Support 'diff=pgm' attribute
[git/git.git] / builtin-diff.c
CommitLineData
65056021
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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[] =
15e593e4 26"git-diff <options> <rev>{0,2} -- <path>*";
65056021 27
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28static void stuff_change(struct diff_options *opt,
29 unsigned old_mode, unsigned new_mode,
30 const unsigned char *old_sha1,
31 const unsigned char *new_sha1,
32 const char *old_name,
33 const char *new_name)
34{
35 struct diff_filespec *one, *two;
36
0bef57ee 37 if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
a89fccd2 38 !hashcmp(old_sha1, new_sha1))
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39 return;
40
41 if (opt->reverse_diff) {
42 unsigned tmp;
d92f1dc6 43 const unsigned char *tmp_u;
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44 const char *tmp_c;
45 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
46 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
47 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
48 }
49 one = alloc_filespec(old_name);
50 two = alloc_filespec(new_name);
51 fill_filespec(one, old_sha1, old_mode);
52 fill_filespec(two, new_sha1, new_mode);
53
54 /* NEEDSWORK: shouldn't this part of diffopt??? */
55 diff_queue(&diff_queued_diff, one, two);
56}
57
58static int builtin_diff_b_f(struct rev_info *revs,
59 int argc, const char **argv,
60 struct blobinfo *blob,
61 const char *path)
62{
63 /* Blob vs file in the working tree*/
64 struct stat st;
65
a610786f
TH
66 if (argc > 1)
67 usage(builtin_diff_usage);
68
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69 if (lstat(path, &st))
70 die("'%s': %s", path, strerror(errno));
71 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
72 die("'%s': not a regular file or symlink", path);
73 stuff_change(&revs->diffopt,
74 canon_mode(st.st_mode), canon_mode(st.st_mode),
75 blob[0].sha1, null_sha1,
065e0b12 76 path, path);
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77 diffcore_std(&revs->diffopt);
78 diff_flush(&revs->diffopt);
79 return 0;
80}
81
82static int builtin_diff_blobs(struct rev_info *revs,
83 int argc, const char **argv,
84 struct blobinfo *blob)
85{
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86 unsigned mode = canon_mode(S_IFREG | 0644);
87
a610786f
TH
88 if (argc > 1)
89 usage(builtin_diff_usage);
90
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91 stuff_change(&revs->diffopt,
92 mode, mode,
f82cd3c6 93 blob[0].sha1, blob[1].sha1,
53dd8a9c 94 blob[0].name, blob[1].name);
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95 diffcore_std(&revs->diffopt);
96 diff_flush(&revs->diffopt);
97 return 0;
98}
99
100static int builtin_diff_index(struct rev_info *revs,
101 int argc, const char **argv)
102{
103 int cached = 0;
104 while (1 < argc) {
105 const char *arg = argv[1];
f2dd1c9a 106 if (!strcmp(arg, "--cached"))
65056021 107 cached = 1;
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108 else
109 usage(builtin_diff_usage);
110 argv++; argc--;
111 }
112 /*
113 * Make sure there is one revision (i.e. pending object),
114 * and there is no revision filtering parameters.
115 */
1f1e895f 116 if (revs->pending.nr != 1 ||
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117 revs->max_count != -1 || revs->min_age != -1 ||
118 revs->max_age != -1)
119 usage(builtin_diff_usage);
b4e1e4a7
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120 if (read_cache() < 0) {
121 perror("read_cache");
122 return -1;
123 }
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124 return run_diff_index(revs, cached);
125}
126
127static int builtin_diff_tree(struct rev_info *revs,
128 int argc, const char **argv,
1f1e895f 129 struct object_array_entry *ent)
65056021 130{
65056021 131 const unsigned char *(sha1[2]);
1f1e895f 132 int swap = 0;
a610786f
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133
134 if (argc > 1)
135 usage(builtin_diff_usage);
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136
137 /* We saw two trees, ent[0] and ent[1].
82e5a82f 138 * if ent[1] is uninteresting, they are swapped
0fe7c1de 139 */
1f1e895f
LT
140 if (ent[1].item->flags & UNINTERESTING)
141 swap = 1;
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142 sha1[swap] = ent[0].item->sha1;
143 sha1[1-swap] = ent[1].item->sha1;
144 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
145 log_tree_diff_flush(revs);
146 return 0;
147}
148
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149static int builtin_diff_combined(struct rev_info *revs,
150 int argc, const char **argv,
1f1e895f 151 struct object_array_entry *ent,
0fe7c1de
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152 int ents)
153{
154 const unsigned char (*parent)[20];
155 int i;
156
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157 if (argc > 1)
158 usage(builtin_diff_usage);
159
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160 if (!revs->dense_combined_merges && !revs->combine_merges)
161 revs->dense_combined_merges = revs->combine_merges = 1;
162 parent = xmalloc(ents * sizeof(*parent));
163 /* Again, the revs are all reverse */
164 for (i = 0; i < ents; i++)
75b62b48
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165 hashcpy((unsigned char *)(parent + i),
166 ent[ents - 1 - i].item->sha1);
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167 diff_tree_combined(parent[0], parent + 1, ents - 1,
168 revs->dense_combined_merges, revs);
169 return 0;
170}
171
e686eb98 172void add_head(struct rev_info *revs)
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173{
174 unsigned char sha1[20];
175 struct object *obj;
176 if (get_sha1("HEAD", sha1))
177 return;
178 obj = parse_object(sha1);
179 if (!obj)
180 return;
1f1e895f 181 add_pending_object(revs, obj, "HEAD");
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182}
183
a633fca0 184int cmd_diff(int argc, const char **argv, const char *prefix)
65056021 185{
1f1e895f 186 int i;
65056021 187 struct rev_info rev;
1f1e895f 188 struct object_array_entry ent[100];
65056021 189 int ents = 0, blobs = 0, paths = 0;
a633fca0 190 const char *path = NULL;
65056021 191 struct blobinfo blob[2];
d516c2d1 192 int nongit = 0;
41bbf9d5 193 int result = 0;
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194
195 /*
196 * We could get N tree-ish in the rev.pending_objects list.
197 * Also there could be M blobs there, and P pathspecs.
198 *
199 * N=0, M=0:
200 * cache vs files (diff-files)
201 * N=0, M=2:
202 * compare two random blobs. P must be zero.
203 * N=0, M=1, P=1:
204 * compare a blob with a working tree file.
205 *
206 * N=1, M=0:
207 * tree vs cache (diff-index --cached)
208 *
209 * N=2, M=0:
210 * tree vs tree (diff-tree)
211 *
212 * Other cases are errors.
213 */
230f544e 214
d516c2d1 215 prefix = setup_git_directory_gently(&nongit);
ef1d9c5a 216 git_config(git_diff_ui_config);
db6296a5 217 init_revisions(&rev, prefix);
65056021 218
fcfa33ec
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219 if (!setup_diff_no_index(&rev, argc, argv, nongit, prefix))
220 argc = 0;
221 else
222 argc = setup_revisions(argc, argv, &rev, NULL);
047fbe90 223 if (!rev.diffopt.output_format) {
c9b5ef99 224 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
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225 if (diff_setup_done(&rev.diffopt) < 0)
226 die("diff_setup_done failed");
047fbe90 227 }
f1af60bd 228 rev.diffopt.allow_external = 1;
c9b5ef99 229
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230 /* Do we have --cached and not have a pending object, then
231 * default to HEAD by hand. Eek.
232 */
1f1e895f 233 if (!rev.pending.nr) {
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234 int i;
235 for (i = 1; i < argc; i++) {
236 const char *arg = argv[i];
237 if (!strcmp(arg, "--"))
238 break;
239 else if (!strcmp(arg, "--cached")) {
240 add_head(&rev);
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241 if (!rev.pending.nr)
242 die("No HEAD commit to compare with (yet)");
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243 break;
244 }
245 }
246 }
247
1f1e895f
LT
248 for (i = 0; i < rev.pending.nr; i++) {
249 struct object_array_entry *list = rev.pending.objects+i;
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250 struct object *obj = list->item;
251 const char *name = list->name;
252 int flags = (obj->flags & UNINTERESTING);
253 if (!obj->parsed)
254 obj = parse_object(obj->sha1);
255 obj = deref_tag(obj, NULL, 0);
256 if (!obj)
257 die("invalid object '%s' given.", name);
1974632c 258 if (obj->type == OBJ_COMMIT)
65056021 259 obj = &((struct commit *)obj)->tree->object;
1974632c 260 if (obj->type == OBJ_TREE) {
0fe7c1de
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261 if (ARRAY_SIZE(ent) <= ents)
262 die("more than %d trees given: '%s'",
334b506a 263 (int) ARRAY_SIZE(ent), name);
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264 obj->flags |= flags;
265 ent[ents].item = obj;
266 ent[ents].name = name;
267 ents++;
268 continue;
269 }
1974632c 270 if (obj->type == OBJ_BLOB) {
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271 if (2 <= blobs)
272 die("more than two blobs given: '%s'", name);
e702496e 273 hashcpy(blob[blobs].sha1, obj->sha1);
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274 blob[blobs].name = name;
275 blobs++;
276 continue;
230f544e 277
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278 }
279 die("unhandled object '%s' given.", name);
280 }
281 if (rev.prune_data) {
282 const char **pathspec = rev.prune_data;
283 while (*pathspec) {
284 if (!path)
285 path = *pathspec;
286 paths++;
287 pathspec++;
288 }
289 }
290
291 /*
292 * Now, do the arguments look reasonable?
293 */
294 if (!ents) {
295 switch (blobs) {
296 case 0:
41bbf9d5 297 result = run_diff_files_cmd(&rev, argc, argv);
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298 break;
299 case 1:
300 if (paths != 1)
301 usage(builtin_diff_usage);
41bbf9d5 302 result = builtin_diff_b_f(&rev, argc, argv, blob, path);
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303 break;
304 case 2:
0fe7c1de
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305 if (paths)
306 usage(builtin_diff_usage);
41bbf9d5 307 result = builtin_diff_blobs(&rev, argc, argv, blob);
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308 break;
309 default:
310 usage(builtin_diff_usage);
311 }
312 }
313 else if (blobs)
314 usage(builtin_diff_usage);
315 else if (ents == 1)
41bbf9d5 316 result = builtin_diff_index(&rev, argc, argv);
65056021 317 else if (ents == 2)
41bbf9d5 318 result = builtin_diff_tree(&rev, argc, argv, ent);
9919f41c
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319 else if ((ents == 3) && (ent[0].item->flags & UNINTERESTING)) {
320 /* diff A...B where there is one sane merge base between
321 * A and B. We have ent[0] == merge-base, ent[1] == A,
322 * and ent[2] == B. Show diff between the base and B.
323 */
306ea2df 324 ent[1] = ent[2];
41bbf9d5 325 result = builtin_diff_tree(&rev, argc, argv, ent);
9919f41c 326 }
0fe7c1de 327 else
41bbf9d5 328 result = builtin_diff_combined(&rev, argc, argv,
9919f41c 329 ent, ents);
41bbf9d5
AR
330 if (rev.diffopt.exit_with_status)
331 result = rev.diffopt.has_changes;
332 return result;
65056021 333}