Fix a comparison bug in diff-delta.c
[git/git.git] / diff-lib.c
CommitLineData
be3cfa85
JH
1/*
2 * Copyright (C) 2005 Junio C Hamano
3 */
86436c28 4#include "cache.h"
6fb737be 5#include "quote.h"
6973dcae 6#include "commit.h"
86436c28 7#include "diff.h"
427dcb4b 8#include "diffcore.h"
6973dcae 9#include "revision.h"
427dcb4b 10
b46f0b6d 11/*
6973dcae 12 * diff-files
b46f0b6d 13 */
f0c6b2a2 14
6973dcae 15int run_diff_files(struct rev_info *revs, int silent_on_removed)
f0c6b2a2 16{
6973dcae
JH
17 int entries, i;
18 int diff_unmerged_stage = revs->max_count;
f0c6b2a2 19
6973dcae
JH
20 if (diff_unmerged_stage < 0)
21 diff_unmerged_stage = 2;
22 entries = read_cache();
23 if (entries < 0) {
24 perror("read_cache");
427dcb4b 25 return -1;
427dcb4b 26 }
6973dcae 27 for (i = 0; i < entries; i++) {
be3cfa85 28 struct stat st;
6973dcae
JH
29 unsigned int oldmode, newmode;
30 struct cache_entry *ce = active_cache[i];
31 int changed;
8676eb43 32
6973dcae 33 if (!ce_path_match(ce, revs->prune_data))
8676eb43 34 continue;
be3cfa85 35
6973dcae 36 if (ce_stage(ce)) {
b4b15503 37 struct combine_diff_path *dpath;
6973dcae 38 int num_compare_stages = 0;
b4b15503 39 size_t path_len;
6973dcae 40
b4b15503
FF
41 path_len = ce_namelen(ce);
42
43 dpath = xmalloc (combine_diff_path_size (5, path_len));
44 dpath->path = (char *) &(dpath->parent[5]);
45
46 dpath->next = NULL;
47 dpath->len = path_len;
48 memcpy(dpath->path, ce->name, path_len);
49 dpath->path[path_len] = '\0';
50 dpath->mode = 0;
51 memset(dpath->sha1, 0, 20);
52 memset(&(dpath->parent[0]), 0,
53 sizeof(struct combine_diff_parent)*5);
6973dcae
JH
54
55 while (i < entries) {
56 struct cache_entry *nce = active_cache[i];
57 int stage;
58
59 if (strcmp(ce->name, nce->name))
60 break;
61
62 /* Stage #2 (ours) is the first parent,
63 * stage #3 (theirs) is the second.
64 */
65 stage = ce_stage(nce);
66 if (2 <= stage) {
67 int mode = ntohl(nce->ce_mode);
68 num_compare_stages++;
b4b15503 69 memcpy(dpath->parent[stage-2].sha1,
6973dcae 70 nce->sha1, 20);
b4b15503 71 dpath->parent[stage-2].mode =
6973dcae 72 canon_mode(mode);
b4b15503 73 dpath->parent[stage-2].status =
6973dcae
JH
74 DIFF_STATUS_MODIFIED;
75 }
76
77 /* diff against the proper unmerged stage */
78 if (stage == diff_unmerged_stage)
79 ce = nce;
80 i++;
81 }
82 /*
83 * Compensate for loop update
f0c6b2a2 84 */
6973dcae 85 i--;
6b5ee137 86
6973dcae 87 if (revs->combine_merges && num_compare_stages == 2) {
b4b15503 88 show_combined_diff(dpath, 2,
6973dcae
JH
89 revs->dense_combined_merges,
90 revs);
b4b15503 91 free(dpath);
6973dcae 92 continue;
1b1480ff 93 }
b4b15503
FF
94 free(dpath);
95 dpath = NULL;
0e3994fa 96
6973dcae
JH
97 /*
98 * Show the diff for the 'ce' if we found the one
99 * from the desired stage.
100 */
101 diff_unmerge(&revs->diffopt, ce->name);
102 if (ce_stage(ce) != diff_unmerged_stage)
103 continue;
eeaa4603 104 }
6b14d7fa 105
6973dcae
JH
106 if (lstat(ce->name, &st) < 0) {
107 if (errno != ENOENT && errno != ENOTDIR) {
108 perror(ce->name);
15d061b4
JH
109 continue;
110 }
6973dcae
JH
111 if (silent_on_removed)
112 continue;
113 diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
114 ce->sha1, ce->name, NULL);
115 continue;
f2ce9fde 116 }
6973dcae
JH
117 changed = ce_match_stat(ce, &st, 0);
118 if (!changed && !revs->diffopt.find_copies_harder)
119 continue;
120 oldmode = ntohl(ce->ce_mode);
be3cfa85 121
6973dcae
JH
122 newmode = canon_mode(st.st_mode);
123 if (!trust_executable_bit &&
124 S_ISREG(newmode) && S_ISREG(oldmode) &&
125 ((newmode ^ oldmode) == 0111))
126 newmode = oldmode;
127 diff_change(&revs->diffopt, oldmode, newmode,
128 ce->sha1, (changed ? null_sha1 : ce->sha1),
129 ce->name, NULL);
77eb2720 130
7ca45252 131 }
6973dcae
JH
132 diffcore_std(&revs->diffopt);
133 diff_flush(&revs->diffopt);
134 return 0;
77eb2720 135}
be3cfa85 136
e09ad6e1
JH
137/*
138 * diff-index
139 */
140
141/* A file entry went away or appeared */
142static void diff_index_show_file(struct rev_info *revs,
143 const char *prefix,
144 struct cache_entry *ce,
145 unsigned char *sha1, unsigned int mode)
146{
147 diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
148 sha1, ce->name, NULL);
149}
150
151static int get_stat_data(struct cache_entry *ce,
152 unsigned char **sha1p,
153 unsigned int *modep,
154 int cached, int match_missing)
155{
156 unsigned char *sha1 = ce->sha1;
157 unsigned int mode = ce->ce_mode;
158
159 if (!cached) {
160 static unsigned char no_sha1[20];
161 int changed;
162 struct stat st;
163 if (lstat(ce->name, &st) < 0) {
164 if (errno == ENOENT && match_missing) {
165 *sha1p = sha1;
166 *modep = mode;
167 return 0;
168 }
169 return -1;
170 }
171 changed = ce_match_stat(ce, &st, 0);
172 if (changed) {
173 mode = create_ce_mode(st.st_mode);
174 if (!trust_executable_bit && S_ISREG(st.st_mode))
175 mode = ce->ce_mode;
176 sha1 = no_sha1;
177 }
178 }
179
180 *sha1p = sha1;
181 *modep = mode;
182 return 0;
183}
184
185static void show_new_file(struct rev_info *revs,
186 struct cache_entry *new,
187 int cached, int match_missing)
188{
189 unsigned char *sha1;
190 unsigned int mode;
191
192 /* New file in the index: it might actually be different in
193 * the working copy.
194 */
195 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
196 return;
197
198 diff_index_show_file(revs, "+", new, sha1, mode);
199}
200
201static int show_modified(struct rev_info *revs,
202 struct cache_entry *old,
203 struct cache_entry *new,
204 int report_missing,
205 int cached, int match_missing)
206{
207 unsigned int mode, oldmode;
208 unsigned char *sha1;
209
210 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
211 if (report_missing)
212 diff_index_show_file(revs, "-", old,
213 old->sha1, old->ce_mode);
214 return -1;
215 }
216
217 oldmode = old->ce_mode;
a89fccd2 218 if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
e09ad6e1
JH
219 !revs->diffopt.find_copies_harder)
220 return 0;
221
222 mode = ntohl(mode);
223 oldmode = ntohl(oldmode);
224
225 diff_change(&revs->diffopt, oldmode, mode,
226 old->sha1, sha1, old->name, NULL);
227 return 0;
228}
229
230static int diff_cache(struct rev_info *revs,
231 struct cache_entry **ac, int entries,
232 const char **pathspec,
233 int cached, int match_missing)
234{
235 while (entries) {
236 struct cache_entry *ce = *ac;
237 int same = (entries > 1) && ce_same_name(ce, ac[1]);
238
239 if (!ce_path_match(ce, pathspec))
240 goto skip_entry;
241
242 switch (ce_stage(ce)) {
243 case 0:
244 /* No stage 1 entry? That means it's a new file */
245 if (!same) {
246 show_new_file(revs, ce, cached, match_missing);
247 break;
248 }
249 /* Show difference between old and new */
250 show_modified(revs,ac[1], ce, 1,
251 cached, match_missing);
252 break;
253 case 1:
254 /* No stage 3 (merge) entry?
255 * That means it's been deleted.
256 */
257 if (!same) {
258 diff_index_show_file(revs, "-", ce,
259 ce->sha1, ce->ce_mode);
260 break;
261 }
262 /* We come here with ce pointing at stage 1
263 * (original tree) and ac[1] pointing at stage
264 * 3 (unmerged). show-modified with
265 * report-missing set to false does not say the
266 * file is deleted but reports true if work
267 * tree does not have it, in which case we
268 * fall through to report the unmerged state.
269 * Otherwise, we show the differences between
270 * the original tree and the work tree.
271 */
272 if (!cached &&
273 !show_modified(revs, ce, ac[1], 0,
274 cached, match_missing))
275 break;
276 /* fallthru */
277 case 3:
278 diff_unmerge(&revs->diffopt, ce->name);
279 break;
280
281 default:
282 die("impossible cache entry stage");
283 }
284
285skip_entry:
286 /*
287 * Ignore all the different stages for this file,
288 * we've handled the relevant cases now.
289 */
290 do {
291 ac++;
292 entries--;
293 } while (entries && ce_same_name(ce, ac[0]));
294 }
295 return 0;
296}
297
298/*
299 * This turns all merge entries into "stage 3". That guarantees that
300 * when we read in the new tree (into "stage 1"), we won't lose sight
301 * of the fact that we had unmerged entries.
302 */
303static void mark_merge_entries(void)
304{
305 int i;
306 for (i = 0; i < active_nr; i++) {
307 struct cache_entry *ce = active_cache[i];
308 if (!ce_stage(ce))
309 continue;
310 ce->ce_flags |= htons(CE_STAGEMASK);
311 }
312}
313
5c21ac0e 314int run_diff_index(struct rev_info *revs, int cached)
e09ad6e1
JH
315{
316 int ret;
317 struct object *ent;
318 struct tree *tree;
319 const char *tree_name;
5c21ac0e
JH
320 int match_missing = 0;
321
322 /*
323 * Backward compatibility wart - "diff-index -m" does
324 * not mean "do not ignore merges", but totally different.
325 */
326 if (!revs->ignore_merges)
327 match_missing = 1;
e09ad6e1
JH
328
329 if (read_cache() < 0) {
330 perror("read_cache");
331 return -1;
332 }
333 mark_merge_entries();
334
1f1e895f
LT
335 ent = revs->pending.objects[0].item;
336 tree_name = revs->pending.objects[0].name;
e09ad6e1
JH
337 tree = parse_tree_indirect(ent->sha1);
338 if (!tree)
339 return error("bad tree object %s", tree_name);
340 if (read_tree(tree, 1, revs->prune_data))
341 return error("unable to read tree object %s", tree_name);
342 ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
343 cached, match_missing);
344 diffcore_std(&revs->diffopt);
345 diff_flush(&revs->diffopt);
346 return ret;
347}