Merge branch 'jc/calloc-pathspec'
[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_list *n = exclude->next;
285                                 show_rev(REVERSED,
286                                          exclude->item->object.sha1,NULL);
287                                 free(exclude);
288                                 exclude = n;
289                         }
290                 }
291                 *dotdot = '.';
292                 return 1;
293         }
294         *dotdot = '.';
295         return 0;
296 }
297
298 static int try_parent_shorthands(const char *arg)
299 {
300         char *dotdot;
301         unsigned char sha1[20];
302         struct commit *commit;
303         struct commit_list *parents;
304         int parents_only;
305
306         if ((dotdot = strstr(arg, "^!")))
307                 parents_only = 0;
308         else if ((dotdot = strstr(arg, "^@")))
309                 parents_only = 1;
310
311         if (!dotdot || dotdot[2])
312                 return 0;
313
314         *dotdot = 0;
315         if (get_sha1_committish(arg, sha1)) {
316                 *dotdot = '^';
317                 return 0;
318         }
319
320         if (!parents_only)
321                 show_rev(NORMAL, sha1, arg);
322         commit = lookup_commit_reference(sha1);
323         for (parents = commit->parents; parents; parents = parents->next)
324                 show_rev(parents_only ? NORMAL : REVERSED,
325                                 parents->item->object.sha1, arg);
326
327         *dotdot = '^';
328         return 1;
329 }
330
331 static int parseopt_dump(const struct option *o, const char *arg, int unset)
332 {
333         struct strbuf *parsed = o->value;
334         if (unset)
335                 strbuf_addf(parsed, " --no-%s", o->long_name);
336         else if (o->short_name && (o->long_name == NULL || !stuck_long))
337                 strbuf_addf(parsed, " -%c", o->short_name);
338         else
339                 strbuf_addf(parsed, " --%s", o->long_name);
340         if (arg) {
341                 if (!stuck_long)
342                         strbuf_addch(parsed, ' ');
343                 else if (o->long_name)
344                         strbuf_addch(parsed, '=');
345                 sq_quote_buf(parsed, arg);
346         }
347         return 0;
348 }
349
350 static const char *skipspaces(const char *s)
351 {
352         while (isspace(*s))
353                 s++;
354         return s;
355 }
356
357 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
358 {
359         static int keep_dashdash = 0, stop_at_non_option = 0;
360         static char const * const parseopt_usage[] = {
361                 N_("git rev-parse --parseopt [<options>] -- [<args>...]"),
362                 NULL
363         };
364         static struct option parseopt_opts[] = {
365                 OPT_BOOL(0, "keep-dashdash", &keep_dashdash,
366                                         N_("keep the `--` passed as an arg")),
367                 OPT_BOOL(0, "stop-at-non-option", &stop_at_non_option,
368                                         N_("stop parsing after the "
369                                            "first non-option argument")),
370                 OPT_BOOL(0, "stuck-long", &stuck_long,
371                                         N_("output in stuck long form")),
372                 OPT_END(),
373         };
374         static const char * const flag_chars = "*=?!";
375
376         struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
377         const char **usage = NULL;
378         struct option *opts = NULL;
379         int onb = 0, osz = 0, unb = 0, usz = 0;
380
381         strbuf_addstr(&parsed, "set --");
382         argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
383                              PARSE_OPT_KEEP_DASHDASH);
384         if (argc < 1 || strcmp(argv[0], "--"))
385                 usage_with_options(parseopt_usage, parseopt_opts);
386
387         /* get the usage up to the first line with a -- on it */
388         for (;;) {
389                 if (strbuf_getline(&sb, stdin, '\n') == EOF)
390                         die("premature end of input");
391                 ALLOC_GROW(usage, unb + 1, usz);
392                 if (!strcmp("--", sb.buf)) {
393                         if (unb < 1)
394                                 die("no usage string given before the `--' separator");
395                         usage[unb] = NULL;
396                         break;
397                 }
398                 usage[unb++] = strbuf_detach(&sb, NULL);
399         }
400
401         /* parse: (<short>|<short>,<long>|<long>)[*=?!]*<arghint>? SP+ <help> */
402         while (strbuf_getline(&sb, stdin, '\n') != EOF) {
403                 const char *s;
404                 const char *help;
405                 struct option *o;
406
407                 if (!sb.len)
408                         continue;
409
410                 ALLOC_GROW(opts, onb + 1, osz);
411                 memset(opts + onb, 0, sizeof(opts[onb]));
412
413                 o = &opts[onb++];
414                 help = strchr(sb.buf, ' ');
415                 if (!help || *sb.buf == ' ') {
416                         o->type = OPTION_GROUP;
417                         o->help = xstrdup(skipspaces(sb.buf));
418                         continue;
419                 }
420
421                 o->type = OPTION_CALLBACK;
422                 o->help = xstrdup(skipspaces(help));
423                 o->value = &parsed;
424                 o->flags = PARSE_OPT_NOARG;
425                 o->callback = &parseopt_dump;
426
427                 /* name(s) */
428                 s = strpbrk(sb.buf, flag_chars);
429                 if (s == NULL)
430                         s = help;
431
432                 if (s - sb.buf == 1) /* short option only */
433                         o->short_name = *sb.buf;
434                 else if (sb.buf[1] != ',') /* long option only */
435                         o->long_name = xmemdupz(sb.buf, s - sb.buf);
436                 else {
437                         o->short_name = *sb.buf;
438                         o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
439                 }
440
441                 /* flags */
442                 while (s < help) {
443                         switch (*s++) {
444                         case '=':
445                                 o->flags &= ~PARSE_OPT_NOARG;
446                                 continue;
447                         case '?':
448                                 o->flags &= ~PARSE_OPT_NOARG;
449                                 o->flags |= PARSE_OPT_OPTARG;
450                                 continue;
451                         case '!':
452                                 o->flags |= PARSE_OPT_NONEG;
453                                 continue;
454                         case '*':
455                                 o->flags |= PARSE_OPT_HIDDEN;
456                                 continue;
457                         }
458                         s--;
459                         break;
460                 }
461
462                 if (s < help)
463                         o->argh = xmemdupz(s, help - s);
464         }
465         strbuf_release(&sb);
466
467         /* put an OPT_END() */
468         ALLOC_GROW(opts, onb + 1, osz);
469         memset(opts + onb, 0, sizeof(opts[onb]));
470         argc = parse_options(argc, argv, prefix, opts, usage,
471                         (keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0) |
472                         (stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0) |
473                         PARSE_OPT_SHELL_EVAL);
474
475         strbuf_addf(&parsed, " --");
476         sq_quote_argv(&parsed, argv, 0);
477         puts(parsed.buf);
478         return 0;
479 }
480
481 static int cmd_sq_quote(int argc, const char **argv)
482 {
483         struct strbuf buf = STRBUF_INIT;
484
485         if (argc)
486                 sq_quote_argv(&buf, argv, 0);
487         printf("%s\n", buf.buf);
488         strbuf_release(&buf);
489
490         return 0;
491 }
492
493 static void die_no_single_rev(int quiet)
494 {
495         if (quiet)
496                 exit(1);
497         else
498                 die("Needed a single revision");
499 }
500
501 static const char builtin_rev_parse_usage[] =
502 N_("git rev-parse --parseopt [<options>] -- [<args>...]\n"
503    "   or: git rev-parse --sq-quote [<arg>...]\n"
504    "   or: git rev-parse [<options>] [<arg>...]\n"
505    "\n"
506    "Run \"git rev-parse --parseopt -h\" for more information on the first usage.");
507
508 int cmd_rev_parse(int argc, const char **argv, const char *prefix)
509 {
510         int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
511         int has_dashdash = 0;
512         int output_prefix = 0;
513         unsigned char sha1[20];
514         unsigned int flags = 0;
515         const char *name = NULL;
516         struct object_context unused;
517
518         if (argc > 1 && !strcmp("--parseopt", argv[1]))
519                 return cmd_parseopt(argc - 1, argv + 1, prefix);
520
521         if (argc > 1 && !strcmp("--sq-quote", argv[1]))
522                 return cmd_sq_quote(argc - 2, argv + 2);
523
524         if (argc > 1 && !strcmp("-h", argv[1]))
525                 usage(builtin_rev_parse_usage);
526
527         for (i = 1; i < argc; i++) {
528                 if (!strcmp(argv[i], "--")) {
529                         has_dashdash = 1;
530                         break;
531                 }
532         }
533
534         prefix = setup_git_directory();
535         git_config(git_default_config, NULL);
536         for (i = 1; i < argc; i++) {
537                 const char *arg = argv[i];
538
539                 if (!strcmp(arg, "--git-path")) {
540                         if (!argv[i + 1])
541                                 die("--git-path requires an argument");
542                         puts(git_path("%s", argv[i + 1]));
543                         i++;
544                         continue;
545                 }
546                 if (as_is) {
547                         if (show_file(arg, output_prefix) && as_is < 2)
548                                 verify_filename(prefix, arg, 0);
549                         continue;
550                 }
551                 if (!strcmp(arg,"-n")) {
552                         if (++i >= argc)
553                                 die("-n requires an argument");
554                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
555                                 show(arg);
556                                 show(argv[i]);
557                         }
558                         continue;
559                 }
560                 if (starts_with(arg, "-n")) {
561                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
562                                 show(arg);
563                         continue;
564                 }
565
566                 if (*arg == '-') {
567                         if (!strcmp(arg, "--")) {
568                                 as_is = 2;
569                                 /* Pass on the "--" if we show anything but files.. */
570                                 if (filter & (DO_FLAGS | DO_REVS))
571                                         show_file(arg, 0);
572                                 continue;
573                         }
574                         if (!strcmp(arg, "--default")) {
575                                 def = argv[++i];
576                                 if (!def)
577                                         die("--default requires an argument");
578                                 continue;
579                         }
580                         if (!strcmp(arg, "--prefix")) {
581                                 prefix = argv[++i];
582                                 if (!prefix)
583                                         die("--prefix requires an argument");
584                                 startup_info->prefix = prefix;
585                                 output_prefix = 1;
586                                 continue;
587                         }
588                         if (!strcmp(arg, "--revs-only")) {
589                                 filter &= ~DO_NOREV;
590                                 continue;
591                         }
592                         if (!strcmp(arg, "--no-revs")) {
593                                 filter &= ~DO_REVS;
594                                 continue;
595                         }
596                         if (!strcmp(arg, "--flags")) {
597                                 filter &= ~DO_NONFLAGS;
598                                 continue;
599                         }
600                         if (!strcmp(arg, "--no-flags")) {
601                                 filter &= ~DO_FLAGS;
602                                 continue;
603                         }
604                         if (!strcmp(arg, "--verify")) {
605                                 filter &= ~(DO_FLAGS|DO_NOREV);
606                                 verify = 1;
607                                 continue;
608                         }
609                         if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
610                                 quiet = 1;
611                                 flags |= GET_SHA1_QUIETLY;
612                                 continue;
613                         }
614                         if (!strcmp(arg, "--short") ||
615                             starts_with(arg, "--short=")) {
616                                 filter &= ~(DO_FLAGS|DO_NOREV);
617                                 verify = 1;
618                                 abbrev = DEFAULT_ABBREV;
619                                 if (arg[7] == '=')
620                                         abbrev = strtoul(arg + 8, NULL, 10);
621                                 if (abbrev < MINIMUM_ABBREV)
622                                         abbrev = MINIMUM_ABBREV;
623                                 else if (40 <= abbrev)
624                                         abbrev = 40;
625                                 continue;
626                         }
627                         if (!strcmp(arg, "--sq")) {
628                                 output_sq = 1;
629                                 continue;
630                         }
631                         if (!strcmp(arg, "--not")) {
632                                 show_type ^= REVERSED;
633                                 continue;
634                         }
635                         if (!strcmp(arg, "--symbolic")) {
636                                 symbolic = SHOW_SYMBOLIC_ASIS;
637                                 continue;
638                         }
639                         if (!strcmp(arg, "--symbolic-full-name")) {
640                                 symbolic = SHOW_SYMBOLIC_FULL;
641                                 continue;
642                         }
643                         if (starts_with(arg, "--abbrev-ref") &&
644                             (!arg[12] || arg[12] == '=')) {
645                                 abbrev_ref = 1;
646                                 abbrev_ref_strict = warn_ambiguous_refs;
647                                 if (arg[12] == '=') {
648                                         if (!strcmp(arg + 13, "strict"))
649                                                 abbrev_ref_strict = 1;
650                                         else if (!strcmp(arg + 13, "loose"))
651                                                 abbrev_ref_strict = 0;
652                                         else
653                                                 die("unknown mode for %s", arg);
654                                 }
655                                 continue;
656                         }
657                         if (!strcmp(arg, "--all")) {
658                                 for_each_ref(show_reference, NULL);
659                                 continue;
660                         }
661                         if (starts_with(arg, "--disambiguate=")) {
662                                 for_each_abbrev(arg + 15, show_abbrev, NULL);
663                                 continue;
664                         }
665                         if (!strcmp(arg, "--bisect")) {
666                                 for_each_ref_in("refs/bisect/bad", show_reference, NULL);
667                                 for_each_ref_in("refs/bisect/good", anti_reference, NULL);
668                                 continue;
669                         }
670                         if (starts_with(arg, "--branches=")) {
671                                 for_each_glob_ref_in(show_reference, arg + 11,
672                                         "refs/heads/", NULL);
673                                 clear_ref_exclusion(&ref_excludes);
674                                 continue;
675                         }
676                         if (!strcmp(arg, "--branches")) {
677                                 for_each_branch_ref(show_reference, NULL);
678                                 clear_ref_exclusion(&ref_excludes);
679                                 continue;
680                         }
681                         if (starts_with(arg, "--tags=")) {
682                                 for_each_glob_ref_in(show_reference, arg + 7,
683                                         "refs/tags/", NULL);
684                                 clear_ref_exclusion(&ref_excludes);
685                                 continue;
686                         }
687                         if (!strcmp(arg, "--tags")) {
688                                 for_each_tag_ref(show_reference, NULL);
689                                 clear_ref_exclusion(&ref_excludes);
690                                 continue;
691                         }
692                         if (starts_with(arg, "--glob=")) {
693                                 for_each_glob_ref(show_reference, arg + 7, NULL);
694                                 clear_ref_exclusion(&ref_excludes);
695                                 continue;
696                         }
697                         if (starts_with(arg, "--remotes=")) {
698                                 for_each_glob_ref_in(show_reference, arg + 10,
699                                         "refs/remotes/", NULL);
700                                 clear_ref_exclusion(&ref_excludes);
701                                 continue;
702                         }
703                         if (!strcmp(arg, "--remotes")) {
704                                 for_each_remote_ref(show_reference, NULL);
705                                 clear_ref_exclusion(&ref_excludes);
706                                 continue;
707                         }
708                         if (starts_with(arg, "--exclude=")) {
709                                 add_ref_exclusion(&ref_excludes, arg + 10);
710                                 continue;
711                         }
712                         if (!strcmp(arg, "--local-env-vars")) {
713                                 int i;
714                                 for (i = 0; local_repo_env[i]; i++)
715                                         printf("%s\n", local_repo_env[i]);
716                                 continue;
717                         }
718                         if (!strcmp(arg, "--show-toplevel")) {
719                                 const char *work_tree = get_git_work_tree();
720                                 if (work_tree)
721                                         puts(work_tree);
722                                 continue;
723                         }
724                         if (!strcmp(arg, "--show-prefix")) {
725                                 if (prefix)
726                                         puts(prefix);
727                                 else
728                                         putchar('\n');
729                                 continue;
730                         }
731                         if (!strcmp(arg, "--show-cdup")) {
732                                 const char *pfx = prefix;
733                                 if (!is_inside_work_tree()) {
734                                         const char *work_tree =
735                                                 get_git_work_tree();
736                                         if (work_tree)
737                                                 printf("%s\n", work_tree);
738                                         continue;
739                                 }
740                                 while (pfx) {
741                                         pfx = strchr(pfx, '/');
742                                         if (pfx) {
743                                                 pfx++;
744                                                 printf("../");
745                                         }
746                                 }
747                                 putchar('\n');
748                                 continue;
749                         }
750                         if (!strcmp(arg, "--git-dir")) {
751                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
752                                 char *cwd;
753                                 int len;
754                                 if (gitdir) {
755                                         puts(gitdir);
756                                         continue;
757                                 }
758                                 if (!prefix) {
759                                         puts(".git");
760                                         continue;
761                                 }
762                                 cwd = xgetcwd();
763                                 len = strlen(cwd);
764                                 printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
765                                 free(cwd);
766                                 continue;
767                         }
768                         if (!strcmp(arg, "--git-common-dir")) {
769                                 puts(get_git_common_dir());
770                                 continue;
771                         }
772                         if (!strcmp(arg, "--resolve-git-dir")) {
773                                 const char *gitdir = argv[++i];
774                                 if (!gitdir)
775                                         die("--resolve-git-dir requires an argument");
776                                 gitdir = resolve_gitdir(gitdir);
777                                 if (!gitdir)
778                                         die("not a gitdir '%s'", argv[i]);
779                                 puts(gitdir);
780                                 continue;
781                         }
782                         if (!strcmp(arg, "--is-inside-git-dir")) {
783                                 printf("%s\n", is_inside_git_dir() ? "true"
784                                                 : "false");
785                                 continue;
786                         }
787                         if (!strcmp(arg, "--is-inside-work-tree")) {
788                                 printf("%s\n", is_inside_work_tree() ? "true"
789                                                 : "false");
790                                 continue;
791                         }
792                         if (!strcmp(arg, "--is-bare-repository")) {
793                                 printf("%s\n", is_bare_repository() ? "true"
794                                                 : "false");
795                                 continue;
796                         }
797                         if (!strcmp(arg, "--shared-index-path")) {
798                                 if (read_cache() < 0)
799                                         die(_("Could not read the index"));
800                                 if (the_index.split_index) {
801                                         const unsigned char *sha1 = the_index.split_index->base_sha1;
802                                         puts(git_path("sharedindex.%s", sha1_to_hex(sha1)));
803                                 }
804                                 continue;
805                         }
806                         if (starts_with(arg, "--since=")) {
807                                 show_datestring("--max-age=", arg+8);
808                                 continue;
809                         }
810                         if (starts_with(arg, "--after=")) {
811                                 show_datestring("--max-age=", arg+8);
812                                 continue;
813                         }
814                         if (starts_with(arg, "--before=")) {
815                                 show_datestring("--min-age=", arg+9);
816                                 continue;
817                         }
818                         if (starts_with(arg, "--until=")) {
819                                 show_datestring("--min-age=", arg+8);
820                                 continue;
821                         }
822                         if (show_flag(arg) && verify)
823                                 die_no_single_rev(quiet);
824                         continue;
825                 }
826
827                 /* Not a flag argument */
828                 if (try_difference(arg))
829                         continue;
830                 if (try_parent_shorthands(arg))
831                         continue;
832                 name = arg;
833                 type = NORMAL;
834                 if (*arg == '^') {
835                         name++;
836                         type = REVERSED;
837                 }
838                 if (!get_sha1_with_context(name, flags, sha1, &unused)) {
839                         if (verify)
840                                 revs_count++;
841                         else
842                                 show_rev(type, sha1, name);
843                         continue;
844                 }
845                 if (verify)
846                         die_no_single_rev(quiet);
847                 if (has_dashdash)
848                         die("bad revision '%s'", arg);
849                 as_is = 1;
850                 if (!show_file(arg, output_prefix))
851                         continue;
852                 verify_filename(prefix, arg, 1);
853         }
854         if (verify) {
855                 if (revs_count == 1) {
856                         show_rev(type, sha1, name);
857                         return 0;
858                 } else if (revs_count == 0 && show_default())
859                         return 0;
860                 die_no_single_rev(quiet);
861         } else
862                 show_default();
863         return 0;
864 }