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/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/MappedFile.h>
#include <AK/String.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
//#define DEBUG_MAPPED_FILE
namespace AK {
MappedFile::MappedFile(const StringView& file_name)
{
int fd = open_with_path_length(file_name.characters_without_null_termination(), file_name.length(), O_RDONLY | O_CLOEXEC, 0);
if (fd == -1) {
m_errno = errno;
perror("open");
return;
}
struct stat st;
fstat(fd, &st);
m_size = st.st_size;
m_map = mmap(nullptr, m_size, PROT_READ, MAP_SHARED, fd, 0);
if (m_map == MAP_FAILED) {
m_errno = errno;
perror("mmap");
}
#ifdef DEBUG_MAPPED_FILE
dbgln("MappedFile(\"{}\") := ( fd={}, m_size={}, m_map={} )", file_name, fd, m_size, m_map);
#endif
close(fd);
}
MappedFile::~MappedFile()
{
unmap();
}
void MappedFile::unmap()
{
if (!is_valid())
return;
int rc = munmap(m_map, m_size);
ASSERT(rc == 0);
m_size = 0;
m_map = (void*)-1;
}
MappedFile::MappedFile(MappedFile&& other)
: m_size(other.m_size)
, m_map(other.m_map)
{
other.m_size = 0;
other.m_map = (void*)-1;
}
MappedFile& MappedFile::operator=(MappedFile&& other)
{
if (this == &other)
return *this;
unmap();
swap(m_size, other.m_size);
swap(m_map, other.m_map);
return *this;
}
}
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