haproxy/include/proto/stream_interface.h
Willy Tarreau cff6411f9a [MAJOR] add a connection error state to the stream_interface
Tracking connection status changes was hard, and some code was
redundant. A new SI_ST_CER state was added to the stream interface
to indicate a past connection error, and an SI_FL_ERR flag was
added to report past I/O error. The stream_sock code does not set
the connection to SI_ST_CLO anymore in case of I/O error, it's
the upper layer which does it. This makes it possible to know
exactly when the file descriptors are allocated.

The new SI_ST_CER state permitted to split tcp_connection_status()
in two parts, one processing SI_ST_CON and the other one SI_ST_CER.
Synchronous connection errors now make use of this last state, hence
eliminating duplicate code.

Some ib<->ob copy paste errors were found and fixed, and all entities
setting SI_ST_CLO also shut the buffers down.

Some of these stream_interface specific functions and structures
have migrated to a new stream_interface.c file.

Some types of errors are still not detected by the buffers. For
instance, let's assume the following scenario in one single pass
of process_session: a connection sits in SI_ST_TAR state during
a retry. At TAR expiration, a new connection attempt is made, the
connection is obtained and srv->cur_sess is increased. Then the
buffer timeout is fires and everything is cleared, the new state
becomes SI_ST_CLO. The cleaning code checks that previous state
was either SI_ST_CON or SI_ST_EST to release the connection. But
that's wrong because last state is still SI_ST_TAR. So the
server's connection count does not get decreased.

This means that prev_state must not be used, and must be replaced
by some transition detection instead of level detection.

The following debugging line was useful to track state changes :

  fprintf(stderr, "%s:%d: cs=%d ss=%d(%d) rqf=0x%08x rpf=0x%08x\n", __FUNCTION__, __LINE__,
          s->si[0].state, s->si[1].state, s->si[1].err_type, s->req->flags, s-> rep->flags);
2008-11-03 06:26:53 +01:00

43 lines
1.3 KiB
C

/*
include/proto/stream_interface.h
This file contains stream_interface function prototypes
Copyright (C) 2000-2008 Willy Tarreau - w@1wt.eu
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation, version 2.1
exclusively.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _PROTO_STREAM_INTERFACE_H
#define _PROTO_STREAM_INTERFACE_H
#include <stdlib.h>
#include <common/config.h>
#include <types/stream_interface.h>
/* main event functions used to move data between sockets and buffers */
void stream_int_check_timeouts(struct stream_interface *si);
void stream_int_report_error(struct stream_interface *si);
#endif /* _PROTO_STREAM_INTERFACE_H */
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/