mariadb/vio/vio.c
Vladislav Vaintroub e080080711 Bug#47571: idle named pipe connection is unkillable
Bug#31621: Windows server hanging during shutdown using named pipes 
           and idle connection
            
Problem: when idle pipe connection is forcefully closed with KILL
statement or when the server goes down, thread that is closing connection
would hang infinitely in CloseHandle(). The reason for the hang is that 
named pipe operations are performed synchronously. In this mode all IOs
on pipe are serialized, that is CloseHandle() will not abort ReadFile() 
in another thread, but wait for ReadFile() to complete.
            
The fix implements asynchrnous mode for named pipes, where operation of file
are not synchronized. Read/Write operation would fire an async IO and wait for
either IO completion or timeout.
            
Note, that with this patch timeouts are properly handled for named pipes.
      
Post-review: Win32 timeout code has been fixed for named pipes and shared
memory. We do not store pointer to NET in vio structure, only the read and 
write timeouts.


include/violite.h:
  Add pipe_overlapped to Vio structure for async IO for named pipes.
sql-common/client.c:
  Use asynchronous pipe IO.
sql/mysqld.cc:
  Use asynchronous pipe IO.
vio/vio.c:
  -Refactor timeouts for win32 protocols: shared memory and named pipes.
  Store read/write timeout in VIO structure, instead of storing pointer
  to NET. New function vio_win32_timeout called indirectly via 
  vio_timeout changes these values.
vio/vio_priv.h:
  Remove vio_ignore_timeout.
  Add vio_win32_timeout to be used for named pipes and shared memory.
vio/viosocket.c:
  Use async IO for named pipes.
  After issuing IO, wait for either IO completion, pipe_close_event
  or timeout.
          
  Refactor timeouts for named pipe and shared memory.
2009-11-02 23:19:58 +01:00

257 lines
7.6 KiB
C

/* Copyright (C) 2000 MySQL AB
This program 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 Software Foundation; version 2 of the License.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
Note that we can't have assertion on file descriptors; The reason for
this is that during mysql shutdown, another thread can close a file
we are working on. In this case we should just return read errors from
the file descriptior.
*/
#include "vio_priv.h"
/*
* Helper to fill most of the Vio* with defaults.
*/
static void vio_init(Vio* vio, enum enum_vio_type type,
my_socket sd, HANDLE hPipe, uint flags)
{
DBUG_ENTER("vio_init");
DBUG_PRINT("enter", ("type: %d sd: %d flags: %d", type, sd, flags));
#ifndef HAVE_VIO_READ_BUFF
flags&= ~VIO_BUFFERED_READ;
#endif
bzero((char*) vio, sizeof(*vio));
vio->type = type;
vio->sd = sd;
vio->hPipe = hPipe;
vio->localhost= flags & VIO_LOCALHOST;
if ((flags & VIO_BUFFERED_READ) &&
!(vio->read_buffer= (char*)my_malloc(VIO_READ_BUFFER_SIZE, MYF(MY_WME))))
flags&= ~VIO_BUFFERED_READ;
#ifdef _WIN32
if (type == VIO_TYPE_NAMEDPIPE)
{
vio->viodelete =vio_delete;
vio->vioerrno =vio_errno;
vio->read =vio_read_pipe;
vio->write =vio_write_pipe;
vio->fastsend =vio_fastsend;
vio->viokeepalive =vio_keepalive;
vio->should_retry =vio_should_retry;
vio->was_interrupted=vio_was_interrupted;
vio->vioclose =vio_close_pipe;
vio->peer_addr =vio_peer_addr;
vio->in_addr =vio_in_addr;
vio->vioblocking =vio_blocking;
vio->is_blocking =vio_is_blocking;
vio->timeout=vio_win32_timeout;
/* Set default timeout */
vio->read_timeout_millis = INFINITE;
vio->write_timeout_millis = INFINITE;
memset(&(vio->pipe_overlapped), 0, sizeof(OVERLAPPED));
vio->pipe_overlapped.hEvent= CreateEvent(NULL, TRUE, FALSE, NULL);
DBUG_VOID_RETURN;
}
#endif
#ifdef HAVE_SMEM
if (type == VIO_TYPE_SHARED_MEMORY)
{
vio->viodelete =vio_delete;
vio->vioerrno =vio_errno;
vio->read =vio_read_shared_memory;
vio->write =vio_write_shared_memory;
vio->fastsend =vio_fastsend;
vio->viokeepalive =vio_keepalive;
vio->should_retry =vio_should_retry;
vio->was_interrupted=vio_was_interrupted;
vio->vioclose =vio_close_shared_memory;
vio->peer_addr =vio_peer_addr;
vio->in_addr =vio_in_addr;
vio->vioblocking =vio_blocking;
vio->is_blocking =vio_is_blocking;
/* Currently, shared memory is on Windows only, hence the below is ok*/
vio->timeout= vio_win32_timeout;
/* Set default timeout */
vio->read_timeout_millis= INFINITE;
vio->write_timeout_millis= INFINITE;
DBUG_VOID_RETURN;
}
#endif
#ifdef HAVE_OPENSSL
if (type == VIO_TYPE_SSL)
{
vio->viodelete =vio_ssl_delete;
vio->vioerrno =vio_errno;
vio->read =vio_ssl_read;
vio->write =vio_ssl_write;
vio->fastsend =vio_fastsend;
vio->viokeepalive =vio_keepalive;
vio->should_retry =vio_should_retry;
vio->was_interrupted=vio_was_interrupted;
vio->vioclose =vio_ssl_close;
vio->peer_addr =vio_peer_addr;
vio->in_addr =vio_in_addr;
vio->vioblocking =vio_ssl_blocking;
vio->is_blocking =vio_is_blocking;
vio->timeout =vio_timeout;
DBUG_VOID_RETURN;
}
#endif /* HAVE_OPENSSL */
{
vio->viodelete =vio_delete;
vio->vioerrno =vio_errno;
vio->read= (flags & VIO_BUFFERED_READ) ? vio_read_buff : vio_read;
vio->write =vio_write;
vio->fastsend =vio_fastsend;
vio->viokeepalive =vio_keepalive;
vio->should_retry =vio_should_retry;
vio->was_interrupted=vio_was_interrupted;
vio->vioclose =vio_close;
vio->peer_addr =vio_peer_addr;
vio->in_addr =vio_in_addr;
vio->vioblocking =vio_blocking;
vio->is_blocking =vio_is_blocking;
vio->timeout =vio_timeout;
}
DBUG_VOID_RETURN;
}
/* Reset initialized VIO to use with another transport type */
void vio_reset(Vio* vio, enum enum_vio_type type,
my_socket sd, HANDLE hPipe, uint flags)
{
my_free(vio->read_buffer, MYF(MY_ALLOW_ZERO_PTR));
vio_init(vio, type, sd, hPipe, flags);
}
/* Open the socket or TCP/IP connection and read the fnctl() status */
Vio *vio_new(my_socket sd, enum enum_vio_type type, uint flags)
{
Vio *vio;
DBUG_ENTER("vio_new");
DBUG_PRINT("enter", ("sd: %d", sd));
if ((vio = (Vio*) my_malloc(sizeof(*vio),MYF(MY_WME))))
{
vio_init(vio, type, sd, 0, flags);
sprintf(vio->desc,
(vio->type == VIO_TYPE_SOCKET ? "socket (%d)" : "TCP/IP (%d)"),
vio->sd);
#if !defined(__WIN__)
#if !defined(NO_FCNTL_NONBLOCK)
/*
We call fcntl() to set the flags and then immediately read them back
to make sure that we and the system are in agreement on the state of
things.
An example of why we need to do this is FreeBSD (and apparently some
other BSD-derived systems, like Mac OS X), where the system sometimes
reports that the socket is set for non-blocking when it really will
block.
*/
fcntl(sd, F_SETFL, 0);
vio->fcntl_mode= fcntl(sd, F_GETFL);
#elif defined(HAVE_SYS_IOCTL_H) /* hpux */
/* Non blocking sockets doesn't work good on HPUX 11.0 */
(void) ioctl(sd,FIOSNBIO,0);
vio->fcntl_mode &= ~O_NONBLOCK;
#endif
#else /* !defined(__WIN__) */
{
/* set to blocking mode by default */
ulong arg=0, r;
r = ioctlsocket(sd,FIONBIO,(void*) &arg);
vio->fcntl_mode &= ~O_NONBLOCK;
}
#endif
}
DBUG_RETURN(vio);
}
#ifdef __WIN__
Vio *vio_new_win32pipe(HANDLE hPipe)
{
Vio *vio;
DBUG_ENTER("vio_new_handle");
if ((vio = (Vio*) my_malloc(sizeof(Vio),MYF(MY_WME))))
{
vio_init(vio, VIO_TYPE_NAMEDPIPE, 0, hPipe, VIO_LOCALHOST);
strmov(vio->desc, "named pipe");
}
DBUG_RETURN(vio);
}
#ifdef HAVE_SMEM
Vio *vio_new_win32shared_memory(HANDLE handle_file_map, HANDLE handle_map,
HANDLE event_server_wrote, HANDLE event_server_read,
HANDLE event_client_wrote, HANDLE event_client_read,
HANDLE event_conn_closed)
{
Vio *vio;
DBUG_ENTER("vio_new_win32shared_memory");
if ((vio = (Vio*) my_malloc(sizeof(Vio),MYF(MY_WME))))
{
vio_init(vio, VIO_TYPE_SHARED_MEMORY, 0, 0, VIO_LOCALHOST);
vio->handle_file_map= handle_file_map;
vio->handle_map= handle_map;
vio->event_server_wrote= event_server_wrote;
vio->event_server_read= event_server_read;
vio->event_client_wrote= event_client_wrote;
vio->event_client_read= event_client_read;
vio->event_conn_closed= event_conn_closed;
vio->shared_memory_remain= 0;
vio->shared_memory_pos= handle_map;
strmov(vio->desc, "shared memory");
}
DBUG_RETURN(vio);
}
#endif
#endif
void vio_delete(Vio* vio)
{
if (!vio)
return; /* It must be safe to delete null pointers. */
if (vio->type != VIO_CLOSED)
vio->vioclose(vio);
my_free((uchar*) vio->read_buffer, MYF(MY_ALLOW_ZERO_PTR));
my_free((uchar*) vio,MYF(0));
}
/*
Cleanup memory allocated by vio or the
components below it when application finish
*/
void vio_end(void)
{
#ifdef HAVE_YASSL
yaSSL_CleanUp();
#endif
}