[PATCH] xdrgen: improve error reporting for invalid void declarations

[Khushal Chitturi <kc9282016@gmail.com>]

RFC 4506 defines void as a zero-length type that may appear only as
union arms or as program argument/result types. It cannot be declared
with an identifier, so constructs like "typedef void temp;" are not
valid XDR.

Previously, xdrgen raised a NotImplementedError when it encountered a
void declaration in a typedef. Which was misleading, as the problem is an
invalid RPC specification rather than missing functionality in xdrgen.

This patch replaces the NotImplementedError for _XdrVoid in typedef
handling with a clearer ValueError that specifies incorrect use of void
in the XDR input, making it clear that the issue lies in the RPC
specification being parsed.

Signed-off-by: Khushal Chitturi <kc9282016@gmail.com>
---
 tools/net/sunrpc/xdrgen/generators/typedef.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/net/sunrpc/xdrgen/generators/typedef.py b/tools/net/sunrpc/xdrgen/generators/typedef.py
index fab72e9d6915..75e3a40e14e1 100644
--- a/tools/net/sunrpc/xdrgen/generators/typedef.py
+++ b/tools/net/sunrpc/xdrgen/generators/typedef.py
@@ -58,7 +58,7 @@ def emit_typedef_declaration(environment: Environment, node: _XdrDeclaration) ->
     elif isinstance(node, _XdrOptionalData):
         raise NotImplementedError("<optional_data> typedef not yet implemented")
     elif isinstance(node, _XdrVoid):
-        raise NotImplementedError("<void> typedef not yet implemented")
+        raise ValueError("invalid void usage in RPC Specification")
     else:
         raise NotImplementedError("typedef: type not recognized")
 
@@ -104,7 +104,7 @@ def emit_type_definition(environment: Environment, node: _XdrDeclaration) -> Non
     elif isinstance(node, _XdrOptionalData):
         raise NotImplementedError("<optional_data> typedef not yet implemented")
     elif isinstance(node, _XdrVoid):
-        raise NotImplementedError("<void> typedef not yet implemented")
+        raise ValueError("invalid void usage in RPC Specification")
     else:
         raise NotImplementedError("typedef: type not recognized")
 
@@ -165,7 +165,7 @@ def emit_typedef_decoder(environment: Environment, node: _XdrDeclaration) -> Non
     elif isinstance(node, _XdrOptionalData):
         raise NotImplementedError("<optional_data> typedef not yet implemented")
     elif isinstance(node, _XdrVoid):
-        raise NotImplementedError("<void> typedef not yet implemented")
+        raise ValueError("invalid void usage in RPC Specification")
     else:
         raise NotImplementedError("typedef: type not recognized")
 
@@ -225,7 +225,7 @@ def emit_typedef_encoder(environment: Environment, node: _XdrDeclaration) -> Non
     elif isinstance(node, _XdrOptionalData):
         raise NotImplementedError("<optional_data> typedef not yet implemented")
     elif isinstance(node, _XdrVoid):
-        raise NotImplementedError("<void> typedef not yet implemented")
+        raise ValueError("invalid void usage in RPC Specification")
     else:
         raise NotImplementedError("typedef: type not recognized")
 
-- 
2.51.2