ladybird/AK/MappedFile.cpp
Andreas Kling 73fdbba59c AK: Rename <AK/AKString.h> to <AK/String.h>
This was a workaround to be able to build on case-insensitive file
systems where it might get confused about <string.h> vs <String.h>.

Let's just not support building that way, so String.h can have an
objectively nicer name. :^)
2019-09-06 15:36:54 +02:00

72 lines
1.3 KiB
C++

#include <AK/String.h>
#include <AK/MappedFile.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)
{
m_size = PAGE_SIZE;
int fd = open_with_path_length(file_name.characters_without_null_termination(), file_name.length(), O_RDONLY | O_CLOEXEC, 0);
if (fd == -1) {
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)
perror("mmap");
#ifdef DEBUG_MAPPED_FILE
dbgprintf("MappedFile{%s} := { fd=%d, m_size=%u, m_map=%p }\n", file_name.characters(), 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;
}
}