Use binascii module (resulting in a 60-fold speedup:-)

Lib/base64.py

@@ -2,95 +2,33 @@
 # version).
 
 # Parameters set by RFX-XXXX.
+#
+# Modified 04-Oct-95 by Jack to use binascii module
+
+import binascii
+
 MAXLINESIZE = 76 # Excluding the CRLF
-INVAR = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
-PAD = '='
-
-# Check that I typed that string correctly...
-if len(INVAR) <> 64: raise RuntimeError, 'wrong INVAR string!?!?'
-
-# Compute the inverse table, for decode().
-inverse = {}
-for i in range(64): inverse[INVAR[i]] = i
-del i
-inverse[PAD] = 0
+MAXBINSIZE = (MAXLINESIZE/4)*3
 
 # Encode a file.
 def encode(input, output):
-	line = ''
-	BUFSIZE = 8192
-	leftover = ''
 	while 1:
-		s = input.read(BUFSIZE)
+		s = input.read(MAXBINSIZE)
 		if not s: break
-		s = leftover + s
-		i = 0
-		while i+3 <= len(s):
-			quad = makequad(s[i:i+3])
-			i = i+3
-			if len(line) + 4 > MAXLINESIZE:
-				output.write(line + '\n')
-				line = ''
-			line = line + quad
-		leftover = s[i:]
-	if leftover:
-		quad = makeshortquad(leftover)
-		if len(line) + 4 > MAXLINESIZE:
-			output.write(line + '\n')
-			line = ''
-		line = line + quad
-	if line:
-		output.write(line + '\n')
-
-def makequad(s): # Return the quad for a 3 character string
-	x = ord(s[0])*0x10000 + ord(s[1])*0x100 + ord(s[2])
-	x, c4 = divmod(x, 64)
-	x, c3 = divmod(x, 64)
-	c1, c2 = divmod(x, 64)
-	return INVAR[c1] + INVAR[c2] +INVAR[c3] + INVAR[c4]
-
-def makeshortquad(s): # Return the quad value for a 1 or 2 character string
-	n = len(s)
-	while len(s) < 3:
-		s = s + '\0'
-	quad = makequad(s)
-	if n == 2:
-		quad = quad[:3] + PAD
-	elif n == 1:
-		quad = quad[:2] + 2*PAD
-	return quad
+		while len(s) < MAXBINSIZE:
+		    ns = input.read(MAXBINSIZE-len(s))
+		    if not ns: break
+		    s = s + ns
+		line = binascii.b2a_base64(s)
+		output.write(line)
 
 # Decode a file.
 def decode(input, output):
-	BUFSIZE = 8192
-	bits, n, bytes, prev = 0, 0, '', ''
 	while 1:
 		line = input.readline()
 		if not line: break
-		for c in line:
-			if inverse.has_key(c):
-				bits = bits*64 + inverse[c]
-				n = n+6
-				if n == 24:
-					triplet = decodequad(bits)
-					if c == PAD:
-						if prev == PAD:
-							triplet = triplet[:1]
-						else:
-							triplet = triplet[:2]
-					bits, n = 0, 0
-					bytes = bytes + triplet
-					if len(bytes) > BUFSIZE:
-						output.write(bytes[:BUFSIZE])
-						bytes = bytes[BUFSIZE:]
-				prev = c
-	if bytes:
-		output.write(bytes)
-
-def decodequad(bits): # Turn 24 bits into 3 characters
-	bits, c3 = divmod(bits, 256)
-	c1, c2 = divmod(bits, 256)
-	return chr(c1) + chr(c2) + chr(c3)
+		s = binascii.a2b_base64(line)
+		output.write(s)
 
 def encodestring(s):
 	import StringIO