fast-import: Don't use a maybe-clobbered errno value
[git] / builtin-rev-parse.c
1 /*
2  * rev-parse.c
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  */
6 #include "cache.h"
7 #include "commit.h"
8 #include "refs.h"
9 #include "quote.h"
10 #include "builtin.h"
11 #include "parse-options.h"
12
13 #define DO_REVS         1
14 #define DO_NOREV        2
15 #define DO_FLAGS        4
16 #define DO_NONFLAGS     8
17 static int filter = ~0;
18
19 static const char *def;
20
21 #define NORMAL 0
22 #define REVERSED 1
23 static int show_type = NORMAL;
24
25 #define SHOW_SYMBOLIC_ASIS 1
26 #define SHOW_SYMBOLIC_FULL 2
27 static int symbolic;
28 static int abbrev;
29 static int output_sq;
30
31 static int revs_count;
32
33 /*
34  * Some arguments are relevant "revision" arguments,
35  * others are about output format or other details.
36  * This sorts it all out.
37  */
38 static int is_rev_argument(const char *arg)
39 {
40         static const char *rev_args[] = {
41                 "--all",
42                 "--bisect",
43                 "--dense",
44                 "--branches",
45                 "--header",
46                 "--max-age=",
47                 "--max-count=",
48                 "--min-age=",
49                 "--no-merges",
50                 "--objects",
51                 "--objects-edge",
52                 "--parents",
53                 "--pretty",
54                 "--remotes",
55                 "--sparse",
56                 "--tags",
57                 "--topo-order",
58                 "--date-order",
59                 "--unpacked",
60                 NULL
61         };
62         const char **p = rev_args;
63
64         /* accept -<digit>, like traditional "head" */
65         if ((*arg == '-') && isdigit(arg[1]))
66                 return 1;
67
68         for (;;) {
69                 const char *str = *p++;
70                 int len;
71                 if (!str)
72                         return 0;
73                 len = strlen(str);
74                 if (!strcmp(arg, str) ||
75                     (str[len-1] == '=' && !strncmp(arg, str, len)))
76                         return 1;
77         }
78 }
79
80 /* Output argument as a string, either SQ or normal */
81 static void show(const char *arg)
82 {
83         if (output_sq) {
84                 int sq = '\'', ch;
85
86                 putchar(sq);
87                 while ((ch = *arg++)) {
88                         if (ch == sq)
89                                 fputs("'\\'", stdout);
90                         putchar(ch);
91                 }
92                 putchar(sq);
93                 putchar(' ');
94         }
95         else
96                 puts(arg);
97 }
98
99 /* Output a revision, only if filter allows it */
100 static void show_rev(int type, const unsigned char *sha1, const char *name)
101 {
102         if (!(filter & DO_REVS))
103                 return;
104         def = NULL;
105         revs_count++;
106
107         if (type != show_type)
108                 putchar('^');
109         if (symbolic && name) {
110                 if (symbolic == SHOW_SYMBOLIC_FULL) {
111                         unsigned char discard[20];
112                         char *full;
113
114                         switch (dwim_ref(name, strlen(name), discard, &full)) {
115                         case 0:
116                                 /*
117                                  * Not found -- not a ref.  We could
118                                  * emit "name" here, but symbolic-full
119                                  * users are interested in finding the
120                                  * refs spelled in full, and they would
121                                  * need to filter non-refs if we did so.
122                                  */
123                                 break;
124                         case 1: /* happy */
125                                 show(full);
126                                 break;
127                         default: /* ambiguous */
128                                 error("refname '%s' is ambiguous", name);
129                                 break;
130                         }
131                 } else {
132                         show(name);
133                 }
134         }
135         else if (abbrev)
136                 show(find_unique_abbrev(sha1, abbrev));
137         else
138                 show(sha1_to_hex(sha1));
139 }
140
141 /* Output a flag, only if filter allows it. */
142 static int show_flag(const char *arg)
143 {
144         if (!(filter & DO_FLAGS))
145                 return 0;
146         if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
147                 show(arg);
148                 return 1;
149         }
150         return 0;
151 }
152
153 static void show_default(void)
154 {
155         const char *s = def;
156
157         if (s) {
158                 unsigned char sha1[20];
159
160                 def = NULL;
161                 if (!get_sha1(s, sha1)) {
162                         show_rev(NORMAL, sha1, s);
163                         return;
164                 }
165         }
166 }
167
168 static int show_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
169 {
170         show_rev(NORMAL, sha1, refname);
171         return 0;
172 }
173
174 static void show_datestring(const char *flag, const char *datestr)
175 {
176         static char buffer[100];
177
178         /* date handling requires both flags and revs */
179         if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
180                 return;
181         snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
182         show(buffer);
183 }
184
185 static int show_file(const char *arg)
186 {
187         show_default();
188         if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
189                 show(arg);
190                 return 1;
191         }
192         return 0;
193 }
194
195 static int try_difference(const char *arg)
196 {
197         char *dotdot;
198         unsigned char sha1[20];
199         unsigned char end[20];
200         const char *next;
201         const char *this;
202         int symmetric;
203
204         if (!(dotdot = strstr(arg, "..")))
205                 return 0;
206         next = dotdot + 2;
207         this = arg;
208         symmetric = (*next == '.');
209
210         *dotdot = 0;
211         next += symmetric;
212
213         if (!*next)
214                 next = "HEAD";
215         if (dotdot == arg)
216                 this = "HEAD";
217         if (!get_sha1(this, sha1) && !get_sha1(next, end)) {
218                 show_rev(NORMAL, end, next);
219                 show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
220                 if (symmetric) {
221                         struct commit_list *exclude;
222                         struct commit *a, *b;
223                         a = lookup_commit_reference(sha1);
224                         b = lookup_commit_reference(end);
225                         exclude = get_merge_bases(a, b, 1);
226                         while (exclude) {
227                                 struct commit_list *n = exclude->next;
228                                 show_rev(REVERSED,
229                                          exclude->item->object.sha1,NULL);
230                                 free(exclude);
231                                 exclude = n;
232                         }
233                 }
234                 return 1;
235         }
236         *dotdot = '.';
237         return 0;
238 }
239
240 static int parseopt_dump(const struct option *o, const char *arg, int unset)
241 {
242         struct strbuf *parsed = o->value;
243         if (unset)
244                 strbuf_addf(parsed, " --no-%s", o->long_name);
245         else if (o->short_name)
246                 strbuf_addf(parsed, " -%c", o->short_name);
247         else
248                 strbuf_addf(parsed, " --%s", o->long_name);
249         if (arg) {
250                 strbuf_addch(parsed, ' ');
251                 sq_quote_buf(parsed, arg);
252         }
253         return 0;
254 }
255
256 static const char *skipspaces(const char *s)
257 {
258         while (isspace(*s))
259                 s++;
260         return s;
261 }
262
263 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
264 {
265         static int keep_dashdash = 0;
266         static char const * const parseopt_usage[] = {
267                 "git-rev-parse --parseopt [options] -- [<args>...]",
268                 NULL
269         };
270         static struct option parseopt_opts[] = {
271                 OPT_BOOLEAN(0, "keep-dashdash", &keep_dashdash,
272                                         "keep the `--` passed as an arg"),
273                 OPT_END(),
274         };
275
276         struct strbuf sb, parsed;
277         const char **usage = NULL;
278         struct option *opts = NULL;
279         int onb = 0, osz = 0, unb = 0, usz = 0;
280
281         strbuf_init(&parsed, 0);
282         strbuf_addstr(&parsed, "set --");
283         argc = parse_options(argc, argv, parseopt_opts, parseopt_usage,
284                              PARSE_OPT_KEEP_DASHDASH);
285         if (argc < 1 || strcmp(argv[0], "--"))
286                 usage_with_options(parseopt_usage, parseopt_opts);
287
288         strbuf_init(&sb, 0);
289         /* get the usage up to the first line with a -- on it */
290         for (;;) {
291                 if (strbuf_getline(&sb, stdin, '\n') == EOF)
292                         die("premature end of input");
293                 ALLOC_GROW(usage, unb + 1, usz);
294                 if (!strcmp("--", sb.buf)) {
295                         if (unb < 1)
296                                 die("no usage string given before the `--' separator");
297                         usage[unb] = NULL;
298                         break;
299                 }
300                 usage[unb++] = strbuf_detach(&sb, NULL);
301         }
302
303         /* parse: (<short>|<short>,<long>|<long>)[=?]? SP+ <help> */
304         while (strbuf_getline(&sb, stdin, '\n') != EOF) {
305                 const char *s;
306                 struct option *o;
307
308                 if (!sb.len)
309                         continue;
310
311                 ALLOC_GROW(opts, onb + 1, osz);
312                 memset(opts + onb, 0, sizeof(opts[onb]));
313
314                 o = &opts[onb++];
315                 s = strchr(sb.buf, ' ');
316                 if (!s || *sb.buf == ' ') {
317                         o->type = OPTION_GROUP;
318                         o->help = xstrdup(skipspaces(s));
319                         continue;
320                 }
321
322                 o->type = OPTION_CALLBACK;
323                 o->help = xstrdup(skipspaces(s));
324                 o->value = &parsed;
325                 o->callback = &parseopt_dump;
326                 switch (s[-1]) {
327                 case '=':
328                         s--;
329                         break;
330                 case '?':
331                         o->flags = PARSE_OPT_OPTARG;
332                         s--;
333                         break;
334                 default:
335                         o->flags = PARSE_OPT_NOARG;
336                         break;
337                 }
338
339                 if (s - sb.buf == 1) /* short option only */
340                         o->short_name = *sb.buf;
341                 else if (sb.buf[1] != ',') /* long option only */
342                         o->long_name = xmemdupz(sb.buf, s - sb.buf);
343                 else {
344                         o->short_name = *sb.buf;
345                         o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
346                 }
347         }
348         strbuf_release(&sb);
349
350         /* put an OPT_END() */
351         ALLOC_GROW(opts, onb + 1, osz);
352         memset(opts + onb, 0, sizeof(opts[onb]));
353         argc = parse_options(argc, argv, opts, usage,
354                              keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0);
355
356         strbuf_addf(&parsed, " --");
357         sq_quote_argv(&parsed, argv, 0);
358         puts(parsed.buf);
359         return 0;
360 }
361
362 int cmd_rev_parse(int argc, const char **argv, const char *prefix)
363 {
364         int i, as_is = 0, verify = 0;
365         unsigned char sha1[20];
366
367         if (argc > 1 && !strcmp("--parseopt", argv[1]))
368                 return cmd_parseopt(argc - 1, argv + 1, prefix);
369
370         prefix = setup_git_directory();
371         git_config(git_default_config);
372         for (i = 1; i < argc; i++) {
373                 const char *arg = argv[i];
374
375                 if (as_is) {
376                         if (show_file(arg) && as_is < 2)
377                                 verify_filename(prefix, arg);
378                         continue;
379                 }
380                 if (!strcmp(arg,"-n")) {
381                         if (++i >= argc)
382                                 die("-n requires an argument");
383                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
384                                 show(arg);
385                                 show(argv[i]);
386                         }
387                         continue;
388                 }
389                 if (!prefixcmp(arg, "-n")) {
390                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
391                                 show(arg);
392                         continue;
393                 }
394
395                 if (*arg == '-') {
396                         if (!strcmp(arg, "--")) {
397                                 as_is = 2;
398                                 /* Pass on the "--" if we show anything but files.. */
399                                 if (filter & (DO_FLAGS | DO_REVS))
400                                         show_file(arg);
401                                 continue;
402                         }
403                         if (!strcmp(arg, "--default")) {
404                                 def = argv[i+1];
405                                 i++;
406                                 continue;
407                         }
408                         if (!strcmp(arg, "--revs-only")) {
409                                 filter &= ~DO_NOREV;
410                                 continue;
411                         }
412                         if (!strcmp(arg, "--no-revs")) {
413                                 filter &= ~DO_REVS;
414                                 continue;
415                         }
416                         if (!strcmp(arg, "--flags")) {
417                                 filter &= ~DO_NONFLAGS;
418                                 continue;
419                         }
420                         if (!strcmp(arg, "--no-flags")) {
421                                 filter &= ~DO_FLAGS;
422                                 continue;
423                         }
424                         if (!strcmp(arg, "--verify")) {
425                                 filter &= ~(DO_FLAGS|DO_NOREV);
426                                 verify = 1;
427                                 continue;
428                         }
429                         if (!strcmp(arg, "--short") ||
430                             !prefixcmp(arg, "--short=")) {
431                                 filter &= ~(DO_FLAGS|DO_NOREV);
432                                 verify = 1;
433                                 abbrev = DEFAULT_ABBREV;
434                                 if (arg[7] == '=')
435                                         abbrev = strtoul(arg + 8, NULL, 10);
436                                 if (abbrev < MINIMUM_ABBREV)
437                                         abbrev = MINIMUM_ABBREV;
438                                 else if (40 <= abbrev)
439                                         abbrev = 40;
440                                 continue;
441                         }
442                         if (!strcmp(arg, "--sq")) {
443                                 output_sq = 1;
444                                 continue;
445                         }
446                         if (!strcmp(arg, "--not")) {
447                                 show_type ^= REVERSED;
448                                 continue;
449                         }
450                         if (!strcmp(arg, "--symbolic")) {
451                                 symbolic = SHOW_SYMBOLIC_ASIS;
452                                 continue;
453                         }
454                         if (!strcmp(arg, "--symbolic-full-name")) {
455                                 symbolic = SHOW_SYMBOLIC_FULL;
456                                 continue;
457                         }
458                         if (!strcmp(arg, "--all")) {
459                                 for_each_ref(show_reference, NULL);
460                                 continue;
461                         }
462                         if (!strcmp(arg, "--branches")) {
463                                 for_each_branch_ref(show_reference, NULL);
464                                 continue;
465                         }
466                         if (!strcmp(arg, "--tags")) {
467                                 for_each_tag_ref(show_reference, NULL);
468                                 continue;
469                         }
470                         if (!strcmp(arg, "--remotes")) {
471                                 for_each_remote_ref(show_reference, NULL);
472                                 continue;
473                         }
474                         if (!strcmp(arg, "--show-prefix")) {
475                                 if (prefix)
476                                         puts(prefix);
477                                 continue;
478                         }
479                         if (!strcmp(arg, "--show-cdup")) {
480                                 const char *pfx = prefix;
481                                 if (!is_inside_work_tree()) {
482                                         const char *work_tree =
483                                                 get_git_work_tree();
484                                         if (work_tree)
485                                                 printf("%s\n", work_tree);
486                                         continue;
487                                 }
488                                 while (pfx) {
489                                         pfx = strchr(pfx, '/');
490                                         if (pfx) {
491                                                 pfx++;
492                                                 printf("../");
493                                         }
494                                 }
495                                 putchar('\n');
496                                 continue;
497                         }
498                         if (!strcmp(arg, "--git-dir")) {
499                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
500                                 static char cwd[PATH_MAX];
501                                 if (gitdir) {
502                                         puts(gitdir);
503                                         continue;
504                                 }
505                                 if (!prefix) {
506                                         puts(".git");
507                                         continue;
508                                 }
509                                 if (!getcwd(cwd, PATH_MAX))
510                                         die("unable to get current working directory");
511                                 printf("%s/.git\n", cwd);
512                                 continue;
513                         }
514                         if (!strcmp(arg, "--is-inside-git-dir")) {
515                                 printf("%s\n", is_inside_git_dir() ? "true"
516                                                 : "false");
517                                 continue;
518                         }
519                         if (!strcmp(arg, "--is-inside-work-tree")) {
520                                 printf("%s\n", is_inside_work_tree() ? "true"
521                                                 : "false");
522                                 continue;
523                         }
524                         if (!strcmp(arg, "--is-bare-repository")) {
525                                 printf("%s\n", is_bare_repository() ? "true"
526                                                 : "false");
527                                 continue;
528                         }
529                         if (!prefixcmp(arg, "--since=")) {
530                                 show_datestring("--max-age=", arg+8);
531                                 continue;
532                         }
533                         if (!prefixcmp(arg, "--after=")) {
534                                 show_datestring("--max-age=", arg+8);
535                                 continue;
536                         }
537                         if (!prefixcmp(arg, "--before=")) {
538                                 show_datestring("--min-age=", arg+9);
539                                 continue;
540                         }
541                         if (!prefixcmp(arg, "--until=")) {
542                                 show_datestring("--min-age=", arg+8);
543                                 continue;
544                         }
545                         if (show_flag(arg) && verify)
546                                 die("Needed a single revision");
547                         continue;
548                 }
549
550                 /* Not a flag argument */
551                 if (try_difference(arg))
552                         continue;
553                 if (!get_sha1(arg, sha1)) {
554                         show_rev(NORMAL, sha1, arg);
555                         continue;
556                 }
557                 if (*arg == '^' && !get_sha1(arg+1, sha1)) {
558                         show_rev(REVERSED, sha1, arg+1);
559                         continue;
560                 }
561                 as_is = 1;
562                 if (!show_file(arg))
563                         continue;
564                 if (verify)
565                         die("Needed a single revision");
566                 verify_filename(prefix, arg);
567         }
568         show_default();
569         if (verify && revs_count != 1)
570                 die("Needed a single revision");
571         return 0;
572 }