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