Andrew's git / gitweb.git / git.c
?
git.con commit git-p4: raise exceptions from p4CmdList based on error from p4 server (55bb3e3)
   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 void commit_pager_choice(void) {
  42        switch (use_pager) {
  43        case 0:
  44                setenv("GIT_PAGER", "cat", 1);
  45                break;
  46        case 1:
  47                setup_pager();
  48                break;
  49        default:
  50                break;
  51        }
  52}
  53
  54void setup_auto_pager(const char *cmd, int def)
  55{
  56        if (use_pager != -1 || pager_in_use())
  57                return;
  58        use_pager = check_pager_config(cmd);
  59        if (use_pager == -1)
  60                use_pager = def;
  61        commit_pager_choice();
  62}
  63
  64static int handle_options(const char ***argv, int *argc, int *envchanged)
  65{
  66        const char **orig_argv = *argv;
  67
  68        while (*argc > 0) {
  69                const char *cmd = (*argv)[0];
  70                if (cmd[0] != '-')
  71                        break;
  72
  73                /*
  74                 * For legacy reasons, the "version" and "help"
  75                 * commands can be written with "--" prepended
  76                 * to make them look like flags.
  77                 */
  78                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  79                        break;
  80
  81                /*
  82                 * Check remaining flags.
  83                 */
  84                if (skip_prefix(cmd, "--exec-path", &cmd)) {
  85                        if (*cmd == '=')
  86                                git_set_exec_path(cmd + 1);
  87                        else {
  88                                puts(git_exec_path());
  89                                exit(0);
  90                        }
  91                } else if (!strcmp(cmd, "--html-path")) {
  92                        puts(system_path(GIT_HTML_PATH));
  93                        exit(0);
  94                } else if (!strcmp(cmd, "--man-path")) {
  95                        puts(system_path(GIT_MAN_PATH));
  96                        exit(0);
  97                } else if (!strcmp(cmd, "--info-path")) {
  98                        puts(system_path(GIT_INFO_PATH));
  99                        exit(0);
 100                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 101                        use_pager = 1;
 102                } else if (!strcmp(cmd, "--no-pager")) {
 103                        use_pager = 0;
 104                        if (envchanged)
 105                                *envchanged = 1;
 106                } else if (!strcmp(cmd, "--no-replace-objects")) {
 107                        check_replace_refs = 0;
 108                        setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 109                        if (envchanged)
 110                                *envchanged = 1;
 111                } else if (!strcmp(cmd, "--git-dir")) {
 112                        if (*argc < 2) {
 113                                fprintf(stderr, _("no directory given for --git-dir\n" ));
 114                                usage(git_usage_string);
 115                        }
 116                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 117                        if (envchanged)
 118                                *envchanged = 1;
 119                        (*argv)++;
 120                        (*argc)--;
 121                } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 122                        setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 123                        if (envchanged)
 124                                *envchanged = 1;
 125                } else if (!strcmp(cmd, "--namespace")) {
 126                        if (*argc < 2) {
 127                                fprintf(stderr, _("no namespace given for --namespace\n" ));
 128                                usage(git_usage_string);
 129                        }
 130                        setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 131                        if (envchanged)
 132                                *envchanged = 1;
 133                        (*argv)++;
 134                        (*argc)--;
 135                } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 136                        setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 137                        if (envchanged)
 138                                *envchanged = 1;
 139                } else if (!strcmp(cmd, "--work-tree")) {
 140                        if (*argc < 2) {
 141                                fprintf(stderr, _("no directory given for --work-tree\n" ));
 142                                usage(git_usage_string);
 143                        }
 144                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 145                        if (envchanged)
 146                                *envchanged = 1;
 147                        (*argv)++;
 148                        (*argc)--;
 149                } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 150                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 151                        if (envchanged)
 152                                *envchanged = 1;
 153                } else if (!strcmp(cmd, "--super-prefix")) {
 154                        if (*argc < 2) {
 155                                fprintf(stderr, _("no prefix given for --super-prefix\n" ));
 156                                usage(git_usage_string);
 157                        }
 158                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 159                        if (envchanged)
 160                                *envchanged = 1;
 161                        (*argv)++;
 162                        (*argc)--;
 163                } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 164                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 165                        if (envchanged)
 166                                *envchanged = 1;
 167                } else if (!strcmp(cmd, "--bare")) {
 168                        char *cwd = xgetcwd();
 169                        is_bare_repository_cfg = 1;
 170                        setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 171                        free(cwd);
 172                        setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 173                        if (envchanged)
 174                                *envchanged = 1;
 175                } else if (!strcmp(cmd, "-c")) {
 176                        if (*argc < 2) {
 177                                fprintf(stderr, _("-c expects a configuration string\n" ));
 178                                usage(git_usage_string);
 179                        }
 180                        git_config_push_parameter((*argv)[1]);
 181                        (*argv)++;
 182                        (*argc)--;
 183                } else if (!strcmp(cmd, "--literal-pathspecs")) {
 184                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 185                        if (envchanged)
 186                                *envchanged = 1;
 187                } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 188                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 189                        if (envchanged)
 190                                *envchanged = 1;
 191                } else if (!strcmp(cmd, "--glob-pathspecs")) {
 192                        setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 193                        if (envchanged)
 194                                *envchanged = 1;
 195                } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 196                        setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 197                        if (envchanged)
 198                                *envchanged = 1;
 199                } else if (!strcmp(cmd, "--icase-pathspecs")) {
 200                        setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 201                        if (envchanged)
 202                                *envchanged = 1;
 203                } else if (!strcmp(cmd, "--no-optional-locks")) {
 204                        setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 205                        if (envchanged)
 206                                *envchanged = 1;
 207                } else if (!strcmp(cmd, "--shallow-file")) {
 208                        (*argv)++;
 209                        (*argc)--;
 210                        set_alternate_shallow_file((*argv)[0], 1);
 211                        if (envchanged)
 212                                *envchanged = 1;
 213                } else if (!strcmp(cmd, "-C")) {
 214                        if (*argc < 2) {
 215                                fprintf(stderr, _("no directory given for -C\n" ));
 216                                usage(git_usage_string);
 217                        }
 218                        if ((*argv)[1][0]) {
 219                                if (chdir((*argv)[1]))
 220                                        die_errno("cannot change to '%s'", (*argv)[1]);
 221                                if (envchanged)
 222                                        *envchanged = 1;
 223                        }
 224                        (*argv)++;
 225                        (*argc)--;
 226                } else if (!strcmp(cmd, "--list-builtins")) {
 227                        list_builtins(0, '\n');
 228                        exit(0);
 229                } else if (!strcmp(cmd, "--list-parseopt-builtins")) {
 230                        list_builtins(NO_PARSEOPT, ' ');
 231                        exit(0);
 232                } else {
 233                        fprintf(stderr, _("unknown option: %s\n"), cmd);
 234                        usage(git_usage_string);
 235                }
 236
 237                (*argv)++;
 238                (*argc)--;
 239        }
 240        return (*argv) - orig_argv;
 241}
 242
 243static int handle_alias(int *argcp, const char ***argv)
 244{
 245        int envchanged = 0, ret = 0, saved_errno = errno;
 246        int count, option_count;
 247        const char **new_argv;
 248        const char *alias_command;
 249        char *alias_string;
 250
 251        alias_command = (*argv)[0];
 252        alias_string = alias_lookup(alias_command);
 253        if (alias_string) {
 254                if (alias_string[0] == '!') {
 255                        struct child_process child = CHILD_PROCESS_INIT;
 256                        int nongit_ok;
 257
 258                        /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 259                        setup_git_directory_gently(&nongit_ok);
 260
 261                        commit_pager_choice();
 262
 263                        child.use_shell = 1;
 264                        argv_array_push(&child.args, alias_string + 1);
 265                        argv_array_pushv(&child.args, (*argv) + 1);
 266
 267                        ret = run_command(&child);
 268                        if (ret >= 0)   /* normal exit */
 269                                exit(ret);
 270
 271                        die_errno("while expanding alias '%s': '%s'",
 272                            alias_command, alias_string + 1);
 273                }
 274                count = split_cmdline(alias_string, &new_argv);
 275                if (count < 0)
 276                        die("Bad alias.%s string: %s", alias_command,
 277                            split_cmdline_strerror(count));
 278                option_count = handle_options(&new_argv, &count, &envchanged);
 279                if (envchanged)
 280                        die("alias '%s' changes environment variables.\n"
 281                                 "You can use '!git' in the alias to do this",
 282                                 alias_command);
 283                memmove(new_argv - option_count, new_argv,
 284                                count * sizeof(char *));
 285                new_argv -= option_count;
 286
 287                if (count < 1)
 288                        die("empty alias for %s", alias_command);
 289
 290                if (!strcmp(alias_command, new_argv[0]))
 291                        die("recursive alias: %s", alias_command);
 292
 293                trace_argv_printf(new_argv,
 294                                  "trace: alias expansion: %s =>",
 295                                  alias_command);
 296
 297                REALLOC_ARRAY(new_argv, count + *argcp);
 298                /* insert after command name */
 299                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 300
 301                *argv = new_argv;
 302                *argcp += count - 1;
 303
 304                ret = 1;
 305        }
 306
 307        errno = saved_errno;
 308
 309        return ret;
 310}
 311
 312static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 313{
 314        int status, help;
 315        struct stat st;
 316        const char *prefix;
 317
 318        prefix = NULL;
 319        help = argc == 2 && !strcmp(argv[1], "-h");
 320        if (!help) {
 321                if (p->option & RUN_SETUP)
 322                        prefix = setup_git_directory();
 323                else if (p->option & RUN_SETUP_GENTLY) {
 324                        int nongit_ok;
 325                        prefix = setup_git_directory_gently(&nongit_ok);
 326                }
 327
 328                if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
 329                    !(p->option & DELAY_PAGER_CONFIG))
 330                        use_pager = check_pager_config(p->cmd);
 331                if (use_pager == -1 && p->option & USE_PAGER)
 332                        use_pager = 1;
 333
 334                if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 335                    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 336                        trace_repo_setup(prefix);
 337        }
 338        commit_pager_choice();
 339
 340        if (!help && get_super_prefix()) {
 341                if (!(p->option & SUPPORT_SUPER_PREFIX))
 342                        die("%s doesn't support --super-prefix", p->cmd);
 343        }
 344
 345        if (!help && p->option & NEED_WORK_TREE)
 346                setup_work_tree();
 347
 348        trace_argv_printf(argv, "trace: built-in: git");
 349
 350        status = p->fn(argc, argv, prefix);
 351        if (status)
 352                return status;
 353
 354        /* Somebody closed stdout? */
 355        if (fstat(fileno(stdout), &st))
 356                return 0;
 357        /* Ignore write errors for pipes and sockets.. */
 358        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 359                return 0;
 360
 361        /* Check for ENOSPC and EIO errors.. */
 362        if (fflush(stdout))
 363                die_errno("write failure on standard output");
 364        if (ferror(stdout))
 365                die("unknown write failure on standard output");
 366        if (fclose(stdout))
 367                die_errno("close failed on standard output");
 368        return 0;
 369}
 370
 371static struct cmd_struct commands[] = {
 372        { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 373        { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 374        { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
 375        { "apply", cmd_apply, RUN_SETUP_GENTLY },
 376        { "archive", cmd_archive, RUN_SETUP_GENTLY },
 377        { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 378        { "blame", cmd_blame, RUN_SETUP },
 379        { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 380        { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
 381        { "cat-file", cmd_cat_file, RUN_SETUP },
 382        { "check-attr", cmd_check_attr, RUN_SETUP },
 383        { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 384        { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 385        { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 386        { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 387        { "checkout-index", cmd_checkout_index,
 388                RUN_SETUP | NEED_WORK_TREE},
 389        { "cherry", cmd_cherry, RUN_SETUP },
 390        { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 391        { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 392        { "clone", cmd_clone },
 393        { "column", cmd_column, RUN_SETUP_GENTLY },
 394        { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 395        { "commit-graph", cmd_commit_graph, RUN_SETUP },
 396        { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
 397        { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 398        { "count-objects", cmd_count_objects, RUN_SETUP },
 399        { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 400        { "describe", cmd_describe, RUN_SETUP },
 401        { "diff", cmd_diff, NO_PARSEOPT },
 402        { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 403        { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 404        { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 405        { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 406        { "fast-export", cmd_fast_export, RUN_SETUP },
 407        { "fetch", cmd_fetch, RUN_SETUP },
 408        { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 409        { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 410        { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 411        { "format-patch", cmd_format_patch, RUN_SETUP },
 412        { "fsck", cmd_fsck, RUN_SETUP },
 413        { "fsck-objects", cmd_fsck, RUN_SETUP },
 414        { "gc", cmd_gc, RUN_SETUP },
 415        { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 416        { "grep", cmd_grep, RUN_SETUP_GENTLY },
 417        { "hash-object", cmd_hash_object },
 418        { "help", cmd_help },
 419        { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 420        { "init", cmd_init_db },
 421        { "init-db", cmd_init_db },
 422        { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 423        { "log", cmd_log, RUN_SETUP },
 424        { "ls-files", cmd_ls_files, RUN_SETUP },
 425        { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 426        { "ls-tree", cmd_ls_tree, RUN_SETUP },
 427        { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
 428        { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 429        { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 430        { "merge-base", cmd_merge_base, RUN_SETUP },
 431        { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 432        { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 433        { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 434        { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 435        { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 436        { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 437        { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 438        { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
 439        { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
 440        { "mktree", cmd_mktree, RUN_SETUP },
 441        { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 442        { "name-rev", cmd_name_rev, RUN_SETUP },
 443        { "notes", cmd_notes, RUN_SETUP },
 444        { "pack-objects", cmd_pack_objects, RUN_SETUP },
 445        { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 446        { "pack-refs", cmd_pack_refs, RUN_SETUP },
 447        { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 448        { "pickaxe", cmd_blame, RUN_SETUP },
 449        { "prune", cmd_prune, RUN_SETUP },
 450        { "prune-packed", cmd_prune_packed, RUN_SETUP },
 451        { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 452        { "push", cmd_push, RUN_SETUP },
 453        { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 454        { "rebase--helper", cmd_rebase__helper, RUN_SETUP | NEED_WORK_TREE },
 455        { "receive-pack", cmd_receive_pack },
 456        { "reflog", cmd_reflog, RUN_SETUP },
 457        { "remote", cmd_remote, RUN_SETUP },
 458        { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 459        { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 460        { "repack", cmd_repack, RUN_SETUP },
 461        { "replace", cmd_replace, RUN_SETUP },
 462        { "rerere", cmd_rerere, RUN_SETUP },
 463        { "reset", cmd_reset, RUN_SETUP },
 464        { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 465        { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 466        { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 467        { "rm", cmd_rm, RUN_SETUP },
 468        { "send-pack", cmd_send_pack, RUN_SETUP },
 469        { "serve", cmd_serve, RUN_SETUP },
 470        { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 471        { "show", cmd_show, RUN_SETUP },
 472        { "show-branch", cmd_show_branch, RUN_SETUP },
 473        { "show-ref", cmd_show_ref, RUN_SETUP },
 474        { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 475        { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 476        { "stripspace", cmd_stripspace },
 477        { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
 478        { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 479        { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 480        { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 481        { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 482        { "update-index", cmd_update_index, RUN_SETUP },
 483        { "update-ref", cmd_update_ref, RUN_SETUP },
 484        { "update-server-info", cmd_update_server_info, RUN_SETUP },
 485        { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 486        { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 487        { "upload-pack", cmd_upload_pack },
 488        { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 489        { "verify-commit", cmd_verify_commit, RUN_SETUP },
 490        { "verify-pack", cmd_verify_pack },
 491        { "verify-tag", cmd_verify_tag, RUN_SETUP },
 492        { "version", cmd_version },
 493        { "whatchanged", cmd_whatchanged, RUN_SETUP },
 494        { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
 495        { "write-tree", cmd_write_tree, RUN_SETUP },
 496};
 497
 498static struct cmd_struct *get_builtin(const char *s)
 499{
 500        int i;
 501        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 502                struct cmd_struct *p = commands + i;
 503                if (!strcmp(s, p->cmd))
 504                        return p;
 505        }
 506        return NULL;
 507}
 508
 509int is_builtin(const char *s)
 510{
 511        return !!get_builtin(s);
 512}
 513
 514static void list_builtins(unsigned int exclude_option, char sep)
 515{
 516        int i;
 517        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 518                if (exclude_option &&
 519                    (commands[i].option & exclude_option))
 520                        continue;
 521                printf("%s%c", commands[i].cmd, sep);
 522        }
 523}
 524
 525#ifdef STRIP_EXTENSION
 526static void strip_extension(const char **argv)
 527{
 528        size_t len;
 529
 530        if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 531                argv[0] = xmemdupz(argv[0], len);
 532}
 533#else
 534#define strip_extension(cmd)
 535#endif
 536
 537static void handle_builtin(int argc, const char **argv)
 538{
 539        struct argv_array args = ARGV_ARRAY_INIT;
 540        const char *cmd;
 541        struct cmd_struct *builtin;
 542
 543        strip_extension(argv);
 544        cmd = argv[0];
 545
 546        /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 547        if (argc > 1 && !strcmp(argv[1], "--help")) {
 548                int i;
 549
 550                argv[1] = argv[0];
 551                argv[0] = cmd = "help";
 552
 553                for (i = 0; i < argc; i++) {
 554                        argv_array_push(&args, argv[i]);
 555                        if (!i)
 556                                argv_array_push(&args, "--exclude-guides");
 557                }
 558
 559                argc++;
 560                argv = args.argv;
 561        }
 562
 563        builtin = get_builtin(cmd);
 564        if (builtin)
 565                exit(run_builtin(builtin, argc, argv));
 566        argv_array_clear(&args);
 567}
 568
 569static void execv_dashed_external(const char **argv)
 570{
 571        struct child_process cmd = CHILD_PROCESS_INIT;
 572        int status;
 573
 574        if (get_super_prefix())
 575                die("%s doesn't support --super-prefix", argv[0]);
 576
 577        if (use_pager == -1 && !is_builtin(argv[0]))
 578                use_pager = check_pager_config(argv[0]);
 579        commit_pager_choice();
 580
 581        argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 582        argv_array_pushv(&cmd.args, argv + 1);
 583        cmd.clean_on_exit = 1;
 584        cmd.wait_after_clean = 1;
 585        cmd.silent_exec_failure = 1;
 586
 587        trace_argv_printf(cmd.args.argv, "trace: exec:");
 588
 589        /*
 590         * If we fail because the command is not found, it is
 591         * OK to return. Otherwise, we just pass along the status code,
 592         * or our usual generic code if we were not even able to exec
 593         * the program.
 594         */
 595        status = run_command(&cmd);
 596        if (status >= 0)
 597                exit(status);
 598        else if (errno != ENOENT)
 599                exit(128);
 600}
 601
 602static int run_argv(int *argcp, const char ***argv)
 603{
 604        int done_alias = 0;
 605
 606        while (1) {
 607                /*
 608                 * If we tried alias and futzed with our environment,
 609                 * it no longer is safe to invoke builtins directly in
 610                 * general.  We have to spawn them as dashed externals.
 611                 *
 612                 * NEEDSWORK: if we can figure out cases
 613                 * where it is safe to do, we can avoid spawning a new
 614                 * process.
 615                 */
 616                if (!done_alias)
 617                        handle_builtin(*argcp, *argv);
 618
 619                /* .. then try the external ones */
 620                execv_dashed_external(*argv);
 621
 622                /* It could be an alias -- this works around the insanity
 623                 * of overriding "git log" with "git show" by having
 624                 * alias.log = show
 625                 */
 626                if (done_alias)
 627                        break;
 628                if (!handle_alias(argcp, argv))
 629                        break;
 630                done_alias = 1;
 631        }
 632
 633        return done_alias;
 634}
 635
 636int cmd_main(int argc, const char **argv)
 637{
 638        const char *cmd;
 639        int done_help = 0;
 640
 641        cmd = argv[0];
 642        if (!cmd)
 643                cmd = "git-help";
 644        else {
 645                const char *slash = find_last_dir_sep(cmd);
 646                if (slash)
 647                        cmd = slash + 1;
 648        }
 649
 650        trace_command_performance(argv);
 651
 652        /*
 653         * "git-xxxx" is the same as "git xxxx", but we obviously:
 654         *
 655         *  - cannot take flags in between the "git" and the "xxxx".
 656         *  - cannot execute it externally (since it would just do
 657         *    the same thing over again)
 658         *
 659         * So we just directly call the builtin handler, and die if
 660         * that one cannot handle it.
 661         */
 662        if (skip_prefix(cmd, "git-", &cmd)) {
 663                argv[0] = cmd;
 664                handle_builtin(argc, argv);
 665                die("cannot handle %s as a builtin", cmd);
 666        }
 667
 668        /* Look for flags.. */
 669        argv++;
 670        argc--;
 671        handle_options(&argv, &argc, NULL);
 672        if (argc > 0) {
 673                /* translate --help and --version into commands */
 674                skip_prefix(argv[0], "--", &argv[0]);
 675        } else {
 676                /* The user didn't specify a command; give them help */
 677                commit_pager_choice();
 678                printf("usage: %s\n\n", git_usage_string);
 679                list_common_cmds_help();
 680                printf("\n%s\n", _(git_more_info_string));
 681                exit(1);
 682        }
 683        cmd = argv[0];
 684
 685        /*
 686         * We use PATH to find git commands, but we prepend some higher
 687         * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 688         * environment, and the $(gitexecdir) from the Makefile at build
 689         * time.
 690         */
 691        setup_path();
 692
 693        while (1) {
 694                int was_alias = run_argv(&argc, &argv);
 695                if (errno != ENOENT)
 696                        break;
 697                if (was_alias) {
 698                        fprintf(stderr, _("expansion of alias '%s' failed; "
 699                                          "'%s' is not a git command\n"),
 700                                cmd, argv[0]);
 701                        exit(1);
 702                }
 703                if (!done_help) {
 704                        cmd = argv[0] = help_unknown_cmd(cmd);
 705                        done_help = 1;
 706                } else
 707                        break;
 708        }
 709
 710        fprintf(stderr, _("failed to run command '%s': %s\n"),
 711                cmd, strerror(errno));
 712
 713        return 1;
 714}