Merge branch 'aw/contrib-subtree-doc-asciidoctor' into maint
[git] / builtin / diff-tree.c
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"
7
8 static struct rev_info log_tree_opt;
9
10 static int diff_tree_commit_sha1(const struct object_id *oid)
11 {
12         struct commit *commit = lookup_commit_reference(oid->hash);
13         if (!commit)
14                 return -1;
15         return log_tree_commit(&log_tree_opt, commit);
16 }
17
18 /* Diff one or more commits. */
19 static int stdin_diff_commit(struct commit *commit, const char *p)
20 {
21         struct object_id oid;
22         struct commit_list **pptr = NULL;
23
24         /* Graft the fake parents locally to the commit */
25         while (isspace(*p++) && !parse_oid_hex(p, &oid, &p)) {
26                 struct commit *parent = lookup_commit(oid.hash);
27                 if (!pptr) {
28                         /* Free the real parent list */
29                         free_commit_list(commit->parents);
30                         commit->parents = NULL;
31                         pptr = &(commit->parents);
32                 }
33                 if (parent) {
34                         pptr = &commit_list_insert(parent, pptr)->next;
35                 }
36         }
37         return log_tree_commit(&log_tree_opt, commit);
38 }
39
40 /* Diff two trees. */
41 static int stdin_diff_trees(struct tree *tree1, const char *p)
42 {
43         struct object_id oid;
44         struct tree *tree2;
45         if (!isspace(*p++) || parse_oid_hex(p, &oid, &p) || *p)
46                 return error("Need exactly two trees, separated by a space");
47         tree2 = lookup_tree(oid.hash);
48         if (!tree2 || parse_tree(tree2))
49                 return -1;
50         printf("%s %s\n", oid_to_hex(&tree1->object.oid),
51                           oid_to_hex(&tree2->object.oid));
52         diff_tree_sha1(tree1->object.oid.hash, tree2->object.oid.hash,
53                        "", &log_tree_opt.diffopt);
54         log_tree_diff_flush(&log_tree_opt);
55         return 0;
56 }
57
58 static int diff_tree_stdin(char *line)
59 {
60         int len = strlen(line);
61         struct object_id oid;
62         struct object *obj;
63         const char *p;
64
65         if (!len || line[len-1] != '\n')
66                 return -1;
67         line[len-1] = 0;
68         if (parse_oid_hex(line, &oid, &p))
69                 return -1;
70         obj = parse_object(oid.hash);
71         if (!obj)
72                 return -1;
73         if (obj->type == OBJ_COMMIT)
74                 return stdin_diff_commit((struct commit *)obj, p);
75         if (obj->type == OBJ_TREE)
76                 return stdin_diff_trees((struct tree *)obj, p);
77         error("Object %s is a %s, not a commit or tree",
78               oid_to_hex(&oid), typename(obj->type));
79         return -1;
80 }
81
82 static const char diff_tree_usage[] =
83 "git diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
84 "[<common-diff-options>] <tree-ish> [<tree-ish>] [<path>...]\n"
85 "  -r            diff recursively\n"
86 "  --root        include the initial commit as diff against /dev/null\n"
87 COMMON_DIFF_OPTIONS_HELP;
88
89 static void diff_tree_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
90 {
91         if (!rev->diffopt.output_format) {
92                 if (rev->dense_combined_merges)
93                         rev->diffopt.output_format = DIFF_FORMAT_PATCH;
94                 else
95                         rev->diffopt.output_format = DIFF_FORMAT_RAW;
96         }
97 }
98
99 int cmd_diff_tree(int argc, const char **argv, const char *prefix)
100 {
101         int nr_sha1;
102         char line[1000];
103         struct object *tree1, *tree2;
104         static struct rev_info *opt = &log_tree_opt;
105         struct setup_revision_opt s_r_opt;
106         int read_stdin = 0;
107
108         init_revisions(opt, prefix);
109         gitmodules_config();
110         git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
111         opt->abbrev = 0;
112         opt->diff = 1;
113         opt->disable_stdin = 1;
114         memset(&s_r_opt, 0, sizeof(s_r_opt));
115         s_r_opt.tweak = diff_tree_tweak_rev;
116
117         precompose_argv(argc, argv);
118         argc = setup_revisions(argc, argv, opt, &s_r_opt);
119
120         while (--argc > 0) {
121                 const char *arg = *++argv;
122
123                 if (!strcmp(arg, "--stdin")) {
124                         read_stdin = 1;
125                         continue;
126                 }
127                 usage(diff_tree_usage);
128         }
129
130         /*
131          * NOTE!  We expect "a..b" to expand to "^a b" but it is
132          * perfectly valid for revision range parser to yield "b ^a",
133          * which means the same thing. If we get the latter, i.e. the
134          * second one is marked UNINTERESTING, we recover the original
135          * order the user gave, i.e. "a..b", by swapping the trees.
136          */
137         nr_sha1 = opt->pending.nr;
138         switch (nr_sha1) {
139         case 0:
140                 if (!read_stdin)
141                         usage(diff_tree_usage);
142                 break;
143         case 1:
144                 tree1 = opt->pending.objects[0].item;
145                 diff_tree_commit_sha1(&tree1->oid);
146                 break;
147         case 2:
148                 tree1 = opt->pending.objects[0].item;
149                 tree2 = opt->pending.objects[1].item;
150                 if (tree2->flags & UNINTERESTING) {
151                         SWAP(tree2, tree1);
152                 }
153                 diff_tree_sha1(tree1->oid.hash,
154                                tree2->oid.hash,
155                                "", &opt->diffopt);
156                 log_tree_diff_flush(opt);
157                 break;
158         }
159
160         if (read_stdin) {
161                 int saved_nrl = 0;
162                 int saved_dcctc = 0;
163
164                 if (opt->diffopt.detect_rename)
165                         opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
166                                                DIFF_SETUP_USE_CACHE);
167                 while (fgets(line, sizeof(line), stdin)) {
168                         struct object_id oid;
169
170                         if (get_oid_hex(line, &oid)) {
171                                 fputs(line, stdout);
172                                 fflush(stdout);
173                         }
174                         else {
175                                 diff_tree_stdin(line);
176                                 if (saved_nrl < opt->diffopt.needed_rename_limit)
177                                         saved_nrl = opt->diffopt.needed_rename_limit;
178                                 if (opt->diffopt.degraded_cc_to_c)
179                                         saved_dcctc = 1;
180                         }
181                 }
182                 opt->diffopt.degraded_cc_to_c = saved_dcctc;
183                 opt->diffopt.needed_rename_limit = saved_nrl;
184         }
185
186         return diff_result_code(&opt->diffopt, 0);
187 }