gitweb: configurable home link string
[alt-git.git] / builtin-diff.c
blob82afce782d88a1f773599332910982ef804aea12
1 /*
2 * Builtin "git diff"
4 * Copyright (c) 2006 Junio C Hamano
5 */
6 #include "cache.h"
7 #include "commit.h"
8 #include "blob.h"
9 #include "tag.h"
10 #include "diff.h"
11 #include "diffcore.h"
12 #include "revision.h"
13 #include "log-tree.h"
14 #include "builtin.h"
16 /* NEEDSWORK: struct object has place for name but we _do_
17 * know mode when we extracted the blob out of a tree, which
18 * we currently lose.
20 struct blobinfo {
21 unsigned char sha1[20];
22 const char *name;
25 static const char builtin_diff_usage[] =
26 "git-diff <options> <rev>{0,2} -- <path>*";
28 static int builtin_diff_files(struct rev_info *revs,
29 int argc, const char **argv)
31 int silent = 0;
32 while (1 < argc) {
33 const char *arg = argv[1];
34 if (!strcmp(arg, "--base"))
35 revs->max_count = 1;
36 else if (!strcmp(arg, "--ours"))
37 revs->max_count = 2;
38 else if (!strcmp(arg, "--theirs"))
39 revs->max_count = 3;
40 else if (!strcmp(arg, "-q"))
41 silent = 1;
42 else
43 usage(builtin_diff_usage);
44 argv++; argc--;
47 * Make sure there are NO revision (i.e. pending object) parameter,
48 * specified rev.max_count is reasonable (0 <= n <= 3), and
49 * there is no other revision filtering parameter.
51 if (revs->pending.nr ||
52 revs->min_age != -1 ||
53 revs->max_age != -1 ||
54 3 < revs->max_count)
55 usage(builtin_diff_usage);
56 if (revs->max_count < 0 &&
57 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
58 revs->combine_merges = revs->dense_combined_merges = 1;
59 return run_diff_files(revs, silent);
62 static void stuff_change(struct diff_options *opt,
63 unsigned old_mode, unsigned new_mode,
64 const unsigned char *old_sha1,
65 const unsigned char *new_sha1,
66 const char *old_name,
67 const char *new_name)
69 struct diff_filespec *one, *two;
71 if (memcmp(null_sha1, old_sha1, 20) &&
72 memcmp(null_sha1, new_sha1, 20) &&
73 !memcmp(old_sha1, new_sha1, 20))
74 return;
76 if (opt->reverse_diff) {
77 unsigned tmp;
78 const unsigned char *tmp_u;
79 const char *tmp_c;
80 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
81 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
82 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
84 one = alloc_filespec(old_name);
85 two = alloc_filespec(new_name);
86 fill_filespec(one, old_sha1, old_mode);
87 fill_filespec(two, new_sha1, new_mode);
89 /* NEEDSWORK: shouldn't this part of diffopt??? */
90 diff_queue(&diff_queued_diff, one, two);
93 static int builtin_diff_b_f(struct rev_info *revs,
94 int argc, const char **argv,
95 struct blobinfo *blob,
96 const char *path)
98 /* Blob vs file in the working tree*/
99 struct stat st;
101 if (argc > 1)
102 usage(builtin_diff_usage);
104 if (lstat(path, &st))
105 die("'%s': %s", path, strerror(errno));
106 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
107 die("'%s': not a regular file or symlink", path);
108 stuff_change(&revs->diffopt,
109 canon_mode(st.st_mode), canon_mode(st.st_mode),
110 blob[0].sha1, null_sha1,
111 path, path);
112 diffcore_std(&revs->diffopt);
113 diff_flush(&revs->diffopt);
114 return 0;
117 static int builtin_diff_blobs(struct rev_info *revs,
118 int argc, const char **argv,
119 struct blobinfo *blob)
121 unsigned mode = canon_mode(S_IFREG | 0644);
123 if (argc > 1)
124 usage(builtin_diff_usage);
126 stuff_change(&revs->diffopt,
127 mode, mode,
128 blob[0].sha1, blob[1].sha1,
129 blob[0].name, blob[1].name);
130 diffcore_std(&revs->diffopt);
131 diff_flush(&revs->diffopt);
132 return 0;
135 static int builtin_diff_index(struct rev_info *revs,
136 int argc, const char **argv)
138 int cached = 0;
139 while (1 < argc) {
140 const char *arg = argv[1];
141 if (!strcmp(arg, "--cached"))
142 cached = 1;
143 else
144 usage(builtin_diff_usage);
145 argv++; argc--;
148 * Make sure there is one revision (i.e. pending object),
149 * and there is no revision filtering parameters.
151 if (revs->pending.nr != 1 ||
152 revs->max_count != -1 || revs->min_age != -1 ||
153 revs->max_age != -1)
154 usage(builtin_diff_usage);
155 return run_diff_index(revs, cached);
158 static int builtin_diff_tree(struct rev_info *revs,
159 int argc, const char **argv,
160 struct object_array_entry *ent)
162 const unsigned char *(sha1[2]);
163 int swap = 0;
165 if (argc > 1)
166 usage(builtin_diff_usage);
168 /* We saw two trees, ent[0] and ent[1].
169 * if ent[1] is uninteresting, they are swapped
171 if (ent[1].item->flags & UNINTERESTING)
172 swap = 1;
173 sha1[swap] = ent[0].item->sha1;
174 sha1[1-swap] = ent[1].item->sha1;
175 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
176 log_tree_diff_flush(revs);
177 return 0;
180 static int builtin_diff_combined(struct rev_info *revs,
181 int argc, const char **argv,
182 struct object_array_entry *ent,
183 int ents)
185 const unsigned char (*parent)[20];
186 int i;
188 if (argc > 1)
189 usage(builtin_diff_usage);
191 if (!revs->dense_combined_merges && !revs->combine_merges)
192 revs->dense_combined_merges = revs->combine_merges = 1;
193 parent = xmalloc(ents * sizeof(*parent));
194 /* Again, the revs are all reverse */
195 for (i = 0; i < ents; i++)
196 memcpy(parent + i, ent[ents - 1 - i].item->sha1, 20);
197 diff_tree_combined(parent[0], parent + 1, ents - 1,
198 revs->dense_combined_merges, revs);
199 return 0;
202 void add_head(struct rev_info *revs)
204 unsigned char sha1[20];
205 struct object *obj;
206 if (get_sha1("HEAD", sha1))
207 return;
208 obj = parse_object(sha1);
209 if (!obj)
210 return;
211 add_pending_object(revs, obj, "HEAD");
214 int cmd_diff(int argc, const char **argv, const char *prefix)
216 int i;
217 struct rev_info rev;
218 struct object_array_entry ent[100];
219 int ents = 0, blobs = 0, paths = 0;
220 const char *path = NULL;
221 struct blobinfo blob[2];
224 * We could get N tree-ish in the rev.pending_objects list.
225 * Also there could be M blobs there, and P pathspecs.
227 * N=0, M=0:
228 * cache vs files (diff-files)
229 * N=0, M=2:
230 * compare two random blobs. P must be zero.
231 * N=0, M=1, P=1:
232 * compare a blob with a working tree file.
234 * N=1, M=0:
235 * tree vs cache (diff-index --cached)
237 * N=2, M=0:
238 * tree vs tree (diff-tree)
240 * Other cases are errors.
243 git_config(git_diff_ui_config);
244 init_revisions(&rev, prefix);
246 argc = setup_revisions(argc, argv, &rev, NULL);
247 if (!rev.diffopt.output_format) {
248 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
249 if (diff_setup_done(&rev.diffopt) < 0)
250 die("diff_setup_done failed");
253 /* Do we have --cached and not have a pending object, then
254 * default to HEAD by hand. Eek.
256 if (!rev.pending.nr) {
257 int i;
258 for (i = 1; i < argc; i++) {
259 const char *arg = argv[i];
260 if (!strcmp(arg, "--"))
261 break;
262 else if (!strcmp(arg, "--cached")) {
263 add_head(&rev);
264 break;
269 for (i = 0; i < rev.pending.nr; i++) {
270 struct object_array_entry *list = rev.pending.objects+i;
271 struct object *obj = list->item;
272 const char *name = list->name;
273 int flags = (obj->flags & UNINTERESTING);
274 if (!obj->parsed)
275 obj = parse_object(obj->sha1);
276 obj = deref_tag(obj, NULL, 0);
277 if (!obj)
278 die("invalid object '%s' given.", name);
279 if (obj->type == OBJ_COMMIT)
280 obj = &((struct commit *)obj)->tree->object;
281 if (obj->type == OBJ_TREE) {
282 if (ARRAY_SIZE(ent) <= ents)
283 die("more than %d trees given: '%s'",
284 (int) ARRAY_SIZE(ent), name);
285 obj->flags |= flags;
286 ent[ents].item = obj;
287 ent[ents].name = name;
288 ents++;
289 continue;
291 if (obj->type == OBJ_BLOB) {
292 if (2 <= blobs)
293 die("more than two blobs given: '%s'", name);
294 memcpy(blob[blobs].sha1, obj->sha1, 20);
295 blob[blobs].name = name;
296 blobs++;
297 continue;
300 die("unhandled object '%s' given.", name);
302 if (rev.prune_data) {
303 const char **pathspec = rev.prune_data;
304 while (*pathspec) {
305 if (!path)
306 path = *pathspec;
307 paths++;
308 pathspec++;
313 * Now, do the arguments look reasonable?
315 if (!ents) {
316 switch (blobs) {
317 case 0:
318 return builtin_diff_files(&rev, argc, argv);
319 break;
320 case 1:
321 if (paths != 1)
322 usage(builtin_diff_usage);
323 return builtin_diff_b_f(&rev, argc, argv, blob, path);
324 break;
325 case 2:
326 if (paths)
327 usage(builtin_diff_usage);
328 return builtin_diff_blobs(&rev, argc, argv, blob);
329 break;
330 default:
331 usage(builtin_diff_usage);
334 else if (blobs)
335 usage(builtin_diff_usage);
336 else if (ents == 1)
337 return builtin_diff_index(&rev, argc, argv);
338 else if (ents == 2)
339 return builtin_diff_tree(&rev, argc, argv, ent);
340 else if ((ents == 3) && (ent[0].item->flags & UNINTERESTING)) {
341 /* diff A...B where there is one sane merge base between
342 * A and B. We have ent[0] == merge-base, ent[1] == A,
343 * and ent[2] == B. Show diff between the base and B.
345 ent[1] = ent[2];
346 return builtin_diff_tree(&rev, argc, argv, ent);
348 else
349 return builtin_diff_combined(&rev, argc, argv,
350 ent, ents);
351 usage(builtin_diff_usage);