string GetResourceName(int index, out int dataOffset)
{
long pos = nameSectionPosition + namePositions[index];
byte[] bytes;
lock (reader) {
reader.Seek(pos, SeekOrigin.Begin);
// Can't use reader.ReadString, since it's using UTF-8!
int byteLen = reader.Read7BitEncodedInt();
if (byteLen < 0)
{
throw new BadImageFormatException("Resource name has negative length");
}
bytes = new byte[byteLen];
// We must read byteLen bytes, or we have a corrupted file.
// Use a blocking read in case the stream doesn't give us back
// everything immediately.
int count = byteLen;
while (count > 0)
{
int n = reader.Read(bytes, byteLen - count, count);
if (n == 0)
{
throw new BadImageFormatException("End of stream within a resource name");
}
count -= n;
}
dataOffset = reader.ReadInt32();
if (dataOffset < 0)
{
throw new BadImageFormatException("Negative data offset");
}
}
return(Encoding.Unicode.GetString(bytes));
}
public ResourcesFile(Stream stream, bool leaveOpen = true)
{
fileStartPosition = stream.Position;
reader = new MyBinaryReader(stream, leaveOpen);
const string ResourcesHeaderCorrupted = "Resources header corrupted.";
// Read ResourceManager header
// Check for magic number
int magicNum = reader.ReadInt32();
if (magicNum != MagicNumber)
{
throw new BadImageFormatException("Not a .resources file - invalid magic number");
}
// Assuming this is ResourceManager header V1 or greater, hopefully
// after the version number there is a number of bytes to skip
// to bypass the rest of the ResMgr header. For V2 or greater, we
// use this to skip to the end of the header
int resMgrHeaderVersion = reader.ReadInt32();
int numBytesToSkip = reader.ReadInt32();
if (numBytesToSkip < 0 || resMgrHeaderVersion < 0)
{
throw new BadImageFormatException(ResourcesHeaderCorrupted);
}
if (resMgrHeaderVersion > 1)
{
reader.BaseStream.Seek(numBytesToSkip, SeekOrigin.Current);
}
else
{
// We don't care about numBytesToSkip; read the rest of the header
// readerType:
reader.ReadString();
// resourceSetType:
reader.ReadString();
}
// Read RuntimeResourceSet header
// Do file version check
version = reader.ReadInt32();
if (version != ResourceSetVersion && version != 1)
{
throw new BadImageFormatException($"Unsupported resource set version: {version}");
}
numResources = reader.ReadInt32();
if (numResources < 0)
{
throw new BadImageFormatException(ResourcesHeaderCorrupted);
}
// Read type positions into type positions array.
// But delay initialize the type table.
int numTypes = reader.ReadInt32();
if (numTypes < 0)
{
throw new BadImageFormatException(ResourcesHeaderCorrupted);
}
typeTable = new string[numTypes];
for (int i = 0; i < numTypes; i++)
{
typeTable[i] = reader.ReadString();
}
// Prepare to read in the array of name hashes
// Note that the name hashes array is aligned to 8 bytes so
// we can use pointers into it on 64 bit machines. (4 bytes
// may be sufficient, but let's plan for the future)
// Skip over alignment stuff. All public .resources files
// should be aligned No need to verify the byte values.
long pos = reader.BaseStream.Position - fileStartPosition;
int alignBytes = unchecked ((int)pos) & 7;
if (alignBytes != 0)
{
for (int i = 0; i < 8 - alignBytes; i++)
{
reader.ReadByte();
}
}
// Skip over the array of name hashes
try
{
reader.Seek(checked (4 * numResources), SeekOrigin.Current);
}
catch (OverflowException)
{
throw new BadImageFormatException(ResourcesHeaderCorrupted);
}
// Read in the array of relative positions for all the names.
namePositions = new int[numResources];
for (int i = 0; i < numResources; i++)
{
int namePosition = reader.ReadInt32();
if (namePosition < 0)
{
throw new BadImageFormatException(ResourcesHeaderCorrupted);
}
namePositions[i] = namePosition;
}
// Read location of data section.
int dataSectionOffset = reader.ReadInt32();
if (dataSectionOffset < 0)
{
throw new BadImageFormatException(ResourcesHeaderCorrupted);
}
// Store current location as start of name section
nameSectionPosition = reader.BaseStream.Position;
dataSectionPosition = fileStartPosition + dataSectionOffset;
// _nameSectionOffset should be <= _dataSectionOffset; if not, it's corrupt
if (dataSectionPosition < nameSectionPosition)
{
throw new BadImageFormatException(ResourcesHeaderCorrupted);
}
}