[PATCH] Diff overhaul, adding the other half of copy detection.
[git.git] / diff-files.c
1 /*
2  * GIT - The information manager from hell
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  */
6 #include "cache.h"
7 #include "diff.h"
8
9 static const char *diff_files_usage =
10 "git-diff-files [-p] [-q] [-r] [-z] [-M] [-C] [-R] [-S<string>] [paths...]";
11
12 static int generate_patch = 0;
13 static int line_termination = '\n';
14 static int detect_rename = 0;
15 static int reverse_diff = 0;
16 static int diff_score_opt = 0;
17 static char *pickaxe = 0;
18 static int silent = 0;
19
20 static int matches_pathspec(struct cache_entry *ce, char **spec, int cnt)
21 {
22         int i;
23         int namelen = ce_namelen(ce);
24         for (i = 0; i < cnt; i++) {
25                 int speclen = strlen(spec[i]);
26                 if (! strncmp(spec[i], ce->name, speclen) &&
27                     speclen <= namelen &&
28                     (ce->name[speclen] == 0 ||
29                      ce->name[speclen] == '/'))
30                         return 1;
31         }
32         return 0;
33 }
34
35 static void show_unmerge(const char *path)
36 {
37         diff_unmerge(path);
38 }
39
40 static void show_file(int pfx, struct cache_entry *ce)
41 {
42         diff_addremove(pfx, ntohl(ce->ce_mode), ce->sha1, ce->name, NULL);
43 }
44
45 static void show_modified(int oldmode, int mode,
46                           const unsigned char *old_sha1, const unsigned char *sha1,
47                           char *path)
48 {
49         diff_change(oldmode, mode, old_sha1, sha1, path, NULL);
50 }
51
52 int main(int argc, char **argv)
53 {
54         static const unsigned char null_sha1[20] = { 0, };
55         int entries = read_cache();
56         int i;
57
58         while (1 < argc && argv[1][0] == '-') {
59                 if (!strcmp(argv[1], "-p"))
60                         generate_patch = 1;
61                 else if (!strcmp(argv[1], "-q"))
62                         silent = 1;
63                 else if (!strcmp(argv[1], "-r"))
64                         ; /* no-op */
65                 else if (!strcmp(argv[1], "-s"))
66                         ; /* no-op */
67                 else if (!strcmp(argv[1], "-z"))
68                         line_termination = 0;
69                 else if (!strcmp(argv[1], "-R"))
70                         reverse_diff = 1;
71                 else if (!strcmp(argv[1], "-S"))
72                         pickaxe = argv[1] + 2;
73                 else if (!strncmp(argv[1], "-M", 2)) {
74                         diff_score_opt = diff_scoreopt_parse(argv[1]);
75                         detect_rename = generate_patch = 1;
76                 }
77                 else if (!strncmp(argv[1], "-C", 2)) {
78                         diff_score_opt = diff_scoreopt_parse(argv[1]);
79                         detect_rename = 2;
80                         generate_patch = 1;
81                 }
82                 else
83                         usage(diff_files_usage);
84                 argv++; argc--;
85         }
86
87         /* At this point, if argc == 1, then we are doing everything.
88          * Otherwise argv[1] .. argv[argc-1] have the explicit paths.
89          */
90         if (entries < 0) {
91                 perror("read_cache");
92                 exit(1);
93         }
94
95         diff_setup(detect_rename, diff_score_opt, pickaxe,
96                    reverse_diff, (generate_patch ? -1 : line_termination),
97                    NULL, 0);
98
99         for (i = 0; i < entries; i++) {
100                 struct stat st;
101                 unsigned int oldmode, mode;
102                 struct cache_entry *ce = active_cache[i];
103                 int changed;
104
105                 if (1 < argc &&
106                     ! matches_pathspec(ce, argv+1, argc-1))
107                         continue;
108
109                 if (ce_stage(ce)) {
110                         show_unmerge(ce->name);
111                         while (i < entries &&
112                                !strcmp(ce->name, active_cache[i]->name))
113                                 i++;
114                         i--; /* compensate for loop control increments */
115                         continue;
116                 }
117
118                 if (lstat(ce->name, &st) < 0) {
119                         if (errno != ENOENT && errno != ENOTDIR) {
120                                 perror(ce->name);
121                                 continue;
122                         }
123                         if (silent)
124                                 continue;
125                         show_file('-', ce);
126                         continue;
127                 }
128                 changed = ce_match_stat(ce, &st);
129                 if (!changed && detect_rename < 2)
130                         continue;
131
132                 oldmode = ntohl(ce->ce_mode);
133                 mode = (S_ISLNK(st.st_mode) ? S_IFLNK :
134                         S_IFREG | ce_permissions(st.st_mode));
135
136                 show_modified(oldmode, mode, ce->sha1, null_sha1,
137                               ce->name);
138         }
139         diff_flush();
140         return 0;
141 }