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 		return NULL;
164 
165 	nelem = got_object_idset_num_elements(cache->idset);
166 	if (nelem >= cache->size) {
167 		err = got_object_idset_remove((void **)&ce,
168 		    cache->idset, NULL);
169 		if (err)
170 			return err;
171 		switch (cache->type) {
172 		case GOT_OBJECT_CACHE_TYPE_OBJ:
173 			got_object_close(ce->data.obj);
174 			break;
175 		case GOT_OBJECT_CACHE_TYPE_TREE:
176 			got_object_tree_close(ce->data.tree);
177 			break;
178 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
179 			got_object_commit_close(ce->data.commit);
180 			break;
181 		case GOT_OBJECT_CACHE_TYPE_TAG:
182 			got_object_tag_close(ce->data.tag);
183 			break;
184 		}
185 		free(ce);
186 		cache->cache_evict++;
187 	}
188 
189 	ce = malloc(sizeof(*ce));
190 	if (ce == NULL)
191 		return got_error_from_errno("malloc");
192 	memcpy(&ce->id, id, sizeof(ce->id));
193 	switch (cache->type) {
194 	case GOT_OBJECT_CACHE_TYPE_OBJ:
195 		ce->data.obj = (struct got_object *)item;
196 		break;
197 	case GOT_OBJECT_CACHE_TYPE_TREE:
198 		ce->data.tree = (struct got_tree_object *)item;
199 		break;
200 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
201 		ce->data.commit = (struct got_commit_object *)item;
202 		break;
203 	case GOT_OBJECT_CACHE_TYPE_TAG:
204 		ce->data.tag = (struct got_tag_object *)item;
205 		break;
206 	}
207 
208 	err = got_object_idset_add(cache->idset, id, ce);
209 	if (err) {
210 		if (err->code == GOT_ERR_OBJ_EXISTS) {
211 			free(ce);
212 			err = NULL;
213 		}
214 	}
215 	return err;
216 }
217 
218 void *
219 got_object_cache_get(struct got_object_cache *cache, struct got_object_id *id)
220 {
221 	struct got_object_cache_entry *ce;
222 
223 	cache->cache_searches++;
224 	ce = got_object_idset_get(cache->idset, id);
225 	if (ce) {
226 		cache->cache_hit++;
227 		switch (cache->type) {
228 		case GOT_OBJECT_CACHE_TYPE_OBJ:
229 			return ce->data.obj;
230 		case GOT_OBJECT_CACHE_TYPE_TREE:
231 			return ce->data.tree;
232 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
233 			return ce->data.commit;
234 		case GOT_OBJECT_CACHE_TYPE_TAG:
235 			return ce->data.tag;
236 		}
237 	}
238 
239 	cache->cache_miss++;
240 	return NULL;
241 }
242 
243 #ifdef GOT_OBJ_CACHE_DEBUG
244 static void
245 print_cache_stats(struct got_object_cache *cache, const char *name)
246 {
247 	fprintf(stderr, "%s: %s cache: %d elements, %d searches, %d hits, "
248 	    "%d missed, %d evicted\n", getprogname(), name,
249 	    got_object_idset_num_elements(cache->idset),
250 	    cache->cache_searches, cache->cache_hit,
251 	    cache->cache_miss, cache->cache_evict);
252 }
253 
254 const struct got_error *
255 check_refcount(struct got_object_id *id, void *data, void *arg)
256 {
257 	struct got_object_cache *cache = arg;
258 	struct got_object_cache_entry *ce = data;
259 	struct got_object *obj;
260 	struct got_tree_object *tree;
261 	struct got_commit_object *commit;
262 	struct got_tag_object *tag;
263 	char *id_str;
264 
265 	if (got_object_id_str(&id_str, id) != NULL)
266 		return NULL;
267 
268 	switch (cache->type) {
269 	case GOT_OBJECT_CACHE_TYPE_OBJ:
270 		obj = ce->data.obj;
271 		if (obj->refcnt == 1)
272 			break;
273 		fprintf(stderr, "object %s has %d unclaimed references\n",
274 		    id_str, obj->refcnt - 1);
275 		break;
276 	case GOT_OBJECT_CACHE_TYPE_TREE:
277 		tree = ce->data.tree;
278 		if (tree->refcnt == 1)
279 			break;
280 		fprintf(stderr, "tree %s has %d unclaimed references\n",
281 		    id_str, tree->refcnt - 1);
282 		break;
283 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
284 		commit = ce->data.commit;
285 		if (commit->refcnt == 1)
286 			break;
287 		fprintf(stderr, "commit %s has %d unclaimed references\n",
288 		    id_str, commit->refcnt - 1);
289 		break;
290 	case GOT_OBJECT_CACHE_TYPE_TAG:
291 		tag = ce->data.tag;
292 		if (tag->refcnt == 1)
293 			break;
294 		fprintf(stderr, "tag %s has %d unclaimed references\n",
295 		    id_str, tag->refcnt - 1);
296 		break;
297 	}
298 	free(id_str);
299 	return NULL;
300 }
301 #endif
302 
303 void
304 got_object_cache_close(struct got_object_cache *cache)
305 {
306 #ifdef GOT_OBJ_CACHE_DEBUG
307 	switch (cache->type) {
308 	case GOT_OBJECT_CACHE_TYPE_OBJ:
309 		print_cache_stats(cache, "object");
310 		break;
311 	case GOT_OBJECT_CACHE_TYPE_TREE:
312 		print_cache_stats(cache, "tree");
313 		break;
314 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
315 		print_cache_stats(cache, "commit");
316 		break;
317 	case GOT_OBJECT_CACHE_TYPE_TAG:
318 		print_cache_stats(cache, "tag");
319 		break;
320 	}
321 
322 	got_object_idset_for_each(cache->idset, check_refcount, cache);
323 #endif
324 
325 	if (cache->idset) {
326 		got_object_idset_free(cache->idset);
327 		cache->idset = NULL;
328 	}
329 	cache->size = 0;
330 }