Merge branch 'js/merge-already-up-to-date-message-reword'
[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 (!strcmp(cmd, "--config-env")) {
259                         if (*argc < 2) {
260                                 fprintf(stderr, _("no config key given for --config-env\n" ));
261                                 usage(git_usage_string);
262                         }
263                         git_config_push_env((*argv)[1]);
264                         (*argv)++;
265                         (*argc)--;
266                 } else if (skip_prefix(cmd, "--config-env=", &cmd)) {
267                         git_config_push_env(cmd);
268                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
269                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
270                         if (envchanged)
271                                 *envchanged = 1;
272                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
273                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
274                         if (envchanged)
275                                 *envchanged = 1;
276                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
277                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
278                         if (envchanged)
279                                 *envchanged = 1;
280                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
281                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
282                         if (envchanged)
283                                 *envchanged = 1;
284                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
285                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
286                         if (envchanged)
287                                 *envchanged = 1;
288                 } else if (!strcmp(cmd, "--no-optional-locks")) {
289                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
290                         if (envchanged)
291                                 *envchanged = 1;
292                 } else if (!strcmp(cmd, "--shallow-file")) {
293                         (*argv)++;
294                         (*argc)--;
295                         set_alternate_shallow_file(the_repository, (*argv)[0], 1);
296                         if (envchanged)
297                                 *envchanged = 1;
298                 } else if (!strcmp(cmd, "-C")) {
299                         if (*argc < 2) {
300                                 fprintf(stderr, _("no directory given for -C\n" ));
301                                 usage(git_usage_string);
302                         }
303                         if ((*argv)[1][0]) {
304                                 if (chdir((*argv)[1]))
305                                         die_errno("cannot change to '%s'", (*argv)[1]);
306                                 if (envchanged)
307                                         *envchanged = 1;
308                         }
309                         (*argv)++;
310                         (*argc)--;
311                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
312                         trace2_cmd_name("_query_");
313                         if (!strcmp(cmd, "parseopt")) {
314                                 struct string_list list = STRING_LIST_INIT_DUP;
315                                 int i;
316
317                                 list_builtins(&list, NO_PARSEOPT);
318                                 for (i = 0; i < list.nr; i++)
319                                         printf("%s ", list.items[i].string);
320                                 string_list_clear(&list, 0);
321                                 exit(0);
322                         } else {
323                                 exit(list_cmds(cmd));
324                         }
325                 } else {
326                         fprintf(stderr, _("unknown option: %s\n"), cmd);
327                         usage(git_usage_string);
328                 }
329
330                 (*argv)++;
331                 (*argc)--;
332         }
333         return (*argv) - orig_argv;
334 }
335
336 static int handle_alias(int *argcp, const char ***argv)
337 {
338         int envchanged = 0, ret = 0, saved_errno = errno;
339         int count, option_count;
340         const char **new_argv;
341         const char *alias_command;
342         char *alias_string;
343
344         alias_command = (*argv)[0];
345         alias_string = alias_lookup(alias_command);
346         if (alias_string) {
347                 if (*argcp > 1 && !strcmp((*argv)[1], "-h"))
348                         fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
349                                    alias_command, alias_string);
350                 if (alias_string[0] == '!') {
351                         struct child_process child = CHILD_PROCESS_INIT;
352                         int nongit_ok;
353
354                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
355                         setup_git_directory_gently(&nongit_ok);
356
357                         commit_pager_choice();
358
359                         child.use_shell = 1;
360                         child.clean_on_exit = 1;
361                         child.wait_after_clean = 1;
362                         child.trace2_child_class = "shell_alias";
363                         strvec_push(&child.args, alias_string + 1);
364                         strvec_pushv(&child.args, (*argv) + 1);
365
366                         trace2_cmd_alias(alias_command, child.args.v);
367                         trace2_cmd_list_config();
368                         trace2_cmd_list_env_vars();
369                         trace2_cmd_name("_run_shell_alias_");
370
371                         ret = run_command(&child);
372                         if (ret >= 0)   /* normal exit */
373                                 exit(ret);
374
375                         die_errno(_("while expanding alias '%s': '%s'"),
376                                   alias_command, alias_string + 1);
377                 }
378                 count = split_cmdline(alias_string, &new_argv);
379                 if (count < 0)
380                         die(_("bad alias.%s string: %s"), alias_command,
381                             _(split_cmdline_strerror(count)));
382                 option_count = handle_options(&new_argv, &count, &envchanged);
383                 if (envchanged)
384                         die(_("alias '%s' changes environment variables.\n"
385                               "You can use '!git' in the alias to do this"),
386                             alias_command);
387                 MOVE_ARRAY(new_argv - option_count, new_argv, count);
388                 new_argv -= option_count;
389
390                 if (count < 1)
391                         die(_("empty alias for %s"), alias_command);
392
393                 if (!strcmp(alias_command, new_argv[0]))
394                         die(_("recursive alias: %s"), alias_command);
395
396                 trace_argv_printf(new_argv,
397                                   "trace: alias expansion: %s =>",
398                                   alias_command);
399
400                 REALLOC_ARRAY(new_argv, count + *argcp);
401                 /* insert after command name */
402                 COPY_ARRAY(new_argv + count, *argv + 1, *argcp);
403
404                 trace2_cmd_alias(alias_command, new_argv);
405                 trace2_cmd_list_config();
406                 trace2_cmd_list_env_vars();
407
408                 *argv = new_argv;
409                 *argcp += count - 1;
410
411                 ret = 1;
412         }
413
414         errno = saved_errno;
415
416         return ret;
417 }
418
419 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
420 {
421         int status, help;
422         struct stat st;
423         const char *prefix;
424
425         prefix = NULL;
426         help = argc == 2 && !strcmp(argv[1], "-h");
427         if (!help) {
428                 if (p->option & RUN_SETUP)
429                         prefix = setup_git_directory();
430                 else if (p->option & RUN_SETUP_GENTLY) {
431                         int nongit_ok;
432                         prefix = setup_git_directory_gently(&nongit_ok);
433                 }
434                 precompose_argv_prefix(argc, argv, NULL);
435                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
436                     !(p->option & DELAY_PAGER_CONFIG))
437                         use_pager = check_pager_config(p->cmd);
438                 if (use_pager == -1 && p->option & USE_PAGER)
439                         use_pager = 1;
440
441                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
442                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
443                         trace_repo_setup(prefix);
444         }
445         commit_pager_choice();
446
447         if (!help && get_super_prefix()) {
448                 if (!(p->option & SUPPORT_SUPER_PREFIX))
449                         die(_("%s doesn't support --super-prefix"), p->cmd);
450         }
451
452         if (!help && p->option & NEED_WORK_TREE)
453                 setup_work_tree();
454
455         trace_argv_printf(argv, "trace: built-in: git");
456         trace2_cmd_name(p->cmd);
457         trace2_cmd_list_config();
458         trace2_cmd_list_env_vars();
459
460         validate_cache_entries(the_repository->index);
461         status = p->fn(argc, argv, prefix);
462         validate_cache_entries(the_repository->index);
463
464         if (status)
465                 return status;
466
467         /* Somebody closed stdout? */
468         if (fstat(fileno(stdout), &st))
469                 return 0;
470         /* Ignore write errors for pipes and sockets.. */
471         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
472                 return 0;
473
474         /* Check for ENOSPC and EIO errors.. */
475         if (fflush(stdout))
476                 die_errno(_("write failure on standard output"));
477         if (ferror(stdout))
478                 die(_("unknown write failure on standard output"));
479         if (fclose(stdout))
480                 die_errno(_("close failed on standard output"));
481         return 0;
482 }
483
484 static struct cmd_struct commands[] = {
485         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
486         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
487         { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
488         { "apply", cmd_apply, RUN_SETUP_GENTLY },
489         { "archive", cmd_archive, RUN_SETUP_GENTLY },
490         { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
491         { "blame", cmd_blame, RUN_SETUP },
492         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
493         { "bugreport", cmd_bugreport, RUN_SETUP_GENTLY },
494         { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
495         { "cat-file", cmd_cat_file, RUN_SETUP },
496         { "check-attr", cmd_check_attr, RUN_SETUP },
497         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
498         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
499         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
500         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
501         { "checkout--worker", cmd_checkout__worker,
502                 RUN_SETUP | NEED_WORK_TREE | SUPPORT_SUPER_PREFIX },
503         { "checkout-index", cmd_checkout_index,
504                 RUN_SETUP | NEED_WORK_TREE},
505         { "cherry", cmd_cherry, RUN_SETUP },
506         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
507         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
508         { "clone", cmd_clone },
509         { "column", cmd_column, RUN_SETUP_GENTLY },
510         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
511         { "commit-graph", cmd_commit_graph, RUN_SETUP },
512         { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
513         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
514         { "count-objects", cmd_count_objects, RUN_SETUP },
515         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
516         { "credential-cache", cmd_credential_cache },
517         { "credential-cache--daemon", cmd_credential_cache_daemon },
518         { "credential-store", cmd_credential_store },
519         { "describe", cmd_describe, RUN_SETUP },
520         { "diff", cmd_diff, NO_PARSEOPT },
521         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
522         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
523         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
524         { "difftool", cmd_difftool, RUN_SETUP_GENTLY },
525         { "env--helper", cmd_env__helper },
526         { "fast-export", cmd_fast_export, RUN_SETUP },
527         { "fast-import", cmd_fast_import, RUN_SETUP | NO_PARSEOPT },
528         { "fetch", cmd_fetch, RUN_SETUP },
529         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
530         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
531         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
532         { "for-each-repo", cmd_for_each_repo, RUN_SETUP_GENTLY },
533         { "format-patch", cmd_format_patch, RUN_SETUP },
534         { "fsck", cmd_fsck, RUN_SETUP },
535         { "fsck-objects", cmd_fsck, RUN_SETUP },
536         { "gc", cmd_gc, RUN_SETUP },
537         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
538         { "grep", cmd_grep, RUN_SETUP_GENTLY },
539         { "hash-object", cmd_hash_object },
540         { "help", cmd_help },
541         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
542         { "init", cmd_init_db },
543         { "init-db", cmd_init_db },
544         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
545         { "log", cmd_log, RUN_SETUP },
546         { "ls-files", cmd_ls_files, RUN_SETUP },
547         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
548         { "ls-tree", cmd_ls_tree, RUN_SETUP },
549         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
550         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
551         { "maintenance", cmd_maintenance, RUN_SETUP | NO_PARSEOPT },
552         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
553         { "merge-base", cmd_merge_base, RUN_SETUP },
554         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
555         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
556         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
557         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
558         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
559         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
560         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
561         { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
562         { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
563         { "mktree", cmd_mktree, RUN_SETUP },
564         { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP_GENTLY },
565         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
566         { "name-rev", cmd_name_rev, RUN_SETUP },
567         { "notes", cmd_notes, RUN_SETUP },
568         { "pack-objects", cmd_pack_objects, RUN_SETUP },
569         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
570         { "pack-refs", cmd_pack_refs, RUN_SETUP },
571         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
572         { "pickaxe", cmd_blame, RUN_SETUP },
573         { "prune", cmd_prune, RUN_SETUP },
574         { "prune-packed", cmd_prune_packed, RUN_SETUP },
575         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
576         { "push", cmd_push, RUN_SETUP },
577         { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },
578         { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
579         { "rebase", cmd_rebase, RUN_SETUP | NEED_WORK_TREE },
580         { "rebase--interactive", cmd_rebase__interactive, RUN_SETUP | NEED_WORK_TREE },
581         { "receive-pack", cmd_receive_pack },
582         { "reflog", cmd_reflog, RUN_SETUP },
583         { "remote", cmd_remote, RUN_SETUP },
584         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
585         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
586         { "repack", cmd_repack, RUN_SETUP },
587         { "replace", cmd_replace, RUN_SETUP },
588         { "rerere", cmd_rerere, RUN_SETUP },
589         { "reset", cmd_reset, RUN_SETUP },
590         { "restore", cmd_restore, RUN_SETUP | NEED_WORK_TREE },
591         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
592         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
593         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
594         { "rm", cmd_rm, RUN_SETUP },
595         { "send-pack", cmd_send_pack, RUN_SETUP },
596         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
597         { "show", cmd_show, RUN_SETUP },
598         { "show-branch", cmd_show_branch, RUN_SETUP },
599         { "show-index", cmd_show_index, RUN_SETUP_GENTLY },
600         { "show-ref", cmd_show_ref, RUN_SETUP },
601         { "sparse-checkout", cmd_sparse_checkout, RUN_SETUP | NEED_WORK_TREE },
602         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
603         { "stash", cmd_stash, RUN_SETUP | NEED_WORK_TREE },
604         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
605         { "stripspace", cmd_stripspace },
606         { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
607         { "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },
608         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
609         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
610         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
611         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
612         { "update-index", cmd_update_index, RUN_SETUP },
613         { "update-ref", cmd_update_ref, RUN_SETUP },
614         { "update-server-info", cmd_update_server_info, RUN_SETUP },
615         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
616         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
617         { "upload-pack", cmd_upload_pack },
618         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
619         { "verify-commit", cmd_verify_commit, RUN_SETUP },
620         { "verify-pack", cmd_verify_pack },
621         { "verify-tag", cmd_verify_tag, RUN_SETUP },
622         { "version", cmd_version },
623         { "whatchanged", cmd_whatchanged, RUN_SETUP },
624         { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
625         { "write-tree", cmd_write_tree, RUN_SETUP },
626 };
627
628 static struct cmd_struct *get_builtin(const char *s)
629 {
630         int i;
631         for (i = 0; i < ARRAY_SIZE(commands); i++) {
632                 struct cmd_struct *p = commands + i;
633                 if (!strcmp(s, p->cmd))
634                         return p;
635         }
636         return NULL;
637 }
638
639 int is_builtin(const char *s)
640 {
641         return !!get_builtin(s);
642 }
643
644 static void list_builtins(struct string_list *out, unsigned int exclude_option)
645 {
646         int i;
647         for (i = 0; i < ARRAY_SIZE(commands); i++) {
648                 if (exclude_option &&
649                     (commands[i].option & exclude_option))
650                         continue;
651                 string_list_append(out, commands[i].cmd);
652         }
653 }
654
655 void load_builtin_commands(const char *prefix, struct cmdnames *cmds)
656 {
657         const char *name;
658         int i;
659
660         /*
661          * Callers can ask for a subset of the commands based on a certain
662          * prefix, which is then dropped from the added names. The names in
663          * the `commands[]` array do not have the `git-` prefix, though,
664          * therefore we must expect the `prefix` to at least start with `git-`.
665          */
666         if (!skip_prefix(prefix, "git-", &prefix))
667                 BUG("prefix '%s' must start with 'git-'", prefix);
668
669         for (i = 0; i < ARRAY_SIZE(commands); i++)
670                 if (skip_prefix(commands[i].cmd, prefix, &name))
671                         add_cmdname(cmds, name, strlen(name));
672 }
673
674 #ifdef STRIP_EXTENSION
675 static void strip_extension(const char **argv)
676 {
677         size_t len;
678
679         if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
680                 argv[0] = xmemdupz(argv[0], len);
681 }
682 #else
683 #define strip_extension(cmd)
684 #endif
685
686 static void handle_builtin(int argc, const char **argv)
687 {
688         struct strvec args = STRVEC_INIT;
689         const char *cmd;
690         struct cmd_struct *builtin;
691
692         strip_extension(argv);
693         cmd = argv[0];
694
695         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
696         if (argc > 1 && !strcmp(argv[1], "--help")) {
697                 int i;
698
699                 argv[1] = argv[0];
700                 argv[0] = cmd = "help";
701
702                 for (i = 0; i < argc; i++) {
703                         strvec_push(&args, argv[i]);
704                         if (!i)
705                                 strvec_push(&args, "--exclude-guides");
706                 }
707
708                 argc++;
709                 argv = args.v;
710         }
711
712         builtin = get_builtin(cmd);
713         if (builtin)
714                 exit(run_builtin(builtin, argc, argv));
715         strvec_clear(&args);
716 }
717
718 static void execv_dashed_external(const char **argv)
719 {
720         struct child_process cmd = CHILD_PROCESS_INIT;
721         int status;
722
723         if (get_super_prefix())
724                 die(_("%s doesn't support --super-prefix"), argv[0]);
725
726         if (use_pager == -1 && !is_builtin(argv[0]))
727                 use_pager = check_pager_config(argv[0]);
728         commit_pager_choice();
729
730         strvec_pushf(&cmd.args, "git-%s", argv[0]);
731         strvec_pushv(&cmd.args, argv + 1);
732         cmd.clean_on_exit = 1;
733         cmd.wait_after_clean = 1;
734         cmd.silent_exec_failure = 1;
735         cmd.trace2_child_class = "dashed";
736
737         trace2_cmd_name("_run_dashed_");
738
739         /*
740          * The code in run_command() logs trace2 child_start/child_exit
741          * events, so we do not need to report exec/exec_result events here.
742          */
743         trace_argv_printf(cmd.args.v, "trace: exec:");
744
745         /*
746          * If we fail because the command is not found, it is
747          * OK to return. Otherwise, we just pass along the status code,
748          * or our usual generic code if we were not even able to exec
749          * the program.
750          */
751         status = run_command(&cmd);
752
753         /*
754          * If the child process ran and we are now going to exit, emit a
755          * generic string as our trace2 command verb to indicate that we
756          * launched a dashed command.
757          */
758         if (status >= 0)
759                 exit(status);
760         else if (errno != ENOENT)
761                 exit(128);
762 }
763
764 static int run_argv(int *argcp, const char ***argv)
765 {
766         int done_alias = 0;
767         struct string_list cmd_list = STRING_LIST_INIT_NODUP;
768         struct string_list_item *seen;
769
770         while (1) {
771                 /*
772                  * If we tried alias and futzed with our environment,
773                  * it no longer is safe to invoke builtins directly in
774                  * general.  We have to spawn them as dashed externals.
775                  *
776                  * NEEDSWORK: if we can figure out cases
777                  * where it is safe to do, we can avoid spawning a new
778                  * process.
779                  */
780                 if (!done_alias)
781                         handle_builtin(*argcp, *argv);
782                 else if (get_builtin(**argv)) {
783                         struct strvec args = STRVEC_INIT;
784                         int i;
785
786                         /*
787                          * The current process is committed to launching a
788                          * child process to run the command named in (**argv)
789                          * and exiting.  Log a generic string as the trace2
790                          * command verb to indicate this.  Note that the child
791                          * process will log the actual verb when it runs.
792                          */
793                         trace2_cmd_name("_run_git_alias_");
794
795                         if (get_super_prefix())
796                                 die("%s doesn't support --super-prefix", **argv);
797
798                         commit_pager_choice();
799
800                         strvec_push(&args, "git");
801                         for (i = 0; i < *argcp; i++)
802                                 strvec_push(&args, (*argv)[i]);
803
804                         trace_argv_printf(args.v, "trace: exec:");
805
806                         /*
807                          * if we fail because the command is not found, it is
808                          * OK to return. Otherwise, we just pass along the status code.
809                          */
810                         i = run_command_v_opt_tr2(args.v, RUN_SILENT_EXEC_FAILURE |
811                                                   RUN_CLEAN_ON_EXIT | RUN_WAIT_AFTER_CLEAN, "git_alias");
812                         if (i >= 0 || errno != ENOENT)
813                                 exit(i);
814                         die("could not execute builtin %s", **argv);
815                 }
816
817                 /* .. then try the external ones */
818                 execv_dashed_external(*argv);
819
820                 seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);
821                 if (seen) {
822                         int i;
823                         struct strbuf sb = STRBUF_INIT;
824                         for (i = 0; i < cmd_list.nr; i++) {
825                                 struct string_list_item *item = &cmd_list.items[i];
826
827                                 strbuf_addf(&sb, "\n  %s", item->string);
828                                 if (item == seen)
829                                         strbuf_addstr(&sb, " <==");
830                                 else if (i == cmd_list.nr - 1)
831                                         strbuf_addstr(&sb, " ==>");
832                         }
833                         die(_("alias loop detected: expansion of '%s' does"
834                               " not terminate:%s"), cmd_list.items[0].string, sb.buf);
835                 }
836
837                 string_list_append(&cmd_list, *argv[0]);
838
839                 /*
840                  * It could be an alias -- this works around the insanity
841                  * of overriding "git log" with "git show" by having
842                  * alias.log = show
843                  */
844                 if (!handle_alias(argcp, argv))
845                         break;
846                 done_alias = 1;
847         }
848
849         string_list_clear(&cmd_list, 0);
850
851         return done_alias;
852 }
853
854 int cmd_main(int argc, const char **argv)
855 {
856         const char *cmd;
857         int done_help = 0;
858
859         cmd = argv[0];
860         if (!cmd)
861                 cmd = "git-help";
862         else {
863                 const char *slash = find_last_dir_sep(cmd);
864                 if (slash)
865                         cmd = slash + 1;
866         }
867
868         trace_command_performance(argv);
869
870         /*
871          * "git-xxxx" is the same as "git xxxx", but we obviously:
872          *
873          *  - cannot take flags in between the "git" and the "xxxx".
874          *  - cannot execute it externally (since it would just do
875          *    the same thing over again)
876          *
877          * So we just directly call the builtin handler, and die if
878          * that one cannot handle it.
879          */
880         if (skip_prefix(cmd, "git-", &cmd)) {
881                 argv[0] = cmd;
882                 handle_builtin(argc, argv);
883                 die(_("cannot handle %s as a builtin"), cmd);
884         }
885
886         /* Look for flags.. */
887         argv++;
888         argc--;
889         handle_options(&argv, &argc, NULL);
890         if (argc > 0) {
891                 /* translate --help and --version into commands */
892                 skip_prefix(argv[0], "--", &argv[0]);
893         } else {
894                 /* The user didn't specify a command; give them help */
895                 commit_pager_choice();
896                 printf(_("usage: %s\n\n"), git_usage_string);
897                 list_common_cmds_help();
898                 printf("\n%s\n", _(git_more_info_string));
899                 exit(1);
900         }
901         cmd = argv[0];
902
903         /*
904          * We use PATH to find git commands, but we prepend some higher
905          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
906          * environment, and the $(gitexecdir) from the Makefile at build
907          * time.
908          */
909         setup_path();
910
911         while (1) {
912                 int was_alias = run_argv(&argc, &argv);
913                 if (errno != ENOENT)
914                         break;
915                 if (was_alias) {
916                         fprintf(stderr, _("expansion of alias '%s' failed; "
917                                           "'%s' is not a git command\n"),
918                                 cmd, argv[0]);
919                         exit(1);
920                 }
921                 if (!done_help) {
922                         cmd = argv[0] = help_unknown_cmd(cmd);
923                         done_help = 1;
924                 } else
925                         break;
926         }
927
928         fprintf(stderr, _("failed to run command '%s': %s\n"),
929                 cmd, strerror(errno));
930
931         return 1;
932 }