Merge branch 'rs/blame'
[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'\n",
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)
199                 chdir(subdir);
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                 { "annotate", cmd_annotate, RUN_SETUP },
270                 { "apply", cmd_apply },
271                 { "archive", cmd_archive },
272                 { "blame", cmd_blame, RUN_SETUP },
273                 { "branch", cmd_branch, RUN_SETUP },
274                 { "bundle", cmd_bundle },
275                 { "cat-file", cmd_cat_file, RUN_SETUP },
276                 { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
277                 { "checkout-index", cmd_checkout_index,
278                         RUN_SETUP | NEED_WORK_TREE},
279                 { "check-ref-format", cmd_check_ref_format },
280                 { "check-attr", cmd_check_attr, RUN_SETUP },
281                 { "cherry", cmd_cherry, RUN_SETUP },
282                 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
283                 { "clone", cmd_clone },
284                 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
285                 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
286                 { "commit-tree", cmd_commit_tree, RUN_SETUP },
287                 { "config", cmd_config },
288                 { "count-objects", cmd_count_objects, RUN_SETUP },
289                 { "describe", cmd_describe, RUN_SETUP },
290                 { "diff", cmd_diff },
291                 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
292                 { "diff-index", cmd_diff_index, RUN_SETUP },
293                 { "diff-tree", cmd_diff_tree, RUN_SETUP },
294                 { "fast-export", cmd_fast_export, RUN_SETUP },
295                 { "fetch", cmd_fetch, RUN_SETUP },
296                 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
297                 { "fetch--tool", cmd_fetch__tool, RUN_SETUP },
298                 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
299                 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
300                 { "format-patch", cmd_format_patch, RUN_SETUP },
301                 { "fsck", cmd_fsck, RUN_SETUP },
302                 { "fsck-objects", cmd_fsck, RUN_SETUP },
303                 { "gc", cmd_gc, RUN_SETUP },
304                 { "get-tar-commit-id", cmd_get_tar_commit_id },
305                 { "grep", cmd_grep, RUN_SETUP | USE_PAGER },
306                 { "help", cmd_help },
307 #ifndef NO_CURL
308                 { "http-fetch", cmd_http_fetch, RUN_SETUP },
309 #endif
310                 { "init", cmd_init_db },
311                 { "init-db", cmd_init_db },
312                 { "log", cmd_log, RUN_SETUP | USE_PAGER },
313                 { "ls-files", cmd_ls_files, RUN_SETUP },
314                 { "ls-tree", cmd_ls_tree, RUN_SETUP },
315                 { "ls-remote", cmd_ls_remote },
316                 { "mailinfo", cmd_mailinfo },
317                 { "mailsplit", cmd_mailsplit },
318                 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
319                 { "merge-base", cmd_merge_base, RUN_SETUP },
320                 { "merge-file", cmd_merge_file },
321                 { "merge-ours", cmd_merge_ours, RUN_SETUP },
322                 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
323                 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
324                 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
325                 { "name-rev", cmd_name_rev, RUN_SETUP },
326                 { "pack-objects", cmd_pack_objects, RUN_SETUP },
327                 { "peek-remote", cmd_ls_remote },
328                 { "pickaxe", cmd_blame, RUN_SETUP },
329                 { "prune", cmd_prune, RUN_SETUP },
330                 { "prune-packed", cmd_prune_packed, RUN_SETUP },
331                 { "push", cmd_push, RUN_SETUP },
332                 { "read-tree", cmd_read_tree, RUN_SETUP },
333                 { "receive-pack", cmd_receive_pack },
334                 { "reflog", cmd_reflog, RUN_SETUP },
335                 { "remote", cmd_remote, RUN_SETUP },
336                 { "repo-config", cmd_config },
337                 { "rerere", cmd_rerere, RUN_SETUP },
338                 { "reset", cmd_reset, RUN_SETUP },
339                 { "rev-list", cmd_rev_list, RUN_SETUP },
340                 { "rev-parse", cmd_rev_parse },
341                 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
342                 { "rm", cmd_rm, RUN_SETUP },
343                 { "send-pack", cmd_send_pack, RUN_SETUP },
344                 { "shortlog", cmd_shortlog, USE_PAGER },
345                 { "show-branch", cmd_show_branch, RUN_SETUP },
346                 { "show", cmd_show, RUN_SETUP | USE_PAGER },
347                 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
348                 { "stripspace", cmd_stripspace },
349                 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
350                 { "tag", cmd_tag, RUN_SETUP },
351                 { "tar-tree", cmd_tar_tree },
352                 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
353                 { "update-index", cmd_update_index, RUN_SETUP },
354                 { "update-ref", cmd_update_ref, RUN_SETUP },
355                 { "upload-archive", cmd_upload_archive },
356                 { "verify-tag", cmd_verify_tag, RUN_SETUP },
357                 { "version", cmd_version },
358                 { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
359                 { "write-tree", cmd_write_tree, RUN_SETUP },
360                 { "verify-pack", cmd_verify_pack },
361                 { "show-ref", cmd_show_ref, RUN_SETUP },
362                 { "pack-refs", cmd_pack_refs, RUN_SETUP },
363         };
364         int i;
365         static const char ext[] = STRIP_EXTENSION;
366
367         if (sizeof(ext) > 1) {
368                 i = strlen(argv[0]) - strlen(ext);
369                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
370                         char *argv0 = xstrdup(argv[0]);
371                         argv[0] = cmd = argv0;
372                         argv0[i] = '\0';
373                 }
374         }
375
376         /* Turn "git cmd --help" into "git help cmd" */
377         if (argc > 1 && !strcmp(argv[1], "--help")) {
378                 argv[1] = argv[0];
379                 argv[0] = cmd = "help";
380         }
381
382         for (i = 0; i < ARRAY_SIZE(commands); i++) {
383                 struct cmd_struct *p = commands+i;
384                 if (strcmp(p->cmd, cmd))
385                         continue;
386                 exit(run_command(p, argc, argv));
387         }
388 }
389
390 static void execv_dashed_external(const char **argv)
391 {
392         struct strbuf cmd = STRBUF_INIT;
393         const char *tmp;
394
395         strbuf_addf(&cmd, "git-%s", argv[0]);
396
397         /*
398          * argv[0] must be the git command, but the argv array
399          * belongs to the caller, and may be reused in
400          * subsequent loop iterations. Save argv[0] and
401          * restore it on error.
402          */
403         tmp = argv[0];
404         argv[0] = cmd.buf;
405
406         trace_argv_printf(argv, "trace: exec:");
407
408         /* execvp() can only ever return if it fails */
409         execvp(cmd.buf, (char **)argv);
410
411         trace_printf("trace: exec failed: %s\n", strerror(errno));
412
413         argv[0] = tmp;
414
415         strbuf_release(&cmd);
416 }
417
418
419 int main(int argc, const char **argv)
420 {
421         const char *cmd = argv[0] && *argv[0] ? argv[0] : "git-help";
422         char *slash = (char *)cmd + strlen(cmd);
423         int done_alias = 0;
424
425         /*
426          * Take the basename of argv[0] as the command
427          * name, and the dirname as the default exec_path
428          * if we don't have anything better.
429          */
430         do
431                 --slash;
432         while (cmd <= slash && !is_dir_sep(*slash));
433         if (cmd <= slash) {
434                 *slash++ = 0;
435                 git_set_argv0_path(cmd);
436                 cmd = slash;
437         }
438
439         /*
440          * "git-xxxx" is the same as "git xxxx", but we obviously:
441          *
442          *  - cannot take flags in between the "git" and the "xxxx".
443          *  - cannot execute it externally (since it would just do
444          *    the same thing over again)
445          *
446          * So we just directly call the internal command handler, and
447          * die if that one cannot handle it.
448          */
449         if (!prefixcmp(cmd, "git-")) {
450                 cmd += 4;
451                 argv[0] = cmd;
452                 handle_internal_command(argc, argv);
453                 die("cannot handle %s internally", cmd);
454         }
455
456         /* Look for flags.. */
457         argv++;
458         argc--;
459         handle_options(&argv, &argc, NULL);
460         commit_pager_choice();
461         if (argc > 0) {
462                 if (!prefixcmp(argv[0], "--"))
463                         argv[0] += 2;
464         } else {
465                 /* The user didn't specify a command; give them help */
466                 printf("usage: %s\n\n", git_usage_string);
467                 list_common_cmds_help();
468                 printf("\n%s\n", git_more_info_string);
469                 exit(1);
470         }
471         cmd = argv[0];
472
473         /*
474          * We use PATH to find git commands, but we prepend some higher
475          * precidence paths: the "--exec-path" option, the GIT_EXEC_PATH
476          * environment, and the $(gitexecdir) from the Makefile at build
477          * time.
478          */
479         setup_path();
480
481         while (1) {
482                 /* See if it's an internal command */
483                 handle_internal_command(argc, argv);
484
485                 /* .. then try the external ones */
486                 execv_dashed_external(argv);
487
488                 /* It could be an alias -- this works around the insanity
489                  * of overriding "git log" with "git show" by having
490                  * alias.log = show
491                  */
492                 if (done_alias || !handle_alias(&argc, &argv))
493                         break;
494                 done_alias = 1;
495         }
496
497         if (errno == ENOENT) {
498                 if (done_alias) {
499                         fprintf(stderr, "Expansion of alias '%s' failed; "
500                                 "'%s' is not a git-command\n",
501                                 cmd, argv[0]);
502                         exit(1);
503                 }
504                 argv[0] = help_unknown_cmd(cmd);
505                 handle_internal_command(argc, argv);
506                 execv_dashed_external(argv);
507         }
508
509         fprintf(stderr, "Failed to run command '%s': %s\n",
510                 cmd, strerror(errno));
511
512         return 1;
513 }