irrlicht/source/Irrlicht/CMemoryReadFile.cpp

112 lines
1.9 KiB
C++

// Copyright (C) 2002-2007 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h
#include "CMemoryReadFile.h"
#include "irrString.h"
namespace irr
{
namespace io
{
CMemoryReadFile::CMemoryReadFile(void* memory, long len, const c8* fileName, bool d)
: Buffer(memory), Len(len), Pos(0), deleteMemoryWhenDropped(d)
{
#ifdef _DEBUG
setDebugName("CReadFile");
#endif
Filename = fileName;
}
CMemoryReadFile::~CMemoryReadFile()
{
if (deleteMemoryWhenDropped)
delete [] (c8*)Buffer;
}
//! returns how much was read
s32 CMemoryReadFile::read(void* buffer, u32 sizeToRead)
{
s32 amount = static_cast<s32>(sizeToRead);
if (Pos + amount > Len)
amount -= Pos + amount - Len;
if (amount <= 0)
return 0;
c8* p = (c8*)Buffer;
memcpy(buffer, p + Pos, amount);
Pos += amount;
return amount;
}
//! changes position in file, returns true if successful
//! if relativeMovement==true, the pos is changed relative to current pos,
//! otherwise from begin of file
bool CMemoryReadFile::seek(long finalPos, bool relativeMovement)
{
if (relativeMovement)
{
if (Pos + finalPos > Len)
return false;
Pos += finalPos;
}
else
{
if (finalPos > Len)
return false;
Pos = finalPos;
}
return true;
}
//! returns size of file
long CMemoryReadFile::getSize() const
{
return Len;
}
//! returns where in the file we are.
long CMemoryReadFile::getPos() const
{
return Pos;
}
//! returns name of file
const c8* CMemoryReadFile::getFileName() const
{
return Filename.c_str();
}
IReadFile* createMemoryReadFile(void* memory, long size, const c8* fileName, bool deleteMemoryWhenDropped)
{
CMemoryReadFile* file = new CMemoryReadFile(memory, size, fileName, deleteMemoryWhenDropped);
return file;
}
} // end namespace io
} // end namespace irr