Sweden-Number/server/mapping.c

209 lines
5.9 KiB
C

/*
* Server-side file mapping management
*
* Copyright (C) 1999 Alexandre Julliard
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "config.h"
#include "winerror.h"
#include "winnt.h"
#include "winbase.h"
#include "handle.h"
#include "thread.h"
struct mapping
{
struct object obj; /* object header */
int size_high; /* mapping size */
int size_low; /* mapping size */
int protect; /* protection flags */
struct file *file; /* file mapped */
};
static void mapping_dump( struct object *obj, int verbose );
static void mapping_destroy( struct object *obj );
static const struct object_ops mapping_ops =
{
mapping_dump,
no_add_queue,
NULL, /* should never get called */
NULL, /* should never get called */
NULL, /* should never get called */
no_read_fd,
no_write_fd,
no_flush,
no_get_file_info,
mapping_destroy
};
#ifdef __i386__
/* These are always the same on an i386, and it will be faster this way */
# define page_mask 0xfff
# define page_shift 12
# define init_page_size() /* nothing */
#else /* __i386__ */
static int page_shift, page_mask;
static void init_page_size(void)
{
int page_size;
# ifdef HAVE_GETPAGESIZE
page_size = getpagesize();
# else
# ifdef __svr4__
page_size = sysconf(_SC_PAGESIZE);
# else
# error Cannot get the page size on this platform
# endif
# endif
page_mask = page_size - 1;
/* Make sure we have a power of 2 */
assert( !(page_size & page_mask) );
page_shift = 0;
while ((1 << page_shift) != page_size) page_shift++;
}
#endif /* __i386__ */
#define ROUND_ADDR(addr) \
((int)(addr) & ~page_mask)
#define ROUND_SIZE(addr,size) \
(((int)(size) + ((int)(addr) & page_mask) + page_mask) & ~page_mask)
static struct object *create_mapping( int size_high, int size_low, int protect,
int handle, const char *name )
{
struct mapping *mapping;
int access = 0;
if (!page_mask) init_page_size();
if (!(mapping = (struct mapping *)create_named_object( name, &mapping_ops,
sizeof(*mapping) )))
return NULL;
if (GET_ERROR() == ERROR_ALREADY_EXISTS)
return &mapping->obj; /* Nothing else to do */
if (protect & VPROT_READ) access |= GENERIC_READ;
if (protect & VPROT_WRITE) access |= GENERIC_WRITE;
size_low = ROUND_SIZE( 0, size_low );
if (handle != -1)
{
if (!(mapping->file = get_file_obj( current->process, handle, access ))) goto error;
if (!size_high && !size_low)
{
struct get_file_info_reply reply;
struct object *obj = (struct object *)mapping->file;
obj->ops->get_file_info( obj, &reply );
size_high = reply.size_high;
size_low = ROUND_SIZE( 0, reply.size_low );
}
else if (!grow_file( mapping->file, size_high, size_low )) goto error;
}
else /* Anonymous mapping (no associated file) */
{
if (!size_high && !size_low)
{
SET_ERROR( ERROR_INVALID_PARAMETER );
mapping->file = NULL;
goto error;
}
if (!(mapping->file = create_temp_file( access ))) goto error;
if (!grow_file( mapping->file, size_high, size_low )) goto error;
}
mapping->size_high = size_high;
mapping->size_low = size_low;
mapping->protect = protect;
return &mapping->obj;
error:
release_object( mapping );
return NULL;
}
static int get_mapping_info( int handle, struct get_mapping_info_reply *reply )
{
struct mapping *mapping;
int fd;
if (!(mapping = (struct mapping *)get_handle_obj( current->process, handle,
0, &mapping_ops )))
return -1;
reply->size_high = mapping->size_high;
reply->size_low = mapping->size_low;
reply->protect = mapping->protect;
if (mapping->file) fd = file_get_mmap_fd( mapping->file );
else fd = -1;
release_object( mapping );
return fd;
}
static void mapping_dump( struct object *obj, int verbose )
{
struct mapping *mapping = (struct mapping *)obj;
assert( obj->ops == &mapping_ops );
fprintf( stderr, "Mapping size=%08x%08x prot=%08x file=%p name='%s'\n",
mapping->size_high, mapping->size_low, mapping->protect,
mapping->file, get_object_name( &mapping->obj ) );
}
static void mapping_destroy( struct object *obj )
{
struct mapping *mapping = (struct mapping *)obj;
assert( obj->ops == &mapping_ops );
if (mapping->file) release_object( mapping->file );
free( mapping );
}
/* create a file mapping */
DECL_HANDLER(create_mapping)
{
struct object *obj;
struct create_mapping_reply reply = { -1 };
char *name = (char *)data;
if (!len) name = NULL;
else CHECK_STRING( "create_mapping", name, len );
if ((obj = create_mapping( req->size_high, req->size_low,
req->protect, req->handle, name )))
{
int access = FILE_MAP_ALL_ACCESS;
if (!(req->protect & VPROT_WRITE)) access &= ~FILE_MAP_WRITE;
reply.handle = alloc_handle( current->process, obj, access, req->inherit );
release_object( obj );
}
send_reply( current, -1, 1, &reply, sizeof(reply) );
}
/* open a handle to a mapping */
DECL_HANDLER(open_mapping)
{
struct open_mapping_reply reply;
char *name = (char *)data;
if (!len) name = NULL;
else CHECK_STRING( "open_mapping", name, len );
reply.handle = open_object( name, &mapping_ops, req->access, req->inherit );
send_reply( current, -1, 1, &reply, sizeof(reply) );
}
/* get a mapping information */
DECL_HANDLER(get_mapping_info)
{
struct get_mapping_info_reply reply;
int map_fd = get_mapping_info( req->handle, &reply );
send_reply( current, map_fd, 1, &reply, sizeof(reply) );
}