MetadataUtils.cs

using System;
/*
** MetadataUtils.cs
**
** Copyright (c) 2010-2016 Peter McQuillan
**
** All Rights Reserved.
**                       
** Distributed under the BSD Software License (see license.txt)  
***/

class MetadataUtils
{
	internal static int read_metadata_buff(WavpackContext wpc, WavpackMetadata wpmd)
	{
		long bytes_to_read;
		short tchar;
		
		if (wpmd.bytecount >= wpc.stream.wphdr.ckSize)
		{
			// we have read all the data in this block
			return Defines.FALSE;
		}
		
		try
		{
			wpmd.id = (short) wpc.infile.ReadByte();
			tchar = (short) wpc.infile.ReadByte();
		}
		catch (System.Exception)
		{
			wpmd.status = 1;
			return Defines.FALSE;
		}
		
		wpmd.bytecount += 2;
		
		wpmd.byte_length = tchar << 1;
		
		if ((wpmd.id & Defines.ID_LARGE) != 0)
		{
			wpmd.id &= (short)~ Defines.ID_LARGE;
			
			try
			{
				tchar = (short) wpc.infile.ReadByte();
			}
			catch (System.Exception)
			{
				wpmd.status = 1;
				return Defines.FALSE;
			}
			
			wpmd.byte_length += ((int) tchar << 9);
			
			try
			{
				tchar = (short) wpc.infile.ReadByte();
			}
			catch (System.Exception)
			{
				wpmd.status = 1;
				return Defines.FALSE;
			}
			
			wpmd.byte_length += ((int) tchar << 17);
			wpmd.bytecount += 2;
		}
		
		if ((wpmd.id & Defines.ID_ODD_SIZE) != 0)
		{
			wpmd.id &= (short)~ Defines.ID_ODD_SIZE;
			wpmd.byte_length--;
		}
		
		if (wpmd.byte_length == 0 || wpmd.id == Defines.ID_WV_BITSTREAM)
		{
			wpmd.hasdata = Defines.FALSE;
			return Defines.TRUE;
		}
		
		bytes_to_read = wpmd.byte_length + (wpmd.byte_length & 1);
		
		wpmd.bytecount += bytes_to_read;
		
		if (bytes_to_read > wpc.read_buffer.Length)
		{
			int bytes_read;
			wpmd.hasdata = Defines.FALSE;
			
			while (bytes_to_read > wpc.read_buffer.Length)
			{
				try
				{
					bytes_read = wpc.infile.BaseStream.Read(wpc.read_buffer, 0, wpc.read_buffer.Length);

					if (bytes_read != wpc.read_buffer.Length)
					{
						return Defines.FALSE;
					}
				}
				catch (System.Exception)
				{
					return Defines.FALSE;
				}
				bytes_to_read -= wpc.read_buffer.Length;
			}
		}
		else
		{
			wpmd.hasdata = Defines.TRUE;
			wpmd.data = wpc.read_buffer;
		}
		
		if (bytes_to_read != 0)
		{
			int bytes_read;
			
			try
			{
				bytes_read = wpc.infile.BaseStream.Read(wpc.read_buffer, 0, (int)bytes_to_read);

				if (bytes_read != (int) bytes_to_read)
				{
					wpmd.hasdata = Defines.FALSE;
					return Defines.FALSE;
				}
			}
			catch (System.Exception)
			{
				wpmd.hasdata = Defines.FALSE;
				return Defines.FALSE;
			}
		}
		
		return Defines.TRUE;
	}
	
	internal static int process_metadata(WavpackContext wpc, WavpackMetadata wpmd)
	{
		WavpackStream wps = wpc.stream;
		
		switch (wpmd.id)
		{
			
			case Defines.ID_DUMMY: 
			{
				return Defines.TRUE;
			}
			
			
			case Defines.ID_DECORR_TERMS: 
			{
				return UnpackUtils.read_decorr_terms(wps, wpmd);
			}
			
			
			case Defines.ID_DECORR_WEIGHTS: 
			{
				return UnpackUtils.read_decorr_weights(wps, wpmd);
			}
			
			
			case Defines.ID_DECORR_SAMPLES: 
			{
				return UnpackUtils.read_decorr_samples(wps, wpmd);
			}
			
			
			case Defines.ID_ENTROPY_VARS: 
			{
				return WordsUtils.read_entropy_vars(wps, wpmd);
			}
			
			
			case Defines.ID_HYBRID_PROFILE: 
			{
				return WordsUtils.read_hybrid_profile(wps, wpmd);
			}
			
			
			case Defines.ID_FLOAT_INFO: 
			{
				return FloatUtils.read_float_info(wps, wpmd);
			}
			
			
			case Defines.ID_INT32_INFO: 
			{
				return UnpackUtils.read_int32_info(wps, wpmd);
			}
			
			
			case Defines.ID_CHANNEL_INFO: 
			{
				return UnpackUtils.read_channel_info(wpc, wpmd);
			}
			
			
			case Defines.ID_SAMPLE_RATE: 
			{
				return UnpackUtils.read_sample_rate(wpc, wpmd);
			}
			
			
			case Defines.ID_CONFIG_BLOCK: 
			{
				return UnpackUtils.read_config_info(wpc, wpmd);
			}
			
			
			case Defines.ID_WV_BITSTREAM: 
			{
				return UnpackUtils.init_wv_bitstream(wpc, wpmd);
			}
			
			
			case Defines.ID_SHAPING_WEIGHTS: 
			case Defines.ID_WVC_BITSTREAM: 
			case Defines.ID_WVX_BITSTREAM: 
			{
				return Defines.TRUE;
			}
			
			
			default: 
				{
					if ((wpmd.id & Defines.ID_OPTIONAL_DATA) != 0)
					{
						return Defines.TRUE;
					}
					else
					{
						return Defines.FALSE;
					}
				}
				break;
			
		}
	}
}