2 * cachedb/cachedb.h - cache from a database external to the program module
4 * Copyright (c) 2016, NLnet Labs. All rights reserved.
6 * This software is open source.
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39 * This file contains a module that uses an external database to cache
42 #include "util/module.h"
43 struct cachedb_backend;
46 * The global variable environment contents for the cachedb
47 * Shared between threads, this represents long term information.
48 * Like database connections.
51 /** true is cachedb is enabled, the backend is turned on */
54 /** the backend routines */
55 struct cachedb_backend* backend;
57 /** backend specific data here */
62 * Per query state for the cachedb module.
64 struct cachedb_qstate {
69 * Backend call routines
71 struct cachedb_backend {
75 /** Init(env, cachedb_env): false on setup failure */
76 int (*init)(struct module_env*, struct cachedb_env*);
78 /** Deinit - close db for program exit */
79 void (*deinit)(struct module_env*, struct cachedb_env*);
81 /** Lookup (env, cachedb_env, key, result_buffer): true if found */
82 int (*lookup)(struct module_env*, struct cachedb_env*, char*,
83 struct sldns_buffer*);
85 /** Store (env, cachedb_env, key, data, data_len) */
86 void (*store)(struct module_env*, struct cachedb_env*, char*,
87 uint8_t*, size_t, time_t);
90 #define CACHEDB_HASHSIZE 256 /* bit hash */
92 /** Init the cachedb module */
93 int cachedb_init(struct module_env* env, int id);
94 /** Deinit the cachedb module */
95 void cachedb_deinit(struct module_env* env, int id);
96 /** Operate on an event on a query (in qstate). */
97 void cachedb_operate(struct module_qstate* qstate, enum module_ev event,
98 int id, struct outbound_entry* outbound);
99 /** Subordinate query done, inform this super request of its conclusion */
100 void cachedb_inform_super(struct module_qstate* qstate, int id,
101 struct module_qstate* super);
102 /** clear the cachedb query-specific contents out of qstate */
103 void cachedb_clear(struct module_qstate* qstate, int id);
104 /** return memory estimate for cachedb module */
105 size_t cachedb_get_mem(struct module_env* env, int id);
108 * Get the function block with pointers to the cachedb functions
109 * @return the function block for "cachedb".
111 struct module_func_block* cachedb_get_funcblock(void);