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{
69 /* Blob vs file in the working tree*/
70 struct stat st;
71 const char *path;
72 if (argc > 1)
74 usage(builtin_diff_usage);
75 GUARD_PATHSPEC(&revs->prune_data, PATHSPEC_FROMTOP | PATHSPEC_LITERAL);
77 path = revs->prune_data.items[0].match;
78 if (lstat(path, &st))
80 die_errno(_("failed to stat '%s'"), path);
81 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
82 die(_("'%s': not a regular file or symlink"), path);
83 diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
85 if (blob[0].mode == S_IFINVALID)
87 blob[0].mode = canon_mode(st.st_mode);
88 stuff_change(&revs->diffopt,
90 blob[0].mode, canon_mode(st.st_mode),
91 blob[0].sha1, null_sha1,
92 1, 0,
93 path, path);
94 diffcore_std(&revs->diffopt);
95 diff_flush(&revs->diffopt);
96 return 0;
97}
98static int builtin_diff_blobs(struct rev_info *revs,
100 int argc, const char **argv,
101 struct blobinfo *blob)
102{
103 unsigned mode = canon_mode(S_IFREG | 0644);
104 if (argc > 1)
106 usage(builtin_diff_usage);
107 if (blob[0].mode == S_IFINVALID)
109 blob[0].mode = mode;
110 if (blob[1].mode == S_IFINVALID)
112 blob[1].mode = mode;
113 stuff_change(&revs->diffopt,
115 blob[0].mode, blob[1].mode,
116 blob[0].sha1, blob[1].sha1,
117 1, 1,
118 blob[0].name, blob[1].name);
119 diffcore_std(&revs->diffopt);
120 diff_flush(&revs->diffopt);
121 return 0;
122}
123static int builtin_diff_index(struct rev_info *revs,
125 int argc, const char **argv)
126{
127 int cached = 0;
128 while (1 < argc) {
129 const char *arg = argv[1];
130 if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
131 cached = 1;
132 else
133 usage(builtin_diff_usage);
134 argv++; argc--;
135 }
136 /*
137 * Make sure there is one revision (i.e. pending object),
138 * and there is no revision filtering parameters.
139 */
140 if (revs->pending.nr != 1 ||
141 revs->max_count != -1 || revs->min_age != -1 ||
142 revs->max_age != -1)
143 usage(builtin_diff_usage);
144 if (!cached) {
145 setup_work_tree();
146 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
147 perror("read_cache_preload");
148 return -1;
149 }
150 } else if (read_cache() < 0) {
151 perror("read_cache");
152 return -1;
153 }
154 return run_diff_index(revs, cached);
155}
156static int builtin_diff_tree(struct rev_info *revs,
158 int argc, const char **argv,
159 struct object_array_entry *ent0,
160 struct object_array_entry *ent1)
161{
162 const unsigned char *(sha1[2]);
163 int swap = 0;
164 if (argc > 1)
166 usage(builtin_diff_usage);
167 /*
169 * We saw two trees, ent0 and ent1. If ent1 is uninteresting,
170 * swap them.
171 */
172 if (ent1->item->flags & UNINTERESTING)
173 swap = 1;
174 sha1[swap] = ent0->item->sha1;
175 sha1[1 - swap] = ent1->item->sha1;
176 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
177 log_tree_diff_flush(revs);
178 return 0;
179}
180static int builtin_diff_combined(struct rev_info *revs,
182 int argc, const char **argv,
183 struct object_array_entry *ent,
184 int ents)
185{
186 struct sha1_array parents = SHA1_ARRAY_INIT;
187 int i;
188 if (argc > 1)
190 usage(builtin_diff_usage);
191 if (!revs->dense_combined_merges && !revs->combine_merges)
193 revs->dense_combined_merges = revs->combine_merges = 1;
194 for (i = 1; i < ents; i++)
195 sha1_array_append(&parents, ent[i].item->sha1);
196 diff_tree_combined(ent[0].item->sha1, &parents,
197 revs->dense_combined_merges, revs);
198 sha1_array_clear(&parents);
199 return 0;
200}
201static void refresh_index_quietly(void)
203{
204 struct lock_file *lock_file;
205 int fd;
206 lock_file = xcalloc(1, sizeof(struct lock_file));
208 fd = hold_locked_index(lock_file, 0);
209 if (fd < 0)
210 return;
211 discard_cache();
212 read_cache();
213 refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
214 update_index_if_able(&the_index, lock_file);
215}
216static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
218{
219 unsigned int options = 0;
220 while (1 < argc && argv[1][0] == '-') {
222 if (!strcmp(argv[1], "--base"))
223 revs->max_count = 1;
224 else if (!strcmp(argv[1], "--ours"))
225 revs->max_count = 2;
226 else if (!strcmp(argv[1], "--theirs"))
227 revs->max_count = 3;
228 else if (!strcmp(argv[1], "-q"))
229 options |= DIFF_SILENT_ON_REMOVED;
230 else if (!strcmp(argv[1], "-h"))
231 usage(builtin_diff_usage);
232 else
233 return error(_("invalid option: %s"), argv[1]);
234 argv++; argc--;
235 }
236 /*
238 * "diff --base" should not combine merges because it was not
239 * asked to. "diff -c" should not densify (if the user wants
240 * dense one, --cc can be explicitly asked for, or just rely
241 * on the default).
242 */
243 if (revs->max_count == -1 && !revs->combine_merges &&
244 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
245 revs->combine_merges = revs->dense_combined_merges = 1;
246 setup_work_tree();
248 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
249 perror("read_cache_preload");
250 return -1;
251 }
252 return run_diff_files(revs, options);
253}
254int cmd_diff(int argc, const char **argv, const char *prefix)
256{
257 int i;
258 struct rev_info rev;
259 struct object_array ent = OBJECT_ARRAY_INIT;
260 int blobs = 0, paths = 0;
261 struct blobinfo blob[2];
262 int nongit;
263 int result = 0;
264 /*
266 * We could get N tree-ish in the rev.pending_objects list.
267 * Also there could be M blobs there, and P pathspecs.
268 *
269 * N=0, M=0:
270 * cache vs files (diff-files)
271 * N=0, M=2:
272 * compare two random blobs. P must be zero.
273 * N=0, M=1, P=1:
274 * compare a blob with a working tree file.
275 *
276 * N=1, M=0:
277 * tree vs cache (diff-index --cached)
278 *
279 * N=2, M=0:
280 * tree vs tree (diff-tree)
281 *
282 * N=0, M=0, P=2:
283 * compare two filesystem entities (aka --no-index).
284 *
285 * Other cases are errors.
286 */
287 prefix = setup_git_directory_gently(&nongit);
289 gitmodules_config();
290 git_config(git_diff_ui_config, NULL);
291 init_revisions(&rev, prefix);
293 /* If this is a no-index diff, just run it and exit there. */
295 diff_no_index(&rev, argc, argv, nongit, prefix);
296 /* Otherwise, we are doing the usual "git" diff */
298 rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
299 /* Scale to real terminal size and respect statGraphWidth config */
301 rev.diffopt.stat_width = -1;
302 rev.diffopt.stat_graph_width = -1;
303 /* Default to let external and textconv be used */
305 DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
306 DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
307 if (nongit)
309 die(_("Not a git repository"));
310 argc = setup_revisions(argc, argv, &rev, NULL);
311 if (!rev.diffopt.output_format) {
312 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
313 diff_setup_done(&rev.diffopt);
314 }
315 DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
317 setup_diff_pager(&rev.diffopt);
319 /*
321 * Do we have --cached and not have a pending object, then
322 * default to HEAD by hand. Eek.
323 */
324 if (!rev.pending.nr) {
325 int i;
326 for (i = 1; i < argc; i++) {
327 const char *arg = argv[i];
328 if (!strcmp(arg, "--"))
329 break;
330 else if (!strcmp(arg, "--cached") ||
331 !strcmp(arg, "--staged")) {
332 add_head_to_pending(&rev);
333 if (!rev.pending.nr) {
334 struct tree *tree;
335 tree = lookup_tree(EMPTY_TREE_SHA1_BIN);
336 add_pending_object(&rev, &tree->object, "HEAD");
337 }
338 break;
339 }
340 }
341 }
342 for (i = 0; i < rev.pending.nr; i++) {
344 struct object_array_entry *entry = &rev.pending.objects[i];
345 struct object *obj = entry->item;
346 const char *name = entry->name;
347 int flags = (obj->flags & UNINTERESTING);
348 if (!obj->parsed)
349 obj = parse_object(obj->sha1);
350 obj = deref_tag(obj, NULL, 0);
351 if (!obj)
352 die(_("invalid object '%s' given."), name);
353 if (obj->type == OBJ_COMMIT)
354 obj = &((struct commit *)obj)->tree->object;
355 if (obj->type == OBJ_TREE) {
357 obj->flags |= flags;
358 add_object_array(obj, name, &ent);
359 } else if (obj->type == OBJ_BLOB) {
360 if (2 <= blobs)
361 die(_("more than two blobs given: '%s'"), name);
362 hashcpy(blob[blobs].sha1, obj->sha1);
363 blob[blobs].name = name;
364 blob[blobs].mode = entry->mode;
365 blobs++;
366 } else {
368 die(_("unhandled object '%s' given."), name);
369 }
370 }
371 if (rev.prune_data.nr)
372 paths += rev.prune_data.nr;
373 /*
375 * Now, do the arguments look reasonable?
376 */
377 if (!ent.nr) {
378 switch (blobs) {
379 case 0:
380 result = builtin_diff_files(&rev, argc, argv);
381 break;
382 case 1:
383 if (paths != 1)
384 usage(builtin_diff_usage);
385 result = builtin_diff_b_f(&rev, argc, argv, blob);
386 break;
387 case 2:
388 if (paths)
389 usage(builtin_diff_usage);
390 result = builtin_diff_blobs(&rev, argc, argv, blob);
391 break;
392 default:
393 usage(builtin_diff_usage);
394 }
395 }
396 else if (blobs)
397 usage(builtin_diff_usage);
398 else if (ent.nr == 1)
399 result = builtin_diff_index(&rev, argc, argv);
400 else if (ent.nr == 2)
401 result = builtin_diff_tree(&rev, argc, argv,
402 &ent.objects[0], &ent.objects[1]);
403 else if (ent.objects[0].item->flags & UNINTERESTING) {
404 /*
405 * diff A...B where there is at least one merge base
406 * between A and B. We have ent.objects[0] ==
407 * merge-base, ent.objects[ents-2] == A, and
408 * ent.objects[ents-1] == B. Show diff between the
409 * base and B. Note that we pick one merge base at
410 * random if there are more than one.
411 */
412 result = builtin_diff_tree(&rev, argc, argv,
413 &ent.objects[0],
414 &ent.objects[ent.nr-1]);
415 } else
416 result = builtin_diff_combined(&rev, argc, argv,
417 ent.objects, ent.nr);
418 result = diff_result_code(&rev.diffopt, result);
419 if (1 < rev.diffopt.skip_stat_unmatch)
420 refresh_index_quietly();
421 return result;
422}