Merge branch 'fixes'
[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 }