RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-14 06:24:58 +00:00
Code Issues Activity Actions

PNGLoader: Use MappedFile.

Browse source
This commit is contained in:
Andreas Kling 2019-04-03 14:15:35 +02:00
parent 3dc3754cde
commit c0009e3173
3 changed files with 21 additions and 46 deletions
Download patch file Download diff file Expand all files Collapse all files

24
AK/MappedFile.cpp
View file

@ -5,25 +5,29 @@
#include <unistd.h>
#include <stdio.h>
//#define DEBUG_MAPPED_FILE
namespace AK {
MappedFile::MappedFile(const String& file_name)
: m_file_name(file_name)
{
m_file_length = PAGE_SIZE;
m_size = PAGE_SIZE;
m_fd = open(m_file_name.characters(), O_RDONLY);
if (m_fd != -1) {
struct stat st;
fstat(m_fd, &st);
m_file_length = st.st_size;
m_map = mmap(nullptr, m_file_length, PROT_READ, MAP_SHARED, m_fd, 0);
m_size = st.st_size;
m_map = mmap(nullptr, m_size, PROT_READ, MAP_SHARED, m_fd, 0);
if (m_map == MAP_FAILED)
perror("");
}
dbgprintf("MappedFile{%s} := { m_fd=%d, m_file_length=%zu, m_map=%p }\n", m_file_name.characters(), m_fd, m_file_length, m_map);
#ifdef DEBUG_MAPPED_FILE
dbgprintf("MappedFile{%s} := { m_fd=%d, m_size=%u, m_map=%p }\n", m_file_name.characters(), m_fd, m_size, m_map);
#endif
}
MappedFile::~MappedFile()
@ -36,21 +40,23 @@ void MappedFile::unmap()
if (!is_valid())
return;
ASSERT(m_fd != -1);
int rc = munmap(m_map, m_file_length);
int rc = munmap(m_map, m_size);
ASSERT(rc == 0);
rc = close(m_fd);
ASSERT(rc == 0);
m_file_name = { };
m_file_length = 0;
m_size = 0;
m_fd = -1;
m_map = (void*)-1;
}
MappedFile::MappedFile(MappedFile&& other)
: m_file_name(move(other.m_file_name))
, m_file_length(other.m_file_length)
, m_size(other.m_size)
, m_fd(other.m_fd)
, m_map(other.m_map)
{
other.m_file_length = 0;
other.m_size = 0;
other.m_fd = -1;
other.m_map = (void*)-1;
}
@ -61,7 +67,7 @@ MappedFile& MappedFile::operator=(MappedFile&& other)
return *this;
unmap();
swap(m_file_name, other.m_file_name);
swap(m_file_length, other.m_file_length);
swap(m_size, other.m_size);
swap(m_fd, other.m_fd);
swap(m_map, other.m_map);
return *this;

4
AK/MappedFile.h
View file

@ -18,11 +18,11 @@ public:
void* pointer() { return m_map; }
const void* pointer() const { return m_map; }
size_t file_length() const { return m_file_length; }
size_t size() const { return m_size; }
private:
String m_file_name;
size_t m_file_length { 0 };
size_t m_size { 0 };
int m_fd { -1 };
void* m_map { (void*)-1 };
};

39
SharedGraphics/PNGLoader.cpp
View file

@ -1,5 +1,6 @@
#include <SharedGraphics/PNGLoader.h>
#include <AK/NetworkOrdered.h>
#include <AK/MappedFile.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
@ -101,42 +102,10 @@ static bool process_chunk(Streamer&, PNGLoadingContext& context);
RetainPtr<GraphicsBitmap> load_png(const String& path)
{
int fd = open(path.characters(), O_RDONLY);
if (fd < 0) {
perror("open");
MappedFile mapped_file(path);
if (!mapped_file.is_valid())
return nullptr;
}
struct stat st;
if (fstat(fd, &st) < 0) {
perror("fstat");
if (close(fd) < 0)
perror("close");
return nullptr;
}
if (st.st_size < 8) {
if (close(fd) < 0)
perror("close");
return nullptr;
}
auto* mapped_file = (byte*)mmap(nullptr, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
if (mapped_file == MAP_FAILED) {
if (close(fd) < 0)
perror("close");
return nullptr;
}
auto bitmap = load_png_impl(mapped_file, st.st_size);
if (munmap(mapped_file, st.st_size) < 0)
perror("munmap");
if (close(fd) < 0)
perror("close");
return bitmap;
return load_png_impl((const byte*)mapped_file.pointer(), mapped_file.size());
}
[[gnu::always_inline]] static inline byte paeth_predictor(int a, int b, int c)