[PATCH] Diffcore updates.
[git/git.git] / diff-cache.c
1 #include "cache.h"
2 #include "diff.h"
3
4 static int cached_only = 0;
5 static int diff_output_format = DIFF_FORMAT_HUMAN;
6 static int match_nonexisting = 0;
7 static int detect_rename = 0;
8 static int reverse_diff = 0;
9 static int diff_score_opt = 0;
10 static const char *pickaxe = NULL;
11
12 /* A file entry went away or appeared */
13 static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
14 {
15 diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
16 }
17
18 static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
19 {
20 unsigned char *sha1 = ce->sha1;
21 unsigned int mode = ce->ce_mode;
22
23 if (!cached_only) {
24 static unsigned char no_sha1[20];
25 int changed;
26 struct stat st;
27 if (lstat(ce->name, &st) < 0) {
28 if (errno == ENOENT && match_nonexisting) {
29 *sha1p = sha1;
30 *modep = mode;
31 return 0;
32 }
33 return -1;
34 }
35 changed = ce_match_stat(ce, &st);
36 if (changed) {
37 mode = create_ce_mode(st.st_mode);
38 sha1 = no_sha1;
39 }
40 }
41
42 *sha1p = sha1;
43 *modep = mode;
44 return 0;
45 }
46
47 static void show_new_file(struct cache_entry *new)
48 {
49 unsigned char *sha1;
50 unsigned int mode;
51
52 /* New file in the index: it might actually be different in the working copy */
53 if (get_stat_data(new, &sha1, &mode) < 0)
54 return;
55
56 show_file("+", new, sha1, mode);
57 }
58
59 static int show_modified(struct cache_entry *old,
60 struct cache_entry *new,
61 int report_missing)
62 {
63 unsigned int mode, oldmode;
64 unsigned char *sha1;
65
66 if (get_stat_data(new, &sha1, &mode) < 0) {
67 if (report_missing)
68 show_file("-", old, old->sha1, old->ce_mode);
69 return -1;
70 }
71
72 oldmode = old->ce_mode;
73 if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
74 detect_rename < DIFF_DETECT_COPY)
75 return 0;
76
77 mode = ntohl(mode);
78 oldmode = ntohl(oldmode);
79
80 diff_change(oldmode, mode,
81 old->sha1, sha1, old->name, NULL);
82 return 0;
83 }
84
85 static int diff_cache(struct cache_entry **ac, int entries)
86 {
87 while (entries) {
88 struct cache_entry *ce = *ac;
89 int same = (entries > 1) && ce_same_name(ce, ac[1]);
90
91 switch (ce_stage(ce)) {
92 case 0:
93 /* No stage 1 entry? That means it's a new file */
94 if (!same) {
95 show_new_file(ce);
96 break;
97 }
98 /* Show difference between old and new */
99 show_modified(ac[1], ce, 1);
100 break;
101 case 1:
102 /* No stage 3 (merge) entry? That means it's been deleted */
103 if (!same) {
104 show_file("-", ce, ce->sha1, ce->ce_mode);
105 break;
106 }
107 /* We come here with ce pointing at stage 1
108 * (original tree) and ac[1] pointing at stage
109 * 3 (unmerged). show-modified with
110 * report-mising set to false does not say the
111 * file is deleted but reports true if work
112 * tree does not have it, in which case we
113 * fall through to report the unmerged state.
114 * Otherwise, we show the differences between
115 * the original tree and the work tree.
116 */
117 if (!cached_only && !show_modified(ce, ac[1], 0))
118 break;
119 /* fallthru */
120 case 3:
121 diff_unmerge(ce->name);
122 break;
123
124 default:
125 die("impossible cache entry stage");
126 }
127
128 /*
129 * Ignore all the different stages for this file,
130 * we've handled the relevant cases now.
131 */
132 do {
133 ac++;
134 entries--;
135 } while (entries && ce_same_name(ce, ac[0]));
136 }
137 return 0;
138 }
139
140 /*
141 * This turns all merge entries into "stage 3". That guarantees that
142 * when we read in the new tree (into "stage 1"), we won't lose sight
143 * of the fact that we had unmerged entries.
144 */
145 static void mark_merge_entries(void)
146 {
147 int i;
148 for (i = 0; i < active_nr; i++) {
149 struct cache_entry *ce = active_cache[i];
150 if (!ce_stage(ce))
151 continue;
152 ce->ce_flags |= htons(CE_STAGEMASK);
153 }
154 }
155
156 static char *diff_cache_usage =
157 "git-diff-cache [-p] [-r] [-z] [-m] [-M] [-C] [-R] [-S<string>] [--cached] <tree-ish>";
158
159 int main(int argc, const char **argv)
160 {
161 unsigned char tree_sha1[20];
162 void *tree;
163 unsigned long size;
164 int ret;
165
166 read_cache();
167 while (argc > 2) {
168 const char *arg = argv[1];
169 argv++;
170 argc--;
171 if (!strcmp(arg, "-r")) {
172 /* We accept the -r flag just to look like git-diff-tree */
173 continue;
174 }
175 if (!strcmp(arg, "-p")) {
176 diff_output_format = DIFF_FORMAT_PATCH;
177 continue;
178 }
179 if (!strncmp(arg, "-M", 2)) {
180 detect_rename = DIFF_DETECT_RENAME;
181 diff_score_opt = diff_scoreopt_parse(arg);
182 continue;
183 }
184 if (!strncmp(arg, "-C", 2)) {
185 detect_rename = DIFF_DETECT_COPY;
186 diff_score_opt = diff_scoreopt_parse(arg);
187 continue;
188 }
189 if (!strcmp(arg, "-z")) {
190 diff_output_format = DIFF_FORMAT_MACHINE;
191 continue;
192 }
193 if (!strcmp(arg, "-R")) {
194 reverse_diff = 1;
195 continue;
196 }
197 if (!strcmp(arg, "-S")) {
198 pickaxe = arg + 2;
199 continue;
200 }
201 if (!strcmp(arg, "-m")) {
202 match_nonexisting = 1;
203 continue;
204 }
205 if (!strcmp(arg, "--cached")) {
206 cached_only = 1;
207 continue;
208 }
209 usage(diff_cache_usage);
210 }
211
212 if (argc < 2 || get_sha1(argv[1], tree_sha1))
213 usage(diff_cache_usage);
214 argv++;
215 argc--;
216
217 /* The rest is for paths restriction. */
218
219 diff_setup(reverse_diff);
220
221 mark_merge_entries();
222
223 tree = read_object_with_reference(tree_sha1, "tree", &size, NULL);
224 if (!tree)
225 die("bad tree object %s", argv[1]);
226 if (read_tree(tree, size, 1))
227 die("unable to read tree object %s", argv[1]);
228
229 ret = diff_cache(active_cache, active_nr);
230 if (detect_rename)
231 diffcore_rename(detect_rename, diff_score_opt);
232 diffcore_prune();
233 if (pickaxe)
234 diffcore_pickaxe(pickaxe);
235 if (2 <= argc)
236 diffcore_pathspec(argv + 1);
237 diff_flush(diff_output_format);
238 return ret;
239 }