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[git.git] / diff-index.c
1 #include "cache.h"
2 #include "diff.h"
3
4 static int cached_only = 0;
5 static int diff_output_format = DIFF_FORMAT_RAW;
6 static int diff_line_termination = '\n';
7 static int match_nonexisting = 0;
8 static int detect_rename = 0;
9 static int find_copies_harder = 0;
10 static int diff_setup_opt = 0;
11 static int diff_score_opt = 0;
12 static const char *pickaxe = NULL;
13 static int pickaxe_opts = 0;
14 static int diff_break_opt = -1;
15 static const char *orderfile = NULL;
16 static const char *diff_filter = NULL;
17
18 /* A file entry went away or appeared */
19 static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
20 {
21         diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
22 }
23
24 static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
25 {
26         unsigned char *sha1 = ce->sha1;
27         unsigned int mode = ce->ce_mode;
28
29         if (!cached_only) {
30                 static unsigned char no_sha1[20];
31                 int changed;
32                 struct stat st;
33                 if (lstat(ce->name, &st) < 0) {
34                         if (errno == ENOENT && match_nonexisting) {
35                                 *sha1p = sha1;
36                                 *modep = mode;
37                                 return 0;
38                         }
39                         return -1;
40                 }
41                 changed = ce_match_stat(ce, &st);
42                 if (changed) {
43                         mode = create_ce_mode(st.st_mode);
44                         sha1 = no_sha1;
45                 }
46         }
47
48         *sha1p = sha1;
49         *modep = mode;
50         return 0;
51 }
52
53 static void show_new_file(struct cache_entry *new)
54 {
55         unsigned char *sha1;
56         unsigned int mode;
57
58         /* New file in the index: it might actually be different in the working copy */
59         if (get_stat_data(new, &sha1, &mode) < 0)
60                 return;
61
62         show_file("+", new, sha1, mode);
63 }
64
65 static int show_modified(struct cache_entry *old,
66                          struct cache_entry *new,
67                          int report_missing)
68 {
69         unsigned int mode, oldmode;
70         unsigned char *sha1;
71
72         if (get_stat_data(new, &sha1, &mode) < 0) {
73                 if (report_missing)
74                         show_file("-", old, old->sha1, old->ce_mode);
75                 return -1;
76         }
77
78         oldmode = old->ce_mode;
79         if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
80             !find_copies_harder)
81                 return 0;
82
83         mode = ntohl(mode);
84         oldmode = ntohl(oldmode);
85
86         diff_change(oldmode, mode,
87                     old->sha1, sha1, old->name, NULL);
88         return 0;
89 }
90
91 static int diff_cache(struct cache_entry **ac, int entries, const char **pathspec)
92 {
93         while (entries) {
94                 struct cache_entry *ce = *ac;
95                 int same = (entries > 1) && ce_same_name(ce, ac[1]);
96
97                 if (!ce_path_match(ce, pathspec))
98                         goto skip_entry;
99
100                 switch (ce_stage(ce)) {
101                 case 0:
102                         /* No stage 1 entry? That means it's a new file */
103                         if (!same) {
104                                 show_new_file(ce);
105                                 break;
106                         }
107                         /* Show difference between old and new */
108                         show_modified(ac[1], ce, 1);
109                         break;
110                 case 1:
111                         /* No stage 3 (merge) entry? That means it's been deleted */
112                         if (!same) {
113                                 show_file("-", ce, ce->sha1, ce->ce_mode);
114                                 break;
115                         }
116                         /* We come here with ce pointing at stage 1
117                          * (original tree) and ac[1] pointing at stage
118                          * 3 (unmerged).  show-modified with
119                          * report-mising set to false does not say the
120                          * file is deleted but reports true if work
121                          * tree does not have it, in which case we
122                          * fall through to report the unmerged state.
123                          * Otherwise, we show the differences between
124                          * the original tree and the work tree.
125                          */
126                         if (!cached_only && !show_modified(ce, ac[1], 0))
127                                 break;
128                         /* fallthru */
129                 case 3:
130                         diff_unmerge(ce->name);
131                         break;
132
133                 default:
134                         die("impossible cache entry stage");
135                 }
136
137 skip_entry:
138                 /*
139                  * Ignore all the different stages for this file,
140                  * we've handled the relevant cases now.
141                  */
142                 do {
143                         ac++;
144                         entries--;
145                 } while (entries && ce_same_name(ce, ac[0]));
146         }
147         return 0;
148 }
149
150 /*
151  * This turns all merge entries into "stage 3". That guarantees that
152  * when we read in the new tree (into "stage 1"), we won't lose sight
153  * of the fact that we had unmerged entries.
154  */
155 static void mark_merge_entries(void)
156 {
157         int i;
158         for (i = 0; i < active_nr; i++) {
159                 struct cache_entry *ce = active_cache[i];
160                 if (!ce_stage(ce))
161                         continue;
162                 ce->ce_flags |= htons(CE_STAGEMASK);
163         }
164 }
165
166 static const char diff_cache_usage[] =
167 "git-diff-index [-m] [--cached] "
168 "[<common diff options>] <tree-ish> [<path>...]"
169 COMMON_DIFF_OPTIONS_HELP;
170
171 int main(int argc, char **argv)
172 {
173         const char *tree_name = NULL;
174         unsigned char sha1[20];
175         const char *prefix = setup_git_directory();
176         const char **pathspec = NULL;
177         void *tree;
178         unsigned long size;
179         int ret;
180         int allow_options = 1;
181         int i;
182
183         for (i = 1; i < argc; i++) {
184                 const char *arg = argv[i];
185
186                 if (!allow_options || *arg != '-') {
187                         if (tree_name)
188                                 break;
189                         tree_name = arg;
190                         continue;
191                 }
192                         
193                 if (!strcmp(arg, "--")) {
194                         allow_options = 0;
195                         continue;
196                 }
197                 if (!strcmp(arg, "-r")) {
198                         /* We accept the -r flag just to look like git-diff-tree */
199                         continue;
200                 }
201                 /* We accept the -u flag as a synonym for "-p" */
202                 if (!strcmp(arg, "-p") || !strcmp(arg, "-u")) {
203                         diff_output_format = DIFF_FORMAT_PATCH;
204                         continue;
205                 }
206                 if (!strncmp(arg, "-B", 2)) {
207                         if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
208                                 usage(diff_cache_usage);
209                         continue;
210                 }
211                 if (!strncmp(arg, "-M", 2)) {
212                         detect_rename = DIFF_DETECT_RENAME;
213                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
214                                 usage(diff_cache_usage);
215                         continue;
216                 }
217                 if (!strncmp(arg, "-C", 2)) {
218                         detect_rename = DIFF_DETECT_COPY;
219                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
220                                 usage(diff_cache_usage);
221                         continue;
222                 }
223                 if (!strcmp(arg, "--find-copies-harder")) {
224                         find_copies_harder = 1;
225                         continue;
226                 }
227                 if (!strcmp(arg, "-z")) {
228                         diff_line_termination = 0;
229                         continue;
230                 }
231                 if (!strcmp(arg, "--name-only")) {
232                         diff_output_format = DIFF_FORMAT_NAME;
233                         continue;
234                 }
235                 if (!strcmp(arg, "-R")) {
236                         diff_setup_opt |= DIFF_SETUP_REVERSE;
237                         continue;
238                 }
239                 if (!strncmp(arg, "-S", 2)) {
240                         pickaxe = arg + 2;
241                         continue;
242                 }
243                 if (!strncmp(arg, "--diff-filter=", 14)) {
244                         diff_filter = arg + 14;
245                         continue;
246                 }
247                 if (!strncmp(arg, "-O", 2)) {
248                         orderfile = arg + 2;
249                         continue;
250                 }
251                 if (!strcmp(arg, "--pickaxe-all")) {
252                         pickaxe_opts = DIFF_PICKAXE_ALL;
253                         continue;
254                 }
255                 if (!strcmp(arg, "-m")) {
256                         match_nonexisting = 1;
257                         continue;
258                 }
259                 if (!strcmp(arg, "--cached")) {
260                         cached_only = 1;
261                         continue;
262                 }
263                 usage(diff_cache_usage);
264         }
265
266         pathspec = get_pathspec(prefix, argv + i);
267
268         if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
269                 usage(diff_cache_usage);
270
271         if (!tree_name || get_sha1(tree_name, sha1))
272                 usage(diff_cache_usage);
273
274         read_cache();
275
276         /* The rest is for paths restriction. */
277         diff_setup(diff_setup_opt);
278
279         mark_merge_entries();
280
281         tree = read_object_with_reference(sha1, "tree", &size, NULL);
282         if (!tree)
283                 die("bad tree object %s", tree_name);
284         if (read_tree(tree, size, 1, pathspec))
285                 die("unable to read tree object %s", tree_name);
286
287         ret = diff_cache(active_cache, active_nr, pathspec);
288
289         diffcore_std(pathspec,
290                      detect_rename, diff_score_opt,
291                      pickaxe, pickaxe_opts,
292                      diff_break_opt,
293                      orderfile, diff_filter);
294         diff_flush(diff_output_format, diff_line_termination);
295         return ret;
296 }