[PATCH] Prepare diffcore interface for diff-tree header supression.
[git/git.git] / diff-tree.c
1 #include <ctype.h>
2 #include "cache.h"
3 #include "diff.h"
4
5 static int silent = 0;
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 read_stdin = 0;
11 static int line_termination = '\n';
12 static int generate_patch = 0;
13 static int detect_rename = 0;
14 static int reverse_diff = 0;
15 static int diff_score_opt = 0;
16 static const char *pickaxe = NULL;
17 static const char *header = NULL;
18 static const char *header_prefix = "";
19
20 // What paths are we interested in?
21 static int nr_paths = 0;
22 static char **paths = NULL;
23 static int *pathlens = NULL;
24
25 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
26
27 static void update_tree_entry(void **bufp, unsigned long *sizep)
28 {
29 void *buf = *bufp;
30 unsigned long size = *sizep;
31 int len = strlen(buf) + 1 + 20;
32
33 if (size < len)
34 die("corrupt tree file");
35 *bufp = buf + len;
36 *sizep = size - len;
37 }
38
39 static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
40 {
41 int len = strlen(tree)+1;
42 const unsigned char *sha1 = tree + len;
43 const char *path = strchr(tree, ' ');
44
45 if (!path || size < len + 20 || sscanf(tree, "%o", modep) != 1)
46 die("corrupt tree file");
47 *pathp = path+1;
48 return sha1;
49 }
50
51 static char *malloc_base(const char *base, const char *path, int pathlen)
52 {
53 int baselen = strlen(base);
54 char *newbase = xmalloc(baselen + pathlen + 2);
55 memcpy(newbase, base, baselen);
56 memcpy(newbase + baselen, path, pathlen);
57 memcpy(newbase + baselen + pathlen, "/", 2);
58 return newbase;
59 }
60
61 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
62 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
63
64 /* A file entry went away or appeared */
65 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
66 {
67 unsigned mode;
68 const char *path;
69 const unsigned char *sha1 = extract(tree, size, &path, &mode);
70
71 if (header) {
72 printf("%s", header);
73 header = NULL;
74 }
75
76 if (silent)
77 return;
78
79 if (recursive && S_ISDIR(mode)) {
80 char type[20];
81 unsigned long size;
82 char *newbase = malloc_base(base, path, strlen(path));
83 void *tree;
84
85 tree = read_sha1_file(sha1, type, &size);
86 if (!tree || strcmp(type, "tree"))
87 die("corrupt tree sha %s", sha1_to_hex(sha1));
88
89 show_tree(prefix, tree, size, newbase);
90
91 free(tree);
92 free(newbase);
93 return;
94 }
95
96 diff_addremove(prefix[0], mode, sha1, base, path);
97 }
98
99 static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
100 {
101 unsigned mode1, mode2;
102 const char *path1, *path2;
103 const unsigned char *sha1, *sha2;
104 int cmp, pathlen1, pathlen2;
105
106 sha1 = extract(tree1, size1, &path1, &mode1);
107 sha2 = extract(tree2, size2, &path2, &mode2);
108
109 pathlen1 = strlen(path1);
110 pathlen2 = strlen(path2);
111 cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
112 if (cmp < 0) {
113 show_file("-", tree1, size1, base);
114 return -1;
115 }
116 if (cmp > 0) {
117 show_file("+", tree2, size2, base);
118 return 1;
119 }
120 if (!memcmp(sha1, sha2, 20) && mode1 == mode2)
121 return 0;
122
123 /*
124 * If the filemode has changed to/from a directory from/to a regular
125 * file, we need to consider it a remove and an add.
126 */
127 if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
128 show_file("-", tree1, size1, base);
129 show_file("+", tree2, size2, base);
130 return 0;
131 }
132
133 if (recursive && S_ISDIR(mode1)) {
134 int retval;
135 char *newbase = malloc_base(base, path1, pathlen1);
136 retval = diff_tree_sha1(sha1, sha2, newbase);
137 free(newbase);
138 return retval;
139 }
140
141 if (header) {
142 printf("%s", header);
143 header = NULL;
144 }
145 if (silent)
146 return 0;
147
148 diff_change(mode1, mode2, sha1, sha2, base, path1);
149 return 0;
150 }
151
152 static int interesting(void *tree, unsigned long size, const char *base)
153 {
154 const char *path;
155 unsigned mode;
156 int i;
157 int baselen, pathlen;
158
159 if (!nr_paths)
160 return 1;
161
162 (void)extract(tree, size, &path, &mode);
163
164 pathlen = strlen(path);
165 baselen = strlen(base);
166
167 for (i=0; i < nr_paths; i++) {
168 const char *match = paths[i];
169 int matchlen = pathlens[i];
170
171 if (baselen >= matchlen) {
172 /* If it doesn't match, move along... */
173 if (strncmp(base, match, matchlen))
174 continue;
175
176 /* The base is a subdirectory of a path which was specified. */
177 return 1;
178 }
179
180 /* Does the base match? */
181 if (strncmp(base, match, baselen))
182 continue;
183
184 match += baselen;
185 matchlen -= baselen;
186
187 if (pathlen > matchlen)
188 continue;
189
190 if (matchlen > pathlen) {
191 if (match[pathlen] != '/')
192 continue;
193 if (!S_ISDIR(mode))
194 continue;
195 }
196
197 if (strncmp(path, match, pathlen))
198 continue;
199
200 return 1;
201 }
202 return 0; /* No matches */
203 }
204
205 /* A whole sub-tree went away or appeared */
206 static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
207 {
208 while (size) {
209 if (interesting(tree, size, base))
210 show_file(prefix, tree, size, base);
211 update_tree_entry(&tree, &size);
212 }
213 }
214
215 static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
216 {
217 while (size1 | size2) {
218 if (nr_paths && size1 && !interesting(tree1, size1, base)) {
219 update_tree_entry(&tree1, &size1);
220 continue;
221 }
222 if (nr_paths && size2 && !interesting(tree2, size2, base)) {
223 update_tree_entry(&tree2, &size2);
224 continue;
225 }
226 if (!size1) {
227 show_file("+", tree2, size2, base);
228 update_tree_entry(&tree2, &size2);
229 continue;
230 }
231 if (!size2) {
232 show_file("-", tree1, size1, base);
233 update_tree_entry(&tree1, &size1);
234 continue;
235 }
236 switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
237 case -1:
238 update_tree_entry(&tree1, &size1);
239 continue;
240 case 0:
241 update_tree_entry(&tree1, &size1);
242 /* Fallthrough */
243 case 1:
244 update_tree_entry(&tree2, &size2);
245 continue;
246 }
247 die("git-diff-tree: internal error");
248 }
249 return 0;
250 }
251
252 static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
253 {
254 void *tree1, *tree2;
255 unsigned long size1, size2;
256 int retval;
257
258 tree1 = read_object_with_reference(old, "tree", &size1, NULL);
259 if (!tree1)
260 die("unable to read source tree (%s)", sha1_to_hex(old));
261 tree2 = read_object_with_reference(new, "tree", &size2, NULL);
262 if (!tree2)
263 die("unable to read destination tree (%s)", sha1_to_hex(new));
264 retval = diff_tree(tree1, size1, tree2, size2, base);
265 free(tree1);
266 free(tree2);
267 return retval;
268 }
269
270 static void call_diff_setup(void)
271 {
272 diff_setup(reverse_diff, (generate_patch ? -1 : line_termination));
273 }
274
275 static void call_diff_flush(void)
276 {
277 if (detect_rename)
278 diff_detect_rename(detect_rename, diff_score_opt);
279 if (pickaxe)
280 diff_pickaxe(pickaxe);
281 diff_flush(NULL, 0);
282 }
283
284 static int diff_tree_sha1_top(const unsigned char *old,
285 const unsigned char *new, const char *base)
286 {
287 int ret;
288
289 call_diff_setup();
290 ret = diff_tree_sha1(old, new, base);
291 call_diff_flush();
292 return ret;
293 }
294
295 static int diff_root_tree(const unsigned char *new, const char *base)
296 {
297 int retval;
298 void *tree;
299 unsigned long size;
300
301 call_diff_setup();
302 tree = read_object_with_reference(new, "tree", &size, NULL);
303 if (!tree)
304 die("unable to read root tree (%s)", sha1_to_hex(new));
305 retval = diff_tree("", 0, tree, size, base);
306 free(tree);
307 call_diff_flush();
308 return retval;
309 }
310
311 static int get_one_line(const char *msg, unsigned long len)
312 {
313 int ret = 0;
314
315 while (len--) {
316 ret++;
317 if (*msg++ == '\n')
318 break;
319 }
320 return ret;
321 }
322
323 static int add_author_info(char *buf, const char *line, int len)
324 {
325 char *date;
326 unsigned int namelen;
327 unsigned long time;
328 int tz;
329
330 line += strlen("author ");
331 date = strchr(line, '>');
332 if (!date)
333 return 0;
334 namelen = ++date - line;
335 time = strtoul(date, &date, 10);
336 tz = strtol(date, NULL, 10);
337
338 return sprintf(buf, "Author: %.*s\nDate: %s\n",
339 namelen, line,
340 show_date(time, tz));
341 }
342
343 static char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
344 {
345 static char this_header[16384];
346 int offset;
347
348 offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
349 if (verbose_header) {
350 int hdr = 1;
351
352 for (;;) {
353 const char *line = msg;
354 int linelen = get_one_line(msg, len);
355
356 if (!linelen)
357 break;
358
359 /*
360 * We want some slop for indentation and a possible
361 * final "...". Thus the "+ 20".
362 */
363 if (offset + linelen + 20 > sizeof(this_header)) {
364 memcpy(this_header + offset, " ...\n", 8);
365 offset += 8;
366 break;
367 }
368
369 msg += linelen;
370 len -= linelen;
371 if (linelen == 1)
372 hdr = 0;
373 if (hdr) {
374 if (!memcmp(line, "author ", 7))
375 offset += add_author_info(this_header + offset, line, linelen);
376 continue;
377 }
378 memset(this_header + offset, ' ', 4);
379 memcpy(this_header + offset + 4, line, linelen);
380 offset += linelen + 4;
381 }
382 /* Make sure there is an EOLN */
383 if (this_header[offset-1] != '\n')
384 this_header[offset++] = '\n';
385 /* Add _another_ EOLN if we are doing diff output */
386 if (!silent)
387 this_header[offset++] = '\n';
388 this_header[offset] = 0;
389 }
390
391 return this_header;
392 }
393
394 static int diff_tree_commit(const unsigned char *commit, const char *name)
395 {
396 unsigned long size, offset;
397 char *buf = read_object_with_reference(commit, "commit", &size, NULL);
398
399 if (!buf)
400 return -1;
401
402 if (!name) {
403 static char commit_name[60];
404 strcpy(commit_name, sha1_to_hex(commit));
405 name = commit_name;
406 }
407
408 /* Root commit? */
409 if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
410 header = generate_header(name, "root", buf, size);
411 diff_root_tree(commit, "");
412 }
413
414 /* More than one parent? */
415 if (ignore_merges) {
416 if (!memcmp(buf + 46 + 48, "parent ", 7))
417 return 0;
418 }
419
420 offset = 46;
421 while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
422 unsigned char parent[20];
423 if (get_sha1_hex(buf + offset + 7, parent))
424 return -1;
425 header = generate_header(name, sha1_to_hex(parent), buf, size);
426 diff_tree_sha1_top(parent, commit, "");
427 if (!header && verbose_header) {
428 header_prefix = "\ndiff-tree ";
429 /*
430 * Don't print multiple merge entries if we
431 * don't print the diffs.
432 */
433 if (silent)
434 break;
435 }
436 offset += 48;
437 }
438 return 0;
439 }
440
441 static int diff_tree_stdin(char *line)
442 {
443 int len = strlen(line);
444 unsigned char commit[20], parent[20];
445 static char this_header[1000];
446
447 if (!len || line[len-1] != '\n')
448 return -1;
449 line[len-1] = 0;
450 if (get_sha1_hex(line, commit))
451 return -1;
452 if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
453 line[40] = 0;
454 line[81] = 0;
455 sprintf(this_header, "%s (from %s)\n", line, line+41);
456 header = this_header;
457 return diff_tree_sha1_top(parent, commit, "");
458 }
459 line[40] = 0;
460 return diff_tree_commit(commit, line);
461 }
462
463 static char *diff_tree_usage =
464 "git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-C] [-R] [-S<string>] [-m] [-s] [-v] <tree-ish> <tree-ish>";
465
466 int main(int argc, char **argv)
467 {
468 int nr_sha1;
469 char line[1000];
470 unsigned char sha1[2][20];
471
472 nr_sha1 = 0;
473 for (;;) {
474 char *arg;
475
476 argv++;
477 argc--;
478 arg = *argv;
479 if (!arg)
480 break;
481
482 if (*arg != '-') {
483 if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
484 nr_sha1++;
485 continue;
486 }
487 break;
488 }
489
490 if (!strcmp(arg, "--")) {
491 argv++;
492 argc--;
493 break;
494 }
495 if (!strcmp(arg, "-r")) {
496 recursive = 1;
497 continue;
498 }
499 if (!strcmp(arg, "-R")) {
500 reverse_diff = 1;
501 continue;
502 }
503 if (!strcmp(arg, "-p")) {
504 recursive = generate_patch = 1;
505 continue;
506 }
507 if (!strncmp(arg, "-S", 2)) {
508 pickaxe = arg + 2;
509 continue;
510 }
511 if (!strncmp(arg, "-M", 2)) {
512 detect_rename = recursive = generate_patch = 1;
513 diff_score_opt = diff_scoreopt_parse(arg);
514 continue;
515 }
516 if (!strncmp(arg, "-C", 2)) {
517 detect_rename = 2;
518 recursive = generate_patch = 1;
519 diff_score_opt = diff_scoreopt_parse(arg);
520 continue;
521 }
522 if (!strcmp(arg, "-z")) {
523 line_termination = '\0';
524 continue;
525 }
526 if (!strcmp(arg, "-m")) {
527 ignore_merges = 0;
528 continue;
529 }
530 if (!strcmp(arg, "-s")) {
531 silent = 1;
532 continue;
533 }
534 if (!strcmp(arg, "-v")) {
535 verbose_header = 1;
536 header_prefix = "diff-tree ";
537 continue;
538 }
539 if (!strcmp(arg, "--stdin")) {
540 read_stdin = 1;
541 continue;
542 }
543 if (!strcmp(arg, "--root")) {
544 show_root_diff = 1;
545 continue;
546 }
547 usage(diff_tree_usage);
548 }
549
550 if (argc > 0) {
551 int i;
552
553 paths = argv;
554 nr_paths = argc;
555 pathlens = xmalloc(nr_paths * sizeof(int));
556 for (i=0; i<nr_paths; i++)
557 pathlens[i] = strlen(paths[i]);
558 }
559
560 switch (nr_sha1) {
561 case 0:
562 if (!read_stdin)
563 usage(diff_tree_usage);
564 break;
565 case 1:
566 diff_tree_commit(sha1[0], NULL);
567 break;
568 case 2:
569 diff_tree_sha1_top(sha1[0], sha1[1], "");
570 break;
571 }
572
573 if (!read_stdin)
574 return 0;
575
576 while (fgets(line, sizeof(line), stdin))
577 diff_tree_stdin(line);
578
579 return 0;
580 }