#include "config.h"
#include "FileStream.h"
#include <wtf/text/WTFString.h>
namespace WebCore {
FileStream::FileStream()
: m_handle(FileSystem::invalidPlatformFileHandle)
, m_bytesProcessed(0)
, m_totalBytesToRead(0)
{
}
FileStream::~FileStream()
{
close();
}
long long FileStream::getSize(const String& path, Optional<WallTime> expectedModificationTime)
{
auto modificationTime = FileSystem::getFileModificationTime(path);
if (!modificationTime)
return -1;
if (expectedModificationTime) {
if (expectedModificationTime->secondsSinceEpoch().secondsAs<time_t>() != modificationTime->secondsSinceEpoch().secondsAs<time_t>())
return -1;
}
long long length;
if (!FileSystem::getFileSize(path, length))
return -1;
return length;
}
bool FileStream::openForRead(const String& path, long long offset, long long length)
{
if (FileSystem::isHandleValid(m_handle))
return true;
m_handle = FileSystem::openFile(path, FileSystem::FileOpenMode::Read);
if (!FileSystem::isHandleValid(m_handle))
return false;
if (offset > 0) {
if (FileSystem::seekFile(m_handle, offset, FileSystem::FileSeekOrigin::Beginning) < 0)
return false;
}
m_totalBytesToRead = length;
m_bytesProcessed = 0;
return true;
}
void FileStream::close()
{
if (FileSystem::isHandleValid(m_handle)) {
FileSystem::closeFile(m_handle);
m_handle = FileSystem::invalidPlatformFileHandle;
}
}
int FileStream::read(char* buffer, int bufferSize)
{
if (!FileSystem::isHandleValid(m_handle))
return -1;
long long remaining = m_totalBytesToRead - m_bytesProcessed;
int bytesToRead = (remaining < bufferSize) ? static_cast<int>(remaining) : bufferSize;
int bytesRead = 0;
if (bytesToRead > 0)
bytesRead = FileSystem::readFromFile(m_handle, buffer, bytesToRead);
if (bytesRead < 0)
return -1;
if (bytesRead > 0)
m_bytesProcessed += bytesRead;
return bytesRead;
}
}