rlm@0: /* snes_spc 0.9.0. http://www.slack.net/~ant/ */
rlm@0: 
rlm@0: #include "wave_writer.h"
rlm@0: 
rlm@0: #include <assert.h>
rlm@0: #include <stdlib.h>
rlm@0: #include <stdio.h>
rlm@0: 
rlm@0: /* Copyright (C) 2003-2007 Shay Green. This module is free software; you
rlm@0: can redistribute it and/or modify it under the terms of the GNU Lesser
rlm@0: General Public License as published by the Free Software Foundation; either
rlm@0: version 2.1 of the License, or (at your option) any later version. This
rlm@0: module is distributed in the hope that it will be useful, but WITHOUT ANY
rlm@0: WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
rlm@0: FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
rlm@0: details. You should have received a copy of the GNU Lesser General Public
rlm@0: License along with this module; if not, write to the Free Software Foundation,
rlm@0: Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
rlm@0: 
rlm@0: enum { buf_size = 32768 * 2 };
rlm@0: enum { header_size = 0x2C };
rlm@0: 
rlm@0: typedef short sample_t;
rlm@0: 
rlm@0: static unsigned char* buf;
rlm@0: static FILE* file;
rlm@0: static long  sample_count_;
rlm@0: static long  sample_rate_;
rlm@0: static long  buf_pos;
rlm@0: static int   chan_count;
rlm@0: 
rlm@0: static void exit_with_error( const char* str )
rlm@0: {
rlm@0: 	printf( "Error: %s\n", str ); getchar();
rlm@0: 	exit( EXIT_FAILURE );
rlm@0: }
rlm@0: 
rlm@0: void wave_open( long sample_rate, const char* filename )
rlm@0: {
rlm@0: 	sample_count_ = 0;
rlm@0: 	sample_rate_  = sample_rate;
rlm@0: 	buf_pos       = header_size;
rlm@0: 	chan_count    = 1;
rlm@0: 	
rlm@0: 	buf = (unsigned char*) malloc( buf_size * sizeof *buf );
rlm@0: 	if ( !buf )
rlm@0: 		exit_with_error( "Out of memory" );
rlm@0: 	
rlm@0: 	file = fopen( filename, "wb" );
rlm@0: 	if ( !file )
rlm@0: 		exit_with_error( "Couldn't open WAVE file for writing" );
rlm@0: 	
rlm@0: 	setvbuf( file, 0, _IOFBF, 32 * 1024L );
rlm@0: }
rlm@0: 
rlm@0: void wave_enable_stereo( void )
rlm@0: {
rlm@0: 	chan_count = 2;
rlm@0: }
rlm@0: 
rlm@0: static void flush_()
rlm@0: {
rlm@0: 	if ( buf_pos && !fwrite( buf, buf_pos, 1, file ) )
rlm@0: 		exit_with_error( "Couldn't write WAVE data" );
rlm@0: 	buf_pos = 0;
rlm@0: }
rlm@0: 
rlm@0: void wave_write( short const* in, long remain )
rlm@0: {
rlm@0: 	sample_count_ += remain;
rlm@0: 	while ( remain )
rlm@0: 	{
rlm@0: 		if ( buf_pos >= buf_size )
rlm@0: 			flush_();
rlm@0: 		
rlm@0: 		{
rlm@0: 			unsigned char* p = &buf [buf_pos];
rlm@0: 			long n = (buf_size - buf_pos) / sizeof (sample_t);
rlm@0: 			if ( n > remain )
rlm@0: 				n = remain;
rlm@0: 			remain -= n;
rlm@0: 			
rlm@0: 			/* convert to LSB first format */
rlm@0: 			while ( n-- )
rlm@0: 			{
rlm@0: 				int s = *in++;
rlm@0: 				*p++ = (unsigned char) s;
rlm@0: 				*p++ = (unsigned char) (s >> 8);
rlm@0: 			}
rlm@0: 			
rlm@0: 			buf_pos = p - buf;
rlm@0: 			assert( buf_pos <= buf_size );
rlm@0: 		}
rlm@0: 	}
rlm@0: }
rlm@0: 
rlm@0: long wave_sample_count( void )
rlm@0: {
rlm@0: 	return sample_count_;
rlm@0: }
rlm@0: 
rlm@0: static void set_le32( void* p, unsigned long n )
rlm@0: {
rlm@0: 	((unsigned char*) p) [0] = (unsigned char) n;
rlm@0: 	((unsigned char*) p) [1] = (unsigned char) (n >> 8);
rlm@0: 	((unsigned char*) p) [2] = (unsigned char) (n >> 16);
rlm@0: 	((unsigned char*) p) [3] = (unsigned char) (n >> 24);
rlm@0: }
rlm@0: 
rlm@0: void wave_close( void )
rlm@0: {
rlm@0: 	if ( file )
rlm@0: 	{
rlm@0: 		/* generate header */
rlm@0: 		unsigned char h [header_size] =
rlm@0: 		{
rlm@0: 			'R','I','F','F',
rlm@0: 			0,0,0,0,        /* length of rest of file */
rlm@0: 			'W','A','V','E',
rlm@0: 			'f','m','t',' ',
rlm@0: 			0x10,0,0,0,     /* size of fmt chunk */
rlm@0: 			1,0,            /* uncompressed format */
rlm@0: 			0,0,            /* channel count */
rlm@0: 			0,0,0,0,        /* sample rate */
rlm@0: 			0,0,0,0,        /* bytes per second */
rlm@0: 			0,0,            /* bytes per sample frame */
rlm@0: 			16,0,           /* bits per sample */
rlm@0: 			'd','a','t','a',
rlm@0: 			0,0,0,0,        /* size of sample data */
rlm@0: 			/* ... */       /* sample data */
rlm@0: 		};
rlm@0: 		long ds = sample_count_ * sizeof (sample_t);
rlm@0: 		int frame_size = chan_count * sizeof (sample_t);
rlm@0: 		
rlm@0: 		set_le32( h + 0x04, header_size - 8 + ds );
rlm@0: 		h [0x16] = chan_count;
rlm@0: 		set_le32( h + 0x18, sample_rate_ );
rlm@0: 		set_le32( h + 0x1C, sample_rate_ * frame_size );
rlm@0: 		h [0x20] = frame_size;
rlm@0: 		set_le32( h + 0x28, ds );
rlm@0: 		
rlm@0: 		flush_();
rlm@0: 		
rlm@0: 		/* write header */
rlm@0: 		fseek( file, 0, SEEK_SET );
rlm@0: 		fwrite( h, sizeof h, 1, file );
rlm@0: 		
rlm@0: 		fclose( file );
rlm@0: 		file = 0;
rlm@0: 		free( buf );
rlm@0: 		buf = 0;
rlm@0: 	}
rlm@0: }