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