1 /* This file is part of Pazpar2.
2 Copyright (C) 2006-2013 Index Data
4 Pazpar2 is free software; you can redistribute it and/or modify it under
5 the terms of the GNU General Public License as published by the Free
6 Software Foundation; either version 2, or (at your option) any later
9 Pazpar2 is distributed in the hope that it will be useful, but WITHOUT ANY
10 WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 /** \file connection.c
21 \brief Z39.50 connection (low-level client)
42 #include <yaz/comstack.h>
43 #include <yaz/tcpip.h>
44 #include "connection.h"
50 /* connection counting (1) , disable connection counting (0) */
52 static YAZ_MUTEX g_mutex = 0;
53 static int no_connections = 0;
54 static int total_no_connections = 0;
56 static int connection_use(int delta)
60 yaz_mutex_create(&g_mutex);
61 yaz_mutex_enter(g_mutex);
62 no_connections += delta;
63 result = no_connections;
65 total_no_connections += delta;
66 yaz_mutex_leave(g_mutex);
69 yaz_log(YLOG_LOG, "%s connections=%d", delta > 0 ? "INC" : "DEC",
74 int connections_count(void)
76 return connection_use(0);
81 #define connection_use(x)
82 #define connections_count(x) 0
83 #define connections_count_total(x) 0
87 /** \brief Represents a physical, reusable connection to a remote Z39.50 host
93 struct client *client;
100 int operation_timeout;
102 struct connection *next; // next for same host or next in free list
105 static int connection_connect(struct connection *con, iochan_man_t iochan_man);
107 static int connection_is_idle(struct connection *co)
109 ZOOM_connection link = co->link;
112 if (co->state != Conn_Open || !link)
115 if (!ZOOM_connection_is_idle(link))
117 event = ZOOM_connection_peek_event(link);
118 if (event == ZOOM_EVENT_NONE)
124 ZOOM_connection connection_get_link(struct connection *co)
129 static void remove_connection_from_host(struct connection *con)
131 struct connection **conp = &con->host->connections;
137 *conp = (*conp)->next;
140 conp = &(*conp)->next;
142 yaz_cond_broadcast(con->host->cond_ready);
145 // Close connection and recycle structure
146 static void connection_destroy(struct connection *co)
150 ZOOM_connection_destroy(co->link);
151 iochan_destroy(co->iochan);
153 yaz_log(YLOG_DEBUG, "%p Connection destroy %s", co, co->host->url);
157 client_disconnect(co->client);
165 // Creates a new connection for client, associated with the host of
167 static struct connection *connection_create(struct client *cl,
169 int operation_timeout,
171 iochan_man_t iochan_man)
173 struct connection *co;
175 co = xmalloc(sizeof(*co));
180 client_set_connection(cl, co);
182 co->state = Conn_Closed;
183 co->operation_timeout = operation_timeout;
184 co->session_timeout = session_timeout;
187 connection_connect(co, iochan_man);
189 yaz_mutex_enter(host->mutex);
190 co->next = co->host->connections;
191 co->host->connections = co;
192 yaz_mutex_leave(host->mutex);
198 static void non_block_events_unlocked(struct connection *co)
201 IOCHAN iochan = co->iochan;
202 ZOOM_connection link = co->link;
205 struct client *cl = co->client;
207 int r = ZOOM_event_nonblock(1, &link);
212 ev = ZOOM_connection_last_event(link);
215 yaz_log(YLOG_DEBUG, "%p Connection ZOOM_EVENT_%s", co, ZOOM_get_event_str(ev));
219 case ZOOM_EVENT_TIMEOUT:
223 const char *error, *addinfo;
225 if ((err = ZOOM_connection_error(link, &error, &addinfo)))
227 yaz_log(YLOG_LOG, "Error %s from %s",
228 error, client_get_id(cl));
229 client_set_diagnostic(cl, err, error, addinfo);
230 client_set_state(cl, Client_Error);
234 iochan_settimeout(iochan, co->session_timeout);
235 client_set_state(cl, Client_Idle);
237 yaz_cond_broadcast(co->host->cond_ready);
240 case ZOOM_EVENT_SEND_DATA:
242 case ZOOM_EVENT_RECV_DATA:
244 case ZOOM_EVENT_UNKNOWN:
246 case ZOOM_EVENT_SEND_APDU:
247 client_set_state(co->client, Client_Working);
248 iochan_settimeout(iochan, co->operation_timeout);
250 case ZOOM_EVENT_RECV_APDU:
252 case ZOOM_EVENT_CONNECT:
253 yaz_log(YLOG_LOG, "Connected to %s", client_get_id(cl));
254 co->state = Conn_Open;
256 case ZOOM_EVENT_RECV_SEARCH:
257 client_search_response(cl);
259 case ZOOM_EVENT_RECV_RECORD:
260 client_record_response(cl, &got_records);
263 yaz_log(YLOG_LOG, "Unhandled event (%d) from %s",
264 ev, client_get_id(cl));
270 struct client *cl = co->client;
273 client_check_preferred_watch(cl);
274 client_got_records(cl);
279 static void non_block_events(struct client *cl, struct connection *co)
281 session_enter_rw(client_get_session(cl), "non_block_events");
282 non_block_events_unlocked(co);
283 session_leave_rw(client_get_session(cl), "non_block_events");
286 void connection_continue(struct connection *co)
288 int r = ZOOM_connection_exec_task(co->link);
291 non_block_events_unlocked(co);
295 iochan_setflags(co->iochan, ZOOM_connection_get_mask(co->link));
296 iochan_setfd(co->iochan, ZOOM_connection_get_socket(co->link));
300 static void connection_handler(IOCHAN iochan, int event)
302 struct connection *co = iochan_getdata(iochan);
304 struct host *host = co->host;
306 yaz_mutex_enter(host->mutex);
310 /* no client associated with it.. We are probably getting
311 a closed connection from the target.. Or, perhaps, an unexpected
312 package.. We will just close the connection */
313 yaz_log(YLOG_LOG, "timeout connection %p event=%d", co, event);
314 remove_connection_from_host(co);
315 yaz_mutex_leave(host->mutex);
316 connection_destroy(co);
318 else if (event & EVENT_TIMEOUT)
320 ZOOM_connection_fire_event_timeout(co->link);
322 non_block_events(cl, co);
324 remove_connection_from_host(co);
325 yaz_mutex_leave(host->mutex);
326 connection_destroy(co);
330 yaz_mutex_leave(host->mutex);
332 non_block_events(cl, co);
334 ZOOM_connection_fire_event_socket(co->link, event);
336 non_block_events(cl, co);
340 iochan_setflags(iochan, ZOOM_connection_get_mask(co->link));
341 iochan_setfd(iochan, ZOOM_connection_get_socket(co->link));
347 // Disassociate connection from client
348 static void connection_release(struct connection *co)
350 struct client *cl = co->client;
354 client_set_connection(cl, 0);
358 void connect_resolver_host(struct host *host, iochan_man_t iochan_man)
360 struct connection *con;
363 yaz_mutex_enter(host->mutex);
364 con = host->connections;
367 if (con->state == Conn_Closed)
369 if (!host->ipport) /* unresolved */
371 remove_connection_from_host(con);
372 yaz_mutex_leave(host->mutex);
373 connection_destroy(con);
375 /* start all over .. at some point it will be NULL */
377 else if (!con->client)
379 remove_connection_from_host(con);
380 yaz_mutex_leave(host->mutex);
381 connection_destroy(con);
382 /* start all over .. at some point it will be NULL */
387 yaz_mutex_leave(host->mutex);
388 connection_connect(con, iochan_man);
389 client_start_search(con->client);
395 yaz_log(YLOG_LOG, "connect_resolver_host: state=%d", con->state);
399 yaz_mutex_leave(host->mutex);
402 static struct host *connection_get_host(struct connection *con)
407 static int connection_connect(struct connection *con, iochan_man_t iochan_man)
409 struct host *host = connection_get_host(con);
410 ZOOM_options zoptions = ZOOM_options_create();
414 const char *sru_version = 0;
416 struct session_database *sdb = client_get_database(con->client);
417 const char *apdulog = session_setting_oneval(sdb, PZ_APDULOG);
421 ZOOM_options_set(zoptions, "async", "1");
422 ZOOM_options_set(zoptions, "implementationName", PACKAGE_NAME);
423 ZOOM_options_set(zoptions, "implementationVersion", VERSION);
425 if ((charset = session_setting_oneval(sdb, PZ_NEGOTIATION_CHARSET)))
426 ZOOM_options_set(zoptions, "charset", charset);
428 assert(host->ipport);
431 yaz_log(YLOG_LOG, "proxy=%s", host->ipport);
432 ZOOM_options_set(zoptions, "proxy", host->ipport);
436 assert(host->tproxy);
437 yaz_log(YLOG_LOG, "tproxy=%s", host->ipport);
438 ZOOM_options_set(zoptions, "tproxy", host->ipport);
441 if (apdulog && *apdulog)
442 ZOOM_options_set(zoptions, "apdulog", apdulog);
444 if ((auth = session_setting_oneval(sdb, PZ_AUTHENTICATION)))
445 ZOOM_options_set(zoptions, "user", auth);
446 if ((sru = session_setting_oneval(sdb, PZ_SRU)) && *sru)
447 ZOOM_options_set(zoptions, "sru", sru);
448 if ((sru_version = session_setting_oneval(sdb, PZ_SRU_VERSION))
450 ZOOM_options_set(zoptions, "sru_version", sru_version);
451 if (!(con->link = ZOOM_connection_create(zoptions)))
453 yaz_log(YLOG_FATAL|YLOG_ERRNO, "Failed to create ZOOM Connection");
454 ZOOM_options_destroy(zoptions);
458 if (sru && *sru && !strstr(host->url, "://"))
460 WRBUF w = wrbuf_alloc();
461 wrbuf_puts(w, "http://");
462 wrbuf_puts(w, host->url);
463 ZOOM_connection_connect(con->link, wrbuf_cstr(w), 0);
468 ZOOM_connection_connect(con->link, host->url, 0);
470 con->iochan = iochan_create(-1, connection_handler, 0, "connection_socket");
471 con->state = Conn_Connecting;
472 iochan_settimeout(con->iochan, con->operation_timeout);
473 iochan_setdata(con->iochan, con);
474 iochan_add(iochan_man, con->iochan);
476 client_set_state(con->client, Client_Connecting);
477 ZOOM_options_destroy(zoptions);
481 // Ensure that client has a connection associated
482 int client_prep_connection(struct client *cl,
483 int operation_timeout, int session_timeout,
484 iochan_man_t iochan_man,
485 const struct timeval *abstime)
487 struct connection *co;
488 struct session_database *sdb = client_get_database(cl);
489 const char *zproxy = session_setting_oneval(sdb, PZ_ZPROXY);
490 const char *url = session_setting_oneval(sdb, PZ_URL);
491 const char *sru = session_setting_oneval(sdb, PZ_SRU);
492 struct host *host = 0;
493 int default_port = *sru ? 80 : 210;
495 if (zproxy && zproxy[0] == '\0')
499 url = sdb->database->id;
501 host = find_host(client_get_session(cl)->service->server->database_hosts,
502 url, zproxy, default_port, iochan_man);
504 yaz_log(YLOG_DEBUG, "client_prep_connection: target=%s url=%s",
505 client_get_id(cl), url);
509 co = client_get_connection(cl);
514 if (co->host == host && client_get_state(cl) == Client_Idle)
519 connection_release(co);
524 int max_connections = 0;
525 int reuse_connections = 1;
526 const char *v = session_setting_oneval(client_get_database(cl),
529 max_connections = atoi(v);
531 v = session_setting_oneval(client_get_database(cl),
532 PZ_REUSE_CONNECTIONS);
534 reuse_connections = atoi(v);
536 // See if someone else has an idle connection
537 // We should look at timestamps here to select the longest-idle connection
538 yaz_mutex_enter(host->mutex);
541 int num_connections = 0;
542 for (co = host->connections; co; co = co->next)
544 if (reuse_connections)
546 for (co = host->connections; co; co = co->next)
548 if (connection_is_idle(co) &&
549 (!co->client || client_get_state(co->client) == Client_Idle) &&
550 !strcmp(ZOOM_connection_option_get(co->link, "user"),
551 session_setting_oneval(client_get_database(cl),
554 if (zproxy == 0 && co->zproxy == 0)
556 if (zproxy && co->zproxy && !strcmp(zproxy, co->zproxy))
562 yaz_log(YLOG_LOG, "num_connections = %d (reusing)", num_connections);
566 if (max_connections <= 0 || num_connections < max_connections)
568 yaz_log(YLOG_LOG, "num_connections = %d (new); max = %d",
569 num_connections, max_connections);
572 yaz_log(YLOG_LOG, "num_connections = %d (waiting) max = %d",
573 num_connections, max_connections);
574 if (yaz_cond_wait(host->cond_ready, host->mutex, abstime))
576 yaz_log(YLOG_LOG, "out of connections %s", client_get_id(cl));
577 client_set_state(cl, Client_Error);
578 yaz_mutex_leave(host->mutex);
584 yaz_log(YLOG_LOG, "%p Connection reuse. state: %d", co, co->state);
585 connection_release(co);
586 client_set_connection(cl, co);
588 /* ensure that connection is only assigned to this client
589 by marking the client non Idle */
590 client_set_state(cl, Client_Working);
591 yaz_mutex_leave(host->mutex);
592 co->operation_timeout = operation_timeout;
593 co->session_timeout = session_timeout;
594 /* tells ZOOM to reconnect if necessary. Disabled becuase
595 the ZOOM_connection_connect flushes the task queue */
596 ZOOM_connection_connect(co->link, 0, 0);
600 yaz_mutex_leave(host->mutex);
601 co = connection_create(cl, host, operation_timeout, session_timeout,
616 * c-file-style: "Stroustrup"
617 * indent-tabs-mode: nil
619 * vim: shiftwidth=4 tabstop=8 expandtab