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	256
36 #define GOT_OBJECT_CACHE_SIZE_TREE	256
37 #define GOT_OBJECT_CACHE_SIZE_COMMIT	64
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 	memset(cache, 0, sizeof(*cache));
46 
47 	switch (type) {
48 	case GOT_OBJECT_CACHE_TYPE_OBJ:
49 		size = GOT_OBJECT_CACHE_SIZE_OBJ;
50 		break;
51 	case GOT_OBJECT_CACHE_TYPE_TREE:
52 		size = GOT_OBJECT_CACHE_SIZE_TREE;
53 		break;
54 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
55 		size = GOT_OBJECT_CACHE_SIZE_COMMIT;
56 		break;
57 	}
58 
59 	cache->idcache = got_object_idcache_alloc(size);
60 	if (cache->idcache == NULL)
61 		return got_error_from_errno();
62 	cache->type = type;
63 	cache->size = size;
64 	return NULL;
65 }
66 
67 const struct got_error *
68 got_object_cache_add(struct got_object_cache *cache, struct got_object_id *id, void *item)
69 {
70 	const struct got_error *err = NULL;
71 	struct got_object_cache_entry *ce;
72 	int nelem;
73 
74 	nelem = got_object_idcache_num_elements(cache->idcache);
75 	if (nelem >= cache->size) {
76 		err = got_object_idcache_remove_least_used((void **)&ce,
77 		    cache->idcache);
78 		if (err)
79 			return err;
80 		switch (cache->type) {
81 		case GOT_OBJECT_CACHE_TYPE_OBJ:
82 			got_object_close(ce->data.obj);
83 			break;
84 		case GOT_OBJECT_CACHE_TYPE_TREE:
85 			got_object_tree_close(ce->data.tree);
86 			break;
87 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
88 			got_object_commit_close(ce->data.commit);
89 			break;
90 		}
91 		free(ce);
92 		cache->cache_evict++;
93 	}
94 
95 	ce = calloc(1, sizeof(*ce));
96 	if (ce == NULL)
97 		return got_error_from_errno();
98 	memcpy(&ce->id, id, sizeof(ce->id));
99 	switch (cache->type) {
100 	case GOT_OBJECT_CACHE_TYPE_OBJ:
101 		ce->data.obj = (struct got_object *)item;
102 		break;
103 	case GOT_OBJECT_CACHE_TYPE_TREE:
104 		ce->data.tree = (struct got_tree_object *)item;
105 		break;
106 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
107 		ce->data.commit = (struct got_commit_object *)item;
108 		break;
109 	}
110 
111 	err = got_object_idcache_add(cache->idcache, id, ce);
112 	if (err) {
113 		if (err->code == GOT_ERR_OBJ_EXISTS) {
114 			free(ce);
115 			err = NULL;
116 		}
117 	}
118 	return err;
119 }
120 
121 void *
122 got_object_cache_get(struct got_object_cache *cache, struct got_object_id *id)
123 {
124 	struct got_object_cache_entry *ce;
125 
126 	cache->cache_searches++;
127 	ce = got_object_idcache_get(cache->idcache, id);
128 	if (ce) {
129 		cache->cache_hit++;
130 		switch (cache->type) {
131 		case GOT_OBJECT_CACHE_TYPE_OBJ:
132 			return ce->data.obj;
133 		case GOT_OBJECT_CACHE_TYPE_TREE:
134 			return ce->data.tree;
135 		case GOT_OBJECT_CACHE_TYPE_COMMIT:
136 			return ce->data.commit;
137 		}
138 	}
139 
140 	cache->cache_miss++;
141 	return NULL;
142 }
143 
144 #ifdef GOT_OBJ_CACHE_DEBUG
145 static void
146 print_cache_stats(struct got_object_cache *cache, const char *name)
147 {
148 	fprintf(stderr, "%s: %s cache: %d elements, %d searches, %d hits, "
149 	    "%d missed, %d evicted\n", getprogname(), name,
150 	    got_object_idcache_num_elements(cache->idcache),
151 	    cache->cache_searches, cache->cache_hit,
152 	    cache->cache_miss, cache->cache_evict);
153 }
154 
155 void check_refcount(struct got_object_id *id, void *data, void *arg)
156 {
157 	struct got_object_cache *cache = arg;
158 	struct got_object_cache_entry *ce = data;
159 	struct got_object *obj;
160 	struct got_tree_object *tree;
161 	struct got_commit_object *commit;
162 	char *id_str;
163 
164 	if (got_object_id_str(&id_str, id) != NULL)
165 		return;
166 
167 	switch (cache->type) {
168 	case GOT_OBJECT_CACHE_TYPE_OBJ:
169 		obj = ce->data.obj;
170 		if (obj->refcnt == 1)
171 			break;
172 		fprintf(stderr, "object %s has %d unclaimed references\n",
173 		    id_str, obj->refcnt - 1);
174 		break;
175 	case GOT_OBJECT_CACHE_TYPE_TREE:
176 		tree = ce->data.tree;
177 		if (tree->refcnt == 1)
178 			break;
179 		fprintf(stderr, "tree %s has %d unclaimed references\n",
180 		    id_str, tree->refcnt - 1);
181 		break;
182 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
183 		commit = ce->data.commit;
184 		if (commit->refcnt == 1)
185 			break;
186 		fprintf(stderr, "commit %s has %d unclaimed references\n",
187 		    id_str, commit->refcnt - 1);
188 		break;
189 	}
190 	free(id_str);
191 }
192 #endif
193 
194 void
195 got_object_cache_close(struct got_object_cache *cache)
196 {
197 #ifdef GOT_OBJ_CACHE_DEBUG
198 	switch (cache->type) {
199 	case GOT_OBJECT_CACHE_TYPE_OBJ:
200 		print_cache_stats(cache, "object");
201 		break;
202 	case GOT_OBJECT_CACHE_TYPE_TREE:
203 		print_cache_stats(cache, "tree");
204 		break;
205 	case GOT_OBJECT_CACHE_TYPE_COMMIT:
206 		print_cache_stats(cache, "commit");
207 		break;
208 	}
209 
210 	got_object_idcache_for_each(cache->idcache, check_refcount, cache);
211 #endif
212 
213 	if (cache->idcache) {
214 		got_object_idcache_free(cache->idcache);
215 		cache->idcache = NULL;
216 	}
217 	cache->size = 0;
218 }