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#define DO_REVS 1
17#define DO_NOREV 2
18#define DO_FLAGS 4
19#define DO_NONFLAGS 8
20static int filter = ~0;
21static const char *def;
23#define NORMAL 0
25#define REVERSED 1
26static int show_type = NORMAL;
27#define SHOW_SYMBOLIC_ASIS 1
29#define SHOW_SYMBOLIC_FULL 2
30static int symbolic;
31static int abbrev;
32static int abbrev_ref;
33static int abbrev_ref_strict;
34static int output_sq;
35static int stuck_long;
37static struct string_list *ref_excludes;
38/*
40 * Some arguments are relevant "revision" arguments,
41 * others are about output format or other details.
42 * This sorts it all out.
43 */
44static 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 /* accept -<digit>, like traditional "head" */
80 if ((*arg == '-') && isdigit(arg[1]))
81 return 1;
82 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/* Output argument as a string, either SQ or normal */
96static void show(const char *arg)
97{
98 if (output_sq) {
99 int sq = '\'', ch;
100 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/* Like show(), but with a negation prefix according to type */
115static void show_with_type(int type, const char *arg)
116{
117 if (type != show_type)
118 putchar('^');
119 show(arg);
120}
121/* Output a revision, only if filter allows it */
123static void show_rev(int type, const unsigned char *sha1, const char *name)
124{
125 if (!(filter & DO_REVS))
126 return;
127 def = NULL;
128 if ((symbolic || abbrev_ref) && name) {
130 if (symbolic == SHOW_SYMBOLIC_FULL || abbrev_ref) {
131 unsigned char discard[20];
132 char *full;
133 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/* Output a flag, only if filter allows it. */
166static 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}
176static int show_default(void)
178{
179 const char *s = def;
180 if (s) {
182 unsigned char sha1[20];
183 def = NULL;
185 if (!get_sha1(s, sha1)) {
186 show_rev(NORMAL, sha1, s);
187 return 1;
188 }
189 }
190 return 0;
191}
192static int show_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
194{
195 if (ref_excluded(ref_excludes, refname))
196 return 0;
197 show_rev(NORMAL, sha1, refname);
198 return 0;
199}
200static int anti_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
202{
203 show_rev(REVERSED, sha1, refname);
204 return 0;
205}
206static int show_abbrev(const unsigned char *sha1, void *cb_data)
208{
209 show_rev(NORMAL, sha1, NULL);
210 return 0;
211}
212static void show_datestring(const char *flag, const char *datestr)
214{
215 static char buffer[100];
216 /* 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}
223static 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}
239static 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 if (!(dotdot = strstr(arg, "..")))
251 return 0;
252 next = dotdot + 2;
253 this = arg;
254 symmetric = (*next == '.');
255 *dotdot = 0;
257 next += symmetric;
258 if (!*next)
260 next = head_by_default;
261 if (dotdot == arg)
262 this = head_by_default;
263 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 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}
297static 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 if ((dotdot = strstr(arg, "^!")))
307 parents_only = 0;
308 else if ((dotdot = strstr(arg, "^@")))
309 parents_only = 1;
310 if (!dotdot || dotdot[2])
312 return 0;
313 *dotdot = 0;
315 if (get_sha1_committish(arg, sha1)) {
316 *dotdot = '^';
317 return 0;
318 }
319 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 *dotdot = '^';
328 return 1;
329}
330static 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}
349static const char *skipspaces(const char *s)
351{
352 while (isspace(*s))
353 s++;
354 return s;
355}
356static 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 struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
376 const char **usage = NULL;
377 struct option *opts = NULL;
378 int onb = 0, osz = 0, unb = 0, usz = 0;
379 strbuf_addstr(&parsed, "set --");
381 argc = parse_options(argc, argv, prefix, parseopt_opts, parseopt_usage,
382 PARSE_OPT_KEEP_DASHDASH);
383 if (argc < 1 || strcmp(argv[0], "--"))
384 usage_with_options(parseopt_usage, parseopt_opts);
385 /* get the usage up to the first line with a -- on it */
387 for (;;) {
388 if (strbuf_getline(&sb, stdin, '\n') == EOF)
389 die("premature end of input");
390 ALLOC_GROW(usage, unb + 1, usz);
391 if (!strcmp("--", sb.buf)) {
392 if (unb < 1)
393 die("no usage string given before the `--' separator");
394 usage[unb] = NULL;
395 break;
396 }
397 usage[unb++] = strbuf_detach(&sb, NULL);
398 }
399 /* parse: (<short>|<short>,<long>|<long>)[*=?!]*<arghint>? SP+ <help> */
401 while (strbuf_getline(&sb, stdin, '\n') != EOF) {
402 const char *s;
403 const char *end;
404 struct option *o;
405 if (!sb.len)
407 continue;
408 ALLOC_GROW(opts, onb + 1, osz);
410 memset(opts + onb, 0, sizeof(opts[onb]));
411 o = &opts[onb++];
413 s = strchr(sb.buf, ' ');
414 if (!s || *sb.buf == ' ') {
415 o->type = OPTION_GROUP;
416 o->help = xstrdup(skipspaces(sb.buf));
417 continue;
418 }
419 o->type = OPTION_CALLBACK;
421 o->help = xstrdup(skipspaces(s));
422 o->value = &parsed;
423 o->flags = PARSE_OPT_NOARG;
424 o->callback = &parseopt_dump;
425 /* Possible argument name hint */
427 end = s;
428 while (s > sb.buf && strchr("*=?!", s[-1]) == NULL)
429 --s;
430 if (s != sb.buf && s != end)
431 o->argh = xmemdupz(s, end - s);
432 if (s == sb.buf)
433 s = end;
434 while (s > sb.buf && strchr("*=?!", s[-1])) {
436 switch (*--s) {
437 case '=':
438 o->flags &= ~PARSE_OPT_NOARG;
439 break;
440 case '?':
441 o->flags &= ~PARSE_OPT_NOARG;
442 o->flags |= PARSE_OPT_OPTARG;
443 break;
444 case '!':
445 o->flags |= PARSE_OPT_NONEG;
446 break;
447 case '*':
448 o->flags |= PARSE_OPT_HIDDEN;
449 break;
450 }
451 }
452 if (s - sb.buf == 1) /* short option only */
454 o->short_name = *sb.buf;
455 else if (sb.buf[1] != ',') /* long option only */
456 o->long_name = xmemdupz(sb.buf, s - sb.buf);
457 else {
458 o->short_name = *sb.buf;
459 o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
460 }
461 }
462 strbuf_release(&sb);
463 /* 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 strbuf_addf(&parsed, " --");
473 sq_quote_argv(&parsed, argv, 0);
474 puts(parsed.buf);
475 return 0;
476}
477static int cmd_sq_quote(int argc, const char **argv)
479{
480 struct strbuf buf = STRBUF_INIT;
481 if (argc)
483 sq_quote_argv(&buf, argv, 0);
484 printf("%s\n", buf.buf);
485 strbuf_release(&buf);
486 return 0;
488}
489static void die_no_single_rev(int quiet)
491{
492 if (quiet)
493 exit(1);
494 else
495 die("Needed a single revision");
496}
497static const char builtin_rev_parse_usage[] =
499N_("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.");
504int 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 if (argc > 1 && !strcmp("--parseopt", argv[1]))
516 return cmd_parseopt(argc - 1, argv + 1, prefix);
517 if (argc > 1 && !strcmp("--sq-quote", argv[1]))
519 return cmd_sq_quote(argc - 2, argv + 2);
520 if (argc > 1 && !strcmp("-h", argv[1]))
522 usage(builtin_rev_parse_usage);
523 for (i = 1; i < argc; i++) {
525 if (!strcmp(argv[i], "--")) {
526 has_dashdash = 1;
527 break;
528 }
529 }
530 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 if (as_is) {
537 if (show_file(arg, output_prefix) && as_is < 2)
538 verify_filename(prefix, arg, 0);
539 continue;
540 }
541 if (!strcmp(arg,"-n")) {
542 if (++i >= argc)
543 die("-n requires an argument");
544 if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
545 show(arg);
546 show(argv[i]);
547 }
548 continue;
549 }
550 if (starts_with(arg, "-n")) {
551 if ((filter & DO_FLAGS) && (filter & DO_REVS))
552 show(arg);
553 continue;
554 }
555 if (*arg == '-') {
557 if (!strcmp(arg, "--")) {
558 as_is = 2;
559 /* Pass on the "--" if we show anything but files.. */
560 if (filter & (DO_FLAGS | DO_REVS))
561 show_file(arg, 0);
562 continue;
563 }
564 if (!strcmp(arg, "--default")) {
565 def = argv[++i];
566 if (!def)
567 die("--default requires an argument");
568 continue;
569 }
570 if (!strcmp(arg, "--prefix")) {
571 prefix = argv[++i];
572 if (!prefix)
573 die("--prefix requires an argument");
574 startup_info->prefix = prefix;
575 output_prefix = 1;
576 continue;
577 }
578 if (!strcmp(arg, "--revs-only")) {
579 filter &= ~DO_NOREV;
580 continue;
581 }
582 if (!strcmp(arg, "--no-revs")) {
583 filter &= ~DO_REVS;
584 continue;
585 }
586 if (!strcmp(arg, "--flags")) {
587 filter &= ~DO_NONFLAGS;
588 continue;
589 }
590 if (!strcmp(arg, "--no-flags")) {
591 filter &= ~DO_FLAGS;
592 continue;
593 }
594 if (!strcmp(arg, "--verify")) {
595 filter &= ~(DO_FLAGS|DO_NOREV);
596 verify = 1;
597 continue;
598 }
599 if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
600 quiet = 1;
601 flags |= GET_SHA1_QUIETLY;
602 continue;
603 }
604 if (!strcmp(arg, "--short") ||
605 starts_with(arg, "--short=")) {
606 filter &= ~(DO_FLAGS|DO_NOREV);
607 verify = 1;
608 abbrev = DEFAULT_ABBREV;
609 if (arg[7] == '=')
610 abbrev = strtoul(arg + 8, NULL, 10);
611 if (abbrev < MINIMUM_ABBREV)
612 abbrev = MINIMUM_ABBREV;
613 else if (40 <= abbrev)
614 abbrev = 40;
615 continue;
616 }
617 if (!strcmp(arg, "--sq")) {
618 output_sq = 1;
619 continue;
620 }
621 if (!strcmp(arg, "--not")) {
622 show_type ^= REVERSED;
623 continue;
624 }
625 if (!strcmp(arg, "--symbolic")) {
626 symbolic = SHOW_SYMBOLIC_ASIS;
627 continue;
628 }
629 if (!strcmp(arg, "--symbolic-full-name")) {
630 symbolic = SHOW_SYMBOLIC_FULL;
631 continue;
632 }
633 if (starts_with(arg, "--abbrev-ref") &&
634 (!arg[12] || arg[12] == '=')) {
635 abbrev_ref = 1;
636 abbrev_ref_strict = warn_ambiguous_refs;
637 if (arg[12] == '=') {
638 if (!strcmp(arg + 13, "strict"))
639 abbrev_ref_strict = 1;
640 else if (!strcmp(arg + 13, "loose"))
641 abbrev_ref_strict = 0;
642 else
643 die("unknown mode for %s", arg);
644 }
645 continue;
646 }
647 if (!strcmp(arg, "--all")) {
648 for_each_ref(show_reference, NULL);
649 continue;
650 }
651 if (starts_with(arg, "--disambiguate=")) {
652 for_each_abbrev(arg + 15, show_abbrev, NULL);
653 continue;
654 }
655 if (!strcmp(arg, "--bisect")) {
656 for_each_ref_in("refs/bisect/bad", show_reference, NULL);
657 for_each_ref_in("refs/bisect/good", anti_reference, NULL);
658 continue;
659 }
660 if (starts_with(arg, "--branches=")) {
661 for_each_glob_ref_in(show_reference, arg + 11,
662 "refs/heads/", NULL);
663 clear_ref_exclusion(&ref_excludes);
664 continue;
665 }
666 if (!strcmp(arg, "--branches")) {
667 for_each_branch_ref(show_reference, NULL);
668 clear_ref_exclusion(&ref_excludes);
669 continue;
670 }
671 if (starts_with(arg, "--tags=")) {
672 for_each_glob_ref_in(show_reference, arg + 7,
673 "refs/tags/", NULL);
674 clear_ref_exclusion(&ref_excludes);
675 continue;
676 }
677 if (!strcmp(arg, "--tags")) {
678 for_each_tag_ref(show_reference, NULL);
679 clear_ref_exclusion(&ref_excludes);
680 continue;
681 }
682 if (starts_with(arg, "--glob=")) {
683 for_each_glob_ref(show_reference, arg + 7, NULL);
684 clear_ref_exclusion(&ref_excludes);
685 continue;
686 }
687 if (starts_with(arg, "--remotes=")) {
688 for_each_glob_ref_in(show_reference, arg + 10,
689 "refs/remotes/", NULL);
690 clear_ref_exclusion(&ref_excludes);
691 continue;
692 }
693 if (!strcmp(arg, "--remotes")) {
694 for_each_remote_ref(show_reference, NULL);
695 clear_ref_exclusion(&ref_excludes);
696 continue;
697 }
698 if (starts_with(arg, "--exclude=")) {
699 add_ref_exclusion(&ref_excludes, arg + 10);
700 continue;
701 }
702 if (!strcmp(arg, "--local-env-vars")) {
703 int i;
704 for (i = 0; local_repo_env[i]; i++)
705 printf("%s\n", local_repo_env[i]);
706 continue;
707 }
708 if (!strcmp(arg, "--show-toplevel")) {
709 const char *work_tree = get_git_work_tree();
710 if (work_tree)
711 puts(work_tree);
712 continue;
713 }
714 if (!strcmp(arg, "--show-prefix")) {
715 if (prefix)
716 puts(prefix);
717 else
718 putchar('\n');
719 continue;
720 }
721 if (!strcmp(arg, "--show-cdup")) {
722 const char *pfx = prefix;
723 if (!is_inside_work_tree()) {
724 const char *work_tree =
725 get_git_work_tree();
726 if (work_tree)
727 printf("%s\n", work_tree);
728 continue;
729 }
730 while (pfx) {
731 pfx = strchr(pfx, '/');
732 if (pfx) {
733 pfx++;
734 printf("../");
735 }
736 }
737 putchar('\n');
738 continue;
739 }
740 if (!strcmp(arg, "--git-dir")) {
741 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
742 char *cwd;
743 int len;
744 if (gitdir) {
745 puts(gitdir);
746 continue;
747 }
748 if (!prefix) {
749 puts(".git");
750 continue;
751 }
752 cwd = xgetcwd();
753 len = strlen(cwd);
754 printf("%s%s.git\n", cwd, len && cwd[len-1] != '/' ? "/" : "");
755 free(cwd);
756 continue;
757 }
758 if (!strcmp(arg, "--resolve-git-dir")) {
759 const char *gitdir = argv[++i];
760 if (!gitdir)
761 die("--resolve-git-dir requires an argument");
762 gitdir = resolve_gitdir(gitdir);
763 if (!gitdir)
764 die("not a gitdir '%s'", argv[i]);
765 puts(gitdir);
766 continue;
767 }
768 if (!strcmp(arg, "--is-inside-git-dir")) {
769 printf("%s\n", is_inside_git_dir() ? "true"
770 : "false");
771 continue;
772 }
773 if (!strcmp(arg, "--is-inside-work-tree")) {
774 printf("%s\n", is_inside_work_tree() ? "true"
775 : "false");
776 continue;
777 }
778 if (!strcmp(arg, "--is-bare-repository")) {
779 printf("%s\n", is_bare_repository() ? "true"
780 : "false");
781 continue;
782 }
783 if (!strcmp(arg, "--shared-index-path")) {
784 if (read_cache() < 0)
785 die(_("Could not read the index"));
786 if (the_index.split_index) {
787 const unsigned char *sha1 = the_index.split_index->base_sha1;
788 puts(git_path("sharedindex.%s", sha1_to_hex(sha1)));
789 }
790 continue;
791 }
792 if (starts_with(arg, "--since=")) {
793 show_datestring("--max-age=", arg+8);
794 continue;
795 }
796 if (starts_with(arg, "--after=")) {
797 show_datestring("--max-age=", arg+8);
798 continue;
799 }
800 if (starts_with(arg, "--before=")) {
801 show_datestring("--min-age=", arg+9);
802 continue;
803 }
804 if (starts_with(arg, "--until=")) {
805 show_datestring("--min-age=", arg+8);
806 continue;
807 }
808 if (show_flag(arg) && verify)
809 die_no_single_rev(quiet);
810 continue;
811 }
812 /* Not a flag argument */
814 if (try_difference(arg))
815 continue;
816 if (try_parent_shorthands(arg))
817 continue;
818 name = arg;
819 type = NORMAL;
820 if (*arg == '^') {
821 name++;
822 type = REVERSED;
823 }
824 if (!get_sha1_with_context(name, flags, sha1, &unused)) {
825 if (verify)
826 revs_count++;
827 else
828 show_rev(type, sha1, name);
829 continue;
830 }
831 if (verify)
832 die_no_single_rev(quiet);
833 if (has_dashdash)
834 die("bad revision '%s'", arg);
835 as_is = 1;
836 if (!show_file(arg, output_prefix))
837 continue;
838 verify_filename(prefix, arg, 1);
839 }
840 if (verify) {
841 if (revs_count == 1) {
842 show_rev(type, sha1, name);
843 return 0;
844 } else if (revs_count == 0 && show_default())
845 return 0;
846 die_no_single_rev(quiet);
847 } else
848 show_default();
849 return 0;
850}