Diff clean-up.
[git/git.git] / diff-tree.c
1 #include <ctype.h>
2 #include "cache.h"
3 #include "diff.h"
4 #include "commit.h"
5
6 static int show_root_diff = 0;
7 static int verbose_header = 0;
8 static int ignore_merges = 1;
9 static int recursive = 0;
10 static int show_tree_entry_in_recursive = 0;
11 static int read_stdin = 0;
12
13 static struct diff_options diff_options;
14
15 static const char *header = NULL;
16 static const char *header_prefix = "";
17 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
18
19 // What paths are we interested in?
20 static int nr_paths = 0;
21 static const char **paths = NULL;
22 static int *pathlens = NULL;
23
24 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
25
26 static void update_tree_entry(void **bufp, unsigned long *sizep)
27 {
28 void *buf = *bufp;
29 unsigned long size = *sizep;
30 int len = strlen(buf) + 1 + 20;
31
32 if (size < len)
33 die("corrupt tree file");
34 *bufp = buf + len;
35 *sizep = size - len;
36 }
37
38 static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
39 {
40 int len = strlen(tree)+1;
41 const unsigned char *sha1 = tree + len;
42 const char *path = strchr(tree, ' ');
43 unsigned int mode;
44
45 if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
46 die("corrupt tree file");
47 *pathp = path+1;
48 *modep = DIFF_FILE_CANON_MODE(mode);
49 return sha1;
50 }
51
52 static char *malloc_base(const char *base, const char *path, int pathlen)
53 {
54 int baselen = strlen(base);
55 char *newbase = xmalloc(baselen + pathlen + 2);
56 memcpy(newbase, base, baselen);
57 memcpy(newbase + baselen, path, pathlen);
58 memcpy(newbase + baselen + pathlen, "/", 2);
59 return newbase;
60 }
61
62 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
63 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
64
65 /* A file entry went away or appeared */
66 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
67 {
68 unsigned mode;
69 const char *path;
70 const unsigned char *sha1 = extract(tree, size, &path, &mode);
71
72 if (recursive && S_ISDIR(mode)) {
73 char type[20];
74 unsigned long size;
75 char *newbase = malloc_base(base, path, strlen(path));
76 void *tree;
77
78 tree = read_sha1_file(sha1, type, &size);
79 if (!tree || strcmp(type, "tree"))
80 die("corrupt tree sha %s", sha1_to_hex(sha1));
81
82 show_tree(prefix, tree, size, newbase);
83
84 free(tree);
85 free(newbase);
86 return;
87 }
88
89 diff_addremove(&diff_options, prefix[0], mode, sha1, base, path);
90 }
91
92 static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
93 {
94 unsigned mode1, mode2;
95 const char *path1, *path2;
96 const unsigned char *sha1, *sha2;
97 int cmp, pathlen1, pathlen2;
98
99 sha1 = extract(tree1, size1, &path1, &mode1);
100 sha2 = extract(tree2, size2, &path2, &mode2);
101
102 pathlen1 = strlen(path1);
103 pathlen2 = strlen(path2);
104 cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
105 if (cmp < 0) {
106 show_file("-", tree1, size1, base);
107 return -1;
108 }
109 if (cmp > 0) {
110 show_file("+", tree2, size2, base);
111 return 1;
112 }
113 if (!diff_options.find_copies_harder &&
114 !memcmp(sha1, sha2, 20) && mode1 == mode2)
115 return 0;
116
117 /*
118 * If the filemode has changed to/from a directory from/to a regular
119 * file, we need to consider it a remove and an add.
120 */
121 if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
122 show_file("-", tree1, size1, base);
123 show_file("+", tree2, size2, base);
124 return 0;
125 }
126
127 if (recursive && S_ISDIR(mode1)) {
128 int retval;
129 char *newbase = malloc_base(base, path1, pathlen1);
130 if (show_tree_entry_in_recursive)
131 diff_change(&diff_options, mode1, mode2,
132 sha1, sha2, base, path1);
133 retval = diff_tree_sha1(sha1, sha2, newbase);
134 free(newbase);
135 return retval;
136 }
137
138 diff_change(&diff_options, mode1, mode2, sha1, sha2, base, path1);
139 return 0;
140 }
141
142 static int interesting(void *tree, unsigned long size, const char *base)
143 {
144 const char *path;
145 unsigned mode;
146 int i;
147 int baselen, pathlen;
148
149 if (!nr_paths)
150 return 1;
151
152 (void)extract(tree, size, &path, &mode);
153
154 pathlen = strlen(path);
155 baselen = strlen(base);
156
157 for (i=0; i < nr_paths; i++) {
158 const char *match = paths[i];
159 int matchlen = pathlens[i];
160
161 if (baselen >= matchlen) {
162 /* If it doesn't match, move along... */
163 if (strncmp(base, match, matchlen))
164 continue;
165
166 /* The base is a subdirectory of a path which was specified. */
167 return 1;
168 }
169
170 /* Does the base match? */
171 if (strncmp(base, match, baselen))
172 continue;
173
174 match += baselen;
175 matchlen -= baselen;
176
177 if (pathlen > matchlen)
178 continue;
179
180 if (matchlen > pathlen) {
181 if (match[pathlen] != '/')
182 continue;
183 if (!S_ISDIR(mode))
184 continue;
185 }
186
187 if (strncmp(path, match, pathlen))
188 continue;
189
190 return 1;
191 }
192 return 0; /* No matches */
193 }
194
195 /* A whole sub-tree went away or appeared */
196 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
197 {
198 while (size) {
199 if (interesting(tree, size, base))
200 show_file(prefix, tree, size, base);
201 update_tree_entry(&tree, &size);
202 }
203 }
204
205 static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
206 {
207 while (size1 | size2) {
208 if (nr_paths && size1 && !interesting(tree1, size1, base)) {
209 update_tree_entry(&tree1, &size1);
210 continue;
211 }
212 if (nr_paths && size2 && !interesting(tree2, size2, base)) {
213 update_tree_entry(&tree2, &size2);
214 continue;
215 }
216 if (!size1) {
217 show_file("+", tree2, size2, base);
218 update_tree_entry(&tree2, &size2);
219 continue;
220 }
221 if (!size2) {
222 show_file("-", tree1, size1, base);
223 update_tree_entry(&tree1, &size1);
224 continue;
225 }
226 switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
227 case -1:
228 update_tree_entry(&tree1, &size1);
229 continue;
230 case 0:
231 update_tree_entry(&tree1, &size1);
232 /* Fallthrough */
233 case 1:
234 update_tree_entry(&tree2, &size2);
235 continue;
236 }
237 die("git-diff-tree: internal error");
238 }
239 return 0;
240 }
241
242 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
243 {
244 void *tree1, *tree2;
245 unsigned long size1, size2;
246 int retval;
247
248 tree1 = read_object_with_reference(old, "tree", &size1, NULL);
249 if (!tree1)
250 die("unable to read source tree (%s)", sha1_to_hex(old));
251 tree2 = read_object_with_reference(new, "tree", &size2, NULL);
252 if (!tree2)
253 die("unable to read destination tree (%s)", sha1_to_hex(new));
254 retval = diff_tree(tree1, size1, tree2, size2, base);
255 free(tree1);
256 free(tree2);
257 return retval;
258 }
259
260 static void call_diff_setup_done(void)
261 {
262 diff_setup_done(&diff_options);
263 }
264
265 static int call_diff_flush(void)
266 {
267 diffcore_std(&diff_options);
268 if (diff_queue_is_empty()) {
269 int saved_fmt = diff_options.output_format;
270 diff_options.output_format = DIFF_FORMAT_NO_OUTPUT;
271 diff_flush(&diff_options);
272 diff_options.output_format = saved_fmt;
273 return 0;
274 }
275 if (header) {
276 printf("%s%c", header, diff_options.line_termination);
277 header = NULL;
278 }
279 diff_flush(&diff_options);
280 return 1;
281 }
282
283 static int diff_tree_sha1_top(const unsigned char *old,
284 const unsigned char *new, const char *base)
285 {
286 int ret;
287
288 call_diff_setup_done();
289 ret = diff_tree_sha1(old, new, base);
290 call_diff_flush();
291 return ret;
292 }
293
294 static int diff_root_tree(const unsigned char *new, const char *base)
295 {
296 int retval;
297 void *tree;
298 unsigned long size;
299
300 call_diff_setup_done();
301 tree = read_object_with_reference(new, "tree", &size, NULL);
302 if (!tree)
303 die("unable to read root tree (%s)", sha1_to_hex(new));
304 retval = diff_tree("", 0, tree, size, base);
305 free(tree);
306 call_diff_flush();
307 return retval;
308 }
309
310 static const char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
311 {
312 static char this_header[16384];
313 int offset;
314
315 if (!verbose_header)
316 return commit;
317
318 offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
319 offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
320 return this_header;
321 }
322
323 static int diff_tree_commit(const unsigned char *commit, const char *name)
324 {
325 unsigned long size, offset;
326 char *buf = read_object_with_reference(commit, "commit", &size, NULL);
327
328 if (!buf)
329 return -1;
330
331 if (!name) {
332 static char commit_name[60];
333 strcpy(commit_name, sha1_to_hex(commit));
334 name = commit_name;
335 }
336
337 /* Root commit? */
338 if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
339 header = generate_header(name, "root", buf, size);
340 diff_root_tree(commit, "");
341 }
342
343 /* More than one parent? */
344 if (ignore_merges) {
345 if (!memcmp(buf + 46 + 48, "parent ", 7))
346 return 0;
347 }
348
349 offset = 46;
350 while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
351 unsigned char parent[20];
352 if (get_sha1_hex(buf + offset + 7, parent))
353 return -1;
354 header = generate_header(name, sha1_to_hex(parent), buf, size);
355 diff_tree_sha1_top(parent, commit, "");
356 if (!header && verbose_header) {
357 header_prefix = "\ndiff-tree ";
358 /*
359 * Don't print multiple merge entries if we
360 * don't print the diffs.
361 */
362 }
363 offset += 48;
364 }
365 free(buf);
366 return 0;
367 }
368
369 static int diff_tree_stdin(char *line)
370 {
371 int len = strlen(line);
372 unsigned char commit[20], parent[20];
373 static char this_header[1000];
374
375 if (!len || line[len-1] != '\n')
376 return -1;
377 line[len-1] = 0;
378 if (get_sha1_hex(line, commit))
379 return -1;
380 if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
381 line[40] = 0;
382 line[81] = 0;
383 sprintf(this_header, "%s (from %s)\n", line, line+41);
384 header = this_header;
385 return diff_tree_sha1_top(parent, commit, "");
386 }
387 line[40] = 0;
388 return diff_tree_commit(commit, line);
389 }
390
391 static int count_paths(const char **paths)
392 {
393 int i = 0;
394 while (*paths++)
395 i++;
396 return i;
397 }
398
399 static const char diff_tree_usage[] =
400 "git-diff-tree [--stdin] [-m] [-s] [-v] [--pretty] [-t] "
401 "[<common diff options>] <tree-ish> <tree-ish>"
402 COMMON_DIFF_OPTIONS_HELP;
403
404 int main(int argc, const char **argv)
405 {
406 int nr_sha1;
407 char line[1000];
408 unsigned char sha1[2][20];
409 const char *prefix = setup_git_directory();
410
411 nr_sha1 = 0;
412 diff_setup(&diff_options);
413
414 for (;;) {
415 int diff_opt_cnt;
416 const char *arg;
417
418 argv++;
419 argc--;
420 arg = *argv;
421 if (!arg)
422 break;
423
424 if (*arg != '-') {
425 if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
426 nr_sha1++;
427 continue;
428 }
429 break;
430 }
431
432 diff_opt_cnt = diff_opt_parse(&diff_options, argv, argc);
433 if (diff_opt_cnt < 0)
434 usage(diff_tree_usage);
435 else if (diff_opt_cnt) {
436 argv += diff_opt_cnt - 1;
437 argc -= diff_opt_cnt - 1;
438 continue;
439 }
440
441
442 if (!strcmp(arg, "--")) {
443 argv++;
444 argc--;
445 break;
446 }
447 if (!strcmp(arg, "-r")) {
448 recursive = 1;
449 continue;
450 }
451 if (!strcmp(arg, "-t")) {
452 recursive = show_tree_entry_in_recursive = 1;
453 continue;
454 }
455 if (!strcmp(arg, "-m")) {
456 ignore_merges = 0;
457 continue;
458 }
459 if (!strcmp(arg, "-v")) {
460 verbose_header = 1;
461 header_prefix = "diff-tree ";
462 continue;
463 }
464 if (!strncmp(arg, "--pretty", 8)) {
465 verbose_header = 1;
466 header_prefix = "diff-tree ";
467 commit_format = get_commit_format(arg+8);
468 continue;
469 }
470 if (!strcmp(arg, "--stdin")) {
471 read_stdin = 1;
472 continue;
473 }
474 if (!strcmp(arg, "--root")) {
475 show_root_diff = 1;
476 continue;
477 }
478 usage(diff_tree_usage);
479 }
480 if (diff_options.output_format == DIFF_FORMAT_PATCH)
481 recursive = 1;
482
483 paths = get_pathspec(prefix, argv);
484 if (paths) {
485 int i;
486
487 nr_paths = count_paths(paths);
488 pathlens = xmalloc(nr_paths * sizeof(int));
489 for (i=0; i<nr_paths; i++)
490 pathlens[i] = strlen(paths[i]);
491 }
492
493 switch (nr_sha1) {
494 case 0:
495 if (!read_stdin)
496 usage(diff_tree_usage);
497 break;
498 case 1:
499 diff_tree_commit(sha1[0], NULL);
500 break;
501 case 2:
502 diff_tree_sha1_top(sha1[0], sha1[1], "");
503 break;
504 }
505
506 if (!read_stdin)
507 return 0;
508
509 if (diff_options.detect_rename)
510 diff_options.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
511 DIFF_SETUP_USE_CACHE);
512 while (fgets(line, sizeof(line), stdin))
513 diff_tree_stdin(line);
514
515 return 0;
516 }