Document git-merge-cache -o
[git/repo.git] / diff-cache.c
blob84527190fef259dc8e8865693fe5591be86f79c4
1 #include "cache.h"
2 #include "diff.h"
4 static int cached_only = 0;
5 static int generate_patch = 0;
6 static int match_nonexisting = 0;
7 static int line_termination = '\n';
9 /* A file entry went away or appeared */
10 static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
12 if (generate_patch)
13 diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
14 else
15 printf("%s%06o\tblob\t%s\t%s%c", prefix, ntohl(mode),
16 sha1_to_hex(sha1), ce->name, line_termination);
19 static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
21 unsigned char *sha1 = ce->sha1;
22 unsigned int mode = ce->ce_mode;
24 if (!cached_only) {
25 static unsigned char no_sha1[20];
26 int changed;
27 struct stat st;
28 if (lstat(ce->name, &st) < 0) {
29 if (errno == ENOENT && match_nonexisting) {
30 *sha1p = sha1;
31 *modep = mode;
32 return 0;
34 return -1;
36 changed = cache_match_stat(ce, &st);
37 if (changed) {
38 mode = create_ce_mode(st.st_mode);
39 sha1 = no_sha1;
43 *sha1p = sha1;
44 *modep = mode;
45 return 0;
48 static void show_new_file(struct cache_entry *new)
50 unsigned char *sha1;
51 unsigned int mode;
53 /* New file in the index: it might actually be different in the working copy */
54 if (get_stat_data(new, &sha1, &mode) < 0)
55 return;
57 show_file("+", new, sha1, mode);
60 static int show_modified(struct cache_entry *old,
61 struct cache_entry *new,
62 int report_missing)
64 unsigned int mode, oldmode;
65 unsigned char *sha1;
66 unsigned char old_sha1_hex[60];
68 if (get_stat_data(new, &sha1, &mode) < 0) {
69 if (report_missing)
70 show_file("-", old, old->sha1, old->ce_mode);
71 return -1;
74 oldmode = old->ce_mode;
75 if (mode == oldmode && !memcmp(sha1, old->sha1, 20))
76 return 0;
78 mode = ntohl(mode);
79 oldmode = ntohl(oldmode);
81 if (generate_patch)
82 diff_change(oldmode, mode,
83 old->sha1, sha1, old->name, NULL);
84 else {
85 strcpy(old_sha1_hex, sha1_to_hex(old->sha1));
86 printf("*%06o->%06o\tblob\t%s->%s\t%s%c", oldmode, mode,
87 old_sha1_hex, sha1_to_hex(sha1),
88 old->name, line_termination);
90 return 0;
93 static int diff_cache(struct cache_entry **ac, int entries)
95 while (entries) {
96 struct cache_entry *ce = *ac;
97 int same = (entries > 1) && same_name(ce, ac[1]);
99 switch (ce_stage(ce)) {
100 case 0:
101 /* No stage 1 entry? That means it's a new file */
102 if (!same) {
103 show_new_file(ce);
104 break;
106 /* Show difference between old and new */
107 show_modified(ac[1], ce, 1);
108 break;
109 case 1:
110 /* No stage 3 (merge) entry? That means it's been deleted */
111 if (!same) {
112 show_file("-", ce, ce->sha1, ce->ce_mode);
113 break;
115 /* We come here with ce pointing at stage 1
116 * (original tree) and ac[1] pointing at stage
117 * 3 (unmerged). show-modified with
118 * report-mising set to false does not say the
119 * file is deleted but reports true if work
120 * tree does not have it, in which case we
121 * fall through to report the unmerged state.
122 * Otherwise, we show the differences between
123 * the original tree and the work tree.
125 if (!cached_only && !show_modified(ce, ac[1], 0))
126 break;
127 /* fallthru */
128 case 3:
129 if (generate_patch)
130 diff_unmerge(ce->name);
131 else
132 printf("U %s%c", ce->name, line_termination);
133 break;
135 default:
136 die("impossible cache entry stage");
140 * Ignore all the different stages for this file,
141 * we've handled the relevant cases now.
143 do {
144 ac++;
145 entries--;
146 } while (entries && same_name(ce, ac[0]));
148 return 0;
152 * This turns all merge entries into "stage 3". That guarantees that
153 * when we read in the new tree (into "stage 1"), we won't lose sight
154 * of the fact that we had unmerged entries.
156 static void mark_merge_entries(void)
158 int i;
159 for (i = 0; i < active_nr; i++) {
160 struct cache_entry *ce = active_cache[i];
161 if (!ce_stage(ce))
162 continue;
163 ce->ce_flags |= htons(CE_STAGEMASK);
167 static char *diff_cache_usage =
168 "git-diff-cache [-p] [-r] [-z] [-m] [--cached] <tree sha1>";
170 int main(int argc, char **argv)
172 unsigned char tree_sha1[20];
173 void *tree;
174 unsigned long size;
176 read_cache();
177 while (argc > 2) {
178 char *arg = argv[1];
179 argv++;
180 argc--;
181 if (!strcmp(arg, "-r")) {
182 /* We accept the -r flag just to look like diff-tree */
183 continue;
185 if (!strcmp(arg, "-p")) {
186 generate_patch = 1;
187 continue;
189 if (!strcmp(arg, "-z")) {
190 line_termination = '\0';
191 continue;
193 if (!strcmp(arg, "-m")) {
194 match_nonexisting = 1;
195 continue;
197 if (!strcmp(arg, "--cached")) {
198 cached_only = 1;
199 continue;
201 usage(diff_cache_usage);
204 if (argc != 2 || get_sha1(argv[1], tree_sha1))
205 usage(diff_cache_usage);
207 mark_merge_entries();
209 tree = read_object_with_reference(tree_sha1, "tree", &size, 0);
210 if (!tree)
211 die("bad tree object %s", argv[1]);
212 if (read_tree(tree, size, 1))
213 die("unable to read tree object %s", argv[1]);
215 return diff_cache(active_cache, active_nr);