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[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
12 #define DO_REVS         1
13 #define DO_NOREV        2
14 #define DO_FLAGS        4
15 #define DO_NONFLAGS     8
16 static int filter = ~0;
17
18 static const char *def = NULL;
19
20 #define NORMAL 0
21 #define REVERSED 1
22 static int show_type = NORMAL;
23 static int symbolic = 0;
24 static int abbrev = 0;
25 static int output_sq = 0;
26
27 static int revs_count = 0;
28
29 /*
30  * Some arguments are relevant "revision" arguments,
31  * others are about output format or other details.
32  * This sorts it all out.
33  */
34 static int is_rev_argument(const char *arg)
35 {
36         static const char *rev_args[] = {
37                 "--all",
38                 "--bisect",
39                 "--dense",
40                 "--branches",
41                 "--header",
42                 "--max-age=",
43                 "--max-count=",
44                 "--min-age=",
45                 "--no-merges",
46                 "--objects",
47                 "--objects-edge",
48                 "--parents",
49                 "--pretty",
50                 "--remotes",
51                 "--sparse",
52                 "--tags",
53                 "--topo-order",
54                 "--date-order",
55                 "--unpacked",
56                 NULL
57         };
58         const char **p = rev_args;
59
60         /* accept -<digit>, like traditional "head" */
61         if ((*arg == '-') && isdigit(arg[1]))
62                 return 1;
63
64         for (;;) {
65                 const char *str = *p++;
66                 int len;
67                 if (!str)
68                         return 0;
69                 len = strlen(str);
70                 if (!strcmp(arg, str) ||
71                     (str[len-1] == '=' && !strncmp(arg, str, len)))
72                         return 1;
73         }
74 }
75
76 /* Output argument as a string, either SQ or normal */
77 static void show(const char *arg)
78 {
79         if (output_sq) {
80                 int sq = '\'', ch;
81
82                 putchar(sq);
83                 while ((ch = *arg++)) {
84                         if (ch == sq)
85                                 fputs("'\\'", stdout);
86                         putchar(ch);
87                 }
88                 putchar(sq);
89                 putchar(' ');
90         }
91         else
92                 puts(arg);
93 }
94
95 /* Output a revision, only if filter allows it */
96 static void show_rev(int type, const unsigned char *sha1, const char *name)
97 {
98         if (!(filter & DO_REVS))
99                 return;
100         def = NULL;
101         revs_count++;
102
103         if (type != show_type)
104                 putchar('^');
105         if (symbolic && name)
106                 show(name);
107         else if (abbrev)
108                 show(find_unique_abbrev(sha1, abbrev));
109         else
110                 show(sha1_to_hex(sha1));
111 }
112
113 /* Output a flag, only if filter allows it. */
114 static int show_flag(const char *arg)
115 {
116         if (!(filter & DO_FLAGS))
117                 return 0;
118         if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
119                 show(arg);
120                 return 1;
121         }
122         return 0;
123 }
124
125 static void show_default(void)
126 {
127         const char *s = def;
128
129         if (s) {
130                 unsigned char sha1[20];
131
132                 def = NULL;
133                 if (!get_sha1(s, sha1)) {
134                         show_rev(NORMAL, sha1, s);
135                         return;
136                 }
137         }
138 }
139
140 static int show_reference(const char *refname, const unsigned char *sha1)
141 {
142         show_rev(NORMAL, sha1, refname);
143         return 0;
144 }
145
146 static void show_datestring(const char *flag, const char *datestr)
147 {
148         static char buffer[100];
149
150         /* date handling requires both flags and revs */
151         if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
152                 return;
153         snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
154         show(buffer);
155 }
156
157 static int show_file(const char *arg)
158 {
159         show_default();
160         if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
161                 show(arg);
162                 return 1;
163         }
164         return 0;
165 }
166
167 static int try_difference(const char *arg)
168 {
169         char *dotdot;
170         unsigned char sha1[20];
171         unsigned char end[20];
172         const char *next;
173         const char *this;
174         int symmetric;
175
176         if (!(dotdot = strstr(arg, "..")))
177                 return 0;
178         next = dotdot + 2;
179         this = arg;
180         symmetric = (*next == '.');
181
182         *dotdot = 0;
183         next += symmetric;
184
185         if (!*next)
186                 next = "HEAD";
187         if (dotdot == arg)
188                 this = "HEAD";
189         if (!get_sha1(this, sha1) && !get_sha1(next, end)) {
190                 show_rev(NORMAL, end, next);
191                 show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
192                 if (symmetric) {
193                         struct commit_list *exclude;
194                         struct commit *a, *b;
195                         a = lookup_commit_reference(sha1);
196                         b = lookup_commit_reference(end);
197                         exclude = get_merge_bases(a, b, 1);
198                         while (exclude) {
199                                 struct commit_list *n = exclude->next;
200                                 show_rev(REVERSED,
201                                          exclude->item->object.sha1,NULL);
202                                 free(exclude);
203                                 exclude = n;
204                         }
205                 }
206                 return 1;
207         }
208         *dotdot = '.';
209         return 0;
210 }
211
212 int cmd_rev_parse(int argc, const char **argv, char **envp)
213 {
214         int i, as_is = 0, verify = 0;
215         unsigned char sha1[20];
216         const char *prefix = setup_git_directory();
217
218         git_config(git_default_config);
219
220         for (i = 1; i < argc; i++) {
221                 const char *arg = argv[i];
222
223                 if (as_is) {
224                         if (show_file(arg) && as_is < 2)
225                                 verify_filename(prefix, arg);
226                         continue;
227                 }
228                 if (!strcmp(arg,"-n")) {
229                         if (++i >= argc)
230                                 die("-n requires an argument");
231                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
232                                 show(arg);
233                                 show(argv[i]);
234                         }
235                         continue;
236                 }
237                 if (!strncmp(arg,"-n",2)) {
238                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
239                                 show(arg);
240                         continue;
241                 }
242
243                 if (*arg == '-') {
244                         if (!strcmp(arg, "--")) {
245                                 as_is = 2;
246                                 /* Pass on the "--" if we show anything but files.. */
247                                 if (filter & (DO_FLAGS | DO_REVS))
248                                         show_file(arg);
249                                 continue;
250                         }
251                         if (!strcmp(arg, "--default")) {
252                                 def = argv[i+1];
253                                 i++;
254                                 continue;
255                         }
256                         if (!strcmp(arg, "--revs-only")) {
257                                 filter &= ~DO_NOREV;
258                                 continue;
259                         }
260                         if (!strcmp(arg, "--no-revs")) {
261                                 filter &= ~DO_REVS;
262                                 continue;
263                         }
264                         if (!strcmp(arg, "--flags")) {
265                                 filter &= ~DO_NONFLAGS;
266                                 continue;
267                         }
268                         if (!strcmp(arg, "--no-flags")) {
269                                 filter &= ~DO_FLAGS;
270                                 continue;
271                         }
272                         if (!strcmp(arg, "--verify")) {
273                                 filter &= ~(DO_FLAGS|DO_NOREV);
274                                 verify = 1;
275                                 continue;
276                         }
277                         if (!strcmp(arg, "--short") ||
278                             !strncmp(arg, "--short=", 8)) {
279                                 filter &= ~(DO_FLAGS|DO_NOREV);
280                                 verify = 1;
281                                 abbrev = DEFAULT_ABBREV;
282                                 if (arg[7] == '=')
283                                         abbrev = strtoul(arg + 8, NULL, 10);
284                                 if (abbrev < MINIMUM_ABBREV)
285                                         abbrev = MINIMUM_ABBREV;
286                                 else if (40 <= abbrev)
287                                         abbrev = 40;
288                                 continue;
289                         }
290                         if (!strcmp(arg, "--sq")) {
291                                 output_sq = 1;
292                                 continue;
293                         }
294                         if (!strcmp(arg, "--not")) {
295                                 show_type ^= REVERSED;
296                                 continue;
297                         }
298                         if (!strcmp(arg, "--symbolic")) {
299                                 symbolic = 1;
300                                 continue;
301                         }
302                         if (!strcmp(arg, "--all")) {
303                                 for_each_ref(show_reference);
304                                 continue;
305                         }
306                         if (!strcmp(arg, "--branches")) {
307                                 for_each_branch_ref(show_reference);
308                                 continue;
309                         }
310                         if (!strcmp(arg, "--tags")) {
311                                 for_each_tag_ref(show_reference);
312                                 continue;
313                         }
314                         if (!strcmp(arg, "--remotes")) {
315                                 for_each_remote_ref(show_reference);
316                                 continue;
317                         }
318                         if (!strcmp(arg, "--show-prefix")) {
319                                 if (prefix)
320                                         puts(prefix);
321                                 continue;
322                         }
323                         if (!strcmp(arg, "--show-cdup")) {
324                                 const char *pfx = prefix;
325                                 while (pfx) {
326                                         pfx = strchr(pfx, '/');
327                                         if (pfx) {
328                                                 pfx++;
329                                                 printf("../");
330                                         }
331                                 }
332                                 putchar('\n');
333                                 continue;
334                         }
335                         if (!strcmp(arg, "--git-dir")) {
336                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
337                                 static char cwd[PATH_MAX];
338                                 if (gitdir) {
339                                         puts(gitdir);
340                                         continue;
341                                 }
342                                 if (!prefix) {
343                                         puts(".git");
344                                         continue;
345                                 }
346                                 if (!getcwd(cwd, PATH_MAX))
347                                         die("unable to get current working directory");
348                                 printf("%s/.git\n", cwd);
349                                 continue;
350                         }
351                         if (!strncmp(arg, "--since=", 8)) {
352                                 show_datestring("--max-age=", arg+8);
353                                 continue;
354                         }
355                         if (!strncmp(arg, "--after=", 8)) {
356                                 show_datestring("--max-age=", arg+8);
357                                 continue;
358                         }
359                         if (!strncmp(arg, "--before=", 9)) {
360                                 show_datestring("--min-age=", arg+9);
361                                 continue;
362                         }
363                         if (!strncmp(arg, "--until=", 8)) {
364                                 show_datestring("--min-age=", arg+8);
365                                 continue;
366                         }
367                         if (show_flag(arg) && verify)
368                                 die("Needed a single revision");
369                         continue;
370                 }
371
372                 /* Not a flag argument */
373                 if (try_difference(arg))
374                         continue;
375                 if (!get_sha1(arg, sha1)) {
376                         show_rev(NORMAL, sha1, arg);
377                         continue;
378                 }
379                 if (*arg == '^' && !get_sha1(arg+1, sha1)) {
380                         show_rev(REVERSED, sha1, arg+1);
381                         continue;
382                 }
383                 as_is = 1;
384                 if (!show_file(arg))
385                         continue;
386                 if (verify)
387                         die("Needed a single revision");
388                 verify_filename(prefix, arg);
389         }
390         show_default();
391         if (verify && revs_count != 1)
392                 die("Needed a single revision");
393         return 0;
394 }