979f792b6758101cb490f36ba3acff5d7d4b4473
[git.git] / diff-tree.c
1 #include "cache.h"
2 #include "diff.h"
3 #include "commit.h"
4 #include "log-tree.h"
5
6 static struct rev_info log_tree_opt;
7
8 static int diff_tree_commit_sha1(const unsigned char *sha1)
9 {
10         struct commit *commit = lookup_commit_reference(sha1);
11         if (!commit)
12                 return -1;
13         return log_tree_commit(&log_tree_opt, commit);
14 }
15
16 static int diff_tree_stdin(char *line)
17 {
18         int len = strlen(line);
19         unsigned char sha1[20];
20         struct commit *commit;
21
22         if (!len || line[len-1] != '\n')
23                 return -1;
24         line[len-1] = 0;
25         if (get_sha1_hex(line, sha1))
26                 return -1;
27         commit = lookup_commit(sha1);
28         if (!commit || parse_commit(commit))
29                 return -1;
30         if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
31                 /* Graft the fake parents locally to the commit */
32                 int pos = 41;
33                 struct commit_list **pptr, *parents;
34
35                 /* Free the real parent list */
36                 for (parents = commit->parents; parents; ) {
37                         struct commit_list *tmp = parents->next;
38                         free(parents);
39                         parents = tmp;
40                 }
41                 commit->parents = NULL;
42                 pptr = &(commit->parents);
43                 while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
44                         struct commit *parent = lookup_commit(sha1);
45                         if (parent) {
46                                 pptr = &commit_list_insert(parent, pptr)->next;
47                         }
48                         pos += 41;
49                 }
50         }
51         return log_tree_commit(&log_tree_opt, commit);
52 }
53
54 static const char diff_tree_usage[] =
55 "git-diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
56 "[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
57 "  -r            diff recursively\n"
58 "  --root        include the initial commit as diff against /dev/null\n"
59 COMMON_DIFF_OPTIONS_HELP;
60
61 int main(int argc, const char **argv)
62 {
63         int nr_sha1;
64         char line[1000];
65         struct object *tree1, *tree2;
66         static struct rev_info *opt = &log_tree_opt;
67         struct object_list *list;
68         int read_stdin = 0;
69
70         git_config(git_diff_config);
71         nr_sha1 = 0;
72         opt->abbrev = 0;
73         argc = setup_revisions(argc, argv, opt, NULL);
74
75         while (--argc > 0) {
76                 const char *arg = *++argv;
77
78                 if (!strcmp(arg, "--stdin")) {
79                         read_stdin = 1;
80                         continue;
81                 }
82                 usage(diff_tree_usage);
83         }
84
85         /*
86          * NOTE! "setup_revisions()" will have inserted the revisions
87          * it parsed in reverse order. So if you do
88          *
89          *      git-diff-tree a b
90          *
91          * the commit list will be "b" -> "a" -> NULL, so we reverse
92          * the order of the objects if the first one is not marked
93          * UNINTERESTING.
94          */
95         nr_sha1 = 0;
96         list = opt->pending_objects;
97         if (list) {
98                 nr_sha1++;
99                 tree1 = list->item;
100                 list = list->next;
101                 if (list) {
102                         nr_sha1++;
103                         tree2 = tree1;
104                         tree1 = list->item;
105                         if (list->next)
106                                 usage(diff_tree_usage);
107                         /* Switch them around if the second one was uninteresting.. */
108                         if (tree2->flags & UNINTERESTING) {
109                                 struct object *tmp = tree2;
110                                 tree2 = tree1;
111                                 tree1 = tmp;
112                         }
113                 }
114         }
115
116         switch (nr_sha1) {
117         case 0:
118                 if (!read_stdin)
119                         usage(diff_tree_usage);
120                 break;
121         case 1:
122                 diff_tree_commit_sha1(tree1->sha1);
123                 break;
124         case 2:
125                 diff_tree_sha1(tree1->sha1,
126                                tree2->sha1,
127                                "", &opt->diffopt);
128                 log_tree_diff_flush(opt);
129                 break;
130         }
131
132         if (!read_stdin)
133                 return 0;
134
135         if (opt->diffopt.detect_rename)
136                 opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
137                                        DIFF_SETUP_USE_CACHE);
138         while (fgets(line, sizeof(line), stdin))
139                 diff_tree_stdin(line);
140
141         return 0;
142 }