Happy new year
[pazpar2-moved-to-github.git] / src / connection.c
index e1cf29e..e0b809d 100644 (file)
@@ -1,5 +1,5 @@
 /* This file is part of Pazpar2.
-   Copyright (C) 2006-2008 Index Data
+   Copyright (C) 2006-2011 Index Data
 
 Pazpar2 is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free
@@ -34,31 +34,37 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
-#if HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
-#endif
-#ifdef WIN32
-#include <winsock.h>
-typedef int socklen_t;
-#endif
-#if HAVE_NETDB_H
-#include <netdb.h>
-#endif
 
 #include <signal.h>
-#include <ctype.h>
 #include <assert.h>
 
 #include <yaz/log.h>
 #include <yaz/comstack.h>
 #include <yaz/tcpip.h>
 #include "connection.h"
-#include "eventl.h"
-#include "pazpar2.h"
+#include "session.h"
 #include "host.h"
 #include "client.h"
 #include "settings.h"
-#include "parameters.h"
+
+/* connection counting (1) , disable connection counting (0) */
+#if 0
+static YAZ_MUTEX g_mutex = 0;
+static int no_connections = 0;
+
+static void connection_use(int delta)
+{
+    if (!g_mutex)
+        yaz_mutex_create(&g_mutex);
+    yaz_mutex_enter(g_mutex);
+    no_connections += delta;
+    yaz_mutex_leave(g_mutex);
+    yaz_log(YLOG_LOG, "%s connections=%d", delta > 0 ? "INC" : "DEC",
+            no_connections);
+}
+#else
+#define connection_use(x)
+#endif
 
 
 /** \brief Represents a physical, reusable  connection to a remote Z39.50 host
@@ -66,23 +72,21 @@ typedef int socklen_t;
 struct connection {
     IOCHAN iochan;
     ZOOM_connection link;
-    ZOOM_resultset resultset;
     struct host *host;
     struct client *client;
-    char *ibuf;
-    int ibufsize;
     char *zproxy;
     enum {
         Conn_Resolving,
         Conn_Connecting,
-        Conn_Open
+        Conn_Open,
+        Conn_Dead
     } state;
+    int operation_timeout;
+    int session_timeout;
     struct connection *next; // next for same host or next in free list
 };
 
-static struct connection *connection_freelist = 0;
-
-static int connection_connect(struct connection *con);
+static int connection_connect(struct connection *con, iochan_man_t iochan_man);
 
 static int connection_is_idle(struct connection *co)
 {
@@ -92,9 +96,10 @@ static int connection_is_idle(struct connection *co)
     if (co->state != Conn_Open || !link)
         return 0;
 
+    if (!ZOOM_connection_is_idle(link))
+        return 0;
     event = ZOOM_connection_peek_event(link);
-    if (event == ZOOM_EVENT_NONE ||
-                event == ZOOM_EVENT_END)
+    if (event == ZOOM_EVENT_NONE)
         return 1;
     else
         return 0;
@@ -105,18 +110,6 @@ ZOOM_connection connection_get_link(struct connection *co)
     return co->link;
 }
 
-ZOOM_resultset connection_get_resultset(struct connection *co)
-{
-    return co->resultset;
-}
-
-void connection_set_resultset(struct connection *co, ZOOM_resultset rs)
-{
-    if (co->resultset)
-        ZOOM_resultset_destroy(co->resultset);
-    co->resultset = rs;
-}
-
 static void remove_connection_from_host(struct connection *con)
 {
     struct connection **conp = &con->host->connections;
@@ -126,195 +119,264 @@ static void remove_connection_from_host(struct connection *con)
         if (*conp == con)
         {
             *conp = (*conp)->next;
-            return;
+            break;
         }
         conp = &(*conp)->next;
     }
-    assert(*conp == 0);
-}
-
-void connection_continue(struct connection *co)
-{
-    yaz_log(YLOG_LOG, "connection_continue");
-    iochan_setevent(co->iochan, EVENT_OUTPUT);
+    yaz_cond_broadcast(con->host->cond_ready);
 }
 
 // Close connection and recycle structure
-void connection_destroy(struct connection *co)
+static void connection_destroy(struct connection *co)
 {
     if (co->link)
     {
         ZOOM_connection_destroy(co->link);
         iochan_destroy(co->iochan);
     }
-    if (co->resultset)
-        ZOOM_resultset_destroy(co->resultset);
-
-    yaz_log(YLOG_DEBUG, "Connection destroy %s", co->host->hostport);
+    yaz_log(YLOG_DEBUG, "%p Connection destroy %s", co, co->host->hostport);
 
-    remove_connection_from_host(co);
     if (co->client)
     {
         client_disconnect(co->client);
     }
+
     xfree(co->zproxy);
-    co->zproxy = 0;
-    co->next = connection_freelist;
-    connection_freelist = co;
+    xfree(co);
+    connection_use(-1);
 }
 
 // Creates a new connection for client, associated with the host of 
 // client's database
-static struct connection *connection_create(struct client *cl)
+static struct connection *connection_create(struct client *cl,
+                                            int operation_timeout,
+                                            int session_timeout,
+                                            iochan_man_t iochan_man)
 {
-    struct connection *new;
+    struct connection *co;
     struct host *host = client_get_host(cl);
 
-    if ((new = connection_freelist))
-        connection_freelist = new->next;
-    else
+    co = xmalloc(sizeof(*co));
+    co->host = host;
+
+    co->client = cl;
+    co->zproxy = 0;
+    client_set_connection(cl, co);
+    co->link = 0;
+    co->state = Conn_Resolving;
+    co->operation_timeout = operation_timeout;
+    co->session_timeout = session_timeout;
+    if (host->ipport)
+        connection_connect(co, iochan_man);
+
+    yaz_mutex_enter(host->mutex);
+    co->next = co->host->connections;
+    co->host->connections = co;
+    yaz_mutex_leave(host->mutex);
+
+    connection_use(1);
+    return co;
+}
+
+static void non_block_events(struct connection *co)
+{
+    int got_records = 0;
+    IOCHAN iochan = co->iochan;
+    ZOOM_connection link = co->link;
+    while (1)
     {
-        new = xmalloc(sizeof (struct connection));
-        new->ibuf = 0;
-        new->ibufsize = 0;
+        struct client *cl = co->client;
+        int ev;
+        int r = ZOOM_event_nonblock(1, &link);
+        if (!r)
+            break;
+        if (!cl)
+            continue;
+        ev = ZOOM_connection_last_event(link);
+        
+#if 1
+        yaz_log(YLOG_DEBUG, "%p Connection ZOOM_EVENT_%s", co, ZOOM_get_event_str(ev));
+#endif
+        switch (ev) 
+        {
+        case ZOOM_EVENT_END:
+            {
+                const char *error, *addinfo;
+                int err;
+                if ((err = ZOOM_connection_error(link, &error, &addinfo)))
+                {
+                    yaz_log(YLOG_LOG, "Error %s from %s",
+                            error, client_get_url(cl));
+                    client_set_diagnostic(cl, err);
+                    client_set_state(cl, Client_Error);
+                }
+                else
+                {
+                    iochan_settimeout(iochan, co->session_timeout);
+                    client_set_state(cl, Client_Idle);
+                }
+                yaz_cond_broadcast(co->host->cond_ready);
+            }
+            break;
+        case ZOOM_EVENT_SEND_DATA:
+            break;
+        case ZOOM_EVENT_RECV_DATA:
+            break;
+        case ZOOM_EVENT_UNKNOWN:
+            break;
+        case ZOOM_EVENT_SEND_APDU:
+            client_set_state(co->client, Client_Working);
+            iochan_settimeout(iochan, co->operation_timeout);
+            break;
+        case ZOOM_EVENT_RECV_APDU:
+            break;
+        case ZOOM_EVENT_CONNECT:
+            yaz_log(YLOG_LOG, "Connected to %s", client_get_url(cl));
+            co->state = Conn_Open;
+            break;
+        case ZOOM_EVENT_RECV_SEARCH:
+            client_search_response(cl);
+            break;
+        case ZOOM_EVENT_RECV_RECORD:
+            client_record_response(cl);
+            got_records = 1;
+            break;
+        default:
+            yaz_log(YLOG_LOG, "Unhandled event (%d) from %s",
+                    ev, client_get_url(cl));
+        }
+    }
+    if (got_records)
+    {
+        struct client *cl = co->client;
+        if (cl)
+        {
+            client_check_preferred_watch(cl);
+            client_got_records(cl);
+        }
     }
-    new->host = host;
-    new->next = new->host->connections;
-    new->host->connections = new;
-    new->client = cl;
-    new->zproxy = 0;
-    client_set_connection(cl, new);
-    new->link = 0;
-    new->resultset = 0;
-    new->state = Conn_Resolving;
-    if (host->ipport)
-        connection_connect(new);
-    return new;
 }
 
-static void connection_handler(IOCHAN i, int event)
+void connection_continue(struct connection *co)
 {
-    struct connection *co = iochan_getdata(i);
-    struct client *cl = co->client;
-    struct session *se = 0;
+    int r = ZOOM_connection_exec_task(co->link);
+    if (!r)
+        yaz_log(YLOG_WARN, "No task was executed for connection");
+    iochan_setflags(co->iochan, ZOOM_connection_get_mask(co->link));
+    iochan_setfd(co->iochan, ZOOM_connection_get_socket(co->link));
+}
 
-    if (cl)
-        se = client_get_session(cl);
-    else
+static void connection_handler(IOCHAN iochan, int event)
+{
+    struct connection *co = iochan_getdata(iochan);
+    struct client *cl;
+    struct host *host = co->host;
+
+    yaz_mutex_enter(host->mutex);
+    cl = co->client;
+    if (!cl) 
     {
+        /* no client associated with it.. We are probably getting
+           a closed connection from the target.. Or, perhaps, an unexpected
+           package.. We will just close the connection */
+        yaz_log(YLOG_LOG, "timeout connection %p event=%d", co, event);
+        remove_connection_from_host(co);
+        yaz_mutex_leave(host->mutex);
         connection_destroy(co);
-        return;
     }
-
-    if (event & EVENT_TIMEOUT)
+    else if (event & EVENT_TIMEOUT)
     {
         if (co->state == Conn_Connecting)
         {
-            yaz_log(YLOG_WARN,  "connect timeout %s", client_get_url(cl));
-            client_fatal(cl);
+            yaz_log(YLOG_WARN, "%p connect timeout %s", co, client_get_url(cl));
+
+            client_set_state(cl, Client_Error);
+            remove_connection_from_host(co);
+            yaz_mutex_leave(host->mutex);
+            connection_destroy(co);
         }
         else
         {
-            yaz_log(YLOG_LOG,  "idle timeout %s", client_get_url(cl));
+            yaz_log(YLOG_LOG,  "%p Connection idle timeout %s", co, client_get_url(cl));
+            remove_connection_from_host(co);
+            yaz_mutex_leave(host->mutex);
             connection_destroy(co);
         }
-        return;
     }
     else
     {
-        ZOOM_connection link = co->link;
+        yaz_mutex_leave(host->mutex);
 
-        if (ZOOM_event(1, &link))
+        client_lock(cl);
+        non_block_events(co);
+
+        ZOOM_connection_fire_event_socket(co->link, event);
+        
+        non_block_events(co);
+        client_unlock(cl);
+
+        if (co->link)
         {
-            do
-            {
-                int event = ZOOM_connection_last_event(link);
-                switch (event) 
-                {
-                case ZOOM_EVENT_END:
-                    client_set_state(co->client, Client_Idle);
-                    break;
-                case ZOOM_EVENT_SEND_DATA:
-                    break;
-                case ZOOM_EVENT_RECV_DATA:
-                    break;
-                case ZOOM_EVENT_UNKNOWN:
-                    break;
-                case ZOOM_EVENT_SEND_APDU:
-                    client_set_state(co->client, Client_Working);
-                    break;
-                case ZOOM_EVENT_RECV_APDU:
-                    break;
-                case ZOOM_EVENT_CONNECT:
-                    yaz_log(YLOG_LOG, "Connected to %s", client_get_url(cl));
-                    co->state = Conn_Open;
-                    client_set_state(co->client, Client_Connected);
-                    iochan_settimeout(i, global_parameters.z3950_session_timeout);
-                    break;
-                case ZOOM_EVENT_RECV_SEARCH:
-                    yaz_log(YLOG_LOG, "Search response from %s", client_get_url(cl));
-                    client_search_response(cl);
-                    break;
-                case ZOOM_EVENT_RECV_RECORD:
-                    yaz_log(YLOG_LOG, "Record from %s", client_get_url(cl));
-                    client_record_response(cl);
-                    break;
-                default:
-                    yaz_log(YLOG_LOG, "Unhandled event (%d) from %s",
-                            event, client_get_url(cl));
-                }
-            }
-            while (ZOOM_event_nonblock(1, &link));
+            iochan_setflags(iochan, ZOOM_connection_get_mask(co->link));
+            iochan_setfd(iochan, ZOOM_connection_get_socket(co->link));
         }
     }
 }
 
 
 // Disassociate connection from client
-void connection_release(struct connection *co)
+static void connection_release(struct connection *co)
 {
     struct client *cl = co->client;
 
-    yaz_log(YLOG_DEBUG, "Connection release %s", co->host->hostport);
     if (!cl)
         return;
     client_set_connection(cl, 0);
     co->client = 0;
 }
 
-void connect_resolver_host(struct host *host)
+void connect_resolver_host(struct host *host, iochan_man_t iochan_man)
 {
-    struct connection *con = host->connections;
+    struct connection *con;
+
+start:
+    yaz_mutex_enter(host->mutex);
+    con = host->connections;
     while (con)
     {
         if (con->state == Conn_Resolving)
         {
             if (!host->ipport) /* unresolved */
             {
+                remove_connection_from_host(con);
+                yaz_mutex_leave(host->mutex);
                 connection_destroy(con);
+                goto start;
                 /* start all over .. at some point it will be NULL */
-                con = host->connections;
-                continue;
             }
             else if (!con->client)
             {
+                remove_connection_from_host(con);
+                yaz_mutex_leave(host->mutex);
                 connection_destroy(con);
                 /* start all over .. at some point it will be NULL */
-                con = host->connections;
-                continue;
+                goto start;
             }
             else
             {
-                connection_connect(con);
+                yaz_mutex_leave(host->mutex);
+                connection_connect(con, iochan_man);
                 client_start_search(con->client);
+                goto start;
             }
         }
         else
         {
             yaz_log(YLOG_LOG, "connect_resolver_host: state=%d", con->state);
+            con = con->next;
         }
-        con = con->next;
     }
+    yaz_mutex_leave(host->mutex);
 }
 
 static struct host *connection_get_host(struct connection *con)
@@ -322,37 +384,15 @@ static struct host *connection_get_host(struct connection *con)
     return con->host;
 }
 
-// Callback for use by event loop
-// We do this because ZOOM connections don't always have (the same) sockets
-static int socketfun(IOCHAN c)
-{
-    struct connection *co = iochan_getdata(c);
-    if (!co->link)
-        return -1;
-    return ZOOM_connection_get_socket(co->link);
-}
-
-// Because ZOOM always knows what events it is interested in; we may not
-static int maskfun(IOCHAN c)
-{
-    struct connection *co = iochan_getdata(c);
-    if (!co->link)
-        return 0;
-
-    // This is cheating a little, and assuming that eventl mask IDs are always
-    // the same as ZOOM-C's.
-    return ZOOM_connection_get_mask(co->link);
-}
-
-static int connection_connect(struct connection *con)
+static int connection_connect(struct connection *con, iochan_man_t iochan_man)
 {
     ZOOM_connection link = 0;
     struct host *host = connection_get_host(con);
     ZOOM_options zoptions = ZOOM_options_create();
     const char *auth;
+    const char *charset;
     const char *sru;
     const char *sru_version = 0;
-    char ipport[512] = "";
 
     struct session_database *sdb = client_get_database(con->client);
     const char *zproxy = session_setting_oneval(sdb, PZ_ZPROXY);
@@ -362,10 +402,12 @@ static int connection_connect(struct connection *con)
     assert(con);
 
     ZOOM_options_set(zoptions, "async", "1");
-    ZOOM_options_set(zoptions, "implementationName",
-            global_parameters.implementationName);
-    ZOOM_options_set(zoptions, "implementationVersion",
-            global_parameters.implementationVersion);
+    ZOOM_options_set(zoptions, "implementationName", PACKAGE_NAME);
+    ZOOM_options_set(zoptions, "implementationVersion", VERSION);
+       
+    if ((charset = session_setting_oneval(sdb, PZ_NEGOTIATION_CHARSET)))
+        ZOOM_options_set(zoptions, "charset", charset);
+    
     if (zproxy && *zproxy)
     {
         con->zproxy = xstrdup(zproxy);
@@ -390,47 +432,37 @@ static int connection_connect(struct connection *con)
     }
 
     if (sru && *sru)
-        strcpy(ipport, "http://");
-    strcat(ipport, host->ipport);
-    /* deal with SRU path here because databaseName option is not read in
-       ZOOM in SRU mode */
-    if (sru && *sru)
     {
-        if (*sdb->database->databases[0])
-        {
-            strcat(ipport, "/");
-            strcat(ipport, sdb->database->databases[0]);
-        }
+        char http_hostport[512];
+        strcpy(http_hostport, "http://");
+        strcat(http_hostport, host->hostport);
+        ZOOM_connection_connect(link, http_hostport, 0);
     }
-    ZOOM_connection_connect(link, ipport, 0);
+    else if (zproxy && *zproxy)
+        ZOOM_connection_connect(link, host->hostport, 0);        
+    else
+        ZOOM_connection_connect(link, host->ipport, 0);
     
     con->link = link;
-    con->iochan = iochan_create(0, connection_handler, 0);
+    con->iochan = iochan_create(-1, connection_handler, 0, "connection_socket");
     con->state = Conn_Connecting;
-    iochan_settimeout(con->iochan, global_parameters.z3950_connect_timeout);
+    iochan_settimeout(con->iochan, con->operation_timeout);
     iochan_setdata(con->iochan, con);
-    iochan_setsocketfun(con->iochan, socketfun);
-    iochan_setmaskfun(con->iochan, maskfun);
-    pazpar2_add_channel(con->iochan);
+    iochan_add(iochan_man, con->iochan);
 
     /* this fragment is bad DRY: from client_prep_connection */
     client_set_state(con->client, Client_Connecting);
     ZOOM_options_destroy(zoptions);
-    // This creates the connection
-    ZOOM_connection_process(link);
     return 0;
 }
 
-const char *connection_get_url(struct connection *co)
-{
-    return client_get_url(co->client);
-}
-
 // Ensure that client has a connection associated
-int client_prep_connection(struct client *cl)
+int client_prep_connection(struct client *cl,
+                           int operation_timeout, int session_timeout,
+                           iochan_man_t iochan_man,
+                           const struct timeval *abstime)
 {
     struct connection *co;
-    struct session *se = client_get_session(cl);
     struct host *host = client_get_host(cl);
     struct session_database *sdb = client_get_database(cl);
     const char *zproxy = session_setting_oneval(sdb, PZ_ZPROXY);
@@ -438,34 +470,94 @@ int client_prep_connection(struct client *cl)
     if (zproxy && zproxy[0] == '\0')
         zproxy = 0;
 
+    if (!host)
+        return 0;
+
     co = client_get_connection(cl);
 
     yaz_log(YLOG_DEBUG, "Client prep %s", client_get_url(cl));
 
     if (!co)
     {
+        int max_connections = 0;
+        int reuse_connections = 1;
+        const char *v = session_setting_oneval(client_get_database(cl),
+                                               PZ_MAX_CONNECTIONS);
+        if (v && *v)
+            max_connections = atoi(v);
+
+        v = session_setting_oneval(client_get_database(cl),
+                PZ_REUSE_CONNECTIONS);
+        if (v && *v)
+            reuse_connections = atoi(v);
+
         // See if someone else has an idle connection
         // We should look at timestamps here to select the longest-idle connection
-        for (co = host->connections; co; co = co->next)
-            if (connection_is_idle(co) &&
-                (!co->client || client_get_session(co->client) != se) &&
-                !strcmp(ZOOM_connection_option_get(co->link, "user"),
-                        session_setting_oneval(client_get_database(cl),
-                                               PZ_AUTHENTICATION)))
-            {
-                if (zproxy == 0 && co->zproxy == 0)
-                    break;
-                if (zproxy && co->zproxy && !strcmp(zproxy, co->zproxy))
+        yaz_mutex_enter(host->mutex);
+        while (1)
+        {
+            int num_connections = 0;
+            for (co = host->connections; co; co = co->next)
+                num_connections++;
+            if (reuse_connections) {
+                for (co = host->connections; co; co = co->next)
+                {
+                    if (connection_is_idle(co) &&
+                        (!co->client || client_get_state(co->client) == Client_Idle) &&
+                        !strcmp(ZOOM_connection_option_get(co->link, "user"),
+                                session_setting_oneval(client_get_database(cl),
+                                                       PZ_AUTHENTICATION)))
+                    {
+                        if (zproxy == 0 && co->zproxy == 0)
+                            break;
+                        if (zproxy && co->zproxy && !strcmp(zproxy, co->zproxy))
+                            break;
+                    }
+                }
+                if (co)
+                {
+                    yaz_log(YLOG_LOG, "num_connections = %d (reusing)", num_connections);
                     break;
+                }
+            }
+            if (max_connections <= 0 || num_connections < max_connections)
+            {
+                yaz_log(YLOG_LOG, "num_connections = %d (new); max = %d",
+                        num_connections, max_connections);
+                break;
             }
+            yaz_log(YLOG_LOG, "num_connections = %d (waiting) max = %d",
+                    num_connections, max_connections);
+            if (yaz_cond_wait(host->cond_ready, host->mutex, abstime))
+            {
+                yaz_log(YLOG_LOG, "out of connections %s", client_get_url(cl));
+                client_set_state(cl, Client_Error);
+                yaz_mutex_leave(host->mutex);
+                return 0;
+            }
+        }
         if (co)
         {
+            yaz_log(YLOG_LOG,  "%p Connection reuse. state: %d", co, co->state);
             connection_release(co);
             client_set_connection(cl, co);
             co->client = cl;
+            /* ensure that connection is only assigned to this client
+               by marking the client non Idle */
+            client_set_state(cl, Client_Working);
+            yaz_mutex_leave(host->mutex);
+            co->operation_timeout = operation_timeout;
+            co->session_timeout = session_timeout;
+            /* tells ZOOM to reconnect if necessary. Disabled becuase
+               the ZOOM_connection_connect flushes the task queue */
+            ZOOM_connection_connect(co->link, 0, 0);
         }
         else
-            co = connection_create(cl);
+        {
+            yaz_mutex_leave(host->mutex);
+            co = connection_create(cl, operation_timeout, session_timeout,
+                                   iochan_man);
+        }
     }
 
     if (co && co->link)
@@ -477,7 +569,9 @@ int client_prep_connection(struct client *cl)
 /*
  * Local variables:
  * c-basic-offset: 4
+ * c-file-style: "Stroustrup"
  * indent-tabs-mode: nil
  * End:
  * vim: shiftwidth=4 tabstop=8 expandtab
  */
+