xdrgen: Fix struct prefix for typedef types in program wrappers

[ Upstream commit bf0fe9a ]

The program templates for decoder/argument.j2 and encoder/result.j2
unconditionally add 'struct' prefix to all types. This is incorrect
when an RPC protocol specification lists a typedef'd basic type or
an enum as a procedure argument or result (e.g., NFSv2's fhandle or
stat), resulting in compiler errors when building generated C code.

Fixes: 4b132aa ("tools: Add xdrgen")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: chucklever

tools/net/sunrpc/xdrgen/generators/__init__.py

@@ -6,7 +6,7 @@
 from jinja2 import Environment, FileSystemLoader, Template
 
 from xdr_ast import _XdrAst, Specification, _RpcProgram, _XdrTypeSpecifier
-from xdr_ast import public_apis, pass_by_reference, get_header_name
+from xdr_ast import public_apis, pass_by_reference, structs, get_header_name
 from xdr_parse import get_xdr_annotate
 
 
@@ -22,6 +22,7 @@ def create_jinja2_environment(language: str, xdr_type: str) -> Environment:
             environment.globals["annotate"] = get_xdr_annotate()
             environment.globals["public_apis"] = public_apis
             environment.globals["pass_by_reference"] = pass_by_reference
+            environment.globals["structs"] = structs
             return environment
         case _:
             raise NotImplementedError("Language not supported")

tools/net/sunrpc/xdrgen/templates/C/program/decoder/argument.j2

@@ -14,7 +14,11 @@ bool {{ program }}_svc_decode_{{ argument }}(struct svc_rqst *rqstp, struct xdr_
 {% if argument == 'void' %}
 	return xdrgen_decode_void(xdr);
 {% else %}
+{% if argument in structs %}
 	struct {{ argument }} *argp = rqstp->rq_argp;
+{% else %}
+	{{ argument }} *argp = rqstp->rq_argp;
+{% endif %}
 
 	return xdrgen_decode_{{ argument }}(xdr, argp);
 {% endif %}

tools/net/sunrpc/xdrgen/templates/C/program/encoder/result.j2

@@ -14,8 +14,14 @@ bool {{ program }}_svc_encode_{{ result }}(struct svc_rqst *rqstp, struct xdr_st
 {% if result == 'void' %}
 	return xdrgen_encode_void(xdr);
 {% else %}
+{% if result in structs %}
 	struct {{ result }} *resp = rqstp->rq_resp;
 
 	return xdrgen_encode_{{ result }}(xdr, resp);
+{% else %}
+	{{ result }} *resp = rqstp->rq_resp;
+
+	return xdrgen_encode_{{ result }}(xdr, *resp);
+{% endif %}
 {% endif %}
 }