Andrew's git / gitweb.git / git.c
?
git.con commit git.c: convert --list-* to --list-cmds=* (0089521)
   1#include "builtin.h"
   2#include "config.h"
   3#include "exec_cmd.h"
   4#include "help.h"
   5#include "run-command.h"
   6
   7#define RUN_SETUP               (1<<0)
   8#define RUN_SETUP_GENTLY        (1<<1)
   9#define USE_PAGER               (1<<2)
  10/*
  11 * require working tree to be present -- anything uses this needs
  12 * RUN_SETUP for reading from the configuration file.
  13 */
  14#define NEED_WORK_TREE          (1<<3)
  15#define SUPPORT_SUPER_PREFIX    (1<<4)
  16#define DELAY_PAGER_CONFIG      (1<<5)
  17#define NO_PARSEOPT             (1<<6) /* parse-options is not used */
  18
  19struct cmd_struct {
  20        const char *cmd;
  21        int (*fn)(int, const char **, const char *);
  22        unsigned int option;
  23};
  24
  25const char git_usage_string[] =
  26        N_("git [--version] [--help] [-C <path>] [-c <name>=<value>]\n"
  27           "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  28           "           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
  29           "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  30           "           <command> [<args>]");
  31
  32const char git_more_info_string[] =
  33        N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  34           "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  35           "to read about a specific subcommand or concept.");
  36
  37static int use_pager = -1;
  38
  39static void list_builtins(unsigned int exclude_option, char sep);
  40
  41static int match_token(const char *spec, int len, const char *token)
  42{
  43        int token_len = strlen(token);
  44
  45        return len == token_len && !strncmp(spec, token, token_len);
  46}
  47
  48static int list_cmds(const char *spec)
  49{
  50        while (*spec) {
  51                const char *sep = strchrnul(spec, ',');
  52                int len = sep - spec;
  53
  54                if (match_token(spec, len, "builtins"))
  55                        list_builtins(0, '\n');
  56                else
  57                        die(_("unsupported command listing type '%s'"), spec);
  58                spec += len;
  59                if (*spec == ',')
  60                        spec++;
  61        }
  62        return 0;
  63}
  64
  65static void commit_pager_choice(void) {
  66        switch (use_pager) {
  67        case 0:
  68                setenv("GIT_PAGER", "cat", 1);
  69                break;
  70        case 1:
  71                setup_pager();
  72                break;
  73        default:
  74                break;
  75        }
  76}
  77
  78void setup_auto_pager(const char *cmd, int def)
  79{
  80        if (use_pager != -1 || pager_in_use())
  81                return;
  82        use_pager = check_pager_config(cmd);
  83        if (use_pager == -1)
  84                use_pager = def;
  85        commit_pager_choice();
  86}
  87
  88static int handle_options(const char ***argv, int *argc, int *envchanged)
  89{
  90        const char **orig_argv = *argv;
  91
  92        while (*argc > 0) {
  93                const char *cmd = (*argv)[0];
  94                if (cmd[0] != '-')
  95                        break;
  96
  97                /*
  98                 * For legacy reasons, the "version" and "help"
  99                 * commands can be written with "--" prepended
 100                 * to make them look like flags.
 101                 */
 102                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 103                        break;
 104
 105                /*
 106                 * Check remaining flags.
 107                 */
 108                if (skip_prefix(cmd, "--exec-path", &cmd)) {
 109                        if (*cmd == '=')
 110                                git_set_argv_exec_path(cmd + 1);
 111                        else {
 112                                puts(git_exec_path());
 113                                exit(0);
 114                        }
 115                } else if (!strcmp(cmd, "--html-path")) {
 116                        puts(system_path(GIT_HTML_PATH));
 117                        exit(0);
 118                } else if (!strcmp(cmd, "--man-path")) {
 119                        puts(system_path(GIT_MAN_PATH));
 120                        exit(0);
 121                } else if (!strcmp(cmd, "--info-path")) {
 122                        puts(system_path(GIT_INFO_PATH));
 123                        exit(0);
 124                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 125                        use_pager = 1;
 126                } else if (!strcmp(cmd, "--no-pager")) {
 127                        use_pager = 0;
 128                        if (envchanged)
 129                                *envchanged = 1;
 130                } else if (!strcmp(cmd, "--no-replace-objects")) {
 131                        check_replace_refs = 0;
 132                        setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 133                        if (envchanged)
 134                                *envchanged = 1;
 135                } else if (!strcmp(cmd, "--git-dir")) {
 136                        if (*argc < 2) {
 137                                fprintf(stderr, _("no directory given for --git-dir\n" ));
 138                                usage(git_usage_string);
 139                        }
 140                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 141                        if (envchanged)
 142                                *envchanged = 1;
 143                        (*argv)++;
 144                        (*argc)--;
 145                } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 146                        setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 147                        if (envchanged)
 148                                *envchanged = 1;
 149                } else if (!strcmp(cmd, "--namespace")) {
 150                        if (*argc < 2) {
 151                                fprintf(stderr, _("no namespace given for --namespace\n" ));
 152                                usage(git_usage_string);
 153                        }
 154                        setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 155                        if (envchanged)
 156                                *envchanged = 1;
 157                        (*argv)++;
 158                        (*argc)--;
 159                } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 160                        setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 161                        if (envchanged)
 162                                *envchanged = 1;
 163                } else if (!strcmp(cmd, "--work-tree")) {
 164                        if (*argc < 2) {
 165                                fprintf(stderr, _("no directory given for --work-tree\n" ));
 166                                usage(git_usage_string);
 167                        }
 168                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 169                        if (envchanged)
 170                                *envchanged = 1;
 171                        (*argv)++;
 172                        (*argc)--;
 173                } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 174                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 175                        if (envchanged)
 176                                *envchanged = 1;
 177                } else if (!strcmp(cmd, "--super-prefix")) {
 178                        if (*argc < 2) {
 179                                fprintf(stderr, _("no prefix given for --super-prefix\n" ));
 180                                usage(git_usage_string);
 181                        }
 182                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 183                        if (envchanged)
 184                                *envchanged = 1;
 185                        (*argv)++;
 186                        (*argc)--;
 187                } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 188                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 189                        if (envchanged)
 190                                *envchanged = 1;
 191                } else if (!strcmp(cmd, "--bare")) {
 192                        char *cwd = xgetcwd();
 193                        is_bare_repository_cfg = 1;
 194                        setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 195                        free(cwd);
 196                        setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 197                        if (envchanged)
 198                                *envchanged = 1;
 199                } else if (!strcmp(cmd, "-c")) {
 200                        if (*argc < 2) {
 201                                fprintf(stderr, _("-c expects a configuration string\n" ));
 202                                usage(git_usage_string);
 203                        }
 204                        git_config_push_parameter((*argv)[1]);
 205                        (*argv)++;
 206                        (*argc)--;
 207                } else if (!strcmp(cmd, "--literal-pathspecs")) {
 208                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 209                        if (envchanged)
 210                                *envchanged = 1;
 211                } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 212                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 213                        if (envchanged)
 214                                *envchanged = 1;
 215                } else if (!strcmp(cmd, "--glob-pathspecs")) {
 216                        setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 217                        if (envchanged)
 218                                *envchanged = 1;
 219                } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 220                        setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 221                        if (envchanged)
 222                                *envchanged = 1;
 223                } else if (!strcmp(cmd, "--icase-pathspecs")) {
 224                        setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 225                        if (envchanged)
 226                                *envchanged = 1;
 227                } else if (!strcmp(cmd, "--no-optional-locks")) {
 228                        setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 229                        if (envchanged)
 230                                *envchanged = 1;
 231                } else if (!strcmp(cmd, "--shallow-file")) {
 232                        (*argv)++;
 233                        (*argc)--;
 234                        set_alternate_shallow_file((*argv)[0], 1);
 235                        if (envchanged)
 236                                *envchanged = 1;
 237                } else if (!strcmp(cmd, "-C")) {
 238                        if (*argc < 2) {
 239                                fprintf(stderr, _("no directory given for -C\n" ));
 240                                usage(git_usage_string);
 241                        }
 242                        if ((*argv)[1][0]) {
 243                                if (chdir((*argv)[1]))
 244                                        die_errno("cannot change to '%s'", (*argv)[1]);
 245                                if (envchanged)
 246                                        *envchanged = 1;
 247                        }
 248                        (*argv)++;
 249                        (*argc)--;
 250                } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 251                        if (!strcmp(cmd, "parseopt")) {
 252                                list_builtins(NO_PARSEOPT, ' ');
 253                                exit(0);
 254                        } else {
 255                                exit(list_cmds(cmd));
 256                        }
 257                } else {
 258                        fprintf(stderr, _("unknown option: %s\n"), cmd);
 259                        usage(git_usage_string);
 260                }
 261
 262                (*argv)++;
 263                (*argc)--;
 264        }
 265        return (*argv) - orig_argv;
 266}
 267
 268static int handle_alias(int *argcp, const char ***argv)
 269{
 270        int envchanged = 0, ret = 0, saved_errno = errno;
 271        int count, option_count;
 272        const char **new_argv;
 273        const char *alias_command;
 274        char *alias_string;
 275
 276        alias_command = (*argv)[0];
 277        alias_string = alias_lookup(alias_command);
 278        if (alias_string) {
 279                if (alias_string[0] == '!') {
 280                        struct child_process child = CHILD_PROCESS_INIT;
 281                        int nongit_ok;
 282
 283                        /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 284                        setup_git_directory_gently(&nongit_ok);
 285
 286                        commit_pager_choice();
 287
 288                        child.use_shell = 1;
 289                        argv_array_push(&child.args, alias_string + 1);
 290                        argv_array_pushv(&child.args, (*argv) + 1);
 291
 292                        ret = run_command(&child);
 293                        if (ret >= 0)   /* normal exit */
 294                                exit(ret);
 295
 296                        die_errno("while expanding alias '%s': '%s'",
 297                            alias_command, alias_string + 1);
 298                }
 299                count = split_cmdline(alias_string, &new_argv);
 300                if (count < 0)
 301                        die("Bad alias.%s string: %s", alias_command,
 302                            split_cmdline_strerror(count));
 303                option_count = handle_options(&new_argv, &count, &envchanged);
 304                if (envchanged)
 305                        die("alias '%s' changes environment variables.\n"
 306                                 "You can use '!git' in the alias to do this",
 307                                 alias_command);
 308                memmove(new_argv - option_count, new_argv,
 309                                count * sizeof(char *));
 310                new_argv -= option_count;
 311
 312                if (count < 1)
 313                        die("empty alias for %s", alias_command);
 314
 315                if (!strcmp(alias_command, new_argv[0]))
 316                        die("recursive alias: %s", alias_command);
 317
 318                trace_argv_printf(new_argv,
 319                                  "trace: alias expansion: %s =>",
 320                                  alias_command);
 321
 322                REALLOC_ARRAY(new_argv, count + *argcp);
 323                /* insert after command name */
 324                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 325
 326                *argv = new_argv;
 327                *argcp += count - 1;
 328
 329                ret = 1;
 330        }
 331
 332        errno = saved_errno;
 333
 334        return ret;
 335}
 336
 337static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 338{
 339        int status, help;
 340        struct stat st;
 341        const char *prefix;
 342
 343        prefix = NULL;
 344        help = argc == 2 && !strcmp(argv[1], "-h");
 345        if (!help) {
 346                if (p->option & RUN_SETUP)
 347                        prefix = setup_git_directory();
 348                else if (p->option & RUN_SETUP_GENTLY) {
 349                        int nongit_ok;
 350                        prefix = setup_git_directory_gently(&nongit_ok);
 351                }
 352
 353                if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
 354                    !(p->option & DELAY_PAGER_CONFIG))
 355                        use_pager = check_pager_config(p->cmd);
 356                if (use_pager == -1 && p->option & USE_PAGER)
 357                        use_pager = 1;
 358
 359                if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 360                    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 361                        trace_repo_setup(prefix);
 362        }
 363        commit_pager_choice();
 364
 365        if (!help && get_super_prefix()) {
 366                if (!(p->option & SUPPORT_SUPER_PREFIX))
 367                        die("%s doesn't support --super-prefix", p->cmd);
 368        }
 369
 370        if (!help && p->option & NEED_WORK_TREE)
 371                setup_work_tree();
 372
 373        trace_argv_printf(argv, "trace: built-in: git");
 374
 375        status = p->fn(argc, argv, prefix);
 376        if (status)
 377                return status;
 378
 379        /* Somebody closed stdout? */
 380        if (fstat(fileno(stdout), &st))
 381                return 0;
 382        /* Ignore write errors for pipes and sockets.. */
 383        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 384                return 0;
 385
 386        /* Check for ENOSPC and EIO errors.. */
 387        if (fflush(stdout))
 388                die_errno("write failure on standard output");
 389        if (ferror(stdout))
 390                die("unknown write failure on standard output");
 391        if (fclose(stdout))
 392                die_errno("close failed on standard output");
 393        return 0;
 394}
 395
 396static struct cmd_struct commands[] = {
 397        { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 398        { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 399        { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
 400        { "apply", cmd_apply, RUN_SETUP_GENTLY },
 401        { "archive", cmd_archive, RUN_SETUP_GENTLY },
 402        { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 403        { "blame", cmd_blame, RUN_SETUP },
 404        { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 405        { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
 406        { "cat-file", cmd_cat_file, RUN_SETUP },
 407        { "check-attr", cmd_check_attr, RUN_SETUP },
 408        { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 409        { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 410        { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 411        { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 412        { "checkout-index", cmd_checkout_index,
 413                RUN_SETUP | NEED_WORK_TREE},
 414        { "cherry", cmd_cherry, RUN_SETUP },
 415        { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 416        { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 417        { "clone", cmd_clone },
 418        { "column", cmd_column, RUN_SETUP_GENTLY },
 419        { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 420        { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
 421        { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 422        { "count-objects", cmd_count_objects, RUN_SETUP },
 423        { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 424        { "describe", cmd_describe, RUN_SETUP },
 425        { "diff", cmd_diff, NO_PARSEOPT },
 426        { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 427        { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 428        { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 429        { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 430        { "fast-export", cmd_fast_export, RUN_SETUP },
 431        { "fetch", cmd_fetch, RUN_SETUP },
 432        { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 433        { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 434        { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 435        { "format-patch", cmd_format_patch, RUN_SETUP },
 436        { "fsck", cmd_fsck, RUN_SETUP },
 437        { "fsck-objects", cmd_fsck, RUN_SETUP },
 438        { "gc", cmd_gc, RUN_SETUP },
 439        { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 440        { "grep", cmd_grep, RUN_SETUP_GENTLY },
 441        { "hash-object", cmd_hash_object },
 442        { "help", cmd_help },
 443        { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 444        { "init", cmd_init_db },
 445        { "init-db", cmd_init_db },
 446        { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 447        { "log", cmd_log, RUN_SETUP },
 448        { "ls-files", cmd_ls_files, RUN_SETUP },
 449        { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 450        { "ls-tree", cmd_ls_tree, RUN_SETUP },
 451        { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
 452        { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 453        { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 454        { "merge-base", cmd_merge_base, RUN_SETUP },
 455        { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 456        { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 457        { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 458        { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 459        { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 460        { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 461        { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 462        { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
 463        { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
 464        { "mktree", cmd_mktree, RUN_SETUP },
 465        { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 466        { "name-rev", cmd_name_rev, RUN_SETUP },
 467        { "notes", cmd_notes, RUN_SETUP },
 468        { "pack-objects", cmd_pack_objects, RUN_SETUP },
 469        { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 470        { "pack-refs", cmd_pack_refs, RUN_SETUP },
 471        { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 472        { "pickaxe", cmd_blame, RUN_SETUP },
 473        { "prune", cmd_prune, RUN_SETUP },
 474        { "prune-packed", cmd_prune_packed, RUN_SETUP },
 475        { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 476        { "push", cmd_push, RUN_SETUP },
 477        { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 478        { "rebase--helper", cmd_rebase__helper, RUN_SETUP | NEED_WORK_TREE },
 479        { "receive-pack", cmd_receive_pack },
 480        { "reflog", cmd_reflog, RUN_SETUP },
 481        { "remote", cmd_remote, RUN_SETUP },
 482        { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 483        { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 484        { "repack", cmd_repack, RUN_SETUP },
 485        { "replace", cmd_replace, RUN_SETUP },
 486        { "rerere", cmd_rerere, RUN_SETUP },
 487        { "reset", cmd_reset, RUN_SETUP },
 488        { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 489        { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 490        { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 491        { "rm", cmd_rm, RUN_SETUP },
 492        { "send-pack", cmd_send_pack, RUN_SETUP },
 493        { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 494        { "show", cmd_show, RUN_SETUP },
 495        { "show-branch", cmd_show_branch, RUN_SETUP },
 496        { "show-ref", cmd_show_ref, RUN_SETUP },
 497        { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 498        { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 499        { "stripspace", cmd_stripspace },
 500        { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
 501        { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 502        { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 503        { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 504        { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 505        { "update-index", cmd_update_index, RUN_SETUP },
 506        { "update-ref", cmd_update_ref, RUN_SETUP },
 507        { "update-server-info", cmd_update_server_info, RUN_SETUP },
 508        { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 509        { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 510        { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 511        { "verify-commit", cmd_verify_commit, RUN_SETUP },
 512        { "verify-pack", cmd_verify_pack },
 513        { "verify-tag", cmd_verify_tag, RUN_SETUP },
 514        { "version", cmd_version },
 515        { "whatchanged", cmd_whatchanged, RUN_SETUP },
 516        { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
 517        { "write-tree", cmd_write_tree, RUN_SETUP },
 518};
 519
 520static struct cmd_struct *get_builtin(const char *s)
 521{
 522        int i;
 523        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 524                struct cmd_struct *p = commands + i;
 525                if (!strcmp(s, p->cmd))
 526                        return p;
 527        }
 528        return NULL;
 529}
 530
 531int is_builtin(const char *s)
 532{
 533        return !!get_builtin(s);
 534}
 535
 536static void list_builtins(unsigned int exclude_option, char sep)
 537{
 538        int i;
 539        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 540                if (exclude_option &&
 541                    (commands[i].option & exclude_option))
 542                        continue;
 543                printf("%s%c", commands[i].cmd, sep);
 544        }
 545}
 546
 547#ifdef STRIP_EXTENSION
 548static void strip_extension(const char **argv)
 549{
 550        size_t len;
 551
 552        if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 553                argv[0] = xmemdupz(argv[0], len);
 554}
 555#else
 556#define strip_extension(cmd)
 557#endif
 558
 559static void handle_builtin(int argc, const char **argv)
 560{
 561        struct argv_array args = ARGV_ARRAY_INIT;
 562        const char *cmd;
 563        struct cmd_struct *builtin;
 564
 565        strip_extension(argv);
 566        cmd = argv[0];
 567
 568        /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 569        if (argc > 1 && !strcmp(argv[1], "--help")) {
 570                int i;
 571
 572                argv[1] = argv[0];
 573                argv[0] = cmd = "help";
 574
 575                for (i = 0; i < argc; i++) {
 576                        argv_array_push(&args, argv[i]);
 577                        if (!i)
 578                                argv_array_push(&args, "--exclude-guides");
 579                }
 580
 581                argc++;
 582                argv = args.argv;
 583        }
 584
 585        builtin = get_builtin(cmd);
 586        if (builtin)
 587                exit(run_builtin(builtin, argc, argv));
 588        argv_array_clear(&args);
 589}
 590
 591static void execv_dashed_external(const char **argv)
 592{
 593        struct child_process cmd = CHILD_PROCESS_INIT;
 594        int status;
 595
 596        if (get_super_prefix())
 597                die("%s doesn't support --super-prefix", argv[0]);
 598
 599        if (use_pager == -1 && !is_builtin(argv[0]))
 600                use_pager = check_pager_config(argv[0]);
 601        commit_pager_choice();
 602
 603        argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 604        argv_array_pushv(&cmd.args, argv + 1);
 605        cmd.clean_on_exit = 1;
 606        cmd.wait_after_clean = 1;
 607        cmd.silent_exec_failure = 1;
 608
 609        trace_argv_printf(cmd.args.argv, "trace: exec:");
 610
 611        /*
 612         * If we fail because the command is not found, it is
 613         * OK to return. Otherwise, we just pass along the status code,
 614         * or our usual generic code if we were not even able to exec
 615         * the program.
 616         */
 617        status = run_command(&cmd);
 618        if (status >= 0)
 619                exit(status);
 620        else if (errno != ENOENT)
 621                exit(128);
 622}
 623
 624static int run_argv(int *argcp, const char ***argv)
 625{
 626        int done_alias = 0;
 627
 628        while (1) {
 629                /*
 630                 * If we tried alias and futzed with our environment,
 631                 * it no longer is safe to invoke builtins directly in
 632                 * general.  We have to spawn them as dashed externals.
 633                 *
 634                 * NEEDSWORK: if we can figure out cases
 635                 * where it is safe to do, we can avoid spawning a new
 636                 * process.
 637                 */
 638                if (!done_alias)
 639                        handle_builtin(*argcp, *argv);
 640
 641                /* .. then try the external ones */
 642                execv_dashed_external(*argv);
 643
 644                /* It could be an alias -- this works around the insanity
 645                 * of overriding "git log" with "git show" by having
 646                 * alias.log = show
 647                 */
 648                if (done_alias)
 649                        break;
 650                if (!handle_alias(argcp, argv))
 651                        break;
 652                done_alias = 1;
 653        }
 654
 655        return done_alias;
 656}
 657
 658int cmd_main(int argc, const char **argv)
 659{
 660        const char *cmd;
 661        int done_help = 0;
 662
 663        cmd = argv[0];
 664        if (!cmd)
 665                cmd = "git-help";
 666        else {
 667                const char *slash = find_last_dir_sep(cmd);
 668                if (slash)
 669                        cmd = slash + 1;
 670        }
 671
 672        trace_command_performance(argv);
 673
 674        /*
 675         * "git-xxxx" is the same as "git xxxx", but we obviously:
 676         *
 677         *  - cannot take flags in between the "git" and the "xxxx".
 678         *  - cannot execute it externally (since it would just do
 679         *    the same thing over again)
 680         *
 681         * So we just directly call the builtin handler, and die if
 682         * that one cannot handle it.
 683         */
 684        if (skip_prefix(cmd, "git-", &cmd)) {
 685                argv[0] = cmd;
 686                handle_builtin(argc, argv);
 687                die("cannot handle %s as a builtin", cmd);
 688        }
 689
 690        /* Look for flags.. */
 691        argv++;
 692        argc--;
 693        handle_options(&argv, &argc, NULL);
 694        if (argc > 0) {
 695                /* translate --help and --version into commands */
 696                skip_prefix(argv[0], "--", &argv[0]);
 697        } else {
 698                /* The user didn't specify a command; give them help */
 699                commit_pager_choice();
 700                printf("usage: %s\n\n", git_usage_string);
 701                list_common_cmds_help();
 702                printf("\n%s\n", _(git_more_info_string));
 703                exit(1);
 704        }
 705        cmd = argv[0];
 706
 707        /*
 708         * We use PATH to find git commands, but we prepend some higher
 709         * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 710         * environment, and the $(gitexecdir) from the Makefile at build
 711         * time.
 712         */
 713        setup_path();
 714
 715        while (1) {
 716                int was_alias = run_argv(&argc, &argv);
 717                if (errno != ENOENT)
 718                        break;
 719                if (was_alias) {
 720                        fprintf(stderr, _("expansion of alias '%s' failed; "
 721                                          "'%s' is not a git command\n"),
 722                                cmd, argv[0]);
 723                        exit(1);
 724                }
 725                if (!done_help) {
 726                        cmd = argv[0] = help_unknown_cmd(cmd);
 727                        done_help = 1;
 728                } else
 729                        break;
 730        }
 731
 732        fprintf(stderr, _("failed to run command '%s': %s\n"),
 733                cmd, strerror(errno));
 734
 735        return 1;
 736}