Improved exception handing. Added some XXX comments.

diff --git a/Demo/rpc/rpc.py b/Demo/rpc/rpc.py
index 6d3fade19918b23e2a869757d65e2d5035462965..4fbc795765138ec81ba7fb3ea2a617b367d7ac65 100644 (file)
--- a/Demo/rpc/rpc.py
+++ b/Demo/rpc/rpc.py
@@ -1,5 +1,11 @@
 # Implement (a subset of) Sun RPC, version 2 -- RFC1057.
 
+# XXX There should be separate exceptions for the various reasons why
+# XXX an RPC can fail, rather than using RuntimeError for everything
+
+# XXX The UDP version of the protocol resends requests when it does
+# XXX not receive a timely reply -- use only for idempotent calls!
+
 import xdr
 import socket
 import os
@@ -80,24 +86,32 @@ class Unpacker(xdr.Unpacker):
                xid = self.unpack_uint()
                mtype = self.unpack_enum()
                if mtype <> REPLY:
-                       raise RuntimeError, 'no REPLY but ' + str(mtype)
+                       raise RuntimeError, 'no REPLY but ' + `mtype`
                stat = self.unpack_enum()
+               if stat == MSG_DENIED:
+                       stat = self.unpack_enum()
+                       if stat == RPC_MISMATCH:
+                               low = self.unpack_uint()
+                               high = self.unpack_uint()
+                               raise RuntimeError, \
+                                 'MSG_DENIED: RPC_MISMATCH: ' + `low, high`
+                       if stat == AUTH_ERROR:
+                               stat = self.unpack_uint()
+                               raise RuntimeError, \
+                                       'MSG_DENIED: AUTH_ERROR: ' + `stat`
+                       raise RuntimeError, 'MSG_DENIED: ' + `stat`
                if stat <> MSG_ACCEPTED:
-                       if stat == MSG_DENIED:
-                               stat = self.unpack_enum()
-                               if stat == RPC_MISMATCH:
-                                       low = self.unpack_uint()
-                                       high = self.unpack_uint()
-                                       raise 'RPC_MISMATCH', (low, high)
-                               if stat == AUTH_ERROR:
-                                       stat = self.unpack_uint()
-                                       raise 'AUTH_ERROR', str(stat)
-                               raise 'MSG_REJECTED', str(stat)
-                       raise RuntimeError, 'no MSG_ACCEPTED but ' + str(stat)
+                       raise RuntimeError, \
+                         'Neither MSG_DENIED nor MSG_ACCEPTED: ' + `stat`
                verf = self.unpack_auth()
                stat = self.unpack_enum()
+               if stat == PROG_MISMATCH:
+                       low = self.unpack_uint()
+                       high = self.unpack_uint()
+                       raise RuntimeError, \
+                               'call failed: PROG_MISMATCH: ' + `low, high`
                if stat <> SUCCESS:
-                       raise RuntimeError, 'no SUCCESS but ' + str(stat)
+                       raise RuntimeError, 'call failed: ' + `stat`
                return xid, verf
                # Caller must get procedure-specific part of reply
 
@@ -229,7 +243,6 @@ class RawTCPClient(Client):
 
 
 # Raw UDP-based client
-# XXX This class does not recover from missed/duplicated packets!
 
 class RawUDPClient(Client):