parse_pathspec: support prefixing original patterns
[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"
750f7b66 6#include "diffcore.h"
8e440259 7#include "tree.h"
ac1b3d12 8
48932677
NTND
9static void show_entry(struct diff_options *opt, const char *prefix,
10 struct tree_desc *desc, struct strbuf *base);
ac1b3d12 11
48932677
NTND
12static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2,
13 struct strbuf *base, struct diff_options *opt)
ac1b3d12
LT
14{
15 unsigned mode1, mode2;
16 const char *path1, *path2;
17 const unsigned char *sha1, *sha2;
18 int cmp, pathlen1, pathlen2;
48932677 19 int old_baselen = base->len;
ac1b3d12 20
50f9a858
LT
21 sha1 = tree_entry_extract(t1, &path1, &mode1);
22 sha2 = tree_entry_extract(t2, &path2, &mode2);
ac1b3d12 23
0de16337
NTND
24 pathlen1 = tree_entry_len(&t1->entry);
25 pathlen2 = tree_entry_len(&t2->entry);
ac1b3d12
LT
26 cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
27 if (cmp < 0) {
48932677 28 show_entry(opt, "-", t1, base);
ac1b3d12
LT
29 return -1;
30 }
31 if (cmp > 0) {
48932677 32 show_entry(opt, "+", t2, base);
ac1b3d12
LT
33 return 1;
34 }
8f67f8ae 35 if (!DIFF_OPT_TST(opt, FIND_COPIES_HARDER) && !hashcmp(sha1, sha2) && mode1 == mode2)
ac1b3d12
LT
36 return 0;
37
38 /*
39 * If the filemode has changed to/from a directory from/to a regular
40 * file, we need to consider it a remove and an add.
41 */
42 if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
48932677
NTND
43 show_entry(opt, "-", t1, base);
44 show_entry(opt, "+", t2, base);
ac1b3d12
LT
45 return 0;
46 }
47
48932677 48 strbuf_add(base, path1, pathlen1);
8f67f8ae 49 if (DIFF_OPT_TST(opt, RECURSIVE) && S_ISDIR(mode1)) {
fd55a19e 50 if (DIFF_OPT_TST(opt, TREE_IN_RECURSIVE)) {
ac1b3d12 51 opt->change(opt, mode1, mode2,
e5450100 52 sha1, sha2, 1, 1, base->buf, 0, 0);
fd55a19e 53 }
48932677 54 strbuf_addch(base, '/');
c0aa335c 55 diff_tree_sha1(sha1, sha2, base->buf, opt);
48932677 56 } else {
e5450100 57 opt->change(opt, mode1, mode2, sha1, sha2, 1, 1, base->buf, 0, 0);
ac1b3d12 58 }
48932677 59 strbuf_setlen(base, old_baselen);
ac1b3d12
LT
60 return 0;
61}
62
ac1b3d12 63/* A whole sub-tree went away or appeared */
48932677
NTND
64static void show_tree(struct diff_options *opt, const char *prefix,
65 struct tree_desc *desc, struct strbuf *base)
ac1b3d12 66{
d688cf07 67 enum interesting match = entry_not_interesting;
97d0b74a 68 for (; desc->size; update_tree_entry(desc)) {
d688cf07 69 if (match != all_entries_interesting) {
97d0b74a
NTND
70 match = tree_entry_interesting(&desc->entry, base, 0,
71 &opt->pathspec);
d688cf07 72 if (match == all_entries_not_interesting)
97d0b74a 73 break;
d688cf07 74 if (match == entry_not_interesting)
97d0b74a 75 continue;
1d848f64 76 }
97d0b74a 77 show_entry(opt, prefix, desc, base);
ac1b3d12
LT
78 }
79}
80
81/* A file entry went away or appeared */
48932677
NTND
82static void show_entry(struct diff_options *opt, const char *prefix,
83 struct tree_desc *desc, struct strbuf *base)
ac1b3d12
LT
84{
85 unsigned mode;
86 const char *path;
50f9a858 87 const unsigned char *sha1 = tree_entry_extract(desc, &path, &mode);
0de16337 88 int pathlen = tree_entry_len(&desc->entry);
48932677 89 int old_baselen = base->len;
ac1b3d12 90
48932677 91 strbuf_add(base, path, pathlen);
8f67f8ae 92 if (DIFF_OPT_TST(opt, RECURSIVE) && S_ISDIR(mode)) {
21666f1a 93 enum object_type type;
ac1b3d12
LT
94 struct tree_desc inner;
95 void *tree;
6fda5e51 96 unsigned long size;
ac1b3d12 97
6fda5e51 98 tree = read_sha1_file(sha1, &type, &size);
21666f1a 99 if (!tree || type != OBJ_TREE)
ac1b3d12
LT
100 die("corrupt tree sha %s", sha1_to_hex(sha1));
101
48932677 102 if (DIFF_OPT_TST(opt, TREE_IN_RECURSIVE))
e5450100 103 opt->add_remove(opt, *prefix, mode, sha1, 1, base->buf, 0);
df533f34 104
48932677 105 strbuf_addch(base, '/');
ac1b3d12 106
48932677
NTND
107 init_tree_desc(&inner, tree, size);
108 show_tree(opt, prefix, &inner, base);
ac1b3d12 109 free(tree);
48932677 110 } else
e5450100 111 opt->add_remove(opt, prefix[0], mode, sha1, 1, base->buf, 0);
48932677
NTND
112
113 strbuf_setlen(base, old_baselen);
ac1b3d12
LT
114}
115
48932677 116static void skip_uninteresting(struct tree_desc *t, struct strbuf *base,
d688cf07
NTND
117 struct diff_options *opt,
118 enum interesting *match)
5d865017
LT
119{
120 while (t->size) {
97d0b74a
NTND
121 *match = tree_entry_interesting(&t->entry, base, 0, &opt->pathspec);
122 if (*match) {
d688cf07 123 if (*match == all_entries_not_interesting)
97d0b74a
NTND
124 t->size = 0;
125 break;
5d865017 126 }
97d0b74a 127 update_tree_entry(t);
5d865017
LT
128 }
129}
130
48932677
NTND
131int diff_tree(struct tree_desc *t1, struct tree_desc *t2,
132 const char *base_str, struct diff_options *opt)
ac1b3d12 133{
48932677
NTND
134 struct strbuf base;
135 int baselen = strlen(base_str);
d688cf07
NTND
136 enum interesting t1_match = entry_not_interesting;
137 enum interesting t2_match = entry_not_interesting;
304de2d2 138
bc96cc87
NTND
139 /* Enable recursion indefinitely */
140 opt->pathspec.recursive = DIFF_OPT_TST(opt, RECURSIVE);
bc96cc87 141
48932677
NTND
142 strbuf_init(&base, PATH_MAX);
143 strbuf_add(&base, base_str, baselen);
144
5d865017 145 for (;;) {
28b9264d 146 if (diff_can_quit_early(opt))
822cac01 147 break;
66f13625 148 if (opt->pathspec.nr) {
97d0b74a
NTND
149 skip_uninteresting(t1, &base, opt, &t1_match);
150 skip_uninteresting(t2, &base, opt, &t2_match);
ac1b3d12
LT
151 }
152 if (!t1->size) {
5d865017
LT
153 if (!t2->size)
154 break;
48932677 155 show_entry(opt, "+", t2, &base);
ac1b3d12
LT
156 update_tree_entry(t2);
157 continue;
158 }
159 if (!t2->size) {
48932677 160 show_entry(opt, "-", t1, &base);
ac1b3d12
LT
161 update_tree_entry(t1);
162 continue;
163 }
48932677 164 switch (compare_tree_entry(t1, t2, &base, opt)) {
ac1b3d12
LT
165 case -1:
166 update_tree_entry(t1);
167 continue;
168 case 0:
169 update_tree_entry(t1);
170 /* Fallthrough */
171 case 1:
172 update_tree_entry(t2);
173 continue;
174 }
7e44c935 175 die("git diff-tree: internal error");
ac1b3d12 176 }
48932677
NTND
177
178 strbuf_release(&base);
ac1b3d12
LT
179 return 0;
180}
181
750f7b66
LT
182/*
183 * Does it look like the resulting diff might be due to a rename?
184 * - single entry
185 * - not a valid previous file
186 */
187static inline int diff_might_be_rename(void)
188{
189 return diff_queued_diff.nr == 1 &&
190 !DIFF_FILE_VALID(diff_queued_diff.queue[0]->one);
191}
192
193static void try_to_follow_renames(struct tree_desc *t1, struct tree_desc *t2, const char *base, struct diff_options *opt)
194{
195 struct diff_options diff_opts;
9f38e1ef
LT
196 struct diff_queue_struct *q = &diff_queued_diff;
197 struct diff_filepair *choice;
198 const char *paths[1];
750f7b66
LT
199 int i;
200
9f38e1ef
LT
201 /* Remove the file creation entry from the diff queue, and remember it */
202 choice = q->queue[0];
203 q->nr = 0;
204
750f7b66 205 diff_setup(&diff_opts);
8f67f8ae 206 DIFF_OPT_SET(&diff_opts, RECURSIVE);
0cdca133 207 DIFF_OPT_SET(&diff_opts, FIND_COPIES_HARDER);
750f7b66 208 diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
66f13625 209 diff_opts.single_follow = opt->pathspec.raw[0];
6dd4b66f 210 diff_opts.break_opt = opt->break_opt;
dd98d88b 211 diff_opts.rename_score = opt->rename_score;
750f7b66
LT
212 paths[0] = NULL;
213 diff_tree_setup_paths(paths, &diff_opts);
28452655 214 diff_setup_done(&diff_opts);
750f7b66
LT
215 diff_tree(t1, t2, base, &diff_opts);
216 diffcore_std(&diff_opts);
03b69c76 217 diff_tree_release_paths(&diff_opts);
750f7b66 218
9f38e1ef 219 /* Go through the new set of filepairing, and see if we find a more interesting one */
44c48a90 220 opt->found_follow = 0;
9f38e1ef
LT
221 for (i = 0; i < q->nr; i++) {
222 struct diff_filepair *p = q->queue[i];
750f7b66
LT
223
224 /*
225 * Found a source? Not only do we use that for the new
9f38e1ef 226 * diff_queued_diff, we will also use that as the path in
750f7b66
LT
227 * the future!
228 */
66f13625
NTND
229 if ((p->status == 'R' || p->status == 'C') &&
230 !strcmp(p->two->path, opt->pathspec.raw[0])) {
9f38e1ef
LT
231 /* Switch the file-pairs around */
232 q->queue[i] = choice;
233 choice = p;
234
235 /* Update the path we use from now on.. */
03b69c76 236 diff_tree_release_paths(opt);
66f13625
NTND
237 opt->pathspec.raw[0] = xstrdup(p->one->path);
238 diff_tree_setup_paths(opt->pathspec.raw, opt);
44c48a90
JH
239
240 /*
241 * The caller expects us to return a set of vanilla
242 * filepairs to let a later call to diffcore_std()
243 * it makes to sort the renames out (among other
244 * things), but we already have found renames
245 * ourselves; signal diffcore_std() not to muck with
246 * rename information.
247 */
248 opt->found_follow = 1;
750f7b66
LT
249 break;
250 }
251 }
252
253 /*
3ea3c215 254 * Then, discard all the non-relevant file pairs...
9f38e1ef
LT
255 */
256 for (i = 0; i < q->nr; i++) {
257 struct diff_filepair *p = q->queue[i];
258 diff_free_filepair(p);
259 }
260
261 /*
262 * .. and re-instate the one we want (which might be either the
263 * original one, or the rename/copy we found)
750f7b66 264 */
9f38e1ef
LT
265 q->queue[0] = choice;
266 q->nr = 1;
750f7b66
LT
267}
268
ac1b3d12
LT
269int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base, struct diff_options *opt)
270{
271 void *tree1, *tree2;
272 struct tree_desc t1, t2;
6fda5e51 273 unsigned long size1, size2;
ac1b3d12
LT
274 int retval;
275
6fda5e51 276 tree1 = read_object_with_reference(old, tree_type, &size1, NULL);
ac1b3d12
LT
277 if (!tree1)
278 die("unable to read source tree (%s)", sha1_to_hex(old));
6fda5e51 279 tree2 = read_object_with_reference(new, tree_type, &size2, NULL);
ac1b3d12
LT
280 if (!tree2)
281 die("unable to read destination tree (%s)", sha1_to_hex(new));
6fda5e51
LT
282 init_tree_desc(&t1, tree1, size1);
283 init_tree_desc(&t2, tree2, size2);
ac1b3d12 284 retval = diff_tree(&t1, &t2, base, opt);
39f75d26 285 if (!*base && DIFF_OPT_TST(opt, FOLLOW_RENAMES) && diff_might_be_rename()) {
750f7b66
LT
286 init_tree_desc(&t1, tree1, size1);
287 init_tree_desc(&t2, tree2, size2);
288 try_to_follow_renames(&t1, &t2, base, opt);
289 }
ac1b3d12
LT
290 free(tree1);
291 free(tree2);
292 return retval;
293}
294
2b60356d
RS
295int diff_root_tree_sha1(const unsigned char *new, const char *base, struct diff_options *opt)
296{
297 int retval;
298 void *tree;
6fda5e51 299 unsigned long size;
2b60356d
RS
300 struct tree_desc empty, real;
301
6fda5e51 302 tree = read_object_with_reference(new, tree_type, &size, NULL);
2b60356d
RS
303 if (!tree)
304 die("unable to read root tree (%s)", sha1_to_hex(new));
6fda5e51 305 init_tree_desc(&real, tree, size);
2b60356d 306
6fda5e51 307 init_tree_desc(&empty, "", 0);
2b60356d
RS
308 retval = diff_tree(&empty, &real, base, opt);
309 free(tree);
310 return retval;
311}
312
a8baa7b9 313void diff_tree_release_paths(struct diff_options *opt)
ac1b3d12 314{
66f13625 315 free_pathspec(&opt->pathspec);
a8baa7b9
JH
316}
317
318void diff_tree_setup_paths(const char **p, struct diff_options *opt)
319{
66f13625 320 init_pathspec(&opt->pathspec, p);
ac1b3d12 321}