1 /* Copyright 2003-5 The Apache Software Foundation or its licensors, as
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 /* Overview of what this is and does:
18 * http://www.apache.org/~niq/dbd.html
20 * http://apache.webthing.com/database/
25 #include "http_protocol.h"
26 #include "http_config.h"
28 #include "apr_reslist.h"
29 #include "apr_strings.h"
33 extern module AP_MODULE_DECLARE_DATA dbd_module;
35 /************ svr cfg: manage db connection pool ****************/
37 typedef struct dbd_prepared {
40 struct dbd_prepared *next;
42 typedef struct svr_cfg {
46 dbd_prepared *prepared;
48 apr_reslist_t *dbpool;
58 typedef enum { cmd_name, cmd_params, cmd_persist,
59 cmd_min, cmd_keep, cmd_max, cmd_exp
64 for (p = val; *p; ++p) \
66 return "Argument must be numeric!"
67 static const char *dbd_param(cmd_parms *cmd, void *cfg, const char *val)
70 const apr_dbd_driver_t *driver = NULL;
71 svr_cfg *svr = (svr_cfg*) ap_get_module_config
72 (cmd->server->module_config, &dbd_module);
74 switch ((long) cmd->info) {
77 /* loading the driver involves once-only dlloading that is
78 * best done at server startup. This also guarantees that
79 * load_driver won't return an error later.
81 switch (apr_dbd_get_driver(cmd->pool, svr->name, &driver)) {
83 return apr_psprintf(cmd->pool, "DBD: No driver for %s", svr->name);
85 return apr_psprintf(cmd->pool,
86 "DBD: Can't load driver file apr_dbd_%s.so",
88 case APR_ESYMNOTFOUND:
89 return apr_psprintf(cmd->pool,
90 "DBD: Failed to load driver apr_dbd_%s_driver",
99 svr->persist = atoi(val);
104 svr->nmin = atoi(val);
108 svr->nkeep = atoi(val);
112 svr->nmax = atoi(val);
116 svr->exptime = atoi(val);
122 void ap_dbd_prepare(server_rec *s, const char *query, const char *label)
124 svr_cfg *svr = ap_get_module_config(s->module_config, &dbd_module);
125 dbd_prepared *prepared = apr_pcalloc(s->process->pool, sizeof(dbd_prepared));
126 prepared->label = label;
127 prepared->query = query;
128 prepared->next = svr->prepared;
129 svr->prepared = prepared;
131 static const char *dbd_prepare(cmd_parms *cmd, void *cfg, const char *query,
134 ap_dbd_prepare(cmd->server, query, label);
137 static const command_rec dbd_cmds[] = {
138 AP_INIT_TAKE1("DBDriver", dbd_param, (void*)cmd_name, RSRC_CONF,
140 AP_INIT_TAKE1("DBDParams", dbd_param, (void*)cmd_params, RSRC_CONF,
141 "SQL Driver Params"),
142 AP_INIT_TAKE1("DBDPersist", dbd_param, (void*)cmd_persist, RSRC_CONF,
143 "Use persistent connection/pool"),
144 AP_INIT_TAKE2("DBDPrepareSQL", dbd_prepare, NULL, RSRC_CONF,
145 "Prepared SQL statement, label"),
147 AP_INIT_TAKE1("DBDMin", dbd_param, (void*)cmd_min, RSRC_CONF,
148 "Minimum number of connections"),
149 AP_INIT_TAKE1("DBDKeep", dbd_param, (void*)cmd_keep, RSRC_CONF,
150 "Maximum number of sustained connections"),
151 AP_INIT_TAKE1("DBDMax", dbd_param, (void*)cmd_max, RSRC_CONF,
152 "Maximum number of connections"),
153 AP_INIT_TAKE1("DBDExptime", dbd_param, (void*)cmd_exp, RSRC_CONF,
154 "Keepalive time for idle connections"),
158 #define DEFAULT_NMIN 0
159 #define DEFAULT_NMAX 5
160 #define DEFAULT_NKEEP 1
161 #define DEFAULT_EXPTIME 120
162 #define COND_PARAM(x,val) \
163 if (cfg->x == val) { \
164 cfg->x = ((svr_cfg*)base)->x; \
166 #define COND_PARAM0(x) COND_PARAM(x,0)
167 #define COND_PARAM1(x) COND_PARAM(x,-1)
168 static void *dbd_merge(apr_pool_t *pool, void *base, void *add) {
169 svr_cfg *cfg = apr_pmemdup(pool, add, sizeof(svr_cfg));
172 COND_PARAM1(persist);
174 COND_PARAM(nmin, DEFAULT_NMIN);
175 COND_PARAM(nkeep, DEFAULT_NKEEP);
176 COND_PARAM(nmax, DEFAULT_NMAX);
177 COND_PARAM(exptime, DEFAULT_EXPTIME);
184 static void *dbd_cfg(apr_pool_t *p, server_rec *x)
186 svr_cfg *svr = (svr_cfg*) apr_pcalloc(p, sizeof(svr_cfg));
189 svr->nmin = DEFAULT_NMIN;
190 svr->nkeep = DEFAULT_NKEEP;
191 svr->nmax = DEFAULT_NMAX;
192 svr->exptime = DEFAULT_EXPTIME;
196 static apr_status_t dbd_prepared_init(apr_pool_t *pool, svr_cfg *svr,
200 apr_status_t ret = APR_SUCCESS;
201 apr_dbd_prepared_t *stmt = NULL;
202 dbd->prepared = apr_hash_make(pool);
204 for (p = svr->prepared; p; p = p->next) {
205 if (apr_dbd_prepare(dbd->driver, pool, dbd->handle, p->query,
206 p->label, &stmt) == 0) {
207 apr_hash_set(dbd->prepared, p->label, APR_HASH_KEY_STRING, stmt);
215 /************ svr cfg: manage db connection pool ****************/
216 /* an apr_reslist_constructor for SQL connections
217 * Also use this for opening in non-reslist modes, since it gives
218 * us all the error-handling in one place.
220 static apr_status_t dbd_construct(void **db, void *params, apr_pool_t *pool)
222 svr_cfg *svr = (svr_cfg*) params;
223 ap_dbd_t *rec = apr_pcalloc(pool, sizeof(ap_dbd_t));
224 apr_status_t rv = apr_dbd_get_driver(pool, svr->name, &rec->driver);
226 /* Error-checking get_driver isn't necessary now (because it's done at
227 * config-time). But in case that changes in future ...
231 ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, pool,
232 "DBD: driver for %s not available", svr->name);
235 ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, pool,
236 "DBD: can't find driver for %s", svr->name);
238 case APR_ESYMNOTFOUND:
239 ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, pool,
240 "DBD: driver for %s is invalid or corrupted", svr->name);
243 ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, pool,
244 "DBD: mod_dbd not compatible with apr in get_driver");
250 rv = apr_dbd_open(rec->driver, pool, svr->params, &rec->handle);
253 ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, pool,
254 "DBD: Can't connect to %s[%s]", svr->name, svr->params);
257 ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, pool,
258 "DBD: mod_dbd not compatible with apr in open");
264 rv = dbd_prepared_init(pool, svr, rec);
268 static apr_status_t dbd_destruct(void *sql, void *params, apr_pool_t *pool)
271 return apr_dbd_close(rec->driver, rec->handle);
274 static apr_status_t dbd_setup(apr_pool_t *pool, server_rec *s)
276 svr_cfg *svr = ap_get_module_config(s->module_config, &dbd_module);
277 apr_status_t rv = apr_reslist_create(&svr->dbpool, svr->nmin, svr->nkeep,
278 svr->nmax, svr->exptime,
279 dbd_construct, dbd_destruct,
281 if (rv == APR_SUCCESS) {
282 apr_pool_cleanup_register(pool, svr->dbpool,
283 (void*)apr_reslist_destroy,
284 apr_pool_cleanup_null);
287 ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, pool,
288 "DBD Pool: failed to initialise");
296 /* Functions we export for modules to use:
297 - open acquires a connection from the pool (opens one if necessary)
298 - close releases it back in to the pool
300 #define arec ((ap_dbd_t*)rec)
302 ap_dbd_t* ap_dbd_open(apr_pool_t *pool, server_rec *s)
305 svr_cfg *svr = ap_get_module_config(s->module_config, &dbd_module);
306 apr_status_t rv = APR_SUCCESS;
310 /* Return a once-only connection */
311 rv = dbd_construct(&rec, svr, s->process->pool);
312 return (rv == APR_SUCCESS) ? arec : NULL;
316 if (dbd_setup(s->process->pool, s) != APR_SUCCESS) {
320 if (apr_reslist_acquire(svr->dbpool, &rec) != APR_SUCCESS) {
321 ap_log_perror(APLOG_MARK, APLOG_ERR, 0, pool,
322 "Failed to acquire DBD connection from pool!");
325 rv = apr_dbd_check_conn(arec->driver, pool, arec->handle);
326 if ((rv != APR_SUCCESS) && (rv != APR_ENOTIMPL)) {
327 errmsg = apr_dbd_error(arec->driver, arec->handle, rv);
329 errmsg = "(unknown)";
331 ap_log_perror(APLOG_MARK, APLOG_ERR, 0, pool,
332 "DBD[%s] Error: %s", svr->name, errmsg );
333 apr_reslist_invalidate(svr->dbpool, rec);
339 ap_dbd_t* ap_dbd_open(apr_pool_t *pool, server_rec *s)
341 apr_status_t rv = APR_SUCCESS;
344 svr_cfg *svr = ap_get_module_config(s->module_config, &dbd_module);
347 /* Return a once-only connection */
348 rv = dbd_construct(&rec, svr, s->process->pool);
349 return (rv == APR_SUCCESS) ? arec : NULL;
352 /* since we're in nothread-land, we can mess with svr->conn with impunity */
353 /* If we have a persistent connection and it's good, we'll use it */
355 rv = apr_dbd_check_conn(svr->conn->driver, pool, svr->conn->handle);
356 if ((rv != APR_SUCCESS) && (rv != APR_ENOTIMPL)) {
357 errmsg = apr_dbd_error(arec->driver, arec->handle, rv);
359 errmsg = "(unknown)";
361 ap_log_perror(APLOG_MARK, APLOG_ERR, 0, pool,
362 "DBD[%s] Error: %s", svr->name, errmsg);
366 /* We don't have a connection right now, so we'll open one */
368 rv = dbd_construct(&rec, svr, s->process->pool);
369 svr->conn = (rv == APR_SUCCESS) ? arec : NULL;
374 void ap_dbd_close(server_rec *s, ap_dbd_t *sql)
376 svr_cfg *svr = ap_get_module_config(s->module_config, &dbd_module);
378 apr_dbd_close(sql->driver, sql->handle);
382 apr_reslist_release(svr->dbpool, sql);
386 static apr_status_t dbd_close(void *CONN)
388 ap_dbd_t *conn = CONN;
389 return apr_dbd_close(conn->driver, conn->handle);
394 apr_reslist_t *dbpool;
396 static apr_status_t dbd_release(void *REQ)
398 dbd_pool_rec *req = REQ;
399 apr_reslist_release(req->dbpool, req->conn);
402 ap_dbd_t *ap_dbd_acquire(request_rec *r)
405 dbd_pool_rec *req = ap_get_module_config(r->request_config, &dbd_module);
407 req = apr_palloc(r->pool, sizeof(dbd_pool_rec));
408 req->conn = ap_dbd_open(r->pool, r->server);
410 svr = ap_get_module_config(r->server->module_config, &dbd_module);
411 ap_set_module_config(r->request_config, &dbd_module, req);
413 req->dbpool = svr->dbpool;
414 apr_pool_cleanup_register(r->pool, req, dbd_release,
415 apr_pool_cleanup_null);
418 apr_pool_cleanup_register(r->pool, req->conn, dbd_close,
419 apr_pool_cleanup_null);
425 ap_dbd_t *ap_dbd_cacquire(conn_rec *c)
428 dbd_pool_rec *req = ap_get_module_config(c->conn_config, &dbd_module);
430 req = apr_palloc(c->pool, sizeof(dbd_pool_rec));
431 req->conn = ap_dbd_open(c->pool, c->base_server);
433 svr = ap_get_module_config(c->base_server->module_config, &dbd_module);
434 ap_set_module_config(c->conn_config, &dbd_module, req);
436 req->dbpool = svr->dbpool;
437 apr_pool_cleanup_register(c->pool, req, dbd_release,
438 apr_pool_cleanup_null);
441 apr_pool_cleanup_register(c->pool, req->conn, dbd_close,
442 apr_pool_cleanup_null);
449 ap_dbd_t *ap_dbd_acquire(request_rec *r)
452 ap_dbd_t *ret = ap_get_module_config(r->request_config, &dbd_module);
454 svr = ap_get_module_config(r->server->module_config, &dbd_module);
455 ret = ap_dbd_open(r->pool, r->server);
457 ap_set_module_config(r->request_config, &dbd_module, ret);
459 apr_pool_cleanup_register(r->pool, svr->conn, dbd_close,
460 apr_pool_cleanup_null);
462 /* if persist then dbd_open registered cleanup on proc pool */
467 ap_dbd_t *ap_dbd_cacquire(conn_rec *c)
470 ap_dbd_t *ret = ap_get_module_config(c->conn_config, &dbd_module);
472 svr = ap_get_module_config(c->base_server->module_config, &dbd_module);
473 ret = ap_dbd_open(c->pool, c->base_server);
475 ap_set_module_config(c->conn_config, &dbd_module, ret);
477 apr_pool_cleanup_register(c->pool, svr->conn, dbd_close,
478 apr_pool_cleanup_null);
480 /* if persist then dbd_open registered cleanup on proc pool */
487 static void dbd_hooks(apr_pool_t *pool)
490 ap_hook_child_init((void*)dbd_setup, NULL, NULL, APR_HOOK_MIDDLE);
492 APR_REGISTER_OPTIONAL_FN(ap_dbd_open);
493 APR_REGISTER_OPTIONAL_FN(ap_dbd_close);
494 APR_REGISTER_OPTIONAL_FN(ap_dbd_acquire);
495 APR_REGISTER_OPTIONAL_FN(ap_dbd_cacquire);
496 APR_REGISTER_OPTIONAL_FN(ap_dbd_prepare);
500 module AP_MODULE_DECLARE_DATA dbd_module = {
501 STANDARD20_MODULE_STUFF,