static bool_t dos_partition(struct disk * disk, size_t sector, size_t relative)
{
struct dos_partition_mbr mbr;
struct partition * part;
size_t start;
int i;
if(!disk || !disk->name)
return FALSE;
if((disk->sector_size <= 0) || (disk->sector_count <=0))
return FALSE;
if((!disk->read_sectors) || (!disk->write_sectors))
return FALSE;
if(disk_read(disk, (u8_t *)(&mbr), (loff_t)(sector * disk->sector_size) , sizeof(struct dos_partition_mbr)) != sizeof(struct dos_partition_mbr))
return FALSE;
/*
* check dos partition's signature
*/
if((mbr.signature[0] != 0x55) || mbr.signature[1] != 0xaa)
return FALSE;
for(i=0; i<4; i++)
{
if((mbr.entry[i].type != 0) && (is_dos_extended(mbr.entry[i].type)==FALSE))
{
part = malloc(sizeof(struct partition));
if(!part)
return FALSE;
strlcpy((char *)part->name, (const char *)"", sizeof(part->name));
part->sector_from = sector + ((mbr.entry[i].start[3] << 24) | (mbr.entry[i].start[2] << 16) | (mbr.entry[i].start[1] << 8) | (mbr.entry[i].start[0] << 0));
part->sector_to = part->sector_from + ((mbr.entry[i].length[3] << 24) | (mbr.entry[i].length[2] << 16) | (mbr.entry[i].length[1] << 8) | (mbr.entry[i].length[0] << 0)) - 1;
part->sector_size = disk->sector_size;
list_add_tail(&part->entry, &(disk->info.entry));
}
}
for(i=0; i<4; i++)
{
if(is_dos_extended(mbr.entry[i].type)==TRUE)
{
start = ((mbr.entry[i].start[3] << 24) | (mbr.entry[i].start[2] << 16) | (mbr.entry[i].start[1] << 8) | (mbr.entry[i].start[0] << 0)) + relative;
return dos_partition(disk, start, (sector == 0) ? start : relative);
}
}
return TRUE;
}
/*
* Walk partition tables and invoke a callback for each.
*/
static void
walk_partitions(int fd, int startsec, uint_t secsz,
int (*f)(void *, int, uint_t, uint_t), void *arg)
{
uint32_t buf[1024/4];
int bufsize = 1024;
struct mboot *mboot = (struct mboot *)&buf[0];
struct ipart ipart[FD_NUMPART];
uint_t sec = startsec;
uint_t lastsec = sec + 1;
uint_t relsect;
int ext = 0;
int systid;
boolean_t valid;
int i;
while (sec != lastsec) {
if (pread(fd, buf, bufsize, (off_t)sec * secsz) != bufsize) {
break;
}
lastsec = sec;
if (ltohs(mboot->signature) != MBB_MAGIC) {
break;
}
bcopy(mboot->parts, ipart, FD_NUMPART * sizeof (struct ipart));
for (i = 0; i < FD_NUMPART; i++) {
systid = ipart[i].systid;
relsect = sec + ltohi(ipart[i].relsect);
if (systid == 0) {
continue;
}
valid = B_TRUE;
if (is_dos_extended(systid) && (sec == lastsec)) {
sec = startsec + ltohi(ipart[i].relsect);
if (ext++ == 0) {
relsect = startsec = sec;
} else {
valid = B_FALSE;
}
}
if (valid && f(arg, ipart[i].systid, relsect,
ltohi(ipart[i].numsect)) == WALK_TERMINATE) {
return;
}
}
}
}