mariadb/mysys/my_quick.c
Vladislav Vaintroub 4171483b53 Backport Fix for Bug#24509 - 2048 file descriptor limit on windows needs increasing.
The patch replaces the use of the POSIX I/O interfaces in mysys on Windows with 
the Win32 API calls (CreateFile, WriteFile, etc). The Windows HANDLE for the open
 file is stored in the my_file_info struct, along with a flag for append mode 
(because the Windows API does not support opening files in append mode in all cases)
The default max open files has been increased to 16384 and can be increased further
by setting --max-open-files=<value> during the server start.

Noteworthy benefit of this patch is that it removes limits from the table_cache size - 
allowing for more simultaneus users
2011-06-12 15:52:07 +02:00

81 lines
2.2 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 */
/* Quicker interface to read & write. Used with my_nosys.h */
#include "mysys_priv.h"
#include "my_nosys.h"
#ifdef _WIN32
extern size_t my_win_read(File Filedes,uchar *Buffer,size_t Count);
#endif
size_t my_quick_read(File Filedes,uchar *Buffer,size_t Count,myf MyFlags)
{
size_t readbytes;
#ifdef _WIN32
readbytes= my_win_read(Filedes, Buffer, Count);
#else
readbytes= read(Filedes, Buffer, Count);
#endif
if(readbytes != Count)
{
#ifndef DBUG_OFF
if ((readbytes == 0 || readbytes == (size_t) -1) && errno == EINTR)
{
DBUG_PRINT("error", ("my_quick_read() was interrupted and returned %d"
". This function does not retry the read!",
(int) readbytes));
}
#endif
my_errno=errno;
return readbytes;
}
return (MyFlags & (MY_NABP | MY_FNABP)) ? 0 : readbytes;
}
size_t my_quick_write(File Filedes, const uchar *Buffer, size_t Count)
{
#ifdef _WIN32
return my_win_write(Filedes, Buffer, Count);
#else
#ifndef DBUG_OFF
size_t writtenbytes;
#endif
if ((
#ifndef DBUG_OFF
writtenbytes =
#endif
(size_t) write(Filedes,Buffer,Count)) != Count)
{
#ifndef DBUG_OFF
if ((writtenbytes == 0 || writtenbytes == (size_t) -1) && errno == EINTR)
{
DBUG_PRINT("error", ("my_quick_write() was interrupted and returned %d"
". This function does not retry the write!",
(int) writtenbytes));
}
#endif
my_errno=errno;
return (size_t) -1;
}
return 0;
#endif
}