git: protect against unbalanced calls to {save,restore}_env()
[git/git.git] / git.c
CommitLineData
85023577 1#include "builtin.h"
fd5c363d
TF
2#include "exec_cmd.h"
3#include "help.h"
d8e96fd8 4#include "run-command.h"
8e49d503 5
822a7d50 6const char git_usage_string[] =
44e1e4d6 7 "git [--version] [--help] [-C <path>] [-c name=value]\n"
03a0fb0c 8 " [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
9c9b4f2f 9 " [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
a1bea2c1 10 " [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
62b4698e 11 " <command> [<args>]";
822a7d50 12
b7d96819 13const char git_more_info_string[] =
ad5fe377 14 N_("'git help -a' and 'git help -g' list available subcommands and some\n"
73903d0b
PO
15 "concept guides. See 'git help <command>' or 'git help <concept>'\n"
16 "to read about a specific subcommand or concept.");
b7d96819 17
e37c1329 18static struct startup_info git_startup_info;
4e10738a 19static int use_pager = -1;
f655651e 20static char *orig_cwd;
c0562611
NTND
21static const char *env_names[] = {
22 GIT_DIR_ENVIRONMENT,
23 GIT_WORK_TREE_ENVIRONMENT,
24 GIT_IMPLICIT_WORK_TREE_ENVIRONMENT,
25 GIT_PREFIX_ENVIRONMENT
26};
27static char *orig_env[4];
0d5466d2 28static int saved_env_before_alias;
2e1175d4 29static int save_restore_env_balance;
c0562611 30
0d5466d2 31static void save_env_before_alias(void)
c0562611
NTND
32{
33 int i;
0d5466d2 34 saved_env_before_alias = 1;
2e1175d4
JH
35
36 assert(save_restore_env_balance == 0);
37 save_restore_env_balance = 1;
f655651e 38 orig_cwd = xgetcwd();
c0562611
NTND
39 for (i = 0; i < ARRAY_SIZE(env_names); i++) {
40 orig_env[i] = getenv(env_names[i]);
41 if (orig_env[i])
42 orig_env[i] = xstrdup(orig_env[i]);
43 }
44}
45
57ea7123 46static void restore_env(int external_alias)
c0562611
NTND
47{
48 int i;
2e1175d4
JH
49
50 assert(save_restore_env_balance == 1);
51 save_restore_env_balance = 0;
57ea7123 52 if (!external_alias && orig_cwd && chdir(orig_cwd))
c0562611 53 die_errno("could not move to %s", orig_cwd);
f655651e 54 free(orig_cwd);
c0562611 55 for (i = 0; i < ARRAY_SIZE(env_names); i++) {
57ea7123
NTND
56 if (external_alias &&
57 !strcmp(env_names[i], GIT_PREFIX_ENVIRONMENT))
58 continue;
c0562611
NTND
59 if (orig_env[i])
60 setenv(env_names[i], orig_env[i], 1);
61 else
62 unsetenv(env_names[i]);
63 }
64}
4e10738a
JK
65
66static void commit_pager_choice(void) {
67 switch (use_pager) {
68 case 0:
69 setenv("GIT_PAGER", "cat", 1);
70 break;
71 case 1:
72 setup_pager();
73 break;
74 default:
75 break;
76 }
77}
78
4b25d091 79static int handle_options(const char ***argv, int *argc, int *envchanged)
4ab243a9 80{
73546c08 81 const char **orig_argv = *argv;
4ab243a9
JS
82
83 while (*argc > 0) {
84 const char *cmd = (*argv)[0];
85 if (cmd[0] != '-')
86 break;
87
6acbcb92
JS
88 /*
89 * For legacy reasons, the "version" and "help"
90 * commands can be written with "--" prepended
91 * to make them look like flags.
92 */
93 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
94 break;
95
96 /*
97 * Check remaining flags.
98 */
ae021d87 99 if (skip_prefix(cmd, "--exec-path", &cmd)) {
6acbcb92 100 if (*cmd == '=')
384df833 101 git_set_argv_exec_path(cmd + 1);
6acbcb92
JS
102 else {
103 puts(git_exec_path());
104 exit(0);
105 }
89a56bfb
MH
106 } else if (!strcmp(cmd, "--html-path")) {
107 puts(system_path(GIT_HTML_PATH));
108 exit(0);
f2dd8c37
JS
109 } else if (!strcmp(cmd, "--man-path")) {
110 puts(system_path(GIT_MAN_PATH));
111 exit(0);
112 } else if (!strcmp(cmd, "--info-path")) {
113 puts(system_path(GIT_INFO_PATH));
114 exit(0);
6acbcb92 115 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
4e10738a 116 use_pager = 1;
463a849d 117 } else if (!strcmp(cmd, "--no-pager")) {
4e10738a 118 use_pager = 0;
463a849d
MM
119 if (envchanged)
120 *envchanged = 1;
b0fa7ab5 121 } else if (!strcmp(cmd, "--no-replace-objects")) {
afc711b8 122 check_replace_refs = 0;
6476b38b
CC
123 setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
124 if (envchanged)
125 *envchanged = 1;
6acbcb92 126 } else if (!strcmp(cmd, "--git-dir")) {
c321f00d
BG
127 if (*argc < 2) {
128 fprintf(stderr, "No directory given for --git-dir.\n" );
129 usage(git_usage_string);
130 }
45b09794 131 setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
4394efec
ML
132 if (envchanged)
133 *envchanged = 1;
6acbcb92
JS
134 (*argv)++;
135 (*argc)--;
ae021d87
JK
136 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
137 setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
4394efec
ML
138 if (envchanged)
139 *envchanged = 1;
a1bea2c1
JT
140 } else if (!strcmp(cmd, "--namespace")) {
141 if (*argc < 2) {
142 fprintf(stderr, "No namespace given for --namespace.\n" );
143 usage(git_usage_string);
144 }
145 setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
146 if (envchanged)
147 *envchanged = 1;
148 (*argv)++;
149 (*argc)--;
ae021d87
JK
150 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
151 setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
a1bea2c1
JT
152 if (envchanged)
153 *envchanged = 1;
892c41b9
ML
154 } else if (!strcmp(cmd, "--work-tree")) {
155 if (*argc < 2) {
156 fprintf(stderr, "No directory given for --work-tree.\n" );
157 usage(git_usage_string);
158 }
159 setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
4394efec
ML
160 if (envchanged)
161 *envchanged = 1;
892c41b9
ML
162 (*argv)++;
163 (*argc)--;
ae021d87
JK
164 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
165 setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
4394efec
ML
166 if (envchanged)
167 *envchanged = 1;
6acbcb92 168 } else if (!strcmp(cmd, "--bare")) {
4d3ab44d 169 char *cwd = xgetcwd();
6adcca3f 170 is_bare_repository_cfg = 1;
4d3ab44d
RS
171 setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
172 free(cwd);
2cd83d10 173 setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
4394efec
ML
174 if (envchanged)
175 *envchanged = 1;
8b1fa778
AR
176 } else if (!strcmp(cmd, "-c")) {
177 if (*argc < 2) {
178 fprintf(stderr, "-c expects a configuration string\n" );
179 usage(git_usage_string);
180 }
2b64fc89 181 git_config_push_parameter((*argv)[1]);
8b1fa778
AR
182 (*argv)++;
183 (*argc)--;
823ab40f
JK
184 } else if (!strcmp(cmd, "--literal-pathspecs")) {
185 setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
186 if (envchanged)
187 *envchanged = 1;
188 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
189 setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
190 if (envchanged)
191 *envchanged = 1;
bd30c2e4
NTND
192 } else if (!strcmp(cmd, "--glob-pathspecs")) {
193 setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
194 if (envchanged)
195 *envchanged = 1;
196 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
197 setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
198 if (envchanged)
199 *envchanged = 1;
93d93537
NTND
200 } else if (!strcmp(cmd, "--icase-pathspecs")) {
201 setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
202 if (envchanged)
203 *envchanged = 1;
6035d6aa
NTND
204 } else if (!strcmp(cmd, "--shallow-file")) {
205 (*argv)++;
206 (*argc)--;
069c0532 207 set_alternate_shallow_file((*argv)[0], 1);
6035d6aa
NTND
208 if (envchanged)
209 *envchanged = 1;
44e1e4d6
NR
210 } else if (!strcmp(cmd, "-C")) {
211 if (*argc < 2) {
212 fprintf(stderr, "No directory given for -C.\n" );
213 usage(git_usage_string);
214 }
6a536e20
KN
215 if ((*argv)[1][0]) {
216 if (chdir((*argv)[1]))
217 die_errno("Cannot change to '%s'", (*argv)[1]);
218 if (envchanged)
219 *envchanged = 1;
220 }
44e1e4d6
NR
221 (*argv)++;
222 (*argc)--;
6acbcb92
JS
223 } else {
224 fprintf(stderr, "Unknown option: %s\n", cmd);
822a7d50 225 usage(git_usage_string);
6acbcb92 226 }
4ab243a9
JS
227
228 (*argv)++;
229 (*argc)--;
4ab243a9 230 }
73546c08 231 return (*argv) - orig_argv;
4ab243a9
JS
232}
233
2b11e317
JS
234static int handle_alias(int *argcp, const char ***argv)
235{
af05d679 236 int envchanged = 0, ret = 0, saved_errno = errno;
0347a8c7 237 int count, option_count;
4b25d091 238 const char **new_argv;
94351118
JK
239 const char *alias_command;
240 char *alias_string;
e85dc0a3 241 int unused_nongit;
2b11e317 242
0d5466d2 243 save_env_before_alias();
86d26f24 244 setup_git_directory_gently(&unused_nongit);
0347a8c7
ML
245
246 alias_command = (*argv)[0];
94351118 247 alias_string = alias_lookup(alias_command);
0347a8c7 248 if (alias_string) {
dfd42a3c 249 if (alias_string[0] == '!') {
7f51f8bc
EFL
250 const char **alias_argv;
251 int argc = *argcp, i;
252
030149a4 253 commit_pager_choice();
57ea7123 254 restore_env(1);
7f51f8bc
EFL
255
256 /* build alias_argv */
257 alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
258 alias_argv[0] = alias_string + 1;
259 for (i = 1; i < argc; ++i)
260 alias_argv[i] = (*argv)[i];
261 alias_argv[argc] = NULL;
262
26b05251 263 ret = run_command_v_opt(alias_argv, RUN_USING_SHELL);
7f51f8bc
EFL
264 if (ret >= 0) /* normal exit */
265 exit(ret);
266
267 die_errno("While expanding alias '%s': '%s'",
268 alias_command, alias_string + 1);
dfd42a3c 269 }
0347a8c7 270 count = split_cmdline(alias_string, &new_argv);
dc4179f9 271 if (count < 0)
ad9ac6db
GB
272 die("Bad alias.%s string: %s", alias_command,
273 split_cmdline_strerror(count));
4394efec
ML
274 option_count = handle_options(&new_argv, &count, &envchanged);
275 if (envchanged)
276 die("alias '%s' changes environment variables\n"
277 "You can use '!git' in the alias to do this.",
278 alias_command);
0347a8c7
ML
279 memmove(new_argv - option_count, new_argv,
280 count * sizeof(char *));
281 new_argv -= option_count;
282
283 if (count < 1)
284 die("empty alias for %s", alias_command);
285
286 if (!strcmp(alias_command, new_argv[0]))
287 die("recursive alias: %s", alias_command);
288
b319ce4c 289 trace_argv_printf(new_argv,
6ce4e61f
CC
290 "trace: alias expansion: %s =>",
291 alias_command);
575ba9d6 292
2756ca43 293 REALLOC_ARRAY(new_argv, count + *argcp);
0347a8c7 294 /* insert after command name */
4b25d091 295 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
2b11e317 296
0347a8c7
ML
297 *argv = new_argv;
298 *argcp += count - 1;
2b11e317 299
0347a8c7 300 ret = 1;
2b11e317
JS
301 }
302
57ea7123 303 restore_env(0);
2b11e317 304
47e5c0ca
JS
305 errno = saved_errno;
306
2b11e317
JS
307 return ret;
308}
309
ee38dfb8
NTND
310#define RUN_SETUP (1<<0)
311#define RUN_SETUP_GENTLY (1<<1)
312#define USE_PAGER (1<<2)
7eff28a9
SP
313/*
314 * require working tree to be present -- anything uses this needs
315 * RUN_SETUP for reading from the configuration file.
316 */
ee38dfb8 317#define NEED_WORK_TREE (1<<3)
a633fca0 318
47d0b4ff
LT
319struct cmd_struct {
320 const char *cmd;
321 int (*fn)(int, const char **, const char *);
322 int option;
323};
324
f172f334 325static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
47d0b4ff 326{
99caeed0 327 int status, help;
0f157315 328 struct stat st;
47d0b4ff
LT
329 const char *prefix;
330
331 prefix = NULL;
99caeed0
JN
332 help = argc == 2 && !strcmp(argv[1], "-h");
333 if (!help) {
334 if (p->option & RUN_SETUP)
335 prefix = setup_git_directory();
27bd38d4 336 else if (p->option & RUN_SETUP_GENTLY) {
ee38dfb8
NTND
337 int nongit_ok;
338 prefix = setup_git_directory_gently(&nongit_ok);
339 }
99caeed0 340
ee38dfb8 341 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
99caeed0
JN
342 use_pager = check_pager_config(p->cmd);
343 if (use_pager == -1 && p->option & USE_PAGER)
344 use_pager = 1;
a9ca8a85
NTND
345
346 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
347 startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
348 trace_repo_setup(prefix);
99caeed0 349 }
4e10738a
JK
350 commit_pager_choice();
351
99caeed0 352 if (!help && p->option & NEED_WORK_TREE)
59f0f2f3
MH
353 setup_work_tree();
354
b319ce4c 355 trace_argv_printf(argv, "trace: built-in: git");
47d0b4ff 356
0f157315
LT
357 status = p->fn(argc, argv, prefix);
358 if (status)
47e3de0e 359 return status;
0f157315
LT
360
361 /* Somebody closed stdout? */
362 if (fstat(fileno(stdout), &st))
363 return 0;
364 /* Ignore write errors for pipes and sockets.. */
365 if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
366 return 0;
367
368 /* Check for ENOSPC and EIO errors.. */
0227f988 369 if (fflush(stdout))
d824cbba 370 die_errno("write failure on standard output");
0227f988
LT
371 if (ferror(stdout))
372 die("unknown write failure on standard output");
373 if (fclose(stdout))
d824cbba 374 die_errno("close failed on standard output");
0f157315 375 return 0;
47d0b4ff
LT
376}
377
c6127fa3
SS
378static struct cmd_struct commands[] = {
379 { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
380 { "annotate", cmd_annotate, RUN_SETUP },
381 { "apply", cmd_apply, RUN_SETUP_GENTLY },
382 { "archive", cmd_archive },
383 { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
384 { "blame", cmd_blame, RUN_SETUP },
385 { "branch", cmd_branch, RUN_SETUP },
386 { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
387 { "cat-file", cmd_cat_file, RUN_SETUP },
388 { "check-attr", cmd_check_attr, RUN_SETUP },
389 { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
390 { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
391 { "check-ref-format", cmd_check_ref_format },
0ca560cb 392 { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
c6127fa3
SS
393 { "checkout-index", cmd_checkout_index,
394 RUN_SETUP | NEED_WORK_TREE},
395 { "cherry", cmd_cherry, RUN_SETUP },
396 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
397 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
86d26f24 398 { "clone", cmd_clone },
c6127fa3
SS
399 { "column", cmd_column, RUN_SETUP_GENTLY },
400 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
401 { "commit-tree", cmd_commit_tree, RUN_SETUP },
402 { "config", cmd_config, RUN_SETUP_GENTLY },
403 { "count-objects", cmd_count_objects, RUN_SETUP },
404 { "credential", cmd_credential, RUN_SETUP_GENTLY },
405 { "describe", cmd_describe, RUN_SETUP },
406 { "diff", cmd_diff },
407 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
408 { "diff-index", cmd_diff_index, RUN_SETUP },
409 { "diff-tree", cmd_diff_tree, RUN_SETUP },
410 { "fast-export", cmd_fast_export, RUN_SETUP },
411 { "fetch", cmd_fetch, RUN_SETUP },
412 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
413 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
414 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
415 { "format-patch", cmd_format_patch, RUN_SETUP },
416 { "fsck", cmd_fsck, RUN_SETUP },
417 { "fsck-objects", cmd_fsck, RUN_SETUP },
418 { "gc", cmd_gc, RUN_SETUP },
419 { "get-tar-commit-id", cmd_get_tar_commit_id },
420 { "grep", cmd_grep, RUN_SETUP_GENTLY },
421 { "hash-object", cmd_hash_object },
422 { "help", cmd_help },
423 { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
86d26f24
NTND
424 { "init", cmd_init_db },
425 { "init-db", cmd_init_db },
6634f054 426 { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP },
c6127fa3
SS
427 { "log", cmd_log, RUN_SETUP },
428 { "ls-files", cmd_ls_files, RUN_SETUP },
429 { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
430 { "ls-tree", cmd_ls_tree, RUN_SETUP },
431 { "mailinfo", cmd_mailinfo },
432 { "mailsplit", cmd_mailsplit },
433 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
434 { "merge-base", cmd_merge_base, RUN_SETUP },
435 { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
436 { "merge-index", cmd_merge_index, RUN_SETUP },
437 { "merge-ours", cmd_merge_ours, RUN_SETUP },
438 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
439 { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
440 { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
441 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
442 { "merge-tree", cmd_merge_tree, RUN_SETUP },
443 { "mktag", cmd_mktag, RUN_SETUP },
444 { "mktree", cmd_mktree, RUN_SETUP },
445 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
446 { "name-rev", cmd_name_rev, RUN_SETUP },
447 { "notes", cmd_notes, RUN_SETUP },
448 { "pack-objects", cmd_pack_objects, RUN_SETUP },
449 { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
450 { "pack-refs", cmd_pack_refs, RUN_SETUP },
451 { "patch-id", cmd_patch_id },
452 { "pickaxe", cmd_blame, RUN_SETUP },
453 { "prune", cmd_prune, RUN_SETUP },
454 { "prune-packed", cmd_prune_packed, RUN_SETUP },
455 { "push", cmd_push, RUN_SETUP },
456 { "read-tree", cmd_read_tree, RUN_SETUP },
457 { "receive-pack", cmd_receive_pack },
458 { "reflog", cmd_reflog, RUN_SETUP },
459 { "remote", cmd_remote, RUN_SETUP },
460 { "remote-ext", cmd_remote_ext },
461 { "remote-fd", cmd_remote_fd },
462 { "repack", cmd_repack, RUN_SETUP },
463 { "replace", cmd_replace, RUN_SETUP },
464 { "rerere", cmd_rerere, RUN_SETUP },
465 { "reset", cmd_reset, RUN_SETUP },
466 { "rev-list", cmd_rev_list, RUN_SETUP },
467 { "rev-parse", cmd_rev_parse },
468 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
469 { "rm", cmd_rm, RUN_SETUP },
470 { "send-pack", cmd_send_pack, RUN_SETUP },
471 { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
472 { "show", cmd_show, RUN_SETUP },
473 { "show-branch", cmd_show_branch, RUN_SETUP },
474 { "show-ref", cmd_show_ref, RUN_SETUP },
475 { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
476 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
477 { "stripspace", cmd_stripspace },
478 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
479 { "tag", cmd_tag, RUN_SETUP },
480 { "unpack-file", cmd_unpack_file, RUN_SETUP },
481 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
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 },
486 { "upload-archive--writer", cmd_upload_archive_writer },
487 { "var", cmd_var, RUN_SETUP_GENTLY },
d07b00b7 488 { "verify-commit", cmd_verify_commit, RUN_SETUP },
c6127fa3
SS
489 { "verify-pack", cmd_verify_pack },
490 { "verify-tag", cmd_verify_tag, RUN_SETUP },
491 { "version", cmd_version },
492 { "whatchanged", cmd_whatchanged, RUN_SETUP },
df0b6cfb 493 { "worktree", cmd_worktree, RUN_SETUP },
c6127fa3
SS
494 { "write-tree", cmd_write_tree, RUN_SETUP },
495};
496
c4f901d1 497static struct cmd_struct *get_builtin(const char *s)
c6127fa3
SS
498{
499 int i;
500 for (i = 0; i < ARRAY_SIZE(commands); i++) {
c4f901d1 501 struct cmd_struct *p = commands + i;
c6127fa3 502 if (!strcmp(s, p->cmd))
c4f901d1 503 return p;
c6127fa3 504 }
c4f901d1
SV
505 return NULL;
506}
507
508int is_builtin(const char *s)
509{
510 return !!get_builtin(s);
c6127fa3
SS
511}
512
3f784a4d 513static void handle_builtin(int argc, const char **argv)
231af832
LT
514{
515 const char *cmd = argv[0];
231af832 516 int i;
23326d14 517 static const char ext[] = STRIP_EXTENSION;
c4f901d1 518 struct cmd_struct *builtin;
23326d14
JS
519
520 if (sizeof(ext) > 1) {
521 i = strlen(argv[0]) - strlen(ext);
522 if (i > 0 && !strcmp(argv[0] + i, ext)) {
e8eec71d 523 char *argv0 = xstrdup(argv[0]);
23326d14
JS
524 argv[0] = cmd = argv0;
525 argv0[i] = '\0';
526 }
527 }
231af832 528
1cd95087
LT
529 /* Turn "git cmd --help" into "git help cmd" */
530 if (argc > 1 && !strcmp(argv[1], "--help")) {
531 argv[1] = argv[0];
532 argv[0] = cmd = "help";
533 }
534
c4f901d1
SV
535 builtin = get_builtin(cmd);
536 if (builtin) {
86d26f24
NTND
537 /*
538 * XXX: if we can figure out cases where it is _safe_
539 * to do, we can avoid spawning a new process when
540 * saved_env_before_alias is true
541 * (i.e. setup_git_dir* has been run once)
542 */
543 if (!saved_env_before_alias)
c4f901d1 544 exit(run_builtin(builtin, argc, argv));
231af832
LT
545 }
546}
547
7550be0a
JH
548static void execv_dashed_external(const char **argv)
549{
f285a2d7 550 struct strbuf cmd = STRBUF_INIT;
7550be0a 551 const char *tmp;
d8e96fd8 552 int status;
7550be0a 553
92058e4d
JK
554 if (use_pager == -1)
555 use_pager = check_pager_config(argv[0]);
030149a4
JN
556 commit_pager_choice();
557
7550be0a
JH
558 strbuf_addf(&cmd, "git-%s", argv[0]);
559
560 /*
561 * argv[0] must be the git command, but the argv array
562 * belongs to the caller, and may be reused in
563 * subsequent loop iterations. Save argv[0] and
564 * restore it on error.
565 */
566 tmp = argv[0];
567 argv[0] = cmd.buf;
568
569 trace_argv_printf(argv, "trace: exec:");
570
d8e96fd8
JK
571 /*
572 * if we fail because the command is not found, it is
573 * OK to return. Otherwise, we just pass along the status code.
574 */
10c6cddd 575 status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE | RUN_CLEAN_ON_EXIT);
0ac77ec3 576 if (status >= 0 || errno != ENOENT)
5709e036 577 exit(status);
7550be0a
JH
578
579 argv[0] = tmp;
580
581 strbuf_release(&cmd);
582}
583
a907e1b6
AS
584static int run_argv(int *argcp, const char ***argv)
585{
586 int done_alias = 0;
587
588 while (1) {
3f784a4d
SS
589 /* See if it's a builtin */
590 handle_builtin(*argcp, *argv);
a907e1b6
AS
591
592 /* .. then try the external ones */
593 execv_dashed_external(*argv);
594
595 /* It could be an alias -- this works around the insanity
596 * of overriding "git log" with "git show" by having
597 * alias.log = show
598 */
c0562611
NTND
599 if (done_alias)
600 break;
c0562611 601 if (!handle_alias(argcp, argv))
a907e1b6
AS
602 break;
603 done_alias = 1;
604 }
605
606 return done_alias;
607}
608
7559a1be
PR
609/*
610 * Many parts of Git have subprograms communicate via pipe, expect the
611 * upstream of a pipe to die with SIGPIPE when the downstream of a
612 * pipe does not need to read all that is written. Some third-party
613 * programs that ignore or block SIGPIPE for their own reason forget
614 * to restore SIGPIPE handling to the default before spawning Git and
615 * break this carefully orchestrated machinery.
616 *
617 * Restore the way SIGPIPE is handled to default, which is what we
618 * expect.
619 */
620static void restore_sigpipe_to_default(void)
621{
622 sigset_t unblock;
623
624 sigemptyset(&unblock);
625 sigaddset(&unblock, SIGPIPE);
626 sigprocmask(SIG_UNBLOCK, &unblock, NULL);
627 signal(SIGPIPE, SIG_DFL);
628}
7550be0a 629
84d32bf7 630int main(int argc, char **av)
8e49d503 631{
84d32bf7 632 const char **argv = (const char **) av;
4dd47c3b 633 const char *cmd;
8fa7975b 634 int done_help = 0;
231af832 635
e37c1329
NTND
636 startup_info = &git_startup_info;
637
2cd72b0b
SP
638 cmd = git_extract_argv0_path(argv[0]);
639 if (!cmd)
4dd47c3b 640 cmd = "git-help";
8e49d503 641
a11c3964
TR
642 /*
643 * Always open file descriptors 0/1/2 to avoid clobbering files
644 * in die(). It also avoids messing up when the pipes are dup'ed
645 * onto stdin/stdout/stderr in the child processes we spawn.
646 */
647 sanitize_stdfds();
648
7559a1be
PR
649 restore_sigpipe_to_default();
650
5e9637c6
ÆAB
651 git_setup_gettext();
652
578da039
KB
653 trace_command_performance(argv);
654
231af832
LT
655 /*
656 * "git-xxxx" is the same as "git xxxx", but we obviously:
657 *
658 * - cannot take flags in between the "git" and the "xxxx".
659 * - cannot execute it externally (since it would just do
660 * the same thing over again)
661 *
3f784a4d
SS
662 * So we just directly call the builtin handler, and die if
663 * that one cannot handle it.
231af832 664 */
ae021d87 665 if (skip_prefix(cmd, "git-", &cmd)) {
231af832 666 argv[0] = cmd;
3f784a4d
SS
667 handle_builtin(argc, argv);
668 die("cannot handle %s as a builtin", cmd);
231af832 669 }
8e49d503 670
231af832 671 /* Look for flags.. */
6acbcb92
JS
672 argv++;
673 argc--;
4394efec 674 handle_options(&argv, &argc, NULL);
6acbcb92 675 if (argc > 0) {
6d877803
JK
676 /* translate --help and --version into commands */
677 skip_prefix(argv[0], "--", &argv[0]);
6acbcb92 678 } else {
3d7e2d85 679 /* The user didn't specify a command; give them help */
73e25e7c 680 commit_pager_choice();
3d7e2d85
SP
681 printf("usage: %s\n\n", git_usage_string);
682 list_common_cmds_help();
421a9769 683 printf("\n%s\n", _(git_more_info_string));
3d7e2d85 684 exit(1);
97fc6c5f 685 }
6acbcb92 686 cmd = argv[0];
231af832
LT
687
688 /*
511707d4 689 * We use PATH to find git commands, but we prepend some higher
3ea3c215 690 * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
511707d4
SP
691 * environment, and the $(gitexecdir) from the Makefile at build
692 * time.
231af832 693 */
e1464ca7 694 setup_path();
8e49d503 695
a025463b 696 while (1) {
8fa7975b 697 int was_alias = run_argv(&argc, &argv);
a907e1b6 698 if (errno != ENOENT)
a025463b 699 break;
a907e1b6 700 if (was_alias) {
f3dd015c 701 fprintf(stderr, "Expansion of alias '%s' failed; "
7283bbc7 702 "'%s' is not a git command\n",
f3dd015c
TT
703 cmd, argv[0]);
704 exit(1);
705 }
a907e1b6
AS
706 if (!done_help) {
707 cmd = argv[0] = help_unknown_cmd(cmd);
708 done_help = 1;
709 } else
710 break;
f3dd015c 711 }
10b15b86
AR
712
713 fprintf(stderr, "Failed to run command '%s': %s\n",
33ebb871 714 cmd, strerror(errno));
8e49d503
AE
715
716 return 1;
717}