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[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 [-q] [-0/-1/2/3 |-c|--cc] [<common diff options>] [<path>...]"
11 COMMON_DIFF_OPTIONS_HELP;
12
13 static struct diff_options diff_options;
14 static int silent = 0;
15 static int diff_unmerged_stage = 2;
16 static int combine_merges = 0;
17 static int dense_combined_merges = 0;
18
19 static void show_unmerge(const char *path)
20 {
21         diff_unmerge(&diff_options, path);
22 }
23
24 static void show_file(int pfx, struct cache_entry *ce)
25 {
26         diff_addremove(&diff_options, pfx, ntohl(ce->ce_mode),
27                        ce->sha1, ce->name, NULL);
28 }
29
30 static void show_modified(int oldmode, int mode,
31                           const unsigned char *old_sha1, const unsigned char *sha1,
32                           char *path)
33 {
34         diff_change(&diff_options, oldmode, mode, old_sha1, sha1, path, NULL);
35 }
36
37 int main(int argc, const char **argv)
38 {
39         const char **pathspec;
40         const char *prefix = setup_git_directory();
41         int entries, i;
42
43         git_config(git_diff_config);
44         diff_setup(&diff_options);
45         while (1 < argc && argv[1][0] == '-') {
46                 if (!strcmp(argv[1], "--")) {
47                         argv++;
48                         argc--;
49                         break;
50                 }
51                 if (!strcmp(argv[1], "-0"))
52                         diff_unmerged_stage = 0;
53                 else if (!strcmp(argv[1], "-1"))
54                         diff_unmerged_stage = 1;
55                 else if (!strcmp(argv[1], "-2"))
56                         diff_unmerged_stage = 2;
57                 else if (!strcmp(argv[1], "-3"))
58                         diff_unmerged_stage = 3;
59                 else if (!strcmp(argv[1], "--base"))
60                         diff_unmerged_stage = 1;
61                 else if (!strcmp(argv[1], "--ours"))
62                         diff_unmerged_stage = 2;
63                 else if (!strcmp(argv[1], "--theirs"))
64                         diff_unmerged_stage = 3;
65                 else if (!strcmp(argv[1], "-q"))
66                         silent = 1;
67                 else if (!strcmp(argv[1], "-r"))
68                         ; /* no-op */
69                 else if (!strcmp(argv[1], "-s"))
70                         ; /* no-op */
71                 else if (!strcmp(argv[1], "-c"))
72                         combine_merges = 1;
73                 else if (!strcmp(argv[1], "--cc"))
74                         dense_combined_merges = combine_merges = 1;
75                 else {
76                         int diff_opt_cnt;
77                         diff_opt_cnt = diff_opt_parse(&diff_options,
78                                                       argv+1, argc-1);
79                         if (diff_opt_cnt < 0)
80                                 usage(diff_files_usage);
81                         else if (diff_opt_cnt) {
82                                 argv += diff_opt_cnt;
83                                 argc -= diff_opt_cnt;
84                                 continue;
85                         }
86                         else
87                                 usage(diff_files_usage);
88                 }
89                 argv++; argc--;
90         }
91         if (combine_merges) {
92                 diff_options.output_format = DIFF_FORMAT_PATCH;
93         }
94
95         /* Find the directory, and set up the pathspec */
96         pathspec = get_pathspec(prefix, argv + 1);
97         entries = read_cache();
98
99         if (diff_setup_done(&diff_options) < 0)
100                 usage(diff_files_usage);
101
102         /* At this point, if argc == 1, then we are doing everything.
103          * Otherwise argv[1] .. argv[argc-1] have the explicit paths.
104          */
105         if (entries < 0) {
106                 perror("read_cache");
107                 exit(1);
108         }
109
110         for (i = 0; i < entries; i++) {
111                 struct stat st;
112                 unsigned int oldmode, newmode;
113                 struct cache_entry *ce = active_cache[i];
114                 int changed;
115
116                 if (!ce_path_match(ce, pathspec))
117                         continue;
118
119                 if (ce_stage(ce)) {
120                         struct {
121                                 struct combine_diff_path p;
122                                 struct combine_diff_parent filler[5];
123                         } combine;
124                         int num_compare_stages = 0;
125
126                         combine.p.next = NULL;
127                         combine.p.len = ce_namelen(ce);
128                         combine.p.path = xmalloc(combine.p.len + 1);
129                         memcpy(combine.p.path, ce->name, combine.p.len);
130                         combine.p.path[combine.p.len] = 0;
131                         combine.p.mode = 0;
132                         memset(combine.p.sha1, 0, 20);
133                         memset(&combine.p.parent[0], 0,
134                                sizeof(combine.filler));
135
136                         while (i < entries) {
137                                 struct cache_entry *nce = active_cache[i];
138                                 int stage;
139
140                                 if (strcmp(ce->name, nce->name))
141                                         break;
142
143                                 /* Stage #2 (ours) is the first parent,
144                                  * stage #3 (theirs) is the second.
145                                  */
146                                 stage = ce_stage(nce);
147                                 if (2 <= stage) {
148                                         int mode = ntohl(nce->ce_mode);
149                                         num_compare_stages++;
150                                         memcpy(combine.p.parent[stage-2].sha1,
151                                                nce->sha1, 20);
152                                         combine.p.parent[stage-2].mode =
153                                                 DIFF_FILE_CANON_MODE(mode);
154                                 }
155
156                                 /* diff against the proper unmerged stage */
157                                 if (stage == diff_unmerged_stage)
158                                         ce = nce;
159                                 i++;
160                         }
161                         /*
162                          * Compensate for loop update
163                          */
164                         i--;
165
166                         if (combine_merges && num_compare_stages == 2) {
167                                 show_combined_diff(&combine.p, 2,
168                                                    dense_combined_merges,
169                                                    NULL);
170                                 free(combine.p.path);
171                                 continue;
172                         }
173                         free(combine.p.path);
174
175                         /*
176                          * Show the diff for the 'ce' if we found the one
177                          * from the desired stage.
178                          */
179                         show_unmerge(ce->name);
180                         if (ce_stage(ce) != diff_unmerged_stage)
181                                 continue;
182                 }
183
184                 if (lstat(ce->name, &st) < 0) {
185                         if (errno != ENOENT && errno != ENOTDIR) {
186                                 perror(ce->name);
187                                 continue;
188                         }
189                         if (silent)
190                                 continue;
191                         show_file('-', ce);
192                         continue;
193                 }
194                 changed = ce_match_stat(ce, &st);
195                 if (!changed && !diff_options.find_copies_harder)
196                         continue;
197                 oldmode = ntohl(ce->ce_mode);
198
199                 newmode = DIFF_FILE_CANON_MODE(st.st_mode);
200                 if (!trust_executable_bit &&
201                     S_ISREG(newmode) && S_ISREG(oldmode) &&
202                     ((newmode ^ oldmode) == 0111))
203                         newmode = oldmode;
204                 show_modified(oldmode, newmode,
205                               ce->sha1, (changed ? null_sha1 : ce->sha1),
206                               ce->name);
207         }
208         diffcore_std(&diff_options);
209         diff_flush(&diff_options);
210         return 0;
211 }