Merge http://www.kernel.org/pub/scm/gitk/gitk
[git] / diff-tree.c
1 #include "cache.h"
2 #include "diff.h"
3 #include "commit.h"
4
5 static int show_root_diff = 0;
6 static int no_commit_id = 0;
7 static int verbose_header = 0;
8 static int ignore_merges = 1;
9 static int read_stdin = 0;
10
11 static const char *header = NULL;
12 static const char *header_prefix = "";
13 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
14
15 static struct diff_options diff_options;
16
17 static void call_diff_setup_done(void)
18 {
19         diff_setup_done(&diff_options);
20 }
21
22 static int call_diff_flush(void)
23 {
24         diffcore_std(&diff_options);
25         if (diff_queue_is_empty()) {
26                 int saved_fmt = diff_options.output_format;
27                 diff_options.output_format = DIFF_FORMAT_NO_OUTPUT;
28                 diff_flush(&diff_options);
29                 diff_options.output_format = saved_fmt;
30                 return 0;
31         }
32         if (header) {
33                 if (!no_commit_id)
34                         printf("%s%c", header, diff_options.line_termination);
35                 header = NULL;
36         }
37         diff_flush(&diff_options);
38         return 1;
39 }
40
41 static int diff_tree_sha1_top(const unsigned char *old,
42                               const unsigned char *new, const char *base)
43 {
44         int ret;
45
46         call_diff_setup_done();
47         ret = diff_tree_sha1(old, new, base, &diff_options);
48         call_diff_flush();
49         return ret;
50 }
51
52 static int diff_root_tree(const unsigned char *new, const char *base)
53 {
54         int retval;
55         void *tree;
56         struct tree_desc empty, real;
57
58         call_diff_setup_done();
59         tree = read_object_with_reference(new, "tree", &real.size, NULL);
60         if (!tree)
61                 die("unable to read root tree (%s)", sha1_to_hex(new));
62         real.buf = tree;
63
64         empty.buf = "";
65         empty.size = 0;
66         retval = diff_tree(&empty, &real, base, &diff_options);
67         free(tree);
68         call_diff_flush();
69         return retval;
70 }
71
72 static const char *generate_header(const char *commit, const char *parent, const char *msg)
73 {
74         static char this_header[16384];
75         int offset;
76         unsigned long len;
77
78         if (!verbose_header)
79                 return commit;
80
81         len = strlen(msg);
82         offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
83         offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
84         return this_header;
85 }
86
87 static int diff_tree_commit(const unsigned char *commit_sha1)
88 {
89         struct commit *commit;
90         struct commit_list *parents;
91         char name[50];
92         unsigned char sha1[20];
93
94         sprintf(name, "%s^0", sha1_to_hex(commit_sha1));
95         if (get_sha1(name, sha1))
96                 return -1;
97         name[40] = 0;
98         commit = lookup_commit(sha1);
99         
100         /* Root commit? */
101         if (show_root_diff && !commit->parents) {
102                 header = generate_header(name, "root", commit->buffer);
103                 diff_root_tree(commit_sha1, "");
104         }
105
106         /* More than one parent? */
107         if (ignore_merges && commit->parents && commit->parents->next)
108                         return 0;
109
110         for (parents = commit->parents; parents; parents = parents->next) {
111                 struct commit *parent = parents->item;
112                 header = generate_header(name,
113                                          sha1_to_hex(parent->object.sha1),
114                                          commit->buffer);
115                 diff_tree_sha1_top(parent->object.sha1, commit_sha1, "");
116                 if (!header && verbose_header) {
117                         header_prefix = "\ndiff-tree ";
118                         /*
119                          * Don't print multiple merge entries if we
120                          * don't print the diffs.
121                          */
122                 }
123         }
124         return 0;
125 }
126
127 static int diff_tree_stdin(char *line)
128 {
129         int len = strlen(line);
130         unsigned char commit[20], parent[20];
131         static char this_header[1000];
132
133         if (!len || line[len-1] != '\n')
134                 return -1;
135         line[len-1] = 0;
136         if (get_sha1_hex(line, commit))
137                 return -1;
138         if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
139                 line[40] = 0;
140                 line[81] = 0;
141                 sprintf(this_header, "%s (from %s)\n", line, line+41);
142                 header = this_header;
143                 return diff_tree_sha1_top(parent, commit, "");
144         }
145         line[40] = 0;
146         return diff_tree_commit(commit);
147 }
148
149 static const char diff_tree_usage[] =
150 "git-diff-tree [--stdin] [-m] [-s] [-v] [--pretty] [-t] [-r] [--root] "
151 "[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
152 "  -r            diff recursively\n"
153 "  --root        include the initial commit as diff against /dev/null\n"
154 COMMON_DIFF_OPTIONS_HELP;
155
156 int main(int argc, const char **argv)
157 {
158         int nr_sha1;
159         char line[1000];
160         unsigned char sha1[2][20];
161         const char *prefix = setup_git_directory();
162
163         git_config(git_diff_config);
164         nr_sha1 = 0;
165         diff_setup(&diff_options);
166
167         for (;;) {
168                 int diff_opt_cnt;
169                 const char *arg;
170
171                 argv++;
172                 argc--;
173                 arg = *argv;
174                 if (!arg)
175                         break;
176
177                 if (*arg != '-') {
178                         if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
179                                 nr_sha1++;
180                                 continue;
181                         }
182                         break;
183                 }
184
185                 diff_opt_cnt = diff_opt_parse(&diff_options, argv, argc);
186                 if (diff_opt_cnt < 0)
187                         usage(diff_tree_usage);
188                 else if (diff_opt_cnt) {
189                         argv += diff_opt_cnt - 1;
190                         argc -= diff_opt_cnt - 1;
191                         continue;
192                 }
193
194
195                 if (!strcmp(arg, "--")) {
196                         argv++;
197                         argc--;
198                         break;
199                 }
200                 if (!strcmp(arg, "-r")) {
201                         diff_options.recursive = 1;
202                         continue;
203                 }
204                 if (!strcmp(arg, "-t")) {
205                         diff_options.recursive = 1;
206                         diff_options.tree_in_recursive = 1;
207                         continue;
208                 }
209                 if (!strcmp(arg, "-m")) {
210                         ignore_merges = 0;
211                         continue;
212                 }
213                 if (!strcmp(arg, "-v")) {
214                         verbose_header = 1;
215                         header_prefix = "diff-tree ";
216                         continue;
217                 }
218                 if (!strncmp(arg, "--pretty", 8)) {
219                         verbose_header = 1;
220                         header_prefix = "diff-tree ";
221                         commit_format = get_commit_format(arg+8);
222                         continue;
223                 }
224                 if (!strcmp(arg, "--stdin")) {
225                         read_stdin = 1;
226                         continue;
227                 }
228                 if (!strcmp(arg, "--root")) {
229                         show_root_diff = 1;
230                         continue;
231                 }
232                 if (!strcmp(arg, "--no-commit-id")) {
233                         no_commit_id = 1;
234                         continue;
235                 }
236                 usage(diff_tree_usage);
237         }
238         if (diff_options.output_format == DIFF_FORMAT_PATCH)
239                 diff_options.recursive = 1;
240
241         diff_tree_setup_paths(get_pathspec(prefix, argv));
242
243         switch (nr_sha1) {
244         case 0:
245                 if (!read_stdin)
246                         usage(diff_tree_usage);
247                 break;
248         case 1:
249                 diff_tree_commit(sha1[0]);
250                 break;
251         case 2:
252                 diff_tree_sha1_top(sha1[0], sha1[1], "");
253                 break;
254         }
255
256         if (!read_stdin)
257                 return 0;
258
259         if (diff_options.detect_rename)
260                 diff_options.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
261                                        DIFF_SETUP_USE_CACHE);
262         while (fgets(line, sizeof(line), stdin))
263                 diff_tree_stdin(line);
264
265         return 0;
266 }