nod/lib/FileIOFILE.cpp

184 lines
5.1 KiB
C++

#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include "nod/Util.hpp"
#include "nod/IFileIO.hpp"
namespace nod
{
class FileIOFILE : public IFileIO
{
SystemString m_path;
int64_t m_maxWriteSize;
public:
FileIOFILE(SystemStringView path, int64_t maxWriteSize)
: m_path(path), m_maxWriteSize(maxWriteSize) {}
bool exists()
{
FILE* fp = fopen(m_path.c_str(), "rb");
if (!fp)
return false;
fclose(fp);
return true;
}
uint64_t size()
{
FILE* fp = fopen(m_path.c_str(), "rb");
if (!fp)
return 0;
FSeek(fp, 0, SEEK_END);
uint64_t result = FTell(fp);
fclose(fp);
return result;
}
struct WriteStream : public IFileIO::IWriteStream
{
FILE* fp;
int64_t m_maxWriteSize;
WriteStream(SystemStringView path, int64_t maxWriteSize, bool& err)
: m_maxWriteSize(maxWriteSize)
{
fp = fopen(path.data(), "wb");
if (!fp)
{
LogModule.report(logvisor::Error, _S("unable to open '%s' for writing"), path.data());
err = true;
}
}
WriteStream(SystemStringView path, uint64_t offset, int64_t maxWriteSize, bool& err)
: m_maxWriteSize(maxWriteSize)
{
fp = fopen(path.data(), "ab");
if (!fp)
goto FailLoc;
fclose(fp);
fp = fopen(path.data(), "r+b");
if (!fp)
goto FailLoc;
FSeek(fp, offset, SEEK_SET);
return;
FailLoc:
LogModule.report(logvisor::Error, _S("unable to open '%s' for writing"), path.data());
err = true;
}
~WriteStream()
{
fclose(fp);
}
uint64_t write(const void* buf, uint64_t length)
{
if (m_maxWriteSize >= 0)
{
if (FTell(fp) + length > m_maxWriteSize)
{
LogModule.report(logvisor::Error, _S("write operation exceeds file's %" PRIi64 "-byte limit"), m_maxWriteSize);
return 0;
}
}
return fwrite(buf, 1, length, fp);
}
};
std::unique_ptr<IWriteStream> beginWriteStream() const
{
bool Err = false;
auto ret = std::unique_ptr<IWriteStream>(new WriteStream(m_path, m_maxWriteSize, Err));
if (Err)
return {};
return ret;
}
std::unique_ptr<IWriteStream> beginWriteStream(uint64_t offset) const
{
bool Err = false;
auto ret = std::unique_ptr<IWriteStream>(new WriteStream(m_path, offset, m_maxWriteSize, Err));
if (Err)
return {};
return ret;
}
struct ReadStream : public IFileIO::IReadStream
{
FILE* fp;
ReadStream(SystemStringView path, bool& err)
{
fp = fopen(path.data(), "rb");
if (!fp)
{
err = true;
LogModule.report(logvisor::Error, _S("unable to open '%s' for reading"), path.data());
}
}
ReadStream(SystemStringView path, uint64_t offset, bool& err)
: ReadStream(path, err)
{
if (err)
return;
FSeek(fp, offset, SEEK_SET);
}
~ReadStream()
{
fclose(fp);
}
void seek(int64_t offset, int whence)
{
FSeek(fp, offset, whence);
}
uint64_t position() const
{
return FTell(fp);
}
uint64_t read(void* buf, uint64_t length)
{
return fread(buf, 1, length, fp);
}
uint64_t copyToDisc(IPartWriteStream& discio, uint64_t length)
{
uint64_t written = 0;
uint8_t buf[0x7c00];
while (length)
{
uint64_t thisSz = nod::min(uint64_t(0x7c00), length);
if (read(buf, thisSz) != thisSz)
{
LogModule.report(logvisor::Error, "unable to read enough from file");
return written;
}
if (discio.write(buf, thisSz) != thisSz)
{
LogModule.report(logvisor::Error, "unable to write enough to disc");
return written;
}
length -= thisSz;
written += thisSz;
}
return written;
}
};
std::unique_ptr<IReadStream> beginReadStream() const
{
bool Err = false;
auto ret = std::unique_ptr<IReadStream>(new ReadStream(m_path, Err));
if (Err)
return {};
return ret;
}
std::unique_ptr<IReadStream> beginReadStream(uint64_t offset) const
{
bool Err = false;
auto ret = std::unique_ptr<IReadStream>(new ReadStream(m_path, offset, Err));
if (Err)
return {};
return ret;
}
};
std::unique_ptr<IFileIO> NewFileIO(SystemStringView path, int64_t maxWriteSize)
{
return std::unique_ptr<IFileIO>(new FileIOFILE(path, maxWriteSize));
}
}