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/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/MappedFile.h>
#include <AK/ScopeGuard.h>
#include <AK/String.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
namespace AK {
ErrorOr<NonnullRefPtr<MappedFile>> MappedFile::map(String const& path)
{
int fd = open(path.characters(), O_RDONLY | O_CLOEXEC, 0);
if (fd < 0)
return Error::from_errno(errno);
return map_from_fd_and_close(fd, path);
}
ErrorOr<NonnullRefPtr<MappedFile>> MappedFile::map_from_fd_and_close(int fd, [[maybe_unused]] String const& path)
{
if (fcntl(fd, F_SETFD, FD_CLOEXEC) < 0)
return Error::from_errno(errno);
ScopeGuard fd_close_guard = [fd] {
close(fd);
};
struct stat st;
if (fstat(fd, &st) < 0)
return Error::from_errno(errno);
auto size = st.st_size;
auto* ptr = mmap(nullptr, size, PROT_READ, MAP_SHARED, fd, 0);
if (ptr == MAP_FAILED)
return Error::from_errno(errno);
#ifdef __serenity__
if (set_mmap_name(ptr, size, path.characters()) < 0) {
perror("set_mmap_name");
}
#endif
return adopt_ref(*new MappedFile(ptr, size));
}
MappedFile::MappedFile(void* ptr, size_t size)
: m_data(ptr)
, m_size(size)
{
}
MappedFile::~MappedFile()
{
auto rc = munmap(m_data, m_size);
VERIFY(rc == 0);
}
}
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