entry.c: fix possible buffer overflow in remove_subtree()
[git/mjg.git] / builtin / diff-tree.c
blobbe6417d166abf428d379a70b9d67f894da4641d1
1 #include "cache.h"
2 #include "diff.h"
3 #include "commit.h"
4 #include "log-tree.h"
5 #include "builtin.h"
6 #include "submodule.h"
8 static struct rev_info log_tree_opt;
10 static int diff_tree_commit_sha1(const unsigned char *sha1)
12 struct commit *commit = lookup_commit_reference(sha1);
13 if (!commit)
14 return -1;
15 return log_tree_commit(&log_tree_opt, commit);
18 /* Diff one or more commits. */
19 static int stdin_diff_commit(struct commit *commit, char *line, int len)
21 unsigned char sha1[20];
22 if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
23 /* Graft the fake parents locally to the commit */
24 int pos = 41;
25 struct commit_list **pptr, *parents;
27 /* Free the real parent list */
28 for (parents = commit->parents; parents; ) {
29 struct commit_list *tmp = parents->next;
30 free(parents);
31 parents = tmp;
33 commit->parents = NULL;
34 pptr = &(commit->parents);
35 while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
36 struct commit *parent = lookup_commit(sha1);
37 if (parent) {
38 pptr = &commit_list_insert(parent, pptr)->next;
40 pos += 41;
43 return log_tree_commit(&log_tree_opt, commit);
46 /* Diff two trees. */
47 static int stdin_diff_trees(struct tree *tree1, char *line, int len)
49 unsigned char sha1[20];
50 struct tree *tree2;
51 if (len != 82 || !isspace(line[40]) || get_sha1_hex(line + 41, sha1))
52 return error("Need exactly two trees, separated by a space");
53 tree2 = lookup_tree(sha1);
54 if (!tree2 || parse_tree(tree2))
55 return -1;
56 printf("%s %s\n", sha1_to_hex(tree1->object.sha1),
57 sha1_to_hex(tree2->object.sha1));
58 diff_tree_sha1(tree1->object.sha1, tree2->object.sha1,
59 "", &log_tree_opt.diffopt);
60 log_tree_diff_flush(&log_tree_opt);
61 return 0;
64 static int diff_tree_stdin(char *line)
66 int len = strlen(line);
67 unsigned char sha1[20];
68 struct object *obj;
70 if (!len || line[len-1] != '\n')
71 return -1;
72 line[len-1] = 0;
73 if (get_sha1_hex(line, sha1))
74 return -1;
75 obj = lookup_unknown_object(sha1);
76 if (!obj || !obj->parsed)
77 obj = parse_object(sha1);
78 if (!obj)
79 return -1;
80 if (obj->type == OBJ_COMMIT)
81 return stdin_diff_commit((struct commit *)obj, line, len);
82 if (obj->type == OBJ_TREE)
83 return stdin_diff_trees((struct tree *)obj, line, len);
84 error("Object %s is a %s, not a commit or tree",
85 sha1_to_hex(sha1), typename(obj->type));
86 return -1;
89 static const char diff_tree_usage[] =
90 "git diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
91 "[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
92 " -r diff recursively\n"
93 " --root include the initial commit as diff against /dev/null\n"
94 COMMON_DIFF_OPTIONS_HELP;
96 static void diff_tree_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
98 if (!rev->diffopt.output_format) {
99 if (rev->dense_combined_merges)
100 rev->diffopt.output_format = DIFF_FORMAT_PATCH;
101 else
102 rev->diffopt.output_format = DIFF_FORMAT_RAW;
106 int cmd_diff_tree(int argc, const char **argv, const char *prefix)
108 int nr_sha1;
109 char line[1000];
110 struct object *tree1, *tree2;
111 static struct rev_info *opt = &log_tree_opt;
112 struct setup_revision_opt s_r_opt;
113 int read_stdin = 0;
115 init_revisions(opt, prefix);
116 gitmodules_config();
117 git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
118 opt->abbrev = 0;
119 opt->diff = 1;
120 opt->disable_stdin = 1;
121 memset(&s_r_opt, 0, sizeof(s_r_opt));
122 s_r_opt.tweak = diff_tree_tweak_rev;
123 argc = setup_revisions(argc, argv, opt, &s_r_opt);
125 while (--argc > 0) {
126 const char *arg = *++argv;
128 if (!strcmp(arg, "--stdin")) {
129 read_stdin = 1;
130 continue;
132 usage(diff_tree_usage);
136 * NOTE! We expect "a ^b" to be equal to "a..b", so we
137 * reverse the order of the objects if the second one
138 * is marked UNINTERESTING.
140 nr_sha1 = opt->pending.nr;
141 switch (nr_sha1) {
142 case 0:
143 if (!read_stdin)
144 usage(diff_tree_usage);
145 break;
146 case 1:
147 tree1 = opt->pending.objects[0].item;
148 diff_tree_commit_sha1(tree1->sha1);
149 break;
150 case 2:
151 tree1 = opt->pending.objects[0].item;
152 tree2 = opt->pending.objects[1].item;
153 if (tree2->flags & UNINTERESTING) {
154 struct object *tmp = tree2;
155 tree2 = tree1;
156 tree1 = tmp;
158 diff_tree_sha1(tree1->sha1,
159 tree2->sha1,
160 "", &opt->diffopt);
161 log_tree_diff_flush(opt);
162 break;
165 if (read_stdin) {
166 int saved_nrl = 0;
167 int saved_dcctc = 0;
169 if (opt->diffopt.detect_rename)
170 opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
171 DIFF_SETUP_USE_CACHE);
172 while (fgets(line, sizeof(line), stdin)) {
173 unsigned char sha1[20];
175 if (get_sha1_hex(line, sha1)) {
176 fputs(line, stdout);
177 fflush(stdout);
179 else {
180 diff_tree_stdin(line);
181 if (saved_nrl < opt->diffopt.needed_rename_limit)
182 saved_nrl = opt->diffopt.needed_rename_limit;
183 if (opt->diffopt.degraded_cc_to_c)
184 saved_dcctc = 1;
187 opt->diffopt.degraded_cc_to_c = saved_dcctc;
188 opt->diffopt.needed_rename_limit = saved_nrl;
191 return diff_result_code(&opt->diffopt, 0);