Really honour NO_PYTHON
[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                 "--merge-order",
43                 "--min-age=",
44                 "--no-merges",
45                 "--objects",
46                 "--parents",
47                 "--pretty",
48                 "--show-breaks",
49                 "--sparse",
50                 "--topo-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         for (i = 1; i < argc; i++) {
170                 struct stat st;
171                 char *arg = argv[i];
172                 char *dotdot;
173         
174                 if (as_is) {
175                         show_file(arg);
176                         continue;
177                 }
178                 if (!strcmp(arg,"-n")) {
179                         if (++i >= argc)
180                                 die("-n requires an argument");
181                         if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
182                                 show(arg);
183                                 show(argv[i]);
184                         }
185                         continue;
186                 }
187                 if (!strncmp(arg,"-n",2)) {
188                         if ((filter & DO_FLAGS) && (filter & DO_REVS))
189                                 show(arg);
190                         continue;
191                 }
192
193                 if (*arg == '-') {
194                         if (!strcmp(arg, "--")) {
195                                 as_is = 1;
196                                 /* Pass on the "--" if we show anything but files.. */
197                                 if (filter & (DO_FLAGS | DO_REVS))
198                                         show_file(arg);
199                                 continue;
200                         }
201                         if (!strcmp(arg, "--default")) {
202                                 def = argv[i+1];
203                                 i++;
204                                 continue;
205                         }
206                         if (!strcmp(arg, "--revs-only")) {
207                                 filter &= ~DO_NOREV;
208                                 continue;
209                         }
210                         if (!strcmp(arg, "--no-revs")) {
211                                 filter &= ~DO_REVS;
212                                 continue;
213                         }
214                         if (!strcmp(arg, "--flags")) {
215                                 filter &= ~DO_NONFLAGS;
216                                 continue;
217                         }
218                         if (!strcmp(arg, "--no-flags")) {
219                                 filter &= ~DO_FLAGS;
220                                 continue;
221                         }
222                         if (!strcmp(arg, "--verify")) {
223                                 filter &= ~(DO_FLAGS|DO_NOREV);
224                                 verify = 1;
225                                 continue;
226                         }
227                         if (!strcmp(arg, "--short") ||
228                             !strncmp(arg, "--short=", 9)) {
229                                 filter &= ~(DO_FLAGS|DO_NOREV);
230                                 verify = 1;
231                                 abbrev = DEFAULT_ABBREV;
232                                 if (arg[8] == '=')
233                                         abbrev = strtoul(arg + 9, NULL, 10);
234                                 if (abbrev < MINIMUM_ABBREV)
235                                         abbrev = MINIMUM_ABBREV;
236                                 else if (40 <= abbrev)
237                                         abbrev = 40;
238                                 continue;
239                         }
240                         if (!strcmp(arg, "--sq")) {
241                                 output_sq = 1;
242                                 continue;
243                         }
244                         if (!strcmp(arg, "--not")) {
245                                 show_type ^= REVERSED;
246                                 continue;
247                         }
248                         if (!strcmp(arg, "--symbolic")) {
249                                 symbolic = 1;
250                                 continue;
251                         }
252                         if (!strcmp(arg, "--all")) {
253                                 for_each_ref(show_reference);
254                                 continue;
255                         }
256                         if (!strcmp(arg, "--show-prefix")) {
257                                 if (prefix)
258                                         puts(prefix);
259                                 continue;
260                         }
261                         if (!strcmp(arg, "--show-cdup")) {
262                                 const char *pfx = prefix;
263                                 while (pfx) {
264                                         pfx = strchr(pfx, '/');
265                                         if (pfx) {
266                                                 pfx++;
267                                                 printf("../");
268                                         }
269                                 }
270                                 putchar('\n');
271                                 continue;
272                         }
273                         if (!strcmp(arg, "--git-dir")) {
274                                 const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
275                                 static char cwd[PATH_MAX];
276                                 if (gitdir) {
277                                         puts(gitdir);
278                                         continue;
279                                 }
280                                 if (!prefix) {
281                                         puts(".git");
282                                         continue;
283                                 }
284                                 if (!getcwd(cwd, PATH_MAX))
285                                         die("unable to get current working directory");
286                                 printf("%s/.git\n", cwd);
287                                 continue;
288                         }
289                         if (!strncmp(arg, "--since=", 8)) {
290                                 show_datestring("--max-age=", arg+8);
291                                 continue;
292                         }
293                         if (!strncmp(arg, "--after=", 8)) {
294                                 show_datestring("--max-age=", arg+8);
295                                 continue;
296                         }
297                         if (!strncmp(arg, "--before=", 9)) {
298                                 show_datestring("--min-age=", arg+9);
299                                 continue;
300                         }
301                         if (!strncmp(arg, "--until=", 8)) {
302                                 show_datestring("--min-age=", arg+8);
303                                 continue;
304                         }
305                         if (show_flag(arg) && verify)
306                                 die("Needed a single revision");
307                         continue;
308                 }
309
310                 /* Not a flag argument */
311                 dotdot = strstr(arg, "..");
312                 if (dotdot) {
313                         unsigned char end[20];
314                         char *n = dotdot+2;
315                         *dotdot = 0;
316                         if (!get_sha1(arg, sha1)) {
317                                 if (!*n)
318                                         n = "HEAD";
319                                 if (!get_sha1(n, end)) {
320                                         show_rev(NORMAL, end, n);
321                                         show_rev(REVERSED, sha1, arg);
322                                         continue;
323                                 }
324                         }
325                         *dotdot = '.';
326                 }
327                 if (!get_sha1(arg, sha1)) {
328                         show_rev(NORMAL, sha1, arg);
329                         continue;
330                 }
331                 if (*arg == '^' && !get_sha1(arg+1, sha1)) {
332                         show_rev(REVERSED, sha1, arg+1);
333                         continue;
334                 }
335                 as_is = 1;
336                 if (!show_file(arg))
337                         continue;
338                 if (verify)
339                         die("Needed a single revision");
340                 if (lstat(arg, &st) < 0)
341                         die("'%s': %s", arg, strerror(errno));
342         }
343         show_default();
344         if (verify && revs_count != 1)
345                 die("Needed a single revision");
346         return 0;
347 }