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 
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <stdint.h>
23 #include <string.h>
24 #include <sha1.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	32
44 #define GOT_OBJECT_CACHE_MAX_ELEM_SIZE	1048576	/* 1 MB */
45 
46 const struct got_error *
47 got_object_cache_init(struct got_object_cache *cache,
48     enum got_object_cache_type type)
49 {
50 	memset(cache, 0, sizeof(*cache));
51 
52 	cache->idset = got_object_idset_alloc();
53 	if (cache->idset == NULL)
54 		return got_error_from_errno("got_object_idset_alloc");
55 
56 	cache->type = type;
57 	switch (type) {
58 	case GOT_OBJECT_CACHE_TYPE_OBJ:
59 		cache->size = GOT_OBJECT_CACHE_SIZE_OBJ;
60 		break;
61 	case GOT_OBJECT_CACHE_TYPE_TREE:
62 		cache->size = GOT_OBJECT_CACHE_SIZE_TREE;
63 		break;
64 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
65 		cache->size = GOT_OBJECT_CACHE_SIZE_COMMIT;
66 		break;
67 	case GOT_OBJECT_CACHE_TYPE_TAG:
68 		cache->size = GOT_OBJECT_CACHE_SIZE_TAG;
69 		break;
70 	}
71 	return NULL;
72 }
73 
74 size_t
75 get_size_obj(struct got_object *obj)
76 {
77 	size_t size = sizeof(*obj);
78 	struct got_delta *delta;
79 
80 	if (obj->flags & GOT_OBJ_FLAG_PACKED)
81 		size += strlen(obj->path_packfile);
82 
83 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0)
84 		return size;
85 
86 	SIMPLEQ_FOREACH(delta, &obj->deltas.entries, entry) {
87 		if (SIZE_MAX - (sizeof(*delta) + delta->delta_len) < size)
88 			return SIZE_MAX;
89 		size += sizeof(*delta) + delta->delta_len;
90 	}
91 
92 	return size;
93 }
94 
95 size_t
96 get_size_tree(struct got_tree_object *tree)
97 {
98 	size_t size = sizeof(*tree);
99 	struct got_tree_entry *te;
100 
101 	SIMPLEQ_FOREACH(te, &tree->entries.head, entry) {
102 		size += sizeof(*te);
103 		size += strlen(te->name);
104 		size += sizeof(*te->id);
105 	}
106 
107 	return size;
108 }
109 
110 size_t
111 get_size_commit(struct got_commit_object *commit)
112 {
113 	size_t size = sizeof(*commit);
114 	struct got_object_qid *qid;
115 
116 	size += sizeof(*commit->tree_id);
117 	size += strlen(commit->author);
118 	size += strlen(commit->committer);
119 	size += strlen(commit->logmsg);
120 
121 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry)
122 		size += sizeof(*qid) + sizeof(*qid->id);
123 
124 	return size;
125 }
126 
127 size_t
128 get_size_tag(struct got_tag_object *tag)
129 {
130 	size_t size = sizeof(*tag);
131 
132 	size += strlen(tag->tag);
133 	size += strlen(tag->tagger);
134 	size += strlen(tag->tagmsg);
135 
136 	return size;
137 }
138 
139 const struct got_error *
140 got_object_cache_add(struct got_object_cache *cache, struct got_object_id *id, void *item)
141 {
142 	const struct got_error *err = NULL;
143 	struct got_object_cache_entry *ce;
144 	int nelem;
145 	size_t size;
146 
147 	switch (cache->type) {
148 	case GOT_OBJECT_CACHE_TYPE_OBJ:
149 		size = get_size_obj((struct got_object *)item);
150 		break;
151 	case GOT_OBJECT_CACHE_TYPE_TREE:
152 		size = get_size_tree((struct got_tree_object *)item);
153 		break;
154 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
155 		size = get_size_commit((struct got_commit_object *)item);
156 		break;
157 	case GOT_OBJECT_CACHE_TYPE_TAG:
158 		size = get_size_tag((struct got_tag_object *)item);
159 		break;
160 	}
161 
162 	if (size > GOT_OBJECT_CACHE_MAX_ELEM_SIZE) {
163 #ifdef GOT_OBJ_CACHE_DEBUG
164 		char *id_str;
165 		if (got_object_id_str(&id_str, id) != NULL)
166 			return got_error_from_errno("got_object_id_str");
167 		fprintf(stderr, "%s: not caching ", getprogname());
168 		switch (cache->type) {
169 		case GOT_OBJECT_CACHE_TYPE_OBJ:
170 			fprintf(stderr, "object");
171 			break;
172 		case GOT_OBJECT_CACHE_TYPE_TREE:
173 			fprintf(stderr, "tree");
174 			break;
175 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
176 			fprintf(stderr, "commit");
177 			break;
178 		case GOT_OBJECT_CACHE_TYPE_TAG:
179 			fprintf(stderr, "tag");
180 			break;
181 		}
182 		fprintf(stderr, " %s (%zd bytes; %zd MB)\n", id_str, size,
183 		    size/1024/1024);
184 		free(id_str);
185 #endif
186 		cache->cache_toolarge++;
187 		return NULL;
188 	}
189 
190 	nelem = got_object_idset_num_elements(cache->idset);
191 	if (nelem >= cache->size) {
192 		err = got_object_idset_remove((void **)&ce,
193 		    cache->idset, NULL);
194 		if (err)
195 			return err;
196 		switch (cache->type) {
197 		case GOT_OBJECT_CACHE_TYPE_OBJ:
198 			got_object_close(ce->data.obj);
199 			break;
200 		case GOT_OBJECT_CACHE_TYPE_TREE:
201 			got_object_tree_close(ce->data.tree);
202 			break;
203 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
204 			got_object_commit_close(ce->data.commit);
205 			break;
206 		case GOT_OBJECT_CACHE_TYPE_TAG:
207 			got_object_tag_close(ce->data.tag);
208 			break;
209 		}
210 		free(ce);
211 		cache->cache_evict++;
212 	}
213 
214 	ce = malloc(sizeof(*ce));
215 	if (ce == NULL)
216 		return got_error_from_errno("malloc");
217 	memcpy(&ce->id, id, sizeof(ce->id));
218 	switch (cache->type) {
219 	case GOT_OBJECT_CACHE_TYPE_OBJ:
220 		ce->data.obj = (struct got_object *)item;
221 		break;
222 	case GOT_OBJECT_CACHE_TYPE_TREE:
223 		ce->data.tree = (struct got_tree_object *)item;
224 		break;
225 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
226 		ce->data.commit = (struct got_commit_object *)item;
227 		break;
228 	case GOT_OBJECT_CACHE_TYPE_TAG:
229 		ce->data.tag = (struct got_tag_object *)item;
230 		break;
231 	}
232 
233 	err = got_object_idset_add(cache->idset, id, ce);
234 	if (err) {
235 		if (err->code == GOT_ERR_OBJ_EXISTS) {
236 			free(ce);
237 			err = NULL;
238 		}
239 	}
240 	return err;
241 }
242 
243 void *
244 got_object_cache_get(struct got_object_cache *cache, struct got_object_id *id)
245 {
246 	struct got_object_cache_entry *ce;
247 
248 	cache->cache_searches++;
249 	ce = got_object_idset_get(cache->idset, id);
250 	if (ce) {
251 		cache->cache_hit++;
252 		switch (cache->type) {
253 		case GOT_OBJECT_CACHE_TYPE_OBJ:
254 			return ce->data.obj;
255 		case GOT_OBJECT_CACHE_TYPE_TREE:
256 			return ce->data.tree;
257 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
258 			return ce->data.commit;
259 		case GOT_OBJECT_CACHE_TYPE_TAG:
260 			return ce->data.tag;
261 		}
262 	}
263 
264 	cache->cache_miss++;
265 	return NULL;
266 }
267 
268 #ifdef GOT_OBJ_CACHE_DEBUG
269 static void
270 print_cache_stats(struct got_object_cache *cache, const char *name)
271 {
272 	fprintf(stderr, "%s: %s cache: %d elements, %d searches, %d hits, "
273 	    "%d missed, %d evicted, %d too large\n", getprogname(), name,
274 	    got_object_idset_num_elements(cache->idset),
275 	    cache->cache_searches, cache->cache_hit,
276 	    cache->cache_miss, cache->cache_evict, cache->cache_toolarge);
277 }
278 
279 const struct got_error *
280 check_refcount(struct got_object_id *id, void *data, void *arg)
281 {
282 	struct got_object_cache *cache = arg;
283 	struct got_object_cache_entry *ce = data;
284 	struct got_object *obj;
285 	struct got_tree_object *tree;
286 	struct got_commit_object *commit;
287 	struct got_tag_object *tag;
288 	char *id_str;
289 
290 	if (got_object_id_str(&id_str, id) != NULL)
291 		return NULL;
292 
293 	switch (cache->type) {
294 	case GOT_OBJECT_CACHE_TYPE_OBJ:
295 		obj = ce->data.obj;
296 		if (obj->refcnt == 1)
297 			break;
298 		fprintf(stderr, "object %s has %d unclaimed references\n",
299 		    id_str, obj->refcnt - 1);
300 		break;
301 	case GOT_OBJECT_CACHE_TYPE_TREE:
302 		tree = ce->data.tree;
303 		if (tree->refcnt == 1)
304 			break;
305 		fprintf(stderr, "tree %s has %d unclaimed references\n",
306 		    id_str, tree->refcnt - 1);
307 		break;
308 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
309 		commit = ce->data.commit;
310 		if (commit->refcnt == 1)
311 			break;
312 		fprintf(stderr, "commit %s has %d unclaimed references\n",
313 		    id_str, commit->refcnt - 1);
314 		break;
315 	case GOT_OBJECT_CACHE_TYPE_TAG:
316 		tag = ce->data.tag;
317 		if (tag->refcnt == 1)
318 			break;
319 		fprintf(stderr, "tag %s has %d unclaimed references\n",
320 		    id_str, tag->refcnt - 1);
321 		break;
322 	}
323 	free(id_str);
324 	return NULL;
325 }
326 #endif
327 
328 void
329 got_object_cache_close(struct got_object_cache *cache)
330 {
331 #ifdef GOT_OBJ_CACHE_DEBUG
332 	switch (cache->type) {
333 	case GOT_OBJECT_CACHE_TYPE_OBJ:
334 		print_cache_stats(cache, "object");
335 		break;
336 	case GOT_OBJECT_CACHE_TYPE_TREE:
337 		print_cache_stats(cache, "tree");
338 		break;
339 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
340 		print_cache_stats(cache, "commit");
341 		break;
342 	case GOT_OBJECT_CACHE_TYPE_TAG:
343 		print_cache_stats(cache, "tag");
344 		break;
345 	}
346 
347 	got_object_idset_for_each(cache->idset, check_refcount, cache);
348 #endif
349 
350 	if (cache->idset) {
351 		got_object_idset_free(cache->idset);
352 		cache->idset = NULL;
353 	}
354 	cache->size = 0;
355 }