Rewrote _{read,write}_{short,long} to use the newly revamped struct

module.  (Small problem: struct.pack() won't deal with the Python long
ints returned by struct.unpack() for the 'L' format.  Worked around
that for now.)

diff --git a/Lib/aifc.py b/Lib/aifc.py
index 0c2b10bf3585c9554f2a60709576b12a7a7f091b..2e4b19caa74d717a431cd7864a86c9851b2a67f5 100644 (file)
--- a/Lib/aifc.py
+++ b/Lib/aifc.py
@@ -133,6 +133,7 @@
 # changed by calling aiff() or aifc() before the first writeframes or
 # writeframesraw.
 
+import struct
 import __builtin__
 try:
        import CL
@@ -147,35 +148,22 @@ _skiplist = 'COMT', 'INST', 'MIDI', 'AESD', \
          'APPL', 'NAME', 'AUTH', '(c) ', 'ANNO'
 
 def _read_long(file):
-       x = 0L
-       for i in range(4):
-               byte = file.read(1)
-               if byte == '':
-                       raise EOFError
-               x = x*256 + ord(byte)
-       if x >= 0x80000000L:
-               x = x - 0x100000000L
-       return int(x)
+       try:
+               return struct.unpack('>l', file.read(4))[0]
+       except struct.error:
+               raise EOFError
 
 def _read_ulong(file):
-       x = 0L
-       for i in range(4):
-               byte = file.read(1)
-               if byte == '':
-                       raise EOFError
-               x = x*256 + ord(byte)
-       return x
+       try:
+               return struct.unpack('>L', file.read(4))[0]
+       except struct.error:
+               raise EOFError
 
 def _read_short(file):
-       x = 0
-       for i in range(2):
-               byte = file.read(1)
-               if byte == '':
-                       raise EOFError
-               x = x*256 + ord(byte)
-       if x >= 0x8000:
-               x = x - 0x10000
-       return x
+       try:
+               return struct.unpack('>h', file.read(2))[0]
+       except struct.error:
+               raise EOFError
 
 def _read_string(file):
        length = ord(file.read(1))
@@ -208,20 +196,12 @@ def _read_float(f): # 10 bytes
        return sign * f
 
 def _write_short(f, x):
-       d, m = divmod(x, 256)
-       f.write(chr(d))
-       f.write(chr(m))
+       f.write(struct.pack('>h', x))
 
 def _write_long(f, x):
-       if x < 0:
-               x = x + 0x100000000L
-       data = []
-       for i in range(4):
-               d, m = divmod(x, 256)
-               data.insert(0, m)
-               x = d
-       for i in range(4):
-               f.write(chr(int(data[i])))
+       if x >= 1L<<31:
+               x = x - (1L<<32)
+       f.write(struct.pack('>l', x))
 
 def _write_string(f, s):
        f.write(chr(len(s)))
@@ -1013,3 +993,30 @@ def open(f, mode):
                raise Error, "mode must be 'r' or 'w'"
 
 openfp = open # B/W compatibility
+
+if __name__ == '__main__':
+       import sys
+       if not sys.argv[1:]:
+               sys.argv.append('/usr/demos/data/audio/bach.aiff')
+       fn = sys.argv[1]
+       f = open(fn, 'r')
+       print "Reading", fn
+       print "nchannels =", f.getnchannels()
+       print "nframes   =", f.getnframes()
+       print "sampwidth =", f.getsampwidth()
+       print "framerate =", f.getframerate()
+       print "comptype  =", f.getcomptype()
+       print "compname  =", f.getcompname()
+       if sys.argv[2:]:
+               gn = sys.argv[2]
+               print "Writing", gn
+               g = open(gn, 'w')
+               g.setparams(f.getparams())
+               while 1:
+                       data = f.readframes(1024)
+                       if not data:
+                               break
+                       g.writeframes(data)
+               g.close()
+               f.close()
+               print "Done."