Trivial cleanup of track_tree_refs()
[git/git.git] / tree-diff.c
CommitLineData
ac1b3d12
LT
1/*
2 * Helper functions for tree diff generation
3 */
4#include "cache.h"
5#include "diff.h"
8e440259 6#include "tree.h"
ac1b3d12 7
304de2d2 8static char *malloc_base(const char *base, int baselen, const char *path, int pathlen)
ac1b3d12 9{
ac1b3d12
LT
10 char *newbase = xmalloc(baselen + pathlen + 2);
11 memcpy(newbase, base, baselen);
12 memcpy(newbase + baselen, path, pathlen);
13 memcpy(newbase + baselen + pathlen, "/", 2);
14 return newbase;
15}
16
cf995ede 17static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc,
304de2d2 18 const char *base, int baselen);
ac1b3d12 19
304de2d2 20static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const char *base, int baselen, struct diff_options *opt)
ac1b3d12
LT
21{
22 unsigned mode1, mode2;
23 const char *path1, *path2;
24 const unsigned char *sha1, *sha2;
25 int cmp, pathlen1, pathlen2;
26
50f9a858
LT
27 sha1 = tree_entry_extract(t1, &path1, &mode1);
28 sha2 = tree_entry_extract(t2, &path2, &mode2);
ac1b3d12 29
304de2d2
LT
30 pathlen1 = tree_entry_len(path1, sha1);
31 pathlen2 = tree_entry_len(path2, sha2);
ac1b3d12
LT
32 cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
33 if (cmp < 0) {
304de2d2 34 show_entry(opt, "-", t1, base, baselen);
ac1b3d12
LT
35 return -1;
36 }
37 if (cmp > 0) {
304de2d2 38 show_entry(opt, "+", t2, base, baselen);
ac1b3d12
LT
39 return 1;
40 }
a89fccd2 41 if (!opt->find_copies_harder && !hashcmp(sha1, sha2) && mode1 == mode2)
ac1b3d12
LT
42 return 0;
43
44 /*
45 * If the filemode has changed to/from a directory from/to a regular
46 * file, we need to consider it a remove and an add.
47 */
48 if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
304de2d2
LT
49 show_entry(opt, "-", t1, base, baselen);
50 show_entry(opt, "+", t2, base, baselen);
ac1b3d12
LT
51 return 0;
52 }
53
54 if (opt->recursive && S_ISDIR(mode1)) {
55 int retval;
304de2d2 56 char *newbase = malloc_base(base, baselen, path1, pathlen1);
ac1b3d12
LT
57 if (opt->tree_in_recursive)
58 opt->change(opt, mode1, mode2,
59 sha1, sha2, base, path1);
60 retval = diff_tree_sha1(sha1, sha2, newbase, opt);
61 free(newbase);
62 return retval;
63 }
64
65 opt->change(opt, mode1, mode2, sha1, sha2, base, path1);
66 return 0;
67}
68
304de2d2 69static int interesting(struct tree_desc *desc, const char *base, int baselen, struct diff_options *opt)
ac1b3d12
LT
70{
71 const char *path;
304de2d2 72 const unsigned char *sha1;
ac1b3d12
LT
73 unsigned mode;
74 int i;
304de2d2 75 int pathlen;
ac1b3d12 76
a8baa7b9 77 if (!opt->nr_paths)
ac1b3d12
LT
78 return 1;
79
304de2d2 80 sha1 = tree_entry_extract(desc, &path, &mode);
ac1b3d12 81
304de2d2 82 pathlen = tree_entry_len(path, sha1);
ac1b3d12 83
a8baa7b9
JH
84 for (i=0; i < opt->nr_paths; i++) {
85 const char *match = opt->paths[i];
86 int matchlen = opt->pathlens[i];
ac1b3d12
LT
87
88 if (baselen >= matchlen) {
89 /* If it doesn't match, move along... */
90 if (strncmp(base, match, matchlen))
91 continue;
92
93 /* The base is a subdirectory of a path which was specified. */
94 return 1;
95 }
96
97 /* Does the base match? */
98 if (strncmp(base, match, baselen))
99 continue;
100
101 match += baselen;
102 matchlen -= baselen;
103
104 if (pathlen > matchlen)
105 continue;
106
107 if (matchlen > pathlen) {
108 if (match[pathlen] != '/')
109 continue;
110 if (!S_ISDIR(mode))
111 continue;
112 }
113
114 if (strncmp(path, match, pathlen))
115 continue;
116
117 return 1;
118 }
119 return 0; /* No matches */
120}
121
122/* A whole sub-tree went away or appeared */
304de2d2 123static void show_tree(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base, int baselen)
ac1b3d12
LT
124{
125 while (desc->size) {
304de2d2
LT
126 if (interesting(desc, base, baselen, opt))
127 show_entry(opt, prefix, desc, base, baselen);
ac1b3d12
LT
128 update_tree_entry(desc);
129 }
130}
131
132/* A file entry went away or appeared */
cf995ede 133static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc,
304de2d2 134 const char *base, int baselen)
ac1b3d12
LT
135{
136 unsigned mode;
137 const char *path;
50f9a858 138 const unsigned char *sha1 = tree_entry_extract(desc, &path, &mode);
ac1b3d12
LT
139
140 if (opt->recursive && S_ISDIR(mode)) {
21666f1a 141 enum object_type type;
304de2d2
LT
142 int pathlen = tree_entry_len(path, sha1);
143 char *newbase = malloc_base(base, baselen, path, pathlen);
ac1b3d12
LT
144 struct tree_desc inner;
145 void *tree;
146
21666f1a
NP
147 tree = read_sha1_file(sha1, &type, &inner.size);
148 if (!tree || type != OBJ_TREE)
ac1b3d12
LT
149 die("corrupt tree sha %s", sha1_to_hex(sha1));
150
151 inner.buf = tree;
304de2d2 152 show_tree(opt, prefix, &inner, newbase, baselen + 1 + pathlen);
ac1b3d12
LT
153
154 free(tree);
155 free(newbase);
cf995ede
DR
156 } else {
157 opt->add_remove(opt, prefix[0], mode, sha1, base, path);
ac1b3d12 158 }
ac1b3d12
LT
159}
160
161int diff_tree(struct tree_desc *t1, struct tree_desc *t2, const char *base, struct diff_options *opt)
162{
304de2d2
LT
163 int baselen = strlen(base);
164
ac1b3d12 165 while (t1->size | t2->size) {
822cac01
JH
166 if (opt->quiet && opt->has_changes)
167 break;
304de2d2 168 if (opt->nr_paths && t1->size && !interesting(t1, base, baselen, opt)) {
ac1b3d12
LT
169 update_tree_entry(t1);
170 continue;
171 }
304de2d2 172 if (opt->nr_paths && t2->size && !interesting(t2, base, baselen, opt)) {
ac1b3d12
LT
173 update_tree_entry(t2);
174 continue;
175 }
176 if (!t1->size) {
304de2d2 177 show_entry(opt, "+", t2, base, baselen);
ac1b3d12
LT
178 update_tree_entry(t2);
179 continue;
180 }
181 if (!t2->size) {
304de2d2 182 show_entry(opt, "-", t1, base, baselen);
ac1b3d12
LT
183 update_tree_entry(t1);
184 continue;
185 }
304de2d2 186 switch (compare_tree_entry(t1, t2, base, baselen, opt)) {
ac1b3d12
LT
187 case -1:
188 update_tree_entry(t1);
189 continue;
190 case 0:
191 update_tree_entry(t1);
192 /* Fallthrough */
193 case 1:
194 update_tree_entry(t2);
195 continue;
196 }
197 die("git-diff-tree: internal error");
198 }
199 return 0;
200}
201
202int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base, struct diff_options *opt)
203{
204 void *tree1, *tree2;
205 struct tree_desc t1, t2;
206 int retval;
207
8e440259 208 tree1 = read_object_with_reference(old, tree_type, &t1.size, NULL);
ac1b3d12
LT
209 if (!tree1)
210 die("unable to read source tree (%s)", sha1_to_hex(old));
8e440259 211 tree2 = read_object_with_reference(new, tree_type, &t2.size, NULL);
ac1b3d12
LT
212 if (!tree2)
213 die("unable to read destination tree (%s)", sha1_to_hex(new));
214 t1.buf = tree1;
215 t2.buf = tree2;
216 retval = diff_tree(&t1, &t2, base, opt);
217 free(tree1);
218 free(tree2);
219 return retval;
220}
221
2b60356d
RS
222int diff_root_tree_sha1(const unsigned char *new, const char *base, struct diff_options *opt)
223{
224 int retval;
225 void *tree;
226 struct tree_desc empty, real;
227
228 tree = read_object_with_reference(new, tree_type, &real.size, NULL);
229 if (!tree)
230 die("unable to read root tree (%s)", sha1_to_hex(new));
231 real.buf = tree;
232
233 empty.size = 0;
234 empty.buf = "";
235 retval = diff_tree(&empty, &real, base, opt);
236 free(tree);
237 return retval;
238}
239
ac1b3d12
LT
240static int count_paths(const char **paths)
241{
242 int i = 0;
243 while (*paths++)
244 i++;
245 return i;
246}
247
a8baa7b9 248void diff_tree_release_paths(struct diff_options *opt)
ac1b3d12 249{
a8baa7b9
JH
250 free(opt->pathlens);
251}
252
253void diff_tree_setup_paths(const char **p, struct diff_options *opt)
254{
255 opt->nr_paths = 0;
256 opt->pathlens = NULL;
257 opt->paths = NULL;
258
ac1b3d12
LT
259 if (p) {
260 int i;
261
a8baa7b9
JH
262 opt->paths = p;
263 opt->nr_paths = count_paths(p);
264 if (opt->nr_paths == 0) {
265 opt->pathlens = NULL;
7e4a2a84
JH
266 return;
267 }
a8baa7b9
JH
268 opt->pathlens = xmalloc(opt->nr_paths * sizeof(int));
269 for (i=0; i < opt->nr_paths; i++)
270 opt->pathlens[i] = strlen(p[i]);
ac1b3d12
LT
271 }
272}