git-rev-list libification: rev-list walking
[git/git.git] / rev-list.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "tag.h"
4 #include "commit.h"
5 #include "tree.h"
6 #include "blob.h"
7 #include "epoch.h"
8 #include "diff.h"
9 #include "revision.h"
10
11 /* bits #0-2 in revision.h */
12
13 #define COUNTED (1u << 3)
14 #define SHOWN (1u << 4)
15 #define TMP_MARK (1u << 5) /* for isolated cases; clean after use */
16
17 static const char rev_list_usage[] =
18 "git-rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
19 " limiting output:\n"
20 " --max-count=nr\n"
21 " --max-age=epoch\n"
22 " --min-age=epoch\n"
23 " --sparse\n"
24 " --no-merges\n"
25 " --remove-empty\n"
26 " --all\n"
27 " ordering output:\n"
28 " --merge-order [ --show-breaks ]\n"
29 " --topo-order\n"
30 " --date-order\n"
31 " formatting output:\n"
32 " --parents\n"
33 " --objects | --objects-edge\n"
34 " --unpacked\n"
35 " --header | --pretty\n"
36 " --abbrev=nr | --no-abbrev\n"
37 " special purpose:\n"
38 " --bisect"
39 ;
40
41 struct rev_info revs;
42
43 static int bisect_list = 0;
44 static int verbose_header = 0;
45 static int abbrev = DEFAULT_ABBREV;
46 static int show_parents = 0;
47 static int hdr_termination = 0;
48 static const char *commit_prefix = "";
49 static enum cmit_fmt commit_format = CMIT_FMT_RAW;
50 static int merge_order = 0;
51 static int show_breaks = 0;
52 static int stop_traversal = 0;
53 static int no_merges = 0;
54
55 static void show_commit(struct commit *commit)
56 {
57 commit->object.flags |= SHOWN;
58 if (show_breaks) {
59 commit_prefix = "| ";
60 if (commit->object.flags & DISCONTINUITY) {
61 commit_prefix = "^ ";
62 } else if (commit->object.flags & BOUNDARY) {
63 commit_prefix = "= ";
64 }
65 }
66 printf("%s%s", commit_prefix, sha1_to_hex(commit->object.sha1));
67 if (show_parents) {
68 struct commit_list *parents = commit->parents;
69 while (parents) {
70 struct object *o = &(parents->item->object);
71 parents = parents->next;
72 if (o->flags & TMP_MARK)
73 continue;
74 printf(" %s", sha1_to_hex(o->sha1));
75 o->flags |= TMP_MARK;
76 }
77 /* TMP_MARK is a general purpose flag that can
78 * be used locally, but the user should clean
79 * things up after it is done with them.
80 */
81 for (parents = commit->parents;
82 parents;
83 parents = parents->next)
84 parents->item->object.flags &= ~TMP_MARK;
85 }
86 if (commit_format == CMIT_FMT_ONELINE)
87 putchar(' ');
88 else
89 putchar('\n');
90
91 if (verbose_header) {
92 static char pretty_header[16384];
93 pretty_print_commit(commit_format, commit, ~0, pretty_header, sizeof(pretty_header), abbrev);
94 printf("%s%c", pretty_header, hdr_termination);
95 }
96 fflush(stdout);
97 }
98
99 static int rewrite_one(struct commit **pp)
100 {
101 for (;;) {
102 struct commit *p = *pp;
103 if (p->object.flags & (TREECHANGE | UNINTERESTING))
104 return 0;
105 if (!p->parents)
106 return -1;
107 *pp = p->parents->item;
108 }
109 }
110
111 static void rewrite_parents(struct commit *commit)
112 {
113 struct commit_list **pp = &commit->parents;
114 while (*pp) {
115 struct commit_list *parent = *pp;
116 if (rewrite_one(&parent->item) < 0) {
117 *pp = parent->next;
118 continue;
119 }
120 pp = &parent->next;
121 }
122 }
123
124 static int filter_commit(struct commit * commit)
125 {
126 if (stop_traversal && (commit->object.flags & BOUNDARY))
127 return STOP;
128 if (commit->object.flags & (UNINTERESTING|SHOWN))
129 return CONTINUE;
130 if (revs.min_age != -1 && (commit->date > revs.min_age))
131 return CONTINUE;
132 if (revs.max_age != -1 && (commit->date < revs.max_age)) {
133 stop_traversal=1;
134 return CONTINUE;
135 }
136 if (no_merges && (commit->parents && commit->parents->next))
137 return CONTINUE;
138 if (revs.paths && revs.dense) {
139 if (!(commit->object.flags & TREECHANGE))
140 return CONTINUE;
141 rewrite_parents(commit);
142 }
143 return DO;
144 }
145
146 static int process_commit(struct commit * commit)
147 {
148 int action=filter_commit(commit);
149
150 if (action == STOP) {
151 return STOP;
152 }
153
154 if (action == CONTINUE) {
155 return CONTINUE;
156 }
157
158 if (revs.max_count != -1 && !revs.max_count--)
159 return STOP;
160
161 show_commit(commit);
162
163 return CONTINUE;
164 }
165
166 static struct object_list **process_blob(struct blob *blob,
167 struct object_list **p,
168 struct name_path *path,
169 const char *name)
170 {
171 struct object *obj = &blob->object;
172
173 if (!revs.blob_objects)
174 return p;
175 if (obj->flags & (UNINTERESTING | SEEN))
176 return p;
177 obj->flags |= SEEN;
178 return add_object(obj, p, path, name);
179 }
180
181 static struct object_list **process_tree(struct tree *tree,
182 struct object_list **p,
183 struct name_path *path,
184 const char *name)
185 {
186 struct object *obj = &tree->object;
187 struct tree_entry_list *entry;
188 struct name_path me;
189
190 if (!revs.tree_objects)
191 return p;
192 if (obj->flags & (UNINTERESTING | SEEN))
193 return p;
194 if (parse_tree(tree) < 0)
195 die("bad tree object %s", sha1_to_hex(obj->sha1));
196 obj->flags |= SEEN;
197 p = add_object(obj, p, path, name);
198 me.up = path;
199 me.elem = name;
200 me.elem_len = strlen(name);
201 entry = tree->entries;
202 tree->entries = NULL;
203 while (entry) {
204 struct tree_entry_list *next = entry->next;
205 if (entry->directory)
206 p = process_tree(entry->item.tree, p, &me, entry->name);
207 else
208 p = process_blob(entry->item.blob, p, &me, entry->name);
209 free(entry);
210 entry = next;
211 }
212 return p;
213 }
214
215 static void show_commit_list(struct rev_info *revs)
216 {
217 struct commit *commit;
218 struct object_list *objects = NULL, **p = &objects, *pending;
219
220 while ((commit = get_revision(revs)) != NULL) {
221 p = process_tree(commit->tree, p, NULL, "");
222 if (process_commit(commit) == STOP)
223 break;
224 }
225 for (pending = revs->pending_objects; pending; pending = pending->next) {
226 struct object *obj = pending->item;
227 const char *name = pending->name;
228 if (obj->flags & (UNINTERESTING | SEEN))
229 continue;
230 if (obj->type == tag_type) {
231 obj->flags |= SEEN;
232 p = add_object(obj, p, NULL, name);
233 continue;
234 }
235 if (obj->type == tree_type) {
236 p = process_tree((struct tree *)obj, p, NULL, name);
237 continue;
238 }
239 if (obj->type == blob_type) {
240 p = process_blob((struct blob *)obj, p, NULL, name);
241 continue;
242 }
243 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
244 }
245 while (objects) {
246 /* An object with name "foo\n0000000..." can be used to
247 * confuse downstream git-pack-objects very badly.
248 */
249 const char *ep = strchr(objects->name, '\n');
250 if (ep) {
251 printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
252 (int) (ep - objects->name),
253 objects->name);
254 }
255 else
256 printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
257 objects = objects->next;
258 }
259 }
260
261 /*
262 * This is a truly stupid algorithm, but it's only
263 * used for bisection, and we just don't care enough.
264 *
265 * We care just barely enough to avoid recursing for
266 * non-merge entries.
267 */
268 static int count_distance(struct commit_list *entry)
269 {
270 int nr = 0;
271
272 while (entry) {
273 struct commit *commit = entry->item;
274 struct commit_list *p;
275
276 if (commit->object.flags & (UNINTERESTING | COUNTED))
277 break;
278 if (!revs.paths || (commit->object.flags & TREECHANGE))
279 nr++;
280 commit->object.flags |= COUNTED;
281 p = commit->parents;
282 entry = p;
283 if (p) {
284 p = p->next;
285 while (p) {
286 nr += count_distance(p);
287 p = p->next;
288 }
289 }
290 }
291
292 return nr;
293 }
294
295 static void clear_distance(struct commit_list *list)
296 {
297 while (list) {
298 struct commit *commit = list->item;
299 commit->object.flags &= ~COUNTED;
300 list = list->next;
301 }
302 }
303
304 static struct commit_list *find_bisection(struct commit_list *list)
305 {
306 int nr, closest;
307 struct commit_list *p, *best;
308
309 nr = 0;
310 p = list;
311 while (p) {
312 if (!revs.paths || (p->item->object.flags & TREECHANGE))
313 nr++;
314 p = p->next;
315 }
316 closest = 0;
317 best = list;
318
319 for (p = list; p; p = p->next) {
320 int distance;
321
322 if (revs.paths && !(p->item->object.flags & TREECHANGE))
323 continue;
324
325 distance = count_distance(p);
326 clear_distance(list);
327 if (nr - distance < distance)
328 distance = nr - distance;
329 if (distance > closest) {
330 best = p;
331 closest = distance;
332 }
333 }
334 if (best)
335 best->next = NULL;
336 return best;
337 }
338
339 static void mark_edge_parents_uninteresting(struct commit *commit)
340 {
341 struct commit_list *parents;
342
343 for (parents = commit->parents; parents; parents = parents->next) {
344 struct commit *parent = parents->item;
345 if (!(parent->object.flags & UNINTERESTING))
346 continue;
347 mark_tree_uninteresting(parent->tree);
348 if (revs.edge_hint && !(parent->object.flags & SHOWN)) {
349 parent->object.flags |= SHOWN;
350 printf("-%s\n", sha1_to_hex(parent->object.sha1));
351 }
352 }
353 }
354
355 static void mark_edges_uninteresting(struct commit_list *list)
356 {
357 for ( ; list; list = list->next) {
358 struct commit *commit = list->item;
359
360 if (commit->object.flags & UNINTERESTING) {
361 mark_tree_uninteresting(commit->tree);
362 continue;
363 }
364 mark_edge_parents_uninteresting(commit);
365 }
366 }
367
368 int main(int argc, const char **argv)
369 {
370 struct commit_list *list;
371 int i;
372
373 argc = setup_revisions(argc, argv, &revs, NULL);
374
375 for (i = 1 ; i < argc; i++) {
376 const char *arg = argv[i];
377
378 /* accept -<digit>, like traditilnal "head" */
379 if ((*arg == '-') && isdigit(arg[1])) {
380 revs.max_count = atoi(arg + 1);
381 continue;
382 }
383 if (!strcmp(arg, "-n")) {
384 if (++i >= argc)
385 die("-n requires an argument");
386 revs.max_count = atoi(argv[i]);
387 continue;
388 }
389 if (!strncmp(arg,"-n",2)) {
390 revs.max_count = atoi(arg + 2);
391 continue;
392 }
393 if (!strcmp(arg, "--header")) {
394 verbose_header = 1;
395 continue;
396 }
397 if (!strcmp(arg, "--no-abbrev")) {
398 abbrev = 0;
399 continue;
400 }
401 if (!strncmp(arg, "--abbrev=", 9)) {
402 abbrev = strtoul(arg + 9, NULL, 10);
403 if (abbrev && abbrev < MINIMUM_ABBREV)
404 abbrev = MINIMUM_ABBREV;
405 else if (40 < abbrev)
406 abbrev = 40;
407 continue;
408 }
409 if (!strncmp(arg, "--pretty", 8)) {
410 commit_format = get_commit_format(arg+8);
411 verbose_header = 1;
412 hdr_termination = '\n';
413 if (commit_format == CMIT_FMT_ONELINE)
414 commit_prefix = "";
415 else
416 commit_prefix = "commit ";
417 continue;
418 }
419 if (!strncmp(arg, "--no-merges", 11)) {
420 no_merges = 1;
421 continue;
422 }
423 if (!strcmp(arg, "--parents")) {
424 show_parents = 1;
425 continue;
426 }
427 if (!strcmp(arg, "--bisect")) {
428 bisect_list = 1;
429 continue;
430 }
431 if (!strcmp(arg, "--merge-order")) {
432 merge_order = 1;
433 continue;
434 }
435 if (!strcmp(arg, "--show-breaks")) {
436 show_breaks = 1;
437 continue;
438 }
439 usage(rev_list_usage);
440
441 }
442
443 list = revs.commits;
444
445 if (!list &&
446 (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) && !revs.pending_objects))
447 usage(rev_list_usage);
448
449 prepare_revision_walk(&revs);
450 if (revs.tree_objects)
451 mark_edges_uninteresting(revs.commits);
452
453 if (bisect_list)
454 revs.commits = find_bisection(revs.commits);
455
456 save_commit_buffer = verbose_header;
457 track_object_refs = 0;
458
459 if (!merge_order) {
460 show_commit_list(&revs);
461 } else {
462 #ifndef NO_OPENSSL
463 if (sort_list_in_merge_order(list, &process_commit)) {
464 die("merge order sort failed\n");
465 }
466 #else
467 die("merge order sort unsupported, OpenSSL not linked");
468 #endif
469 }
470
471 return 0;
472 }