Add using merge subtree How-To
[git/fastimport.git] / builtin-diff-tree.c
blob832797ff3bb45751758f0d629abb2cf8fa4507ad
1 #include "cache.h"
2 #include "diff.h"
3 #include "commit.h"
4 #include "log-tree.h"
5 #include "builtin.h"
7 static struct rev_info log_tree_opt;
9 static int diff_tree_commit_sha1(const unsigned char *sha1)
11 struct commit *commit = lookup_commit_reference(sha1);
12 if (!commit)
13 return -1;
14 return log_tree_commit(&log_tree_opt, commit);
17 static int diff_tree_stdin(char *line)
19 int len = strlen(line);
20 unsigned char sha1[20];
21 struct commit *commit;
23 if (!len || line[len-1] != '\n')
24 return -1;
25 line[len-1] = 0;
26 if (get_sha1_hex(line, sha1))
27 return -1;
28 commit = lookup_commit(sha1);
29 if (!commit || parse_commit(commit))
30 return -1;
31 if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
32 /* Graft the fake parents locally to the commit */
33 int pos = 41;
34 struct commit_list **pptr, *parents;
36 /* Free the real parent list */
37 for (parents = commit->parents; parents; ) {
38 struct commit_list *tmp = parents->next;
39 free(parents);
40 parents = tmp;
42 commit->parents = NULL;
43 pptr = &(commit->parents);
44 while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
45 struct commit *parent = lookup_commit(sha1);
46 if (parent) {
47 pptr = &commit_list_insert(parent, pptr)->next;
49 pos += 41;
52 return log_tree_commit(&log_tree_opt, commit);
55 static const char diff_tree_usage[] =
56 "git-diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
57 "[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
58 " -r diff recursively\n"
59 " --root include the initial commit as diff against /dev/null\n"
60 COMMON_DIFF_OPTIONS_HELP;
62 int cmd_diff_tree(int argc, const char **argv, const char *prefix)
64 int nr_sha1;
65 char line[1000];
66 struct object *tree1, *tree2;
67 static struct rev_info *opt = &log_tree_opt;
68 int read_stdin = 0;
70 init_revisions(opt, prefix);
71 git_config(git_diff_basic_config); /* no "diff" UI options */
72 nr_sha1 = 0;
73 opt->abbrev = 0;
74 opt->diff = 1;
75 argc = setup_revisions(argc, argv, opt, NULL);
77 while (--argc > 0) {
78 const char *arg = *++argv;
80 if (!strcmp(arg, "--stdin")) {
81 read_stdin = 1;
82 continue;
84 usage(diff_tree_usage);
87 if (!opt->diffopt.output_format)
88 opt->diffopt.output_format = DIFF_FORMAT_RAW;
91 * NOTE! We expect "a ^b" to be equal to "a..b", so we
92 * reverse the order of the objects if the second one
93 * is marked UNINTERESTING.
95 nr_sha1 = opt->pending.nr;
96 switch (nr_sha1) {
97 case 0:
98 if (!read_stdin)
99 usage(diff_tree_usage);
100 break;
101 case 1:
102 tree1 = opt->pending.objects[0].item;
103 diff_tree_commit_sha1(tree1->sha1);
104 break;
105 case 2:
106 tree1 = opt->pending.objects[0].item;
107 tree2 = opt->pending.objects[1].item;
108 if (tree2->flags & UNINTERESTING) {
109 struct object *tmp = tree2;
110 tree2 = tree1;
111 tree1 = tmp;
113 diff_tree_sha1(tree1->sha1,
114 tree2->sha1,
115 "", &opt->diffopt);
116 log_tree_diff_flush(opt);
117 break;
120 if (read_stdin) {
121 if (opt->diffopt.detect_rename)
122 opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
123 DIFF_SETUP_USE_CACHE);
124 while (fgets(line, sizeof(line), stdin)) {
125 unsigned char sha1[20];
127 if (get_sha1_hex(line, sha1)) {
128 fputs(line, stdout);
129 fflush(stdout);
131 else
132 diff_tree_stdin(line);
136 return diff_result_code(&opt->diffopt, 0);