1 /*
2  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/time.h>
18 #include <sys/queue.h>
19 #include <sys/resource.h>
20 
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <stdint.h>
24 #include <string.h>
25 #include <limits.h>
26 #include <sha1.h>
27 #include <sha2.h>
28 #include <zlib.h>
29 
30 #include "got_error.h"
31 #include "got_object.h"
32 
33 #include "got_lib_delta.h"
34 #include "got_lib_inflate.h"
35 #include "got_lib_object.h"
36 #include "got_lib_object_idset.h"
37 #include "got_lib_object_cache.h"
38 
39 /*
40  * XXX This should be reworked to track cache size and usage in bytes,
41  * rather than tracking N elements capped to a maximum element size.
42  */
43 #define GOT_OBJECT_CACHE_SIZE_OBJ	256
44 #define GOT_OBJECT_CACHE_SIZE_TREE	256
45 #define GOT_OBJECT_CACHE_SIZE_COMMIT	64
46 #define GOT_OBJECT_CACHE_SIZE_TAG	256
47 #define GOT_OBJECT_CACHE_SIZE_RAW	16
48 #define GOT_OBJECT_CACHE_MAX_ELEM_SIZE	1048576	/* 1 MB */
49 
50 const struct got_error *
51 got_object_cache_init(struct got_object_cache *cache,
52     enum got_object_cache_type type)
53 {
54 	struct rlimit rl;
55 
56 	memset(cache, 0, sizeof(*cache));
57 
58 	cache->idset = got_object_idset_alloc();
59 	if (cache->idset == NULL)
60 		return got_error_from_errno("got_object_idset_alloc");
61 
62 	cache->type = type;
63 	switch (type) {
64 	case GOT_OBJECT_CACHE_TYPE_OBJ:
65 		cache->size = GOT_OBJECT_CACHE_SIZE_OBJ;
66 		break;
67 	case GOT_OBJECT_CACHE_TYPE_TREE:
68 		cache->size = GOT_OBJECT_CACHE_SIZE_TREE;
69 		break;
70 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
71 		cache->size = GOT_OBJECT_CACHE_SIZE_COMMIT;
72 		break;
73 	case GOT_OBJECT_CACHE_TYPE_TAG:
74 		cache->size = GOT_OBJECT_CACHE_SIZE_TAG;
75 		break;
76 	case GOT_OBJECT_CACHE_TYPE_RAW:
77 		if (getrlimit(RLIMIT_NOFILE, &rl) == -1)
78 			return got_error_from_errno("getrlimit");
79 		cache->size = GOT_OBJECT_CACHE_SIZE_RAW;
80 		if (cache->size > rl.rlim_cur / 16)
81 			cache->size = rl.rlim_cur / 16;
82 		break;
83 	}
84 	return NULL;
85 }
86 
87 static size_t
88 get_size_obj(struct got_object *obj)
89 {
90 	size_t size = sizeof(*obj);
91 	struct got_delta *delta;
92 
93 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0)
94 		return size;
95 
96 	STAILQ_FOREACH(delta, &obj->deltas.entries, entry) {
97 		if (SIZE_MAX - sizeof(*delta) < size)
98 			return SIZE_MAX;
99 		size += sizeof(*delta);
100 	}
101 
102 	return size;
103 }
104 
105 static size_t
106 get_size_tree(struct got_tree_object *tree)
107 {
108 	size_t size = sizeof(*tree);
109 
110 	size += sizeof(struct got_tree_entry) * tree->nentries;
111 	return size;
112 }
113 
114 static size_t
115 get_size_commit(struct got_commit_object *commit)
116 {
117 	size_t size = sizeof(*commit);
118 	struct got_object_qid *qid;
119 
120 	size += sizeof(*commit->tree_id);
121 	size += strlen(commit->author);
122 	size += strlen(commit->committer);
123 	size += strlen(commit->logmsg);
124 
125 	STAILQ_FOREACH(qid, &commit->parent_ids, entry)
126 		size += sizeof(*qid) + sizeof(qid->id);
127 
128 	return size;
129 }
130 
131 static size_t
132 get_size_tag(struct got_tag_object *tag)
133 {
134 	size_t size = sizeof(*tag);
135 
136 	size += strlen(tag->tag);
137 	size += strlen(tag->tagger);
138 	size += strlen(tag->tagmsg);
139 
140 	return size;
141 }
142 
143 static size_t
144 get_size_raw(struct got_raw_object *raw)
145 {
146 	return sizeof(*raw);
147 }
148 
149 const struct got_error *
150 got_object_cache_add(struct got_object_cache *cache, struct got_object_id *id,
151     void *item)
152 {
153 	const struct got_error *err = NULL;
154 	struct got_object_cache_entry *ce;
155 	int nelem;
156 	size_t size;
157 
158 	switch (cache->type) {
159 	case GOT_OBJECT_CACHE_TYPE_OBJ:
160 		size = get_size_obj((struct got_object *)item);
161 		break;
162 	case GOT_OBJECT_CACHE_TYPE_TREE:
163 		size = get_size_tree((struct got_tree_object *)item);
164 		break;
165 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
166 		size = get_size_commit((struct got_commit_object *)item);
167 		break;
168 	case GOT_OBJECT_CACHE_TYPE_TAG:
169 		size = get_size_tag((struct got_tag_object *)item);
170 		break;
171 	case GOT_OBJECT_CACHE_TYPE_RAW:
172 		size = get_size_raw((struct got_raw_object *)item);
173 		break;
174 	default:
175 		return got_error(GOT_ERR_OBJ_TYPE);
176 	}
177 
178 	if (size > GOT_OBJECT_CACHE_MAX_ELEM_SIZE) {
179 #ifdef GOT_OBJ_CACHE_DEBUG
180 		char *id_str;
181 		if (got_object_id_str(&id_str, id) != NULL)
182 			return got_error_from_errno("got_object_id_str");
183 		fprintf(stderr, "%s: not caching ", getprogname());
184 		switch (cache->type) {
185 		case GOT_OBJECT_CACHE_TYPE_OBJ:
186 			fprintf(stderr, "object");
187 			break;
188 		case GOT_OBJECT_CACHE_TYPE_TREE:
189 			fprintf(stderr, "tree");
190 			break;
191 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
192 			fprintf(stderr, "commit");
193 			break;
194 		case GOT_OBJECT_CACHE_TYPE_TAG:
195 			fprintf(stderr, "tag");
196 			break;
197 		case GOT_OBJECT_CACHE_TYPE_RAW:
198 			fprintf(stderr, "raw");
199 			break;
200 		}
201 		fprintf(stderr, " %s (%zd bytes; %zd MB)\n", id_str, size,
202 		    size/1024/1024);
203 		free(id_str);
204 #endif
205 		cache->cache_toolarge++;
206 		return got_error(GOT_ERR_OBJ_TOO_LARGE);
207 	}
208 
209 	nelem = got_object_idset_num_elements(cache->idset);
210 	if (nelem >= cache->size) {
211 		err = got_object_idset_remove((void **)&ce,
212 		    cache->idset, NULL);
213 		if (err)
214 			return err;
215 		switch (cache->type) {
216 		case GOT_OBJECT_CACHE_TYPE_OBJ:
217 			got_object_close(ce->data.obj);
218 			break;
219 		case GOT_OBJECT_CACHE_TYPE_TREE:
220 			got_object_tree_close(ce->data.tree);
221 			break;
222 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
223 			got_object_commit_close(ce->data.commit);
224 			break;
225 		case GOT_OBJECT_CACHE_TYPE_TAG:
226 			got_object_tag_close(ce->data.tag);
227 			break;
228 		case GOT_OBJECT_CACHE_TYPE_RAW:
229 			got_object_raw_close(ce->data.raw);
230 			break;
231 		}
232 		memset(ce, 0, sizeof(*ce));
233 		cache->cache_evict++;
234 	} else {
235 		ce = malloc(sizeof(*ce));
236 		if (ce == NULL)
237 			return got_error_from_errno("malloc");
238 	}
239 
240 	memcpy(&ce->id, id, sizeof(ce->id));
241 	switch (cache->type) {
242 	case GOT_OBJECT_CACHE_TYPE_OBJ:
243 		ce->data.obj = (struct got_object *)item;
244 		break;
245 	case GOT_OBJECT_CACHE_TYPE_TREE:
246 		ce->data.tree = (struct got_tree_object *)item;
247 		break;
248 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
249 		ce->data.commit = (struct got_commit_object *)item;
250 		break;
251 	case GOT_OBJECT_CACHE_TYPE_TAG:
252 		ce->data.tag = (struct got_tag_object *)item;
253 		break;
254 	case GOT_OBJECT_CACHE_TYPE_RAW:
255 		ce->data.raw = (struct got_raw_object *)item;
256 		break;
257 	}
258 
259 	err = got_object_idset_add(cache->idset, id, ce);
260 	if (err)
261 		free(ce);
262 	else if (size > cache->max_cached_size)
263 		cache->max_cached_size = size;
264 	return err;
265 }
266 
267 void *
268 got_object_cache_get(struct got_object_cache *cache, struct got_object_id *id)
269 {
270 	struct got_object_cache_entry *ce;
271 
272 	cache->cache_searches++;
273 	ce = got_object_idset_get(cache->idset, id);
274 	if (ce) {
275 		cache->cache_hit++;
276 		switch (cache->type) {
277 		case GOT_OBJECT_CACHE_TYPE_OBJ:
278 			return ce->data.obj;
279 		case GOT_OBJECT_CACHE_TYPE_TREE:
280 			return ce->data.tree;
281 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
282 			return ce->data.commit;
283 		case GOT_OBJECT_CACHE_TYPE_TAG:
284 			return ce->data.tag;
285 		case GOT_OBJECT_CACHE_TYPE_RAW:
286 			return ce->data.raw;
287 		}
288 	}
289 
290 	cache->cache_miss++;
291 	return NULL;
292 }
293 
294 #ifdef GOT_OBJ_CACHE_DEBUG
295 static void
296 print_cache_stats(struct got_object_cache *cache, const char *name)
297 {
298 	fprintf(stderr, "%s: %s cache: %d elements, %d searches, %d hits, "
299 	    "%d missed, %d evicted, %d too large, max cached %zd bytes\n",
300 	    getprogname(), name,
301 	    cache->idset ? got_object_idset_num_elements(cache->idset) : -1,
302 	    cache->cache_searches, cache->cache_hit,
303 	    cache->cache_miss, cache->cache_evict, cache->cache_toolarge,
304 	    cache->max_cached_size);
305 }
306 
307 static const struct got_error *
308 check_refcount(struct got_object_id *id, void *data, void *arg)
309 {
310 	struct got_object_cache *cache = arg;
311 	struct got_object_cache_entry *ce = data;
312 	struct got_object *obj;
313 	struct got_tree_object *tree;
314 	struct got_commit_object *commit;
315 	struct got_tag_object *tag;
316 	struct got_raw_object *raw;
317 	char *id_str;
318 
319 	if (got_object_id_str(&id_str, id) != NULL)
320 		return NULL;
321 
322 	switch (cache->type) {
323 	case GOT_OBJECT_CACHE_TYPE_OBJ:
324 		obj = ce->data.obj;
325 		if (obj->refcnt == 1)
326 			break;
327 		fprintf(stderr, "object %s has %d unclaimed references\n",
328 		    id_str, obj->refcnt - 1);
329 		break;
330 	case GOT_OBJECT_CACHE_TYPE_TREE:
331 		tree = ce->data.tree;
332 		if (tree->refcnt == 1)
333 			break;
334 		fprintf(stderr, "tree %s has %d unclaimed references\n",
335 		    id_str, tree->refcnt - 1);
336 		break;
337 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
338 		commit = ce->data.commit;
339 		if (commit->refcnt == 1)
340 			break;
341 		fprintf(stderr, "commit %s has %d unclaimed references\n",
342 		    id_str, commit->refcnt - 1);
343 		break;
344 	case GOT_OBJECT_CACHE_TYPE_TAG:
345 		tag = ce->data.tag;
346 		if (tag->refcnt == 1)
347 			break;
348 		fprintf(stderr, "tag %s has %d unclaimed references\n",
349 		    id_str, tag->refcnt - 1);
350 		break;
351 	case GOT_OBJECT_CACHE_TYPE_RAW:
352 		raw = ce->data.raw;
353 		if (raw->refcnt == 1)
354 			break;
355 		fprintf(stderr, "raw %s has %d unclaimed references\n",
356 		    id_str, raw->refcnt - 1);
357 		break;
358 	}
359 	free(id_str);
360 	return NULL;
361 }
362 #endif
363 
364 static const struct got_error *
365 free_entry(struct got_object_id *id, void *data, void *arg)
366 {
367 	struct got_object_cache *cache = arg;
368 	struct got_object_cache_entry *ce = data;
369 
370 	switch (cache->type) {
371 	case GOT_OBJECT_CACHE_TYPE_OBJ:
372 		got_object_close(ce->data.obj);
373 		break;
374 	case GOT_OBJECT_CACHE_TYPE_TREE:
375 		got_object_tree_close(ce->data.tree);
376 		break;
377 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
378 		got_object_commit_close(ce->data.commit);
379 		break;
380 	case GOT_OBJECT_CACHE_TYPE_TAG:
381 		got_object_tag_close(ce->data.tag);
382 		break;
383 	case GOT_OBJECT_CACHE_TYPE_RAW:
384 		got_object_raw_close(ce->data.raw);
385 		break;
386 	}
387 
388 	free(ce);
389 
390 	return NULL;
391 }
392 
393 void
394 got_object_cache_close(struct got_object_cache *cache)
395 {
396 #ifdef GOT_OBJ_CACHE_DEBUG
397 	switch (cache->type) {
398 	case GOT_OBJECT_CACHE_TYPE_OBJ:
399 		print_cache_stats(cache, "object");
400 		break;
401 	case GOT_OBJECT_CACHE_TYPE_TREE:
402 		print_cache_stats(cache, "tree");
403 		break;
404 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
405 		print_cache_stats(cache, "commit");
406 		break;
407 	case GOT_OBJECT_CACHE_TYPE_TAG:
408 		print_cache_stats(cache, "tag");
409 		break;
410 	case GOT_OBJECT_CACHE_TYPE_RAW:
411 		print_cache_stats(cache, "raw");
412 		break;
413 	}
414 
415 	if (cache->idset)
416 		got_object_idset_for_each(cache->idset, check_refcount, cache);
417 #endif
418 
419 	if (cache->idset) {
420 		got_object_idset_for_each(cache->idset, free_entry, cache);
421 		got_object_idset_free(cache->idset);
422 		cache->idset = NULL;
423 	}
424 	cache->size = 0;
425 }