ladybird/Userland/Libraries/LibCore/MappedFile.cpp
2023-04-09 22:00:54 +02:00

57 lines
1.4 KiB
C++

/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/ScopeGuard.h>
#include <LibCore/File.h>
#include <LibCore/MappedFile.h>
#include <LibCore/System.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <unistd.h>
namespace Core {
ErrorOr<NonnullRefPtr<MappedFile>> MappedFile::map(StringView path)
{
auto fd = TRY(Core::System::open(path, O_RDONLY | O_CLOEXEC, 0));
return map_from_fd_and_close(fd, path);
}
ErrorOr<NonnullRefPtr<MappedFile>> MappedFile::map_from_file(NonnullOwnPtr<Core::File> stream, StringView path)
{
return map_from_fd_and_close(stream->leak_fd(Badge<MappedFile> {}), path);
}
ErrorOr<NonnullRefPtr<MappedFile>> MappedFile::map_from_fd_and_close(int fd, [[maybe_unused]] StringView path)
{
TRY(Core::System::fcntl(fd, F_SETFD, FD_CLOEXEC));
ScopeGuard fd_close_guard = [fd] {
close(fd);
};
auto stat = TRY(Core::System::fstat(fd));
auto size = stat.st_size;
auto* ptr = TRY(Core::System::mmap(nullptr, size, PROT_READ, MAP_SHARED, fd, 0, 0, path));
return adopt_ref(*new MappedFile(ptr, size));
}
MappedFile::MappedFile(void* ptr, size_t size)
: m_data(ptr)
, m_size(size)
{
}
MappedFile::~MappedFile()
{
auto res = Core::System::munmap(m_data, m_size);
if (res.is_error())
dbgln("Failed to unmap MappedFile (@ {:p}): {}", m_data, res.error());
}
}