AppleWin/source/Riff.cpp

/*
AppleWin : An Apple //e emulator for Windows

Copyright (C) 1994-1996, Michael O'Brien
Copyright (C) 1999-2001, Oliver Schmidt
Copyright (C) 2002-2005, Tom Charlesworth
Copyright (C) 2006-2007, Tom Charlesworth, Michael Pohoreski

AppleWin is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

AppleWin is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with AppleWin; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/* Description: RIFF funcs
 *
 * Author: Various
 */

#include "StdAfx.h"
#include "Riff.h"

static HANDLE g_hRiffFile = INVALID_HANDLE_VALUE;
static DWORD dwTotalOffset;
static DWORD dwDataOffset;
static unsigned int g_NumChannels = 2;

bool RiffInitWriteFile(const char* pszFile, unsigned int sample_rate, unsigned int NumChannels)
{
	g_hRiffFile = CreateFile(pszFile, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);

	if(g_hRiffFile == INVALID_HANDLE_VALUE)
		return false;

	g_NumChannels = NumChannels;

	//

	UINT32 temp32;
	UINT16 temp16;

	DWORD dwNumberOfBytesWritten;

	WriteFile(g_hRiffFile, "RIFF", 4, &dwNumberOfBytesWritten, NULL);

	temp32 = 0;				// total size
	dwTotalOffset = SetFilePointer(g_hRiffFile, 0, NULL, FILE_CURRENT);
	WriteFile(g_hRiffFile, &temp32, 4, &dwNumberOfBytesWritten, NULL);

	WriteFile(g_hRiffFile, "WAVE", 4, &dwNumberOfBytesWritten, NULL);

	//

	WriteFile(g_hRiffFile, "fmt ", 4, &dwNumberOfBytesWritten, NULL);

	temp32 = 16;			// format length
	WriteFile(g_hRiffFile, &temp32, 4, &dwNumberOfBytesWritten, NULL);

	temp16 = 1;				// PCM format
	WriteFile(g_hRiffFile, &temp16, 2, &dwNumberOfBytesWritten, NULL);

	temp16 = NumChannels;		// channels
	WriteFile(g_hRiffFile, &temp16, 2, &dwNumberOfBytesWritten, NULL);

	temp32 = sample_rate;	// sample rate
	WriteFile(g_hRiffFile, &temp32, 4, &dwNumberOfBytesWritten, NULL);

	temp32 = sample_rate * 2 * NumChannels;	// bytes/second
	WriteFile(g_hRiffFile, &temp32, 4, &dwNumberOfBytesWritten, NULL);

	temp16 = 2 * NumChannels;	// block align
	WriteFile(g_hRiffFile, &temp16, 2, &dwNumberOfBytesWritten, NULL);

	temp16 = 16;			// bits/sample
	WriteFile(g_hRiffFile, &temp16, 2, &dwNumberOfBytesWritten, NULL);

	//

	WriteFile(g_hRiffFile, "data", 4, &dwNumberOfBytesWritten, NULL);

	temp32 = 0;				// data length
	dwDataOffset = SetFilePointer(g_hRiffFile, 0, NULL, FILE_CURRENT);
	WriteFile(g_hRiffFile, &temp32, 4, &dwNumberOfBytesWritten, NULL);

	return true;
}

bool RiffFinishWriteFile()
{
	if(g_hRiffFile == INVALID_HANDLE_VALUE)
		return false;

	//

	UINT32 temp32;

	DWORD dwNumberOfBytesWritten;
	
	DWORD fileSize = SetFilePointer(g_hRiffFile, 0, NULL, FILE_END);

	temp32 = fileSize - (dwTotalOffset + 4);
	SetFilePointer(g_hRiffFile, dwTotalOffset, NULL, FILE_BEGIN);
	WriteFile(g_hRiffFile, &temp32, 4, &dwNumberOfBytesWritten, NULL);

	temp32 = fileSize - (dwDataOffset + 4);
	SetFilePointer(g_hRiffFile, dwDataOffset, NULL, FILE_BEGIN);
	WriteFile(g_hRiffFile, &temp32, 4, &dwNumberOfBytesWritten, NULL);

	return CloseHandle(g_hRiffFile) ? true : false;
}

bool RiffPutSamples(const short* buf, unsigned int uSamples)
{
	if(g_hRiffFile == INVALID_HANDLE_VALUE)
		return false;

	//

	DWORD dwNumberOfBytesWritten;

	BOOL bRes = WriteFile(
		g_hRiffFile,
		buf,
		uSamples * sizeof(short) * g_NumChannels,
		&dwNumberOfBytesWritten,
		NULL);

	return true;
}