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 <string.h>
23 #include <sha1.h>
24 #include <zlib.h>
25 
26 #include "got_error.h"
27 #include "got_object.h"
28 
29 #include "got_lib_delta.h"
30 #include "got_lib_inflate.h"
31 #include "got_lib_object.h"
32 #include "got_lib_object_idcache.h"
33 #include "got_lib_object_cache.h"
34 
35 #define GOT_OBJECT_CACHE_SIZE_OBJ	1024
36 #define GOT_OBJECT_CACHE_SIZE_TREE	2048
37 #define GOT_OBJECT_CACHE_SIZE_COMMIT	512
38 
39 const struct got_error *
40 got_object_cache_init(struct got_object_cache *cache,
41     enum got_object_cache_type type)
42 {
43 	size_t size;
44 
45 	switch (type) {
46 	case GOT_OBJECT_CACHE_TYPE_OBJ:
47 		size = GOT_OBJECT_CACHE_SIZE_OBJ;
48 		break;
49 	case GOT_OBJECT_CACHE_TYPE_TREE:
50 		size = GOT_OBJECT_CACHE_SIZE_TREE;
51 		break;
52 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
53 		size = GOT_OBJECT_CACHE_SIZE_COMMIT;
54 		break;
55 	}
56 
57 	cache->idcache = got_object_idcache_alloc(size);
58 	if (cache->idcache == NULL)
59 		return got_error_from_errno();
60 	cache->type = type;
61 	cache->size = size;
62 	return NULL;
63 }
64 
65 const struct got_error *
66 got_object_cache_add(struct got_object_cache *cache, struct got_object_id *id, void *item)
67 {
68 	const struct got_error *err = NULL;
69 	struct got_object_cache_entry *ce;
70 	int nelem;
71 
72 	nelem = got_object_idcache_num_elements(cache->idcache);
73 	if (nelem >= cache->size) {
74 		err = got_object_idcache_remove_least_used((void **)&ce,
75 		    cache->idcache);
76 		if (err)
77 			return err;
78 		switch (cache->type) {
79 		case GOT_OBJECT_CACHE_TYPE_OBJ:
80 			got_object_close(ce->data.obj);
81 			break;
82 		case GOT_OBJECT_CACHE_TYPE_TREE:
83 			got_object_tree_close(ce->data.tree);
84 			break;
85 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
86 			got_object_commit_close(ce->data.commit);
87 			break;
88 		}
89 		free(ce);
90 		cache->cache_evict++;
91 	}
92 
93 	ce = calloc(1, sizeof(*ce));
94 	if (ce == NULL)
95 		return got_error_from_errno();
96 	memcpy(&ce->id, id, sizeof(ce->id));
97 	switch (cache->type) {
98 	case GOT_OBJECT_CACHE_TYPE_OBJ:
99 		ce->data.obj = (struct got_object *)item;
100 		break;
101 	case GOT_OBJECT_CACHE_TYPE_TREE:
102 		ce->data.tree = (struct got_tree_object *)item;
103 		break;
104 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
105 		ce->data.commit = (struct got_commit_object *)item;
106 		break;
107 	}
108 
109 	err = got_object_idcache_add(cache->idcache, id, ce);
110 	if (err) {
111 		if (err->code == GOT_ERR_OBJ_EXISTS) {
112 			free(ce);
113 			err = NULL;
114 		}
115 	}
116 	return err;
117 }
118 
119 void *
120 got_object_cache_get(struct got_object_cache *cache, struct got_object_id *id)
121 {
122 	struct got_object_cache_entry *ce;
123 
124 	cache->cache_searches++;
125 	ce = got_object_idcache_get(cache->idcache, id);
126 	if (ce) {
127 		cache->cache_hit++;
128 		switch (cache->type) {
129 		case GOT_OBJECT_CACHE_TYPE_OBJ:
130 			return ce->data.obj;
131 		case GOT_OBJECT_CACHE_TYPE_TREE:
132 			return ce->data.tree;
133 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
134 			return ce->data.commit;
135 		}
136 	}
137 
138 	cache->cache_miss++;
139 	return NULL;
140 }
141 
142 #ifdef GOT_OBJ_CACHE_DEBUG
143 static void
144 print_cache_stats(struct got_object_cache *cache, const char *name)
145 {
146 	fprintf(stderr, "%s: %s cache: %d elements, %d searches, %d hits, "
147 	    "%d missed, %d evicted\n", getprogname(), name,
148 	    got_object_idcache_num_elements(cache->idcache),
149 	    cache->cache_searches, cache->cache_hit,
150 	    cache->cache_miss, cache->cache_evict);
151 }
152 
153 void check_refcount(struct got_object_id *id, void *data, void *arg)
154 {
155 	struct got_object_cache *cache = arg;
156 	struct got_object_cache_entry *ce = data;
157 	struct got_object *obj;
158 	struct got_tree_object *tree;
159 	struct got_commit_object *commit;
160 	char *id_str;
161 
162 	if (got_object_id_str(&id_str, id) != NULL)
163 		return;
164 
165 	switch (cache->type) {
166 	case GOT_OBJECT_CACHE_TYPE_OBJ:
167 		obj = ce->data.obj;
168 		if (obj->refcnt == 1)
169 			break;
170 		fprintf(stderr, "object %s has %d unclaimed references\n",
171 		    id_str, obj->refcnt - 1);
172 		break;
173 	case GOT_OBJECT_CACHE_TYPE_TREE:
174 		tree = ce->data.tree;
175 		if (tree->refcnt == 1)
176 			break;
177 		fprintf(stderr, "tree %s has %d unclaimed references\n",
178 		    id_str, tree->refcnt - 1);
179 		break;
180 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
181 		commit = ce->data.commit;
182 		if (commit->refcnt == 1)
183 			break;
184 		fprintf(stderr, "commit %s has %d unclaimed references\n",
185 		    id_str, commit->refcnt - 1);
186 		break;
187 	}
188 	free(id_str);
189 }
190 #endif
191 
192 void
193 got_object_cache_close(struct got_object_cache *cache)
194 {
195 #ifdef GOT_OBJ_CACHE_DEBUG
196 	switch (cache->type) {
197 	case GOT_OBJECT_CACHE_TYPE_OBJ:
198 		print_cache_stats(cache, "object");
199 		break;
200 	case GOT_OBJECT_CACHE_TYPE_TREE:
201 		print_cache_stats(cache, "tree");
202 		break;
203 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
204 		print_cache_stats(cache, "commit");
205 		break;
206 	}
207 
208 	got_object_idcache_for_each(cache->idcache, check_refcount, cache);
209 #endif
210 
211 	if (cache->idcache) {
212 		got_object_idcache_free(cache->idcache);
213 		cache->idcache = NULL;
214 	}
215 	cache->size = 0;
216 }