Release notes, test case and some minor decode fixes

(allow only 32 bit values when decoding).

3 files changed, 64 insertions, 11 deletions

diff --git a/lib/snmp/doc/src/notes.xml b/lib/snmp/doc/src/notes.xml
index c507965cd8..105a977d92 100644
--- a/lib/snmp/doc/src/notes.xml
+++ b/lib/snmp/doc/src/notes.xml
@@ -44,6 +44,15 @@
 -->
       <list type="bulleted">
         <item>
+          <p>Fixed endode/decode of values of type <c>Counter32</c>. </p>
+	  <p>This type (<c>Counter32</c>) is an unsigned integer 32, 
+	  but is actually encoded as an signed integer 32. 
+	  The encode/decode functions however, treated it as if it was 
+	  encodeded as an unsigned integer 32. </p>
+	  <p>Own Id: OTP-9022</p>
+	</item>
+
+        <item>
           <p>[agent] Added support for sending traps to IPv6 targets. </p>
 	  <p>See the 
 	  <seealso marker="snmp_agent_config_files#target_addr">target address config file</seealso>, 
diff --git a/lib/snmp/src/misc/snmp_pdus.erl b/lib/snmp/src/misc/snmp_pdus.erl
index 9c273bc0e0..213d0226b1 100644
--- a/lib/snmp/src/misc/snmp_pdus.erl
+++ b/lib/snmp/src/misc/snmp_pdus.erl
@@ -268,14 +268,6 @@ dec_value([4 | Bytes]) ->
 dec_value([64 | Bytes]) -> 
     {Value, Rest} = dec_oct_str_notag(Bytes),
     {{'IpAddress', Value}, Rest};
-%% dec_value([65 | Bytes]) ->
-%%     {Value, Rest} = dec_integer_notag(Bytes),
-%%     if 
-%% 	(Value >= 0) andalso (Value =< 4294967295) ->
-%% 	    {{'Counter32', Value}, Rest};
-%% 	true ->
-%% 	    exit({error, {bad_counter32, Value}})
-%%     end;
 dec_value([65 | Bytes]) ->
     %% Counter32 is an unsigned 32 but is actually encoded as 
     %% a signed integer 32 (INTEGER).
@@ -284,12 +276,13 @@ dec_value([65 | Bytes]) ->
 	if
 	    (Value >= 0) andalso (Value =< 16#ffffffff) ->
 		%% We accept value above 16#7fffffff
+		%% in order to be backward bug-compatible
 		Value;
 	    (Value < 0) ->
 		16#ffffffff + Value + 1;
 	    true ->
 		exit({error, {bad_counter32, Value}})	end,
-    {{'Counter64', Value2}, Rest};
+    {{'Counter32', Value2}, Rest};
 dec_value([66 | Bytes]) ->
     {Value, Rest} = dec_integer_notag(Bytes),
     if 
diff --git a/lib/snmp/test/snmp_pdus_test.erl b/lib/snmp/test/snmp_pdus_test.erl
index ef510ad62e..197797c816 100644
--- a/lib/snmp/test/snmp_pdus_test.erl
+++ b/lib/snmp/test/snmp_pdus_test.erl
@@ -38,6 +38,8 @@
 	
 	 otp7575/1,
 	 otp8563/1, 
+	 otp9022/1, 
+
          init_per_testcase/2, end_per_testcase/2
 	]).
 
@@ -75,7 +77,7 @@ all() ->
 [{group, tickets}].
 
 groups() -> 
-    [{tickets, [], [otp7575, otp8563]}].
+    [{tickets, [], [otp7575, otp8563, otp9022]}].
 
 init_per_group(_GroupName, Config) ->
 	Config.
@@ -169,7 +171,56 @@ otp8563(Config) when is_list(Config) ->
 	Unexpected7 ->
 	    exit({unexpected_encode_result, Unexpected7, Val7})
     end,
-    
+
+    ok.
+
+
+otp9022(suite) -> [];
+otp9022(doc) -> ["OTP-9022"];
+otp9022(Config) when is_list(Config) ->
+    Val1 = 16#7fffffff,
+    io:format("try encode and decode ~w~n", [Val1]),
+    Enc1 = snmp_pdus:enc_value('Counter32', Val1), 
+    {{'Counter32', Val1}, []} = snmp_pdus:dec_value(Enc1), 
+
+    Val2 = Val1 + 1,
+    io:format("try encode and decode ~w~n", [Val2]),
+    Enc2 = snmp_pdus:enc_value('Counter32', Val2), 
+    {{'Counter32', Val2}, []} = snmp_pdus:dec_value(Enc2), 
+
+    Val3 = Val2 + 1,
+    io:format("try encode and decode ~w~n", [Val3]),
+    Enc3 = snmp_pdus:enc_value('Counter32', Val3), 
+    {{'Counter32', Val3}, []} = snmp_pdus:dec_value(Enc3), 
+
+    Val4 = 16#fffffffe,
+    io:format("try encode and decode ~w~n", [Val4]),
+    Enc4 = snmp_pdus:enc_value('Counter32', Val4), 
+    {{'Counter32', Val4}, []} = snmp_pdus:dec_value(Enc4), 
+
+    Val5 = Val4 + 1,
+    io:format("try encode and decode ~w~n", [Val5]),
+    Enc5 = snmp_pdus:enc_value('Counter32', Val5), 
+    {{'Counter32', Val5}, []} = snmp_pdus:dec_value(Enc5), 
+
+    Val6 = 16#ffffffff + 1, 
+    io:format("try and fail to encode ~w~n", [Val6]),
+    case (catch snmp_pdus:enc_value('Counter32', Val6)) of
+	{'EXIT', {error, {bad_counter32, Val6}}} ->
+	    ok;
+	Unexpected6 ->
+	    exit({unexpected_encode_result, Unexpected6, Val6})
+    end,
+
+    Val7 = -1, 
+    io:format("try and fail to encode ~w~n", [Val7]),
+    case (catch snmp_pdus:enc_value('Counter32', Val7)) of
+	{'EXIT', {error, {bad_counter32, Val7}}} ->
+	    ok;
+	Unexpected7 ->
+	    exit({unexpected_encode_result, Unexpected7, Val7})
+    end,
+
     ok.