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/resource.h>
19 
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <stdint.h>
23 #include <string.h>
24 #include <limits.h>
25 #include <zlib.h>
26 
27 #include "got_error.h"
28 #include "got_object.h"
29 
30 #include "got_lib_delta.h"
31 #include "got_lib_inflate.h"
32 #include "got_lib_object.h"
33 #include "got_lib_object_idset.h"
34 #include "got_lib_object_cache.h"
35 
36 /*
37  * XXX This should be reworked to track cache size and usage in bytes,
38  * rather than tracking N elements capped to a maximum element size.
39  */
40 #define GOT_OBJECT_CACHE_SIZE_OBJ	256
41 #define GOT_OBJECT_CACHE_SIZE_TREE	256
42 #define GOT_OBJECT_CACHE_SIZE_COMMIT	64
43 #define GOT_OBJECT_CACHE_SIZE_TAG	2048
44 #define GOT_OBJECT_CACHE_SIZE_RAW	64
45 #define GOT_OBJECT_CACHE_MAX_ELEM_SIZE	1048576	/* 1 MB */
46 
47 const struct got_error *
48 got_object_cache_init(struct got_object_cache *cache,
49     enum got_object_cache_type type)
50 {
51 	struct rlimit rl;
52 
53 	memset(cache, 0, sizeof(*cache));
54 
55 	cache->idset = got_object_idset_alloc();
56 	if (cache->idset == NULL)
57 		return got_error_from_errno("got_object_idset_alloc");
58 
59 	cache->type = type;
60 	switch (type) {
61 	case GOT_OBJECT_CACHE_TYPE_OBJ:
62 		cache->size = GOT_OBJECT_CACHE_SIZE_OBJ;
63 		break;
64 	case GOT_OBJECT_CACHE_TYPE_TREE:
65 		cache->size = GOT_OBJECT_CACHE_SIZE_TREE;
66 		break;
67 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
68 		cache->size = GOT_OBJECT_CACHE_SIZE_COMMIT;
69 		break;
70 	case GOT_OBJECT_CACHE_TYPE_TAG:
71 		cache->size = GOT_OBJECT_CACHE_SIZE_TAG;
72 		break;
73 	case GOT_OBJECT_CACHE_TYPE_RAW:
74 		if (getrlimit(RLIMIT_NOFILE, &rl) == -1)
75 			return got_error_from_errno("getrlimit");
76 		cache->size = GOT_OBJECT_CACHE_SIZE_RAW;
77 		if (cache->size > rl.rlim_cur / 16)
78 			cache->size = rl.rlim_cur / 16;
79 		break;
80 	}
81 	return NULL;
82 }
83 
84 size_t
85 get_size_obj(struct got_object *obj)
86 {
87 	size_t size = sizeof(*obj);
88 	struct got_delta *delta;
89 
90 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0)
91 		return size;
92 
93 	STAILQ_FOREACH(delta, &obj->deltas.entries, entry) {
94 		if (SIZE_MAX - sizeof(*delta) < size)
95 			return SIZE_MAX;
96 		size += sizeof(*delta);
97 	}
98 
99 	return size;
100 }
101 
102 size_t
103 get_size_tree(struct got_tree_object *tree)
104 {
105 	size_t size = sizeof(*tree);
106 
107 	size += sizeof(struct got_tree_entry) * tree->nentries;
108 	return size;
109 }
110 
111 size_t
112 get_size_commit(struct got_commit_object *commit)
113 {
114 	size_t size = sizeof(*commit);
115 	struct got_object_qid *qid;
116 
117 	size += sizeof(*commit->tree_id);
118 	size += strlen(commit->author);
119 	size += strlen(commit->committer);
120 	size += strlen(commit->logmsg);
121 
122 	STAILQ_FOREACH(qid, &commit->parent_ids, entry)
123 		size += sizeof(*qid) + sizeof(*qid->id);
124 
125 	return size;
126 }
127 
128 size_t
129 get_size_tag(struct got_tag_object *tag)
130 {
131 	size_t size = sizeof(*tag);
132 
133 	size += strlen(tag->tag);
134 	size += strlen(tag->tagger);
135 	size += strlen(tag->tagmsg);
136 
137 	return size;
138 }
139 
140 size_t
141 get_size_raw(struct got_raw_object *raw)
142 {
143 	return sizeof(*raw);
144 }
145 
146 const struct got_error *
147 got_object_cache_add(struct got_object_cache *cache, struct got_object_id *id, void *item)
148 {
149 	const struct got_error *err = NULL;
150 	struct got_object_cache_entry *ce;
151 	int nelem;
152 	size_t size;
153 
154 	switch (cache->type) {
155 	case GOT_OBJECT_CACHE_TYPE_OBJ:
156 		size = get_size_obj((struct got_object *)item);
157 		break;
158 	case GOT_OBJECT_CACHE_TYPE_TREE:
159 		size = get_size_tree((struct got_tree_object *)item);
160 		break;
161 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
162 		size = get_size_commit((struct got_commit_object *)item);
163 		break;
164 	case GOT_OBJECT_CACHE_TYPE_TAG:
165 		size = get_size_tag((struct got_tag_object *)item);
166 		break;
167 	case GOT_OBJECT_CACHE_TYPE_RAW:
168 		size = get_size_raw((struct got_raw_object *)item);
169 		break;
170 	default:
171 		return got_error(GOT_ERR_OBJ_TYPE);
172 	}
173 
174 	if (size > GOT_OBJECT_CACHE_MAX_ELEM_SIZE) {
175 #ifdef GOT_OBJ_CACHE_DEBUG
176 		char *id_str;
177 		if (got_object_id_str(&id_str, id) != NULL)
178 			return got_error_from_errno("got_object_id_str");
179 		fprintf(stderr, "%s: not caching ", getprogname());
180 		switch (cache->type) {
181 		case GOT_OBJECT_CACHE_TYPE_OBJ:
182 			fprintf(stderr, "object");
183 			break;
184 		case GOT_OBJECT_CACHE_TYPE_TREE:
185 			fprintf(stderr, "tree");
186 			break;
187 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
188 			fprintf(stderr, "commit");
189 			break;
190 		case GOT_OBJECT_CACHE_TYPE_TAG:
191 			fprintf(stderr, "tag");
192 			break;
193 		case GOT_OBJECT_CACHE_TYPE_RAW:
194 			fprintf(stderr, "raw");
195 			break;
196 		}
197 		fprintf(stderr, " %s (%zd bytes; %zd MB)\n", id_str, size,
198 		    size/1024/1024);
199 		free(id_str);
200 #endif
201 		cache->cache_toolarge++;
202 		return got_error(GOT_ERR_OBJ_TOO_LARGE);
203 	}
204 
205 	nelem = got_object_idset_num_elements(cache->idset);
206 	if (nelem >= cache->size) {
207 		err = got_object_idset_remove((void **)&ce,
208 		    cache->idset, NULL);
209 		if (err)
210 			return err;
211 		switch (cache->type) {
212 		case GOT_OBJECT_CACHE_TYPE_OBJ:
213 			got_object_close(ce->data.obj);
214 			break;
215 		case GOT_OBJECT_CACHE_TYPE_TREE:
216 			got_object_tree_close(ce->data.tree);
217 			break;
218 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
219 			got_object_commit_close(ce->data.commit);
220 			break;
221 		case GOT_OBJECT_CACHE_TYPE_TAG:
222 			got_object_tag_close(ce->data.tag);
223 			break;
224 		case GOT_OBJECT_CACHE_TYPE_RAW:
225 			got_object_raw_close(ce->data.raw);
226 			break;
227 		}
228 		free(ce);
229 		cache->cache_evict++;
230 	}
231 
232 	ce = malloc(sizeof(*ce));
233 	if (ce == NULL)
234 		return got_error_from_errno("malloc");
235 	memcpy(&ce->id, id, sizeof(ce->id));
236 	switch (cache->type) {
237 	case GOT_OBJECT_CACHE_TYPE_OBJ:
238 		ce->data.obj = (struct got_object *)item;
239 		break;
240 	case GOT_OBJECT_CACHE_TYPE_TREE:
241 		ce->data.tree = (struct got_tree_object *)item;
242 		break;
243 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
244 		ce->data.commit = (struct got_commit_object *)item;
245 		break;
246 	case GOT_OBJECT_CACHE_TYPE_TAG:
247 		ce->data.tag = (struct got_tag_object *)item;
248 		break;
249 	case GOT_OBJECT_CACHE_TYPE_RAW:
250 		ce->data.raw = (struct got_raw_object *)item;
251 		break;
252 	}
253 
254 	err = got_object_idset_add(cache->idset, id, ce);
255 	if (err)
256 		free(ce);
257 	return err;
258 }
259 
260 void *
261 got_object_cache_get(struct got_object_cache *cache, struct got_object_id *id)
262 {
263 	struct got_object_cache_entry *ce;
264 
265 	cache->cache_searches++;
266 	ce = got_object_idset_get(cache->idset, id);
267 	if (ce) {
268 		cache->cache_hit++;
269 		switch (cache->type) {
270 		case GOT_OBJECT_CACHE_TYPE_OBJ:
271 			return ce->data.obj;
272 		case GOT_OBJECT_CACHE_TYPE_TREE:
273 			return ce->data.tree;
274 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
275 			return ce->data.commit;
276 		case GOT_OBJECT_CACHE_TYPE_TAG:
277 			return ce->data.tag;
278 		case GOT_OBJECT_CACHE_TYPE_RAW:
279 			return ce->data.raw;
280 		}
281 	}
282 
283 	cache->cache_miss++;
284 	return NULL;
285 }
286 
287 #ifdef GOT_OBJ_CACHE_DEBUG
288 static void
289 print_cache_stats(struct got_object_cache *cache, const char *name)
290 {
291 	fprintf(stderr, "%s: %s cache: %d elements, %d searches, %d hits, "
292 	    "%d missed, %d evicted, %d too large\n", getprogname(), name,
293 	    got_object_idset_num_elements(cache->idset),
294 	    cache->cache_searches, cache->cache_hit,
295 	    cache->cache_miss, cache->cache_evict, cache->cache_toolarge);
296 }
297 
298 const struct got_error *
299 check_refcount(struct got_object_id *id, void *data, void *arg)
300 {
301 	struct got_object_cache *cache = arg;
302 	struct got_object_cache_entry *ce = data;
303 	struct got_object *obj;
304 	struct got_tree_object *tree;
305 	struct got_commit_object *commit;
306 	struct got_tag_object *tag;
307 	struct got_raw_object *raw;
308 	char *id_str;
309 
310 	if (got_object_id_str(&id_str, id) != NULL)
311 		return NULL;
312 
313 	switch (cache->type) {
314 	case GOT_OBJECT_CACHE_TYPE_OBJ:
315 		obj = ce->data.obj;
316 		if (obj->refcnt == 1)
317 			break;
318 		fprintf(stderr, "object %s has %d unclaimed references\n",
319 		    id_str, obj->refcnt - 1);
320 		break;
321 	case GOT_OBJECT_CACHE_TYPE_TREE:
322 		tree = ce->data.tree;
323 		if (tree->refcnt == 1)
324 			break;
325 		fprintf(stderr, "tree %s has %d unclaimed references\n",
326 		    id_str, tree->refcnt - 1);
327 		break;
328 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
329 		commit = ce->data.commit;
330 		if (commit->refcnt == 1)
331 			break;
332 		fprintf(stderr, "commit %s has %d unclaimed references\n",
333 		    id_str, commit->refcnt - 1);
334 		break;
335 	case GOT_OBJECT_CACHE_TYPE_TAG:
336 		tag = ce->data.tag;
337 		if (tag->refcnt == 1)
338 			break;
339 		fprintf(stderr, "tag %s has %d unclaimed references\n",
340 		    id_str, tag->refcnt - 1);
341 		break;
342 	case GOT_OBJECT_CACHE_TYPE_RAW:
343 		raw = ce->data.raw;
344 		if (raw->refcnt == 1)
345 			break;
346 		fprintf(stderr, "raw %s has %d unclaimed references\n",
347 		    id_str, raw->refcnt - 1);
348 		break;
349 	}
350 	free(id_str);
351 	return NULL;
352 }
353 #endif
354 
355 void
356 got_object_cache_close(struct got_object_cache *cache)
357 {
358 #ifdef GOT_OBJ_CACHE_DEBUG
359 	switch (cache->type) {
360 	case GOT_OBJECT_CACHE_TYPE_OBJ:
361 		print_cache_stats(cache, "object");
362 		break;
363 	case GOT_OBJECT_CACHE_TYPE_TREE:
364 		print_cache_stats(cache, "tree");
365 		break;
366 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
367 		print_cache_stats(cache, "commit");
368 		break;
369 	case GOT_OBJECT_CACHE_TYPE_TAG:
370 		print_cache_stats(cache, "tag");
371 		break;
372 	case GOT_OBJECT_CACHE_TYPE_RAW:
373 		print_cache_stats(cache, "raw");
374 		break;
375 	}
376 
377 	got_object_idset_for_each(cache->idset, check_refcount, cache);
378 #endif
379 
380 	if (cache->idset) {
381 		got_object_idset_free(cache->idset);
382 		cache->idset = NULL;
383 	}
384 	cache->size = 0;
385 }