Merge branch 'ns/am-to-empty'
[git] / builtin-rev-parse.c
1 /*
2  * rev-parse.c
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  */
6 #include "cache.h"
7 #include "commit.h"
8 #include "refs.h"
9 #include "quote.h"
10 #include "builtin.h"
11 #include "parse-options.h"
12
13 #define DO_REVS         1
14 #define DO_NOREV        2
15 #define DO_FLAGS        4
16 #define DO_NONFLAGS     8
17 static int filter = ~0;
18
19 static const char *def;
20
21 #define NORMAL 0
22 #define REVERSED 1
23 static int show_type = NORMAL;
24
25 #define SHOW_SYMBOLIC_ASIS 1
26 #define SHOW_SYMBOLIC_FULL 2
27 static int symbolic;
28 static int abbrev;
29 static int abbrev_ref;
30 static int abbrev_ref_strict;
31 static int output_sq;
32
33 /*
34  * Some arguments are relevant "revision" arguments,
35  * others are about output format or other details.
36  * This sorts it all out.
37  */
38 static int is_rev_argument(const char *arg)
39 {
40         static const char *rev_args[] = {
41                 "--all",
42                 "--bisect",
43                 "--dense",
44                 "--branches",
45                 "--header",
46                 "--max-age=",
47                 "--max-count=",
48                 "--min-age=",
49                 "--no-merges",
50                 "--objects",
51                 "--objects-edge",
52                 "--parents",
53                 "--pretty",
54                 "--remotes",
55                 "--sparse",
56                 "--tags",
57                 "--topo-order",
58                 "--date-order",
59                 "--unpacked",
60                 NULL
61         };
62         const char **p = rev_args;
63
64         /* accept -<digit>, like traditional "head" */
65         if ((*arg == '-') && isdigit(arg[1]))
66                 return 1;
67
68         for (;;) {
69                 const char *str = *p++;
70                 int len;
71                 if (!str)
72                         return 0;
73                 len = strlen(str);
74                 if (!strcmp(arg, str) ||
75                     (str[len-1] == '=' && !strncmp(arg, str, len)))
76                         return 1;
77         }
78 }
79
80 /* Output argument as a string, either SQ or normal */
81 static void show(const char *arg)
82 {
83         if (output_sq) {
84                 int sq = '\'', ch;
85
86                 putchar(sq);
87                 while ((ch = *arg++)) {
88                         if (ch == sq)
89                                 fputs("'\\'", stdout);
90                         putchar(ch);
91                 }
92                 putchar(sq);
93                 putchar(' ');
94         }
95         else
96                 puts(arg);
97 }
98
99 /* Like show(), but with a negation prefix according to type */
100 static void show_with_type(int type, const char *arg)
101 {
102         if (type != show_type)
103                 putchar('^');
104         show(arg);
105 }
106
107 /* Output a revision, only if filter allows it */
108 static void show_rev(int type, const unsigned char *sha1, const char *name)
109 {
110         if (!(filter & DO_REVS))
111                 return;
112         def = NULL;
113
114         if ((symbolic || abbrev_ref) && name) {
115                 if (symbolic == SHOW_SYMBOLIC_FULL || abbrev_ref) {
116                         unsigned char discard[20];
117                         char *full;
118
119                         switch (dwim_ref(name, strlen(name), discard, &full)) {
120                         case 0:
121                                 /*
122                                  * Not found -- not a ref.  We could
123                                  * emit "name" here, but symbolic-full
124                                  * users are interested in finding the
125                                  * refs spelled in full, and they would
126                                  * need to filter non-refs if we did so.
127                                  */
128                                 break;
129                         case 1: /* happy */
130                                 if (abbrev_ref)
131                                         full = shorten_unambiguous_ref(full,
132                                                 abbrev_ref_strict);
133                                 show_with_type(type, full);
134                                 break;
135                         default: /* ambiguous */
136                                 error("refname '%s' is ambiguous", name);
137                                 break;
138                         }
139                 } else {
140                         show_with_type(type, name);
141                 }
142         }
143         else if (abbrev)
144                 show_with_type(type, find_unique_abbrev(sha1, abbrev));
145         else
146                 show_with_type(type, sha1_to_hex(sha1));
147 }
148
149 /* Output a flag, only if filter allows it. */
150 static int show_flag(const char *arg)
151 {
152         if (!(filter & DO_FLAGS))
153                 return 0;
154         if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
155                 show(arg);
156                 return 1;
157         }
158         return 0;
159 }
160
161 static int show_default(void)
162 {
163         const char *s = def;
164
165         if (s) {
166                 unsigned char sha1[20];
167
168                 def = NULL;
169                 if (!get_sha1(s, sha1)) {
170                         show_rev(NORMAL, sha1, s);
171                         return 1;
172                 }
173         }
174         return 0;
175 }
176
177 static int show_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
178 {
179         show_rev(NORMAL, sha1, refname);
180         return 0;
181 }
182
183 static void show_datestring(const char *flag, const char *datestr)
184 {
185         static char buffer[100];
186
187         /* date handling requires both flags and revs */
188         if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
189                 return;
190         snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
191         show(buffer);
192 }
193
194 static int show_file(const char *arg)
195 {
196         show_default();
197         if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
198                 show(arg);
199                 return 1;
200         }
201         return 0;
202 }
203
204 static int try_difference(const char *arg)
205 {
206         char *dotdot;
207         unsigned char sha1[20];
208         unsigned char end[20];
209         const char *next;
210         const char *this;
211         int symmetric;
212
213         if (!(dotdot = strstr(arg, "..")))
214                 return 0;
215         next = dotdot + 2;
216         this = arg;
217         symmetric = (*next == '.');
218
219         *dotdot = 0;
220         next += symmetric;
221
222         if (!*next)
223                 next = "HEAD";
224         if (dotdot == arg)
225                 this = "HEAD";
226         if (!get_sha1(this, sha1) && !get_sha1(next, end)) {
227                 show_rev(NORMAL, end, next);
228                 show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
229                 if (symmetric) {
230                         struct commit_list *exclude;
231                         struct commit *a, *b;
232                         a = lookup_commit_reference(sha1);
233                         b = lookup_commit_reference(end);
234                         exclude = get_merge_bases(a, b, 1);
235                         while (exclude) {
236                                 struct commit_list *n = exclude->next;
237                                 show_rev(REVERSED,
238                                          exclude->item->object.sha1,NULL);
239                                 free(exclude);
240                                 exclude = n;
241                         }
242                 }
243                 return 1;
244         }
245         *dotdot = '.';
246         return 0;
247 }
248
249 static int try_parent_shorthands(const char *arg)
250 {
251         char *dotdot;
252         unsigned char sha1[20];
253         struct commit *commit;
254         struct commit_list *parents;
255         int parents_only;
256
257         if ((dotdot = strstr(arg, "^!")))
258                 parents_only = 0;
259         else if ((dotdot = strstr(arg, "^@")))
260                 parents_only = 1;
261
262         if (!dotdot || dotdot[2])
263                 return 0;
264
265         *dotdot = 0;
266         if (get_sha1(arg, sha1))
267                 return 0;
268
269         if (!parents_only)
270                 show_rev(NORMAL, sha1, arg);
271         commit = lookup_commit_reference(sha1);
272         for (parents = commit->parents; parents; parents = parents->next)
273                 show_rev(parents_only ? NORMAL : REVERSED,
274                                 parents->item->object.sha1, arg);
275
276         return 1;
277 }
278
279 static int parseopt_dump(const struct option *o, const char *arg, int unset)
280 {
281         struct strbuf *parsed = o->value;
282         if (unset)
283                 strbuf_addf(parsed, " --no-%s", o->long_name);
284         else if (o->short_name)
285                 strbuf_addf(parsed, " -%c", o->short_name);
286         else
287                 strbuf_addf(parsed, " --%s", o->long_name);
288         if (arg) {
289                 strbuf_addch(parsed, ' ');
290                 sq_quote_buf(parsed, arg);
291         }
292         return 0;
293 }
294
295 static const char *skipspaces(const char *s)
296 {
297         while (isspace(*s))
298                 s++;
299         return s;
300 }
301
302 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
303 {
304         static int keep_dashdash = 0;
305         static char const * const parseopt_usage[] = {
306                 "git rev-parse --parseopt [options] -- [<args>...]",
307                 NULL
308         };
309         static struct option parseopt_opts[] = {
310                 OPT_BOOLEAN(0, "keep-dashdash", &keep_dashdash,
311                                         "keep the `--` passed as an arg"),
312                 OPT_END(),
313         };
314
315         struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
316         const char **usage = NULL;
317         struct option *opts = NULL;
318         int onb = 0, osz = 0, unb = 0, usz = 0;
319
320         strbuf_addstr(&parsed, "set --");
321         argc = parse_options(argc, argv, parseopt_opts, parseopt_usage,
322                              PARSE_OPT_KEEP_DASHDASH);
323         if (argc < 1 || strcmp(argv[0], "--"))
324                 usage_with_options(parseopt_usage, parseopt_opts);
325
326         /* get the usage up to the first line with a -- on it */
327         for (;;) {
328                 if (strbuf_getline(&sb, stdin, '\n') == EOF)
329                         die("premature end of input");
330                 ALLOC_GROW(usage, unb + 1, usz);
331                 if (!strcmp("--", sb.buf)) {
332                         if (unb < 1)
333                                 die("no usage string given before the `--' separator");
334                         usage[unb] = NULL;
335                         break;
336                 }
337                 usage[unb++] = strbuf_detach(&sb, NULL);
338         }
339
340         /* parse: (<short>|<short>,<long>|<long>)[=?]? SP+ <help> */
341         while (strbuf_getline(&sb, stdin, '\n') != EOF) {
342                 const char *s;
343                 struct option *o;
344
345                 if (!sb.len)
346                         continue;
347
348                 ALLOC_GROW(opts, onb + 1, osz);
349                 memset(opts + onb, 0, sizeof(opts[onb]));
350
351                 o = &opts[onb++];
352                 s = strchr(sb.buf, ' ');
353                 if (!s || *sb.buf == ' ') {
354                         o->type = OPTION_GROUP;
355                         o->help = xstrdup(skipspaces(sb.buf));
356                         continue;
357                 }
358
359                 o->type = OPTION_CALLBACK;
360                 o->help = xstrdup(skipspaces(s));
361                 o->value = &parsed;
362                 o->flags = PARSE_OPT_NOARG;
363                 o->callback = &parseopt_dump;
364                 while (s > sb.buf && strchr("*=?!", s[-1])) {
365                         switch (*--s) {
366                         case '=':
367                                 o->flags &= ~PARSE_OPT_NOARG;
368                                 break;
369                         case '?':
370                                 o->flags &= ~PARSE_OPT_NOARG;
371                                 o->flags |= PARSE_OPT_OPTARG;
372                                 break;
373                         case '!':
374                                 o->flags |= PARSE_OPT_NONEG;
375                                 break;
376                         case '*':
377                                 o->flags |= PARSE_OPT_HIDDEN;
378                                 break;
379                         }
380                 }
381
382                 if (s - sb.buf == 1) /* short option only */
383                         o->short_name = *sb.buf;
384                 else if (sb.buf[1] != ',') /* long option only */
385                         o->long_name = xmemdupz(sb.buf, s - sb.buf);
386                 else {
387                         o->short_name = *sb.buf;
388                         o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
389                 }
390         }
391         strbuf_release(&sb);
392
393         /* put an OPT_END() */
394         ALLOC_GROW(opts, onb + 1, osz);
395         memset(opts + onb, 0, sizeof(opts[onb]));
396         argc = parse_options(argc, argv, opts, usage,
397                              keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0);
398
399         strbuf_addf(&parsed, " --");
400         sq_quote_argv(&parsed, argv, 0);
401         puts(parsed.buf);
402         return 0;
403 }
404
405 static void die_no_single_rev(int quiet)
406 {
407         if (quiet)
408                 exit(1);
409         else
410                 die("Needed a single revision");
411 }
412
413 int cmd_rev_parse(int argc, const char **argv, const char *prefix)
414 {
415         int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
416         unsigned char sha1[20];
417         const char *name = NULL;
418
419         if (argc > 1 && !strcmp("--parseopt", argv[1]))
420                 return cmd_parseopt(argc - 1, argv + 1, prefix);
421
422         prefix = setup_git_directory();
423         git_config(git_default_config, NULL);
424         for (i = 1; i < argc; i++) {
425                 const char *arg = argv[i];
426
427                 if (as_is) {
428                         if (show_file(arg) && as_is < 2)
429                                 verify_filename(prefix, arg);
430                         continue;
431                 }
432                 if (!strcmp(arg,"-n")) {
433                         if (++i >= argc)
434                                 die("-n requires an argument");
435                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
436                                 show(arg);
437                                 show(argv[i]);
438                         }
439                         continue;
440                 }
441                 if (!prefixcmp(arg, "-n")) {
442                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
443                                 show(arg);
444                         continue;
445                 }
446
447                 if (*arg == '-') {
448                         if (!strcmp(arg, "--")) {
449                                 as_is = 2;
450                                 /* Pass on the "--" if we show anything but files.. */
451                                 if (filter & (DO_FLAGS | DO_REVS))
452                                         show_file(arg);
453                                 continue;
454                         }
455                         if (!strcmp(arg, "--default")) {
456                                 def = argv[i+1];
457                                 i++;
458                                 continue;
459                         }
460                         if (!strcmp(arg, "--revs-only")) {
461                                 filter &= ~DO_NOREV;
462                                 continue;
463                         }
464                         if (!strcmp(arg, "--no-revs")) {
465                                 filter &= ~DO_REVS;
466                                 continue;
467                         }
468                         if (!strcmp(arg, "--flags")) {
469                                 filter &= ~DO_NONFLAGS;
470                                 continue;
471                         }
472                         if (!strcmp(arg, "--no-flags")) {
473                                 filter &= ~DO_FLAGS;
474                                 continue;
475                         }
476                         if (!strcmp(arg, "--verify")) {
477                                 filter &= ~(DO_FLAGS|DO_NOREV);
478                                 verify = 1;
479                                 continue;
480                         }
481                         if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
482                                 quiet = 1;
483                                 continue;
484                         }
485                         if (!strcmp(arg, "--short") ||
486                             !prefixcmp(arg, "--short=")) {
487                                 filter &= ~(DO_FLAGS|DO_NOREV);
488                                 verify = 1;
489                                 abbrev = DEFAULT_ABBREV;
490                                 if (arg[7] == '=')
491                                         abbrev = strtoul(arg + 8, NULL, 10);
492                                 if (abbrev < MINIMUM_ABBREV)
493                                         abbrev = MINIMUM_ABBREV;
494                                 else if (40 <= abbrev)
495                                         abbrev = 40;
496                                 continue;
497                         }
498                         if (!strcmp(arg, "--sq")) {
499                                 output_sq = 1;
500                                 continue;
501                         }
502                         if (!strcmp(arg, "--not")) {
503                                 show_type ^= REVERSED;
504                                 continue;
505                         }
506                         if (!strcmp(arg, "--symbolic")) {
507                                 symbolic = SHOW_SYMBOLIC_ASIS;
508                                 continue;
509                         }
510                         if (!strcmp(arg, "--symbolic-full-name")) {
511                                 symbolic = SHOW_SYMBOLIC_FULL;
512                                 continue;
513                         }
514                         if (!prefixcmp(arg, "--abbrev-ref") &&
515                             (!arg[12] || arg[12] == '=')) {
516                                 abbrev_ref = 1;
517                                 abbrev_ref_strict = warn_ambiguous_refs;
518                                 if (arg[12] == '=') {
519                                         if (!strcmp(arg + 13, "strict"))
520                                                 abbrev_ref_strict = 1;
521                                         else if (!strcmp(arg + 13, "loose"))
522                                                 abbrev_ref_strict = 0;
523                                         else
524                                                 die("unknown mode for %s", arg);
525                                 }
526                                 continue;
527                         }
528                         if (!strcmp(arg, "--all")) {
529                                 for_each_ref(show_reference, NULL);
530                                 continue;
531                         }
532                         if (!strcmp(arg, "--branches")) {
533                                 for_each_branch_ref(show_reference, NULL);
534                                 continue;
535                         }
536                         if (!strcmp(arg, "--tags")) {
537                                 for_each_tag_ref(show_reference, NULL);
538                                 continue;
539                         }
540                         if (!strcmp(arg, "--remotes")) {
541                                 for_each_remote_ref(show_reference, NULL);
542                                 continue;
543                         }
544                         if (!strcmp(arg, "--show-prefix")) {
545                                 if (prefix)
546                                         puts(prefix);
547                                 continue;
548                         }
549                         if (!strcmp(arg, "--show-cdup")) {
550                                 const char *pfx = prefix;
551                                 if (!is_inside_work_tree()) {
552                                         const char *work_tree =
553                                                 get_git_work_tree();
554                                         if (work_tree)
555                                                 printf("%s\n", work_tree);
556                                         continue;
557                                 }
558                                 while (pfx) {
559                                         pfx = strchr(pfx, '/');
560                                         if (pfx) {
561                                                 pfx++;
562                                                 printf("../");
563                                         }
564                                 }
565                                 putchar('\n');
566                                 continue;
567                         }
568                         if (!strcmp(arg, "--git-dir")) {
569                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
570                                 static char cwd[PATH_MAX];
571                                 if (gitdir) {
572                                         puts(gitdir);
573                                         continue;
574                                 }
575                                 if (!prefix) {
576                                         puts(".git");
577                                         continue;
578                                 }
579                                 if (!getcwd(cwd, PATH_MAX))
580                                         die("unable to get current working directory");
581                                 printf("%s/.git\n", cwd);
582                                 continue;
583                         }
584                         if (!strcmp(arg, "--is-inside-git-dir")) {
585                                 printf("%s\n", is_inside_git_dir() ? "true"
586                                                 : "false");
587                                 continue;
588                         }
589                         if (!strcmp(arg, "--is-inside-work-tree")) {
590                                 printf("%s\n", is_inside_work_tree() ? "true"
591                                                 : "false");
592                                 continue;
593                         }
594                         if (!strcmp(arg, "--is-bare-repository")) {
595                                 printf("%s\n", is_bare_repository() ? "true"
596                                                 : "false");
597                                 continue;
598                         }
599                         if (!prefixcmp(arg, "--since=")) {
600                                 show_datestring("--max-age=", arg+8);
601                                 continue;
602                         }
603                         if (!prefixcmp(arg, "--after=")) {
604                                 show_datestring("--max-age=", arg+8);
605                                 continue;
606                         }
607                         if (!prefixcmp(arg, "--before=")) {
608                                 show_datestring("--min-age=", arg+9);
609                                 continue;
610                         }
611                         if (!prefixcmp(arg, "--until=")) {
612                                 show_datestring("--min-age=", arg+8);
613                                 continue;
614                         }
615                         if (show_flag(arg) && verify)
616                                 die_no_single_rev(quiet);
617                         continue;
618                 }
619
620                 /* Not a flag argument */
621                 if (try_difference(arg))
622                         continue;
623                 if (try_parent_shorthands(arg))
624                         continue;
625                 name = arg;
626                 type = NORMAL;
627                 if (*arg == '^') {
628                         name++;
629                         type = REVERSED;
630                 }
631                 if (!get_sha1(name, sha1)) {
632                         if (verify)
633                                 revs_count++;
634                         else
635                                 show_rev(type, sha1, name);
636                         continue;
637                 }
638                 if (verify)
639                         die_no_single_rev(quiet);
640                 as_is = 1;
641                 if (!show_file(arg))
642                         continue;
643                 verify_filename(prefix, arg);
644         }
645         if (verify) {
646                 if (revs_count == 1) {
647                         show_rev(type, sha1, name);
648                         return 0;
649                 } else if (revs_count == 0 && show_default())
650                         return 0;
651                 die_no_single_rev(quiet);
652         } else
653                 show_default();
654         return 0;
655 }