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
88 const unsigned char *tmp_u;
89 const char *tmp_c;
90 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
91 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
92 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
93 }
94 one = alloc_filespec(old_name);
95 two = alloc_filespec(new_name);
96 fill_filespec(one, old_sha1, old_mode);
97 fill_filespec(two, new_sha1, new_mode);
98 /* NEEDSWORK: shouldn't this part of diffopt??? */
100 diff_queue(&diff_queued_diff, one, two);
101}
102static int builtin_diff_b_f(struct rev_info *revs,
104 int argc, const char **argv,
105 struct blobinfo *blob,
106 const char *path)
107{
108 /* Blob vs file in the working tree*/
109 struct stat st;
110 while (1 < argc) {
112 const char *arg = argv[1];
113 if (!strcmp(arg, "--raw"))
114 revs->diffopt.output_format = DIFF_FORMAT_RAW;
115 else
116 usage(builtin_diff_usage);
117 argv++; argc--;
118 }
119 if (lstat(path, &st))
120 die("'%s': %s", path, strerror(errno));
121 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
122 die("'%s': not a regular file or symlink", path);
123 stuff_change(&revs->diffopt,
124 canon_mode(st.st_mode), canon_mode(st.st_mode),
125 blob[0].sha1, null_sha1,
126 blob[0].name, path);
127 diffcore_std(&revs->diffopt);
128 diff_flush(&revs->diffopt);
129 return 0;
130}
131static int builtin_diff_blobs(struct rev_info *revs,
133 int argc, const char **argv,
134 struct blobinfo *blob)
135{
136 /* Blobs */
137 unsigned mode = canon_mode(S_IFREG | 0644);
138 while (1 < argc) {
140 const char *arg = argv[1];
141 if (!strcmp(arg, "--raw"))
142 revs->diffopt.output_format = DIFF_FORMAT_RAW;
143 else
144 usage(builtin_diff_usage);
145 argv++; argc--;
146 }
147 stuff_change(&revs->diffopt,
148 mode, mode,
149 blob[0].sha1, blob[1].sha1,
150 blob[1].name, blob[1].name);
151 diffcore_std(&revs->diffopt);
152 diff_flush(&revs->diffopt);
153 return 0;
154}
155static int builtin_diff_index(struct rev_info *revs,
157 int argc, const char **argv)
158{
159 int cached = 0;
160 while (1 < argc) {
161 const char *arg = argv[1];
162 if (!strcmp(arg, "--cached"))
163 cached = 1;
164 else if (!strcmp(arg, "--raw"))
165 revs->diffopt.output_format = DIFF_FORMAT_RAW;
166 else
167 usage(builtin_diff_usage);
168 argv++; argc--;
169 }
170 /*
171 * Make sure there is one revision (i.e. pending object),
172 * and there is no revision filtering parameters.
173 */
174 if (!revs->pending_objects || revs->pending_objects->next ||
175 revs->max_count != -1 || revs->min_age != -1 ||
176 revs->max_age != -1)
177 usage(builtin_diff_usage);
178 return run_diff_index(revs, cached);
179}
180static int builtin_diff_tree(struct rev_info *revs,
182 int argc, const char **argv,
183 struct object_list *ent)
184{
185 const unsigned char *(sha1[2]);
186 int swap = 1;
187 while (1 < argc) {
188 const char *arg = argv[1];
189 if (!strcmp(arg, "--raw"))
190 revs->diffopt.output_format = DIFF_FORMAT_RAW;
191 else
192 usage(builtin_diff_usage);
193 argv++; argc--;
194 }
195 /* We saw two trees, ent[0] and ent[1].
197 * unless ent[0] is unintesting, they are swapped
198 */
199 if (ent[0].item->flags & UNINTERESTING)
200 swap = 0;
201 sha1[swap] = ent[0].item->sha1;
202 sha1[1-swap] = ent[1].item->sha1;
203 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
204 log_tree_diff_flush(revs);
205 return 0;
206}
207static int builtin_diff_combined(struct rev_info *revs,
209 int argc, const char **argv,
210 struct object_list *ent,
211 int ents)
212{
213 const unsigned char (*parent)[20];
214 int i;
215 while (1 < argc) {
217 const char *arg = argv[1];
218 if (!strcmp(arg, "--raw"))
219 revs->diffopt.output_format = DIFF_FORMAT_RAW;
220 else
221 usage(builtin_diff_usage);
222 argv++; argc--;
223 }
224 if (!revs->dense_combined_merges && !revs->combine_merges)
225 revs->dense_combined_merges = revs->combine_merges = 1;
226 parent = xmalloc(ents * sizeof(*parent));
227 /* Again, the revs are all reverse */
228 for (i = 0; i < ents; i++)
229 memcpy(parent + i, ent[ents - 1 - i].item->sha1, 20);
230 diff_tree_combined(parent[0], parent + 1, ents - 1,
231 revs->dense_combined_merges, revs);
232 return 0;
233}
234static void add_head(struct rev_info *revs)
236{
237 unsigned char sha1[20];
238 struct object *obj;
239 if (get_sha1("HEAD", sha1))
240 return;
241 obj = parse_object(sha1);
242 if (!obj)
243 return;
244 add_object(obj, &revs->pending_objects, NULL, "HEAD");
245}
246int cmd_diff(int argc, const char **argv, char **envp)
248{
249 struct rev_info rev;
250 struct object_list *list, ent[100];
251 int ents = 0, blobs = 0, paths = 0;
252 const char *path = NULL;
253 struct blobinfo blob[2];
254 /*
256 * We could get N tree-ish in the rev.pending_objects list.
257 * Also there could be M blobs there, and P pathspecs.
258 *
259 * N=0, M=0:
260 * cache vs files (diff-files)
261 * N=0, M=2:
262 * compare two random blobs. P must be zero.
263 * N=0, M=1, P=1:
264 * compare a blob with a working tree file.
265 *
266 * N=1, M=0:
267 * tree vs cache (diff-index --cached)
268 *
269 * N=2, M=0:
270 * tree vs tree (diff-tree)
271 *
272 * Other cases are errors.
273 */
274
275 git_config(git_diff_config);
276 init_revisions(&rev);
277 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
278 argc = setup_revisions(argc, argv, &rev, NULL);
280 /* Do we have --cached and not have a pending object, then
281 * default to HEAD by hand. Eek.
282 */
283 if (!rev.pending_objects) {
284 int i;
285 for (i = 1; i < argc; i++) {
286 const char *arg = argv[i];
287 if (!strcmp(arg, "--"))
288 break;
289 else if (!strcmp(arg, "--cached")) {
290 add_head(&rev);
291 break;
292 }
293 }
294 }
295 for (list = rev.pending_objects; list; list = list->next) {
297 struct object *obj = list->item;
298 const char *name = list->name;
299 int flags = (obj->flags & UNINTERESTING);
300 if (!obj->parsed)
301 obj = parse_object(obj->sha1);
302 obj = deref_tag(obj, NULL, 0);
303 if (!obj)
304 die("invalid object '%s' given.", name);
305 if (!strcmp(obj->type, commit_type))
306 obj = &((struct commit *)obj)->tree->object;
307 if (!strcmp(obj->type, tree_type)) {
308 if (ARRAY_SIZE(ent) <= ents)
309 die("more than %d trees given: '%s'",
310 (int) ARRAY_SIZE(ent), name);
311 obj->flags |= flags;
312 ent[ents].item = obj;
313 ent[ents].name = name;
314 ents++;
315 continue;
316 }
317 if (!strcmp(obj->type, blob_type)) {
318 if (2 <= blobs)
319 die("more than two blobs given: '%s'", name);
320 memcpy(blob[blobs].sha1, obj->sha1, 20);
321 blob[blobs].name = name;
322 blobs++;
323 continue;
324
325 }
326 die("unhandled object '%s' given.", name);
327 }
328 if (rev.prune_data) {
329 const char **pathspec = rev.prune_data;
330 while (*pathspec) {
331 if (!path)
332 path = *pathspec;
333 paths++;
334 pathspec++;
335 }
336 }
337 /*
339 * Now, do the arguments look reasonable?
340 */
341 if (!ents) {
342 switch (blobs) {
343 case 0:
344 return builtin_diff_files(&rev, argc, argv);
345 break;
346 case 1:
347 if (paths != 1)
348 usage(builtin_diff_usage);
349 return builtin_diff_b_f(&rev, argc, argv, blob, path);
350 break;
351 case 2:
352 if (paths)
353 usage(builtin_diff_usage);
354 return builtin_diff_blobs(&rev, argc, argv, blob);
355 break;
356 default:
357 usage(builtin_diff_usage);
358 }
359 }
360 else if (blobs)
361 usage(builtin_diff_usage);
362 else if (ents == 1)
363 return builtin_diff_index(&rev, argc, argv);
364 else if (ents == 2)
365 return builtin_diff_tree(&rev, argc, argv, ent);
366 else
367 return builtin_diff_combined(&rev, argc, argv, ent, ents);
368 usage(builtin_diff_usage);
369}