ladybird/Userland/Libraries/LibPartition/EBRPartitionTable.cpp
Andreas Kling 456f12c5c8 LibPartition: Make Kernel parts const-correct re: StorageDevice&
We can't do I/O with a const StorageDevice&, so it has to be non-const.
2023-02-21 00:54:04 +01:00

91 lines
3.1 KiB
C++

/*
* Copyright (c) 2020-2022, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibPartition/EBRPartitionTable.h>
#ifndef KERNEL
# include <LibCore/DeprecatedFile.h>
#endif
namespace Partition {
#ifdef KERNEL
ErrorOr<NonnullOwnPtr<EBRPartitionTable>> EBRPartitionTable::try_to_initialize(Kernel::StorageDevice& device)
{
auto table = TRY(adopt_nonnull_own_or_enomem(new (nothrow) EBRPartitionTable(device)));
#else
ErrorOr<NonnullOwnPtr<EBRPartitionTable>> EBRPartitionTable::try_to_initialize(NonnullRefPtr<Core::DeprecatedFile> device_file)
{
auto table = TRY(adopt_nonnull_own_or_enomem(new (nothrow) EBRPartitionTable(move(device_file))));
#endif
if (table->is_protective_mbr())
return Error::from_errno(ENOTSUP);
if (!table->is_valid())
return Error::from_errno(EINVAL);
return table;
}
#ifdef KERNEL
void EBRPartitionTable::search_extended_partition(Kernel::StorageDevice& device, MBRPartitionTable& checked_ebr, u64 current_block_offset, size_t limit)
#else
void EBRPartitionTable::search_extended_partition(NonnullRefPtr<Core::DeprecatedFile> device, MBRPartitionTable& checked_ebr, u64 current_block_offset, size_t limit)
#endif
{
if (limit == 0)
return;
// EBRs should not carry more than 2 partitions (because they need to form a linked list)
VERIFY(checked_ebr.partitions_count() <= 2);
auto checked_logical_partition = checked_ebr.partition(0);
// If we are pointed to an invalid logical partition, something is seriously wrong.
VERIFY(checked_logical_partition.has_value());
m_partitions.append(checked_logical_partition.value().offset(current_block_offset));
if (!checked_ebr.contains_ebr())
return;
current_block_offset += checked_ebr.partition(1).value().start_block();
auto next_ebr = MBRPartitionTable::try_to_initialize(device, current_block_offset);
if (!next_ebr)
return;
search_extended_partition(device, *next_ebr, current_block_offset, (limit - 1));
}
#ifdef KERNEL
EBRPartitionTable::EBRPartitionTable(Kernel::StorageDevice& device)
#else
EBRPartitionTable::EBRPartitionTable(NonnullRefPtr<Core::DeprecatedFile> device)
#endif
: MBRPartitionTable(device)
{
if (!is_header_valid())
return;
m_valid = true;
VERIFY(partitions_count() == 0);
auto& header = this->header();
for (size_t index = 0; index < 4; index++) {
auto& entry = header.entry[index];
// Start enumerating all logical partitions
if (entry.type == 0xf) {
auto checked_ebr = MBRPartitionTable::try_to_initialize(device, entry.offset);
if (!checked_ebr)
continue;
// It's quite unlikely to see that amount of partitions, so stop at 128 partitions.
search_extended_partition(device, *checked_ebr, entry.offset, 128);
continue;
}
if (entry.offset == 0x00) {
continue;
}
MUST(m_partitions.try_empend(entry.offset, (entry.offset + entry.length) - 1, entry.type));
}
}
EBRPartitionTable::~EBRPartitionTable() = default;
}