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
16static int filter = ~0;
17
18static const char *def = NULL;
19
20#define NORMAL 0
21#define REVERSED 1
22static int show_type = NORMAL;
23static int symbolic = 0;
24static int abbrev = 0;
25static int output_sq = 0;
26
27static 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 */
34static 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 */
77static 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 */
96static 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. */
114static 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
125static 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
140static int show_reference(const char *refname, const unsigned char *sha1)
141{
142 show_rev(NORMAL, sha1, refname);
143 return 0;
144}
145
146static 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
157static 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
167static 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
212int 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}