bool
PartitionMap::Check(off_t sessionSize) const
{
int32 partitionCount = CountPartitions();
// 1. check partition locations
for (int32 i = 0; i < partitionCount; i++) {
if (!PartitionAt(i)->CheckLocation(sessionSize))
return false;
}
// 2. check overlapping of partitions and location of partition tables
bool result = true;
Partition** byOffset = new(nothrow) Partition*[partitionCount];
off_t* tableOffsets = new(nothrow) off_t[partitionCount - 3];
if (byOffset && tableOffsets) {
// fill the arrays
int32 byOffsetCount = 0;
int32 tableOffsetCount = 1; // primary partition table
tableOffsets[0] = 0;
for (int32 i = 0; i < partitionCount; i++) {
Partition* partition = (Partition*)PartitionAt(i);
if (!partition->IsExtended())
byOffset[byOffsetCount++] = partition;
// add only logical partition partition table locations
if (i >= 4) {
tableOffsets[tableOffsetCount++]
= partition->PartitionTableOffset();
}
}
// sort the arrays
qsort(byOffset, byOffsetCount, sizeof(Partition*),
cmp_partition_offset);
qsort(tableOffsets, tableOffsetCount, sizeof(off_t), cmp_offset);
// check for overlappings
off_t nextOffset = 0;
for (int32 i = 0; i < byOffsetCount; i++) {
Partition* partition = byOffset[i];
if (partition->Offset() < nextOffset && i > 0) {
Partition* previousPartition = byOffset[i - 1];
off_t previousSize = previousPartition->Size()
- (nextOffset - partition->Offset());
TRACE(("intel: PartitionMap::Check(): "));
if (previousSize == 0) {
previousPartition->Unset();
TRACE(("partition offset hides previous partition."
" Removing previous partition from disk layout.\n"));
} else {
TRACE(("overlapping partitions! Setting partition %ld "
"size to %lld\n", i - 1, previousSize));
previousPartition->SetSize(previousSize);
}
}
nextOffset = partition->Offset() + partition->Size();
}
// check uniqueness of partition table offsets and whether they lie
// outside of the non-extended partitions
if (result) {
for (int32 i = 0; i < tableOffsetCount; i++) {
if (i > 0 && tableOffsets[i] == tableOffsets[i - 1]) {
TRACE(("intel: PartitionMap::Check(): same partition table "
"for different extended partitions!\n"));
result = false;
break;
} else if (is_inside_partitions(tableOffsets[i],
(const Partition**)byOffset, byOffsetCount)) {
TRACE(("intel: PartitionMap::Check(): a partition table "
"lies inside a non-extended partition!\n"));
result = false;
break;
}
}
}
} else
result = false; // no memory: assume failure
// cleanup
delete[] byOffset;
delete[] tableOffsets;
return result;
}
