/*
* tries to lock the entry (no r/w)
*/
int
monitor_cache_trylock(
Entry *e )
{
monitor_entry_t *mp;
assert( e != NULL );
assert( e->e_private != NULL );
mp = ( monitor_entry_t * )e->e_private;
return ldap_pvt_thread_mutex_trylock( &mp->mp_mutex );
}
static long send_ldap_ber(
Operation *op,
BerElement *ber )
{
Connection *conn = op->o_conn;
ber_len_t bytes;
long ret = 0;
ber_get_option( ber, LBER_OPT_BER_BYTES_TO_WRITE, &bytes );
/* write only one pdu at a time - wait til it's our turn */
ldap_pvt_thread_mutex_lock( &conn->c_write1_mutex );
if (( op->o_abandon && !op->o_cancel ) || !connection_valid( conn ) ||
conn->c_writers < 0 ) {
ldap_pvt_thread_mutex_unlock( &conn->c_write1_mutex );
return 0;
}
conn->c_writers++;
while ( conn->c_writers > 0 && conn->c_writing ) {
ldap_pvt_thread_cond_wait( &conn->c_write1_cv, &conn->c_write1_mutex );
}
/* connection was closed under us */
if ( conn->c_writers < 0 ) {
/* we're the last waiter, let the closer continue */
if ( conn->c_writers == -1 )
ldap_pvt_thread_cond_signal( &conn->c_write1_cv );
conn->c_writers++;
ldap_pvt_thread_mutex_unlock( &conn->c_write1_mutex );
return 0;
}
/* Our turn */
conn->c_writing = 1;
/* write the pdu */
while( 1 ) {
int err;
/* lock the connection */
if ( ldap_pvt_thread_mutex_trylock( &conn->c_mutex )) {
if ( !connection_valid(conn)) {
ret = 0;
break;
}
ldap_pvt_thread_mutex_unlock( &conn->c_write1_mutex );
ldap_pvt_thread_mutex_lock( &conn->c_write1_mutex );
if ( conn->c_writers < 0 ) {
ret = 0;
break;
}
continue;
}
if ( ber_flush2( conn->c_sb, ber, LBER_FLUSH_FREE_NEVER ) == 0 ) {
ldap_pvt_thread_mutex_unlock( &conn->c_mutex );
ret = bytes;
break;
}
err = sock_errno();
/*
* we got an error. if it's ewouldblock, we need to
* wait on the socket being writable. otherwise, figure
* it's a hard error and return.
*/
Debug( LDAP_DEBUG_CONNS, "ber_flush2 failed errno=%d reason=\"%s\"\n",
err, sock_errstr(err), 0 );
if ( err != EWOULDBLOCK && err != EAGAIN ) {
conn->c_writers--;
conn->c_writing = 0;
ldap_pvt_thread_mutex_unlock( &conn->c_write1_mutex );
connection_closing( conn, "connection lost on write" );
ldap_pvt_thread_mutex_unlock( &conn->c_mutex );
return -1;
}
/* wait for socket to be write-ready */
ldap_pvt_thread_mutex_lock( &conn->c_write2_mutex );
conn->c_writewaiter = 1;
slapd_set_write( conn->c_sd, 2 );
ldap_pvt_thread_mutex_unlock( &conn->c_write1_mutex );
ldap_pvt_thread_mutex_unlock( &conn->c_mutex );
ldap_pvt_thread_cond_wait( &conn->c_write2_cv, &conn->c_write2_mutex );
conn->c_writewaiter = 0;
ldap_pvt_thread_mutex_unlock( &conn->c_write2_mutex );
ldap_pvt_thread_mutex_lock( &conn->c_write1_mutex );
if ( conn->c_writers < 0 ) {
ret = 0;
break;
}
}
conn->c_writing = 0;
if ( conn->c_writers < 0 ) {
conn->c_writers++;
if ( !conn->c_writers )
ldap_pvt_thread_cond_signal( &conn->c_write1_cv );
} else {
conn->c_writers--;
ldap_pvt_thread_cond_signal( &conn->c_write1_cv );
}
ldap_pvt_thread_mutex_unlock( &conn->c_write1_mutex );
return ret;
}
