git-remote-mediawiki: get rid of O(N^2) loop
[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                 "--branches",
46                 "--header",
47                 "--ignore-missing",
48                 "--max-age=",
49                 "--max-count=",
50                 "--min-age=",
51                 "--no-merges",
52                 "--min-parents=",
53                 "--no-min-parents",
54                 "--max-parents=",
55                 "--no-max-parents",
56                 "--objects",
57                 "--objects-edge",
58                 "--parents",
59                 "--pretty",
60                 "--remotes=",
61                 "--remotes",
62                 "--glob=",
63                 "--sparse",
64                 "--tags=",
65                 "--tags",
66                 "--topo-order",
67                 "--date-order",
68                 "--unpacked",
69                 NULL
70         };
71         const char **p = rev_args;
72
73         /* accept -<digit>, like traditional "head" */
74         if ((*arg == '-') && isdigit(arg[1]))
75                 return 1;
76
77         for (;;) {
78                 const char *str = *p++;
79                 int len;
80                 if (!str)
81                         return 0;
82                 len = strlen(str);
83                 if (!strcmp(arg, str) ||
84                     (str[len-1] == '=' && !strncmp(arg, str, len)))
85                         return 1;
86         }
87 }
88
89 /* Output argument as a string, either SQ or normal */
90 static void show(const char *arg)
91 {
92         if (output_sq) {
93                 int sq = '\'', ch;
94
95                 putchar(sq);
96                 while ((ch = *arg++)) {
97                         if (ch == sq)
98                                 fputs("'\\'", stdout);
99                         putchar(ch);
100                 }
101                 putchar(sq);
102                 putchar(' ');
103         }
104         else
105                 puts(arg);
106 }
107
108 /* Like show(), but with a negation prefix according to type */
109 static void show_with_type(int type, const char *arg)
110 {
111         if (type != show_type)
112                 putchar('^');
113         show(arg);
114 }
115
116 /* Output a revision, only if filter allows it */
117 static void show_rev(int type, const unsigned char *sha1, const char *name)
118 {
119         if (!(filter & DO_REVS))
120                 return;
121         def = NULL;
122
123         if ((symbolic || abbrev_ref) && name) {
124                 if (symbolic == SHOW_SYMBOLIC_FULL || abbrev_ref) {
125                         unsigned char discard[20];
126                         char *full;
127
128                         switch (dwim_ref(name, strlen(name), discard, &full)) {
129                         case 0:
130                                 /*
131                                  * Not found -- not a ref.  We could
132                                  * emit "name" here, but symbolic-full
133                                  * users are interested in finding the
134                                  * refs spelled in full, and they would
135                                  * need to filter non-refs if we did so.
136                                  */
137                                 break;
138                         case 1: /* happy */
139                                 if (abbrev_ref)
140                                         full = shorten_unambiguous_ref(full,
141                                                 abbrev_ref_strict);
142                                 show_with_type(type, full);
143                                 break;
144                         default: /* ambiguous */
145                                 error("refname '%s' is ambiguous", name);
146                                 break;
147                         }
148                 } else {
149                         show_with_type(type, name);
150                 }
151         }
152         else if (abbrev)
153                 show_with_type(type, find_unique_abbrev(sha1, abbrev));
154         else
155                 show_with_type(type, sha1_to_hex(sha1));
156 }
157
158 /* Output a flag, only if filter allows it. */
159 static int show_flag(const char *arg)
160 {
161         if (!(filter & DO_FLAGS))
162                 return 0;
163         if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
164                 show(arg);
165                 return 1;
166         }
167         return 0;
168 }
169
170 static int show_default(void)
171 {
172         const char *s = def;
173
174         if (s) {
175                 unsigned char sha1[20];
176
177                 def = NULL;
178                 if (!get_sha1(s, sha1)) {
179                         show_rev(NORMAL, sha1, s);
180                         return 1;
181                 }
182         }
183         return 0;
184 }
185
186 static int show_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
187 {
188         show_rev(NORMAL, sha1, refname);
189         return 0;
190 }
191
192 static int anti_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
193 {
194         show_rev(REVERSED, sha1, refname);
195         return 0;
196 }
197
198 static void show_datestring(const char *flag, const char *datestr)
199 {
200         static char buffer[100];
201
202         /* date handling requires both flags and revs */
203         if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
204                 return;
205         snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
206         show(buffer);
207 }
208
209 static int show_file(const char *arg)
210 {
211         show_default();
212         if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
213                 show(arg);
214                 return 1;
215         }
216         return 0;
217 }
218
219 static int try_difference(const char *arg)
220 {
221         char *dotdot;
222         unsigned char sha1[20];
223         unsigned char end[20];
224         const char *next;
225         const char *this;
226         int symmetric;
227
228         if (!(dotdot = strstr(arg, "..")))
229                 return 0;
230         next = dotdot + 2;
231         this = arg;
232         symmetric = (*next == '.');
233
234         *dotdot = 0;
235         next += symmetric;
236
237         if (!*next)
238                 next = "HEAD";
239         if (dotdot == arg)
240                 this = "HEAD";
241         if (!get_sha1(this, sha1) && !get_sha1(next, end)) {
242                 show_rev(NORMAL, end, next);
243                 show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
244                 if (symmetric) {
245                         struct commit_list *exclude;
246                         struct commit *a, *b;
247                         a = lookup_commit_reference(sha1);
248                         b = lookup_commit_reference(end);
249                         exclude = get_merge_bases(a, b, 1);
250                         while (exclude) {
251                                 struct commit_list *n = exclude->next;
252                                 show_rev(REVERSED,
253                                          exclude->item->object.sha1,NULL);
254                                 free(exclude);
255                                 exclude = n;
256                         }
257                 }
258                 return 1;
259         }
260         *dotdot = '.';
261         return 0;
262 }
263
264 static int try_parent_shorthands(const char *arg)
265 {
266         char *dotdot;
267         unsigned char sha1[20];
268         struct commit *commit;
269         struct commit_list *parents;
270         int parents_only;
271
272         if ((dotdot = strstr(arg, "^!")))
273                 parents_only = 0;
274         else if ((dotdot = strstr(arg, "^@")))
275                 parents_only = 1;
276
277         if (!dotdot || dotdot[2])
278                 return 0;
279
280         *dotdot = 0;
281         if (get_sha1(arg, sha1))
282                 return 0;
283
284         if (!parents_only)
285                 show_rev(NORMAL, sha1, arg);
286         commit = lookup_commit_reference(sha1);
287         for (parents = commit->parents; parents; parents = parents->next)
288                 show_rev(parents_only ? NORMAL : REVERSED,
289                                 parents->item->object.sha1, arg);
290
291         return 1;
292 }
293
294 static int parseopt_dump(const struct option *o, const char *arg, int unset)
295 {
296         struct strbuf *parsed = o->value;
297         if (unset)
298                 strbuf_addf(parsed, " --no-%s", o->long_name);
299         else if (o->short_name)
300                 strbuf_addf(parsed, " -%c", o->short_name);
301         else
302                 strbuf_addf(parsed, " --%s", o->long_name);
303         if (arg) {
304                 strbuf_addch(parsed, ' ');
305                 sq_quote_buf(parsed, arg);
306         }
307         return 0;
308 }
309
310 static const char *skipspaces(const char *s)
311 {
312         while (isspace(*s))
313                 s++;
314         return s;
315 }
316
317 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
318 {
319         static int keep_dashdash = 0, stop_at_non_option = 0;
320         static char const * const parseopt_usage[] = {
321                 "git rev-parse --parseopt [options] -- [<args>...]",
322                 NULL
323         };
324         static struct option parseopt_opts[] = {
325                 OPT_BOOLEAN(0, "keep-dashdash", &keep_dashdash,
326                                         "keep the `--` passed as an arg"),
327                 OPT_BOOLEAN(0, "stop-at-non-option", &stop_at_non_option,
328                                         "stop parsing after the "
329                                         "first non-option argument"),
330                 OPT_END(),
331         };
332
333         struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
334         const char **usage = NULL;
335         struct option *opts = NULL;
336         int onb = 0, osz = 0, unb = 0, usz = 0;
337
338         strbuf_addstr(&parsed, "set --");
339         argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
340                              PARSE_OPT_KEEP_DASHDASH);
341         if (argc < 1 || strcmp(argv[0], "--"))
342                 usage_with_options(parseopt_usage, parseopt_opts);
343
344         /* get the usage up to the first line with a -- on it */
345         for (;;) {
346                 if (strbuf_getline(&sb, stdin, '\n') == EOF)
347                         die("premature end of input");
348                 ALLOC_GROW(usage, unb + 1, usz);
349                 if (!strcmp("--", sb.buf)) {
350                         if (unb < 1)
351                                 die("no usage string given before the `--' separator");
352                         usage[unb] = NULL;
353                         break;
354                 }
355                 usage[unb++] = strbuf_detach(&sb, NULL);
356         }
357
358         /* parse: (<short>|<short>,<long>|<long>)[=?]? SP+ <help> */
359         while (strbuf_getline(&sb, stdin, '\n') != EOF) {
360                 const char *s;
361                 struct option *o;
362
363                 if (!sb.len)
364                         continue;
365
366                 ALLOC_GROW(opts, onb + 1, osz);
367                 memset(opts + onb, 0, sizeof(opts[onb]));
368
369                 o = &opts[onb++];
370                 s = strchr(sb.buf, ' ');
371                 if (!s || *sb.buf == ' ') {
372                         o->type = OPTION_GROUP;
373                         o->help = xstrdup(skipspaces(sb.buf));
374                         continue;
375                 }
376
377                 o->type = OPTION_CALLBACK;
378                 o->help = xstrdup(skipspaces(s));
379                 o->value = &parsed;
380                 o->flags = PARSE_OPT_NOARG;
381                 o->callback = &parseopt_dump;
382                 while (s > sb.buf && strchr("*=?!", s[-1])) {
383                         switch (*--s) {
384                         case '=':
385                                 o->flags &= ~PARSE_OPT_NOARG;
386                                 break;
387                         case '?':
388                                 o->flags &= ~PARSE_OPT_NOARG;
389                                 o->flags |= PARSE_OPT_OPTARG;
390                                 break;
391                         case '!':
392                                 o->flags |= PARSE_OPT_NONEG;
393                                 break;
394                         case '*':
395                                 o->flags |= PARSE_OPT_HIDDEN;
396                                 break;
397                         }
398                 }
399
400                 if (s - sb.buf == 1) /* short option only */
401                         o->short_name = *sb.buf;
402                 else if (sb.buf[1] != ',') /* long option only */
403                         o->long_name = xmemdupz(sb.buf, s - sb.buf);
404                 else {
405                         o->short_name = *sb.buf;
406                         o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
407                 }
408         }
409         strbuf_release(&sb);
410
411         /* put an OPT_END() */
412         ALLOC_GROW(opts, onb + 1, osz);
413         memset(opts + onb, 0, sizeof(opts[onb]));
414         argc = parse_options(argc, argv, prefix, opts, usage,
415                         (keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0) |
416                         (stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0) |
417                         PARSE_OPT_SHELL_EVAL);
418
419         strbuf_addf(&parsed, " --");
420         sq_quote_argv(&parsed, argv, 0);
421         puts(parsed.buf);
422         return 0;
423 }
424
425 static int cmd_sq_quote(int argc, const char **argv)
426 {
427         struct strbuf buf = STRBUF_INIT;
428
429         if (argc)
430                 sq_quote_argv(&buf, argv, 0);
431         printf("%s\n", buf.buf);
432         strbuf_release(&buf);
433
434         return 0;
435 }
436
437 static void die_no_single_rev(int quiet)
438 {
439         if (quiet)
440                 exit(1);
441         else
442                 die("Needed a single revision");
443 }
444
445 static const char builtin_rev_parse_usage[] =
446 "git rev-parse --parseopt [options] -- [<args>...]\n"
447 "   or: git rev-parse --sq-quote [<arg>...]\n"
448 "   or: git rev-parse [options] [<arg>...]\n"
449 "\n"
450 "Run \"git rev-parse --parseopt -h\" for more information on the first usage.";
451
452 int cmd_rev_parse(int argc, const char **argv, const char *prefix)
453 {
454         int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
455         unsigned char sha1[20];
456         const char *name = NULL;
457
458         if (argc > 1 && !strcmp("--parseopt", argv[1]))
459                 return cmd_parseopt(argc - 1, argv + 1, prefix);
460
461         if (argc > 1 && !strcmp("--sq-quote", argv[1]))
462                 return cmd_sq_quote(argc - 2, argv + 2);
463
464         if (argc == 2 && !strcmp("--local-env-vars", argv[1])) {
465                 int i;
466                 for (i = 0; local_repo_env[i]; i++)
467                         printf("%s\n", local_repo_env[i]);
468                 return 0;
469         }
470
471         if (argc > 2 && !strcmp(argv[1], "--resolve-git-dir")) {
472                 const char *gitdir = resolve_gitdir(argv[2]);
473                 if (!gitdir)
474                         die("not a gitdir '%s'", argv[2]);
475                 puts(gitdir);
476                 return 0;
477         }
478
479         if (argc > 1 && !strcmp("-h", argv[1]))
480                 usage(builtin_rev_parse_usage);
481
482         prefix = setup_git_directory();
483         git_config(git_default_config, NULL);
484         for (i = 1; i < argc; i++) {
485                 const char *arg = argv[i];
486
487                 if (as_is) {
488                         if (show_file(arg) && as_is < 2)
489                                 verify_filename(prefix, arg, 0);
490                         continue;
491                 }
492                 if (!strcmp(arg,"-n")) {
493                         if (++i >= argc)
494                                 die("-n requires an argument");
495                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
496                                 show(arg);
497                                 show(argv[i]);
498                         }
499                         continue;
500                 }
501                 if (!prefixcmp(arg, "-n")) {
502                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
503                                 show(arg);
504                         continue;
505                 }
506
507                 if (*arg == '-') {
508                         if (!strcmp(arg, "--")) {
509                                 as_is = 2;
510                                 /* Pass on the "--" if we show anything but files.. */
511                                 if (filter & (DO_FLAGS | DO_REVS))
512                                         show_file(arg);
513                                 continue;
514                         }
515                         if (!strcmp(arg, "--default")) {
516                                 def = argv[i+1];
517                                 i++;
518                                 continue;
519                         }
520                         if (!strcmp(arg, "--revs-only")) {
521                                 filter &= ~DO_NOREV;
522                                 continue;
523                         }
524                         if (!strcmp(arg, "--no-revs")) {
525                                 filter &= ~DO_REVS;
526                                 continue;
527                         }
528                         if (!strcmp(arg, "--flags")) {
529                                 filter &= ~DO_NONFLAGS;
530                                 continue;
531                         }
532                         if (!strcmp(arg, "--no-flags")) {
533                                 filter &= ~DO_FLAGS;
534                                 continue;
535                         }
536                         if (!strcmp(arg, "--verify")) {
537                                 filter &= ~(DO_FLAGS|DO_NOREV);
538                                 verify = 1;
539                                 continue;
540                         }
541                         if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
542                                 quiet = 1;
543                                 continue;
544                         }
545                         if (!strcmp(arg, "--short") ||
546                             !prefixcmp(arg, "--short=")) {
547                                 filter &= ~(DO_FLAGS|DO_NOREV);
548                                 verify = 1;
549                                 abbrev = DEFAULT_ABBREV;
550                                 if (arg[7] == '=')
551                                         abbrev = strtoul(arg + 8, NULL, 10);
552                                 if (abbrev < MINIMUM_ABBREV)
553                                         abbrev = MINIMUM_ABBREV;
554                                 else if (40 <= abbrev)
555                                         abbrev = 40;
556                                 continue;
557                         }
558                         if (!strcmp(arg, "--sq")) {
559                                 output_sq = 1;
560                                 continue;
561                         }
562                         if (!strcmp(arg, "--not")) {
563                                 show_type ^= REVERSED;
564                                 continue;
565                         }
566                         if (!strcmp(arg, "--symbolic")) {
567                                 symbolic = SHOW_SYMBOLIC_ASIS;
568                                 continue;
569                         }
570                         if (!strcmp(arg, "--symbolic-full-name")) {
571                                 symbolic = SHOW_SYMBOLIC_FULL;
572                                 continue;
573                         }
574                         if (!prefixcmp(arg, "--abbrev-ref") &&
575                             (!arg[12] || arg[12] == '=')) {
576                                 abbrev_ref = 1;
577                                 abbrev_ref_strict = warn_ambiguous_refs;
578                                 if (arg[12] == '=') {
579                                         if (!strcmp(arg + 13, "strict"))
580                                                 abbrev_ref_strict = 1;
581                                         else if (!strcmp(arg + 13, "loose"))
582                                                 abbrev_ref_strict = 0;
583                                         else
584                                                 die("unknown mode for %s", arg);
585                                 }
586                                 continue;
587                         }
588                         if (!strcmp(arg, "--all")) {
589                                 for_each_ref(show_reference, NULL);
590                                 continue;
591                         }
592                         if (!strcmp(arg, "--bisect")) {
593                                 for_each_ref_in("refs/bisect/bad", show_reference, NULL);
594                                 for_each_ref_in("refs/bisect/good", anti_reference, NULL);
595                                 continue;
596                         }
597                         if (!prefixcmp(arg, "--branches=")) {
598                                 for_each_glob_ref_in(show_reference, arg + 11,
599                                         "refs/heads/", NULL);
600                                 continue;
601                         }
602                         if (!strcmp(arg, "--branches")) {
603                                 for_each_branch_ref(show_reference, NULL);
604                                 continue;
605                         }
606                         if (!prefixcmp(arg, "--tags=")) {
607                                 for_each_glob_ref_in(show_reference, arg + 7,
608                                         "refs/tags/", NULL);
609                                 continue;
610                         }
611                         if (!strcmp(arg, "--tags")) {
612                                 for_each_tag_ref(show_reference, NULL);
613                                 continue;
614                         }
615                         if (!prefixcmp(arg, "--glob=")) {
616                                 for_each_glob_ref(show_reference, arg + 7, NULL);
617                                 continue;
618                         }
619                         if (!prefixcmp(arg, "--remotes=")) {
620                                 for_each_glob_ref_in(show_reference, arg + 10,
621                                         "refs/remotes/", NULL);
622                                 continue;
623                         }
624                         if (!strcmp(arg, "--remotes")) {
625                                 for_each_remote_ref(show_reference, NULL);
626                                 continue;
627                         }
628                         if (!strcmp(arg, "--show-toplevel")) {
629                                 const char *work_tree = get_git_work_tree();
630                                 if (work_tree)
631                                         puts(work_tree);
632                                 continue;
633                         }
634                         if (!strcmp(arg, "--show-prefix")) {
635                                 if (prefix)
636                                         puts(prefix);
637                                 else
638                                         putchar('\n');
639                                 continue;
640                         }
641                         if (!strcmp(arg, "--show-cdup")) {
642                                 const char *pfx = prefix;
643                                 if (!is_inside_work_tree()) {
644                                         const char *work_tree =
645                                                 get_git_work_tree();
646                                         if (work_tree)
647                                                 printf("%s\n", work_tree);
648                                         continue;
649                                 }
650                                 while (pfx) {
651                                         pfx = strchr(pfx, '/');
652                                         if (pfx) {
653                                                 pfx++;
654                                                 printf("../");
655                                         }
656                                 }
657                                 putchar('\n');
658                                 continue;
659                         }
660                         if (!strcmp(arg, "--git-dir")) {
661                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
662                                 static char cwd[PATH_MAX];
663                                 int len;
664                                 if (gitdir) {
665                                         puts(gitdir);
666                                         continue;
667                                 }
668                                 if (!prefix) {
669                                         puts(".git");
670                                         continue;
671                                 }
672                                 if (!getcwd(cwd, PATH_MAX))
673                                         die_errno("unable to get current working directory");
674                                 len = strlen(cwd);
675                                 printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
676                                 continue;
677                         }
678                         if (!strcmp(arg, "--is-inside-git-dir")) {
679                                 printf("%s\n", is_inside_git_dir() ? "true"
680                                                 : "false");
681                                 continue;
682                         }
683                         if (!strcmp(arg, "--is-inside-work-tree")) {
684                                 printf("%s\n", is_inside_work_tree() ? "true"
685                                                 : "false");
686                                 continue;
687                         }
688                         if (!strcmp(arg, "--is-bare-repository")) {
689                                 printf("%s\n", is_bare_repository() ? "true"
690                                                 : "false");
691                                 continue;
692                         }
693                         if (!prefixcmp(arg, "--since=")) {
694                                 show_datestring("--max-age=", arg+8);
695                                 continue;
696                         }
697                         if (!prefixcmp(arg, "--after=")) {
698                                 show_datestring("--max-age=", arg+8);
699                                 continue;
700                         }
701                         if (!prefixcmp(arg, "--before=")) {
702                                 show_datestring("--min-age=", arg+9);
703                                 continue;
704                         }
705                         if (!prefixcmp(arg, "--until=")) {
706                                 show_datestring("--min-age=", arg+8);
707                                 continue;
708                         }
709                         if (show_flag(arg) && verify)
710                                 die_no_single_rev(quiet);
711                         continue;
712                 }
713
714                 /* Not a flag argument */
715                 if (try_difference(arg))
716                         continue;
717                 if (try_parent_shorthands(arg))
718                         continue;
719                 name = arg;
720                 type = NORMAL;
721                 if (*arg == '^') {
722                         name++;
723                         type = REVERSED;
724                 }
725                 if (!get_sha1(name, sha1)) {
726                         if (verify)
727                                 revs_count++;
728                         else
729                                 show_rev(type, sha1, name);
730                         continue;
731                 }
732                 if (verify)
733                         die_no_single_rev(quiet);
734                 as_is = 1;
735                 if (!show_file(arg))
736                         continue;
737                 verify_filename(prefix, arg, 1);
738         }
739         if (verify) {
740                 if (revs_count == 1) {
741                         show_rev(type, sha1, name);
742                         return 0;
743                 } else if (revs_count == 0 && show_default())
744                         return 0;
745                 die_no_single_rev(quiet);
746         } else
747                 show_default();
748         return 0;
749 }