private byte[] DecompressCommon(SymbianDecompressor aDecompressor, int aSeekOffset, int aAmountToRead, int aMaximumOutputSize, out int aNumberOfInputBytesRead)
{
System.Diagnostics.Debug.WriteLine("[SIContentE32Image] DecompressCommon - START - " + base.Image.Name + " # " + System.Threading.Thread.CurrentThread.Name);
//
uint imageContentSize = iFileSize;
uint orighdrsz = ImageHeader.TotalSize;
uint remainder = imageContentSize - orighdrsz;
//
using (SymbianStreamReaderLE reader = base.ImageStream.CreateReader(SymbianStreamReaderLE.TCloseOperation.EResetPosition))
{
long codePos = Image.ContentOffsetWithinDataStream + orighdrsz + aSeekOffset;
reader.Seek(codePos);
//
byte[] input = reader.ReadBytes(aAmountToRead);
byte[] output = new byte[aMaximumOutputSize];
// The decompressor tells us how many bytes of output it really created.
int numberOfBytesCreated = aDecompressor.DecompressImage(input, output, out aNumberOfInputBytesRead);
// We can then return that to the callee.
byte[] ret = new byte[numberOfBytesCreated > 0 ? numberOfBytesCreated : 0];
if (numberOfBytesCreated > 0)
{
Array.Copy(output, ret, numberOfBytesCreated);
}
//
System.Diagnostics.Debug.WriteLine("[SIContentE32Image] DecompressCommon - END - " + base.Image.Name + " # " + System.Threading.Thread.CurrentThread.Name);
//
return(ret);
}
}
private void DecompressBytePair(SymbianDecompressor aDecompressor)
{
int inputBytesRead = 0;
//
uint imageContentSize = iFileSize;
uint orighdrsz = ImageHeader.TotalSize;
uint uncompressedSize = ImageHeader.UncompressedSize;
// First decompress the code
byte[] code = DecompressCommon(aDecompressor, 0, (int)(imageContentSize - orighdrsz), (int)uncompressedSize, out inputBytesRead);
if (code.Length < ImageHeader.CodeSize)
{
throw new Exception("E32Image bytepair decompression did not provide enough code");
}
// Now get the data
int remainder = (int)(uncompressedSize - inputBytesRead);
byte[] data = DecompressCommon(aDecompressor, inputBytesRead, remainder, (int)uncompressedSize, out inputBytesRead);
// We should have read all the decompressed data
int totalAmountOfDecompressedDataSupplied = data.Length + code.Length;
if (totalAmountOfDecompressedDataSupplied != uncompressedSize)
{
throw new Exception("E32Image bytepair decompression did not supply enough decompressed output");
}
lock ( iCodeSyncRoot )
{
iCode = new byte[uncompressedSize];
Array.Copy(code, iCode, code.Length);
Array.Copy(data, 0, iCode, code.Length, data.Length);
}
}
protected override void DoDecompress()
{
lock ( iCodeSyncRoot )
{
if (iCode == null)
{
TSymbianCompressionType type = this.CompressionType;
switch (type)
{
default:
case TSymbianCompressionType.ENone:
// NB: This has not yet been observed in reality
DecompressNone();
break;
case TSymbianCompressionType.EDeflate:
case TSymbianCompressionType.EBytePair:
{
using (SymbianDecompressor decompressor = SymbianDecompressor.NewByType(type))
{
//
switch (type)
{
case TSymbianCompressionType.EBytePair:
DecompressBytePair(decompressor);
break;
case TSymbianCompressionType.EDeflate:
DecompressDeflate(decompressor);
break;
}
}
break;
}
}
if (iCode != null)
{
if (iStream != null)
{
iStream.Dispose();
iStream = null;
}
//
iStream = new MemoryStream(iCode);
}
}
}
}
private void DecompressDeflate(SymbianDecompressor aDecompressor)
{
int inputBytesRead = 0;
//
uint imageContentSize = iFileSize;
uint orighdrsz = ImageHeader.TotalSize;
uint uncompressedSize = ImageHeader.UncompressedSize;
byte[] combinedDataAndCode = DecompressCommon(aDecompressor, 0, (int)(imageContentSize - orighdrsz), (int)uncompressedSize, out inputBytesRead);
if (combinedDataAndCode.Length != uncompressedSize)
{
throw new Exception("E32Image inflate decompression did not supply enough decompressed output");
}
lock ( iCodeSyncRoot )
{
iCode = combinedDataAndCode;
}
}
private void DoDecompressBytePair()
{
if (iContentIsPrepared == false)
{
SIHeaderROM imageHeader = ImageHeader;
base.Trace("[SymbianImageROM] DoDecompressBytePair() - START - header uncompressed rom size: {0}", imageHeader.UncompressedRomSize);
// Create new buffer and copy over rom image header
SIMemoryStream resultantDataStream = new SIMemoryStream(imageHeader.UncompressedRomSize);
int numPages = imageHeader.NumberOfPages;
uint pageTableOffset = imageHeader.RomPageIndexOffset;
uint romDataOffset = imageHeader.HeaderSizeLoader;
base.Trace("[SymbianImageROM] DoDecompressBytePair() - numPages: {0}, pageTableOffset: {1}, romDataOffset: {2}", numPages, pageTableOffset, romDataOffset);
//
SymbianDecompressor decompressor = SymbianDecompressor.NewByType(TSymbianCompressionType.EBytePair);
//
List <SRomPageInfo> pages = new List <SRomPageInfo>(numPages + 1);
for (int i = 0; i < numPages; i++)
{
// Read a page table entry
long pageOffsetWithinFile = pageTableOffset + (i * SRomPageInfo.Size);
//base.Trace( "[SymbianImageROM] DoDecompressBytePair() - page[{0:d5}] - pageOffsetWithinFile: {1}", i, pageOffsetWithinFile );
base.ImageStream.Seek(pageOffsetWithinFile, SeekOrigin.Begin);
SRomPageInfo pageInfo = SRomPageInfo.New((Stream)base.ImageStream, romDataOffset);
// Process the entry based upon the compression type
//base.Trace( "[SymbianImageROM] DoDecompressBytePair() - page[{0:d5}] - pageInfo.DataSize: {1}, pageInfo.DataStart: {2}, pageInfo.CompressionType: {3}", i, pageInfo.DataSize, pageInfo.DataStart, pageInfo.CompressionType );
base.ImageStream.Seek(pageInfo.DataStart, SeekOrigin.Begin);
if (pageInfo.CompressionType == SRomPageInfo.TSymbianCompressionType.ENoCompression)
{
// Read data - no decompression needed
//base.Trace( "[SymbianImageROM] DoDecompressBytePair() - page[{0:d5}] - PAGE NOT COMPRESSED", i );
resultantDataStream.Write(base.ImageStream, (int)pageInfo.DataSize);
}
else if (pageInfo.CompressionType == SRomPageInfo.TSymbianCompressionType.EBytePair)
{
//base.Trace( "[SymbianImageROM] DoDecompressBytePair() - page[{0:d5}] - BYTE PAIR PAGE", i );
// Read data - need to decompress it
byte[] compressedData = new byte[pageInfo.DataSize];
base.ImageStream.Read(compressedData, 0, compressedData.Length);
// Make destination buffer - which is a page big
byte[] uncompressedData = new byte[SRomPageInfo.KPageSize];
// Decompress to buffer - we're handling the page management, so we want raw decompression
int error = decompressor.DecompressRaw(compressedData, uncompressedData);
// Save it
if (error < 0)
{
base.Trace("[SymbianImageROM] DoDecompressBytePair() - page[{0:d5}] - Exception - bytepair decompression error", i);
throw new Exception("BytePair decompression error: " + error.ToString());
}
else if (error != SRomPageInfo.KPageSize)
{
base.Trace("[SymbianImageROM] DoDecompressBytePair() - page[{0:d5}] - Exception - bytepair underflow error", i);
throw new Exception("Decompressor underflow - only created " + error.ToString() + " bytes");
}
else
{
resultantDataStream.Write(uncompressedData);
}
}
else
{
base.Trace("[SymbianImageROM] DoDecompressBytePair() - page[{0:d5}] - UNSUPPORTED COMPRESSION TYPE - Exception!", i);
throw new NotSupportedException("Unsupported page compression type");
}
// Report progress
base.ReportDecompressionEvent(TDecompressionEvent.EEventDecompressionProgress, ((float)i / (float)numPages) * 100);
}
// Now we can replace the base class stream (which is just the raw compressed file data) with the new uncompressed version
base.ImageStream = resultantDataStream;
iContentIsPrepared = true;
base.Trace("[SymbianImageROM] DoDecompressBytePair() - END");
}
}
