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/*
* Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibCore/AnonymousBuffer.h>
#include <LibIPC/Decoder.h>
#include <LibIPC/Encoder.h>
#include <LibIPC/File.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/mman.h>
#if defined(__serenity__)
# include <serenity.h>
#endif
#if defined(__linux__) && !defined(MFD_CLOEXEC)
# include <linux/memfd.h>
# include <sys/syscall.h>
static int memfd_create(const char* name, unsigned int flags)
{
return syscall(SYS_memfd_create, name, flags);
}
#endif
namespace Core {
AnonymousBuffer AnonymousBuffer::create_with_size(size_t size)
{
int fd = -1;
#if defined(__serenity__)
fd = anon_create(round_up_to_power_of_two(size, PAGE_SIZE), O_CLOEXEC);
if (fd < 0) {
perror("anon_create");
return {};
}
#elif defined(__linux__)
fd = memfd_create("", MFD_CLOEXEC);
if (fd < 0) {
perror("memfd_create");
return {};
}
if (ftruncate(fd, size) < 0) {
close(fd);
perror("ftruncate");
return {};
}
#endif
if (fd < 0)
return {};
return create_from_anon_fd(fd, size);
}
RefPtr<AnonymousBufferImpl> AnonymousBufferImpl::create(int fd, size_t size)
{
auto* data = mmap(nullptr, round_up_to_power_of_two(size, PAGE_SIZE), PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, fd, 0);
if (data == MAP_FAILED) {
perror("mmap");
return {};
}
return adopt(*new AnonymousBufferImpl(fd, size, data));
}
AnonymousBufferImpl::~AnonymousBufferImpl()
{
if (m_fd != -1) {
auto rc = close(m_fd);
VERIFY(rc == 0);
}
auto rc = munmap(m_data, round_up_to_power_of_two(m_size, PAGE_SIZE));
VERIFY(rc == 0);
}
AnonymousBuffer AnonymousBuffer::create_from_anon_fd(int fd, size_t size)
{
auto impl = AnonymousBufferImpl::create(fd, size);
if (!impl)
return {};
return AnonymousBuffer(impl.release_nonnull());
}
AnonymousBuffer::AnonymousBuffer(NonnullRefPtr<AnonymousBufferImpl> impl)
: m_impl(move(impl))
{
}
AnonymousBufferImpl::AnonymousBufferImpl(int fd, size_t size, void* data)
: m_fd(fd)
, m_size(size)
, m_data(data)
{
}
AnonymousBuffer::~AnonymousBuffer()
{
}
}
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