git-whatchanged: allow other pagers
[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 7static int line_termination = '\n';
5c97558c 8static int detect_rename = 0;
57fe64a4
JH
9static int reverse_diff = 0;
10static int diff_score_opt = 0;
e74f8f6a 11
e74f8f6a 12/* A file entry went away or appeared */
c9cddabe 13static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
e74f8f6a 14{
57fe64a4 15 diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
e74f8f6a
LT
16}
17
c9cddabe 18static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
e74f8f6a 19{
c9cddabe
LT
20 unsigned char *sha1 = ce->sha1;
21 unsigned int mode = ce->ce_mode;
e74f8f6a
LT
22
23 if (!cached_only) {
24 static unsigned char no_sha1[20];
b5af9107 25 int changed;
e74f8f6a 26 struct stat st;
160c8433
LT
27 if (lstat(ce->name, &st) < 0) {
28 if (errno == ENOENT && match_nonexisting) {
29 *sha1p = sha1;
30 *modep = mode;
31 return 0;
32 }
e74f8f6a 33 return -1;
160c8433 34 }
5d728c84 35 changed = ce_match_stat(ce, &st);
e74f8f6a 36 if (changed) {
c9cddabe 37 mode = create_ce_mode(st.st_mode);
b5af9107 38 sha1 = no_sha1;
e74f8f6a
LT
39 }
40 }
41
c9cddabe
LT
42 *sha1p = sha1;
43 *modep = mode;
44 return 0;
45}
46
b836825b 47static void show_new_file(struct cache_entry *new)
c9cddabe
LT
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)
b836825b 54 return;
c9cddabe
LT
55
56 show_file("+", new, sha1, mode);
57}
58
66026590
JH
59static int show_modified(struct cache_entry *old,
60 struct cache_entry *new,
61 int report_missing)
c9cddabe
LT
62{
63 unsigned int mode, oldmode;
64 unsigned char *sha1;
c9cddabe
LT
65
66 if (get_stat_data(new, &sha1, &mode) < 0) {
66026590
JH
67 if (report_missing)
68 show_file("-", old, old->sha1, old->ce_mode);
c9cddabe
LT
69 return -1;
70 }
71
72 oldmode = old->ce_mode;
b5af9107 73 if (mode == oldmode && !memcmp(sha1, old->sha1, 20))
e74f8f6a
LT
74 return 0;
75
c9cddabe
LT
76 mode = ntohl(mode);
77 oldmode = ntohl(oldmode);
78
57fe64a4
JH
79 diff_change(oldmode, mode,
80 old->sha1, sha1, old->name, NULL);
e74f8f6a
LT
81 return 0;
82}
83
b5af9107 84static int diff_cache(struct cache_entry **ac, int entries)
e74f8f6a 85{
b5af9107
LT
86 while (entries) {
87 struct cache_entry *ce = *ac;
dbbce55b 88 int same = (entries > 1) && ce_same_name(ce, ac[1]);
e74f8f6a 89
b0fe89ca
LT
90 switch (ce_stage(ce)) {
91 case 0:
92 /* No stage 1 entry? That means it's a new file */
93 if (!same) {
c9cddabe 94 show_new_file(ce);
b0fe89ca
LT
95 break;
96 }
97 /* Show difference between old and new */
66026590 98 show_modified(ac[1], ce, 1);
b0fe89ca
LT
99 break;
100 case 1:
101 /* No stage 3 (merge) entry? That means it's been deleted */
102 if (!same) {
c9cddabe 103 show_file("-", ce, ce->sha1, ce->ce_mode);
b0fe89ca
LT
104 break;
105 }
66026590
JH
106 /* We come here with ce pointing at stage 1
107 * (original tree) and ac[1] pointing at stage
108 * 3 (unmerged). show-modified with
109 * report-mising set to false does not say the
110 * file is deleted but reports true if work
111 * tree does not have it, in which case we
112 * fall through to report the unmerged state.
113 * Otherwise, we show the differences between
114 * the original tree and the work tree.
115 */
116 if (!cached_only && !show_modified(ce, ac[1], 0))
117 break;
118 /* fallthru */
b0fe89ca 119 case 3:
57fe64a4 120 diff_unmerge(ce->name);
b0fe89ca
LT
121 break;
122
123 default:
124 die("impossible cache entry stage");
e74f8f6a 125 }
b0fe89ca
LT
126
127 /*
128 * Ignore all the different stages for this file,
129 * we've handled the relevant cases now.
130 */
131 do {
e74f8f6a
LT
132 ac++;
133 entries--;
dbbce55b 134 } while (entries && ce_same_name(ce, ac[0]));
e74f8f6a
LT
135 }
136 return 0;
137}
138
b0fe89ca
LT
139/*
140 * This turns all merge entries into "stage 3". That guarantees that
141 * when we read in the new tree (into "stage 1"), we won't lose sight
142 * of the fact that we had unmerged entries.
143 */
144static void mark_merge_entries(void)
b5af9107
LT
145{
146 int i;
147 for (i = 0; i < active_nr; i++) {
148 struct cache_entry *ce = active_cache[i];
149 if (!ce_stage(ce))
5697ecc7 150 continue;
b0fe89ca 151 ce->ce_flags |= htons(CE_STAGEMASK);
b5af9107
LT
152 }
153}
154
f92a4465 155static char *diff_cache_usage =
57fe64a4 156"git-diff-cache [-p] [-r] [-z] [-m] [-M] [-R] [--cached] <tree-ish>";
c5bac17a 157
e74f8f6a
LT
158int main(int argc, char **argv)
159{
160 unsigned char tree_sha1[20];
161 void *tree;
162 unsigned long size;
5c97558c 163 int ret;
e74f8f6a
LT
164
165 read_cache();
166 while (argc > 2) {
167 char *arg = argv[1];
168 argv++;
169 argc--;
170 if (!strcmp(arg, "-r")) {
667bb59b 171 /* We accept the -r flag just to look like git-diff-tree */
e74f8f6a
LT
172 continue;
173 }
f92a4465
JH
174 if (!strcmp(arg, "-p")) {
175 generate_patch = 1;
176 continue;
177 }
57fe64a4 178 if (!strncmp(arg, "-M", 2)) {
5c97558c 179 generate_patch = detect_rename = 1;
57fe64a4 180 diff_score_opt = diff_scoreopt_parse(arg);
5c97558c
JH
181 continue;
182 }
e74f8f6a
LT
183 if (!strcmp(arg, "-z")) {
184 line_termination = '\0';
185 continue;
186 }
57fe64a4
JH
187 if (!strcmp(arg, "-R")) {
188 reverse_diff = 1;
189 continue;
190 }
160c8433
LT
191 if (!strcmp(arg, "-m")) {
192 match_nonexisting = 1;
193 continue;
194 }
e74f8f6a
LT
195 if (!strcmp(arg, "--cached")) {
196 cached_only = 1;
197 continue;
198 }
c5bac17a 199 usage(diff_cache_usage);
e74f8f6a
LT
200 }
201
3c249c95 202 if (argc != 2 || get_sha1(argv[1], tree_sha1))
c5bac17a 203 usage(diff_cache_usage);
e74f8f6a 204
57fe64a4
JH
205 diff_setup(detect_rename, diff_score_opt, reverse_diff,
206 (generate_patch ? -1 : line_termination),
e99d59ff 207 NULL, 0);
5c97558c 208
b0fe89ca 209 mark_merge_entries();
b5af9107 210
e99d59ff 211 tree = read_object_with_reference(tree_sha1, "tree", &size, NULL);
e74f8f6a
LT
212 if (!tree)
213 die("bad tree object %s", argv[1]);
b5af9107
LT
214 if (read_tree(tree, size, 1))
215 die("unable to read tree object %s", argv[1]);
e74f8f6a 216
5c97558c 217 ret = diff_cache(active_cache, active_nr);
57fe64a4 218 diff_flush();
5c97558c 219 return ret;
e74f8f6a 220}