/// <summary>
/// Reads a <see cref="GgpkFreeRecord"/> from the given <see cref="BinaryReader"/>.
/// </summary>
/// <param name="marker">The <see cref="GgpkRecordMarker"/> of the record.</param>
/// <param name="reader">The <see cref="BinaryReader"/> that shall be read.</param>
/// <returns>A <see cref="GgpkFreeRecord"/>.</returns>
public static GgpkFreeRecord From(GgpkRecordMarker marker, BinaryReader reader)
{
GgpkFreeRecord record = new GgpkFreeRecord
{
NextFreeRecordOffset = reader.ReadUInt64(),
DataLength = marker.Length - GgpkRecordMarker.Size
};
// Skip free space, move to position of next record
reader.BaseStream.Seek(record.DataLength - Size, SeekOrigin.Current);
return(record);
}
/// <summary>
/// Reads a <see cref="GgpkFileRecord"/> from the given <see cref="BinaryReader"/>.
/// </summary>
/// <param name="marker">The <see cref="GgpkRecordMarker"/> of the record.</param>
/// <param name="reader">The <see cref="BinaryReader"/> that shall be read.</param>
/// <returns>A <see cref="GgpkFileRecord"/>.</returns>
public static GgpkFileRecord From(GgpkRecordMarker marker, BinaryReader reader)
{
uint fileNameLength = reader.ReadUInt32();
string hash = Convert.ToBase64String(reader.ReadBytes(32));
string fileName = Encoding.Unicode.GetString(reader.ReadBytes((int)fileNameLength * 2)).TrimEnd('\0');
ulong fileOffset = (ulong)reader.BaseStream.Position;
ulong fileRecordHeaderLength = fileOffset - marker.Offset;
ulong fileLength = marker.Length - fileRecordHeaderLength;
GgpkFileRecord record = new GgpkFileRecord
{
FileName = fileName,
Hash = hash,
FileOffset = fileOffset,
FileLength = fileLength
};
// Skip actual file data, move to position of next record
reader.BaseStream.Seek((long)record.FileLength, SeekOrigin.Current);
return(record);
}
/// <summary>
/// Reads the given ggpk archive <paramref name="stream"/> and returns all records.
/// </summary>
/// <param name="stream">The ggpk <see cref="Stream"/>.</param>
/// <returns>All records read from the <see cref="Stream"/>.</returns>
/// <exception cref="ArgumentNullException"><c>stream</c> is <c>null</c>.</exception>
/// <exception cref="GgpkException">Error while reading the archive.</exception>
public static IEnumerable <GgpkRecord> From(Stream stream)
{
if (stream is null)
{
throw new ArgumentNullException(nameof(stream));
}
List <GgpkRecord> records = new List <GgpkRecord>();
using (BinaryReader ggpkStreamReader = new BinaryReader(stream))
{
try
{
while (ggpkStreamReader.BaseStream.Position < ggpkStreamReader.BaseStream.Length)
{
GgpkRecordMarker recordMarker = GgpkRecordMarker.From(ggpkStreamReader);
GgpkRecord currentRecord = null;
if (recordMarker.Offset + recordMarker.Length > (ulong)ggpkStreamReader.BaseStream.Length)
{
throw new InvalidDataException($"Invalid record length {recordMarker.Length} at offset {recordMarker.Offset}");
}
switch (recordMarker.Type)
{
case "GGPK":
currentRecord = GgpkMainRecord.From(ggpkStreamReader);
break;
case "FREE":
currentRecord = GgpkFreeRecord.From(recordMarker, ggpkStreamReader);
break;
case "FILE":
currentRecord = GgpkFileRecord.From(recordMarker, ggpkStreamReader);
break;
case "PDIR":
currentRecord = GgpkDirectoryRecord.From(ggpkStreamReader);
break;
default:
throw new InvalidDataException($"Unknown record type {recordMarker.Type} at offset {recordMarker.Offset}");
}
currentRecord.Offset = recordMarker.Offset;
currentRecord.Length = recordMarker.Length;
records.Add(currentRecord);
}
}
catch (Exception ex)
{
throw new GgpkException($"Error while parsing the ggpk archive file", ex)
{
Offset = ggpkStreamReader.BaseStream.Position
};
}
}
return(records);
}