rev-parse: add helper for parsing "--foo/--foo="
[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 parent_number;
302         int include_rev = 0;
303         int include_parents = 0;
304         int exclude_parent = 0;
305
306         if ((dotdot = strstr(arg, "^!"))) {
307                 include_rev = 1;
308                 if (dotdot[2])
309                         return 0;
310         } else if ((dotdot = strstr(arg, "^@"))) {
311                 include_parents = 1;
312                 if (dotdot[2])
313                         return 0;
314         } else if ((dotdot = strstr(arg, "^-"))) {
315                 include_rev = 1;
316                 exclude_parent = 1;
317
318                 if (dotdot[2]) {
319                         char *end;
320                         exclude_parent = strtoul(dotdot + 2, &end, 10);
321                         if (*end != '\0' || !exclude_parent)
322                                 return 0;
323                 }
324         } else
325                 return 0;
326
327         *dotdot = 0;
328         if (get_sha1_committish(arg, sha1)) {
329                 *dotdot = '^';
330                 return 0;
331         }
332
333         commit = lookup_commit_reference(sha1);
334         if (exclude_parent &&
335             exclude_parent > commit_list_count(commit->parents)) {
336                 *dotdot = '^';
337                 return 0;
338         }
339
340         if (include_rev)
341                 show_rev(NORMAL, sha1, arg);
342         for (parents = commit->parents, parent_number = 1;
343              parents;
344              parents = parents->next, parent_number++) {
345                 char *name = NULL;
346
347                 if (exclude_parent && parent_number != exclude_parent)
348                         continue;
349
350                 if (symbolic)
351                         name = xstrfmt("%s^%d", arg, parent_number);
352                 show_rev(include_parents ? NORMAL : REVERSED,
353                          parents->item->object.oid.hash, name);
354                 free(name);
355         }
356
357         *dotdot = '^';
358         return 1;
359 }
360
361 static int parseopt_dump(const struct option *o, const char *arg, int unset)
362 {
363         struct strbuf *parsed = o->value;
364         if (unset)
365                 strbuf_addf(parsed, " --no-%s", o->long_name);
366         else if (o->short_name && (o->long_name == NULL || !stuck_long))
367                 strbuf_addf(parsed, " -%c", o->short_name);
368         else
369                 strbuf_addf(parsed, " --%s", o->long_name);
370         if (arg) {
371                 if (!stuck_long)
372                         strbuf_addch(parsed, ' ');
373                 else if (o->long_name)
374                         strbuf_addch(parsed, '=');
375                 sq_quote_buf(parsed, arg);
376         }
377         return 0;
378 }
379
380 static const char *skipspaces(const char *s)
381 {
382         while (isspace(*s))
383                 s++;
384         return s;
385 }
386
387 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
388 {
389         static int keep_dashdash = 0, stop_at_non_option = 0;
390         static char const * const parseopt_usage[] = {
391                 N_("git rev-parse --parseopt [<options>] -- [<args>...]"),
392                 NULL
393         };
394         static struct option parseopt_opts[] = {
395                 OPT_BOOL(0, "keep-dashdash", &keep_dashdash,
396                                         N_("keep the `--` passed as an arg")),
397                 OPT_BOOL(0, "stop-at-non-option", &stop_at_non_option,
398                                         N_("stop parsing after the "
399                                            "first non-option argument")),
400                 OPT_BOOL(0, "stuck-long", &stuck_long,
401                                         N_("output in stuck long form")),
402                 OPT_END(),
403         };
404         static const char * const flag_chars = "*=?!";
405
406         struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
407         const char **usage = NULL;
408         struct option *opts = NULL;
409         int onb = 0, osz = 0, unb = 0, usz = 0;
410
411         strbuf_addstr(&parsed, "set --");
412         argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
413                              PARSE_OPT_KEEP_DASHDASH);
414         if (argc < 1 || strcmp(argv[0], "--"))
415                 usage_with_options(parseopt_usage, parseopt_opts);
416
417         /* get the usage up to the first line with a -- on it */
418         for (;;) {
419                 if (strbuf_getline(&sb, stdin) == EOF)
420                         die("premature end of input");
421                 ALLOC_GROW(usage, unb + 1, usz);
422                 if (!strcmp("--", sb.buf)) {
423                         if (unb < 1)
424                                 die("no usage string given before the `--' separator");
425                         usage[unb] = NULL;
426                         break;
427                 }
428                 usage[unb++] = strbuf_detach(&sb, NULL);
429         }
430
431         /* parse: (<short>|<short>,<long>|<long>)[*=?!]*<arghint>? SP+ <help> */
432         while (strbuf_getline(&sb, stdin) != EOF) {
433                 const char *s;
434                 const char *help;
435                 struct option *o;
436
437                 if (!sb.len)
438                         continue;
439
440                 ALLOC_GROW(opts, onb + 1, osz);
441                 memset(opts + onb, 0, sizeof(opts[onb]));
442
443                 o = &opts[onb++];
444                 help = strchr(sb.buf, ' ');
445                 if (!help || *sb.buf == ' ') {
446                         o->type = OPTION_GROUP;
447                         o->help = xstrdup(skipspaces(sb.buf));
448                         continue;
449                 }
450
451                 o->type = OPTION_CALLBACK;
452                 o->help = xstrdup(skipspaces(help));
453                 o->value = &parsed;
454                 o->flags = PARSE_OPT_NOARG;
455                 o->callback = &parseopt_dump;
456
457                 /* name(s) */
458                 s = strpbrk(sb.buf, flag_chars);
459                 if (s == NULL)
460                         s = help;
461
462                 if (s - sb.buf == 1) /* short option only */
463                         o->short_name = *sb.buf;
464                 else if (sb.buf[1] != ',') /* long option only */
465                         o->long_name = xmemdupz(sb.buf, s - sb.buf);
466                 else {
467                         o->short_name = *sb.buf;
468                         o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
469                 }
470
471                 /* flags */
472                 while (s < help) {
473                         switch (*s++) {
474                         case '=':
475                                 o->flags &= ~PARSE_OPT_NOARG;
476                                 continue;
477                         case '?':
478                                 o->flags &= ~PARSE_OPT_NOARG;
479                                 o->flags |= PARSE_OPT_OPTARG;
480                                 continue;
481                         case '!':
482                                 o->flags |= PARSE_OPT_NONEG;
483                                 continue;
484                         case '*':
485                                 o->flags |= PARSE_OPT_HIDDEN;
486                                 continue;
487                         }
488                         s--;
489                         break;
490                 }
491
492                 if (s < help)
493                         o->argh = xmemdupz(s, help - s);
494         }
495         strbuf_release(&sb);
496
497         /* put an OPT_END() */
498         ALLOC_GROW(opts, onb + 1, osz);
499         memset(opts + onb, 0, sizeof(opts[onb]));
500         argc = parse_options(argc, argv, prefix, opts, usage,
501                         (keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0) |
502                         (stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0) |
503                         PARSE_OPT_SHELL_EVAL);
504
505         strbuf_addstr(&parsed, " --");
506         sq_quote_argv(&parsed, argv, 0);
507         puts(parsed.buf);
508         return 0;
509 }
510
511 static int cmd_sq_quote(int argc, const char **argv)
512 {
513         struct strbuf buf = STRBUF_INIT;
514
515         if (argc)
516                 sq_quote_argv(&buf, argv, 0);
517         printf("%s\n", buf.buf);
518         strbuf_release(&buf);
519
520         return 0;
521 }
522
523 static void die_no_single_rev(int quiet)
524 {
525         if (quiet)
526                 exit(1);
527         else
528                 die("Needed a single revision");
529 }
530
531 static const char builtin_rev_parse_usage[] =
532 N_("git rev-parse --parseopt [<options>] -- [<args>...]\n"
533    "   or: git rev-parse --sq-quote [<arg>...]\n"
534    "   or: git rev-parse [<options>] [<arg>...]\n"
535    "\n"
536    "Run \"git rev-parse --parseopt -h\" for more information on the first usage.");
537
538 /*
539  * Parse "opt" or "opt=<value>", setting value respectively to either
540  * NULL or the string after "=".
541  */
542 static int opt_with_value(const char *arg, const char *opt, const char **value)
543 {
544         if (skip_prefix(arg, opt, &arg)) {
545                 if (!*arg) {
546                         *value = NULL;
547                         return 1;
548                 }
549                 if (*arg++ == '=') {
550                         *value = arg;
551                         return 1;
552                 }
553         }
554         return 0;
555 }
556
557 int cmd_rev_parse(int argc, const char **argv, const char *prefix)
558 {
559         int i, as_is = 0, verify = 0, quiet = 0, revs_count = 0, type = 0;
560         int did_repo_setup = 0;
561         int has_dashdash = 0;
562         int output_prefix = 0;
563         unsigned char sha1[20];
564         unsigned int flags = 0;
565         const char *name = NULL;
566         struct object_context unused;
567
568         if (argc > 1 && !strcmp("--parseopt", argv[1]))
569                 return cmd_parseopt(argc - 1, argv + 1, prefix);
570
571         if (argc > 1 && !strcmp("--sq-quote", argv[1]))
572                 return cmd_sq_quote(argc - 2, argv + 2);
573
574         if (argc > 1 && !strcmp("-h", argv[1]))
575                 usage(builtin_rev_parse_usage);
576
577         for (i = 1; i < argc; i++) {
578                 if (!strcmp(argv[i], "--")) {
579                         has_dashdash = 1;
580                         break;
581                 }
582         }
583
584         /* No options; just report on whether we're in a git repo or not. */
585         if (argc == 1) {
586                 setup_git_directory();
587                 git_config(git_default_config, NULL);
588                 return 0;
589         }
590
591         for (i = 1; i < argc; i++) {
592                 const char *arg = argv[i];
593
594                 if (!strcmp(arg, "--local-env-vars")) {
595                         int i;
596                         for (i = 0; local_repo_env[i]; i++)
597                                 printf("%s\n", local_repo_env[i]);
598                         continue;
599                 }
600                 if (!strcmp(arg, "--resolve-git-dir")) {
601                         const char *gitdir = argv[++i];
602                         if (!gitdir)
603                                 die("--resolve-git-dir requires an argument");
604                         gitdir = resolve_gitdir(gitdir);
605                         if (!gitdir)
606                                 die("not a gitdir '%s'", argv[i]);
607                         puts(gitdir);
608                         continue;
609                 }
610
611                 /* The rest of the options require a git repository. */
612                 if (!did_repo_setup) {
613                         prefix = setup_git_directory();
614                         git_config(git_default_config, NULL);
615                         did_repo_setup = 1;
616                 }
617
618                 if (!strcmp(arg, "--git-path")) {
619                         if (!argv[i + 1])
620                                 die("--git-path requires an argument");
621                         puts(git_path("%s", argv[i + 1]));
622                         i++;
623                         continue;
624                 }
625                 if (as_is) {
626                         if (show_file(arg, output_prefix) && as_is < 2)
627                                 verify_filename(prefix, arg, 0);
628                         continue;
629                 }
630                 if (!strcmp(arg,"-n")) {
631                         if (++i >= argc)
632                                 die("-n requires an argument");
633                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
634                                 show(arg);
635                                 show(argv[i]);
636                         }
637                         continue;
638                 }
639                 if (starts_with(arg, "-n")) {
640                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
641                                 show(arg);
642                         continue;
643                 }
644
645                 if (*arg == '-') {
646                         if (!strcmp(arg, "--")) {
647                                 as_is = 2;
648                                 /* Pass on the "--" if we show anything but files.. */
649                                 if (filter & (DO_FLAGS | DO_REVS))
650                                         show_file(arg, 0);
651                                 continue;
652                         }
653                         if (!strcmp(arg, "--default")) {
654                                 def = argv[++i];
655                                 if (!def)
656                                         die("--default requires an argument");
657                                 continue;
658                         }
659                         if (!strcmp(arg, "--prefix")) {
660                                 prefix = argv[++i];
661                                 if (!prefix)
662                                         die("--prefix requires an argument");
663                                 startup_info->prefix = prefix;
664                                 output_prefix = 1;
665                                 continue;
666                         }
667                         if (!strcmp(arg, "--revs-only")) {
668                                 filter &= ~DO_NOREV;
669                                 continue;
670                         }
671                         if (!strcmp(arg, "--no-revs")) {
672                                 filter &= ~DO_REVS;
673                                 continue;
674                         }
675                         if (!strcmp(arg, "--flags")) {
676                                 filter &= ~DO_NONFLAGS;
677                                 continue;
678                         }
679                         if (!strcmp(arg, "--no-flags")) {
680                                 filter &= ~DO_FLAGS;
681                                 continue;
682                         }
683                         if (!strcmp(arg, "--verify")) {
684                                 filter &= ~(DO_FLAGS|DO_NOREV);
685                                 verify = 1;
686                                 continue;
687                         }
688                         if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
689                                 quiet = 1;
690                                 flags |= GET_SHA1_QUIETLY;
691                                 continue;
692                         }
693                         if (opt_with_value(arg, "--short", &arg)) {
694                                 filter &= ~(DO_FLAGS|DO_NOREV);
695                                 verify = 1;
696                                 abbrev = DEFAULT_ABBREV;
697                                 if (!arg)
698                                         continue;
699                                 abbrev = strtoul(arg, NULL, 10);
700                                 if (abbrev < MINIMUM_ABBREV)
701                                         abbrev = MINIMUM_ABBREV;
702                                 else if (40 <= abbrev)
703                                         abbrev = 40;
704                                 continue;
705                         }
706                         if (!strcmp(arg, "--sq")) {
707                                 output_sq = 1;
708                                 continue;
709                         }
710                         if (!strcmp(arg, "--not")) {
711                                 show_type ^= REVERSED;
712                                 continue;
713                         }
714                         if (!strcmp(arg, "--symbolic")) {
715                                 symbolic = SHOW_SYMBOLIC_ASIS;
716                                 continue;
717                         }
718                         if (!strcmp(arg, "--symbolic-full-name")) {
719                                 symbolic = SHOW_SYMBOLIC_FULL;
720                                 continue;
721                         }
722                         if (opt_with_value(arg, "--abbrev-ref", &arg)) {
723                                 abbrev_ref = 1;
724                                 abbrev_ref_strict = warn_ambiguous_refs;
725                                 if (arg) {
726                                         if (!strcmp(arg, "strict"))
727                                                 abbrev_ref_strict = 1;
728                                         else if (!strcmp(arg, "loose"))
729                                                 abbrev_ref_strict = 0;
730                                         else
731                                                 die("unknown mode for --abbrev-ref: %s",
732                                                     arg);
733                                 }
734                                 continue;
735                         }
736                         if (!strcmp(arg, "--all")) {
737                                 for_each_ref(show_reference, NULL);
738                                 continue;
739                         }
740                         if (skip_prefix(arg, "--disambiguate=", &arg)) {
741                                 for_each_abbrev(arg, show_abbrev, NULL);
742                                 continue;
743                         }
744                         if (!strcmp(arg, "--bisect")) {
745                                 for_each_ref_in("refs/bisect/bad", show_reference, NULL);
746                                 for_each_ref_in("refs/bisect/good", anti_reference, NULL);
747                                 continue;
748                         }
749                         if (skip_prefix(arg, "--branches=", &arg)) {
750                                 for_each_glob_ref_in(show_reference, arg,
751                                         "refs/heads/", NULL);
752                                 clear_ref_exclusion(&ref_excludes);
753                                 continue;
754                         }
755                         if (!strcmp(arg, "--branches")) {
756                                 for_each_branch_ref(show_reference, NULL);
757                                 clear_ref_exclusion(&ref_excludes);
758                                 continue;
759                         }
760                         if (skip_prefix(arg, "--tags=", &arg)) {
761                                 for_each_glob_ref_in(show_reference, arg,
762                                         "refs/tags/", NULL);
763                                 clear_ref_exclusion(&ref_excludes);
764                                 continue;
765                         }
766                         if (!strcmp(arg, "--tags")) {
767                                 for_each_tag_ref(show_reference, NULL);
768                                 clear_ref_exclusion(&ref_excludes);
769                                 continue;
770                         }
771                         if (skip_prefix(arg, "--glob=", &arg)) {
772                                 for_each_glob_ref(show_reference, arg, NULL);
773                                 clear_ref_exclusion(&ref_excludes);
774                                 continue;
775                         }
776                         if (skip_prefix(arg, "--remotes=", &arg)) {
777                                 for_each_glob_ref_in(show_reference, arg,
778                                         "refs/remotes/", NULL);
779                                 clear_ref_exclusion(&ref_excludes);
780                                 continue;
781                         }
782                         if (!strcmp(arg, "--remotes")) {
783                                 for_each_remote_ref(show_reference, NULL);
784                                 clear_ref_exclusion(&ref_excludes);
785                                 continue;
786                         }
787                         if (skip_prefix(arg, "--exclude=", &arg)) {
788                                 add_ref_exclusion(&ref_excludes, arg);
789                                 continue;
790                         }
791                         if (!strcmp(arg, "--show-toplevel")) {
792                                 const char *work_tree = get_git_work_tree();
793                                 if (work_tree)
794                                         puts(work_tree);
795                                 continue;
796                         }
797                         if (!strcmp(arg, "--show-prefix")) {
798                                 if (prefix)
799                                         puts(prefix);
800                                 else
801                                         putchar('\n');
802                                 continue;
803                         }
804                         if (!strcmp(arg, "--show-cdup")) {
805                                 const char *pfx = prefix;
806                                 if (!is_inside_work_tree()) {
807                                         const char *work_tree =
808                                                 get_git_work_tree();
809                                         if (work_tree)
810                                                 printf("%s\n", work_tree);
811                                         continue;
812                                 }
813                                 while (pfx) {
814                                         pfx = strchr(pfx, '/');
815                                         if (pfx) {
816                                                 pfx++;
817                                                 printf("../");
818                                         }
819                                 }
820                                 putchar('\n');
821                                 continue;
822                         }
823                         if (!strcmp(arg, "--git-dir")) {
824                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
825                                 char *cwd;
826                                 int len;
827                                 if (gitdir) {
828                                         puts(gitdir);
829                                         continue;
830                                 }
831                                 if (!prefix) {
832                                         puts(".git");
833                                         continue;
834                                 }
835                                 cwd = xgetcwd();
836                                 len = strlen(cwd);
837                                 printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
838                                 free(cwd);
839                                 continue;
840                         }
841                         if (!strcmp(arg, "--git-common-dir")) {
842                                 const char *pfx = prefix ? prefix : "";
843                                 puts(prefix_filename(pfx, strlen(pfx), get_git_common_dir()));
844                                 continue;
845                         }
846                         if (!strcmp(arg, "--is-inside-git-dir")) {
847                                 printf("%s\n", is_inside_git_dir() ? "true"
848                                                 : "false");
849                                 continue;
850                         }
851                         if (!strcmp(arg, "--is-inside-work-tree")) {
852                                 printf("%s\n", is_inside_work_tree() ? "true"
853                                                 : "false");
854                                 continue;
855                         }
856                         if (!strcmp(arg, "--is-bare-repository")) {
857                                 printf("%s\n", is_bare_repository() ? "true"
858                                                 : "false");
859                                 continue;
860                         }
861                         if (!strcmp(arg, "--shared-index-path")) {
862                                 if (read_cache() < 0)
863                                         die(_("Could not read the index"));
864                                 if (the_index.split_index) {
865                                         const unsigned char *sha1 = the_index.split_index->base_sha1;
866                                         puts(git_path("sharedindex.%s", sha1_to_hex(sha1)));
867                                 }
868                                 continue;
869                         }
870                         if (skip_prefix(arg, "--since=", &arg)) {
871                                 show_datestring("--max-age=", arg);
872                                 continue;
873                         }
874                         if (skip_prefix(arg, "--after=", &arg)) {
875                                 show_datestring("--max-age=", arg);
876                                 continue;
877                         }
878                         if (skip_prefix(arg, "--before=", &arg)) {
879                                 show_datestring("--min-age=", arg);
880                                 continue;
881                         }
882                         if (skip_prefix(arg, "--until=", &arg)) {
883                                 show_datestring("--min-age=", arg);
884                                 continue;
885                         }
886                         if (show_flag(arg) && verify)
887                                 die_no_single_rev(quiet);
888                         continue;
889                 }
890
891                 /* Not a flag argument */
892                 if (try_difference(arg))
893                         continue;
894                 if (try_parent_shorthands(arg))
895                         continue;
896                 name = arg;
897                 type = NORMAL;
898                 if (*arg == '^') {
899                         name++;
900                         type = REVERSED;
901                 }
902                 if (!get_sha1_with_context(name, flags, sha1, &unused)) {
903                         if (verify)
904                                 revs_count++;
905                         else
906                                 show_rev(type, sha1, name);
907                         continue;
908                 }
909                 if (verify)
910                         die_no_single_rev(quiet);
911                 if (has_dashdash)
912                         die("bad revision '%s'", arg);
913                 as_is = 1;
914                 if (!show_file(arg, output_prefix))
915                         continue;
916                 verify_filename(prefix, arg, 1);
917         }
918         if (verify) {
919                 if (revs_count == 1) {
920                         show_rev(type, sha1, name);
921                         return 0;
922                 } else if (revs_count == 0 && show_default())
923                         return 0;
924                 die_no_single_rev(quiet);
925         } else
926                 show_default();
927         return 0;
928 }