git.con commit Merge branch 'jc/simplify-progress' into next (9077ff6)
   1#include "builtin.h"
   2#include "config.h"
   3#include "exec_cmd.h"
   4#include "help.h"
   5#include "run-command.h"
   6
   7const char git_usage_string[] =
   8        "git [--version] [--help] [-C <path>] [-c name=value]\n"
   9        "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  10        "           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
  11        "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  12        "           <command> [<args>]";
  13
  14const char git_more_info_string[] =
  15        N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  16           "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  17           "to read about a specific subcommand or concept.");
  18
  19static int use_pager = -1;
  20
  21static void list_builtins(void);
  22
  23static void commit_pager_choice(void) {
  24        switch (use_pager) {
  25        case 0:
  26                setenv("GIT_PAGER", "cat", 1);
  27                break;
  28        case 1:
  29                setup_pager();
  30                break;
  31        default:
  32                break;
  33        }
  34}
  35
  36void setup_auto_pager(const char *cmd, int def)
  37{
  38        if (use_pager != -1 || pager_in_use())
  39                return;
  40        use_pager = check_pager_config(cmd);
  41        if (use_pager == -1)
  42                use_pager = def;
  43        commit_pager_choice();
  44}
  45
  46static int handle_options(const char ***argv, int *argc, int *envchanged)
  47{
  48        const char **orig_argv = *argv;
  49
  50        while (*argc > 0) {
  51                const char *cmd = (*argv)[0];
  52                if (cmd[0] != '-')
  53                        break;
  54
  55                /*
  56                 * For legacy reasons, the "version" and "help"
  57                 * commands can be written with "--" prepended
  58                 * to make them look like flags.
  59                 */
  60                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  61                        break;
  62
  63                /*
  64                 * Check remaining flags.
  65                 */
  66                if (skip_prefix(cmd, "--exec-path", &cmd)) {
  67                        if (*cmd == '=')
  68                                git_set_argv_exec_path(cmd + 1);
  69                        else {
  70                                puts(git_exec_path());
  71                                exit(0);
  72                        }
  73                } else if (!strcmp(cmd, "--html-path")) {
  74                        puts(system_path(GIT_HTML_PATH));
  75                        exit(0);
  76                } else if (!strcmp(cmd, "--man-path")) {
  77                        puts(system_path(GIT_MAN_PATH));
  78                        exit(0);
  79                } else if (!strcmp(cmd, "--info-path")) {
  80                        puts(system_path(GIT_INFO_PATH));
  81                        exit(0);
  82                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  83                        use_pager = 1;
  84                } else if (!strcmp(cmd, "--no-pager")) {
  85                        use_pager = 0;
  86                        if (envchanged)
  87                                *envchanged = 1;
  88                } else if (!strcmp(cmd, "--no-replace-objects")) {
  89                        check_replace_refs = 0;
  90                        setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
  91                        if (envchanged)
  92                                *envchanged = 1;
  93                } else if (!strcmp(cmd, "--git-dir")) {
  94                        if (*argc < 2) {
  95                                fprintf(stderr, "No directory given for --git-dir.\n" );
  96                                usage(git_usage_string);
  97                        }
  98                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
  99                        if (envchanged)
 100                                *envchanged = 1;
 101                        (*argv)++;
 102                        (*argc)--;
 103                } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 104                        setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 105                        if (envchanged)
 106                                *envchanged = 1;
 107                } else if (!strcmp(cmd, "--namespace")) {
 108                        if (*argc < 2) {
 109                                fprintf(stderr, "No namespace given for --namespace.\n" );
 110                                usage(git_usage_string);
 111                        }
 112                        setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 113                        if (envchanged)
 114                                *envchanged = 1;
 115                        (*argv)++;
 116                        (*argc)--;
 117                } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 118                        setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 119                        if (envchanged)
 120                                *envchanged = 1;
 121                } else if (!strcmp(cmd, "--work-tree")) {
 122                        if (*argc < 2) {
 123                                fprintf(stderr, "No directory given for --work-tree.\n" );
 124                                usage(git_usage_string);
 125                        }
 126                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 127                        if (envchanged)
 128                                *envchanged = 1;
 129                        (*argv)++;
 130                        (*argc)--;
 131                } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 132                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 133                        if (envchanged)
 134                                *envchanged = 1;
 135                } else if (!strcmp(cmd, "--super-prefix")) {
 136                        if (*argc < 2) {
 137                                fprintf(stderr, "No prefix given for --super-prefix.\n" );
 138                                usage(git_usage_string);
 139                        }
 140                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 141                        if (envchanged)
 142                                *envchanged = 1;
 143                        (*argv)++;
 144                        (*argc)--;
 145                } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 146                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 147                        if (envchanged)
 148                                *envchanged = 1;
 149                } else if (!strcmp(cmd, "--bare")) {
 150                        char *cwd = xgetcwd();
 151                        is_bare_repository_cfg = 1;
 152                        setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 153                        free(cwd);
 154                        setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 155                        if (envchanged)
 156                                *envchanged = 1;
 157                } else if (!strcmp(cmd, "-c")) {
 158                        if (*argc < 2) {
 159                                fprintf(stderr, "-c expects a configuration string\n" );
 160                                usage(git_usage_string);
 161                        }
 162                        git_config_push_parameter((*argv)[1]);
 163                        (*argv)++;
 164                        (*argc)--;
 165                } else if (!strcmp(cmd, "--literal-pathspecs")) {
 166                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 167                        if (envchanged)
 168                                *envchanged = 1;
 169                } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 170                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 171                        if (envchanged)
 172                                *envchanged = 1;
 173                } else if (!strcmp(cmd, "--glob-pathspecs")) {
 174                        setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 175                        if (envchanged)
 176                                *envchanged = 1;
 177                } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 178                        setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 179                        if (envchanged)
 180                                *envchanged = 1;
 181                } else if (!strcmp(cmd, "--icase-pathspecs")) {
 182                        setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 183                        if (envchanged)
 184                                *envchanged = 1;
 185                } else if (!strcmp(cmd, "--shallow-file")) {
 186                        (*argv)++;
 187                        (*argc)--;
 188                        set_alternate_shallow_file((*argv)[0], 1);
 189                        if (envchanged)
 190                                *envchanged = 1;
 191                } else if (!strcmp(cmd, "-C")) {
 192                        if (*argc < 2) {
 193                                fprintf(stderr, "No directory given for -C.\n" );
 194                                usage(git_usage_string);
 195                        }
 196                        if ((*argv)[1][0]) {
 197                                if (chdir((*argv)[1]))
 198                                        die_errno("Cannot change to '%s'", (*argv)[1]);
 199                                if (envchanged)
 200                                        *envchanged = 1;
 201                        }
 202                        (*argv)++;
 203                        (*argc)--;
 204                } else if (!strcmp(cmd, "--list-builtins")) {
 205                        list_builtins();
 206                        exit(0);
 207                } else {
 208                        fprintf(stderr, "Unknown option: %s\n", cmd);
 209                        usage(git_usage_string);
 210                }
 211
 212                (*argv)++;
 213                (*argc)--;
 214        }
 215        return (*argv) - orig_argv;
 216}
 217
 218static int handle_alias(int *argcp, const char ***argv)
 219{
 220        int envchanged = 0, ret = 0, saved_errno = errno;
 221        int count, option_count;
 222        const char **new_argv;
 223        const char *alias_command;
 224        char *alias_string;
 225
 226        alias_command = (*argv)[0];
 227        alias_string = alias_lookup(alias_command);
 228        if (alias_string) {
 229                if (alias_string[0] == '!') {
 230                        struct child_process child = CHILD_PROCESS_INIT;
 231                        int nongit_ok;
 232
 233                        /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 234                        setup_git_directory_gently(&nongit_ok);
 235
 236                        commit_pager_choice();
 237
 238                        child.use_shell = 1;
 239                        argv_array_push(&child.args, alias_string + 1);
 240                        argv_array_pushv(&child.args, (*argv) + 1);
 241
 242                        ret = run_command(&child);
 243                        if (ret >= 0)   /* normal exit */
 244                                exit(ret);
 245
 246                        die_errno("While expanding alias '%s': '%s'",
 247                            alias_command, alias_string + 1);
 248                }
 249                count = split_cmdline(alias_string, &new_argv);
 250                if (count < 0)
 251                        die("Bad alias.%s string: %s", alias_command,
 252                            split_cmdline_strerror(count));
 253                option_count = handle_options(&new_argv, &count, &envchanged);
 254                if (envchanged)
 255                        die("alias '%s' changes environment variables\n"
 256                                 "You can use '!git' in the alias to do this.",
 257                                 alias_command);
 258                memmove(new_argv - option_count, new_argv,
 259                                count * sizeof(char *));
 260                new_argv -= option_count;
 261
 262                if (count < 1)
 263                        die("empty alias for %s", alias_command);
 264
 265                if (!strcmp(alias_command, new_argv[0]))
 266                        die("recursive alias: %s", alias_command);
 267
 268                trace_argv_printf(new_argv,
 269                                  "trace: alias expansion: %s =>",
 270                                  alias_command);
 271
 272                REALLOC_ARRAY(new_argv, count + *argcp);
 273                /* insert after command name */
 274                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 275
 276                *argv = new_argv;
 277                *argcp += count - 1;
 278
 279                ret = 1;
 280        }
 281
 282        errno = saved_errno;
 283
 284        return ret;
 285}
 286
 287#define RUN_SETUP               (1<<0)
 288#define RUN_SETUP_GENTLY        (1<<1)
 289#define USE_PAGER               (1<<2)
 290/*
 291 * require working tree to be present -- anything uses this needs
 292 * RUN_SETUP for reading from the configuration file.
 293 */
 294#define NEED_WORK_TREE          (1<<3)
 295#define SUPPORT_SUPER_PREFIX    (1<<4)
 296#define DELAY_PAGER_CONFIG      (1<<5)
 297
 298struct cmd_struct {
 299        const char *cmd;
 300        int (*fn)(int, const char **, const char *);
 301        int option;
 302};
 303
 304static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 305{
 306        int status, help;
 307        struct stat st;
 308        const char *prefix;
 309
 310        prefix = NULL;
 311        help = argc == 2 && !strcmp(argv[1], "-h");
 312        if (!help) {
 313                if (p->option & RUN_SETUP)
 314                        prefix = setup_git_directory();
 315                else if (p->option & RUN_SETUP_GENTLY) {
 316                        int nongit_ok;
 317                        prefix = setup_git_directory_gently(&nongit_ok);
 318                }
 319
 320                if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
 321                    !(p->option & DELAY_PAGER_CONFIG))
 322                        use_pager = check_pager_config(p->cmd);
 323                if (use_pager == -1 && p->option & USE_PAGER)
 324                        use_pager = 1;
 325
 326                if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 327                    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 328                        trace_repo_setup(prefix);
 329        }
 330        commit_pager_choice();
 331
 332        if (!help && get_super_prefix()) {
 333                if (!(p->option & SUPPORT_SUPER_PREFIX))
 334                        die("%s doesn't support --super-prefix", p->cmd);
 335        }
 336
 337        if (!help && p->option & NEED_WORK_TREE)
 338                setup_work_tree();
 339
 340        trace_argv_printf(argv, "trace: built-in: git");
 341
 342        status = p->fn(argc, argv, prefix);
 343        if (status)
 344                return status;
 345
 346        /* Somebody closed stdout? */
 347        if (fstat(fileno(stdout), &st))
 348                return 0;
 349        /* Ignore write errors for pipes and sockets.. */
 350        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 351                return 0;
 352
 353        /* Check for ENOSPC and EIO errors.. */
 354        if (fflush(stdout))
 355                die_errno("write failure on standard output");
 356        if (ferror(stdout))
 357                die("unknown write failure on standard output");
 358        if (fclose(stdout))
 359                die_errno("close failed on standard output");
 360        return 0;
 361}
 362
 363static struct cmd_struct commands[] = {
 364        { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 365        { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 366        { "annotate", cmd_annotate, RUN_SETUP },
 367        { "apply", cmd_apply, RUN_SETUP_GENTLY },
 368        { "archive", cmd_archive, RUN_SETUP_GENTLY },
 369        { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 370        { "blame", cmd_blame, RUN_SETUP },
 371        { "branch", cmd_branch, RUN_SETUP },
 372        { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 373        { "cat-file", cmd_cat_file, RUN_SETUP },
 374        { "check-attr", cmd_check_attr, RUN_SETUP },
 375        { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 376        { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 377        { "check-ref-format", cmd_check_ref_format },
 378        { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 379        { "checkout-index", cmd_checkout_index,
 380                RUN_SETUP | NEED_WORK_TREE},
 381        { "cherry", cmd_cherry, RUN_SETUP },
 382        { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 383        { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 384        { "clone", cmd_clone },
 385        { "column", cmd_column, RUN_SETUP_GENTLY },
 386        { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 387        { "commit-tree", cmd_commit_tree, RUN_SETUP },
 388        { "config", cmd_config, RUN_SETUP_GENTLY },
 389        { "count-objects", cmd_count_objects, RUN_SETUP },
 390        { "credential", cmd_credential, RUN_SETUP_GENTLY },
 391        { "describe", cmd_describe, RUN_SETUP },
 392        { "diff", cmd_diff },
 393        { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 394        { "diff-index", cmd_diff_index, RUN_SETUP },
 395        { "diff-tree", cmd_diff_tree, RUN_SETUP },
 396        { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 397        { "fast-export", cmd_fast_export, RUN_SETUP },
 398        { "fetch", cmd_fetch, RUN_SETUP },
 399        { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 400        { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 401        { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 402        { "format-patch", cmd_format_patch, RUN_SETUP },
 403        { "fsck", cmd_fsck, RUN_SETUP },
 404        { "fsck-objects", cmd_fsck, RUN_SETUP },
 405        { "gc", cmd_gc, RUN_SETUP },
 406        { "get-tar-commit-id", cmd_get_tar_commit_id },
 407        { "grep", cmd_grep, RUN_SETUP_GENTLY },
 408        { "hash-object", cmd_hash_object },
 409        { "help", cmd_help },
 410        { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
 411        { "init", cmd_init_db },
 412        { "init-db", cmd_init_db },
 413        { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 414        { "log", cmd_log, RUN_SETUP },
 415        { "ls-files", cmd_ls_files, RUN_SETUP },
 416        { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 417        { "ls-tree", cmd_ls_tree, RUN_SETUP },
 418        { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },
 419        { "mailsplit", cmd_mailsplit },
 420        { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 421        { "merge-base", cmd_merge_base, RUN_SETUP },
 422        { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 423        { "merge-index", cmd_merge_index, RUN_SETUP },
 424        { "merge-ours", cmd_merge_ours, RUN_SETUP },
 425        { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 426        { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 427        { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 428        { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 429        { "merge-tree", cmd_merge_tree, RUN_SETUP },
 430        { "mktag", cmd_mktag, RUN_SETUP },
 431        { "mktree", cmd_mktree, RUN_SETUP },
 432        { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 433        { "name-rev", cmd_name_rev, RUN_SETUP },
 434        { "notes", cmd_notes, RUN_SETUP },
 435        { "pack-objects", cmd_pack_objects, RUN_SETUP },
 436        { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
 437        { "pack-refs", cmd_pack_refs, RUN_SETUP },
 438        { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY },
 439        { "pickaxe", cmd_blame, RUN_SETUP },
 440        { "prune", cmd_prune, RUN_SETUP },
 441        { "prune-packed", cmd_prune_packed, RUN_SETUP },
 442        { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 443        { "push", cmd_push, RUN_SETUP },
 444        { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 445        { "rebase--helper", cmd_rebase__helper, RUN_SETUP | NEED_WORK_TREE },
 446        { "receive-pack", cmd_receive_pack },
 447        { "reflog", cmd_reflog, RUN_SETUP },
 448        { "remote", cmd_remote, RUN_SETUP },
 449        { "remote-ext", cmd_remote_ext },
 450        { "remote-fd", cmd_remote_fd },
 451        { "repack", cmd_repack, RUN_SETUP },
 452        { "replace", cmd_replace, RUN_SETUP },
 453        { "rerere", cmd_rerere, RUN_SETUP },
 454        { "reset", cmd_reset, RUN_SETUP },
 455        { "rev-list", cmd_rev_list, RUN_SETUP },
 456        { "rev-parse", cmd_rev_parse },
 457        { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 458        { "rm", cmd_rm, RUN_SETUP },
 459        { "send-pack", cmd_send_pack, RUN_SETUP },
 460        { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 461        { "show", cmd_show, RUN_SETUP },
 462        { "show-branch", cmd_show_branch, RUN_SETUP },
 463        { "show-ref", cmd_show_ref, RUN_SETUP },
 464        { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 465        { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 466        { "stripspace", cmd_stripspace },
 467        { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 468        { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 469        { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 470        { "unpack-file", cmd_unpack_file, RUN_SETUP },
 471        { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 472        { "update-index", cmd_update_index, RUN_SETUP },
 473        { "update-ref", cmd_update_ref, RUN_SETUP },
 474        { "update-server-info", cmd_update_server_info, RUN_SETUP },
 475        { "upload-archive", cmd_upload_archive },
 476        { "upload-archive--writer", cmd_upload_archive_writer },
 477        { "var", cmd_var, RUN_SETUP_GENTLY },
 478        { "verify-commit", cmd_verify_commit, RUN_SETUP },
 479        { "verify-pack", cmd_verify_pack },
 480        { "verify-tag", cmd_verify_tag, RUN_SETUP },
 481        { "version", cmd_version },
 482        { "whatchanged", cmd_whatchanged, RUN_SETUP },
 483        { "worktree", cmd_worktree, RUN_SETUP },
 484        { "write-tree", cmd_write_tree, RUN_SETUP },
 485};
 486
 487static struct cmd_struct *get_builtin(const char *s)
 488{
 489        int i;
 490        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 491                struct cmd_struct *p = commands + i;
 492                if (!strcmp(s, p->cmd))
 493                        return p;
 494        }
 495        return NULL;
 496}
 497
 498int is_builtin(const char *s)
 499{
 500        return !!get_builtin(s);
 501}
 502
 503static void list_builtins(void)
 504{
 505        int i;
 506        for (i = 0; i < ARRAY_SIZE(commands); i++)
 507                printf("%s\n", commands[i].cmd);
 508}
 509
 510#ifdef STRIP_EXTENSION
 511static void strip_extension(const char **argv)
 512{
 513        size_t len;
 514
 515        if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 516                argv[0] = xmemdupz(argv[0], len);
 517}
 518#else
 519#define strip_extension(cmd)
 520#endif
 521
 522static void handle_builtin(int argc, const char **argv)
 523{
 524        struct argv_array args = ARGV_ARRAY_INIT;
 525        const char *cmd;
 526        struct cmd_struct *builtin;
 527
 528        strip_extension(argv);
 529        cmd = argv[0];
 530
 531        /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 532        if (argc > 1 && !strcmp(argv[1], "--help")) {
 533                int i;
 534
 535                argv[1] = argv[0];
 536                argv[0] = cmd = "help";
 537
 538                for (i = 0; i < argc; i++) {
 539                        argv_array_push(&args, argv[i]);
 540                        if (!i)
 541                                argv_array_push(&args, "--exclude-guides");
 542                }
 543
 544                argc++;
 545                argv = args.argv;
 546        }
 547
 548        builtin = get_builtin(cmd);
 549        if (builtin)
 550                exit(run_builtin(builtin, argc, argv));
 551        argv_array_clear(&args);
 552}
 553
 554static void execv_dashed_external(const char **argv)
 555{
 556        struct child_process cmd = CHILD_PROCESS_INIT;
 557        int status;
 558
 559        if (get_super_prefix())
 560                die("%s doesn't support --super-prefix", argv[0]);
 561
 562        if (use_pager == -1 && !is_builtin(argv[0]))
 563                use_pager = check_pager_config(argv[0]);
 564        commit_pager_choice();
 565
 566        argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 567        argv_array_pushv(&cmd.args, argv + 1);
 568        cmd.clean_on_exit = 1;
 569        cmd.wait_after_clean = 1;
 570        cmd.silent_exec_failure = 1;
 571
 572        trace_argv_printf(cmd.args.argv, "trace: exec:");
 573
 574        /*
 575         * If we fail because the command is not found, it is
 576         * OK to return. Otherwise, we just pass along the status code,
 577         * or our usual generic code if we were not even able to exec
 578         * the program.
 579         */
 580        status = run_command(&cmd);
 581        if (status >= 0)
 582                exit(status);
 583        else if (errno != ENOENT)
 584                exit(128);
 585}
 586
 587static int run_argv(int *argcp, const char ***argv)
 588{
 589        int done_alias = 0;
 590
 591        while (1) {
 592                /*
 593                 * If we tried alias and futzed with our environment,
 594                 * it no longer is safe to invoke builtins directly in
 595                 * general.  We have to spawn them as dashed externals.
 596                 *
 597                 * NEEDSWORK: if we can figure out cases
 598                 * where it is safe to do, we can avoid spawning a new
 599                 * process.
 600                 */
 601                if (!done_alias)
 602                        handle_builtin(*argcp, *argv);
 603
 604                /* .. then try the external ones */
 605                execv_dashed_external(*argv);
 606
 607                /* It could be an alias -- this works around the insanity
 608                 * of overriding "git log" with "git show" by having
 609                 * alias.log = show
 610                 */
 611                if (done_alias)
 612                        break;
 613                if (!handle_alias(argcp, argv))
 614                        break;
 615                done_alias = 1;
 616        }
 617
 618        return done_alias;
 619}
 620
 621int cmd_main(int argc, const char **argv)
 622{
 623        const char *cmd;
 624        int done_help = 0;
 625
 626        cmd = argv[0];
 627        if (!cmd)
 628                cmd = "git-help";
 629        else {
 630                const char *slash = find_last_dir_sep(cmd);
 631                if (slash)
 632                        cmd = slash + 1;
 633        }
 634
 635        trace_command_performance(argv);
 636
 637        /*
 638         * "git-xxxx" is the same as "git xxxx", but we obviously:
 639         *
 640         *  - cannot take flags in between the "git" and the "xxxx".
 641         *  - cannot execute it externally (since it would just do
 642         *    the same thing over again)
 643         *
 644         * So we just directly call the builtin handler, and die if
 645         * that one cannot handle it.
 646         */
 647        if (skip_prefix(cmd, "git-", &cmd)) {
 648                argv[0] = cmd;
 649                handle_builtin(argc, argv);
 650                die("cannot handle %s as a builtin", cmd);
 651        }
 652
 653        /* Look for flags.. */
 654        argv++;
 655        argc--;
 656        handle_options(&argv, &argc, NULL);
 657        if (argc > 0) {
 658                /* translate --help and --version into commands */
 659                skip_prefix(argv[0], "--", &argv[0]);
 660        } else {
 661                /* The user didn't specify a command; give them help */
 662                commit_pager_choice();
 663                printf("usage: %s\n\n", git_usage_string);
 664                list_common_cmds_help();
 665                printf("\n%s\n", _(git_more_info_string));
 666                exit(1);
 667        }
 668        cmd = argv[0];
 669
 670        /*
 671         * We use PATH to find git commands, but we prepend some higher
 672         * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 673         * environment, and the $(gitexecdir) from the Makefile at build
 674         * time.
 675         */
 676        setup_path();
 677
 678        while (1) {
 679                int was_alias = run_argv(&argc, &argv);
 680                if (errno != ENOENT)
 681                        break;
 682                if (was_alias) {
 683                        fprintf(stderr, "Expansion of alias '%s' failed; "
 684                                "'%s' is not a git command\n",
 685                                cmd, argv[0]);
 686                        exit(1);
 687                }
 688                if (!done_help) {
 689                        cmd = argv[0] = help_unknown_cmd(cmd);
 690                        done_help = 1;
 691                } else
 692                        break;
 693        }
 694
 695        fprintf(stderr, "Failed to run command '%s': %s\n",
 696                cmd, strerror(errno));
 697
 698        return 1;
 699}