Merge branch 'mm/push-simple-doc' into maint
[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 #include "diff.h"
13 #include "revision.h"
14 #include "split-index.h"
15
16 #define DO_REVS         1
17 #define DO_NOREV        2
18 #define DO_FLAGS        4
19 #define DO_NONFLAGS     8
20 static int filter = ~0;
21
22 static const char *def;
23
24 #define NORMAL 0
25 #define REVERSED 1
26 static int show_type = NORMAL;
27
28 #define SHOW_SYMBOLIC_ASIS 1
29 #define SHOW_SYMBOLIC_FULL 2
30 static int symbolic;
31 static int abbrev;
32 static int abbrev_ref;
33 static int abbrev_ref_strict;
34 static int output_sq;
35
36 static int stuck_long;
37 static struct string_list *ref_excludes;
38
39 /*
40  * Some arguments are relevant "revision" arguments,
41  * others are about output format or other details.
42  * This sorts it all out.
43  */
44 static int is_rev_argument(const char *arg)
45 {
46         static const char *rev_args[] = {
47                 "--all",
48                 "--bisect",
49                 "--dense",
50                 "--branches=",
51                 "--branches",
52                 "--header",
53                 "--ignore-missing",
54                 "--max-age=",
55                 "--max-count=",
56                 "--min-age=",
57                 "--no-merges",
58                 "--min-parents=",
59                 "--no-min-parents",
60                 "--max-parents=",
61                 "--no-max-parents",
62                 "--objects",
63                 "--objects-edge",
64                 "--parents",
65                 "--pretty",
66                 "--remotes=",
67                 "--remotes",
68                 "--glob=",
69                 "--sparse",
70                 "--tags=",
71                 "--tags",
72                 "--topo-order",
73                 "--date-order",
74                 "--unpacked",
75                 NULL
76         };
77         const char **p = rev_args;
78
79         /* accept -<digit>, like traditional "head" */
80         if ((*arg == '-') && isdigit(arg[1]))
81                 return 1;
82
83         for (;;) {
84                 const char *str = *p++;
85                 int len;
86                 if (!str)
87                         return 0;
88                 len = strlen(str);
89                 if (!strcmp(arg, str) ||
90                     (str[len-1] == '=' && !strncmp(arg, str, len)))
91                         return 1;
92         }
93 }
94
95 /* Output argument as a string, either SQ or normal */
96 static void show(const char *arg)
97 {
98         if (output_sq) {
99                 int sq = '\'', ch;
100
101                 putchar(sq);
102                 while ((ch = *arg++)) {
103                         if (ch == sq)
104                                 fputs("'\\'", stdout);
105                         putchar(ch);
106                 }
107                 putchar(sq);
108                 putchar(' ');
109         }
110         else
111                 puts(arg);
112 }
113
114 /* Like show(), but with a negation prefix according to type */
115 static void show_with_type(int type, const char *arg)
116 {
117         if (type != show_type)
118                 putchar('^');
119         show(arg);
120 }
121
122 /* Output a revision, only if filter allows it */
123 static void show_rev(int type, const unsigned char *sha1, const char *name)
124 {
125         if (!(filter & DO_REVS))
126                 return;
127         def = NULL;
128
129         if ((symbolic || abbrev_ref) && name) {
130                 if (symbolic == SHOW_SYMBOLIC_FULL || abbrev_ref) {
131                         unsigned char discard[20];
132                         char *full;
133
134                         switch (dwim_ref(name, strlen(name), discard, &full)) {
135                         case 0:
136                                 /*
137                                  * Not found -- not a ref.  We could
138                                  * emit "name" here, but symbolic-full
139                                  * users are interested in finding the
140                                  * refs spelled in full, and they would
141                                  * need to filter non-refs if we did so.
142                                  */
143                                 break;
144                         case 1: /* happy */
145                                 if (abbrev_ref)
146                                         full = shorten_unambiguous_ref(full,
147                                                 abbrev_ref_strict);
148                                 show_with_type(type, full);
149                                 break;
150                         default: /* ambiguous */
151                                 error("refname '%s' is ambiguous", name);
152                                 break;
153                         }
154                         free(full);
155                 } else {
156                         show_with_type(type, name);
157                 }
158         }
159         else if (abbrev)
160                 show_with_type(type, find_unique_abbrev(sha1, abbrev));
161         else
162                 show_with_type(type, sha1_to_hex(sha1));
163 }
164
165 /* Output a flag, only if filter allows it. */
166 static int show_flag(const char *arg)
167 {
168         if (!(filter & DO_FLAGS))
169                 return 0;
170         if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
171                 show(arg);
172                 return 1;
173         }
174         return 0;
175 }
176
177 static int show_default(void)
178 {
179         const char *s = def;
180
181         if (s) {
182                 unsigned char sha1[20];
183
184                 def = NULL;
185                 if (!get_sha1(s, sha1)) {
186                         show_rev(NORMAL, sha1, s);
187                         return 1;
188                 }
189         }
190         return 0;
191 }
192
193 static int show_reference(const char *refname, const struct object_id *oid, int flag, void *cb_data)
194 {
195         if (ref_excluded(ref_excludes, refname))
196                 return 0;
197         show_rev(NORMAL, oid->hash, refname);
198         return 0;
199 }
200
201 static int anti_reference(const char *refname, const struct object_id *oid, int flag, void *cb_data)
202 {
203         show_rev(REVERSED, oid->hash, refname);
204         return 0;
205 }
206
207 static int show_abbrev(const unsigned char *sha1, void *cb_data)
208 {
209         show_rev(NORMAL, sha1, NULL);
210         return 0;
211 }
212
213 static void show_datestring(const char *flag, const char *datestr)
214 {
215         static char buffer[100];
216
217         /* date handling requires both flags and revs */
218         if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
219                 return;
220         snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
221         show(buffer);
222 }
223
224 static int show_file(const char *arg, int output_prefix)
225 {
226         show_default();
227         if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
228                 if (output_prefix) {
229                         const char *prefix = startup_info->prefix;
230                         show(prefix_filename(prefix,
231                                              prefix ? strlen(prefix) : 0,
232                                              arg));
233                 } else
234                         show(arg);
235                 return 1;
236         }
237         return 0;
238 }
239
240 static int try_difference(const char *arg)
241 {
242         char *dotdot;
243         unsigned char sha1[20];
244         unsigned char end[20];
245         const char *next;
246         const char *this;
247         int symmetric;
248         static const char head_by_default[] = "HEAD";
249
250         if (!(dotdot = strstr(arg, "..")))
251                 return 0;
252         next = dotdot + 2;
253         this = arg;
254         symmetric = (*next == '.');
255
256         *dotdot = 0;
257         next += symmetric;
258
259         if (!*next)
260                 next = head_by_default;
261         if (dotdot == arg)
262                 this = head_by_default;
263
264         if (this == head_by_default && next == head_by_default &&
265             !symmetric) {
266                 /*
267                  * Just ".."?  That is not a range but the
268                  * pathspec for the parent directory.
269                  */
270                 *dotdot = '.';
271                 return 0;
272         }
273
274         if (!get_sha1_committish(this, sha1) && !get_sha1_committish(next, end)) {
275                 show_rev(NORMAL, end, next);
276                 show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
277                 if (symmetric) {
278                         struct commit_list *exclude;
279                         struct commit *a, *b;
280                         a = lookup_commit_reference(sha1);
281                         b = lookup_commit_reference(end);
282                         exclude = get_merge_bases(a, b);
283                         while (exclude) {
284                                 struct commit *commit = pop_commit(&exclude);
285                                 show_rev(REVERSED, commit->object.oid.hash, NULL);
286                         }
287                 }
288                 *dotdot = '.';
289                 return 1;
290         }
291         *dotdot = '.';
292         return 0;
293 }
294
295 static int try_parent_shorthands(const char *arg)
296 {
297         char *dotdot;
298         unsigned char sha1[20];
299         struct commit *commit;
300         struct commit_list *parents;
301         int parents_only;
302
303         if ((dotdot = strstr(arg, "^!")))
304                 parents_only = 0;
305         else if ((dotdot = strstr(arg, "^@")))
306                 parents_only = 1;
307
308         if (!dotdot || dotdot[2])
309                 return 0;
310
311         *dotdot = 0;
312         if (get_sha1_committish(arg, sha1)) {
313                 *dotdot = '^';
314                 return 0;
315         }
316
317         if (!parents_only)
318                 show_rev(NORMAL, sha1, arg);
319         commit = lookup_commit_reference(sha1);
320         for (parents = commit->parents; parents; parents = parents->next)
321                 show_rev(parents_only ? NORMAL : REVERSED,
322                                 parents->item->object.oid.hash, arg);
323
324         *dotdot = '^';
325         return 1;
326 }
327
328 static int parseopt_dump(const struct option *o, const char *arg, int unset)
329 {
330         struct strbuf *parsed = o->value;
331         if (unset)
332                 strbuf_addf(parsed, " --no-%s", o->long_name);
333         else if (o->short_name && (o->long_name == NULL || !stuck_long))
334                 strbuf_addf(parsed, " -%c", o->short_name);
335         else
336                 strbuf_addf(parsed, " --%s", o->long_name);
337         if (arg) {
338                 if (!stuck_long)
339                         strbuf_addch(parsed, ' ');
340                 else if (o->long_name)
341                         strbuf_addch(parsed, '=');
342                 sq_quote_buf(parsed, arg);
343         }
344         return 0;
345 }
346
347 static const char *skipspaces(const char *s)
348 {
349         while (isspace(*s))
350                 s++;
351         return s;
352 }
353
354 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
355 {
356         static int keep_dashdash = 0, stop_at_non_option = 0;
357         static char const * const parseopt_usage[] = {
358                 N_("git rev-parse --parseopt [<options>] -- [<args>...]"),
359                 NULL
360         };
361         static struct option parseopt_opts[] = {
362                 OPT_BOOL(0, "keep-dashdash", &keep_dashdash,
363                                         N_("keep the `--` passed as an arg")),
364                 OPT_BOOL(0, "stop-at-non-option", &stop_at_non_option,
365                                         N_("stop parsing after the "
366                                            "first non-option argument")),
367                 OPT_BOOL(0, "stuck-long", &stuck_long,
368                                         N_("output in stuck long form")),
369                 OPT_END(),
370         };
371         static const char * const flag_chars = "*=?!";
372
373         struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
374         const char **usage = NULL;
375         struct option *opts = NULL;
376         int onb = 0, osz = 0, unb = 0, usz = 0;
377
378         strbuf_addstr(&parsed, "set --");
379         argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
380                              PARSE_OPT_KEEP_DASHDASH);
381         if (argc < 1 || strcmp(argv[0], "--"))
382                 usage_with_options(parseopt_usage, parseopt_opts);
383
384         /* get the usage up to the first line with a -- on it */
385         for (;;) {
386                 if (strbuf_getline(&sb, stdin, '\n') == EOF)
387                         die("premature end of input");
388                 ALLOC_GROW(usage, unb + 1, usz);
389                 if (!strcmp("--", sb.buf)) {
390                         if (unb < 1)
391                                 die("no usage string given before the `--' separator");
392                         usage[unb] = NULL;
393                         break;
394                 }
395                 usage[unb++] = strbuf_detach(&sb, NULL);
396         }
397
398         /* parse: (<short>|<short>,<long>|<long>)[*=?!]*<arghint>? SP+ <help> */
399         while (strbuf_getline(&sb, stdin, '\n') != EOF) {
400                 const char *s;
401                 const char *help;
402                 struct option *o;
403
404                 if (!sb.len)
405                         continue;
406
407                 ALLOC_GROW(opts, onb + 1, osz);
408                 memset(opts + onb, 0, sizeof(opts[onb]));
409
410                 o = &opts[onb++];
411                 help = strchr(sb.buf, ' ');
412                 if (!help || *sb.buf == ' ') {
413                         o->type = OPTION_GROUP;
414                         o->help = xstrdup(skipspaces(sb.buf));
415                         continue;
416                 }
417
418                 o->type = OPTION_CALLBACK;
419                 o->help = xstrdup(skipspaces(help));
420                 o->value = &parsed;
421                 o->flags = PARSE_OPT_NOARG;
422                 o->callback = &parseopt_dump;
423
424                 /* name(s) */
425                 s = strpbrk(sb.buf, flag_chars);
426                 if (s == NULL)
427                         s = help;
428
429                 if (s - sb.buf == 1) /* short option only */
430                         o->short_name = *sb.buf;
431                 else if (sb.buf[1] != ',') /* long option only */
432                         o->long_name = xmemdupz(sb.buf, s - sb.buf);
433                 else {
434                         o->short_name = *sb.buf;
435                         o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
436                 }
437
438                 /* flags */
439                 while (s < help) {
440                         switch (*s++) {
441                         case '=':
442                                 o->flags &= ~PARSE_OPT_NOARG;
443                                 continue;
444                         case '?':
445                                 o->flags &= ~PARSE_OPT_NOARG;
446                                 o->flags |= PARSE_OPT_OPTARG;
447                                 continue;
448                         case '!':
449                                 o->flags |= PARSE_OPT_NONEG;
450                                 continue;
451                         case '*':
452                                 o->flags |= PARSE_OPT_HIDDEN;
453                                 continue;
454                         }
455                         s--;
456                         break;
457                 }
458
459                 if (s < help)
460                         o->argh = xmemdupz(s, help - s);
461         }
462         strbuf_release(&sb);
463
464         /* put an OPT_END() */
465         ALLOC_GROW(opts, onb + 1, osz);
466         memset(opts + onb, 0, sizeof(opts[onb]));
467         argc = parse_options(argc, argv, prefix, opts, usage,
468                         (keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0) |
469                         (stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0) |
470                         PARSE_OPT_SHELL_EVAL);
471
472         strbuf_addf(&parsed, " --");
473         sq_quote_argv(&parsed, argv, 0);
474         puts(parsed.buf);
475         return 0;
476 }
477
478 static int cmd_sq_quote(int argc, const char **argv)
479 {
480         struct strbuf buf = STRBUF_INIT;
481
482         if (argc)
483                 sq_quote_argv(&buf, argv, 0);
484         printf("%s\n", buf.buf);
485         strbuf_release(&buf);
486
487         return 0;
488 }
489
490 static void die_no_single_rev(int quiet)
491 {
492         if (quiet)
493                 exit(1);
494         else
495                 die("Needed a single revision");
496 }
497
498 static const char builtin_rev_parse_usage[] =
499 N_("git rev-parse --parseopt [<options>] -- [<args>...]\n"
500    "   or: git rev-parse --sq-quote [<arg>...]\n"
501    "   or: git rev-parse [<options>] [<arg>...]\n"
502    "\n"
503    "Run \"git rev-parse --parseopt -h\" for more information on the first usage.");
504
505 int cmd_rev_parse(int argc, const char **argv, const char *prefix)
506 {
507         int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
508         int has_dashdash = 0;
509         int output_prefix = 0;
510         unsigned char sha1[20];
511         unsigned int flags = 0;
512         const char *name = NULL;
513         struct object_context unused;
514
515         if (argc > 1 && !strcmp("--parseopt", argv[1]))
516                 return cmd_parseopt(argc - 1, argv + 1, prefix);
517
518         if (argc > 1 && !strcmp("--sq-quote", argv[1]))
519                 return cmd_sq_quote(argc - 2, argv + 2);
520
521         if (argc > 1 && !strcmp("-h", argv[1]))
522                 usage(builtin_rev_parse_usage);
523
524         for (i = 1; i < argc; i++) {
525                 if (!strcmp(argv[i], "--")) {
526                         has_dashdash = 1;
527                         break;
528                 }
529         }
530
531         prefix = setup_git_directory();
532         git_config(git_default_config, NULL);
533         for (i = 1; i < argc; i++) {
534                 const char *arg = argv[i];
535
536                 if (!strcmp(arg, "--git-path")) {
537                         if (!argv[i + 1])
538                                 die("--git-path requires an argument");
539                         puts(git_path("%s", argv[i + 1]));
540                         i++;
541                         continue;
542                 }
543                 if (as_is) {
544                         if (show_file(arg, output_prefix) && as_is < 2)
545                                 verify_filename(prefix, arg, 0);
546                         continue;
547                 }
548                 if (!strcmp(arg,"-n")) {
549                         if (++i >= argc)
550                                 die("-n requires an argument");
551                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
552                                 show(arg);
553                                 show(argv[i]);
554                         }
555                         continue;
556                 }
557                 if (starts_with(arg, "-n")) {
558                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
559                                 show(arg);
560                         continue;
561                 }
562
563                 if (*arg == '-') {
564                         if (!strcmp(arg, "--")) {
565                                 as_is = 2;
566                                 /* Pass on the "--" if we show anything but files.. */
567                                 if (filter & (DO_FLAGS | DO_REVS))
568                                         show_file(arg, 0);
569                                 continue;
570                         }
571                         if (!strcmp(arg, "--default")) {
572                                 def = argv[++i];
573                                 if (!def)
574                                         die("--default requires an argument");
575                                 continue;
576                         }
577                         if (!strcmp(arg, "--prefix")) {
578                                 prefix = argv[++i];
579                                 if (!prefix)
580                                         die("--prefix requires an argument");
581                                 startup_info->prefix = prefix;
582                                 output_prefix = 1;
583                                 continue;
584                         }
585                         if (!strcmp(arg, "--revs-only")) {
586                                 filter &= ~DO_NOREV;
587                                 continue;
588                         }
589                         if (!strcmp(arg, "--no-revs")) {
590                                 filter &= ~DO_REVS;
591                                 continue;
592                         }
593                         if (!strcmp(arg, "--flags")) {
594                                 filter &= ~DO_NONFLAGS;
595                                 continue;
596                         }
597                         if (!strcmp(arg, "--no-flags")) {
598                                 filter &= ~DO_FLAGS;
599                                 continue;
600                         }
601                         if (!strcmp(arg, "--verify")) {
602                                 filter &= ~(DO_FLAGS|DO_NOREV);
603                                 verify = 1;
604                                 continue;
605                         }
606                         if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
607                                 quiet = 1;
608                                 flags |= GET_SHA1_QUIETLY;
609                                 continue;
610                         }
611                         if (!strcmp(arg, "--short") ||
612                             starts_with(arg, "--short=")) {
613                                 filter &= ~(DO_FLAGS|DO_NOREV);
614                                 verify = 1;
615                                 abbrev = DEFAULT_ABBREV;
616                                 if (arg[7] == '=')
617                                         abbrev = strtoul(arg + 8, NULL, 10);
618                                 if (abbrev < MINIMUM_ABBREV)
619                                         abbrev = MINIMUM_ABBREV;
620                                 else if (40 <= abbrev)
621                                         abbrev = 40;
622                                 continue;
623                         }
624                         if (!strcmp(arg, "--sq")) {
625                                 output_sq = 1;
626                                 continue;
627                         }
628                         if (!strcmp(arg, "--not")) {
629                                 show_type ^= REVERSED;
630                                 continue;
631                         }
632                         if (!strcmp(arg, "--symbolic")) {
633                                 symbolic = SHOW_SYMBOLIC_ASIS;
634                                 continue;
635                         }
636                         if (!strcmp(arg, "--symbolic-full-name")) {
637                                 symbolic = SHOW_SYMBOLIC_FULL;
638                                 continue;
639                         }
640                         if (starts_with(arg, "--abbrev-ref") &&
641                             (!arg[12] || arg[12] == '=')) {
642                                 abbrev_ref = 1;
643                                 abbrev_ref_strict = warn_ambiguous_refs;
644                                 if (arg[12] == '=') {
645                                         if (!strcmp(arg + 13, "strict"))
646                                                 abbrev_ref_strict = 1;
647                                         else if (!strcmp(arg + 13, "loose"))
648                                                 abbrev_ref_strict = 0;
649                                         else
650                                                 die("unknown mode for %s", arg);
651                                 }
652                                 continue;
653                         }
654                         if (!strcmp(arg, "--all")) {
655                                 for_each_ref(show_reference, NULL);
656                                 continue;
657                         }
658                         if (starts_with(arg, "--disambiguate=")) {
659                                 for_each_abbrev(arg + 15, show_abbrev, NULL);
660                                 continue;
661                         }
662                         if (!strcmp(arg, "--bisect")) {
663                                 for_each_ref_in("refs/bisect/bad", show_reference, NULL);
664                                 for_each_ref_in("refs/bisect/good", anti_reference, NULL);
665                                 continue;
666                         }
667                         if (starts_with(arg, "--branches=")) {
668                                 for_each_glob_ref_in(show_reference, arg + 11,
669                                         "refs/heads/", NULL);
670                                 clear_ref_exclusion(&ref_excludes);
671                                 continue;
672                         }
673                         if (!strcmp(arg, "--branches")) {
674                                 for_each_branch_ref(show_reference, NULL);
675                                 clear_ref_exclusion(&ref_excludes);
676                                 continue;
677                         }
678                         if (starts_with(arg, "--tags=")) {
679                                 for_each_glob_ref_in(show_reference, arg + 7,
680                                         "refs/tags/", NULL);
681                                 clear_ref_exclusion(&ref_excludes);
682                                 continue;
683                         }
684                         if (!strcmp(arg, "--tags")) {
685                                 for_each_tag_ref(show_reference, NULL);
686                                 clear_ref_exclusion(&ref_excludes);
687                                 continue;
688                         }
689                         if (starts_with(arg, "--glob=")) {
690                                 for_each_glob_ref(show_reference, arg + 7, NULL);
691                                 clear_ref_exclusion(&ref_excludes);
692                                 continue;
693                         }
694                         if (starts_with(arg, "--remotes=")) {
695                                 for_each_glob_ref_in(show_reference, arg + 10,
696                                         "refs/remotes/", NULL);
697                                 clear_ref_exclusion(&ref_excludes);
698                                 continue;
699                         }
700                         if (!strcmp(arg, "--remotes")) {
701                                 for_each_remote_ref(show_reference, NULL);
702                                 clear_ref_exclusion(&ref_excludes);
703                                 continue;
704                         }
705                         if (starts_with(arg, "--exclude=")) {
706                                 add_ref_exclusion(&ref_excludes, arg + 10);
707                                 continue;
708                         }
709                         if (!strcmp(arg, "--local-env-vars")) {
710                                 int i;
711                                 for (i = 0; local_repo_env[i]; i++)
712                                         printf("%s\n", local_repo_env[i]);
713                                 continue;
714                         }
715                         if (!strcmp(arg, "--show-toplevel")) {
716                                 const char *work_tree = get_git_work_tree();
717                                 if (work_tree)
718                                         puts(work_tree);
719                                 continue;
720                         }
721                         if (!strcmp(arg, "--show-prefix")) {
722                                 if (prefix)
723                                         puts(prefix);
724                                 else
725                                         putchar('\n');
726                                 continue;
727                         }
728                         if (!strcmp(arg, "--show-cdup")) {
729                                 const char *pfx = prefix;
730                                 if (!is_inside_work_tree()) {
731                                         const char *work_tree =
732                                                 get_git_work_tree();
733                                         if (work_tree)
734                                                 printf("%s\n", work_tree);
735                                         continue;
736                                 }
737                                 while (pfx) {
738                                         pfx = strchr(pfx, '/');
739                                         if (pfx) {
740                                                 pfx++;
741                                                 printf("../");
742                                         }
743                                 }
744                                 putchar('\n');
745                                 continue;
746                         }
747                         if (!strcmp(arg, "--git-dir")) {
748                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
749                                 char *cwd;
750                                 int len;
751                                 if (gitdir) {
752                                         puts(gitdir);
753                                         continue;
754                                 }
755                                 if (!prefix) {
756                                         puts(".git");
757                                         continue;
758                                 }
759                                 cwd = xgetcwd();
760                                 len = strlen(cwd);
761                                 printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
762                                 free(cwd);
763                                 continue;
764                         }
765                         if (!strcmp(arg, "--git-common-dir")) {
766                                 const char *pfx = prefix ? prefix : "";
767                                 puts(prefix_filename(pfx, strlen(pfx), get_git_common_dir()));
768                                 continue;
769                         }
770                         if (!strcmp(arg, "--resolve-git-dir")) {
771                                 const char *gitdir = argv[++i];
772                                 if (!gitdir)
773                                         die("--resolve-git-dir requires an argument");
774                                 gitdir = resolve_gitdir(gitdir);
775                                 if (!gitdir)
776                                         die("not a gitdir '%s'", argv[i]);
777                                 puts(gitdir);
778                                 continue;
779                         }
780                         if (!strcmp(arg, "--is-inside-git-dir")) {
781                                 printf("%s\n", is_inside_git_dir() ? "true"
782                                                 : "false");
783                                 continue;
784                         }
785                         if (!strcmp(arg, "--is-inside-work-tree")) {
786                                 printf("%s\n", is_inside_work_tree() ? "true"
787                                                 : "false");
788                                 continue;
789                         }
790                         if (!strcmp(arg, "--is-bare-repository")) {
791                                 printf("%s\n", is_bare_repository() ? "true"
792                                                 : "false");
793                                 continue;
794                         }
795                         if (!strcmp(arg, "--shared-index-path")) {
796                                 if (read_cache() < 0)
797                                         die(_("Could not read the index"));
798                                 if (the_index.split_index) {
799                                         const unsigned char *sha1 = the_index.split_index->base_sha1;
800                                         puts(git_path("sharedindex.%s", sha1_to_hex(sha1)));
801                                 }
802                                 continue;
803                         }
804                         if (starts_with(arg, "--since=")) {
805                                 show_datestring("--max-age=", arg+8);
806                                 continue;
807                         }
808                         if (starts_with(arg, "--after=")) {
809                                 show_datestring("--max-age=", arg+8);
810                                 continue;
811                         }
812                         if (starts_with(arg, "--before=")) {
813                                 show_datestring("--min-age=", arg+9);
814                                 continue;
815                         }
816                         if (starts_with(arg, "--until=")) {
817                                 show_datestring("--min-age=", arg+8);
818                                 continue;
819                         }
820                         if (show_flag(arg) && verify)
821                                 die_no_single_rev(quiet);
822                         continue;
823                 }
824
825                 /* Not a flag argument */
826                 if (try_difference(arg))
827                         continue;
828                 if (try_parent_shorthands(arg))
829                         continue;
830                 name = arg;
831                 type = NORMAL;
832                 if (*arg == '^') {
833                         name++;
834                         type = REVERSED;
835                 }
836                 if (!get_sha1_with_context(name, flags, sha1, &unused)) {
837                         if (verify)
838                                 revs_count++;
839                         else
840                                 show_rev(type, sha1, name);
841                         continue;
842                 }
843                 if (verify)
844                         die_no_single_rev(quiet);
845                 if (has_dashdash)
846                         die("bad revision '%s'", arg);
847                 as_is = 1;
848                 if (!show_file(arg, output_prefix))
849                         continue;
850                 verify_filename(prefix, arg, 1);
851         }
852         if (verify) {
853                 if (revs_count == 1) {
854                         show_rev(type, sha1, name);
855                         return 0;
856                 } else if (revs_count == 0 && show_default())
857                         return 0;
858                 die_no_single_rev(quiet);
859         } else
860                 show_default();
861         return 0;
862 }