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