config: Give error message when not changing a multivar
[git] / git.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "exec_cmd.h"
4 #include "help.h"
5 #include "quote.h"
6 #include "run-command.h"
7
8 const char git_usage_string[] =
9         "git [--version] [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
10         "           [-p|--paginate|--no-pager] [--no-replace-objects]\n"
11         "           [--bare] [--git-dir=<path>] [--work-tree=<path>]\n"
12         "           [-c name=value] [--help]\n"
13         "           <command> [<args>]";
14
15 const char git_more_info_string[] =
16         "See 'git help <command>' for more information on a specific command.";
17
18 static struct startup_info git_startup_info;
19 static int use_pager = -1;
20 struct pager_config {
21         const char *cmd;
22         int want;
23         char *value;
24 };
25
26 static int pager_command_config(const char *var, const char *value, void *data)
27 {
28         struct pager_config *c = data;
29         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd)) {
30                 int b = git_config_maybe_bool(var, value);
31                 if (b >= 0)
32                         c->want = b;
33                 else {
34                         c->want = 1;
35                         c->value = xstrdup(value);
36                 }
37         }
38         return 0;
39 }
40
41 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
42 int check_pager_config(const char *cmd)
43 {
44         struct pager_config c;
45         c.cmd = cmd;
46         c.want = -1;
47         c.value = NULL;
48         git_config(pager_command_config, &c);
49         if (c.value)
50                 pager_program = c.value;
51         return c.want;
52 }
53
54 static void commit_pager_choice(void) {
55         switch (use_pager) {
56         case 0:
57                 setenv("GIT_PAGER", "cat", 1);
58                 break;
59         case 1:
60                 setup_pager();
61                 break;
62         default:
63                 break;
64         }
65 }
66
67 static int handle_options(const char ***argv, int *argc, int *envchanged)
68 {
69         int handled = 0;
70
71         while (*argc > 0) {
72                 const char *cmd = (*argv)[0];
73                 if (cmd[0] != '-')
74                         break;
75
76                 /*
77                  * For legacy reasons, the "version" and "help"
78                  * commands can be written with "--" prepended
79                  * to make them look like flags.
80                  */
81                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
82                         break;
83
84                 /*
85                  * Check remaining flags.
86                  */
87                 if (!prefixcmp(cmd, "--exec-path")) {
88                         cmd += 11;
89                         if (*cmd == '=')
90                                 git_set_argv_exec_path(cmd + 1);
91                         else {
92                                 puts(git_exec_path());
93                                 exit(0);
94                         }
95                 } else if (!strcmp(cmd, "--html-path")) {
96                         puts(system_path(GIT_HTML_PATH));
97                         exit(0);
98                 } else if (!strcmp(cmd, "--man-path")) {
99                         puts(system_path(GIT_MAN_PATH));
100                         exit(0);
101                 } else if (!strcmp(cmd, "--info-path")) {
102                         puts(system_path(GIT_INFO_PATH));
103                         exit(0);
104                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
105                         use_pager = 1;
106                 } else if (!strcmp(cmd, "--no-pager")) {
107                         use_pager = 0;
108                         if (envchanged)
109                                 *envchanged = 1;
110                 } else if (!strcmp(cmd, "--no-replace-objects")) {
111                         read_replace_refs = 0;
112                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
113                         if (envchanged)
114                                 *envchanged = 1;
115                 } else if (!strcmp(cmd, "--git-dir")) {
116                         if (*argc < 2) {
117                                 fprintf(stderr, "No directory given for --git-dir.\n" );
118                                 usage(git_usage_string);
119                         }
120                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
121                         if (envchanged)
122                                 *envchanged = 1;
123                         (*argv)++;
124                         (*argc)--;
125                         handled++;
126                 } else if (!prefixcmp(cmd, "--git-dir=")) {
127                         setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
128                         if (envchanged)
129                                 *envchanged = 1;
130                 } else if (!strcmp(cmd, "--work-tree")) {
131                         if (*argc < 2) {
132                                 fprintf(stderr, "No directory given for --work-tree.\n" );
133                                 usage(git_usage_string);
134                         }
135                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
136                         if (envchanged)
137                                 *envchanged = 1;
138                         (*argv)++;
139                         (*argc)--;
140                 } else if (!prefixcmp(cmd, "--work-tree=")) {
141                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
142                         if (envchanged)
143                                 *envchanged = 1;
144                 } else if (!strcmp(cmd, "--bare")) {
145                         static char git_dir[PATH_MAX+1];
146                         is_bare_repository_cfg = 1;
147                         setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
148                         if (envchanged)
149                                 *envchanged = 1;
150                 } else if (!strcmp(cmd, "-c")) {
151                         if (*argc < 2) {
152                                 fprintf(stderr, "-c expects a configuration string\n" );
153                                 usage(git_usage_string);
154                         }
155                         git_config_push_parameter((*argv)[1]);
156                         (*argv)++;
157                         (*argc)--;
158                 } else {
159                         fprintf(stderr, "Unknown option: %s\n", cmd);
160                         usage(git_usage_string);
161                 }
162
163                 (*argv)++;
164                 (*argc)--;
165                 handled++;
166         }
167         return handled;
168 }
169
170 static int handle_alias(int *argcp, const char ***argv)
171 {
172         int envchanged = 0, ret = 0, saved_errno = errno;
173         const char *subdir;
174         int count, option_count;
175         const char **new_argv;
176         const char *alias_command;
177         char *alias_string;
178         int unused_nongit;
179
180         subdir = setup_git_directory_gently(&unused_nongit);
181
182         alias_command = (*argv)[0];
183         alias_string = alias_lookup(alias_command);
184         if (alias_string) {
185                 if (alias_string[0] == '!') {
186                         const char **alias_argv;
187                         int argc = *argcp, i;
188                         struct strbuf sb = STRBUF_INIT;
189                         const char *env[2];
190
191                         commit_pager_choice();
192
193                         /* build alias_argv */
194                         alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
195                         alias_argv[0] = alias_string + 1;
196                         for (i = 1; i < argc; ++i)
197                                 alias_argv[i] = (*argv)[i];
198                         alias_argv[argc] = NULL;
199
200                         strbuf_addstr(&sb, "GIT_PREFIX=");
201                         if (subdir)
202                                 strbuf_addstr(&sb, subdir);
203                         env[0] = sb.buf;
204                         env[1] = NULL;
205                         ret = run_command_v_opt_cd_env(alias_argv, RUN_USING_SHELL, NULL, env);
206                         strbuf_release(&sb);
207                         if (ret >= 0)   /* normal exit */
208                                 exit(ret);
209
210                         die_errno("While expanding alias '%s': '%s'",
211                             alias_command, alias_string + 1);
212                 }
213                 count = split_cmdline(alias_string, &new_argv);
214                 if (count < 0)
215                         die("Bad alias.%s string: %s", alias_command,
216                             split_cmdline_strerror(count));
217                 option_count = handle_options(&new_argv, &count, &envchanged);
218                 if (envchanged)
219                         die("alias '%s' changes environment variables\n"
220                                  "You can use '!git' in the alias to do this.",
221                                  alias_command);
222                 memmove(new_argv - option_count, new_argv,
223                                 count * sizeof(char *));
224                 new_argv -= option_count;
225
226                 if (count < 1)
227                         die("empty alias for %s", alias_command);
228
229                 if (!strcmp(alias_command, new_argv[0]))
230                         die("recursive alias: %s", alias_command);
231
232                 trace_argv_printf(new_argv,
233                                   "trace: alias expansion: %s =>",
234                                   alias_command);
235
236                 new_argv = xrealloc(new_argv, sizeof(char *) *
237                                     (count + *argcp));
238                 /* insert after command name */
239                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
240
241                 *argv = new_argv;
242                 *argcp += count - 1;
243
244                 ret = 1;
245         }
246
247         if (subdir && chdir(subdir))
248                 die_errno("Cannot change to '%s'", subdir);
249
250         errno = saved_errno;
251
252         return ret;
253 }
254
255 const char git_version_string[] = GIT_VERSION;
256
257 #define RUN_SETUP               (1<<0)
258 #define RUN_SETUP_GENTLY        (1<<1)
259 #define USE_PAGER               (1<<2)
260 /*
261  * require working tree to be present -- anything uses this needs
262  * RUN_SETUP for reading from the configuration file.
263  */
264 #define NEED_WORK_TREE          (1<<3)
265
266 struct cmd_struct {
267         const char *cmd;
268         int (*fn)(int, const char **, const char *);
269         int option;
270 };
271
272 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
273 {
274         int status, help;
275         struct stat st;
276         const char *prefix;
277
278         prefix = NULL;
279         help = argc == 2 && !strcmp(argv[1], "-h");
280         if (!help) {
281                 if (p->option & RUN_SETUP)
282                         prefix = setup_git_directory();
283                 if (p->option & RUN_SETUP_GENTLY) {
284                         int nongit_ok;
285                         prefix = setup_git_directory_gently(&nongit_ok);
286                 }
287
288                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
289                         use_pager = check_pager_config(p->cmd);
290                 if (use_pager == -1 && p->option & USE_PAGER)
291                         use_pager = 1;
292
293                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
294                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
295                         trace_repo_setup(prefix);
296         }
297         commit_pager_choice();
298
299         if (!help && p->option & NEED_WORK_TREE)
300                 setup_work_tree();
301
302         trace_argv_printf(argv, "trace: built-in: git");
303
304         status = p->fn(argc, argv, prefix);
305         if (status)
306                 return status;
307
308         /* Somebody closed stdout? */
309         if (fstat(fileno(stdout), &st))
310                 return 0;
311         /* Ignore write errors for pipes and sockets.. */
312         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
313                 return 0;
314
315         /* Check for ENOSPC and EIO errors.. */
316         if (fflush(stdout))
317                 die_errno("write failure on standard output");
318         if (ferror(stdout))
319                 die("unknown write failure on standard output");
320         if (fclose(stdout))
321                 die_errno("close failed on standard output");
322         return 0;
323 }
324
325 static void handle_internal_command(int argc, const char **argv)
326 {
327         const char *cmd = argv[0];
328         static struct cmd_struct commands[] = {
329                 { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
330                 { "annotate", cmd_annotate, RUN_SETUP },
331                 { "apply", cmd_apply, RUN_SETUP_GENTLY },
332                 { "archive", cmd_archive },
333                 { "bisect--helper", cmd_bisect__helper, RUN_SETUP | NEED_WORK_TREE },
334                 { "blame", cmd_blame, RUN_SETUP },
335                 { "branch", cmd_branch, RUN_SETUP },
336                 { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
337                 { "cat-file", cmd_cat_file, RUN_SETUP },
338                 { "check-attr", cmd_check_attr, RUN_SETUP },
339                 { "check-ref-format", cmd_check_ref_format },
340                 { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
341                 { "checkout-index", cmd_checkout_index,
342                         RUN_SETUP | NEED_WORK_TREE},
343                 { "cherry", cmd_cherry, RUN_SETUP },
344                 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
345                 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
346                 { "clone", cmd_clone },
347                 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
348                 { "commit-tree", cmd_commit_tree, RUN_SETUP },
349                 { "config", cmd_config, RUN_SETUP_GENTLY },
350                 { "count-objects", cmd_count_objects, RUN_SETUP },
351                 { "describe", cmd_describe, RUN_SETUP },
352                 { "diff", cmd_diff },
353                 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
354                 { "diff-index", cmd_diff_index, RUN_SETUP },
355                 { "diff-tree", cmd_diff_tree, RUN_SETUP },
356                 { "fast-export", cmd_fast_export, RUN_SETUP },
357                 { "fetch", cmd_fetch, RUN_SETUP },
358                 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
359                 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
360                 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
361                 { "format-patch", cmd_format_patch, RUN_SETUP },
362                 { "fsck", cmd_fsck, RUN_SETUP },
363                 { "fsck-objects", cmd_fsck, RUN_SETUP },
364                 { "gc", cmd_gc, RUN_SETUP },
365                 { "get-tar-commit-id", cmd_get_tar_commit_id },
366                 { "grep", cmd_grep, RUN_SETUP_GENTLY },
367                 { "hash-object", cmd_hash_object },
368                 { "help", cmd_help },
369                 { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
370                 { "init", cmd_init_db },
371                 { "init-db", cmd_init_db },
372                 { "log", cmd_log, RUN_SETUP },
373                 { "ls-files", cmd_ls_files, RUN_SETUP },
374                 { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
375                 { "ls-tree", cmd_ls_tree, RUN_SETUP },
376                 { "mailinfo", cmd_mailinfo },
377                 { "mailsplit", cmd_mailsplit },
378                 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
379                 { "merge-base", cmd_merge_base, RUN_SETUP },
380                 { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
381                 { "merge-index", cmd_merge_index, RUN_SETUP },
382                 { "merge-ours", cmd_merge_ours, RUN_SETUP },
383                 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
384                 { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
385                 { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
386                 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
387                 { "merge-tree", cmd_merge_tree, RUN_SETUP },
388                 { "mktag", cmd_mktag, RUN_SETUP },
389                 { "mktree", cmd_mktree, RUN_SETUP },
390                 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
391                 { "name-rev", cmd_name_rev, RUN_SETUP },
392                 { "notes", cmd_notes, RUN_SETUP },
393                 { "pack-objects", cmd_pack_objects, RUN_SETUP },
394                 { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
395                 { "pack-refs", cmd_pack_refs, RUN_SETUP },
396                 { "patch-id", cmd_patch_id },
397                 { "peek-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
398                 { "pickaxe", cmd_blame, RUN_SETUP },
399                 { "prune", cmd_prune, RUN_SETUP },
400                 { "prune-packed", cmd_prune_packed, RUN_SETUP },
401                 { "push", cmd_push, RUN_SETUP },
402                 { "read-tree", cmd_read_tree, RUN_SETUP },
403                 { "receive-pack", cmd_receive_pack },
404                 { "reflog", cmd_reflog, RUN_SETUP },
405                 { "remote", cmd_remote, RUN_SETUP },
406                 { "remote-ext", cmd_remote_ext },
407                 { "remote-fd", cmd_remote_fd },
408                 { "replace", cmd_replace, RUN_SETUP },
409                 { "repo-config", cmd_repo_config, RUN_SETUP_GENTLY },
410                 { "rerere", cmd_rerere, RUN_SETUP },
411                 { "reset", cmd_reset, RUN_SETUP },
412                 { "rev-list", cmd_rev_list, RUN_SETUP },
413                 { "rev-parse", cmd_rev_parse },
414                 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
415                 { "rm", cmd_rm, RUN_SETUP },
416                 { "send-pack", cmd_send_pack, RUN_SETUP },
417                 { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
418                 { "show", cmd_show, RUN_SETUP },
419                 { "show-branch", cmd_show_branch, RUN_SETUP },
420                 { "show-ref", cmd_show_ref, RUN_SETUP },
421                 { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
422                 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
423                 { "stripspace", cmd_stripspace },
424                 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
425                 { "tag", cmd_tag, RUN_SETUP },
426                 { "tar-tree", cmd_tar_tree },
427                 { "unpack-file", cmd_unpack_file, RUN_SETUP },
428                 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
429                 { "update-index", cmd_update_index, RUN_SETUP },
430                 { "update-ref", cmd_update_ref, RUN_SETUP },
431                 { "update-server-info", cmd_update_server_info, RUN_SETUP },
432                 { "upload-archive", cmd_upload_archive },
433                 { "var", cmd_var, RUN_SETUP_GENTLY },
434                 { "verify-pack", cmd_verify_pack },
435                 { "verify-tag", cmd_verify_tag, RUN_SETUP },
436                 { "version", cmd_version },
437                 { "whatchanged", cmd_whatchanged, RUN_SETUP },
438                 { "write-tree", cmd_write_tree, RUN_SETUP },
439         };
440         int i;
441         static const char ext[] = STRIP_EXTENSION;
442
443         if (sizeof(ext) > 1) {
444                 i = strlen(argv[0]) - strlen(ext);
445                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
446                         char *argv0 = xstrdup(argv[0]);
447                         argv[0] = cmd = argv0;
448                         argv0[i] = '\0';
449                 }
450         }
451
452         /* Turn "git cmd --help" into "git help cmd" */
453         if (argc > 1 && !strcmp(argv[1], "--help")) {
454                 argv[1] = argv[0];
455                 argv[0] = cmd = "help";
456         }
457
458         for (i = 0; i < ARRAY_SIZE(commands); i++) {
459                 struct cmd_struct *p = commands+i;
460                 if (strcmp(p->cmd, cmd))
461                         continue;
462                 exit(run_builtin(p, argc, argv));
463         }
464 }
465
466 static void execv_dashed_external(const char **argv)
467 {
468         struct strbuf cmd = STRBUF_INIT;
469         const char *tmp;
470         int status;
471
472         commit_pager_choice();
473
474         strbuf_addf(&cmd, "git-%s", argv[0]);
475
476         /*
477          * argv[0] must be the git command, but the argv array
478          * belongs to the caller, and may be reused in
479          * subsequent loop iterations. Save argv[0] and
480          * restore it on error.
481          */
482         tmp = argv[0];
483         argv[0] = cmd.buf;
484
485         trace_argv_printf(argv, "trace: exec:");
486
487         /*
488          * if we fail because the command is not found, it is
489          * OK to return. Otherwise, we just pass along the status code.
490          */
491         status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE);
492         if (status >= 0 || errno != ENOENT)
493                 exit(status);
494
495         argv[0] = tmp;
496
497         strbuf_release(&cmd);
498 }
499
500 static int run_argv(int *argcp, const char ***argv)
501 {
502         int done_alias = 0;
503
504         while (1) {
505                 /* See if it's an internal command */
506                 handle_internal_command(*argcp, *argv);
507
508                 /* .. then try the external ones */
509                 execv_dashed_external(*argv);
510
511                 /* It could be an alias -- this works around the insanity
512                  * of overriding "git log" with "git show" by having
513                  * alias.log = show
514                  */
515                 if (done_alias || !handle_alias(argcp, argv))
516                         break;
517                 done_alias = 1;
518         }
519
520         return done_alias;
521 }
522
523
524 int main(int argc, const char **argv)
525 {
526         const char *cmd;
527
528         startup_info = &git_startup_info;
529
530         cmd = git_extract_argv0_path(argv[0]);
531         if (!cmd)
532                 cmd = "git-help";
533
534         /*
535          * "git-xxxx" is the same as "git xxxx", but we obviously:
536          *
537          *  - cannot take flags in between the "git" and the "xxxx".
538          *  - cannot execute it externally (since it would just do
539          *    the same thing over again)
540          *
541          * So we just directly call the internal command handler, and
542          * die if that one cannot handle it.
543          */
544         if (!prefixcmp(cmd, "git-")) {
545                 cmd += 4;
546                 argv[0] = cmd;
547                 handle_internal_command(argc, argv);
548                 die("cannot handle %s internally", cmd);
549         }
550
551         /* Look for flags.. */
552         argv++;
553         argc--;
554         handle_options(&argv, &argc, NULL);
555         if (argc > 0) {
556                 if (!prefixcmp(argv[0], "--"))
557                         argv[0] += 2;
558         } else {
559                 /* The user didn't specify a command; give them help */
560                 commit_pager_choice();
561                 printf("usage: %s\n\n", git_usage_string);
562                 list_common_cmds_help();
563                 printf("\n%s\n", git_more_info_string);
564                 exit(1);
565         }
566         cmd = argv[0];
567
568         /*
569          * We use PATH to find git commands, but we prepend some higher
570          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
571          * environment, and the $(gitexecdir) from the Makefile at build
572          * time.
573          */
574         setup_path();
575
576         while (1) {
577                 static int done_help = 0;
578                 static int was_alias = 0;
579                 was_alias = run_argv(&argc, &argv);
580                 if (errno != ENOENT)
581                         break;
582                 if (was_alias) {
583                         fprintf(stderr, "Expansion of alias '%s' failed; "
584                                 "'%s' is not a git command\n",
585                                 cmd, argv[0]);
586                         exit(1);
587                 }
588                 if (!done_help) {
589                         cmd = argv[0] = help_unknown_cmd(cmd);
590                         done_help = 1;
591                 } else
592                         break;
593         }
594
595         fprintf(stderr, "Failed to run command '%s': %s\n",
596                 cmd, strerror(errno));
597
598         return 1;
599 }