Imported Upstream version 2.22.0
[platform/upstream/git.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         int nongit;
66
67         /*
68         * Set up the repository so we can pick up any repo-level config (like
69         * completion.commands).
70         */
71         setup_git_directory_gently(&nongit);
72
73         while (*spec) {
74                 const char *sep = strchrnul(spec, ',');
75                 int len = sep - spec;
76
77                 if (match_token(spec, len, "builtins"))
78                         list_builtins(&list, 0);
79                 else if (match_token(spec, len, "main"))
80                         list_all_main_cmds(&list);
81                 else if (match_token(spec, len, "others"))
82                         list_all_other_cmds(&list);
83                 else if (match_token(spec, len, "nohelpers"))
84                         exclude_helpers_from_list(&list);
85                 else if (match_token(spec, len, "alias"))
86                         list_aliases(&list);
87                 else if (match_token(spec, len, "config"))
88                         list_cmds_by_config(&list);
89                 else if (len > 5 && !strncmp(spec, "list-", 5)) {
90                         struct strbuf sb = STRBUF_INIT;
91
92                         strbuf_add(&sb, spec + 5, len - 5);
93                         list_cmds_by_category(&list, sb.buf);
94                         strbuf_release(&sb);
95                 }
96                 else
97                         die(_("unsupported command listing type '%s'"), spec);
98                 spec += len;
99                 if (*spec == ',')
100                         spec++;
101         }
102         for (i = 0; i < list.nr; i++)
103                 puts(list.items[i].string);
104         string_list_clear(&list, 0);
105         return 0;
106 }
107
108 static void commit_pager_choice(void)
109 {
110         switch (use_pager) {
111         case 0:
112                 setenv("GIT_PAGER", "cat", 1);
113                 break;
114         case 1:
115                 setup_pager();
116                 break;
117         default:
118                 break;
119         }
120 }
121
122 void setup_auto_pager(const char *cmd, int def)
123 {
124         if (use_pager != -1 || pager_in_use())
125                 return;
126         use_pager = check_pager_config(cmd);
127         if (use_pager == -1)
128                 use_pager = def;
129         commit_pager_choice();
130 }
131
132 static int handle_options(const char ***argv, int *argc, int *envchanged)
133 {
134         const char **orig_argv = *argv;
135
136         while (*argc > 0) {
137                 const char *cmd = (*argv)[0];
138                 if (cmd[0] != '-')
139                         break;
140
141                 /*
142                  * For legacy reasons, the "version" and "help"
143                  * commands can be written with "--" prepended
144                  * to make them look like flags.
145                  */
146                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
147                         break;
148
149                 /*
150                  * Check remaining flags.
151                  */
152                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
153                         if (*cmd == '=')
154                                 git_set_exec_path(cmd + 1);
155                         else {
156                                 puts(git_exec_path());
157                                 trace2_cmd_name("_query_");
158                                 exit(0);
159                         }
160                 } else if (!strcmp(cmd, "--html-path")) {
161                         puts(system_path(GIT_HTML_PATH));
162                         trace2_cmd_name("_query_");
163                         exit(0);
164                 } else if (!strcmp(cmd, "--man-path")) {
165                         puts(system_path(GIT_MAN_PATH));
166                         trace2_cmd_name("_query_");
167                         exit(0);
168                 } else if (!strcmp(cmd, "--info-path")) {
169                         puts(system_path(GIT_INFO_PATH));
170                         trace2_cmd_name("_query_");
171                         exit(0);
172                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
173                         use_pager = 1;
174                 } else if (!strcmp(cmd, "-P") || !strcmp(cmd, "--no-pager")) {
175                         use_pager = 0;
176                         if (envchanged)
177                                 *envchanged = 1;
178                 } else if (!strcmp(cmd, "--no-replace-objects")) {
179                         read_replace_refs = 0;
180                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
181                         if (envchanged)
182                                 *envchanged = 1;
183                 } else if (!strcmp(cmd, "--git-dir")) {
184                         if (*argc < 2) {
185                                 fprintf(stderr, _("no directory given for --git-dir\n" ));
186                                 usage(git_usage_string);
187                         }
188                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
189                         if (envchanged)
190                                 *envchanged = 1;
191                         (*argv)++;
192                         (*argc)--;
193                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
194                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
195                         if (envchanged)
196                                 *envchanged = 1;
197                 } else if (!strcmp(cmd, "--namespace")) {
198                         if (*argc < 2) {
199                                 fprintf(stderr, _("no namespace given for --namespace\n" ));
200                                 usage(git_usage_string);
201                         }
202                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
203                         if (envchanged)
204                                 *envchanged = 1;
205                         (*argv)++;
206                         (*argc)--;
207                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
208                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
209                         if (envchanged)
210                                 *envchanged = 1;
211                 } else if (!strcmp(cmd, "--work-tree")) {
212                         if (*argc < 2) {
213                                 fprintf(stderr, _("no directory given for --work-tree\n" ));
214                                 usage(git_usage_string);
215                         }
216                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
217                         if (envchanged)
218                                 *envchanged = 1;
219                         (*argv)++;
220                         (*argc)--;
221                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
222                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
223                         if (envchanged)
224                                 *envchanged = 1;
225                 } else if (!strcmp(cmd, "--super-prefix")) {
226                         if (*argc < 2) {
227                                 fprintf(stderr, _("no prefix given for --super-prefix\n" ));
228                                 usage(git_usage_string);
229                         }
230                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
231                         if (envchanged)
232                                 *envchanged = 1;
233                         (*argv)++;
234                         (*argc)--;
235                 } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
236                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
237                         if (envchanged)
238                                 *envchanged = 1;
239                 } else if (!strcmp(cmd, "--bare")) {
240                         char *cwd = xgetcwd();
241                         is_bare_repository_cfg = 1;
242                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
243                         free(cwd);
244                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
245                         if (envchanged)
246                                 *envchanged = 1;
247                 } else if (!strcmp(cmd, "-c")) {
248                         if (*argc < 2) {
249                                 fprintf(stderr, _("-c expects a configuration string\n" ));
250                                 usage(git_usage_string);
251                         }
252                         git_config_push_parameter((*argv)[1]);
253                         (*argv)++;
254                         (*argc)--;
255                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
256                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
257                         if (envchanged)
258                                 *envchanged = 1;
259                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
260                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
261                         if (envchanged)
262                                 *envchanged = 1;
263                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
264                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
265                         if (envchanged)
266                                 *envchanged = 1;
267                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
268                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
269                         if (envchanged)
270                                 *envchanged = 1;
271                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
272                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
273                         if (envchanged)
274                                 *envchanged = 1;
275                 } else if (!strcmp(cmd, "--no-optional-locks")) {
276                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
277                         if (envchanged)
278                                 *envchanged = 1;
279                 } else if (!strcmp(cmd, "--shallow-file")) {
280                         (*argv)++;
281                         (*argc)--;
282                         set_alternate_shallow_file(the_repository, (*argv)[0], 1);
283                         if (envchanged)
284                                 *envchanged = 1;
285                 } else if (!strcmp(cmd, "-C")) {
286                         if (*argc < 2) {
287                                 fprintf(stderr, _("no directory given for -C\n" ));
288                                 usage(git_usage_string);
289                         }
290                         if ((*argv)[1][0]) {
291                                 if (chdir((*argv)[1]))
292                                         die_errno("cannot change to '%s'", (*argv)[1]);
293                                 if (envchanged)
294                                         *envchanged = 1;
295                         }
296                         (*argv)++;
297                         (*argc)--;
298                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
299                         trace2_cmd_name("_query_");
300                         if (!strcmp(cmd, "parseopt")) {
301                                 struct string_list list = STRING_LIST_INIT_DUP;
302                                 int i;
303
304                                 list_builtins(&list, NO_PARSEOPT);
305                                 for (i = 0; i < list.nr; i++)
306                                         printf("%s ", list.items[i].string);
307                                 string_list_clear(&list, 0);
308                                 exit(0);
309                         } else {
310                                 exit(list_cmds(cmd));
311                         }
312                 } else {
313                         fprintf(stderr, _("unknown option: %s\n"), cmd);
314                         usage(git_usage_string);
315                 }
316
317                 (*argv)++;
318                 (*argc)--;
319         }
320         return (*argv) - orig_argv;
321 }
322
323 static int handle_alias(int *argcp, const char ***argv)
324 {
325         int envchanged = 0, ret = 0, saved_errno = errno;
326         int count, option_count;
327         const char **new_argv;
328         const char *alias_command;
329         char *alias_string;
330
331         alias_command = (*argv)[0];
332         alias_string = alias_lookup(alias_command);
333         if (alias_string) {
334                 if (*argcp > 1 && !strcmp((*argv)[1], "-h"))
335                         fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
336                                    alias_command, alias_string);
337                 if (alias_string[0] == '!') {
338                         struct child_process child = CHILD_PROCESS_INIT;
339                         int nongit_ok;
340
341                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
342                         setup_git_directory_gently(&nongit_ok);
343
344                         commit_pager_choice();
345
346                         child.use_shell = 1;
347                         child.trace2_child_class = "shell_alias";
348                         argv_array_push(&child.args, alias_string + 1);
349                         argv_array_pushv(&child.args, (*argv) + 1);
350
351                         trace2_cmd_alias(alias_command, child.args.argv);
352                         trace2_cmd_list_config();
353                         trace2_cmd_name("_run_shell_alias_");
354
355                         ret = run_command(&child);
356                         if (ret >= 0)   /* normal exit */
357                                 exit(ret);
358
359                         die_errno(_("while expanding alias '%s': '%s'"),
360                                   alias_command, alias_string + 1);
361                 }
362                 count = split_cmdline(alias_string, &new_argv);
363                 if (count < 0)
364                         die(_("bad alias.%s string: %s"), alias_command,
365                             _(split_cmdline_strerror(count)));
366                 option_count = handle_options(&new_argv, &count, &envchanged);
367                 if (envchanged)
368                         die(_("alias '%s' changes environment variables.\n"
369                               "You can use '!git' in the alias to do this"),
370                             alias_command);
371                 memmove(new_argv - option_count, new_argv,
372                                 count * sizeof(char *));
373                 new_argv -= option_count;
374
375                 if (count < 1)
376                         die(_("empty alias for %s"), alias_command);
377
378                 if (!strcmp(alias_command, new_argv[0]))
379                         die(_("recursive alias: %s"), alias_command);
380
381                 trace_argv_printf(new_argv,
382                                   "trace: alias expansion: %s =>",
383                                   alias_command);
384
385                 REALLOC_ARRAY(new_argv, count + *argcp);
386                 /* insert after command name */
387                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
388
389                 trace2_cmd_alias(alias_command, new_argv);
390                 trace2_cmd_list_config();
391
392                 *argv = new_argv;
393                 *argcp += count - 1;
394
395                 ret = 1;
396         }
397
398         errno = saved_errno;
399
400         return ret;
401 }
402
403 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
404 {
405         int status, help;
406         struct stat st;
407         const char *prefix;
408
409         prefix = NULL;
410         help = argc == 2 && !strcmp(argv[1], "-h");
411         if (!help) {
412                 if (p->option & RUN_SETUP)
413                         prefix = setup_git_directory();
414                 else if (p->option & RUN_SETUP_GENTLY) {
415                         int nongit_ok;
416                         prefix = setup_git_directory_gently(&nongit_ok);
417                 }
418
419                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
420                     !(p->option & DELAY_PAGER_CONFIG))
421                         use_pager = check_pager_config(p->cmd);
422                 if (use_pager == -1 && p->option & USE_PAGER)
423                         use_pager = 1;
424
425                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
426                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
427                         trace_repo_setup(prefix);
428         }
429         commit_pager_choice();
430
431         if (!help && get_super_prefix()) {
432                 if (!(p->option & SUPPORT_SUPER_PREFIX))
433                         die(_("%s doesn't support --super-prefix"), p->cmd);
434         }
435
436         if (!help && p->option & NEED_WORK_TREE)
437                 setup_work_tree();
438
439         trace_argv_printf(argv, "trace: built-in: git");
440         trace2_cmd_name(p->cmd);
441         trace2_cmd_list_config();
442
443         validate_cache_entries(the_repository->index);
444         status = p->fn(argc, argv, prefix);
445         validate_cache_entries(the_repository->index);
446
447         if (status)
448                 return status;
449
450         /* Somebody closed stdout? */
451         if (fstat(fileno(stdout), &st))
452                 return 0;
453         /* Ignore write errors for pipes and sockets.. */
454         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
455                 return 0;
456
457         /* Check for ENOSPC and EIO errors.. */
458         if (fflush(stdout))
459                 die_errno(_("write failure on standard output"));
460         if (ferror(stdout))
461                 die(_("unknown write failure on standard output"));
462         if (fclose(stdout))
463                 die_errno(_("close failed on standard output"));
464         return 0;
465 }
466
467 static struct cmd_struct commands[] = {
468         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
469         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
470         { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
471         { "apply", cmd_apply, RUN_SETUP_GENTLY },
472         { "archive", cmd_archive, RUN_SETUP_GENTLY },
473         { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
474         { "blame", cmd_blame, RUN_SETUP },
475         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
476         { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
477         { "cat-file", cmd_cat_file, RUN_SETUP },
478         { "check-attr", cmd_check_attr, RUN_SETUP },
479         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
480         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
481         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
482         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
483         { "checkout-index", cmd_checkout_index,
484                 RUN_SETUP | NEED_WORK_TREE},
485         { "cherry", cmd_cherry, RUN_SETUP },
486         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
487         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
488         { "clone", cmd_clone },
489         { "column", cmd_column, RUN_SETUP_GENTLY },
490         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
491         { "commit-graph", cmd_commit_graph, RUN_SETUP },
492         { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
493         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
494         { "count-objects", cmd_count_objects, RUN_SETUP },
495         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
496         { "describe", cmd_describe, RUN_SETUP },
497         { "diff", cmd_diff, NO_PARSEOPT },
498         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
499         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
500         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
501         { "difftool", cmd_difftool, RUN_SETUP_GENTLY },
502         { "fast-export", cmd_fast_export, RUN_SETUP },
503         { "fetch", cmd_fetch, RUN_SETUP },
504         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
505         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
506         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
507         { "format-patch", cmd_format_patch, RUN_SETUP },
508         { "fsck", cmd_fsck, RUN_SETUP },
509         { "fsck-objects", cmd_fsck, RUN_SETUP },
510         { "gc", cmd_gc, RUN_SETUP },
511         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
512         { "grep", cmd_grep, RUN_SETUP_GENTLY },
513         { "hash-object", cmd_hash_object },
514         { "help", cmd_help },
515         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
516         { "init", cmd_init_db },
517         { "init-db", cmd_init_db },
518         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
519         { "log", cmd_log, RUN_SETUP },
520         { "ls-files", cmd_ls_files, RUN_SETUP },
521         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
522         { "ls-tree", cmd_ls_tree, RUN_SETUP },
523         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
524         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
525         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
526         { "merge-base", cmd_merge_base, RUN_SETUP },
527         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
528         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
529         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
530         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
531         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
532         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
533         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
534         { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
535         { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
536         { "mktree", cmd_mktree, RUN_SETUP },
537         { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP_GENTLY },
538         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
539         { "name-rev", cmd_name_rev, RUN_SETUP },
540         { "notes", cmd_notes, RUN_SETUP },
541         { "pack-objects", cmd_pack_objects, RUN_SETUP },
542         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
543         { "pack-refs", cmd_pack_refs, RUN_SETUP },
544         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
545         { "pickaxe", cmd_blame, RUN_SETUP },
546         { "prune", cmd_prune, RUN_SETUP },
547         { "prune-packed", cmd_prune_packed, RUN_SETUP },
548         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
549         { "push", cmd_push, RUN_SETUP },
550         { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },
551         { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
552         /*
553          * NEEDSWORK: Until the rebase is independent and needs no redirection
554          * to rebase shell script this is kept as is, then should be changed to
555          * RUN_SETUP | NEED_WORK_TREE
556          */
557         { "rebase", cmd_rebase },
558         { "rebase--interactive", cmd_rebase__interactive, RUN_SETUP | NEED_WORK_TREE },
559         { "receive-pack", cmd_receive_pack },
560         { "reflog", cmd_reflog, RUN_SETUP },
561         { "remote", cmd_remote, RUN_SETUP },
562         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
563         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
564         { "repack", cmd_repack, RUN_SETUP },
565         { "replace", cmd_replace, RUN_SETUP },
566         { "rerere", cmd_rerere, RUN_SETUP },
567         { "reset", cmd_reset, RUN_SETUP },
568         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
569         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
570         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
571         { "rm", cmd_rm, RUN_SETUP },
572         { "send-pack", cmd_send_pack, RUN_SETUP },
573         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
574         { "show", cmd_show, RUN_SETUP },
575         { "show-branch", cmd_show_branch, RUN_SETUP },
576         { "show-index", cmd_show_index },
577         { "show-ref", cmd_show_ref, RUN_SETUP },
578         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
579         /*
580          * NEEDSWORK: Until the builtin stash is thoroughly robust and no
581          * longer needs redirection to the stash shell script this is kept as
582          * is, then should be changed to RUN_SETUP | NEED_WORK_TREE
583          */
584         { "stash", cmd_stash },
585         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
586         { "stripspace", cmd_stripspace },
587         { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
588         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
589         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
590         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
591         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
592         { "update-index", cmd_update_index, RUN_SETUP },
593         { "update-ref", cmd_update_ref, RUN_SETUP },
594         { "update-server-info", cmd_update_server_info, RUN_SETUP },
595         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
596         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
597         { "upload-pack", cmd_upload_pack },
598         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
599         { "verify-commit", cmd_verify_commit, RUN_SETUP },
600         { "verify-pack", cmd_verify_pack },
601         { "verify-tag", cmd_verify_tag, RUN_SETUP },
602         { "version", cmd_version },
603         { "whatchanged", cmd_whatchanged, RUN_SETUP },
604         { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
605         { "write-tree", cmd_write_tree, RUN_SETUP },
606 };
607
608 static struct cmd_struct *get_builtin(const char *s)
609 {
610         int i;
611         for (i = 0; i < ARRAY_SIZE(commands); i++) {
612                 struct cmd_struct *p = commands + i;
613                 if (!strcmp(s, p->cmd))
614                         return p;
615         }
616         return NULL;
617 }
618
619 int is_builtin(const char *s)
620 {
621         return !!get_builtin(s);
622 }
623
624 static void list_builtins(struct string_list *out, unsigned int exclude_option)
625 {
626         int i;
627         for (i = 0; i < ARRAY_SIZE(commands); i++) {
628                 if (exclude_option &&
629                     (commands[i].option & exclude_option))
630                         continue;
631                 string_list_append(out, commands[i].cmd);
632         }
633 }
634
635 #ifdef STRIP_EXTENSION
636 static void strip_extension(const char **argv)
637 {
638         size_t len;
639
640         if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
641                 argv[0] = xmemdupz(argv[0], len);
642 }
643 #else
644 #define strip_extension(cmd)
645 #endif
646
647 static void handle_builtin(int argc, const char **argv)
648 {
649         struct argv_array args = ARGV_ARRAY_INIT;
650         const char *cmd;
651         struct cmd_struct *builtin;
652
653         strip_extension(argv);
654         cmd = argv[0];
655
656         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
657         if (argc > 1 && !strcmp(argv[1], "--help")) {
658                 int i;
659
660                 argv[1] = argv[0];
661                 argv[0] = cmd = "help";
662
663                 for (i = 0; i < argc; i++) {
664                         argv_array_push(&args, argv[i]);
665                         if (!i)
666                                 argv_array_push(&args, "--exclude-guides");
667                 }
668
669                 argc++;
670                 argv = args.argv;
671         }
672
673         builtin = get_builtin(cmd);
674         if (builtin)
675                 exit(run_builtin(builtin, argc, argv));
676         argv_array_clear(&args);
677 }
678
679 static void execv_dashed_external(const char **argv)
680 {
681         struct child_process cmd = CHILD_PROCESS_INIT;
682         int status;
683
684         if (get_super_prefix())
685                 die(_("%s doesn't support --super-prefix"), argv[0]);
686
687         if (use_pager == -1 && !is_builtin(argv[0]))
688                 use_pager = check_pager_config(argv[0]);
689         commit_pager_choice();
690
691         argv_array_pushf(&cmd.args, "git-%s", argv[0]);
692         argv_array_pushv(&cmd.args, argv + 1);
693         cmd.clean_on_exit = 1;
694         cmd.wait_after_clean = 1;
695         cmd.silent_exec_failure = 1;
696         cmd.trace2_child_class = "dashed";
697
698         trace2_cmd_name("_run_dashed_");
699
700         /*
701          * The code in run_command() logs trace2 child_start/child_exit
702          * events, so we do not need to report exec/exec_result events here.
703          */
704         trace_argv_printf(cmd.args.argv, "trace: exec:");
705
706         /*
707          * If we fail because the command is not found, it is
708          * OK to return. Otherwise, we just pass along the status code,
709          * or our usual generic code if we were not even able to exec
710          * the program.
711          */
712         status = run_command(&cmd);
713
714         /*
715          * If the child process ran and we are now going to exit, emit a
716          * generic string as our trace2 command verb to indicate that we
717          * launched a dashed command.
718          */
719         if (status >= 0)
720                 exit(status);
721         else if (errno != ENOENT)
722                 exit(128);
723 }
724
725 static int run_argv(int *argcp, const char ***argv)
726 {
727         int done_alias = 0;
728         struct string_list cmd_list = STRING_LIST_INIT_NODUP;
729         struct string_list_item *seen;
730
731         while (1) {
732                 /*
733                  * If we tried alias and futzed with our environment,
734                  * it no longer is safe to invoke builtins directly in
735                  * general.  We have to spawn them as dashed externals.
736                  *
737                  * NEEDSWORK: if we can figure out cases
738                  * where it is safe to do, we can avoid spawning a new
739                  * process.
740                  */
741                 if (!done_alias)
742                         handle_builtin(*argcp, *argv);
743
744 #if 0 // TODO In GFW, need to amend a7924b655e940b06cb547c235d6bed9767929673 to include trace2_ and _tr2 lines.
745                 else if (get_builtin(**argv)) {
746                         struct argv_array args = ARGV_ARRAY_INIT;
747                         int i;
748
749                         /*
750                          * The current process is committed to launching a
751                          * child process to run the command named in (**argv)
752                          * and exiting.  Log a generic string as the trace2
753                          * command verb to indicate this.  Note that the child
754                          * process will log the actual verb when it runs.
755                          */
756                         trace2_cmd_name("_run_git_alias_");
757
758                         if (get_super_prefix())
759                                 die("%s doesn't support --super-prefix", **argv);
760
761                         commit_pager_choice();
762
763                         argv_array_push(&args, "git");
764                         for (i = 0; i < *argcp; i++)
765                                 argv_array_push(&args, (*argv)[i]);
766
767                         trace_argv_printf(args.argv, "trace: exec:");
768
769                         /*
770                          * if we fail because the command is not found, it is
771                          * OK to return. Otherwise, we just pass along the status code.
772                          */
773                         i = run_command_v_opt_tr2(args.argv, RUN_SILENT_EXEC_FAILURE |
774                                                   RUN_CLEAN_ON_EXIT, "git_alias");
775                         if (i >= 0 || errno != ENOENT)
776                                 exit(i);
777                         die("could not execute builtin %s", **argv);
778                 }
779 #endif // a7924b655e940b06cb547c235d6bed9767929673
780
781                 /* .. then try the external ones */
782                 execv_dashed_external(*argv);
783
784                 seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);
785                 if (seen) {
786                         int i;
787                         struct strbuf sb = STRBUF_INIT;
788                         for (i = 0; i < cmd_list.nr; i++) {
789                                 struct string_list_item *item = &cmd_list.items[i];
790
791                                 strbuf_addf(&sb, "\n  %s", item->string);
792                                 if (item == seen)
793                                         strbuf_addstr(&sb, " <==");
794                                 else if (i == cmd_list.nr - 1)
795                                         strbuf_addstr(&sb, " ==>");
796                         }
797                         die(_("alias loop detected: expansion of '%s' does"
798                               " not terminate:%s"), cmd_list.items[0].string, sb.buf);
799                 }
800
801                 string_list_append(&cmd_list, *argv[0]);
802
803                 /*
804                  * It could be an alias -- this works around the insanity
805                  * of overriding "git log" with "git show" by having
806                  * alias.log = show
807                  */
808                 if (!handle_alias(argcp, argv))
809                         break;
810                 done_alias = 1;
811         }
812
813         string_list_clear(&cmd_list, 0);
814
815         return done_alias;
816 }
817
818 int cmd_main(int argc, const char **argv)
819 {
820         const char *cmd;
821         int done_help = 0;
822
823         cmd = argv[0];
824         if (!cmd)
825                 cmd = "git-help";
826         else {
827                 const char *slash = find_last_dir_sep(cmd);
828                 if (slash)
829                         cmd = slash + 1;
830         }
831
832         trace_command_performance(argv);
833
834         /*
835          * "git-xxxx" is the same as "git xxxx", but we obviously:
836          *
837          *  - cannot take flags in between the "git" and the "xxxx".
838          *  - cannot execute it externally (since it would just do
839          *    the same thing over again)
840          *
841          * So we just directly call the builtin handler, and die if
842          * that one cannot handle it.
843          */
844         if (skip_prefix(cmd, "git-", &cmd)) {
845                 argv[0] = cmd;
846                 handle_builtin(argc, argv);
847                 die(_("cannot handle %s as a builtin"), cmd);
848         }
849
850         /* Look for flags.. */
851         argv++;
852         argc--;
853         handle_options(&argv, &argc, NULL);
854         if (argc > 0) {
855                 /* translate --help and --version into commands */
856                 skip_prefix(argv[0], "--", &argv[0]);
857         } else {
858                 /* The user didn't specify a command; give them help */
859                 commit_pager_choice();
860                 printf(_("usage: %s\n\n"), git_usage_string);
861                 list_common_cmds_help();
862                 printf("\n%s\n", _(git_more_info_string));
863                 exit(1);
864         }
865         cmd = argv[0];
866
867         /*
868          * We use PATH to find git commands, but we prepend some higher
869          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
870          * environment, and the $(gitexecdir) from the Makefile at build
871          * time.
872          */
873         setup_path();
874
875         while (1) {
876                 int was_alias = run_argv(&argc, &argv);
877                 if (errno != ENOENT)
878                         break;
879                 if (was_alias) {
880                         fprintf(stderr, _("expansion of alias '%s' failed; "
881                                           "'%s' is not a git command\n"),
882                                 cmd, argv[0]);
883                         exit(1);
884                 }
885                 if (!done_help) {
886                         cmd = argv[0] = help_unknown_cmd(cmd);
887                         done_help = 1;
888                 } else
889                         break;
890         }
891
892         fprintf(stderr, _("failed to run command '%s': %s\n"),
893                 cmd, strerror(errno));
894
895         return 1;
896 }