mpv/osdep/mmap-os2.c

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/*
* very simple implementation of mmap() for OS/2
*
* Copyright (c) 2008 KO Myung-Hun (komh@chollian.net)
*
* This file is part of MPlayer.
*
* MPlayer 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; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer 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 MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#define INCL_DOS
#include <os2.h>
#include <stdio.h>
#include <stdlib.h>
#include <io.h>
#include <sys/types.h>
#include "config.h"
#include "mmap.h"
#include "mmap_anon.h"
typedef struct os2_mmap_s
{
void *addr;
size_t len;
int flags;
struct os2_mmap_s *prev;
struct os2_mmap_s *next;
} os2_mmap;
static os2_mmap *m_mmap = NULL;
void *mmap( void *addr, size_t len, int prot, int flags, int fildes, off_t off )
{
os2_mmap *new_mmap;
ULONG fl;
ULONG rc;
void *ret;
if( prot & PROT_WRITE )
{
if( flags & MAP_SHARED )
return MAP_FAILED;
if( !( flags & MAP_PRIVATE ))
return MAP_FAILED;
}
if( flags & MAP_FIXED )
{
ULONG cb;
cb = len;
rc = DosQueryMem( addr, &cb, &fl );
if( rc || ( cb < len ))
return MAP_FAILED;
rc = DosSetMem( addr, len, fPERM );
if( rc )
return MAP_FAILED;
ret = addr;
}
else
{
// Allocate tiled memory compatible with 16-bit selectors
// 'fs_seg' in 'ldt_keeper.c' need this attribute
rc = DosAllocMem( &ret, len, fALLOC );
if( rc )
return MAP_FAILED;
}
new_mmap = malloc( sizeof( os2_mmap ));
new_mmap->addr = ret;
new_mmap->len = len;
new_mmap->flags = flags;
new_mmap->prev = m_mmap;
new_mmap->next = NULL;
if( m_mmap )
m_mmap->next = new_mmap;
m_mmap = new_mmap;
if( !( flags & MAP_ANON ))
{
int pos;
/* Now read in the file */
if(( pos = lseek( fildes, off, SEEK_SET )) == -1)
{
munmap( ret, len );
return MAP_FAILED;
}
read( fildes, ret, len );
lseek( fildes, pos, SEEK_SET ); /* Restore the file pointer */
}
fl = 0;
if( prot & PROT_READ )
fl |= PAG_READ;
if( prot & PROT_WRITE )
fl |= PAG_WRITE;
if( prot & PROT_EXEC )
fl |= PAG_EXECUTE;
if( prot & PROT_NONE )
fl |= PAG_GUARD;
rc = DosSetMem( ret, len, fl );
if( rc )
{
munmap( ret, len );
return MAP_FAILED;
}
return ret;
}
int munmap( void *addr, size_t len )
{
os2_mmap *mm;
for( mm = m_mmap; mm; mm = mm->prev )
{
if( mm->addr == addr )
break;
}
if( mm )
{
if( !( mm->flags & MAP_FIXED ))
DosFreeMem( addr );
if( mm->next )
mm->next->prev = mm->prev;
if( mm->prev )
mm->prev->next = mm->next;
if( m_mmap == mm )
m_mmap = mm->prev;
free( mm );
return 0;
}
return -1;
}
int mprotect( void *addr, size_t len, int prot )
{
os2_mmap *mm;
for( mm = m_mmap; mm; mm = mm->prev )
{
if( mm->addr == addr )
break;
}
if( mm )
{
ULONG fl;
fl = 0;
if( prot & PROT_READ )
fl |= PAG_READ;
if( prot & PROT_WRITE )
fl |= PAG_WRITE;
if( prot & PROT_EXEC )
fl |= PAG_EXECUTE;
if( prot & PROT_NONE )
fl |= PAG_GUARD;
if( DosSetMem( addr, len, fl ) == 0 )
return 0;
}
return -1;
}
void *mmap_anon( void *addr, size_t len, int prot, int flags, off_t off )
{
return mmap( addr, len, prot, flags | MAP_ANON, -1, off );
}