Update lz4.py

lz4.py

@@ -1,5 +1,36 @@
 import base64,Buffer,errorHandler,os,pyrbxm,struct,sys,requests,robloxapi
 
 def decompress(lz4data):
-    inputStream = Buffer.new(lz4data)
+    inputStream=Buffer.new(lz4data)
+    compressedLen=struct.unpack("<I4",inputStream.read(4))
+    decompressedLen=struct.unpack("<I4",inputStream.read(4))
+    reserved=struct.unpack("<I4",inputStream.read(4))
+    if (reserved!=0):
+        errorHandler.error('Provided Chunk is not LZ4 data!')
+    ##endif
+    if (compressedLen==0):
+        return inputStream.read(decompressedLen)
+    ##endif
+    outputStream=Buffer.new("")
+    while (outputStream.Length<decompressedLen):
+        token=ord(inputStream.read())
+        litLen=token >> 4
+        matLen=(token & 15) + 4
+        if (litLen>=15):
+            ifinish=False
+            while (ifinish!=True):
+                nextByte=ord(inputStream.read())
+                litLen=litLen+nextByte
+                if (nextByte!=0xFF):
+                    ifinish=True
+                ##endif
+                literal = inputStream.read(litLen)
+                outputStream.append(literal)
+                outputStream.toEnd()
+                if (outputStream.Length<decompressedLen):
+                    offset=struct.unpack("<I2",inputStream.read(2))
+                ##endif
+            ##end
+        ##endif
+    ##end
 ##end