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vcmi/lib/filesystem/CFileInputStream.cpp
AlexVinS a00dbd3dd1 Merge remote-tracking branch 'remotes/origin/develop' into feature/VCMIMapFormat1
Conflicts:
	lib/CMakeLists.txt
	lib/VCMI_lib.cbp
	lib/filesystem/CFileInputStream.cpp
	lib/filesystem/CZipLoader.cpp
	lib/rmg/CRmgTemplateZone.cpp
	vcmi.workspace
2016-02-08 10:17:25 +03:00

55 lines
1.2 KiB
C++

#include "StdInc.h"
#include "CFileInputStream.h"
CFileInputStream::CFileInputStream(const boost::filesystem::path & file, si64 start, si64 size)
: dataStart{start},
dataSize{size},
fileStream{file, std::ios::in | std::ios::binary}
{
if (fileStream.fail())
throw std::runtime_error("File " + file.string() + " isn't available.");
if (dataSize == 0)
{
fileStream.seekg(0, std::ios::end);
dataSize = tell();
}
fileStream.seekg(dataStart, std::ios::beg);
}
si64 CFileInputStream::read(ui8 * data, si64 size)
{
si64 origin = tell();
si64 toRead = std::min(dataSize - origin, size);
fileStream.read(reinterpret_cast<char *>(data), toRead);
return fileStream.gcount();
}
si64 CFileInputStream::seek(si64 position)
{
fileStream.seekg(dataStart + std::min(position, dataSize));
return tell();
}
si64 CFileInputStream::tell()
{
return static_cast<si64>(fileStream.tellg()) - dataStart;
}
si64 CFileInputStream::skip(si64 delta)
{
si64 origin = tell();
//ensure that we're not seeking past the end of real data
si64 toSeek = std::min(dataSize - origin, delta);
fileStream.seekg(toSeek, std::ios::cur);
return tell() - origin;
}
si64 CFileInputStream::getSize()
{
return dataSize;
}