git-completion.bash: pass $__git_subcommand_idx from __git_main()
[git] / git.c
1 #include "builtin.h"
2 #include "config.h"
3 #include "exec-cmd.h"
4 #include "help.h"
5 #include "run-command.h"
6 #include "alias.h"
7 #include "shallow.h"
8
9 #define RUN_SETUP               (1<<0)
10 #define RUN_SETUP_GENTLY        (1<<1)
11 #define USE_PAGER               (1<<2)
12 /*
13  * require working tree to be present -- anything uses this needs
14  * RUN_SETUP for reading from the configuration file.
15  */
16 #define NEED_WORK_TREE          (1<<3)
17 #define SUPPORT_SUPER_PREFIX    (1<<4)
18 #define DELAY_PAGER_CONFIG      (1<<5)
19 #define NO_PARSEOPT             (1<<6) /* parse-options is not used */
20
21 struct cmd_struct {
22         const char *cmd;
23         int (*fn)(int, const char **, const char *);
24         unsigned int option;
25 };
26
27 const char git_usage_string[] =
28         N_("git [--version] [--help] [-C <path>] [-c <name>=<value>]\n"
29            "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
30            "           [-p | --paginate | -P | --no-pager] [--no-replace-objects] [--bare]\n"
31            "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
32            "           [--super-prefix=<path>] [--config-env=<name>=<envvar>]\n"
33            "           <command> [<args>]");
34
35 const char git_more_info_string[] =
36         N_("'git help -a' and 'git help -g' list available subcommands and some\n"
37            "concept guides. See 'git help <command>' or 'git help <concept>'\n"
38            "to read about a specific subcommand or concept.\n"
39            "See 'git help git' for an overview of the system.");
40
41 static int use_pager = -1;
42
43 static void list_builtins(struct string_list *list, unsigned int exclude_option);
44
45 static void exclude_helpers_from_list(struct string_list *list)
46 {
47         int i = 0;
48
49         while (i < list->nr) {
50                 if (strstr(list->items[i].string, "--"))
51                         unsorted_string_list_delete_item(list, i, 0);
52                 else
53                         i++;
54         }
55 }
56
57 static int match_token(const char *spec, int len, const char *token)
58 {
59         int token_len = strlen(token);
60
61         return len == token_len && !strncmp(spec, token, token_len);
62 }
63
64 static int list_cmds(const char *spec)
65 {
66         struct string_list list = STRING_LIST_INIT_DUP;
67         int i;
68         int nongit;
69
70         /*
71         * Set up the repository so we can pick up any repo-level config (like
72         * completion.commands).
73         */
74         setup_git_directory_gently(&nongit);
75
76         while (*spec) {
77                 const char *sep = strchrnul(spec, ',');
78                 int len = sep - spec;
79
80                 if (match_token(spec, len, "builtins"))
81                         list_builtins(&list, 0);
82                 else if (match_token(spec, len, "main"))
83                         list_all_main_cmds(&list);
84                 else if (match_token(spec, len, "others"))
85                         list_all_other_cmds(&list);
86                 else if (match_token(spec, len, "nohelpers"))
87                         exclude_helpers_from_list(&list);
88                 else if (match_token(spec, len, "alias"))
89                         list_aliases(&list);
90                 else if (match_token(spec, len, "config"))
91                         list_cmds_by_config(&list);
92                 else if (len > 5 && !strncmp(spec, "list-", 5)) {
93                         struct strbuf sb = STRBUF_INIT;
94
95                         strbuf_add(&sb, spec + 5, len - 5);
96                         list_cmds_by_category(&list, sb.buf);
97                         strbuf_release(&sb);
98                 }
99                 else
100                         die(_("unsupported command listing type '%s'"), spec);
101                 spec += len;
102                 if (*spec == ',')
103                         spec++;
104         }
105         for (i = 0; i < list.nr; i++)
106                 puts(list.items[i].string);
107         string_list_clear(&list, 0);
108         return 0;
109 }
110
111 static void commit_pager_choice(void)
112 {
113         switch (use_pager) {
114         case 0:
115                 setenv("GIT_PAGER", "cat", 1);
116                 break;
117         case 1:
118                 setup_pager();
119                 break;
120         default:
121                 break;
122         }
123 }
124
125 void setup_auto_pager(const char *cmd, int def)
126 {
127         if (use_pager != -1 || pager_in_use())
128                 return;
129         use_pager = check_pager_config(cmd);
130         if (use_pager == -1)
131                 use_pager = def;
132         commit_pager_choice();
133 }
134
135 static int handle_options(const char ***argv, int *argc, int *envchanged)
136 {
137         const char **orig_argv = *argv;
138
139         while (*argc > 0) {
140                 const char *cmd = (*argv)[0];
141                 if (cmd[0] != '-')
142                         break;
143
144                 /*
145                  * For legacy reasons, the "version" and "help"
146                  * commands can be written with "--" prepended
147                  * to make them look like flags.
148                  */
149                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
150                         break;
151
152                 /*
153                  * Check remaining flags.
154                  */
155                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
156                         if (*cmd == '=')
157                                 git_set_exec_path(cmd + 1);
158                         else {
159                                 puts(git_exec_path());
160                                 trace2_cmd_name("_query_");
161                                 exit(0);
162                         }
163                 } else if (!strcmp(cmd, "--html-path")) {
164                         puts(system_path(GIT_HTML_PATH));
165                         trace2_cmd_name("_query_");
166                         exit(0);
167                 } else if (!strcmp(cmd, "--man-path")) {
168                         puts(system_path(GIT_MAN_PATH));
169                         trace2_cmd_name("_query_");
170                         exit(0);
171                 } else if (!strcmp(cmd, "--info-path")) {
172                         puts(system_path(GIT_INFO_PATH));
173                         trace2_cmd_name("_query_");
174                         exit(0);
175                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
176                         use_pager = 1;
177                 } else if (!strcmp(cmd, "-P") || !strcmp(cmd, "--no-pager")) {
178                         use_pager = 0;
179                         if (envchanged)
180                                 *envchanged = 1;
181                 } else if (!strcmp(cmd, "--no-replace-objects")) {
182                         read_replace_refs = 0;
183                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
184                         if (envchanged)
185                                 *envchanged = 1;
186                 } else if (!strcmp(cmd, "--git-dir")) {
187                         if (*argc < 2) {
188                                 fprintf(stderr, _("no directory given for --git-dir\n" ));
189                                 usage(git_usage_string);
190                         }
191                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
192                         if (envchanged)
193                                 *envchanged = 1;
194                         (*argv)++;
195                         (*argc)--;
196                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
197                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
198                         if (envchanged)
199                                 *envchanged = 1;
200                 } else if (!strcmp(cmd, "--namespace")) {
201                         if (*argc < 2) {
202                                 fprintf(stderr, _("no namespace given for --namespace\n" ));
203                                 usage(git_usage_string);
204                         }
205                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
206                         if (envchanged)
207                                 *envchanged = 1;
208                         (*argv)++;
209                         (*argc)--;
210                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
211                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
212                         if (envchanged)
213                                 *envchanged = 1;
214                 } else if (!strcmp(cmd, "--work-tree")) {
215                         if (*argc < 2) {
216                                 fprintf(stderr, _("no directory given for --work-tree\n" ));
217                                 usage(git_usage_string);
218                         }
219                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
220                         if (envchanged)
221                                 *envchanged = 1;
222                         (*argv)++;
223                         (*argc)--;
224                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
225                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
226                         if (envchanged)
227                                 *envchanged = 1;
228                 } else if (!strcmp(cmd, "--super-prefix")) {
229                         if (*argc < 2) {
230                                 fprintf(stderr, _("no prefix given for --super-prefix\n" ));
231                                 usage(git_usage_string);
232                         }
233                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
234                         if (envchanged)
235                                 *envchanged = 1;
236                         (*argv)++;
237                         (*argc)--;
238                 } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
239                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
240                         if (envchanged)
241                                 *envchanged = 1;
242                 } else if (!strcmp(cmd, "--bare")) {
243                         char *cwd = xgetcwd();
244                         is_bare_repository_cfg = 1;
245                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
246                         free(cwd);
247                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
248                         if (envchanged)
249                                 *envchanged = 1;
250                 } else if (!strcmp(cmd, "-c")) {
251                         if (*argc < 2) {
252                                 fprintf(stderr, _("-c expects a configuration string\n" ));
253                                 usage(git_usage_string);
254                         }
255                         git_config_push_parameter((*argv)[1]);
256                         (*argv)++;
257                         (*argc)--;
258                 } else if (skip_prefix(cmd, "--config-env=", &cmd)) {
259                         git_config_push_env(cmd);
260                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
261                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
262                         if (envchanged)
263                                 *envchanged = 1;
264                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
265                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
266                         if (envchanged)
267                                 *envchanged = 1;
268                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
269                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
270                         if (envchanged)
271                                 *envchanged = 1;
272                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
273                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
274                         if (envchanged)
275                                 *envchanged = 1;
276                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
277                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
278                         if (envchanged)
279                                 *envchanged = 1;
280                 } else if (!strcmp(cmd, "--no-optional-locks")) {
281                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
282                         if (envchanged)
283                                 *envchanged = 1;
284                 } else if (!strcmp(cmd, "--shallow-file")) {
285                         (*argv)++;
286                         (*argc)--;
287                         set_alternate_shallow_file(the_repository, (*argv)[0], 1);
288                         if (envchanged)
289                                 *envchanged = 1;
290                 } else if (!strcmp(cmd, "-C")) {
291                         if (*argc < 2) {
292                                 fprintf(stderr, _("no directory given for -C\n" ));
293                                 usage(git_usage_string);
294                         }
295                         if ((*argv)[1][0]) {
296                                 if (chdir((*argv)[1]))
297                                         die_errno("cannot change to '%s'", (*argv)[1]);
298                                 if (envchanged)
299                                         *envchanged = 1;
300                         }
301                         (*argv)++;
302                         (*argc)--;
303                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
304                         trace2_cmd_name("_query_");
305                         if (!strcmp(cmd, "parseopt")) {
306                                 struct string_list list = STRING_LIST_INIT_DUP;
307                                 int i;
308
309                                 list_builtins(&list, NO_PARSEOPT);
310                                 for (i = 0; i < list.nr; i++)
311                                         printf("%s ", list.items[i].string);
312                                 string_list_clear(&list, 0);
313                                 exit(0);
314                         } else {
315                                 exit(list_cmds(cmd));
316                         }
317                 } else {
318                         fprintf(stderr, _("unknown option: %s\n"), cmd);
319                         usage(git_usage_string);
320                 }
321
322                 (*argv)++;
323                 (*argc)--;
324         }
325         return (*argv) - orig_argv;
326 }
327
328 static int handle_alias(int *argcp, const char ***argv)
329 {
330         int envchanged = 0, ret = 0, saved_errno = errno;
331         int count, option_count;
332         const char **new_argv;
333         const char *alias_command;
334         char *alias_string;
335
336         alias_command = (*argv)[0];
337         alias_string = alias_lookup(alias_command);
338         if (alias_string) {
339                 if (*argcp > 1 && !strcmp((*argv)[1], "-h"))
340                         fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
341                                    alias_command, alias_string);
342                 if (alias_string[0] == '!') {
343                         struct child_process child = CHILD_PROCESS_INIT;
344                         int nongit_ok;
345
346                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
347                         setup_git_directory_gently(&nongit_ok);
348
349                         commit_pager_choice();
350
351                         child.use_shell = 1;
352                         child.clean_on_exit = 1;
353                         child.wait_after_clean = 1;
354                         child.trace2_child_class = "shell_alias";
355                         strvec_push(&child.args, alias_string + 1);
356                         strvec_pushv(&child.args, (*argv) + 1);
357
358                         trace2_cmd_alias(alias_command, child.args.v);
359                         trace2_cmd_list_config();
360                         trace2_cmd_list_env_vars();
361                         trace2_cmd_name("_run_shell_alias_");
362
363                         ret = run_command(&child);
364                         if (ret >= 0)   /* normal exit */
365                                 exit(ret);
366
367                         die_errno(_("while expanding alias '%s': '%s'"),
368                                   alias_command, alias_string + 1);
369                 }
370                 count = split_cmdline(alias_string, &new_argv);
371                 if (count < 0)
372                         die(_("bad alias.%s string: %s"), alias_command,
373                             _(split_cmdline_strerror(count)));
374                 option_count = handle_options(&new_argv, &count, &envchanged);
375                 if (envchanged)
376                         die(_("alias '%s' changes environment variables.\n"
377                               "You can use '!git' in the alias to do this"),
378                             alias_command);
379                 MOVE_ARRAY(new_argv - option_count, new_argv, count);
380                 new_argv -= option_count;
381
382                 if (count < 1)
383                         die(_("empty alias for %s"), alias_command);
384
385                 if (!strcmp(alias_command, new_argv[0]))
386                         die(_("recursive alias: %s"), alias_command);
387
388                 trace_argv_printf(new_argv,
389                                   "trace: alias expansion: %s =>",
390                                   alias_command);
391
392                 REALLOC_ARRAY(new_argv, count + *argcp);
393                 /* insert after command name */
394                 COPY_ARRAY(new_argv + count, *argv + 1, *argcp);
395
396                 trace2_cmd_alias(alias_command, new_argv);
397                 trace2_cmd_list_config();
398                 trace2_cmd_list_env_vars();
399
400                 *argv = new_argv;
401                 *argcp += count - 1;
402
403                 ret = 1;
404         }
405
406         errno = saved_errno;
407
408         return ret;
409 }
410
411 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
412 {
413         int status, help;
414         struct stat st;
415         const char *prefix;
416
417         prefix = NULL;
418         help = argc == 2 && !strcmp(argv[1], "-h");
419         if (!help) {
420                 if (p->option & RUN_SETUP)
421                         prefix = setup_git_directory();
422                 else if (p->option & RUN_SETUP_GENTLY) {
423                         int nongit_ok;
424                         prefix = setup_git_directory_gently(&nongit_ok);
425                 }
426                 prefix = precompose_argv_prefix(argc, argv, prefix);
427                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
428                     !(p->option & DELAY_PAGER_CONFIG))
429                         use_pager = check_pager_config(p->cmd);
430                 if (use_pager == -1 && p->option & USE_PAGER)
431                         use_pager = 1;
432
433                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
434                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
435                         trace_repo_setup(prefix);
436         }
437         commit_pager_choice();
438
439         if (!help && get_super_prefix()) {
440                 if (!(p->option & SUPPORT_SUPER_PREFIX))
441                         die(_("%s doesn't support --super-prefix"), p->cmd);
442         }
443
444         if (!help && p->option & NEED_WORK_TREE)
445                 setup_work_tree();
446
447         trace_argv_printf(argv, "trace: built-in: git");
448         trace2_cmd_name(p->cmd);
449         trace2_cmd_list_config();
450         trace2_cmd_list_env_vars();
451
452         validate_cache_entries(the_repository->index);
453         status = p->fn(argc, argv, prefix);
454         validate_cache_entries(the_repository->index);
455
456         if (status)
457                 return status;
458
459         /* Somebody closed stdout? */
460         if (fstat(fileno(stdout), &st))
461                 return 0;
462         /* Ignore write errors for pipes and sockets.. */
463         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
464                 return 0;
465
466         /* Check for ENOSPC and EIO errors.. */
467         if (fflush(stdout))
468                 die_errno(_("write failure on standard output"));
469         if (ferror(stdout))
470                 die(_("unknown write failure on standard output"));
471         if (fclose(stdout))
472                 die_errno(_("close failed on standard output"));
473         return 0;
474 }
475
476 static struct cmd_struct commands[] = {
477         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
478         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
479         { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
480         { "apply", cmd_apply, RUN_SETUP_GENTLY },
481         { "archive", cmd_archive, RUN_SETUP_GENTLY },
482         { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
483         { "blame", cmd_blame, RUN_SETUP },
484         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
485         { "bugreport", cmd_bugreport, RUN_SETUP_GENTLY },
486         { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
487         { "cat-file", cmd_cat_file, RUN_SETUP },
488         { "check-attr", cmd_check_attr, RUN_SETUP },
489         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
490         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
491         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
492         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
493         { "checkout-index", cmd_checkout_index,
494                 RUN_SETUP | NEED_WORK_TREE},
495         { "cherry", cmd_cherry, RUN_SETUP },
496         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
497         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
498         { "clone", cmd_clone },
499         { "column", cmd_column, RUN_SETUP_GENTLY },
500         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
501         { "commit-graph", cmd_commit_graph, RUN_SETUP },
502         { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
503         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
504         { "count-objects", cmd_count_objects, RUN_SETUP },
505         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
506         { "credential-cache", cmd_credential_cache },
507         { "credential-cache--daemon", cmd_credential_cache_daemon },
508         { "credential-store", cmd_credential_store },
509         { "describe", cmd_describe, RUN_SETUP },
510         { "diff", cmd_diff, NO_PARSEOPT },
511         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
512         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
513         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
514         { "difftool", cmd_difftool, RUN_SETUP_GENTLY },
515         { "env--helper", cmd_env__helper },
516         { "fast-export", cmd_fast_export, RUN_SETUP },
517         { "fast-import", cmd_fast_import, RUN_SETUP | NO_PARSEOPT },
518         { "fetch", cmd_fetch, RUN_SETUP },
519         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
520         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
521         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
522         { "for-each-repo", cmd_for_each_repo, RUN_SETUP_GENTLY },
523         { "format-patch", cmd_format_patch, RUN_SETUP },
524         { "fsck", cmd_fsck, RUN_SETUP },
525         { "fsck-objects", cmd_fsck, RUN_SETUP },
526         { "gc", cmd_gc, RUN_SETUP },
527         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
528         { "grep", cmd_grep, RUN_SETUP_GENTLY },
529         { "hash-object", cmd_hash_object },
530         { "help", cmd_help },
531         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
532         { "init", cmd_init_db },
533         { "init-db", cmd_init_db },
534         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
535         { "log", cmd_log, RUN_SETUP },
536         { "ls-files", cmd_ls_files, RUN_SETUP },
537         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
538         { "ls-tree", cmd_ls_tree, RUN_SETUP },
539         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
540         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
541         { "maintenance", cmd_maintenance, RUN_SETUP | NO_PARSEOPT },
542         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
543         { "merge-base", cmd_merge_base, RUN_SETUP },
544         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
545         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
546         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
547         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
548         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
549         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
550         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
551         { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
552         { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
553         { "mktree", cmd_mktree, RUN_SETUP },
554         { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP_GENTLY },
555         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
556         { "name-rev", cmd_name_rev, RUN_SETUP },
557         { "notes", cmd_notes, RUN_SETUP },
558         { "pack-objects", cmd_pack_objects, RUN_SETUP },
559         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
560         { "pack-refs", cmd_pack_refs, RUN_SETUP },
561         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
562         { "pickaxe", cmd_blame, RUN_SETUP },
563         { "prune", cmd_prune, RUN_SETUP },
564         { "prune-packed", cmd_prune_packed, RUN_SETUP },
565         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
566         { "push", cmd_push, RUN_SETUP },
567         { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },
568         { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
569         { "rebase", cmd_rebase, RUN_SETUP | NEED_WORK_TREE },
570         { "rebase--interactive", cmd_rebase__interactive, RUN_SETUP | NEED_WORK_TREE },
571         { "receive-pack", cmd_receive_pack },
572         { "reflog", cmd_reflog, RUN_SETUP },
573         { "remote", cmd_remote, RUN_SETUP },
574         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
575         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
576         { "repack", cmd_repack, RUN_SETUP },
577         { "replace", cmd_replace, RUN_SETUP },
578         { "rerere", cmd_rerere, RUN_SETUP },
579         { "reset", cmd_reset, RUN_SETUP },
580         { "restore", cmd_restore, RUN_SETUP | NEED_WORK_TREE },
581         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
582         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
583         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
584         { "rm", cmd_rm, RUN_SETUP },
585         { "send-pack", cmd_send_pack, RUN_SETUP },
586         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
587         { "show", cmd_show, RUN_SETUP },
588         { "show-branch", cmd_show_branch, RUN_SETUP },
589         { "show-index", cmd_show_index, RUN_SETUP_GENTLY },
590         { "show-ref", cmd_show_ref, RUN_SETUP },
591         { "sparse-checkout", cmd_sparse_checkout, RUN_SETUP | NEED_WORK_TREE },
592         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
593         { "stash", cmd_stash, RUN_SETUP | NEED_WORK_TREE },
594         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
595         { "stripspace", cmd_stripspace },
596         { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
597         { "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },
598         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
599         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
600         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
601         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
602         { "update-index", cmd_update_index, RUN_SETUP },
603         { "update-ref", cmd_update_ref, RUN_SETUP },
604         { "update-server-info", cmd_update_server_info, RUN_SETUP },
605         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
606         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
607         { "upload-pack", cmd_upload_pack },
608         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
609         { "verify-commit", cmd_verify_commit, RUN_SETUP },
610         { "verify-pack", cmd_verify_pack },
611         { "verify-tag", cmd_verify_tag, RUN_SETUP },
612         { "version", cmd_version },
613         { "whatchanged", cmd_whatchanged, RUN_SETUP },
614         { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
615         { "write-tree", cmd_write_tree, RUN_SETUP },
616 };
617
618 static struct cmd_struct *get_builtin(const char *s)
619 {
620         int i;
621         for (i = 0; i < ARRAY_SIZE(commands); i++) {
622                 struct cmd_struct *p = commands + i;
623                 if (!strcmp(s, p->cmd))
624                         return p;
625         }
626         return NULL;
627 }
628
629 int is_builtin(const char *s)
630 {
631         return !!get_builtin(s);
632 }
633
634 static void list_builtins(struct string_list *out, unsigned int exclude_option)
635 {
636         int i;
637         for (i = 0; i < ARRAY_SIZE(commands); i++) {
638                 if (exclude_option &&
639                     (commands[i].option & exclude_option))
640                         continue;
641                 string_list_append(out, commands[i].cmd);
642         }
643 }
644
645 void load_builtin_commands(const char *prefix, struct cmdnames *cmds)
646 {
647         const char *name;
648         int i;
649
650         /*
651          * Callers can ask for a subset of the commands based on a certain
652          * prefix, which is then dropped from the added names. The names in
653          * the `commands[]` array do not have the `git-` prefix, though,
654          * therefore we must expect the `prefix` to at least start with `git-`.
655          */
656         if (!skip_prefix(prefix, "git-", &prefix))
657                 BUG("prefix '%s' must start with 'git-'", prefix);
658
659         for (i = 0; i < ARRAY_SIZE(commands); i++)
660                 if (skip_prefix(commands[i].cmd, prefix, &name))
661                         add_cmdname(cmds, name, strlen(name));
662 }
663
664 #ifdef STRIP_EXTENSION
665 static void strip_extension(const char **argv)
666 {
667         size_t len;
668
669         if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
670                 argv[0] = xmemdupz(argv[0], len);
671 }
672 #else
673 #define strip_extension(cmd)
674 #endif
675
676 static void handle_builtin(int argc, const char **argv)
677 {
678         struct strvec args = STRVEC_INIT;
679         const char *cmd;
680         struct cmd_struct *builtin;
681
682         strip_extension(argv);
683         cmd = argv[0];
684
685         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
686         if (argc > 1 && !strcmp(argv[1], "--help")) {
687                 int i;
688
689                 argv[1] = argv[0];
690                 argv[0] = cmd = "help";
691
692                 for (i = 0; i < argc; i++) {
693                         strvec_push(&args, argv[i]);
694                         if (!i)
695                                 strvec_push(&args, "--exclude-guides");
696                 }
697
698                 argc++;
699                 argv = args.v;
700         }
701
702         builtin = get_builtin(cmd);
703         if (builtin)
704                 exit(run_builtin(builtin, argc, argv));
705         strvec_clear(&args);
706 }
707
708 static void execv_dashed_external(const char **argv)
709 {
710         struct child_process cmd = CHILD_PROCESS_INIT;
711         int status;
712
713         if (get_super_prefix())
714                 die(_("%s doesn't support --super-prefix"), argv[0]);
715
716         if (use_pager == -1 && !is_builtin(argv[0]))
717                 use_pager = check_pager_config(argv[0]);
718         commit_pager_choice();
719
720         strvec_pushf(&cmd.args, "git-%s", argv[0]);
721         strvec_pushv(&cmd.args, argv + 1);
722         cmd.clean_on_exit = 1;
723         cmd.wait_after_clean = 1;
724         cmd.silent_exec_failure = 1;
725         cmd.trace2_child_class = "dashed";
726
727         trace2_cmd_name("_run_dashed_");
728
729         /*
730          * The code in run_command() logs trace2 child_start/child_exit
731          * events, so we do not need to report exec/exec_result events here.
732          */
733         trace_argv_printf(cmd.args.v, "trace: exec:");
734
735         /*
736          * If we fail because the command is not found, it is
737          * OK to return. Otherwise, we just pass along the status code,
738          * or our usual generic code if we were not even able to exec
739          * the program.
740          */
741         status = run_command(&cmd);
742
743         /*
744          * If the child process ran and we are now going to exit, emit a
745          * generic string as our trace2 command verb to indicate that we
746          * launched a dashed command.
747          */
748         if (status >= 0)
749                 exit(status);
750         else if (errno != ENOENT)
751                 exit(128);
752 }
753
754 static int run_argv(int *argcp, const char ***argv)
755 {
756         int done_alias = 0;
757         struct string_list cmd_list = STRING_LIST_INIT_NODUP;
758         struct string_list_item *seen;
759
760         while (1) {
761                 /*
762                  * If we tried alias and futzed with our environment,
763                  * it no longer is safe to invoke builtins directly in
764                  * general.  We have to spawn them as dashed externals.
765                  *
766                  * NEEDSWORK: if we can figure out cases
767                  * where it is safe to do, we can avoid spawning a new
768                  * process.
769                  */
770                 if (!done_alias)
771                         handle_builtin(*argcp, *argv);
772                 else if (get_builtin(**argv)) {
773                         struct strvec args = STRVEC_INIT;
774                         int i;
775
776                         /*
777                          * The current process is committed to launching a
778                          * child process to run the command named in (**argv)
779                          * and exiting.  Log a generic string as the trace2
780                          * command verb to indicate this.  Note that the child
781                          * process will log the actual verb when it runs.
782                          */
783                         trace2_cmd_name("_run_git_alias_");
784
785                         if (get_super_prefix())
786                                 die("%s doesn't support --super-prefix", **argv);
787
788                         commit_pager_choice();
789
790                         strvec_push(&args, "git");
791                         for (i = 0; i < *argcp; i++)
792                                 strvec_push(&args, (*argv)[i]);
793
794                         trace_argv_printf(args.v, "trace: exec:");
795
796                         /*
797                          * if we fail because the command is not found, it is
798                          * OK to return. Otherwise, we just pass along the status code.
799                          */
800                         i = run_command_v_opt_tr2(args.v, RUN_SILENT_EXEC_FAILURE |
801                                                   RUN_CLEAN_ON_EXIT | RUN_WAIT_AFTER_CLEAN, "git_alias");
802                         if (i >= 0 || errno != ENOENT)
803                                 exit(i);
804                         die("could not execute builtin %s", **argv);
805                 }
806
807                 /* .. then try the external ones */
808                 execv_dashed_external(*argv);
809
810                 seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);
811                 if (seen) {
812                         int i;
813                         struct strbuf sb = STRBUF_INIT;
814                         for (i = 0; i < cmd_list.nr; i++) {
815                                 struct string_list_item *item = &cmd_list.items[i];
816
817                                 strbuf_addf(&sb, "\n  %s", item->string);
818                                 if (item == seen)
819                                         strbuf_addstr(&sb, " <==");
820                                 else if (i == cmd_list.nr - 1)
821                                         strbuf_addstr(&sb, " ==>");
822                         }
823                         die(_("alias loop detected: expansion of '%s' does"
824                               " not terminate:%s"), cmd_list.items[0].string, sb.buf);
825                 }
826
827                 string_list_append(&cmd_list, *argv[0]);
828
829                 /*
830                  * It could be an alias -- this works around the insanity
831                  * of overriding "git log" with "git show" by having
832                  * alias.log = show
833                  */
834                 if (!handle_alias(argcp, argv))
835                         break;
836                 done_alias = 1;
837         }
838
839         string_list_clear(&cmd_list, 0);
840
841         return done_alias;
842 }
843
844 int cmd_main(int argc, const char **argv)
845 {
846         const char *cmd;
847         int done_help = 0;
848
849         cmd = argv[0];
850         if (!cmd)
851                 cmd = "git-help";
852         else {
853                 const char *slash = find_last_dir_sep(cmd);
854                 if (slash)
855                         cmd = slash + 1;
856         }
857
858         trace_command_performance(argv);
859
860         /*
861          * "git-xxxx" is the same as "git xxxx", but we obviously:
862          *
863          *  - cannot take flags in between the "git" and the "xxxx".
864          *  - cannot execute it externally (since it would just do
865          *    the same thing over again)
866          *
867          * So we just directly call the builtin handler, and die if
868          * that one cannot handle it.
869          */
870         if (skip_prefix(cmd, "git-", &cmd)) {
871                 argv[0] = cmd;
872                 handle_builtin(argc, argv);
873                 die(_("cannot handle %s as a builtin"), cmd);
874         }
875
876         /* Look for flags.. */
877         argv++;
878         argc--;
879         handle_options(&argv, &argc, NULL);
880         if (argc > 0) {
881                 /* translate --help and --version into commands */
882                 skip_prefix(argv[0], "--", &argv[0]);
883         } else {
884                 /* The user didn't specify a command; give them help */
885                 commit_pager_choice();
886                 printf(_("usage: %s\n\n"), git_usage_string);
887                 list_common_cmds_help();
888                 printf("\n%s\n", _(git_more_info_string));
889                 exit(1);
890         }
891         cmd = argv[0];
892
893         /*
894          * We use PATH to find git commands, but we prepend some higher
895          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
896          * environment, and the $(gitexecdir) from the Makefile at build
897          * time.
898          */
899         setup_path();
900
901         while (1) {
902                 int was_alias = run_argv(&argc, &argv);
903                 if (errno != ENOENT)
904                         break;
905                 if (was_alias) {
906                         fprintf(stderr, _("expansion of alias '%s' failed; "
907                                           "'%s' is not a git command\n"),
908                                 cmd, argv[0]);
909                         exit(1);
910                 }
911                 if (!done_help) {
912                         cmd = argv[0] = help_unknown_cmd(cmd);
913                         done_help = 1;
914                 } else
915                         break;
916         }
917
918         fprintf(stderr, _("failed to run command '%s': %s\n"),
919                 cmd, strerror(errno));
920
921         return 1;
922 }