Merge branch 'jk/rebase-no-autostash' into maint
[git/git.git] / git.c
1 #include "builtin.h"
2 #include "exec_cmd.h"
3 #include "help.h"
4 #include "run-command.h"
5
6 const char git_usage_string[] =
7 "git [--version] [--help] [-C <path>] [-c name=value]\n"
8 " [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
9 " [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
10 " [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
11 " <command> [<args>]";
12
13 const char git_more_info_string[] =
14 N_("'git help -a' and 'git help -g' list available subcommands and some\n"
15 "concept guides. See 'git help <command>' or 'git help <concept>'\n"
16 "to read about a specific subcommand or concept.");
17
18 static struct startup_info git_startup_info;
19 static int use_pager = -1;
20 static char *orig_cwd;
21 static const char *env_names[] = {
22 GIT_DIR_ENVIRONMENT,
23 GIT_WORK_TREE_ENVIRONMENT,
24 GIT_IMPLICIT_WORK_TREE_ENVIRONMENT,
25 GIT_PREFIX_ENVIRONMENT
26 };
27 static char *orig_env[4];
28 static int saved_environment;
29
30 static void save_env(void)
31 {
32 int i;
33 if (saved_environment)
34 return;
35 saved_environment = 1;
36 orig_cwd = xgetcwd();
37 for (i = 0; i < ARRAY_SIZE(env_names); i++) {
38 orig_env[i] = getenv(env_names[i]);
39 if (orig_env[i])
40 orig_env[i] = xstrdup(orig_env[i]);
41 }
42 }
43
44 static void restore_env(void)
45 {
46 int i;
47 if (orig_cwd && chdir(orig_cwd))
48 die_errno("could not move to %s", orig_cwd);
49 free(orig_cwd);
50 for (i = 0; i < ARRAY_SIZE(env_names); i++) {
51 if (orig_env[i])
52 setenv(env_names[i], orig_env[i], 1);
53 else
54 unsetenv(env_names[i]);
55 }
56 }
57
58 static void commit_pager_choice(void) {
59 switch (use_pager) {
60 case 0:
61 setenv("GIT_PAGER", "cat", 1);
62 break;
63 case 1:
64 setup_pager();
65 break;
66 default:
67 break;
68 }
69 }
70
71 static int handle_options(const char ***argv, int *argc, int *envchanged)
72 {
73 const char **orig_argv = *argv;
74
75 while (*argc > 0) {
76 const char *cmd = (*argv)[0];
77 if (cmd[0] != '-')
78 break;
79
80 /*
81 * For legacy reasons, the "version" and "help"
82 * commands can be written with "--" prepended
83 * to make them look like flags.
84 */
85 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
86 break;
87
88 /*
89 * Check remaining flags.
90 */
91 if (skip_prefix(cmd, "--exec-path", &cmd)) {
92 if (*cmd == '=')
93 git_set_argv_exec_path(cmd + 1);
94 else {
95 puts(git_exec_path());
96 exit(0);
97 }
98 } else if (!strcmp(cmd, "--html-path")) {
99 puts(system_path(GIT_HTML_PATH));
100 exit(0);
101 } else if (!strcmp(cmd, "--man-path")) {
102 puts(system_path(GIT_MAN_PATH));
103 exit(0);
104 } else if (!strcmp(cmd, "--info-path")) {
105 puts(system_path(GIT_INFO_PATH));
106 exit(0);
107 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
108 use_pager = 1;
109 } else if (!strcmp(cmd, "--no-pager")) {
110 use_pager = 0;
111 if (envchanged)
112 *envchanged = 1;
113 } else if (!strcmp(cmd, "--no-replace-objects")) {
114 check_replace_refs = 0;
115 setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
116 if (envchanged)
117 *envchanged = 1;
118 } else if (!strcmp(cmd, "--git-dir")) {
119 if (*argc < 2) {
120 fprintf(stderr, "No directory given for --git-dir.\n" );
121 usage(git_usage_string);
122 }
123 setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
124 if (envchanged)
125 *envchanged = 1;
126 (*argv)++;
127 (*argc)--;
128 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
129 setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
130 if (envchanged)
131 *envchanged = 1;
132 } else if (!strcmp(cmd, "--namespace")) {
133 if (*argc < 2) {
134 fprintf(stderr, "No namespace given for --namespace.\n" );
135 usage(git_usage_string);
136 }
137 setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
138 if (envchanged)
139 *envchanged = 1;
140 (*argv)++;
141 (*argc)--;
142 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
143 setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
144 if (envchanged)
145 *envchanged = 1;
146 } else if (!strcmp(cmd, "--work-tree")) {
147 if (*argc < 2) {
148 fprintf(stderr, "No directory given for --work-tree.\n" );
149 usage(git_usage_string);
150 }
151 setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
152 if (envchanged)
153 *envchanged = 1;
154 (*argv)++;
155 (*argc)--;
156 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
157 setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
158 if (envchanged)
159 *envchanged = 1;
160 } else if (!strcmp(cmd, "--bare")) {
161 char *cwd = xgetcwd();
162 is_bare_repository_cfg = 1;
163 setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
164 free(cwd);
165 setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
166 if (envchanged)
167 *envchanged = 1;
168 } else if (!strcmp(cmd, "-c")) {
169 if (*argc < 2) {
170 fprintf(stderr, "-c expects a configuration string\n" );
171 usage(git_usage_string);
172 }
173 git_config_push_parameter((*argv)[1]);
174 (*argv)++;
175 (*argc)--;
176 } else if (!strcmp(cmd, "--literal-pathspecs")) {
177 setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
178 if (envchanged)
179 *envchanged = 1;
180 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
181 setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
182 if (envchanged)
183 *envchanged = 1;
184 } else if (!strcmp(cmd, "--glob-pathspecs")) {
185 setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
186 if (envchanged)
187 *envchanged = 1;
188 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
189 setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
190 if (envchanged)
191 *envchanged = 1;
192 } else if (!strcmp(cmd, "--icase-pathspecs")) {
193 setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
194 if (envchanged)
195 *envchanged = 1;
196 } else if (!strcmp(cmd, "--shallow-file")) {
197 (*argv)++;
198 (*argc)--;
199 set_alternate_shallow_file((*argv)[0], 1);
200 if (envchanged)
201 *envchanged = 1;
202 } else if (!strcmp(cmd, "-C")) {
203 if (*argc < 2) {
204 fprintf(stderr, "No directory given for -C.\n" );
205 usage(git_usage_string);
206 }
207 if ((*argv)[1][0]) {
208 if (chdir((*argv)[1]))
209 die_errno("Cannot change to '%s'", (*argv)[1]);
210 if (envchanged)
211 *envchanged = 1;
212 }
213 (*argv)++;
214 (*argc)--;
215 } else {
216 fprintf(stderr, "Unknown option: %s\n", cmd);
217 usage(git_usage_string);
218 }
219
220 (*argv)++;
221 (*argc)--;
222 }
223 return (*argv) - orig_argv;
224 }
225
226 static int handle_alias(int *argcp, const char ***argv)
227 {
228 int envchanged = 0, ret = 0, saved_errno = errno;
229 const char *subdir;
230 int count, option_count;
231 const char **new_argv;
232 const char *alias_command;
233 char *alias_string;
234 int unused_nongit;
235
236 subdir = setup_git_directory_gently(&unused_nongit);
237
238 alias_command = (*argv)[0];
239 alias_string = alias_lookup(alias_command);
240 if (alias_string) {
241 if (alias_string[0] == '!') {
242 const char **alias_argv;
243 int argc = *argcp, i;
244
245 commit_pager_choice();
246
247 /* build alias_argv */
248 alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
249 alias_argv[0] = alias_string + 1;
250 for (i = 1; i < argc; ++i)
251 alias_argv[i] = (*argv)[i];
252 alias_argv[argc] = NULL;
253
254 ret = run_command_v_opt(alias_argv, RUN_USING_SHELL);
255 if (ret >= 0) /* normal exit */
256 exit(ret);
257
258 die_errno("While expanding alias '%s': '%s'",
259 alias_command, alias_string + 1);
260 }
261 count = split_cmdline(alias_string, &new_argv);
262 if (count < 0)
263 die("Bad alias.%s string: %s", alias_command,
264 split_cmdline_strerror(count));
265 option_count = handle_options(&new_argv, &count, &envchanged);
266 if (envchanged)
267 die("alias '%s' changes environment variables\n"
268 "You can use '!git' in the alias to do this.",
269 alias_command);
270 memmove(new_argv - option_count, new_argv,
271 count * sizeof(char *));
272 new_argv -= option_count;
273
274 if (count < 1)
275 die("empty alias for %s", alias_command);
276
277 if (!strcmp(alias_command, new_argv[0]))
278 die("recursive alias: %s", alias_command);
279
280 trace_argv_printf(new_argv,
281 "trace: alias expansion: %s =>",
282 alias_command);
283
284 REALLOC_ARRAY(new_argv, count + *argcp);
285 /* insert after command name */
286 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
287
288 *argv = new_argv;
289 *argcp += count - 1;
290
291 ret = 1;
292 }
293
294 if (subdir && chdir(subdir))
295 die_errno("Cannot change to '%s'", subdir);
296
297 errno = saved_errno;
298
299 return ret;
300 }
301
302 #define RUN_SETUP (1<<0)
303 #define RUN_SETUP_GENTLY (1<<1)
304 #define USE_PAGER (1<<2)
305 /*
306 * require working tree to be present -- anything uses this needs
307 * RUN_SETUP for reading from the configuration file.
308 */
309 #define NEED_WORK_TREE (1<<3)
310 #define NO_SETUP (1<<4)
311
312 struct cmd_struct {
313 const char *cmd;
314 int (*fn)(int, const char **, const char *);
315 int option;
316 };
317
318 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
319 {
320 int status, help;
321 struct stat st;
322 const char *prefix;
323
324 prefix = NULL;
325 help = argc == 2 && !strcmp(argv[1], "-h");
326 if (!help) {
327 if (p->option & RUN_SETUP)
328 prefix = setup_git_directory();
329 else if (p->option & RUN_SETUP_GENTLY) {
330 int nongit_ok;
331 prefix = setup_git_directory_gently(&nongit_ok);
332 }
333
334 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
335 use_pager = check_pager_config(p->cmd);
336 if (use_pager == -1 && p->option & USE_PAGER)
337 use_pager = 1;
338
339 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
340 startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
341 trace_repo_setup(prefix);
342 }
343 commit_pager_choice();
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 },
375 { "apply", cmd_apply, RUN_SETUP_GENTLY },
376 { "archive", cmd_archive },
377 { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
378 { "blame", cmd_blame, RUN_SETUP },
379 { "branch", cmd_branch, RUN_SETUP },
380 { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
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 },
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, NO_SETUP },
393 { "column", cmd_column, RUN_SETUP_GENTLY },
394 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
395 { "commit-tree", cmd_commit_tree, RUN_SETUP },
396 { "config", cmd_config, RUN_SETUP_GENTLY },
397 { "count-objects", cmd_count_objects, RUN_SETUP },
398 { "credential", cmd_credential, RUN_SETUP_GENTLY },
399 { "describe", cmd_describe, RUN_SETUP },
400 { "diff", cmd_diff },
401 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
402 { "diff-index", cmd_diff_index, RUN_SETUP },
403 { "diff-tree", cmd_diff_tree, RUN_SETUP },
404 { "fast-export", cmd_fast_export, RUN_SETUP },
405 { "fetch", cmd_fetch, RUN_SETUP },
406 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
407 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
408 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
409 { "format-patch", cmd_format_patch, RUN_SETUP },
410 { "fsck", cmd_fsck, RUN_SETUP },
411 { "fsck-objects", cmd_fsck, RUN_SETUP },
412 { "gc", cmd_gc, RUN_SETUP },
413 { "get-tar-commit-id", cmd_get_tar_commit_id },
414 { "grep", cmd_grep, RUN_SETUP_GENTLY },
415 { "hash-object", cmd_hash_object },
416 { "help", cmd_help },
417 { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
418 { "init", cmd_init_db, NO_SETUP },
419 { "init-db", cmd_init_db, NO_SETUP },
420 { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP },
421 { "log", cmd_log, RUN_SETUP },
422 { "ls-files", cmd_ls_files, RUN_SETUP },
423 { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
424 { "ls-tree", cmd_ls_tree, RUN_SETUP },
425 { "mailinfo", cmd_mailinfo },
426 { "mailsplit", cmd_mailsplit },
427 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
428 { "merge-base", cmd_merge_base, RUN_SETUP },
429 { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
430 { "merge-index", cmd_merge_index, RUN_SETUP },
431 { "merge-ours", cmd_merge_ours, RUN_SETUP },
432 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
433 { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
434 { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
435 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
436 { "merge-tree", cmd_merge_tree, RUN_SETUP },
437 { "mktag", cmd_mktag, RUN_SETUP },
438 { "mktree", cmd_mktree, RUN_SETUP },
439 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
440 { "name-rev", cmd_name_rev, RUN_SETUP },
441 { "notes", cmd_notes, RUN_SETUP },
442 { "pack-objects", cmd_pack_objects, RUN_SETUP },
443 { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
444 { "pack-refs", cmd_pack_refs, RUN_SETUP },
445 { "patch-id", cmd_patch_id },
446 { "pickaxe", cmd_blame, RUN_SETUP },
447 { "prune", cmd_prune, RUN_SETUP },
448 { "prune-packed", cmd_prune_packed, RUN_SETUP },
449 { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
450 { "push", cmd_push, RUN_SETUP },
451 { "read-tree", cmd_read_tree, RUN_SETUP },
452 { "receive-pack", cmd_receive_pack },
453 { "reflog", cmd_reflog, RUN_SETUP },
454 { "remote", cmd_remote, RUN_SETUP },
455 { "remote-ext", cmd_remote_ext },
456 { "remote-fd", cmd_remote_fd },
457 { "repack", cmd_repack, RUN_SETUP },
458 { "replace", cmd_replace, RUN_SETUP },
459 { "rerere", cmd_rerere, RUN_SETUP },
460 { "reset", cmd_reset, RUN_SETUP },
461 { "rev-list", cmd_rev_list, RUN_SETUP },
462 { "rev-parse", cmd_rev_parse },
463 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
464 { "rm", cmd_rm, RUN_SETUP },
465 { "send-pack", cmd_send_pack, RUN_SETUP },
466 { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
467 { "show", cmd_show, RUN_SETUP },
468 { "show-branch", cmd_show_branch, RUN_SETUP },
469 { "show-ref", cmd_show_ref, RUN_SETUP },
470 { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
471 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
472 { "stripspace", cmd_stripspace },
473 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
474 { "tag", cmd_tag, RUN_SETUP },
475 { "unpack-file", cmd_unpack_file, RUN_SETUP },
476 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
477 { "update-index", cmd_update_index, RUN_SETUP },
478 { "update-ref", cmd_update_ref, RUN_SETUP },
479 { "update-server-info", cmd_update_server_info, RUN_SETUP },
480 { "upload-archive", cmd_upload_archive },
481 { "upload-archive--writer", cmd_upload_archive_writer },
482 { "var", cmd_var, RUN_SETUP_GENTLY },
483 { "verify-commit", cmd_verify_commit, RUN_SETUP },
484 { "verify-pack", cmd_verify_pack },
485 { "verify-tag", cmd_verify_tag, RUN_SETUP },
486 { "version", cmd_version },
487 { "whatchanged", cmd_whatchanged, RUN_SETUP },
488 { "worktree", cmd_worktree, RUN_SETUP },
489 { "write-tree", cmd_write_tree, RUN_SETUP },
490 };
491
492 static struct cmd_struct *get_builtin(const char *s)
493 {
494 int i;
495 for (i = 0; i < ARRAY_SIZE(commands); i++) {
496 struct cmd_struct *p = commands + i;
497 if (!strcmp(s, p->cmd))
498 return p;
499 }
500 return NULL;
501 }
502
503 int is_builtin(const char *s)
504 {
505 return !!get_builtin(s);
506 }
507
508 static void handle_builtin(int argc, const char **argv)
509 {
510 const char *cmd = argv[0];
511 int i;
512 static const char ext[] = STRIP_EXTENSION;
513 struct cmd_struct *builtin;
514
515 if (sizeof(ext) > 1) {
516 i = strlen(argv[0]) - strlen(ext);
517 if (i > 0 && !strcmp(argv[0] + i, ext)) {
518 char *argv0 = xstrdup(argv[0]);
519 argv[0] = cmd = argv0;
520 argv0[i] = '\0';
521 }
522 }
523
524 /* Turn "git cmd --help" into "git help cmd" */
525 if (argc > 1 && !strcmp(argv[1], "--help")) {
526 argv[1] = argv[0];
527 argv[0] = cmd = "help";
528 }
529
530 builtin = get_builtin(cmd);
531 if (builtin) {
532 if (saved_environment && (builtin->option & NO_SETUP))
533 restore_env();
534 else
535 exit(run_builtin(builtin, argc, argv));
536 }
537 }
538
539 static void execv_dashed_external(const char **argv)
540 {
541 struct strbuf cmd = STRBUF_INIT;
542 const char *tmp;
543 int status;
544
545 if (use_pager == -1)
546 use_pager = check_pager_config(argv[0]);
547 commit_pager_choice();
548
549 strbuf_addf(&cmd, "git-%s", argv[0]);
550
551 /*
552 * argv[0] must be the git command, but the argv array
553 * belongs to the caller, and may be reused in
554 * subsequent loop iterations. Save argv[0] and
555 * restore it on error.
556 */
557 tmp = argv[0];
558 argv[0] = cmd.buf;
559
560 trace_argv_printf(argv, "trace: exec:");
561
562 /*
563 * if we fail because the command is not found, it is
564 * OK to return. Otherwise, we just pass along the status code.
565 */
566 status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE | RUN_CLEAN_ON_EXIT);
567 if (status >= 0 || errno != ENOENT)
568 exit(status);
569
570 argv[0] = tmp;
571
572 strbuf_release(&cmd);
573 }
574
575 static int run_argv(int *argcp, const char ***argv)
576 {
577 int done_alias = 0;
578
579 while (1) {
580 /* See if it's a builtin */
581 handle_builtin(*argcp, *argv);
582
583 /* .. then try the external ones */
584 execv_dashed_external(*argv);
585
586 /* It could be an alias -- this works around the insanity
587 * of overriding "git log" with "git show" by having
588 * alias.log = show
589 */
590 if (done_alias)
591 break;
592 save_env();
593 if (!handle_alias(argcp, argv))
594 break;
595 done_alias = 1;
596 }
597
598 return done_alias;
599 }
600
601 /*
602 * Many parts of Git have subprograms communicate via pipe, expect the
603 * upstream of a pipe to die with SIGPIPE when the downstream of a
604 * pipe does not need to read all that is written. Some third-party
605 * programs that ignore or block SIGPIPE for their own reason forget
606 * to restore SIGPIPE handling to the default before spawning Git and
607 * break this carefully orchestrated machinery.
608 *
609 * Restore the way SIGPIPE is handled to default, which is what we
610 * expect.
611 */
612 static void restore_sigpipe_to_default(void)
613 {
614 sigset_t unblock;
615
616 sigemptyset(&unblock);
617 sigaddset(&unblock, SIGPIPE);
618 sigprocmask(SIG_UNBLOCK, &unblock, NULL);
619 signal(SIGPIPE, SIG_DFL);
620 }
621
622 int main(int argc, char **av)
623 {
624 const char **argv = (const char **) av;
625 const char *cmd;
626 int done_help = 0;
627
628 startup_info = &git_startup_info;
629
630 cmd = git_extract_argv0_path(argv[0]);
631 if (!cmd)
632 cmd = "git-help";
633
634 /*
635 * Always open file descriptors 0/1/2 to avoid clobbering files
636 * in die(). It also avoids messing up when the pipes are dup'ed
637 * onto stdin/stdout/stderr in the child processes we spawn.
638 */
639 sanitize_stdfds();
640
641 restore_sigpipe_to_default();
642
643 git_setup_gettext();
644
645 trace_command_performance(argv);
646
647 /*
648 * "git-xxxx" is the same as "git xxxx", but we obviously:
649 *
650 * - cannot take flags in between the "git" and the "xxxx".
651 * - cannot execute it externally (since it would just do
652 * the same thing over again)
653 *
654 * So we just directly call the builtin handler, and die if
655 * that one cannot handle it.
656 */
657 if (skip_prefix(cmd, "git-", &cmd)) {
658 argv[0] = cmd;
659 handle_builtin(argc, argv);
660 die("cannot handle %s as a builtin", cmd);
661 }
662
663 /* Look for flags.. */
664 argv++;
665 argc--;
666 handle_options(&argv, &argc, NULL);
667 if (argc > 0) {
668 /* translate --help and --version into commands */
669 skip_prefix(argv[0], "--", &argv[0]);
670 } else {
671 /* The user didn't specify a command; give them help */
672 commit_pager_choice();
673 printf("usage: %s\n\n", git_usage_string);
674 list_common_cmds_help();
675 printf("\n%s\n", _(git_more_info_string));
676 exit(1);
677 }
678 cmd = argv[0];
679
680 /*
681 * We use PATH to find git commands, but we prepend some higher
682 * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
683 * environment, and the $(gitexecdir) from the Makefile at build
684 * time.
685 */
686 setup_path();
687
688 while (1) {
689 int was_alias = run_argv(&argc, &argv);
690 if (errno != ENOENT)
691 break;
692 if (was_alias) {
693 fprintf(stderr, "Expansion of alias '%s' failed; "
694 "'%s' is not a git command\n",
695 cmd, argv[0]);
696 exit(1);
697 }
698 if (!done_help) {
699 cmd = argv[0] = help_unknown_cmd(cmd);
700 done_help = 1;
701 } else
702 break;
703 }
704
705 fprintf(stderr, "Failed to run command '%s': %s\n",
706 cmd, strerror(errno));
707
708 return 1;
709 }