Added new SHN decoder (Derek Scott)

Sound/SoundFile/ShnFile.mm

@@ -0,0 +1,158 @@
+//
+//  ShnFile.mm
+//  Cog
+//
+//  Created by Vincent Spader on 6/6/05.
+//  Copyright 2005 Vincent Spader All rights reserved.
+//
+
+#import "ShnFile.h"
+
+@implementation ShnFile
+
+- (BOOL)open:(const char *)filename
+{
+	if ([self readInfo:filename] == NO)
+		return NO;
+	
+	return YES;
+}
+
+- (BOOL)readInfo:(const char *)filename
+{
+	decoder	= new shn_reader;
+	
+	if (!decoder)
+	{
+		return NO;
+	}
+	
+	decoder->open(filename, true);
+	
+	bufferSize = decoder->shn_get_buffer_block_size(512);
+	buffer = malloc(bufferSize);
+	
+	unsigned int length;
+	int chan;
+	float freq;
+	int bps;
+	
+	decoder->file_info(NULL, &chan, &freq, NULL, &bps, NULL);
+	
+	/*NSLog(@"chan: %d",chan);
+	NSLog(@"freq: %f",freq);
+	NSLog(@"bps: %d",bps);*/
+
+	channels = chan;
+	frequency = (int)freq;
+	bitsPerSample = bps;
+	
+	/*NSLog(@"channels: %d",channels);
+	NSLog(@"frequency: %f",(double)frequency);
+	NSLog(@"bitsPerSample: %d",bitsPerSample);*/
+
+	length = decoder->shn_get_song_length();
+	//NSLog(@"length: %d",length);
+	totalSize = (((double)(length)*frequency)/1000.0) * channels * (bitsPerSample/8);
+	bitRate = (int)((double)totalSize/((double)length/1000.0));
+	
+	/*NSLog(@"totalSize: %d",totalSize);
+	NSLog(@"bitRate: %d",bitRate);*/
+	
+	decoder->go();
+	
+	return YES;
+}
+
+- (int)fillBuffer:(void *)buf ofSize:(UInt32)size
+{
+
+	//long numread = bufferAmount;
+	//long count = 0;
+	long numread, count;
+	bufferAmount = 0;
+	inputBuffer = malloc(bufferSize);
+	
+	//Fill from buffer, going by bufferAmount
+	//if still needs more, decode and repeat
+	if (bufferAmount == 0)
+	{
+		//bufferAmount = shn_read(handle, buffer, bufferSize);
+		while((bufferAmount = decoder->read(inputBuffer, bufferSize)) == (unsigned)(-1))
+		{
+			bufferAmount = decoder->read(inputBuffer, bufferSize);
+		}
+		if (bufferAmount == 0)
+			return 0;
+		else if(bufferAmount == (unsigned)( -2))
+		{
+			//NSLog(@"closing file, eof");
+			return -2;
+		}
+		else
+		{
+			memcpy(buffer, inputBuffer, bufferAmount);
+			free(inputBuffer);
+		}
+	}
+	
+	//NSLog(@"bufferAmount: %d",bufferAmount);
+	
+	
+	count = bufferAmount;
+	if (bufferAmount > size)
+	{
+		count = size;
+	}
+	
+	memcpy(buf, buffer, count);
+	
+	bufferAmount -= count;
+	
+	if (bufferAmount > 0)
+		memmove(buffer, (&((char *)buffer)[count]), bufferAmount);
+	
+	if (count < size)
+		numread = [self fillBuffer:(&((char *)buf)[count]) ofSize:(size - count)];
+	else
+		numread = 0;
+	
+	return count + numread;
+}
+
+- (double)seekToTime:(double)milliseconds
+{
+	unsigned int sec;
+	
+	/*if (!shn_seekable(handle))
+		return -1.0;*/
+	
+	sec = (int)(milliseconds/1000.0);
+	
+	//shn_seek(handle, sec);
+	
+	decoder->seek(sec);
+	
+	return (sec * 1000.0);
+}
+
+- (void)close
+{
+	if(decoder)
+	{
+		decoder->exit();
+		delete decoder;
+		decoder	= NULL;
+	}
+
+	if (buffer)
+	{
+		free(buffer);
+		buffer = NULL;
+	}
+	
+	/*if (shn_cleanup_decoder(handle))
+		shn_unload(handle);*/
+}
+
+@end