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