mariadb/mysys/my_mmap.c
Alexander Nozdrin 514b9b25d2 Backport of revid:ingo.struewing@sun.com-20091223200354-r2uzbdkj2v6yv111
Bug#47633 - assert in ha_myisammrg::info during OPTIMIZE
 
   The server crashed on an attempt to optimize a MERGE table with
   non-existent child table.
 
   mysql_admin_table() relied on the table to be successfully open
   if a table object had been allocated.
 
   Changed code to check return value of the open function before
   calling a handler:: function on it.
2010-06-25 19:32:59 +04:00

88 lines
2.4 KiB
C

/* Copyright (C) 2000-2003 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 */
#include "mysys_priv.h"
#ifdef HAVE_SYS_MMAN_H
/*
system msync() only syncs mmap'ed area to fs cache.
fsync() is required to really sync to disc
*/
int my_msync(int fd, void *addr, size_t len, int flags)
{
msync(addr, len, flags);
return my_sync(fd, MYF(0));
}
#elif defined(_WIN32)
static SECURITY_ATTRIBUTES mmap_security_attributes=
{sizeof(SECURITY_ATTRIBUTES), 0, TRUE};
void *my_mmap(void *addr, size_t len, int prot,
int flags, File fd, my_off_t offset)
{
HANDLE hFileMap;
LPVOID ptr;
HANDLE hFile= (HANDLE)my_get_osfhandle(fd);
DBUG_ENTER("my_mmap");
DBUG_PRINT("mysys", ("map fd: %d", fd));
if (hFile == INVALID_HANDLE_VALUE)
DBUG_RETURN(MAP_FAILED);
hFileMap=CreateFileMapping(hFile, &mmap_security_attributes,
PAGE_READWRITE, 0, (DWORD) len, NULL);
if (hFileMap == 0)
DBUG_RETURN(MAP_FAILED);
ptr=MapViewOfFile(hFileMap,
prot & PROT_WRITE ? FILE_MAP_WRITE : FILE_MAP_READ,
(DWORD)(offset >> 32), (DWORD)offset, len);
/*
MSDN explicitly states that it's possible to close File Mapping Object
even when a view is not unmapped - then the object will be held open
implicitly until unmap, as every view stores internally a handler of
a corresponding File Mapping Object
*/
CloseHandle(hFileMap);
if (ptr)
{
DBUG_PRINT("mysys", ("mapped addr: %p", ptr));
DBUG_RETURN(ptr);
}
DBUG_RETURN(MAP_FAILED);
}
int my_munmap(void *addr, size_t len)
{
DBUG_ENTER("my_munmap");
DBUG_PRINT("mysys", ("unmap addr: %p", addr));
DBUG_RETURN(UnmapViewOfFile(addr) ? 0 : -1);
}
int my_msync(int fd, void *addr, size_t len, int flags)
{
return FlushViewOfFile(addr, len) ? 0 : -1;
}
#else
#warning "no mmap!"
#endif