1/*
2 * Builtin "git diff"
3 *
4 * Copyright (c) 2006 Junio C Hamano
5 */
6#include "cache.h"
7#include "color.h"
8#include "commit.h"
9#include "blob.h"
10#include "tag.h"
11#include "diff.h"
12#include "diffcore.h"
13#include "revision.h"
14#include "log-tree.h"
15#include "builtin.h"
16#include "submodule.h"
17#include "sha1-array.h"
18struct blobinfo {
20 unsigned char sha1[20];
21 const char *name;
22 unsigned mode;
23};
24static const char builtin_diff_usage[] =
26"git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
27static 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 int old_sha1_valid,
33 int new_sha1_valid,
34 const char *old_name,
35 const char *new_name)
36{
37 struct diff_filespec *one, *two;
38 if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
40 !hashcmp(old_sha1, new_sha1) && (old_mode == new_mode))
41 return;
42 if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
44 unsigned tmp;
45 const unsigned char *tmp_u;
46 const char *tmp_c;
47 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
48 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
49 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
50 }
51 if (opt->prefix &&
53 (strncmp(old_name, opt->prefix, opt->prefix_length) ||
54 strncmp(new_name, opt->prefix, opt->prefix_length)))
55 return;
56 one = alloc_filespec(old_name);
58 two = alloc_filespec(new_name);
59 fill_filespec(one, old_sha1, old_sha1_valid, old_mode);
60 fill_filespec(two, new_sha1, new_sha1_valid, new_mode);
61 diff_queue(&diff_queued_diff, one, two);
63}
64static int builtin_diff_b_f(struct rev_info *revs,
66 int argc, const char **argv,
67 struct blobinfo *blob,
68 const char *path)
69{
70 /* Blob vs file in the working tree*/
71 struct stat st;
72 if (argc > 1)
74 usage(builtin_diff_usage);
75 if (lstat(path, &st))
77 die_errno(_("failed to stat '%s'"), path);
78 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
79 die(_("'%s': not a regular file or symlink"), path);
80 diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
82 if (blob[0].mode == S_IFINVALID)
84 blob[0].mode = canon_mode(st.st_mode);
85 stuff_change(&revs->diffopt,
87 blob[0].mode, canon_mode(st.st_mode),
88 blob[0].sha1, null_sha1,
89 1, 0,
90 path, path);
91 diffcore_std(&revs->diffopt);
92 diff_flush(&revs->diffopt);
93 return 0;
94}
95static int builtin_diff_blobs(struct rev_info *revs,
97 int argc, const char **argv,
98 struct blobinfo *blob)
99{
100 unsigned mode = canon_mode(S_IFREG | 0644);
101 if (argc > 1)
103 usage(builtin_diff_usage);
104 if (blob[0].mode == S_IFINVALID)
106 blob[0].mode = mode;
107 if (blob[1].mode == S_IFINVALID)
109 blob[1].mode = mode;
110 stuff_change(&revs->diffopt,
112 blob[0].mode, blob[1].mode,
113 blob[0].sha1, blob[1].sha1,
114 1, 1,
115 blob[0].name, blob[1].name);
116 diffcore_std(&revs->diffopt);
117 diff_flush(&revs->diffopt);
118 return 0;
119}
120static int builtin_diff_index(struct rev_info *revs,
122 int argc, const char **argv)
123{
124 int cached = 0;
125 while (1 < argc) {
126 const char *arg = argv[1];
127 if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
128 cached = 1;
129 else
130 usage(builtin_diff_usage);
131 argv++; argc--;
132 }
133 /*
134 * Make sure there is one revision (i.e. pending object),
135 * and there is no revision filtering parameters.
136 */
137 if (revs->pending.nr != 1 ||
138 revs->max_count != -1 || revs->min_age != -1 ||
139 revs->max_age != -1)
140 usage(builtin_diff_usage);
141 if (!cached) {
142 setup_work_tree();
143 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
144 perror("read_cache_preload");
145 return -1;
146 }
147 } else if (read_cache() < 0) {
148 perror("read_cache");
149 return -1;
150 }
151 return run_diff_index(revs, cached);
152}
153static int builtin_diff_tree(struct rev_info *revs,
155 int argc, const char **argv,
156 struct object_array_entry *ent0,
157 struct object_array_entry *ent1)
158{
159 const unsigned char *(sha1[2]);
160 int swap = 0;
161 if (argc > 1)
163 usage(builtin_diff_usage);
164 /*
166 * We saw two trees, ent0 and ent1. If ent1 is uninteresting,
167 * swap them.
168 */
169 if (ent1->item->flags & UNINTERESTING)
170 swap = 1;
171 sha1[swap] = ent0->item->sha1;
172 sha1[1-swap] = ent1->item->sha1;
173 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
174 log_tree_diff_flush(revs);
175 return 0;
176}
177static int builtin_diff_combined(struct rev_info *revs,
179 int argc, const char **argv,
180 struct object_array_entry *ent,
181 int ents)
182{
183 struct sha1_array parents = SHA1_ARRAY_INIT;
184 int i;
185 if (argc > 1)
187 usage(builtin_diff_usage);
188 if (!revs->dense_combined_merges && !revs->combine_merges)
190 revs->dense_combined_merges = revs->combine_merges = 1;
191 for (i = 1; i < ents; i++)
192 sha1_array_append(&parents, ent[i].item->sha1);
193 diff_tree_combined(ent[0].item->sha1, &parents,
194 revs->dense_combined_merges, revs);
195 sha1_array_clear(&parents);
196 return 0;
197}
198static void refresh_index_quietly(void)
200{
201 struct lock_file *lock_file;
202 int fd;
203 lock_file = xcalloc(1, sizeof(struct lock_file));
205 fd = hold_locked_index(lock_file, 0);
206 if (fd < 0)
207 return;
208 discard_cache();
209 read_cache();
210 refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
211 update_index_if_able(&the_index, lock_file);
212}
213static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
215{
216 unsigned int options = 0;
217 while (1 < argc && argv[1][0] == '-') {
219 if (!strcmp(argv[1], "--base"))
220 revs->max_count = 1;
221 else if (!strcmp(argv[1], "--ours"))
222 revs->max_count = 2;
223 else if (!strcmp(argv[1], "--theirs"))
224 revs->max_count = 3;
225 else if (!strcmp(argv[1], "-q"))
226 options |= DIFF_SILENT_ON_REMOVED;
227 else if (!strcmp(argv[1], "-h"))
228 usage(builtin_diff_usage);
229 else
230 return error(_("invalid option: %s"), argv[1]);
231 argv++; argc--;
232 }
233 /*
235 * "diff --base" should not combine merges because it was not
236 * asked to. "diff -c" should not densify (if the user wants
237 * dense one, --cc can be explicitly asked for, or just rely
238 * on the default).
239 */
240 if (revs->max_count == -1 && !revs->combine_merges &&
241 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
242 revs->combine_merges = revs->dense_combined_merges = 1;
243 setup_work_tree();
245 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
246 perror("read_cache_preload");
247 return -1;
248 }
249 return run_diff_files(revs, options);
250}
251int cmd_diff(int argc, const char **argv, const char *prefix)
253{
254 int i;
255 struct rev_info rev;
256 struct object_array ent = OBJECT_ARRAY_INIT;
257 int blobs = 0, paths = 0;
258 const char *path = NULL;
259 struct blobinfo blob[2];
260 int nongit;
261 int result = 0;
262 /*
264 * We could get N tree-ish in the rev.pending_objects list.
265 * Also there could be M blobs there, and P pathspecs.
266 *
267 * N=0, M=0:
268 * cache vs files (diff-files)
269 * N=0, M=2:
270 * compare two random blobs. P must be zero.
271 * N=0, M=1, P=1:
272 * compare a blob with a working tree file.
273 *
274 * N=1, M=0:
275 * tree vs cache (diff-index --cached)
276 *
277 * N=2, M=0:
278 * tree vs tree (diff-tree)
279 *
280 * N=0, M=0, P=2:
281 * compare two filesystem entities (aka --no-index).
282 *
283 * Other cases are errors.
284 */
285 prefix = setup_git_directory_gently(&nongit);
287 gitmodules_config();
288 git_config(git_diff_ui_config, NULL);
289 init_revisions(&rev, prefix);
291 /* If this is a no-index diff, just run it and exit there. */
293 diff_no_index(&rev, argc, argv, nongit, prefix);
294 /* Otherwise, we are doing the usual "git" diff */
296 rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
297 /* Scale to real terminal size and respect statGraphWidth config */
299 rev.diffopt.stat_width = -1;
300 rev.diffopt.stat_graph_width = -1;
301 /* Default to let external and textconv be used */
303 DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
304 DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
305 if (nongit)
307 die(_("Not a git repository"));
308 argc = setup_revisions(argc, argv, &rev, NULL);
309 if (!rev.diffopt.output_format) {
310 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
311 diff_setup_done(&rev.diffopt);
312 }
313 DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
315 setup_diff_pager(&rev.diffopt);
317 /*
319 * Do we have --cached and not have a pending object, then
320 * default to HEAD by hand. Eek.
321 */
322 if (!rev.pending.nr) {
323 int i;
324 for (i = 1; i < argc; i++) {
325 const char *arg = argv[i];
326 if (!strcmp(arg, "--"))
327 break;
328 else if (!strcmp(arg, "--cached") ||
329 !strcmp(arg, "--staged")) {
330 add_head_to_pending(&rev);
331 if (!rev.pending.nr) {
332 struct tree *tree;
333 tree = lookup_tree(EMPTY_TREE_SHA1_BIN);
334 add_pending_object(&rev, &tree->object, "HEAD");
335 }
336 break;
337 }
338 }
339 }
340 for (i = 0; i < rev.pending.nr; i++) {
342 struct object_array_entry *entry = &rev.pending.objects[i];
343 struct object *obj = entry->item;
344 const char *name = entry->name;
345 int flags = (obj->flags & UNINTERESTING);
346 if (!obj->parsed)
347 obj = parse_object(obj->sha1);
348 obj = deref_tag(obj, NULL, 0);
349 if (!obj)
350 die(_("invalid object '%s' given."), name);
351 if (obj->type == OBJ_COMMIT)
352 obj = &((struct commit *)obj)->tree->object;
353 if (obj->type == OBJ_TREE) {
355 obj->flags |= flags;
356 add_object_array(obj, name, &ent);
357 } else if (obj->type == OBJ_BLOB) {
358 if (2 <= blobs)
359 die(_("more than two blobs given: '%s'"), name);
360 hashcpy(blob[blobs].sha1, obj->sha1);
361 blob[blobs].name = name;
362 blob[blobs].mode = entry->mode;
363 blobs++;
364 } else {
366 die(_("unhandled object '%s' given."), name);
367 }
368 }
369 if (rev.prune_data.nr) {
370 /* builtin_diff_b_f() */
371 GUARD_PATHSPEC(&rev.prune_data, PATHSPEC_FROMTOP | PATHSPEC_LITERAL);
372 if (!path)
373 path = rev.prune_data.items[0].match;
374 paths += rev.prune_data.nr;
375 }
376 /*
378 * Now, do the arguments look reasonable?
379 */
380 if (!ent.nr) {
381 switch (blobs) {
382 case 0:
383 result = builtin_diff_files(&rev, argc, argv);
384 break;
385 case 1:
386 if (paths != 1)
387 usage(builtin_diff_usage);
388 result = builtin_diff_b_f(&rev, argc, argv, blob, path);
389 break;
390 case 2:
391 if (paths)
392 usage(builtin_diff_usage);
393 result = builtin_diff_blobs(&rev, argc, argv, blob);
394 break;
395 default:
396 usage(builtin_diff_usage);
397 }
398 }
399 else if (blobs)
400 usage(builtin_diff_usage);
401 else if (ent.nr == 1)
402 result = builtin_diff_index(&rev, argc, argv);
403 else if (ent.nr == 2)
404 result = builtin_diff_tree(&rev, argc, argv,
405 &ent.objects[0], &ent.objects[1]);
406 else if (ent.objects[0].item->flags & UNINTERESTING) {
407 /*
408 * diff A...B where there is at least one merge base
409 * between A and B. We have ent.objects[0] ==
410 * merge-base, ent.objects[ents-2] == A, and
411 * ent.objects[ents-1] == B. Show diff between the
412 * base and B. Note that we pick one merge base at
413 * random if there are more than one.
414 */
415 result = builtin_diff_tree(&rev, argc, argv,
416 &ent.objects[0],
417 &ent.objects[ent.nr-1]);
418 } else
419 result = builtin_diff_combined(&rev, argc, argv,
420 ent.objects, ent.nr);
421 result = diff_result_code(&rev.diffopt, result);
422 if (1 < rev.diffopt.skip_stat_unmatch)
423 refresh_index_quietly();
424 return result;
425}