fetch-pack: refactor parsing in get_ack
[git] / git.c
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 #include "commit.h"
8
9 const char git_usage_string[] =
10         "git [--version] [--help] [-C <path>] [-c name=value]\n"
11         "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
12         "           [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]\n"
13         "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
14         "           <command> [<args>]";
15
16 const char git_more_info_string[] =
17         N_("'git help -a' and 'git help -g' lists available subcommands and some\n"
18            "concept guides. See 'git help <command>' or 'git help <concept>'\n"
19            "to read about a specific subcommand or concept.");
20
21 static struct startup_info git_startup_info;
22 static int use_pager = -1;
23
24 static void commit_pager_choice(void) {
25         switch (use_pager) {
26         case 0:
27                 setenv("GIT_PAGER", "cat", 1);
28                 break;
29         case 1:
30                 setup_pager();
31                 break;
32         default:
33                 break;
34         }
35 }
36
37 static int handle_options(const char ***argv, int *argc, int *envchanged)
38 {
39         const char **orig_argv = *argv;
40
41         while (*argc > 0) {
42                 const char *cmd = (*argv)[0];
43                 if (cmd[0] != '-')
44                         break;
45
46                 /*
47                  * For legacy reasons, the "version" and "help"
48                  * commands can be written with "--" prepended
49                  * to make them look like flags.
50                  */
51                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
52                         break;
53
54                 /*
55                  * Check remaining flags.
56                  */
57                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
58                         if (*cmd == '=')
59                                 git_set_argv_exec_path(cmd + 1);
60                         else {
61                                 puts(git_exec_path());
62                                 exit(0);
63                         }
64                 } else if (!strcmp(cmd, "--html-path")) {
65                         puts(system_path(GIT_HTML_PATH));
66                         exit(0);
67                 } else if (!strcmp(cmd, "--man-path")) {
68                         puts(system_path(GIT_MAN_PATH));
69                         exit(0);
70                 } else if (!strcmp(cmd, "--info-path")) {
71                         puts(system_path(GIT_INFO_PATH));
72                         exit(0);
73                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
74                         use_pager = 1;
75                 } else if (!strcmp(cmd, "--no-pager")) {
76                         use_pager = 0;
77                         if (envchanged)
78                                 *envchanged = 1;
79                 } else if (!strcmp(cmd, "--no-replace-objects")) {
80                         check_replace_refs = 0;
81                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
82                         if (envchanged)
83                                 *envchanged = 1;
84                 } else if (!strcmp(cmd, "--git-dir")) {
85                         if (*argc < 2) {
86                                 fprintf(stderr, "No directory given for --git-dir.\n" );
87                                 usage(git_usage_string);
88                         }
89                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
90                         if (envchanged)
91                                 *envchanged = 1;
92                         (*argv)++;
93                         (*argc)--;
94                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
95                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
96                         if (envchanged)
97                                 *envchanged = 1;
98                 } else if (!strcmp(cmd, "--namespace")) {
99                         if (*argc < 2) {
100                                 fprintf(stderr, "No namespace given for --namespace.\n" );
101                                 usage(git_usage_string);
102                         }
103                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
104                         if (envchanged)
105                                 *envchanged = 1;
106                         (*argv)++;
107                         (*argc)--;
108                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
109                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
110                         if (envchanged)
111                                 *envchanged = 1;
112                 } else if (!strcmp(cmd, "--work-tree")) {
113                         if (*argc < 2) {
114                                 fprintf(stderr, "No directory given for --work-tree.\n" );
115                                 usage(git_usage_string);
116                         }
117                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
118                         if (envchanged)
119                                 *envchanged = 1;
120                         (*argv)++;
121                         (*argc)--;
122                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
123                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
124                         if (envchanged)
125                                 *envchanged = 1;
126                 } else if (!strcmp(cmd, "--bare")) {
127                         static char git_dir[PATH_MAX+1];
128                         is_bare_repository_cfg = 1;
129                         setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
130                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
131                         if (envchanged)
132                                 *envchanged = 1;
133                 } else if (!strcmp(cmd, "-c")) {
134                         if (*argc < 2) {
135                                 fprintf(stderr, "-c expects a configuration string\n" );
136                                 usage(git_usage_string);
137                         }
138                         git_config_push_parameter((*argv)[1]);
139                         (*argv)++;
140                         (*argc)--;
141                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
142                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
143                         if (envchanged)
144                                 *envchanged = 1;
145                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
146                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
147                         if (envchanged)
148                                 *envchanged = 1;
149                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
150                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
151                         if (envchanged)
152                                 *envchanged = 1;
153                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
154                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
155                         if (envchanged)
156                                 *envchanged = 1;
157                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
158                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
159                         if (envchanged)
160                                 *envchanged = 1;
161                 } else if (!strcmp(cmd, "--shallow-file")) {
162                         (*argv)++;
163                         (*argc)--;
164                         set_alternate_shallow_file((*argv)[0], 1);
165                         if (envchanged)
166                                 *envchanged = 1;
167                 } else if (!strcmp(cmd, "-C")) {
168                         if (*argc < 2) {
169                                 fprintf(stderr, "No directory given for -C.\n" );
170                                 usage(git_usage_string);
171                         }
172                         if (chdir((*argv)[1]))
173                                 die_errno("Cannot change to '%s'", (*argv)[1]);
174                         if (envchanged)
175                                 *envchanged = 1;
176                         (*argv)++;
177                         (*argc)--;
178                 } else {
179                         fprintf(stderr, "Unknown option: %s\n", cmd);
180                         usage(git_usage_string);
181                 }
182
183                 (*argv)++;
184                 (*argc)--;
185         }
186         return (*argv) - orig_argv;
187 }
188
189 static int handle_alias(int *argcp, const char ***argv)
190 {
191         int envchanged = 0, ret = 0, saved_errno = errno;
192         const char *subdir;
193         int count, option_count;
194         const char **new_argv;
195         const char *alias_command;
196         char *alias_string;
197         int unused_nongit;
198
199         subdir = setup_git_directory_gently(&unused_nongit);
200
201         alias_command = (*argv)[0];
202         alias_string = alias_lookup(alias_command);
203         if (alias_string) {
204                 if (alias_string[0] == '!') {
205                         const char **alias_argv;
206                         int argc = *argcp, i;
207
208                         commit_pager_choice();
209
210                         /* build alias_argv */
211                         alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
212                         alias_argv[0] = alias_string + 1;
213                         for (i = 1; i < argc; ++i)
214                                 alias_argv[i] = (*argv)[i];
215                         alias_argv[argc] = NULL;
216
217                         ret = run_command_v_opt(alias_argv, RUN_USING_SHELL);
218                         if (ret >= 0)   /* normal exit */
219                                 exit(ret);
220
221                         die_errno("While expanding alias '%s': '%s'",
222                             alias_command, alias_string + 1);
223                 }
224                 count = split_cmdline(alias_string, &new_argv);
225                 if (count < 0)
226                         die("Bad alias.%s string: %s", alias_command,
227                             split_cmdline_strerror(count));
228                 option_count = handle_options(&new_argv, &count, &envchanged);
229                 if (envchanged)
230                         die("alias '%s' changes environment variables\n"
231                                  "You can use '!git' in the alias to do this.",
232                                  alias_command);
233                 memmove(new_argv - option_count, new_argv,
234                                 count * sizeof(char *));
235                 new_argv -= option_count;
236
237                 if (count < 1)
238                         die("empty alias for %s", alias_command);
239
240                 if (!strcmp(alias_command, new_argv[0]))
241                         die("recursive alias: %s", alias_command);
242
243                 trace_argv_printf(new_argv,
244                                   "trace: alias expansion: %s =>",
245                                   alias_command);
246
247                 new_argv = xrealloc(new_argv, sizeof(char *) *
248                                     (count + *argcp));
249                 /* insert after command name */
250                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
251
252                 *argv = new_argv;
253                 *argcp += count - 1;
254
255                 ret = 1;
256         }
257
258         if (subdir && chdir(subdir))
259                 die_errno("Cannot change to '%s'", subdir);
260
261         errno = saved_errno;
262
263         return ret;
264 }
265
266 #define RUN_SETUP               (1<<0)
267 #define RUN_SETUP_GENTLY        (1<<1)
268 #define USE_PAGER               (1<<2)
269 /*
270  * require working tree to be present -- anything uses this needs
271  * RUN_SETUP for reading from the configuration file.
272  */
273 #define NEED_WORK_TREE          (1<<3)
274
275 struct cmd_struct {
276         const char *cmd;
277         int (*fn)(int, const char **, const char *);
278         int option;
279 };
280
281 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
282 {
283         int status, help;
284         struct stat st;
285         const char *prefix;
286
287         prefix = NULL;
288         help = argc == 2 && !strcmp(argv[1], "-h");
289         if (!help) {
290                 if (p->option & RUN_SETUP)
291                         prefix = setup_git_directory();
292                 else if (p->option & RUN_SETUP_GENTLY) {
293                         int nongit_ok;
294                         prefix = setup_git_directory_gently(&nongit_ok);
295                 }
296
297                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
298                         use_pager = check_pager_config(p->cmd);
299                 if (use_pager == -1 && p->option & USE_PAGER)
300                         use_pager = 1;
301
302                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
303                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
304                         trace_repo_setup(prefix);
305         }
306         commit_pager_choice();
307
308         if (!help && p->option & NEED_WORK_TREE)
309                 setup_work_tree();
310
311         trace_argv_printf(argv, "trace: built-in: git");
312
313         status = p->fn(argc, argv, prefix);
314         if (status)
315                 return status;
316
317         /* Somebody closed stdout? */
318         if (fstat(fileno(stdout), &st))
319                 return 0;
320         /* Ignore write errors for pipes and sockets.. */
321         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
322                 return 0;
323
324         /* Check for ENOSPC and EIO errors.. */
325         if (fflush(stdout))
326                 die_errno("write failure on standard output");
327         if (ferror(stdout))
328                 die("unknown write failure on standard output");
329         if (fclose(stdout))
330                 die_errno("close failed on standard output");
331         return 0;
332 }
333
334 static struct cmd_struct commands[] = {
335         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
336         { "annotate", cmd_annotate, RUN_SETUP },
337         { "apply", cmd_apply, RUN_SETUP_GENTLY },
338         { "archive", cmd_archive },
339         { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
340         { "blame", cmd_blame, RUN_SETUP },
341         { "branch", cmd_branch, RUN_SETUP },
342         { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
343         { "cat-file", cmd_cat_file, RUN_SETUP },
344         { "check-attr", cmd_check_attr, RUN_SETUP },
345         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
346         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
347         { "check-ref-format", cmd_check_ref_format },
348         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
349         { "checkout-index", cmd_checkout_index,
350                 RUN_SETUP | NEED_WORK_TREE},
351         { "cherry", cmd_cherry, RUN_SETUP },
352         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
353         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
354         { "clone", cmd_clone },
355         { "column", cmd_column, RUN_SETUP_GENTLY },
356         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
357         { "commit-tree", cmd_commit_tree, RUN_SETUP },
358         { "config", cmd_config, RUN_SETUP_GENTLY },
359         { "count-objects", cmd_count_objects, RUN_SETUP },
360         { "credential", cmd_credential, RUN_SETUP_GENTLY },
361         { "describe", cmd_describe, RUN_SETUP },
362         { "diff", cmd_diff },
363         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
364         { "diff-index", cmd_diff_index, RUN_SETUP },
365         { "diff-tree", cmd_diff_tree, RUN_SETUP },
366         { "fast-export", cmd_fast_export, RUN_SETUP },
367         { "fetch", cmd_fetch, RUN_SETUP },
368         { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
369         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
370         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
371         { "format-patch", cmd_format_patch, RUN_SETUP },
372         { "fsck", cmd_fsck, RUN_SETUP },
373         { "fsck-objects", cmd_fsck, RUN_SETUP },
374         { "gc", cmd_gc, RUN_SETUP },
375         { "get-tar-commit-id", cmd_get_tar_commit_id },
376         { "grep", cmd_grep, RUN_SETUP_GENTLY },
377         { "hash-object", cmd_hash_object },
378         { "help", cmd_help },
379         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
380         { "init", cmd_init_db },
381         { "init-db", cmd_init_db },
382         { "log", cmd_log, RUN_SETUP },
383         { "ls-files", cmd_ls_files, RUN_SETUP },
384         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
385         { "ls-tree", cmd_ls_tree, RUN_SETUP },
386         { "mailinfo", cmd_mailinfo },
387         { "mailsplit", cmd_mailsplit },
388         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
389         { "merge-base", cmd_merge_base, RUN_SETUP },
390         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
391         { "merge-index", cmd_merge_index, RUN_SETUP },
392         { "merge-ours", cmd_merge_ours, RUN_SETUP },
393         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
394         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
395         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
396         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
397         { "merge-tree", cmd_merge_tree, RUN_SETUP },
398         { "mktag", cmd_mktag, RUN_SETUP },
399         { "mktree", cmd_mktree, RUN_SETUP },
400         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
401         { "name-rev", cmd_name_rev, RUN_SETUP },
402         { "notes", cmd_notes, RUN_SETUP },
403         { "pack-objects", cmd_pack_objects, RUN_SETUP },
404         { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
405         { "pack-refs", cmd_pack_refs, RUN_SETUP },
406         { "patch-id", cmd_patch_id },
407         { "pickaxe", cmd_blame, RUN_SETUP },
408         { "prune", cmd_prune, RUN_SETUP },
409         { "prune-packed", cmd_prune_packed, RUN_SETUP },
410         { "push", cmd_push, RUN_SETUP },
411         { "read-tree", cmd_read_tree, RUN_SETUP },
412         { "receive-pack", cmd_receive_pack },
413         { "reflog", cmd_reflog, RUN_SETUP },
414         { "remote", cmd_remote, RUN_SETUP },
415         { "remote-ext", cmd_remote_ext },
416         { "remote-fd", cmd_remote_fd },
417         { "repack", cmd_repack, RUN_SETUP },
418         { "replace", cmd_replace, RUN_SETUP },
419         { "rerere", cmd_rerere, RUN_SETUP },
420         { "reset", cmd_reset, RUN_SETUP },
421         { "rev-list", cmd_rev_list, RUN_SETUP },
422         { "rev-parse", cmd_rev_parse },
423         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
424         { "rm", cmd_rm, RUN_SETUP },
425         { "send-pack", cmd_send_pack, RUN_SETUP },
426         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
427         { "show", cmd_show, RUN_SETUP },
428         { "show-branch", cmd_show_branch, RUN_SETUP },
429         { "show-ref", cmd_show_ref, RUN_SETUP },
430         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
431         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
432         { "stripspace", cmd_stripspace },
433         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
434         { "tag", cmd_tag, RUN_SETUP },
435         { "unpack-file", cmd_unpack_file, RUN_SETUP },
436         { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
437         { "update-index", cmd_update_index, RUN_SETUP },
438         { "update-ref", cmd_update_ref, RUN_SETUP },
439         { "update-server-info", cmd_update_server_info, RUN_SETUP },
440         { "upload-archive", cmd_upload_archive },
441         { "upload-archive--writer", cmd_upload_archive_writer },
442         { "var", cmd_var, RUN_SETUP_GENTLY },
443         { "verify-pack", cmd_verify_pack },
444         { "verify-tag", cmd_verify_tag, RUN_SETUP },
445         { "version", cmd_version },
446         { "whatchanged", cmd_whatchanged, RUN_SETUP },
447         { "write-tree", cmd_write_tree, RUN_SETUP },
448 };
449
450 int is_builtin(const char *s)
451 {
452         int i;
453         for (i = 0; i < ARRAY_SIZE(commands); i++) {
454                 struct cmd_struct *p = commands+i;
455                 if (!strcmp(s, p->cmd))
456                         return 1;
457         }
458         return 0;
459 }
460
461 static void handle_builtin(int argc, const char **argv)
462 {
463         const char *cmd = argv[0];
464         int i;
465         static const char ext[] = STRIP_EXTENSION;
466
467         if (sizeof(ext) > 1) {
468                 i = strlen(argv[0]) - strlen(ext);
469                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
470                         char *argv0 = xstrdup(argv[0]);
471                         argv[0] = cmd = argv0;
472                         argv0[i] = '\0';
473                 }
474         }
475
476         /* Turn "git cmd --help" into "git help cmd" */
477         if (argc > 1 && !strcmp(argv[1], "--help")) {
478                 argv[1] = argv[0];
479                 argv[0] = cmd = "help";
480         }
481
482         for (i = 0; i < ARRAY_SIZE(commands); i++) {
483                 struct cmd_struct *p = commands+i;
484                 if (strcmp(p->cmd, cmd))
485                         continue;
486                 exit(run_builtin(p, argc, argv));
487         }
488 }
489
490 static void execv_dashed_external(const char **argv)
491 {
492         struct strbuf cmd = STRBUF_INIT;
493         const char *tmp;
494         int status;
495
496         if (use_pager == -1)
497                 use_pager = check_pager_config(argv[0]);
498         commit_pager_choice();
499
500         strbuf_addf(&cmd, "git-%s", argv[0]);
501
502         /*
503          * argv[0] must be the git command, but the argv array
504          * belongs to the caller, and may be reused in
505          * subsequent loop iterations. Save argv[0] and
506          * restore it on error.
507          */
508         tmp = argv[0];
509         argv[0] = cmd.buf;
510
511         trace_argv_printf(argv, "trace: exec:");
512
513         /*
514          * if we fail because the command is not found, it is
515          * OK to return. Otherwise, we just pass along the status code.
516          */
517         status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE | RUN_CLEAN_ON_EXIT);
518         if (status >= 0 || errno != ENOENT)
519                 exit(status);
520
521         argv[0] = tmp;
522
523         strbuf_release(&cmd);
524 }
525
526 static int run_argv(int *argcp, const char ***argv)
527 {
528         int done_alias = 0;
529
530         while (1) {
531                 /* See if it's a builtin */
532                 handle_builtin(*argcp, *argv);
533
534                 /* .. then try the external ones */
535                 execv_dashed_external(*argv);
536
537                 /* It could be an alias -- this works around the insanity
538                  * of overriding "git log" with "git show" by having
539                  * alias.log = show
540                  */
541                 if (done_alias || !handle_alias(argcp, argv))
542                         break;
543                 done_alias = 1;
544         }
545
546         return done_alias;
547 }
548
549
550 int main(int argc, char **av)
551 {
552         const char **argv = (const char **) av;
553         const char *cmd;
554
555         startup_info = &git_startup_info;
556
557         cmd = git_extract_argv0_path(argv[0]);
558         if (!cmd)
559                 cmd = "git-help";
560
561         /*
562          * Always open file descriptors 0/1/2 to avoid clobbering files
563          * in die().  It also avoids messing up when the pipes are dup'ed
564          * onto stdin/stdout/stderr in the child processes we spawn.
565          */
566         sanitize_stdfds();
567
568         git_setup_gettext();
569
570         /*
571          * "git-xxxx" is the same as "git xxxx", but we obviously:
572          *
573          *  - cannot take flags in between the "git" and the "xxxx".
574          *  - cannot execute it externally (since it would just do
575          *    the same thing over again)
576          *
577          * So we just directly call the builtin handler, and die if
578          * that one cannot handle it.
579          */
580         if (skip_prefix(cmd, "git-", &cmd)) {
581                 argv[0] = cmd;
582                 handle_builtin(argc, argv);
583                 die("cannot handle %s as a builtin", cmd);
584         }
585
586         /* Look for flags.. */
587         argv++;
588         argc--;
589         handle_options(&argv, &argc, NULL);
590         if (argc > 0) {
591                 if (starts_with(argv[0], "--"))
592                         argv[0] += 2;
593         } else {
594                 /* The user didn't specify a command; give them help */
595                 commit_pager_choice();
596                 printf("usage: %s\n\n", git_usage_string);
597                 list_common_cmds_help();
598                 printf("\n%s\n", _(git_more_info_string));
599                 exit(1);
600         }
601         cmd = argv[0];
602
603         /*
604          * We use PATH to find git commands, but we prepend some higher
605          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
606          * environment, and the $(gitexecdir) from the Makefile at build
607          * time.
608          */
609         setup_path();
610
611         while (1) {
612                 static int done_help = 0;
613                 static int was_alias = 0;
614                 was_alias = run_argv(&argc, &argv);
615                 if (errno != ENOENT)
616                         break;
617                 if (was_alias) {
618                         fprintf(stderr, "Expansion of alias '%s' failed; "
619                                 "'%s' is not a git command\n",
620                                 cmd, argv[0]);
621                         exit(1);
622                 }
623                 if (!done_help) {
624                         cmd = argv[0] = help_unknown_cmd(cmd);
625                         done_help = 1;
626                 } else
627                         break;
628         }
629
630         fprintf(stderr, "Failed to run command '%s': %s\n",
631                 cmd, strerror(errno));
632
633         return 1;
634 }