Add emulation of non-blocking sockets to the win32 socket/signal layer,

and use this in pq_getbyte_if_available.

It's only a limited implementation which swithes the whole emulation layer
no non-blocking mode, but that's enough as long as non-blocking is only
used during a short period of time, and only one socket is accessed during
this time.
This commit is contained in:
Magnus Hagander 2010-02-16 19:26:02 +00:00
parent 492eaefb90
commit 215cbc90f8
3 changed files with 40 additions and 3 deletions

View File

@ -30,7 +30,7 @@
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/backend/libpq/pqcomm.c,v 1.202 2010/01/15 09:19:02 heikki Exp $
* $PostgreSQL: pgsql/src/backend/libpq/pqcomm.c,v 1.203 2010/02/16 19:26:02 mha Exp $
*
*-------------------------------------------------------------------------
*/
@ -837,9 +837,13 @@ pq_getbyte_if_available(unsigned char *c)
}
/* Temporarily put the socket into non-blocking mode */
#ifdef WIN32
pgwin32_noblock = 1;
#else
if (!pg_set_noblock(MyProcPort->sock))
ereport(ERROR,
(errmsg("couldn't put socket to non-blocking mode: %m")));
#endif
MyProcPort->noblock = true;
PG_TRY();
{
@ -851,16 +855,24 @@ pq_getbyte_if_available(unsigned char *c)
* The rest of the backend code assumes the socket is in blocking
* mode, so treat failure as FATAL.
*/
#ifdef WIN32
pgwin32_noblock = 0;
#else
if (!pg_set_block(MyProcPort->sock))
ereport(FATAL,
(errmsg("couldn't put socket to blocking mode: %m")));
#endif
MyProcPort->noblock = false;
PG_RE_THROW();
}
PG_END_TRY();
#ifdef WIN32
pgwin32_noblock = 0;
#else
if (!pg_set_block(MyProcPort->sock))
ereport(FATAL,
(errmsg("couldn't put socket to blocking mode: %m")));
#endif
MyProcPort->noblock = false;
return r;

View File

@ -6,13 +6,26 @@
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/port/win32/socket.c,v 1.23 2010/01/02 16:57:50 momjian Exp $
* $PostgreSQL: pgsql/src/backend/port/win32/socket.c,v 1.24 2010/02/16 19:26:02 mha Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
/*
* Indicate if pgwin32_recv() should operate in non-blocking mode.
*
* Since the socket emulation layer always sets the actual socket to
* non-blocking mode in order to be able to deliver signals, we must
* specify this in a separate flag if we actually need non-blocking
* operation.
*
* This flag changes the behaviour *globally* for all socket operations,
* so it should only be set for very short periods of time.
*/
int pgwin32_noblock = 0;
#undef socket
#undef accept
#undef connect
@ -310,6 +323,16 @@ pgwin32_recv(SOCKET s, char *buf, int len, int f)
return -1;
}
if (pgwin32_noblock)
{
/*
* No data received, and we are in "emulated non-blocking mode", so return
* indicating thta we'd block if we were to continue.
*/
errno = EWOULDBLOCK;
return -1;
}
/* No error, zero bytes (win2000+) or error+WSAEWOULDBLOCK (<=nt4) */
for (n = 0; n < 5; n++)

View File

@ -1,4 +1,4 @@
/* $PostgreSQL: pgsql/src/include/port/win32.h,v 1.92 2010/02/13 02:34:14 tgl Exp $ */
/* $PostgreSQL: pgsql/src/include/port/win32.h,v 1.93 2010/02/16 19:26:02 mha Exp $ */
#if defined(_MSC_VER) || defined(__BORLANDC__)
#define WIN32_ONLY_COMPILER
@ -283,6 +283,8 @@ int pgwin32_send(SOCKET s, char *buf, int len, int flags);
const char *pgwin32_socket_strerror(int err);
int pgwin32_waitforsinglesocket(SOCKET s, int what, int timeout);
extern int pgwin32_noblock;
/* in backend/port/win32/security.c */
extern int pgwin32_is_admin(void);
extern int pgwin32_is_service(void);