From 3f20cc46c0ead4627f6c327e0c8cfc3f8bf38c68 Mon Sep 17 00:00:00 2001
From: elie <elie>
Date: Tue, 9 Apr 2013 18:31:26 +0000
Subject: fix to REAL type decoder to handle negative REAL values correctly.
 test case added.

---
 CHANGES                        | 2 ++
 pyasn1/codec/ber/decoder.py    | 8 +++-----
 test/codec/ber/test_decoder.py | 6 ++++++
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/CHANGES b/CHANGES
index 5514a06..561dedd 100644
--- a/CHANGES
+++ b/CHANGES
@@ -13,6 +13,8 @@ Revision 0.1.7
 - Fix to REAL type encoder to force primitive encoding form encoding.
 - Fix to CHOICE decoder to handle explicitly tagged, indefinite length
   mode encoding
+- Fix to REAL type decoder to handle negative REAL values correctly. Test
+  case added.
 
 Revision 0.1.6
 --------------
diff --git a/pyasn1/codec/ber/decoder.py b/pyasn1/codec/ber/decoder.py
index 4dd00f3..be0cf49 100644
--- a/pyasn1/codec/ber/decoder.py
+++ b/pyasn1/codec/ber/decoder.py
@@ -254,9 +254,7 @@ class RealDecoder(AbstractSimpleDecoder):
         if not head:
             return self._createComponent(asn1Spec, tagSet, 0.0), tail
         fo = oct2int(head[0]); head = head[1:]
-        if fo & 0x40:  # infinite value
-            value = fo & 0x01 and '-inf' or 'inf'
-        elif fo & 0x80:  # binary enoding
+        if fo & 0x80:  # binary enoding
             n = (fo & 0x03) + 1
             if n == 4:
                 n = oct2int(head[0])
@@ -276,6 +274,8 @@ class RealDecoder(AbstractSimpleDecoder):
             if fo & 0x40:    # sign bit
                 p = -p
             value = (p, 2, e)
+        elif fo & 0x40:  # infinite value
+            value = fo & 0x01 and '-inf' or 'inf'
         elif fo & 0xc0 == 0:  # character encoding
             try:
                 if fo & 0x3 == 0x1:  # NR1
@@ -292,8 +292,6 @@ class RealDecoder(AbstractSimpleDecoder):
                 raise error.SubstrateUnderrunError(
                     'Bad character Real syntax'
                     )
-        elif fo & 0xc0 == 0x40:  # special real value
-            pass
         else:
             raise error.SubstrateUnderrunError(
                 'Unknown encoding (tag %s)' % fo
diff --git a/test/codec/ber/test_decoder.py b/test/codec/ber/test_decoder.py
index 8dd7848..36999e8 100644
--- a/test/codec/ber/test_decoder.py
+++ b/test/codec/ber/test_decoder.py
@@ -239,6 +239,12 @@ class RealDecoderTestCase(unittest.TestCase):
             ints2octs((9, 4, 128, 11, 4, 77))
         ) == (univ.Real((1101, 2, 11)), null)
 
+    def testBin3(self):
+        assert decoder.decode(
+            ints2octs((9, 3, 192, 10, 123))
+        ) == (univ.Real((-123, 2, 10)), null)
+
+
     def testPlusInf(self):
         assert decoder.decode(
             ints2octs((9, 1, 64))
-- 
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