EMILE/libmap/map_read.c

35 lines
647 B
C

/*
*
* (c) 2004-2007 Laurent Vivier <Laurent@lvivier.info>
*
*/
#include <sys/types.h>
#include <unistd.h>
#include "libmap.h"
int map_read(map_t *map, int part)
{
off_t offset;
int ret;
int blocksize = map->device->get_blocksize(map->device);
if (map->current == part)
return part;
if (part > read_long((u_int32_t*)&map->partition.MapBlkCnt))
return -1;
offset = part * sizeof(struct Partition) + sizeof(struct DriverDescriptor);
ret = map->device->read_sector(map->device->data, offset / blocksize, &map->partition,
sizeof(struct Partition));
if (ret == -1)
return -1;
map->current = part;
return part;
}