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