /*
 822                  * It could be an alias -- this works around the insanity
 823                  * of overriding "git log" with "git show" by having
 824                  * alias.log = show
 825                  */
 826                 if (!handle_alias(argcp, argv))
 827                         break;
 828                 done_alias = 1;
 829         }
 830
 831         string_list_clear(&cmd_list, 0);
 832
 833         return done_alias;
 834 }
 835
 836 int cmd_main(int argc, const char **argv)
 837 {
 838         const char *cmd;
 839         int done_help = 0;
 840
 841         cmd = argv[0];
 842         if (!cmd)
 843                 cmd = "git-help";
 844         else {
 845                 const char *slash = find_last_dir_sep(cmd);
 846                 if (slash)
 847                         cmd = slash + 1;
 848         }
 849
 850         trace_command_performance(argv);
 851
 852         /*
 853          * "git-xxxx" is the same as "git xxxx", but we obviously:
 854          *
 855          *  - cannot take flags in between the "git" and the "xxxx".
 856          *  - cannot execute it externally (since it would just do
 857          *    the same thing over again)
 858          *
 859          * So we just directly call the builtin handler, and die if
 860          * that one cannot handle it.
 861          */
 862         if (skip_prefix(cmd, "git-", &cmd)) {
 863                 argv[0] = cmd;
 864                 handle_builtin(argc, argv);
 865                 die(_("cannot handle %s as a builtin"), cmd);
 866         }
 867
 868         /* Look for flags.. */
 869         argv++;
 870         argc--;
 871         handle_options(&argv, &argc, NULL);
 872
 873         if (!argc) {
 874                 /* The user didn't specify a command; give them help */
 875                 commit_pager_choice();
 876                 printf(_("usage: %s\n\n"), git_usage_string);
 877                 list_common_cmds_help();
 878                 printf("\n%s\n", _(git_more_info_string));
 879                 exit(1);
 880         }
 881
 882         if (!strcmp("--version", argv[0]) || !strcmp("-v", argv[0]))
 883                 argv[0] = "version";
 884         else if (!strcmp("--help", argv[0]) || !strcmp("-h", argv[0]))
 885                 argv[0] = "help";
 886
 887         cmd = argv[0];
 888
 889         /*
 890          * We use PATH to find git commands, but we prepend some higher
 891          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 892          * environment, and the $(gitexecdir) from the Makefile at build
 893          * time.
 894          */
 895         setup_path();
 896
 897         while (1) {
 898                 int was_alias = run_argv(&argc, &argv);
 899                 if (errno != ENOENT)
 900                         break;
 901                 if (was_alias) {
 902                         fprintf(stderr, _("expansion of alias '%s' failed; "
 903                                           "'%s' is not a git command\n"),
 904                                 cmd, argv[0]);
 905                         exit(1);
 906                 }
 907                 if (!done_help) {
 908                         cmd = argv[0] = help_unknown_cmd(cmd);
 909                         done_help = 1;
 910                 } else
 911                         break;
 912         }
 913
 914         fprintf(stderr, _("failed to run command '%s': %s\n"),
 915                 cmd, strerror(errno));
 916
 917         return 1;
 918 }