DefaultIOStream.cpp

/*
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Open Asset Import Library (assimp)
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  following disclaimer.

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OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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*/
/** @file  DefaultIOStream.cpp
 *  @brief Default File I/O implementation for #Importer 
 */

#include "AssimpPCH.h"

#include "DefaultIOStream.h"
#include <sys/types.h> 
#include <sys/stat.h> 

using namespace Assimp;

// ----------------------------------------------------------------------------------
DefaultIOStream::~DefaultIOStream()
{
	if (mFile) {
		::fclose(mFile);
	}
}

// ----------------------------------------------------------------------------------
size_t DefaultIOStream::Read(void* pvBuffer, 
	size_t pSize, 
	size_t pCount)
{
	ai_assert(NULL != pvBuffer && 0 != pSize && 0 != pCount);
	return (mFile ? ::fread(pvBuffer, pSize, pCount, mFile) : 0);
}

// ----------------------------------------------------------------------------------
size_t DefaultIOStream::Write(const void* pvBuffer, 
	size_t pSize,
	size_t pCount)
{
	ai_assert(NULL != pvBuffer && 0 != pSize && 0 != pCount);
	return (mFile ? ::fwrite(pvBuffer, pSize, pCount, mFile) : 0);
}

// ----------------------------------------------------------------------------------
aiReturn DefaultIOStream::Seek(size_t pOffset,
	 aiOrigin pOrigin)
{
	if (!mFile) {
		return AI_FAILURE;
	}

	// Just to check whether our enum maps one to one with the CRT constants
	BOOST_STATIC_ASSERT(aiOrigin_CUR == SEEK_CUR && 
		aiOrigin_END == SEEK_END && aiOrigin_SET == SEEK_SET);

	// do the seek
	return (0 == ::fseek(mFile, (long)pOffset,(int)pOrigin) ? AI_SUCCESS : AI_FAILURE);
}

// ----------------------------------------------------------------------------------
size_t DefaultIOStream::Tell() const
{
	if (!mFile) {
		return 0;
	}
	return ::ftell(mFile);
}

// ----------------------------------------------------------------------------------
size_t DefaultIOStream::FileSize() const
{
	if (! mFile || mFilename.empty()) {
		return 0;
	}
	
	if (SIZE_MAX == cachedSize) {

		// TODO: Is that really faster if we're already owning a handle to the file?
#if defined _WIN32 && !defined __GNUC__
		struct __stat64 fileStat; 
		int err = _stat64(  mFilename.c_str(), &fileStat ); 
		if (0 != err) 
			return 0; 
		cachedSize = (size_t) (fileStat.st_size); 
#else
		struct stat fileStat; 
		int err = stat(mFilename.c_str(), &fileStat ); 
		if (0 != err) 
			return 0; 
		cachedSize = (size_t) (fileStat.st_size); 
#endif
	}
	return cachedSize;
}

// ----------------------------------------------------------------------------------
void DefaultIOStream::Flush()
{
	if (mFile) {
		::fflush(mFile);
	}
}

// ----------------------------------------------------------------------------------