Refactor git_set_argv0_path() to git_extract_argv0_path()
[git/git.git] / git.c
1 #include "builtin.h"
2 #include "exec_cmd.h"
3 #include "cache.h"
4 #include "quote.h"
5
6 const char git_usage_string[] =
7 "git [--version] [--exec-path[=GIT_EXEC_PATH]] [-p|--paginate|--no-pager] [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE] [--help] COMMAND [ARGS]";
8
9 const char git_more_info_string[] =
10 "See 'git help COMMAND' for more information on a specific command.";
11
12 static int use_pager = -1;
13 struct pager_config {
14 const char *cmd;
15 int val;
16 };
17
18 static int pager_command_config(const char *var, const char *value, void *data)
19 {
20 struct pager_config *c = data;
21 if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
22 c->val = git_config_bool(var, value);
23 return 0;
24 }
25
26 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
27 int check_pager_config(const char *cmd)
28 {
29 struct pager_config c;
30 c.cmd = cmd;
31 c.val = -1;
32 git_config(pager_command_config, &c);
33 return c.val;
34 }
35
36 static void commit_pager_choice(void) {
37 switch (use_pager) {
38 case 0:
39 setenv("GIT_PAGER", "cat", 1);
40 break;
41 case 1:
42 setup_pager();
43 break;
44 default:
45 break;
46 }
47 }
48
49 static int handle_options(const char*** argv, int* argc, int* envchanged)
50 {
51 int handled = 0;
52
53 while (*argc > 0) {
54 const char *cmd = (*argv)[0];
55 if (cmd[0] != '-')
56 break;
57
58 /*
59 * For legacy reasons, the "version" and "help"
60 * commands can be written with "--" prepended
61 * to make them look like flags.
62 */
63 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
64 break;
65
66 /*
67 * Check remaining flags.
68 */
69 if (!prefixcmp(cmd, "--exec-path")) {
70 cmd += 11;
71 if (*cmd == '=')
72 git_set_argv_exec_path(cmd + 1);
73 else {
74 puts(git_exec_path());
75 exit(0);
76 }
77 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
78 use_pager = 1;
79 } else if (!strcmp(cmd, "--no-pager")) {
80 use_pager = 0;
81 if (envchanged)
82 *envchanged = 1;
83 } else if (!strcmp(cmd, "--git-dir")) {
84 if (*argc < 2) {
85 fprintf(stderr, "No directory given for --git-dir.\n" );
86 usage(git_usage_string);
87 }
88 setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
89 if (envchanged)
90 *envchanged = 1;
91 (*argv)++;
92 (*argc)--;
93 handled++;
94 } else if (!prefixcmp(cmd, "--git-dir=")) {
95 setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
96 if (envchanged)
97 *envchanged = 1;
98 } else if (!strcmp(cmd, "--work-tree")) {
99 if (*argc < 2) {
100 fprintf(stderr, "No directory given for --work-tree.\n" );
101 usage(git_usage_string);
102 }
103 setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
104 if (envchanged)
105 *envchanged = 1;
106 (*argv)++;
107 (*argc)--;
108 } else if (!prefixcmp(cmd, "--work-tree=")) {
109 setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
110 if (envchanged)
111 *envchanged = 1;
112 } else if (!strcmp(cmd, "--bare")) {
113 static char git_dir[PATH_MAX+1];
114 is_bare_repository_cfg = 1;
115 setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
116 if (envchanged)
117 *envchanged = 1;
118 } else {
119 fprintf(stderr, "Unknown option: %s\n", cmd);
120 usage(git_usage_string);
121 }
122
123 (*argv)++;
124 (*argc)--;
125 handled++;
126 }
127 return handled;
128 }
129
130 static int handle_alias(int *argcp, const char ***argv)
131 {
132 int envchanged = 0, ret = 0, saved_errno = errno;
133 const char *subdir;
134 int count, option_count;
135 const char** new_argv;
136 const char *alias_command;
137 char *alias_string;
138 int unused_nongit;
139
140 subdir = setup_git_directory_gently(&unused_nongit);
141
142 alias_command = (*argv)[0];
143 alias_string = alias_lookup(alias_command);
144 if (alias_string) {
145 if (alias_string[0] == '!') {
146 if (*argcp > 1) {
147 struct strbuf buf;
148
149 strbuf_init(&buf, PATH_MAX);
150 strbuf_addstr(&buf, alias_string);
151 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
152 free(alias_string);
153 alias_string = buf.buf;
154 }
155 trace_printf("trace: alias to shell cmd: %s => %s\n",
156 alias_command, alias_string + 1);
157 ret = system(alias_string + 1);
158 if (ret >= 0 && WIFEXITED(ret) &&
159 WEXITSTATUS(ret) != 127)
160 exit(WEXITSTATUS(ret));
161 die("Failed to run '%s' when expanding alias '%s'",
162 alias_string + 1, alias_command);
163 }
164 count = split_cmdline(alias_string, &new_argv);
165 if (count < 0)
166 die("Bad alias.%s string", alias_command);
167 option_count = handle_options(&new_argv, &count, &envchanged);
168 if (envchanged)
169 die("alias '%s' changes environment variables\n"
170 "You can use '!git' in the alias to do this.",
171 alias_command);
172 memmove(new_argv - option_count, new_argv,
173 count * sizeof(char *));
174 new_argv -= option_count;
175
176 if (count < 1)
177 die("empty alias for %s", alias_command);
178
179 if (!strcmp(alias_command, new_argv[0]))
180 die("recursive alias: %s", alias_command);
181
182 trace_argv_printf(new_argv,
183 "trace: alias expansion: %s =>",
184 alias_command);
185
186 new_argv = xrealloc(new_argv, sizeof(char*) *
187 (count + *argcp + 1));
188 /* insert after command name */
189 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
190 new_argv[count+*argcp] = NULL;
191
192 *argv = new_argv;
193 *argcp += count - 1;
194
195 ret = 1;
196 }
197
198 if (subdir && chdir(subdir))
199 die("Cannot change to %s: %s", subdir, strerror(errno));
200
201 errno = saved_errno;
202
203 return ret;
204 }
205
206 const char git_version_string[] = GIT_VERSION;
207
208 #define RUN_SETUP (1<<0)
209 #define USE_PAGER (1<<1)
210 /*
211 * require working tree to be present -- anything uses this needs
212 * RUN_SETUP for reading from the configuration file.
213 */
214 #define NEED_WORK_TREE (1<<2)
215
216 struct cmd_struct {
217 const char *cmd;
218 int (*fn)(int, const char **, const char *);
219 int option;
220 };
221
222 static int run_command(struct cmd_struct *p, int argc, const char **argv)
223 {
224 int status;
225 struct stat st;
226 const char *prefix;
227
228 prefix = NULL;
229 if (p->option & RUN_SETUP)
230 prefix = setup_git_directory();
231
232 if (use_pager == -1 && p->option & RUN_SETUP)
233 use_pager = check_pager_config(p->cmd);
234 if (use_pager == -1 && p->option & USE_PAGER)
235 use_pager = 1;
236 commit_pager_choice();
237
238 if (p->option & NEED_WORK_TREE)
239 setup_work_tree();
240
241 trace_argv_printf(argv, "trace: built-in: git");
242
243 status = p->fn(argc, argv, prefix);
244 if (status)
245 return status & 0xff;
246
247 /* Somebody closed stdout? */
248 if (fstat(fileno(stdout), &st))
249 return 0;
250 /* Ignore write errors for pipes and sockets.. */
251 if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
252 return 0;
253
254 /* Check for ENOSPC and EIO errors.. */
255 if (fflush(stdout))
256 die("write failure on standard output: %s", strerror(errno));
257 if (ferror(stdout))
258 die("unknown write failure on standard output");
259 if (fclose(stdout))
260 die("close failed on standard output: %s", strerror(errno));
261 return 0;
262 }
263
264 static void handle_internal_command(int argc, const char **argv)
265 {
266 const char *cmd = argv[0];
267 static struct cmd_struct commands[] = {
268 { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
269 { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
270 { "annotate", cmd_annotate, RUN_SETUP },
271 { "apply", cmd_apply },
272 { "archive", cmd_archive },
273 { "blame", cmd_blame, RUN_SETUP },
274 { "branch", cmd_branch, RUN_SETUP },
275 { "bundle", cmd_bundle },
276 { "cat-file", cmd_cat_file, RUN_SETUP },
277 { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
278 { "checkout-index", cmd_checkout_index,
279 RUN_SETUP | NEED_WORK_TREE},
280 { "check-ref-format", cmd_check_ref_format },
281 { "check-attr", cmd_check_attr, RUN_SETUP },
282 { "cherry", cmd_cherry, RUN_SETUP },
283 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
284 { "clone", cmd_clone },
285 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
286 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
287 { "commit-tree", cmd_commit_tree, RUN_SETUP },
288 { "config", cmd_config },
289 { "count-objects", cmd_count_objects, RUN_SETUP },
290 { "describe", cmd_describe, RUN_SETUP },
291 { "diff", cmd_diff },
292 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
293 { "diff-index", cmd_diff_index, RUN_SETUP },
294 { "diff-tree", cmd_diff_tree, RUN_SETUP },
295 { "fast-export", cmd_fast_export, RUN_SETUP },
296 { "fetch", cmd_fetch, RUN_SETUP },
297 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
298 { "fetch--tool", cmd_fetch__tool, RUN_SETUP },
299 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
300 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
301 { "format-patch", cmd_format_patch, RUN_SETUP },
302 { "fsck", cmd_fsck, RUN_SETUP },
303 { "fsck-objects", cmd_fsck, RUN_SETUP },
304 { "gc", cmd_gc, RUN_SETUP },
305 { "get-tar-commit-id", cmd_get_tar_commit_id },
306 { "grep", cmd_grep, RUN_SETUP | USE_PAGER },
307 { "help", cmd_help },
308 #ifndef NO_CURL
309 { "http-fetch", cmd_http_fetch, RUN_SETUP },
310 #endif
311 { "init", cmd_init_db },
312 { "init-db", cmd_init_db },
313 { "log", cmd_log, RUN_SETUP | USE_PAGER },
314 { "ls-files", cmd_ls_files, RUN_SETUP },
315 { "ls-tree", cmd_ls_tree, RUN_SETUP },
316 { "ls-remote", cmd_ls_remote },
317 { "mailinfo", cmd_mailinfo },
318 { "mailsplit", cmd_mailsplit },
319 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
320 { "merge-base", cmd_merge_base, RUN_SETUP },
321 { "merge-file", cmd_merge_file },
322 { "merge-ours", cmd_merge_ours, RUN_SETUP },
323 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
324 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
325 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
326 { "name-rev", cmd_name_rev, RUN_SETUP },
327 { "pack-objects", cmd_pack_objects, RUN_SETUP },
328 { "peek-remote", cmd_ls_remote },
329 { "pickaxe", cmd_blame, RUN_SETUP },
330 { "prune", cmd_prune, RUN_SETUP },
331 { "prune-packed", cmd_prune_packed, RUN_SETUP },
332 { "push", cmd_push, RUN_SETUP },
333 { "read-tree", cmd_read_tree, RUN_SETUP },
334 { "receive-pack", cmd_receive_pack },
335 { "reflog", cmd_reflog, RUN_SETUP },
336 { "remote", cmd_remote, RUN_SETUP },
337 { "repo-config", cmd_config },
338 { "rerere", cmd_rerere, RUN_SETUP },
339 { "reset", cmd_reset, RUN_SETUP },
340 { "rev-list", cmd_rev_list, RUN_SETUP },
341 { "rev-parse", cmd_rev_parse },
342 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
343 { "rm", cmd_rm, RUN_SETUP },
344 { "send-pack", cmd_send_pack, RUN_SETUP },
345 { "shortlog", cmd_shortlog, USE_PAGER },
346 { "show-branch", cmd_show_branch, RUN_SETUP },
347 { "show", cmd_show, RUN_SETUP | USE_PAGER },
348 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
349 { "stripspace", cmd_stripspace },
350 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
351 { "tag", cmd_tag, RUN_SETUP },
352 { "tar-tree", cmd_tar_tree },
353 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
354 { "update-index", cmd_update_index, RUN_SETUP },
355 { "update-ref", cmd_update_ref, RUN_SETUP },
356 { "upload-archive", cmd_upload_archive },
357 { "verify-tag", cmd_verify_tag, RUN_SETUP },
358 { "version", cmd_version },
359 { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
360 { "write-tree", cmd_write_tree, RUN_SETUP },
361 { "verify-pack", cmd_verify_pack },
362 { "show-ref", cmd_show_ref, RUN_SETUP },
363 { "pack-refs", cmd_pack_refs, RUN_SETUP },
364 };
365 int i;
366 static const char ext[] = STRIP_EXTENSION;
367
368 if (sizeof(ext) > 1) {
369 i = strlen(argv[0]) - strlen(ext);
370 if (i > 0 && !strcmp(argv[0] + i, ext)) {
371 char *argv0 = xstrdup(argv[0]);
372 argv[0] = cmd = argv0;
373 argv0[i] = '\0';
374 }
375 }
376
377 /* Turn "git cmd --help" into "git help cmd" */
378 if (argc > 1 && !strcmp(argv[1], "--help")) {
379 argv[1] = argv[0];
380 argv[0] = cmd = "help";
381 }
382
383 for (i = 0; i < ARRAY_SIZE(commands); i++) {
384 struct cmd_struct *p = commands+i;
385 if (strcmp(p->cmd, cmd))
386 continue;
387 exit(run_command(p, argc, argv));
388 }
389 }
390
391 static void execv_dashed_external(const char **argv)
392 {
393 struct strbuf cmd = STRBUF_INIT;
394 const char *tmp;
395
396 strbuf_addf(&cmd, "git-%s", argv[0]);
397
398 /*
399 * argv[0] must be the git command, but the argv array
400 * belongs to the caller, and may be reused in
401 * subsequent loop iterations. Save argv[0] and
402 * restore it on error.
403 */
404 tmp = argv[0];
405 argv[0] = cmd.buf;
406
407 trace_argv_printf(argv, "trace: exec:");
408
409 /* execvp() can only ever return if it fails */
410 execvp(cmd.buf, (char **)argv);
411
412 trace_printf("trace: exec failed: %s\n", strerror(errno));
413
414 argv[0] = tmp;
415
416 strbuf_release(&cmd);
417 }
418
419 static int run_argv(int *argcp, const char ***argv)
420 {
421 int done_alias = 0;
422
423 while (1) {
424 /* See if it's an internal command */
425 handle_internal_command(*argcp, *argv);
426
427 /* .. then try the external ones */
428 execv_dashed_external(*argv);
429
430 /* It could be an alias -- this works around the insanity
431 * of overriding "git log" with "git show" by having
432 * alias.log = show
433 */
434 if (done_alias || !handle_alias(argcp, argv))
435 break;
436 done_alias = 1;
437 }
438
439 return done_alias;
440 }
441
442
443 int main(int argc, const char **argv)
444 {
445 const char *cmd;
446
447 if (argv[0] && *argv[0])
448 cmd = git_extract_argv0_path(argv[0]);
449 else
450 cmd = "git-help";
451
452 /*
453 * "git-xxxx" is the same as "git xxxx", but we obviously:
454 *
455 * - cannot take flags in between the "git" and the "xxxx".
456 * - cannot execute it externally (since it would just do
457 * the same thing over again)
458 *
459 * So we just directly call the internal command handler, and
460 * die if that one cannot handle it.
461 */
462 if (!prefixcmp(cmd, "git-")) {
463 cmd += 4;
464 argv[0] = cmd;
465 handle_internal_command(argc, argv);
466 die("cannot handle %s internally", cmd);
467 }
468
469 /* Look for flags.. */
470 argv++;
471 argc--;
472 handle_options(&argv, &argc, NULL);
473 commit_pager_choice();
474 if (argc > 0) {
475 if (!prefixcmp(argv[0], "--"))
476 argv[0] += 2;
477 } else {
478 /* The user didn't specify a command; give them help */
479 printf("usage: %s\n\n", git_usage_string);
480 list_common_cmds_help();
481 printf("\n%s\n", git_more_info_string);
482 exit(1);
483 }
484 cmd = argv[0];
485
486 /*
487 * We use PATH to find git commands, but we prepend some higher
488 * precidence paths: the "--exec-path" option, the GIT_EXEC_PATH
489 * environment, and the $(gitexecdir) from the Makefile at build
490 * time.
491 */
492 setup_path();
493
494 while (1) {
495 static int done_help = 0;
496 static int was_alias = 0;
497 was_alias = run_argv(&argc, &argv);
498 if (errno != ENOENT)
499 break;
500 if (was_alias) {
501 fprintf(stderr, "Expansion of alias '%s' failed; "
502 "'%s' is not a git-command\n",
503 cmd, argv[0]);
504 exit(1);
505 }
506 if (!done_help) {
507 cmd = argv[0] = help_unknown_cmd(cmd);
508 done_help = 1;
509 } else
510 break;
511 }
512
513 fprintf(stderr, "Failed to run command '%s': %s\n",
514 cmd, strerror(errno));
515
516 return 1;
517 }