[PATCH] Deltification library work by Nicolas Pitre.
[git/git.git] / diff-cache.c
CommitLineData
e74f8f6a 1#include "cache.h"
f92a4465 2#include "diff.h"
e74f8f6a
LT
3
4static int cached_only = 0;
f92a4465 5static int generate_patch = 0;
160c8433 6static int match_nonexisting = 0;
e74f8f6a
LT
7static int line_termination = '\n';
8
e74f8f6a 9/* A file entry went away or appeared */
c9cddabe 10static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
e74f8f6a 11{
f92a4465 12 if (generate_patch)
c9cddabe 13 diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
f92a4465 14 else
c9cddabe
LT
15 printf("%s%06o\tblob\t%s\t%s%c", prefix, ntohl(mode),
16 sha1_to_hex(sha1), ce->name, line_termination);
e74f8f6a
LT
17}
18
c9cddabe 19static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
e74f8f6a 20{
c9cddabe
LT
21 unsigned char *sha1 = ce->sha1;
22 unsigned int mode = ce->ce_mode;
e74f8f6a
LT
23
24 if (!cached_only) {
25 static unsigned char no_sha1[20];
b5af9107 26 int changed;
e74f8f6a 27 struct stat st;
160c8433
LT
28 if (lstat(ce->name, &st) < 0) {
29 if (errno == ENOENT && match_nonexisting) {
30 *sha1p = sha1;
31 *modep = mode;
32 return 0;
33 }
e74f8f6a 34 return -1;
160c8433 35 }
5d728c84 36 changed = ce_match_stat(ce, &st);
e74f8f6a 37 if (changed) {
c9cddabe 38 mode = create_ce_mode(st.st_mode);
b5af9107 39 sha1 = no_sha1;
e74f8f6a
LT
40 }
41 }
42
c9cddabe
LT
43 *sha1p = sha1;
44 *modep = mode;
45 return 0;
46}
47
b836825b 48static void show_new_file(struct cache_entry *new)
c9cddabe
LT
49{
50 unsigned char *sha1;
51 unsigned int mode;
52
53 /* New file in the index: it might actually be different in the working copy */
54 if (get_stat_data(new, &sha1, &mode) < 0)
b836825b 55 return;
c9cddabe
LT
56
57 show_file("+", new, sha1, mode);
58}
59
66026590
JH
60static int show_modified(struct cache_entry *old,
61 struct cache_entry *new,
62 int report_missing)
c9cddabe
LT
63{
64 unsigned int mode, oldmode;
65 unsigned char *sha1;
bf0f910d 66 char old_sha1_hex[60];
c9cddabe
LT
67
68 if (get_stat_data(new, &sha1, &mode) < 0) {
66026590
JH
69 if (report_missing)
70 show_file("-", old, old->sha1, old->ce_mode);
c9cddabe
LT
71 return -1;
72 }
73
74 oldmode = old->ce_mode;
b5af9107 75 if (mode == oldmode && !memcmp(sha1, old->sha1, 20))
e74f8f6a
LT
76 return 0;
77
c9cddabe
LT
78 mode = ntohl(mode);
79 oldmode = ntohl(oldmode);
80
f92a4465
JH
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);
89 }
e74f8f6a
LT
90 return 0;
91}
92
b5af9107 93static int diff_cache(struct cache_entry **ac, int entries)
e74f8f6a 94{
b5af9107
LT
95 while (entries) {
96 struct cache_entry *ce = *ac;
dbbce55b 97 int same = (entries > 1) && ce_same_name(ce, ac[1]);
e74f8f6a 98
b0fe89ca
LT
99 switch (ce_stage(ce)) {
100 case 0:
101 /* No stage 1 entry? That means it's a new file */
102 if (!same) {
c9cddabe 103 show_new_file(ce);
b0fe89ca
LT
104 break;
105 }
106 /* Show difference between old and new */
66026590 107 show_modified(ac[1], ce, 1);
b0fe89ca
LT
108 break;
109 case 1:
110 /* No stage 3 (merge) entry? That means it's been deleted */
111 if (!same) {
c9cddabe 112 show_file("-", ce, ce->sha1, ce->ce_mode);
b0fe89ca
LT
113 break;
114 }
66026590
JH
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.
124 */
125 if (!cached_only && !show_modified(ce, ac[1], 0))
126 break;
127 /* fallthru */
b0fe89ca 128 case 3:
f92a4465
JH
129 if (generate_patch)
130 diff_unmerge(ce->name);
131 else
132 printf("U %s%c", ce->name, line_termination);
b0fe89ca
LT
133 break;
134
135 default:
136 die("impossible cache entry stage");
e74f8f6a 137 }
b0fe89ca
LT
138
139 /*
140 * Ignore all the different stages for this file,
141 * we've handled the relevant cases now.
142 */
143 do {
e74f8f6a
LT
144 ac++;
145 entries--;
dbbce55b 146 } while (entries && ce_same_name(ce, ac[0]));
e74f8f6a
LT
147 }
148 return 0;
149}
150
b0fe89ca
LT
151/*
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.
155 */
156static void mark_merge_entries(void)
b5af9107
LT
157{
158 int i;
159 for (i = 0; i < active_nr; i++) {
160 struct cache_entry *ce = active_cache[i];
161 if (!ce_stage(ce))
5697ecc7 162 continue;
b0fe89ca 163 ce->ce_flags |= htons(CE_STAGEMASK);
b5af9107
LT
164 }
165}
166
f92a4465 167static char *diff_cache_usage =
651df67b 168"git-diff-cache [-p] [-r] [-z] [-m] [--cached] <tree sha1>";
c5bac17a 169
e74f8f6a
LT
170int main(int argc, char **argv)
171{
172 unsigned char tree_sha1[20];
173 void *tree;
174 unsigned long size;
e74f8f6a
LT
175
176 read_cache();
177 while (argc > 2) {
178 char *arg = argv[1];
179 argv++;
180 argc--;
181 if (!strcmp(arg, "-r")) {
b5af9107 182 /* We accept the -r flag just to look like diff-tree */
e74f8f6a
LT
183 continue;
184 }
f92a4465
JH
185 if (!strcmp(arg, "-p")) {
186 generate_patch = 1;
187 continue;
188 }
e74f8f6a
LT
189 if (!strcmp(arg, "-z")) {
190 line_termination = '\0';
191 continue;
192 }
160c8433
LT
193 if (!strcmp(arg, "-m")) {
194 match_nonexisting = 1;
195 continue;
196 }
e74f8f6a
LT
197 if (!strcmp(arg, "--cached")) {
198 cached_only = 1;
199 continue;
200 }
c5bac17a 201 usage(diff_cache_usage);
e74f8f6a
LT
202 }
203
3c249c95 204 if (argc != 2 || get_sha1(argv[1], tree_sha1))
c5bac17a 205 usage(diff_cache_usage);
e74f8f6a 206
b0fe89ca 207 mark_merge_entries();
b5af9107 208
40469ee9 209 tree = read_object_with_reference(tree_sha1, "tree", &size, 0);
e74f8f6a
LT
210 if (!tree)
211 die("bad tree object %s", argv[1]);
b5af9107
LT
212 if (read_tree(tree, size, 1))
213 die("unable to read tree object %s", argv[1]);
e74f8f6a 214
b5af9107 215 return diff_cache(active_cache, active_nr);
e74f8f6a 216}