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Use CHD models from library

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This commit is contained in:
Matt Nadareski
2024-10-20 00:03:29 -04:00
parent 4d5ac92125
commit ab93ba406c
6 changed files with 158 additions and 394 deletions
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65
SabreTools.FileTypes/CHD/CHDFile.cs
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@@ -13,22 +13,17 @@ namespace SabreTools.FileTypes.CHD
{
#region Private instance variables
// Common header fields
protected char[] tag = new char[8]; // 'MComprHD'
protected uint length; // length of header (including tag and length fields)
protected uint version; // drive format version
protected const string Signature = "MComprHD";
/// <summary>
/// Model representing the correct CHD header
/// </summary>
protected Models.CHD.Header? _header;
#endregion
#region Constructors
/// <summary>
/// Empty constructor
/// </summary>
public CHDFile()
{
}
/// <summary>
/// Create a new CHDFile from an input file
/// </summary>
@@ -47,13 +42,9 @@ namespace SabreTools.FileTypes.CHD
{
try
{
// Read the standard CHD headers
(char[] tag, uint length, uint version) = GetHeaderValues(chdstream);
chdstream.SeekIfPossible(); // Seek back to start
// Validate that this is actually a valid CHD
uint validatedVersion = ValidateHeader(tag, length, version);
if (validatedVersion == 0)
uint version = ValidateHeader(chdstream);
if (version == 0)
return null;
// Read and return the current CHD
@@ -78,40 +69,26 @@ namespace SabreTools.FileTypes.CHD
#region Header Parsing
/// <summary>
/// Get the generic header values of a CHD, if possible
/// </summary>
/// <param name="stream"></param>
/// <returns></returns>
private static (char[] tag, uint length, uint version) GetHeaderValues(Stream stream)
{
char[] parsedTag = new char[8];
uint parsedLength = 0;
uint parsedVersion = 0;
#if NET20 || NET35 || NET40
using (BinaryReader br = new(stream, Encoding.Default))
#else
using (BinaryReader br = new(stream, Encoding.Default, true))
#endif
{
parsedTag = br.ReadChars(8);
parsedLength = br.ReadUInt32BigEndian();
parsedVersion = br.ReadUInt32BigEndian();
}
return (parsedTag, parsedLength, parsedVersion);
}
/// <summary>
/// Validate the header values
/// </summary>
/// <returns>Matching version, 0 if none</returns>
private static uint ValidateHeader(char[] tag, uint length, uint version)
private static uint ValidateHeader(Stream stream)
{
if (!string.Equals(new string(tag), "MComprHD", StringComparison.Ordinal))
// Read the header values
byte[] tagBytes = stream.ReadBytes(8);
string tag = Encoding.ASCII.GetString(tagBytes);
uint length = stream.ReadUInt32BigEndian();
uint version = stream.ReadUInt32BigEndian();
// Seek back to start
stream.SeekIfPossible();
// Check the signature
if (!string.Equals(tag, Signature, StringComparison.Ordinal))
return 0;
// Match the version to header length
return version switch
{
1 => length == CHDFileV1.HeaderSize ? version : 0,