ladybird/Kernel/FileSystem/SysFS/Subsystems/Firmware/BIOS/Component.cpp

/*
 * Copyright (c) 2022, Liav A. <liavalb@hotmail.co.il>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <AK/StringView.h>
#include <Kernel/FileSystem/OpenFileDescription.h>
#include <Kernel/FileSystem/SysFS/Subsystems/Firmware/BIOS/Component.h>
#include <Kernel/Firmware/BIOS.h>
#include <Kernel/KBufferBuilder.h>
#include <Kernel/Memory/MemoryManager.h>
#include <Kernel/Memory/TypedMapping.h>
#include <Kernel/Sections.h>

namespace Kernel {

UNMAP_AFTER_INIT BIOSSysFSComponent::BIOSSysFSComponent()
{
}

ErrorOr<size_t> BIOSSysFSComponent::read_bytes(off_t offset, size_t count, UserOrKernelBuffer& buffer, OpenFileDescription*) const
{
    auto blob = TRY(try_to_generate_buffer());

    if ((size_t)offset >= blob->size())
        return 0;

    ssize_t nread = min(static_cast<off_t>(blob->size() - offset), static_cast<off_t>(count));
    TRY(buffer.write(blob->data() + offset, nread));
    return nread;
}

}