git.con commit index-pack: use streaming interface for collision test on large blobs (4614043)
   1#include "builtin.h"
   2#include "cache.h"
   3#include "exec_cmd.h"
   4#include "help.h"
   5#include "quote.h"
   6#include "run-command.h"
   7
   8const char git_usage_string[] =
   9        "git [--version] [--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        "           [-c name=value] [--help]\n"
  13        "           <command> [<args>]";
  14
  15const char git_more_info_string[] =
  16        N_("See 'git help <command>' for more information on a specific command.");
  17
  18static struct startup_info git_startup_info;
  19static int use_pager = -1;
  20struct pager_config {
  21        const char *cmd;
  22        int want;
  23        char *value;
  24};
  25
  26static int pager_command_config(const char *var, const char *value, void *data)
  27{
  28        struct pager_config *c = data;
  29        if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd)) {
  30                int b = git_config_maybe_bool(var, value);
  31                if (b >= 0)
  32                        c->want = b;
  33                else {
  34                        c->want = 1;
  35                        c->value = xstrdup(value);
  36                }
  37        }
  38        return 0;
  39}
  40
  41/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  42int check_pager_config(const char *cmd)
  43{
  44        struct pager_config c;
  45        c.cmd = cmd;
  46        c.want = -1;
  47        c.value = NULL;
  48        git_config(pager_command_config, &c);
  49        if (c.value)
  50                pager_program = c.value;
  51        return c.want;
  52}
  53
  54static void commit_pager_choice(void) {
  55        switch (use_pager) {
  56        case 0:
  57                setenv("GIT_PAGER", "cat", 1);
  58                break;
  59        case 1:
  60                setup_pager();
  61                break;
  62        default:
  63                break;
  64        }
  65}
  66
  67static int handle_options(const char ***argv, int *argc, int *envchanged)
  68{
  69        const char **orig_argv = *argv;
  70
  71        while (*argc > 0) {
  72                const char *cmd = (*argv)[0];
  73                if (cmd[0] != '-')
  74                        break;
  75
  76                /*
  77                 * For legacy reasons, the "version" and "help"
  78                 * commands can be written with "--" prepended
  79                 * to make them look like flags.
  80                 */
  81                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  82                        break;
  83
  84                /*
  85                 * Check remaining flags.
  86                 */
  87                if (!prefixcmp(cmd, "--exec-path")) {
  88                        cmd += 11;
  89                        if (*cmd == '=')
  90                                git_set_argv_exec_path(cmd + 1);
  91                        else {
  92                                puts(git_exec_path());
  93                                exit(0);
  94                        }
  95                } else if (!strcmp(cmd, "--html-path")) {
  96                        puts(system_path(GIT_HTML_PATH));
  97                        exit(0);
  98                } else if (!strcmp(cmd, "--man-path")) {
  99                        puts(system_path(GIT_MAN_PATH));
 100                        exit(0);
 101                } else if (!strcmp(cmd, "--info-path")) {
 102                        puts(system_path(GIT_INFO_PATH));
 103                        exit(0);
 104                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 105                        use_pager = 1;
 106                } else if (!strcmp(cmd, "--no-pager")) {
 107                        use_pager = 0;
 108                        if (envchanged)
 109                                *envchanged = 1;
 110                } else if (!strcmp(cmd, "--no-replace-objects")) {
 111                        read_replace_refs = 0;
 112                        setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 113                        if (envchanged)
 114                                *envchanged = 1;
 115                } else if (!strcmp(cmd, "--git-dir")) {
 116                        if (*argc < 2) {
 117                                fprintf(stderr, "No directory given for --git-dir.\n" );
 118                                usage(git_usage_string);
 119                        }
 120                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 121                        if (envchanged)
 122                                *envchanged = 1;
 123                        (*argv)++;
 124                        (*argc)--;
 125                } else if (!prefixcmp(cmd, "--git-dir=")) {
 126                        setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
 127                        if (envchanged)
 128                                *envchanged = 1;
 129                } else if (!strcmp(cmd, "--namespace")) {
 130                        if (*argc < 2) {
 131                                fprintf(stderr, "No namespace given for --namespace.\n" );
 132                                usage(git_usage_string);
 133                        }
 134                        setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 135                        if (envchanged)
 136                                *envchanged = 1;
 137                        (*argv)++;
 138                        (*argc)--;
 139                } else if (!prefixcmp(cmd, "--namespace=")) {
 140                        setenv(GIT_NAMESPACE_ENVIRONMENT, cmd + 12, 1);
 141                        if (envchanged)
 142                                *envchanged = 1;
 143                } else if (!strcmp(cmd, "--work-tree")) {
 144                        if (*argc < 2) {
 145                                fprintf(stderr, "No directory given for --work-tree.\n" );
 146                                usage(git_usage_string);
 147                        }
 148                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 149                        if (envchanged)
 150                                *envchanged = 1;
 151                        (*argv)++;
 152                        (*argc)--;
 153                } else if (!prefixcmp(cmd, "--work-tree=")) {
 154                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 155                        if (envchanged)
 156                                *envchanged = 1;
 157                } else if (!strcmp(cmd, "--bare")) {
 158                        static char git_dir[PATH_MAX+1];
 159                        is_bare_repository_cfg = 1;
 160                        setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
 161                        if (envchanged)
 162                                *envchanged = 1;
 163                } else if (!strcmp(cmd, "-c")) {
 164                        if (*argc < 2) {
 165                                fprintf(stderr, "-c expects a configuration string\n" );
 166                                usage(git_usage_string);
 167                        }
 168                        git_config_push_parameter((*argv)[1]);
 169                        (*argv)++;
 170                        (*argc)--;
 171                } else {
 172                        fprintf(stderr, "Unknown option: %s\n", cmd);
 173                        usage(git_usage_string);
 174                }
 175
 176                (*argv)++;
 177                (*argc)--;
 178        }
 179        return (*argv) - orig_argv;
 180}
 181
 182static int handle_alias(int *argcp, const char ***argv)
 183{
 184        int envchanged = 0, ret = 0, saved_errno = errno;
 185        const char *subdir;
 186        int count, option_count;
 187        const char **new_argv;
 188        const char *alias_command;
 189        char *alias_string;
 190        int unused_nongit;
 191
 192        subdir = setup_git_directory_gently(&unused_nongit);
 193
 194        alias_command = (*argv)[0];
 195        alias_string = alias_lookup(alias_command);
 196        if (alias_string) {
 197                if (alias_string[0] == '!') {
 198                        const char **alias_argv;
 199                        int argc = *argcp, i;
 200
 201                        commit_pager_choice();
 202
 203                        /* build alias_argv */
 204                        alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
 205                        alias_argv[0] = alias_string + 1;
 206                        for (i = 1; i < argc; ++i)
 207                                alias_argv[i] = (*argv)[i];
 208                        alias_argv[argc] = NULL;
 209
 210                        ret = run_command_v_opt(alias_argv, RUN_USING_SHELL);
 211                        if (ret >= 0)   /* normal exit */
 212                                exit(ret);
 213
 214                        die_errno("While expanding alias '%s': '%s'",
 215                            alias_command, alias_string + 1);
 216                }
 217                count = split_cmdline(alias_string, &new_argv);
 218                if (count < 0)
 219                        die("Bad alias.%s string: %s", alias_command,
 220                            split_cmdline_strerror(count));
 221                option_count = handle_options(&new_argv, &count, &envchanged);
 222                if (envchanged)
 223                        die("alias '%s' changes environment variables\n"
 224                                 "You can use '!git' in the alias to do this.",
 225                                 alias_command);
 226                memmove(new_argv - option_count, new_argv,
 227                                count * sizeof(char *));
 228                new_argv -= option_count;
 229
 230                if (count < 1)
 231                        die("empty alias for %s", alias_command);
 232
 233                if (!strcmp(alias_command, new_argv[0]))
 234                        die("recursive alias: %s", alias_command);
 235
 236                trace_argv_printf(new_argv,
 237                                  "trace: alias expansion: %s =>",
 238                                  alias_command);
 239
 240                new_argv = xrealloc(new_argv, sizeof(char *) *
 241                                    (count + *argcp));
 242                /* insert after command name */
 243                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 244
 245                *argv = new_argv;
 246                *argcp += count - 1;
 247
 248                ret = 1;
 249        }
 250
 251        if (subdir && chdir(subdir))
 252                die_errno("Cannot change to '%s'", subdir);
 253
 254        errno = saved_errno;
 255
 256        return ret;
 257}
 258
 259const char git_version_string[] = GIT_VERSION;
 260
 261#define RUN_SETUP               (1<<0)
 262#define RUN_SETUP_GENTLY        (1<<1)
 263#define USE_PAGER               (1<<2)
 264/*
 265 * require working tree to be present -- anything uses this needs
 266 * RUN_SETUP for reading from the configuration file.
 267 */
 268#define NEED_WORK_TREE          (1<<3)
 269
 270struct cmd_struct {
 271        const char *cmd;
 272        int (*fn)(int, const char **, const char *);
 273        int option;
 274};
 275
 276static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 277{
 278        int status, help;
 279        struct stat st;
 280        const char *prefix;
 281
 282        prefix = NULL;
 283        help = argc == 2 && !strcmp(argv[1], "-h");
 284        if (!help) {
 285                if (p->option & RUN_SETUP)
 286                        prefix = setup_git_directory();
 287                if (p->option & RUN_SETUP_GENTLY) {
 288                        int nongit_ok;
 289                        prefix = setup_git_directory_gently(&nongit_ok);
 290                }
 291
 292                if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
 293                        use_pager = check_pager_config(p->cmd);
 294                if (use_pager == -1 && p->option & USE_PAGER)
 295                        use_pager = 1;
 296
 297                if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 298                    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 299                        trace_repo_setup(prefix);
 300        }
 301        commit_pager_choice();
 302
 303        if (!help && p->option & NEED_WORK_TREE)
 304                setup_work_tree();
 305
 306        trace_argv_printf(argv, "trace: built-in: git");
 307
 308        status = p->fn(argc, argv, prefix);
 309        if (status)
 310                return status;
 311
 312        /* Somebody closed stdout? */
 313        if (fstat(fileno(stdout), &st))
 314                return 0;
 315        /* Ignore write errors for pipes and sockets.. */
 316        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 317                return 0;
 318
 319        /* Check for ENOSPC and EIO errors.. */
 320        if (fflush(stdout))
 321                die_errno("write failure on standard output");
 322        if (ferror(stdout))
 323                die("unknown write failure on standard output");
 324        if (fclose(stdout))
 325                die_errno("close failed on standard output");
 326        return 0;
 327}
 328
 329static void handle_internal_command(int argc, const char **argv)
 330{
 331        const char *cmd = argv[0];
 332        static struct cmd_struct commands[] = {
 333                { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 334                { "annotate", cmd_annotate, RUN_SETUP },
 335                { "apply", cmd_apply, RUN_SETUP_GENTLY },
 336                { "archive", cmd_archive },
 337                { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 338                { "blame", cmd_blame, RUN_SETUP },
 339                { "branch", cmd_branch, RUN_SETUP },
 340                { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 341                { "cat-file", cmd_cat_file, RUN_SETUP },
 342                { "check-attr", cmd_check_attr, RUN_SETUP },
 343                { "check-ref-format", cmd_check_ref_format },
 344                { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 345                { "checkout-index", cmd_checkout_index,
 346                        RUN_SETUP | NEED_WORK_TREE},
 347                { "cherry", cmd_cherry, RUN_SETUP },
 348                { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 349                { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 350                { "clone", cmd_clone },
 351                { "column", cmd_column, RUN_SETUP_GENTLY },
 352                { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 353                { "commit-tree", cmd_commit_tree, RUN_SETUP },
 354                { "config", cmd_config, RUN_SETUP_GENTLY },
 355                { "count-objects", cmd_count_objects, RUN_SETUP },
 356                { "describe", cmd_describe, RUN_SETUP },
 357                { "diff", cmd_diff },
 358                { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 359                { "diff-index", cmd_diff_index, RUN_SETUP },
 360                { "diff-tree", cmd_diff_tree, RUN_SETUP },
 361                { "fast-export", cmd_fast_export, RUN_SETUP },
 362                { "fetch", cmd_fetch, RUN_SETUP },
 363                { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 364                { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 365                { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 366                { "format-patch", cmd_format_patch, RUN_SETUP },
 367                { "fsck", cmd_fsck, RUN_SETUP },
 368                { "fsck-objects", cmd_fsck, RUN_SETUP },
 369                { "gc", cmd_gc, RUN_SETUP },
 370                { "get-tar-commit-id", cmd_get_tar_commit_id },
 371                { "grep", cmd_grep, RUN_SETUP_GENTLY },
 372                { "hash-object", cmd_hash_object },
 373                { "help", cmd_help },
 374                { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
 375                { "init", cmd_init_db },
 376                { "init-db", cmd_init_db },
 377                { "log", cmd_log, RUN_SETUP },
 378                { "ls-files", cmd_ls_files, RUN_SETUP },
 379                { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 380                { "ls-tree", cmd_ls_tree, RUN_SETUP },
 381                { "mailinfo", cmd_mailinfo },
 382                { "mailsplit", cmd_mailsplit },
 383                { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 384                { "merge-base", cmd_merge_base, RUN_SETUP },
 385                { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 386                { "merge-index", cmd_merge_index, RUN_SETUP },
 387                { "merge-ours", cmd_merge_ours, RUN_SETUP },
 388                { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 389                { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 390                { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 391                { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 392                { "merge-tree", cmd_merge_tree, RUN_SETUP },
 393                { "mktag", cmd_mktag, RUN_SETUP },
 394                { "mktree", cmd_mktree, RUN_SETUP },
 395                { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 396                { "name-rev", cmd_name_rev, RUN_SETUP },
 397                { "notes", cmd_notes, RUN_SETUP },
 398                { "pack-objects", cmd_pack_objects, RUN_SETUP },
 399                { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
 400                { "pack-refs", cmd_pack_refs, RUN_SETUP },
 401                { "patch-id", cmd_patch_id },
 402                { "peek-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 403                { "pickaxe", cmd_blame, RUN_SETUP },
 404                { "prune", cmd_prune, RUN_SETUP },
 405                { "prune-packed", cmd_prune_packed, RUN_SETUP },
 406                { "push", cmd_push, RUN_SETUP },
 407                { "read-tree", cmd_read_tree, RUN_SETUP },
 408                { "receive-pack", cmd_receive_pack },
 409                { "reflog", cmd_reflog, RUN_SETUP },
 410                { "remote", cmd_remote, RUN_SETUP },
 411                { "remote-ext", cmd_remote_ext },
 412                { "remote-fd", cmd_remote_fd },
 413                { "replace", cmd_replace, RUN_SETUP },
 414                { "repo-config", cmd_repo_config, RUN_SETUP_GENTLY },
 415                { "rerere", cmd_rerere, RUN_SETUP },
 416                { "reset", cmd_reset, RUN_SETUP },
 417                { "rev-list", cmd_rev_list, RUN_SETUP },
 418                { "rev-parse", cmd_rev_parse },
 419                { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 420                { "rm", cmd_rm, RUN_SETUP },
 421                { "send-pack", cmd_send_pack, RUN_SETUP },
 422                { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 423                { "show", cmd_show, RUN_SETUP },
 424                { "show-branch", cmd_show_branch, RUN_SETUP },
 425                { "show-ref", cmd_show_ref, RUN_SETUP },
 426                { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 427                { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 428                { "stripspace", cmd_stripspace },
 429                { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 430                { "tag", cmd_tag, RUN_SETUP },
 431                { "tar-tree", cmd_tar_tree },
 432                { "unpack-file", cmd_unpack_file, RUN_SETUP },
 433                { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 434                { "update-index", cmd_update_index, RUN_SETUP },
 435                { "update-ref", cmd_update_ref, RUN_SETUP },
 436                { "update-server-info", cmd_update_server_info, RUN_SETUP },
 437                { "upload-archive", cmd_upload_archive },
 438                { "upload-archive--writer", cmd_upload_archive_writer },
 439                { "var", cmd_var, RUN_SETUP_GENTLY },
 440                { "verify-pack", cmd_verify_pack },
 441                { "verify-tag", cmd_verify_tag, RUN_SETUP },
 442                { "version", cmd_version },
 443                { "whatchanged", cmd_whatchanged, RUN_SETUP },
 444                { "write-tree", cmd_write_tree, RUN_SETUP },
 445        };
 446        int i;
 447        static const char ext[] = STRIP_EXTENSION;
 448
 449        if (sizeof(ext) > 1) {
 450                i = strlen(argv[0]) - strlen(ext);
 451                if (i > 0 && !strcmp(argv[0] + i, ext)) {
 452                        char *argv0 = xstrdup(argv[0]);
 453                        argv[0] = cmd = argv0;
 454                        argv0[i] = '\0';
 455                }
 456        }
 457
 458        /* Turn "git cmd --help" into "git help cmd" */
 459        if (argc > 1 && !strcmp(argv[1], "--help")) {
 460                argv[1] = argv[0];
 461                argv[0] = cmd = "help";
 462        }
 463
 464        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 465                struct cmd_struct *p = commands+i;
 466                if (strcmp(p->cmd, cmd))
 467                        continue;
 468                exit(run_builtin(p, argc, argv));
 469        }
 470}
 471
 472static void execv_dashed_external(const char **argv)
 473{
 474        struct strbuf cmd = STRBUF_INIT;
 475        const char *tmp;
 476        int status;
 477
 478        if (use_pager == -1)
 479                use_pager = check_pager_config(argv[0]);
 480        commit_pager_choice();
 481
 482        strbuf_addf(&cmd, "git-%s", argv[0]);
 483
 484        /*
 485         * argv[0] must be the git command, but the argv array
 486         * belongs to the caller, and may be reused in
 487         * subsequent loop iterations. Save argv[0] and
 488         * restore it on error.
 489         */
 490        tmp = argv[0];
 491        argv[0] = cmd.buf;
 492
 493        trace_argv_printf(argv, "trace: exec:");
 494
 495        /*
 496         * if we fail because the command is not found, it is
 497         * OK to return. Otherwise, we just pass along the status code.
 498         */
 499        status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE | RUN_CLEAN_ON_EXIT);
 500        if (status >= 0 || errno != ENOENT)
 501                exit(status);
 502
 503        argv[0] = tmp;
 504
 505        strbuf_release(&cmd);
 506}
 507
 508static int run_argv(int *argcp, const char ***argv)
 509{
 510        int done_alias = 0;
 511
 512        while (1) {
 513                /* See if it's an internal command */
 514                handle_internal_command(*argcp, *argv);
 515
 516                /* .. then try the external ones */
 517                execv_dashed_external(*argv);
 518
 519                /* It could be an alias -- this works around the insanity
 520                 * of overriding "git log" with "git show" by having
 521                 * alias.log = show
 522                 */
 523                if (done_alias || !handle_alias(argcp, argv))
 524                        break;
 525                done_alias = 1;
 526        }
 527
 528        return done_alias;
 529}
 530
 531
 532int main(int argc, const char **argv)
 533{
 534        const char *cmd;
 535
 536        startup_info = &git_startup_info;
 537
 538        cmd = git_extract_argv0_path(argv[0]);
 539        if (!cmd)
 540                cmd = "git-help";
 541
 542        git_setup_gettext();
 543
 544        /*
 545         * "git-xxxx" is the same as "git xxxx", but we obviously:
 546         *
 547         *  - cannot take flags in between the "git" and the "xxxx".
 548         *  - cannot execute it externally (since it would just do
 549         *    the same thing over again)
 550         *
 551         * So we just directly call the internal command handler, and
 552         * die if that one cannot handle it.
 553         */
 554        if (!prefixcmp(cmd, "git-")) {
 555                cmd += 4;
 556                argv[0] = cmd;
 557                handle_internal_command(argc, argv);
 558                die("cannot handle %s internally", cmd);
 559        }
 560
 561        /* Look for flags.. */
 562        argv++;
 563        argc--;
 564        handle_options(&argv, &argc, NULL);
 565        if (argc > 0) {
 566                if (!prefixcmp(argv[0], "--"))
 567                        argv[0] += 2;
 568        } else {
 569                /* The user didn't specify a command; give them help */
 570                commit_pager_choice();
 571                printf("usage: %s\n\n", git_usage_string);
 572                list_common_cmds_help();
 573                printf("\n%s\n", git_more_info_string);
 574                exit(1);
 575        }
 576        cmd = argv[0];
 577
 578        /*
 579         * We use PATH to find git commands, but we prepend some higher
 580         * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 581         * environment, and the $(gitexecdir) from the Makefile at build
 582         * time.
 583         */
 584        setup_path();
 585
 586        while (1) {
 587                static int done_help = 0;
 588                static int was_alias = 0;
 589                was_alias = run_argv(&argc, &argv);
 590                if (errno != ENOENT)
 591                        break;
 592                if (was_alias) {
 593                        fprintf(stderr, "Expansion of alias '%s' failed; "
 594                                "'%s' is not a git command\n",
 595                                cmd, argv[0]);
 596                        exit(1);
 597                }
 598                if (!done_help) {
 599                        cmd = argv[0] = help_unknown_cmd(cmd);
 600                        done_help = 1;
 601                } else
 602                        break;
 603        }
 604
 605        fprintf(stderr, "Failed to run command '%s': %s\n",
 606                cmd, strerror(errno));
 607
 608        return 1;
 609}