1/*
2 * Builtin "git diff"
3 *
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"
15/* 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.
19 */
20struct blobinfo {
21 unsigned char sha1[20];
22 const char *name;
23};
24static const char builtin_diff_usage[] =
26"diff <options> <rev>{0,2} -- <path>*";
27static int builtin_diff_files(struct rev_info *revs,
29 int argc, const char **argv)
30{
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 if (!strcmp(arg, "--raw"))
43 revs->diffopt.output_format = DIFF_FORMAT_RAW;
44 else
45 usage(builtin_diff_usage);
46 argv++; argc--;
47 }
48 /*
49 * Make sure there are NO revision (i.e. pending object) parameter,
50 * specified rev.max_count is reasonable (0 <= n <= 3), and
51 * there is no other revision filtering parameter.
52 */
53 if (revs->pending_objects ||
54 revs->min_age != -1 ||
55 revs->max_age != -1 ||
56 3 < revs->max_count)
57 usage(builtin_diff_usage);
58 if (revs->max_count < 0 &&
59 (revs->diffopt.output_format == DIFF_FORMAT_PATCH))
60 revs->combine_merges = revs->dense_combined_merges = 1;
61 /*
62 * Backward compatibility wart - "diff-files -s" used to
63 * defeat the common diff option "-s" which asked for
64 * DIFF_FORMAT_NO_OUTPUT.
65 */
66 if (revs->diffopt.output_format == DIFF_FORMAT_NO_OUTPUT)
67 revs->diffopt.output_format = DIFF_FORMAT_RAW;
68 return run_diff_files(revs, silent);
69}
70static void stuff_change(struct diff_options *opt,
72 unsigned old_mode, unsigned new_mode,
73 const unsigned char *old_sha1,
74 const unsigned char *new_sha1,
75 const char *old_name,
76 const char *new_name)
77{
78 struct diff_filespec *one, *two;
79 if (memcmp(null_sha1, old_sha1, 20) &&
81 memcmp(null_sha1, new_sha1, 20) &&
82 !memcmp(old_sha1, new_sha1, 20))
83 return;
84 if (opt->reverse_diff) {
86 unsigned tmp;
87 const unsigned char *tmp_u;
88 const char *tmp_c;
89 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
90 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
91 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
92 }
93 one = alloc_filespec(old_name);
94 two = alloc_filespec(new_name);
95 fill_filespec(one, old_sha1, old_mode);
96 fill_filespec(two, new_sha1, new_mode);
97 /* NEEDSWORK: shouldn't this part of diffopt??? */
99 diff_queue(&diff_queued_diff, one, two);
100}
101static int builtin_diff_b_f(struct rev_info *revs,
103 int argc, const char **argv,
104 struct blobinfo *blob,
105 const char *path)
106{
107 /* Blob vs file in the working tree*/
108 struct stat st;
109 while (1 < argc) {
111 const char *arg = argv[1];
112 if (!strcmp(arg, "--raw"))
113 revs->diffopt.output_format = DIFF_FORMAT_RAW;
114 else
115 usage(builtin_diff_usage);
116 argv++; argc--;
117 }
118 if (lstat(path, &st))
119 die("'%s': %s", path, strerror(errno));
120 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
121 die("'%s': not a regular file or symlink", path);
122 stuff_change(&revs->diffopt,
123 canon_mode(st.st_mode), canon_mode(st.st_mode),
124 blob[0].sha1, null_sha1,
125 path, path);
126 diffcore_std(&revs->diffopt);
127 diff_flush(&revs->diffopt);
128 return 0;
129}
130static int builtin_diff_blobs(struct rev_info *revs,
132 int argc, const char **argv,
133 struct blobinfo *blob)
134{
135 /* Blobs: the arguments are reversed when setup_revisions()
136 * picked them up.
137 */
138 unsigned mode = canon_mode(S_IFREG | 0644);
139 while (1 < argc) {
141 const char *arg = argv[1];
142 if (!strcmp(arg, "--raw"))
143 revs->diffopt.output_format = DIFF_FORMAT_RAW;
144 else
145 usage(builtin_diff_usage);
146 argv++; argc--;
147 }
148 stuff_change(&revs->diffopt,
149 mode, mode,
150 blob[1].sha1, blob[0].sha1,
151 blob[0].name, blob[0].name);
152 diffcore_std(&revs->diffopt);
153 diff_flush(&revs->diffopt);
154 return 0;
155}
156static int builtin_diff_index(struct rev_info *revs,
158 int argc, const char **argv)
159{
160 int cached = 0;
161 while (1 < argc) {
162 const char *arg = argv[1];
163 if (!strcmp(arg, "--cached"))
164 cached = 1;
165 else if (!strcmp(arg, "--raw"))
166 revs->diffopt.output_format = DIFF_FORMAT_RAW;
167 else
168 usage(builtin_diff_usage);
169 argv++; argc--;
170 }
171 /*
172 * Make sure there is one revision (i.e. pending object),
173 * and there is no revision filtering parameters.
174 */
175 if (!revs->pending_objects || revs->pending_objects->next ||
176 revs->max_count != -1 || revs->min_age != -1 ||
177 revs->max_age != -1)
178 usage(builtin_diff_usage);
179 return run_diff_index(revs, cached);
180}
181static int builtin_diff_tree(struct rev_info *revs,
183 int argc, const char **argv,
184 struct object_list *ent)
185{
186 const unsigned char *(sha1[2]);
187 int swap = 1;
188 while (1 < argc) {
189 const char *arg = argv[1];
190 if (!strcmp(arg, "--raw"))
191 revs->diffopt.output_format = DIFF_FORMAT_RAW;
192 else
193 usage(builtin_diff_usage);
194 argv++; argc--;
195 }
196 /* We saw two trees, ent[0] and ent[1].
198 * unless ent[0] is unintesting, they are swapped
199 */
200 if (ent[0].item->flags & UNINTERESTING)
201 swap = 0;
202 sha1[swap] = ent[0].item->sha1;
203 sha1[1-swap] = ent[1].item->sha1;
204 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
205 log_tree_diff_flush(revs);
206 return 0;
207}
208static int builtin_diff_combined(struct rev_info *revs,
210 int argc, const char **argv,
211 struct object_list *ent,
212 int ents)
213{
214 const unsigned char (*parent)[20];
215 int i;
216 while (1 < argc) {
218 const char *arg = argv[1];
219 if (!strcmp(arg, "--raw"))
220 revs->diffopt.output_format = DIFF_FORMAT_RAW;
221 else
222 usage(builtin_diff_usage);
223 argv++; argc--;
224 }
225 if (!revs->dense_combined_merges && !revs->combine_merges)
226 revs->dense_combined_merges = revs->combine_merges = 1;
227 parent = xmalloc(ents * sizeof(*parent));
228 /* Again, the revs are all reverse */
229 for (i = 0; i < ents; i++)
230 memcpy(parent + i, ent[ents - 1 - i].item->sha1, 20);
231 diff_tree_combined(parent[0], parent + 1, ents - 1,
232 revs->dense_combined_merges, revs);
233 return 0;
234}
235static void add_head(struct rev_info *revs)
237{
238 unsigned char sha1[20];
239 struct object *obj;
240 if (get_sha1("HEAD", sha1))
241 return;
242 obj = parse_object(sha1);
243 if (!obj)
244 return;
245 add_object(obj, &revs->pending_objects, NULL, "HEAD");
246}
247int cmd_diff(int argc, const char **argv, char **envp)
249{
250 struct rev_info rev;
251 struct object_list *list, ent[100];
252 int ents = 0, blobs = 0, paths = 0;
253 const char *path = NULL;
254 struct blobinfo blob[2];
255 /*
257 * We could get N tree-ish in the rev.pending_objects list.
258 * Also there could be M blobs there, and P pathspecs.
259 *
260 * N=0, M=0:
261 * cache vs files (diff-files)
262 * N=0, M=2:
263 * compare two random blobs. P must be zero.
264 * N=0, M=1, P=1:
265 * compare a blob with a working tree file.
266 *
267 * N=1, M=0:
268 * tree vs cache (diff-index --cached)
269 *
270 * N=2, M=0:
271 * tree vs tree (diff-tree)
272 *
273 * Other cases are errors.
274 */
275 git_config(git_diff_config);
277 init_revisions(&rev);
278 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
279 argc = setup_revisions(argc, argv, &rev, NULL);
281 /* Do we have --cached and not have a pending object, then
282 * default to HEAD by hand. Eek.
283 */
284 if (!rev.pending_objects) {
285 int i;
286 for (i = 1; i < argc; i++) {
287 const char *arg = argv[i];
288 if (!strcmp(arg, "--"))
289 break;
290 else if (!strcmp(arg, "--cached")) {
291 add_head(&rev);
292 break;
293 }
294 }
295 }
296 for (list = rev.pending_objects; list; list = list->next) {
298 struct object *obj = list->item;
299 const char *name = list->name;
300 int flags = (obj->flags & UNINTERESTING);
301 if (!obj->parsed)
302 obj = parse_object(obj->sha1);
303 obj = deref_tag(obj, NULL, 0);
304 if (!obj)
305 die("invalid object '%s' given.", name);
306 if (!strcmp(obj->type, commit_type))
307 obj = &((struct commit *)obj)->tree->object;
308 if (!strcmp(obj->type, tree_type)) {
309 if (ARRAY_SIZE(ent) <= ents)
310 die("more than %d trees given: '%s'",
311 (int) ARRAY_SIZE(ent), name);
312 obj->flags |= flags;
313 ent[ents].item = obj;
314 ent[ents].name = name;
315 ents++;
316 continue;
317 }
318 if (!strcmp(obj->type, blob_type)) {
319 if (2 <= blobs)
320 die("more than two blobs given: '%s'", name);
321 memcpy(blob[blobs].sha1, obj->sha1, 20);
322 blob[blobs].name = name;
323 blobs++;
324 continue;
325 }
327 die("unhandled object '%s' given.", name);
328 }
329 if (rev.prune_data) {
330 const char **pathspec = rev.prune_data;
331 while (*pathspec) {
332 if (!path)
333 path = *pathspec;
334 paths++;
335 pathspec++;
336 }
337 }
338 /*
340 * Now, do the arguments look reasonable?
341 */
342 if (!ents) {
343 switch (blobs) {
344 case 0:
345 return builtin_diff_files(&rev, argc, argv);
346 break;
347 case 1:
348 if (paths != 1)
349 usage(builtin_diff_usage);
350 return builtin_diff_b_f(&rev, argc, argv, blob, path);
351 break;
352 case 2:
353 if (paths)
354 usage(builtin_diff_usage);
355 return builtin_diff_blobs(&rev, argc, argv, blob);
356 break;
357 default:
358 usage(builtin_diff_usage);
359 }
360 }
361 else if (blobs)
362 usage(builtin_diff_usage);
363 else if (ents == 1)
364 return builtin_diff_index(&rev, argc, argv);
365 else if (ents == 2)
366 return builtin_diff_tree(&rev, argc, argv, ent);
367 else
368 return builtin_diff_combined(&rev, argc, argv, ent, ents);
369 usage(builtin_diff_usage);
370}