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