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