built-in diff.
[git/git.git] / builtin-diff.c
CommitLineData
65056021
JH
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
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.
19 */
20struct blobinfo {
21 unsigned char sha1[20];
22 const char *name;
23};
24
25static const char builtin_diff_usage[] =
26"diff <options> <rev>{0,2} -- <path>*";
27
28static 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 * rev.max_count is reasonable (0 <= n <= 3),
51 * there is no other revision filtering parameters.
52 */
53 if (revs->pending_objects ||
54 revs->min_age != -1 ||
55 revs->max_age != -1)
56 usage(builtin_diff_usage);
57 /*
58 * Backward compatibility wart - "diff-files -s" used to
59 * defeat the common diff option "-s" which asked for
60 * DIFF_FORMAT_NO_OUTPUT.
61 */
62 if (revs->diffopt.output_format == DIFF_FORMAT_NO_OUTPUT)
63 revs->diffopt.output_format = DIFF_FORMAT_RAW;
64 return run_diff_files(revs, silent);
65}
66
67static void stuff_change(struct diff_options *opt,
68 unsigned old_mode, unsigned new_mode,
69 const unsigned char *old_sha1,
70 const unsigned char *new_sha1,
71 const char *old_name,
72 const char *new_name)
73{
74 struct diff_filespec *one, *two;
75
76 if (memcmp(null_sha1, old_sha1, 20) &&
77 memcmp(null_sha1, new_sha1, 20) &&
78 !memcmp(old_sha1, new_sha1, 20))
79 return;
80
81 if (opt->reverse_diff) {
82 unsigned tmp;
83 const
84 const unsigned char *tmp_u;
85 const char *tmp_c;
86 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
87 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
88 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
89 }
90 one = alloc_filespec(old_name);
91 two = alloc_filespec(new_name);
92 fill_filespec(one, old_sha1, old_mode);
93 fill_filespec(two, new_sha1, new_mode);
94
95 /* NEEDSWORK: shouldn't this part of diffopt??? */
96 diff_queue(&diff_queued_diff, one, two);
97}
98
99static int builtin_diff_b_f(struct rev_info *revs,
100 int argc, const char **argv,
101 struct blobinfo *blob,
102 const char *path)
103{
104 /* Blob vs file in the working tree*/
105 struct stat st;
106
107 while (1 < argc) {
108 const char *arg = argv[1];
109 if (!strcmp(arg, "--raw"))
110 revs->diffopt.output_format = DIFF_FORMAT_RAW;
111 else
112 usage(builtin_diff_usage);
113 argv++; argc--;
114 }
115 if (lstat(path, &st))
116 die("'%s': %s", path, strerror(errno));
117 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
118 die("'%s': not a regular file or symlink", path);
119 stuff_change(&revs->diffopt,
120 canon_mode(st.st_mode), canon_mode(st.st_mode),
121 blob[0].sha1, null_sha1,
122 blob[0].name, path);
123 diffcore_std(&revs->diffopt);
124 diff_flush(&revs->diffopt);
125 return 0;
126}
127
128static int builtin_diff_blobs(struct rev_info *revs,
129 int argc, const char **argv,
130 struct blobinfo *blob)
131{
132 /* Blobs */
133 unsigned mode = canon_mode(S_IFREG | 0644);
134
135 while (1 < argc) {
136 const char *arg = argv[1];
137 if (!strcmp(arg, "--raw"))
138 revs->diffopt.output_format = DIFF_FORMAT_RAW;
139 else
140 usage(builtin_diff_usage);
141 argv++; argc--;
142 }
143 stuff_change(&revs->diffopt,
144 mode, mode,
145 blob[0].sha1, blob[1].sha1,
146 blob[1].name, blob[1].name);
147 diffcore_std(&revs->diffopt);
148 diff_flush(&revs->diffopt);
149 return 0;
150}
151
152static int builtin_diff_index(struct rev_info *revs,
153 int argc, const char **argv)
154{
155 int cached = 0;
156 while (1 < argc) {
157 const char *arg = argv[1];
158 if (!strcmp(arg, "--cached"))
159 cached = 1;
160 else if (!strcmp(arg, "--raw"))
161 revs->diffopt.output_format = DIFF_FORMAT_RAW;
162 else
163 usage(builtin_diff_usage);
164 argv++; argc--;
165 }
166 /*
167 * Make sure there is one revision (i.e. pending object),
168 * and there is no revision filtering parameters.
169 */
170 if (!revs->pending_objects || revs->pending_objects->next ||
171 revs->max_count != -1 || revs->min_age != -1 ||
172 revs->max_age != -1)
173 usage(builtin_diff_usage);
174 return run_diff_index(revs, cached);
175}
176
177static int builtin_diff_tree(struct rev_info *revs,
178 int argc, const char **argv,
179 struct object_list *ent)
180{
181 /* We saw two trees, ent[0] and ent[1].
182 * unless ent[0] is unintesting, they are swapped
183 */
184 const unsigned char *(sha1[2]);
185 int swap = 1;
186 while (1 < argc) {
187 const char *arg = argv[1];
188 if (!strcmp(arg, "--raw"))
189 revs->diffopt.output_format = DIFF_FORMAT_RAW;
190 else
191 usage(builtin_diff_usage);
192 argv++; argc--;
193 }
194 if (ent[0].item->flags & UNINTERESTING)
195 swap = 0;
196 sha1[swap] = ent[0].item->sha1;
197 sha1[1-swap] = ent[1].item->sha1;
198 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
199 log_tree_diff_flush(revs);
200 return 0;
201}
202
203static void add_head(struct rev_info *revs)
204{
205 unsigned char sha1[20];
206 struct object *obj;
207 if (get_sha1("HEAD", sha1))
208 return;
209 obj = parse_object(sha1);
210 if (!obj)
211 return;
212 add_object(obj, &revs->pending_objects, NULL, "HEAD");
213}
214
215int cmd_diff(int argc, const char **argv, char **envp)
216{
217 struct rev_info rev;
218 struct object_list *list, ent[2];
219 int ents = 0, blobs = 0, paths = 0;
220 const char *path = NULL;
221 struct blobinfo blob[2];
222
223 /*
224 * We could get N tree-ish in the rev.pending_objects list.
225 * Also there could be M blobs there, and P pathspecs.
226 *
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.
233 *
234 * N=1, M=0:
235 * tree vs cache (diff-index --cached)
236 *
237 * N=2, M=0:
238 * tree vs tree (diff-tree)
239 *
240 * Other cases are errors.
241 */
242
243 git_config(git_diff_config);
244 init_revisions(&rev);
245 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
246
247 argc = setup_revisions(argc, argv, &rev, NULL);
248 /* Do we have --cached and not have a pending object, then
249 * default to HEAD by hand. Eek.
250 */
251 if (!rev.pending_objects) {
252 int i;
253 for (i = 1; i < argc; i++) {
254 const char *arg = argv[i];
255 if (!strcmp(arg, "--"))
256 break;
257 else if (!strcmp(arg, "--cached")) {
258 add_head(&rev);
259 break;
260 }
261 }
262 }
263
264 for (list = rev.pending_objects; list; list = list->next) {
265 struct object *obj = list->item;
266 const char *name = list->name;
267 int flags = (obj->flags & UNINTERESTING);
268 if (!obj->parsed)
269 obj = parse_object(obj->sha1);
270 obj = deref_tag(obj, NULL, 0);
271 if (!obj)
272 die("invalid object '%s' given.", name);
273 if (!strcmp(obj->type, commit_type))
274 obj = &((struct commit *)obj)->tree->object;
275 if (!strcmp(obj->type, tree_type)) {
276 if (2 <= ents)
277 die("more than two trees given: '%s'", name);
278 obj->flags |= flags;
279 ent[ents].item = obj;
280 ent[ents].name = name;
281 ents++;
282 continue;
283 }
284 if (!strcmp(obj->type, blob_type)) {
285 if (2 <= blobs)
286 die("more than two blobs given: '%s'", name);
287 memcpy(blob[blobs].sha1, obj->sha1, 20);
288 blob[blobs].name = name;
289 blobs++;
290 continue;
291
292 }
293 die("unhandled object '%s' given.", name);
294 }
295 if (rev.prune_data) {
296 const char **pathspec = rev.prune_data;
297 while (*pathspec) {
298 if (!path)
299 path = *pathspec;
300 paths++;
301 pathspec++;
302 }
303 }
304
305 /*
306 * Now, do the arguments look reasonable?
307 */
308 if (!ents) {
309 switch (blobs) {
310 case 0:
311 return builtin_diff_files(&rev, argc, argv);
312 break;
313 case 1:
314 if (paths != 1)
315 usage(builtin_diff_usage);
316 return builtin_diff_b_f(&rev, argc, argv, blob, path);
317 break;
318 case 2:
319 return builtin_diff_blobs(&rev, argc, argv, blob);
320 break;
321 default:
322 usage(builtin_diff_usage);
323 }
324 }
325 else if (blobs)
326 usage(builtin_diff_usage);
327 else if (ents == 1)
328 return builtin_diff_index(&rev, argc, argv);
329 else if (ents == 2)
330 return builtin_diff_tree(&rev, argc, argv, ent);
331 usage(builtin_diff_usage);
332}