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