11 files changed, 1601 insertions, 0 deletions
diff --git a/tools/net/sunrpc/xdrgen/generators/__init__.py b/tools/net/sunrpc/xdrgen/generators/__init__.py
new file mode 100644
index 000000000000..b98574a36a4a
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/__init__.py
@@ -0,0 +1,117 @@
+# SPDX-License-Identifier: GPL-2.0
+
+"""Define a base code generator class"""
+
+import sys
+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_parse import get_xdr_annotate
+
+
+def create_jinja2_environment(language: str, xdr_type: str) -> Environment:
+    """Open a set of templates based on output language"""
+    match language:
+        case "C":
+            environment = Environment(
+                loader=FileSystemLoader(sys.path[0] + "/templates/C/" + xdr_type + "/"),
+                trim_blocks=True,
+                lstrip_blocks=True,
+            )
+            environment.globals["annotate"] = get_xdr_annotate()
+            environment.globals["public_apis"] = public_apis
+            environment.globals["pass_by_reference"] = pass_by_reference
+            return environment
+        case _:
+            raise NotImplementedError("Language not supported")
+
+
+def get_jinja2_template(
+    environment: Environment, template_type: str, template_name: str
+) -> Template:
+    """Retrieve a Jinja2 template for emitting source code"""
+    return environment.get_template(template_type + "/" + template_name + ".j2")
+
+
+def find_xdr_program_name(root: Specification) -> str:
+    """Retrieve the RPC program name from an abstract syntax tree"""
+    raw_name = get_header_name()
+    if raw_name != "none":
+        return raw_name.lower()
+    for definition in root.definitions:
+        if isinstance(definition.value, _RpcProgram):
+            raw_name = definition.value.name
+            return raw_name.lower().removesuffix("_program").removesuffix("_prog")
+    return "noprog"
+
+
+def header_guard_infix(filename: str) -> str:
+    """Extract the header guard infix from the specification filename"""
+    basename = filename.split("/")[-1]
+    program = basename.replace(".x", "")
+    return program.upper()
+
+
+def kernel_c_type(spec: _XdrTypeSpecifier) -> str:
+    """Return name of C type"""
+    builtin_native_c_type = {
+        "bool": "bool",
+        "int": "s32",
+        "unsigned_int": "u32",
+        "long": "s32",
+        "unsigned_long": "u32",
+        "hyper": "s64",
+        "unsigned_hyper": "u64",
+    }
+    if spec.type_name in builtin_native_c_type:
+        return builtin_native_c_type[spec.type_name]
+    return spec.type_name
+
+
+class Boilerplate:
+    """Base class to generate boilerplate for source files"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        raise NotImplementedError("No language support defined")
+
+    def emit_declaration(self, filename: str, root: Specification) -> None:
+        """Emit declaration header boilerplate"""
+        raise NotImplementedError("Header boilerplate generation not supported")
+
+    def emit_definition(self, filename: str, root: Specification) -> None:
+        """Emit definition header boilerplate"""
+        raise NotImplementedError("Header boilerplate generation not supported")
+
+    def emit_source(self, filename: str, root: Specification) -> None:
+        """Emit generic source code for this XDR type"""
+        raise NotImplementedError("Source boilerplate generation not supported")
+
+
+class SourceGenerator:
+    """Base class to generate header and source code for XDR types"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        raise NotImplementedError("No language support defined")
+
+    def emit_declaration(self, node: _XdrAst) -> None:
+        """Emit one function declaration for this XDR type"""
+        raise NotImplementedError("Declaration generation not supported")
+
+    def emit_decoder(self, node: _XdrAst) -> None:
+        """Emit one decoder function for this XDR type"""
+        raise NotImplementedError("Decoder generation not supported")
+
+    def emit_definition(self, node: _XdrAst) -> None:
+        """Emit one definition for this XDR type"""
+        raise NotImplementedError("Definition generation not supported")
+
+    def emit_encoder(self, node: _XdrAst) -> None:
+        """Emit one encoder function for this XDR type"""
+        raise NotImplementedError("Encoder generation not supported")
+
+    def emit_maxsize(self, node: _XdrAst) -> None:
+        """Emit one maxsize macro for this XDR type"""
+        raise NotImplementedError("Maxsize macro generation not supported")
diff --git a/tools/net/sunrpc/xdrgen/generators/constant.py b/tools/net/sunrpc/xdrgen/generators/constant.py
new file mode 100644
index 000000000000..f2339caf0953
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/constant.py
@@ -0,0 +1,20 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate code to handle XDR constants"""
+
+from generators import SourceGenerator, create_jinja2_environment
+from xdr_ast import _XdrConstant
+
+class XdrConstantGenerator(SourceGenerator):
+    """Generate source code for XDR constants"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "constants")
+        self.peer = peer
+
+    def emit_definition(self, node: _XdrConstant) -> None:
+        """Emit one definition for a constant"""
+        template = self.environment.get_template("definition.j2")
+        print(template.render(name=node.name, value=node.value))
diff --git a/tools/net/sunrpc/xdrgen/generators/enum.py b/tools/net/sunrpc/xdrgen/generators/enum.py
new file mode 100644
index 000000000000..e62f715d3996
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/enum.py
@@ -0,0 +1,64 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate code to handle XDR enum types"""
+
+from generators import SourceGenerator, create_jinja2_environment
+from xdr_ast import _XdrEnum, public_apis, big_endian, get_header_name
+
+
+class XdrEnumGenerator(SourceGenerator):
+    """Generate source code for XDR enum types"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "enum")
+        self.peer = peer
+
+    def emit_declaration(self, node: _XdrEnum) -> None:
+        """Emit one declaration pair for an XDR enum type"""
+        if node.name in public_apis:
+            template = self.environment.get_template("declaration/enum.j2")
+            print(template.render(name=node.name))
+
+    def emit_definition(self, node: _XdrEnum) -> None:
+        """Emit one definition for an XDR enum type"""
+        template = self.environment.get_template("definition/open.j2")
+        print(template.render(name=node.name))
+
+        template = self.environment.get_template("definition/enumerator.j2")
+        for enumerator in node.enumerators:
+            print(template.render(name=enumerator.name, value=enumerator.value))
+
+        if node.name in big_endian:
+            template = self.environment.get_template("definition/close_be.j2")
+        else:
+            template = self.environment.get_template("definition/close.j2")
+        print(template.render(name=node.name))
+
+    def emit_decoder(self, node: _XdrEnum) -> None:
+        """Emit one decoder function for an XDR enum type"""
+        if node.name in big_endian:
+            template = self.environment.get_template("decoder/enum_be.j2")
+        else:
+            template = self.environment.get_template("decoder/enum.j2")
+        print(template.render(name=node.name))
+
+    def emit_encoder(self, node: _XdrEnum) -> None:
+        """Emit one encoder function for an XDR enum type"""
+        if node.name in big_endian:
+            template = self.environment.get_template("encoder/enum_be.j2")
+        else:
+            template = self.environment.get_template("encoder/enum.j2")
+        print(template.render(name=node.name))
+
+    def emit_maxsize(self, node: _XdrEnum) -> None:
+        """Emit one maxsize macro for an XDR enum type"""
+        macro_name = get_header_name().upper() + "_" + node.name + "_sz"
+        template = self.environment.get_template("maxsize/enum.j2")
+        print(
+            template.render(
+                macro=macro_name,
+                width=" + ".join(node.symbolic_width()),
+            )
+        )
diff --git a/tools/net/sunrpc/xdrgen/generators/header_bottom.py b/tools/net/sunrpc/xdrgen/generators/header_bottom.py
new file mode 100644
index 000000000000..4b55b282dfc0
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/header_bottom.py
@@ -0,0 +1,33 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate header bottom boilerplate"""
+
+import os.path
+import time
+
+from generators import Boilerplate, header_guard_infix
+from generators import create_jinja2_environment, get_jinja2_template
+from xdr_ast import Specification
+
+
+class XdrHeaderBottomGenerator(Boilerplate):
+    """Generate header boilerplate"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "header_bottom")
+        self.peer = peer
+
+    def emit_declaration(self, filename: str, root: Specification) -> None:
+        """Emit the bottom header guard"""
+        template = get_jinja2_template(self.environment, "declaration", "header")
+        print(template.render(infix=header_guard_infix(filename)))
+
+    def emit_definition(self, filename: str, root: Specification) -> None:
+        """Emit the bottom header guard"""
+        template = get_jinja2_template(self.environment, "definition", "header")
+        print(template.render(infix=header_guard_infix(filename)))
+
+    def emit_source(self, filename: str, root: Specification) -> None:
+        pass
diff --git a/tools/net/sunrpc/xdrgen/generators/header_top.py b/tools/net/sunrpc/xdrgen/generators/header_top.py
new file mode 100644
index 000000000000..c6bc21c71f19
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/header_top.py
@@ -0,0 +1,45 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate header top boilerplate"""
+
+import os.path
+import time
+
+from generators import Boilerplate, header_guard_infix
+from generators import create_jinja2_environment, get_jinja2_template
+from xdr_ast import Specification
+
+
+class XdrHeaderTopGenerator(Boilerplate):
+    """Generate header boilerplate"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "header_top")
+        self.peer = peer
+
+    def emit_declaration(self, filename: str, root: Specification) -> None:
+        """Emit the top header guard"""
+        template = get_jinja2_template(self.environment, "declaration", "header")
+        print(
+            template.render(
+                infix=header_guard_infix(filename),
+                filename=filename,
+                mtime=time.ctime(os.path.getmtime(filename)),
+            )
+        )
+
+    def emit_definition(self, filename: str, root: Specification) -> None:
+        """Emit the top header guard"""
+        template = get_jinja2_template(self.environment, "definition", "header")
+        print(
+            template.render(
+                infix=header_guard_infix(filename),
+                filename=filename,
+                mtime=time.ctime(os.path.getmtime(filename)),
+            )
+        )
+
+    def emit_source(self, filename: str, root: Specification) -> None:
+        pass
diff --git a/tools/net/sunrpc/xdrgen/generators/pointer.py b/tools/net/sunrpc/xdrgen/generators/pointer.py
new file mode 100644
index 000000000000..6dbda60ad2db
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/pointer.py
@@ -0,0 +1,288 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate code to handle XDR pointer types"""
+
+from jinja2 import Environment
+
+from generators import SourceGenerator, kernel_c_type
+from generators import create_jinja2_environment, get_jinja2_template
+
+from xdr_ast import _XdrBasic, _XdrString
+from xdr_ast import _XdrFixedLengthOpaque, _XdrVariableLengthOpaque
+from xdr_ast import _XdrFixedLengthArray, _XdrVariableLengthArray
+from xdr_ast import _XdrOptionalData, _XdrPointer, _XdrDeclaration
+from xdr_ast import public_apis, get_header_name
+
+
+def emit_pointer_declaration(environment: Environment, node: _XdrPointer) -> None:
+    """Emit a declaration pair for an XDR pointer type"""
+    if node.name in public_apis:
+        template = get_jinja2_template(environment, "declaration", "close")
+        print(template.render(name=node.name))
+
+
+def emit_pointer_member_definition(
+    environment: Environment, field: _XdrDeclaration
+) -> None:
+    """Emit a definition for one field in an XDR struct"""
+    if isinstance(field, _XdrBasic):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(template.render(name=field.name))
+    elif isinstance(field, _XdrString):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(template.render(name=field.name))
+    elif isinstance(field, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrOptionalData):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                classifier=field.spec.c_classifier,
+            )
+        )
+
+
+def emit_pointer_definition(environment: Environment, node: _XdrPointer) -> None:
+    """Emit a definition for an XDR pointer type"""
+    template = get_jinja2_template(environment, "definition", "open")
+    print(template.render(name=node.name))
+
+    for field in node.fields[0:-1]:
+        emit_pointer_member_definition(environment, field)
+
+    template = get_jinja2_template(environment, "definition", "close")
+    print(template.render(name=node.name))
+
+
+def emit_pointer_member_decoder(
+    environment: Environment, field: _XdrDeclaration
+) -> None:
+    """Emit a decoder for one field in an XDR pointer"""
+    if isinstance(field, _XdrBasic):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrString):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                size=field.size,
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                maxsize=field.maxsize,
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrOptionalData):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                classifier=field.spec.c_classifier,
+            )
+        )
+
+
+def emit_pointer_decoder(environment: Environment, node: _XdrPointer) -> None:
+    """Emit one decoder function for an XDR pointer type"""
+    template = get_jinja2_template(environment, "decoder", "open")
+    print(template.render(name=node.name))
+
+    for field in node.fields[0:-1]:
+        emit_pointer_member_decoder(environment, field)
+
+    template = get_jinja2_template(environment, "decoder", "close")
+    print(template.render())
+
+
+def emit_pointer_member_encoder(
+    environment: Environment, field: _XdrDeclaration
+) -> None:
+    """Emit an encoder for one field in a XDR pointer"""
+    if isinstance(field, _XdrBasic):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrString):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrOptionalData):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                classifier=field.spec.c_classifier,
+            )
+        )
+
+
+def emit_pointer_encoder(environment: Environment, node: _XdrPointer) -> None:
+    """Emit one encoder function for an XDR pointer type"""
+    template = get_jinja2_template(environment, "encoder", "open")
+    print(template.render(name=node.name))
+
+    for field in node.fields[0:-1]:
+        emit_pointer_member_encoder(environment, field)
+
+    template = get_jinja2_template(environment, "encoder", "close")
+    print(template.render())
+
+
+def emit_pointer_maxsize(environment: Environment, node: _XdrPointer) -> None:
+    """Emit one maxsize macro for an XDR pointer type"""
+    macro_name = get_header_name().upper() + "_" + node.name + "_sz"
+    template = get_jinja2_template(environment, "maxsize", "pointer")
+    print(
+        template.render(
+            macro=macro_name,
+            width=" + ".join(node.symbolic_width()),
+        )
+    )
+
+
+class XdrPointerGenerator(SourceGenerator):
+    """Generate source code for XDR pointer"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "pointer")
+        self.peer = peer
+
+    def emit_declaration(self, node: _XdrPointer) -> None:
+        """Emit one declaration pair for an XDR pointer type"""
+        emit_pointer_declaration(self.environment, node)
+
+    def emit_definition(self, node: _XdrPointer) -> None:
+        """Emit one declaration for an XDR pointer type"""
+        emit_pointer_definition(self.environment, node)
+
+    def emit_decoder(self, node: _XdrPointer) -> None:
+        """Emit one decoder function for an XDR pointer type"""
+        emit_pointer_decoder(self.environment, node)
+
+    def emit_encoder(self, node: _XdrPointer) -> None:
+        """Emit one encoder function for an XDR pointer type"""
+        emit_pointer_encoder(self.environment, node)
+
+    def emit_maxsize(self, node: _XdrPointer) -> None:
+        """Emit one maxsize macro for an XDR pointer type"""
+        emit_pointer_maxsize(self.environment, node)
diff --git a/tools/net/sunrpc/xdrgen/generators/program.py b/tools/net/sunrpc/xdrgen/generators/program.py
new file mode 100644
index 000000000000..ac3cf1694b68
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/program.py
@@ -0,0 +1,168 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate code for an RPC program's procedures"""
+
+from jinja2 import Environment
+
+from generators import SourceGenerator, create_jinja2_environment
+from xdr_ast import _RpcProgram, _RpcVersion, excluded_apis
+
+
+def emit_version_definitions(
+    environment: Environment, program: str, version: _RpcVersion
+) -> None:
+    """Emit procedure numbers for each RPC version's procedures"""
+    template = environment.get_template("definition/open.j2")
+    print(template.render(program=program.upper()))
+
+    template = environment.get_template("definition/procedure.j2")
+    for procedure in version.procedures:
+        if procedure.name not in excluded_apis:
+            print(
+                template.render(
+                    name=procedure.name,
+                    value=procedure.number,
+                )
+            )
+
+    template = environment.get_template("definition/close.j2")
+    print(template.render())
+
+
+def emit_version_declarations(
+    environment: Environment, program: str, version: _RpcVersion
+) -> None:
+    """Emit declarations for each RPC version's procedures"""
+    arguments = dict.fromkeys([])
+    for procedure in version.procedures:
+        if procedure.name not in excluded_apis:
+            arguments[procedure.argument.type_name] = None
+    if len(arguments) > 0:
+        print("")
+        template = environment.get_template("declaration/argument.j2")
+        for argument in arguments:
+            print(template.render(program=program, argument=argument))
+
+    results = dict.fromkeys([])
+    for procedure in version.procedures:
+        if procedure.name not in excluded_apis:
+            results[procedure.result.type_name] = None
+    if len(results) > 0:
+        print("")
+        template = environment.get_template("declaration/result.j2")
+        for result in results:
+            print(template.render(program=program, result=result))
+
+
+def emit_version_argument_decoders(
+    environment: Environment, program: str, version: _RpcVersion
+) -> None:
+    """Emit server argument decoders for each RPC version's procedures"""
+    arguments = dict.fromkeys([])
+    for procedure in version.procedures:
+        if procedure.name not in excluded_apis:
+            arguments[procedure.argument.type_name] = None
+
+    template = environment.get_template("decoder/argument.j2")
+    for argument in arguments:
+        print(template.render(program=program, argument=argument))
+
+
+def emit_version_result_decoders(
+    environment: Environment, program: str, version: _RpcVersion
+) -> None:
+    """Emit client result decoders for each RPC version's procedures"""
+    results = dict.fromkeys([])
+    for procedure in version.procedures:
+        if procedure.name not in excluded_apis:
+            results[procedure.result.type_name] = None
+
+    template = environment.get_template("decoder/result.j2")
+    for result in results:
+        print(template.render(program=program, result=result))
+
+
+def emit_version_argument_encoders(
+    environment: Environment, program: str, version: _RpcVersion
+) -> None:
+    """Emit client argument encoders for each RPC version's procedures"""
+    arguments = dict.fromkeys([])
+    for procedure in version.procedures:
+        if procedure.name not in excluded_apis:
+            arguments[procedure.argument.type_name] = None
+
+    template = environment.get_template("encoder/argument.j2")
+    for argument in arguments:
+        print(template.render(program=program, argument=argument))
+
+
+def emit_version_result_encoders(
+    environment: Environment, program: str, version: _RpcVersion
+) -> None:
+    """Emit server result encoders for each RPC version's procedures"""
+    results = dict.fromkeys([])
+    for procedure in version.procedures:
+        if procedure.name not in excluded_apis:
+            results[procedure.result.type_name] = None
+
+    template = environment.get_template("encoder/result.j2")
+    for result in results:
+        print(template.render(program=program, result=result))
+
+
+class XdrProgramGenerator(SourceGenerator):
+    """Generate source code for an RPC program's procedures"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "program")
+        self.peer = peer
+
+    def emit_definition(self, node: _RpcProgram) -> None:
+        """Emit procedure numbers for each of an RPC programs's procedures"""
+        raw_name = node.name
+        program = raw_name.lower().removesuffix("_program").removesuffix("_prog")
+
+        for version in node.versions:
+            emit_version_definitions(self.environment, program, version)
+
+    def emit_declaration(self, node: _RpcProgram) -> None:
+        """Emit a declaration pair for each of an RPC programs's procedures"""
+        raw_name = node.name
+        program = raw_name.lower().removesuffix("_program").removesuffix("_prog")
+
+        for version in node.versions:
+            emit_version_declarations(self.environment, program, version)
+
+    def emit_decoder(self, node: _RpcProgram) -> None:
+        """Emit all decoder functions for an RPC program's procedures"""
+        raw_name = node.name
+        program = raw_name.lower().removesuffix("_program").removesuffix("_prog")
+        match self.peer:
+            case "server":
+                for version in node.versions:
+                    emit_version_argument_decoders(
+                        self.environment, program, version,
+                    )
+            case "client":
+                for version in node.versions:
+                    emit_version_result_decoders(
+                        self.environment, program, version,
+                    )
+
+    def emit_encoder(self, node: _RpcProgram) -> None:
+        """Emit all encoder functions for an RPC program's procedures"""
+        raw_name = node.name
+        program = raw_name.lower().removesuffix("_program").removesuffix("_prog")
+        match self.peer:
+            case "server":
+                for version in node.versions:
+                    emit_version_result_encoders(
+                        self.environment, program, version,
+                    )
+            case "client":
+                for version in node.versions:
+                    emit_version_argument_encoders(
+                        self.environment, program, version,
+                    )
diff --git a/tools/net/sunrpc/xdrgen/generators/source_top.py b/tools/net/sunrpc/xdrgen/generators/source_top.py
new file mode 100644
index 000000000000..bcf47d93d6f1
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/source_top.py
@@ -0,0 +1,32 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate source code boilerplate"""
+
+import os.path
+import time
+
+from generators import Boilerplate
+from generators import find_xdr_program_name, create_jinja2_environment
+from xdr_ast import _RpcProgram, Specification, get_header_name
+
+
+class XdrSourceTopGenerator(Boilerplate):
+    """Generate source code boilerplate"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "source_top")
+        self.peer = peer
+
+    def emit_source(self, filename: str, root: Specification) -> None:
+        """Emit the top source boilerplate"""
+        name = find_xdr_program_name(root)
+        template = self.environment.get_template(self.peer + ".j2")
+        print(
+            template.render(
+                program=name,
+                filename=filename,
+                mtime=time.ctime(os.path.getmtime(filename)),
+            )
+        )
diff --git a/tools/net/sunrpc/xdrgen/generators/struct.py b/tools/net/sunrpc/xdrgen/generators/struct.py
new file mode 100644
index 000000000000..64911de46f62
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/struct.py
@@ -0,0 +1,288 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate code to handle XDR struct types"""
+
+from jinja2 import Environment
+
+from generators import SourceGenerator, kernel_c_type
+from generators import create_jinja2_environment, get_jinja2_template
+
+from xdr_ast import _XdrBasic, _XdrString
+from xdr_ast import _XdrFixedLengthOpaque, _XdrVariableLengthOpaque
+from xdr_ast import _XdrFixedLengthArray, _XdrVariableLengthArray
+from xdr_ast import _XdrOptionalData, _XdrStruct, _XdrDeclaration
+from xdr_ast import public_apis, get_header_name
+
+
+def emit_struct_declaration(environment: Environment, node: _XdrStruct) -> None:
+    """Emit one declaration pair for an XDR struct type"""
+    if node.name in public_apis:
+        template = get_jinja2_template(environment, "declaration", "close")
+        print(template.render(name=node.name))
+
+
+def emit_struct_member_definition(
+    environment: Environment, field: _XdrDeclaration
+) -> None:
+    """Emit a definition for one field in an XDR struct"""
+    if isinstance(field, _XdrBasic):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(template.render(name=field.name))
+    elif isinstance(field, _XdrString):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(template.render(name=field.name))
+    elif isinstance(field, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrOptionalData):
+        template = get_jinja2_template(environment, "definition", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=kernel_c_type(field.spec),
+                classifier=field.spec.c_classifier,
+            )
+        )
+
+
+def emit_struct_definition(environment: Environment, node: _XdrStruct) -> None:
+    """Emit one definition for an XDR struct type"""
+    template = get_jinja2_template(environment, "definition", "open")
+    print(template.render(name=node.name))
+
+    for field in node.fields:
+        emit_struct_member_definition(environment, field)
+
+    template = get_jinja2_template(environment, "definition", "close")
+    print(template.render(name=node.name))
+
+
+def emit_struct_member_decoder(
+    environment: Environment, field: _XdrDeclaration
+) -> None:
+    """Emit a decoder for one field in an XDR struct"""
+    if isinstance(field, _XdrBasic):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrString):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                size=field.size,
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                maxsize=field.maxsize,
+                classifier=field.spec.c_classifier,
+            )
+        )
+    elif isinstance(field, _XdrOptionalData):
+        template = get_jinja2_template(environment, "decoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                classifier=field.spec.c_classifier,
+            )
+        )
+
+
+def emit_struct_decoder(environment: Environment, node: _XdrStruct) -> None:
+    """Emit one decoder function for an XDR struct type"""
+    template = get_jinja2_template(environment, "decoder", "open")
+    print(template.render(name=node.name))
+
+    for field in node.fields:
+        emit_struct_member_decoder(environment, field)
+
+    template = get_jinja2_template(environment, "decoder", "close")
+    print(template.render())
+
+
+def emit_struct_member_encoder(
+    environment: Environment, field: _XdrDeclaration
+) -> None:
+    """Emit an encoder for one field in an XDR struct"""
+    if isinstance(field, _XdrBasic):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrString):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                size=field.size,
+            )
+        )
+    elif isinstance(field, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                maxsize=field.maxsize,
+            )
+        )
+    elif isinstance(field, _XdrOptionalData):
+        template = get_jinja2_template(environment, "encoder", field.template)
+        print(
+            template.render(
+                name=field.name,
+                type=field.spec.type_name,
+                classifier=field.spec.c_classifier,
+            )
+        )
+
+
+def emit_struct_encoder(environment: Environment, node: _XdrStruct) -> None:
+    """Emit one encoder function for an XDR struct type"""
+    template = get_jinja2_template(environment, "encoder", "open")
+    print(template.render(name=node.name))
+
+    for field in node.fields:
+        emit_struct_member_encoder(environment, field)
+
+    template = get_jinja2_template(environment, "encoder", "close")
+    print(template.render())
+
+
+def emit_struct_maxsize(environment: Environment, node: _XdrStruct) -> None:
+    """Emit one maxsize macro for an XDR struct type"""
+    macro_name = get_header_name().upper() + "_" + node.name + "_sz"
+    template = get_jinja2_template(environment, "maxsize", "struct")
+    print(
+        template.render(
+            macro=macro_name,
+            width=" + ".join(node.symbolic_width()),
+        )
+    )
+
+
+class XdrStructGenerator(SourceGenerator):
+    """Generate source code for XDR structs"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "struct")
+        self.peer = peer
+
+    def emit_declaration(self, node: _XdrStruct) -> None:
+        """Emit one declaration pair for an XDR struct type"""
+        emit_struct_declaration(self.environment, node)
+
+    def emit_definition(self, node: _XdrStruct) -> None:
+        """Emit one definition for an XDR struct type"""
+        emit_struct_definition(self.environment, node)
+
+    def emit_decoder(self, node: _XdrStruct) -> None:
+        """Emit one decoder function for an XDR struct type"""
+        emit_struct_decoder(self.environment, node)
+
+    def emit_encoder(self, node: _XdrStruct) -> None:
+        """Emit one encoder function for an XDR struct type"""
+        emit_struct_encoder(self.environment, node)
+
+    def emit_maxsize(self, node: _XdrStruct) -> None:
+        """Emit one maxsize macro for an XDR struct type"""
+        emit_struct_maxsize(self.environment, node)
diff --git a/tools/net/sunrpc/xdrgen/generators/typedef.py b/tools/net/sunrpc/xdrgen/generators/typedef.py
new file mode 100644
index 000000000000..fab72e9d6915
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/typedef.py
@@ -0,0 +1,271 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate code to handle XDR typedefs"""
+
+from jinja2 import Environment
+
+from generators import SourceGenerator, kernel_c_type
+from generators import create_jinja2_environment, get_jinja2_template
+
+from xdr_ast import _XdrBasic, _XdrTypedef, _XdrString
+from xdr_ast import _XdrFixedLengthOpaque, _XdrVariableLengthOpaque
+from xdr_ast import _XdrFixedLengthArray, _XdrVariableLengthArray
+from xdr_ast import _XdrOptionalData, _XdrVoid, _XdrDeclaration
+from xdr_ast import public_apis, get_header_name
+
+
+def emit_typedef_declaration(environment: Environment, node: _XdrDeclaration) -> None:
+    """Emit a declaration pair for one XDR typedef"""
+    if node.name not in public_apis:
+        return
+    if isinstance(node, _XdrBasic):
+        template = get_jinja2_template(environment, "declaration", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=kernel_c_type(node.spec),
+                classifier=node.spec.c_classifier,
+            )
+        )
+    elif isinstance(node, _XdrString):
+        template = get_jinja2_template(environment, "declaration", node.template)
+        print(template.render(name=node.name))
+    elif isinstance(node, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "declaration", node.template)
+        print(template.render(name=node.name, size=node.size))
+    elif isinstance(node, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "declaration", node.template)
+        print(template.render(name=node.name))
+    elif isinstance(node, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "declaration", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                size=node.size,
+            )
+        )
+    elif isinstance(node, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "declaration", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                classifier=node.spec.c_classifier,
+            )
+        )
+    elif isinstance(node, _XdrOptionalData):
+        raise NotImplementedError("<optional_data> typedef not yet implemented")
+    elif isinstance(node, _XdrVoid):
+        raise NotImplementedError("<void> typedef not yet implemented")
+    else:
+        raise NotImplementedError("typedef: type not recognized")
+
+
+def emit_type_definition(environment: Environment, node: _XdrDeclaration) -> None:
+    """Emit a definition for one XDR typedef"""
+    if isinstance(node, _XdrBasic):
+        template = get_jinja2_template(environment, "definition", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=kernel_c_type(node.spec),
+                classifier=node.spec.c_classifier,
+            )
+        )
+    elif isinstance(node, _XdrString):
+        template = get_jinja2_template(environment, "definition", node.template)
+        print(template.render(name=node.name))
+    elif isinstance(node, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "definition", node.template)
+        print(template.render(name=node.name, size=node.size))
+    elif isinstance(node, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "definition", node.template)
+        print(template.render(name=node.name))
+    elif isinstance(node, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "definition", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                size=node.size,
+            )
+        )
+    elif isinstance(node, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "definition", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                classifier=node.spec.c_classifier,
+            )
+        )
+    elif isinstance(node, _XdrOptionalData):
+        raise NotImplementedError("<optional_data> typedef not yet implemented")
+    elif isinstance(node, _XdrVoid):
+        raise NotImplementedError("<void> typedef not yet implemented")
+    else:
+        raise NotImplementedError("typedef: type not recognized")
+
+
+def emit_typedef_decoder(environment: Environment, node: _XdrDeclaration) -> None:
+    """Emit a decoder function for one XDR typedef"""
+    if isinstance(node, _XdrBasic):
+        template = get_jinja2_template(environment, "decoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+            )
+        )
+    elif isinstance(node, _XdrString):
+        template = get_jinja2_template(environment, "decoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                maxsize=node.maxsize,
+            )
+        )
+    elif isinstance(node, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "decoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                size=node.size,
+            )
+        )
+    elif isinstance(node, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "decoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                maxsize=node.maxsize,
+            )
+        )
+    elif isinstance(node, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "decoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                size=node.size,
+                classifier=node.spec.c_classifier,
+            )
+        )
+    elif isinstance(node, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "decoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                maxsize=node.maxsize,
+            )
+        )
+    elif isinstance(node, _XdrOptionalData):
+        raise NotImplementedError("<optional_data> typedef not yet implemented")
+    elif isinstance(node, _XdrVoid):
+        raise NotImplementedError("<void> typedef not yet implemented")
+    else:
+        raise NotImplementedError("typedef: type not recognized")
+
+
+def emit_typedef_encoder(environment: Environment, node: _XdrDeclaration) -> None:
+    """Emit an encoder function for one XDR typedef"""
+    if isinstance(node, _XdrBasic):
+        template = get_jinja2_template(environment, "encoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+            )
+        )
+    elif isinstance(node, _XdrString):
+        template = get_jinja2_template(environment, "encoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                maxsize=node.maxsize,
+            )
+        )
+    elif isinstance(node, _XdrFixedLengthOpaque):
+        template = get_jinja2_template(environment, "encoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                size=node.size,
+            )
+        )
+    elif isinstance(node, _XdrVariableLengthOpaque):
+        template = get_jinja2_template(environment, "encoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                maxsize=node.maxsize,
+            )
+        )
+    elif isinstance(node, _XdrFixedLengthArray):
+        template = get_jinja2_template(environment, "encoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                size=node.size,
+            )
+        )
+    elif isinstance(node, _XdrVariableLengthArray):
+        template = get_jinja2_template(environment, "encoder", node.template)
+        print(
+            template.render(
+                name=node.name,
+                type=node.spec.type_name,
+                maxsize=node.maxsize,
+            )
+        )
+    elif isinstance(node, _XdrOptionalData):
+        raise NotImplementedError("<optional_data> typedef not yet implemented")
+    elif isinstance(node, _XdrVoid):
+        raise NotImplementedError("<void> typedef not yet implemented")
+    else:
+        raise NotImplementedError("typedef: type not recognized")
+
+
+def emit_typedef_maxsize(environment: Environment, node: _XdrDeclaration) -> None:
+    """Emit a maxsize macro for an XDR typedef"""
+    macro_name = get_header_name().upper() + "_" + node.name + "_sz"
+    template = get_jinja2_template(environment, "maxsize", node.template)
+    print(
+        template.render(
+            macro=macro_name,
+            width=" + ".join(node.symbolic_width()),
+        )
+    )
+
+
+class XdrTypedefGenerator(SourceGenerator):
+    """Generate source code for XDR typedefs"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "typedef")
+        self.peer = peer
+
+    def emit_declaration(self, node: _XdrTypedef) -> None:
+        """Emit one declaration pair for an XDR enum type"""
+        emit_typedef_declaration(self.environment, node.declaration)
+
+    def emit_definition(self, node: _XdrTypedef) -> None:
+        """Emit one definition for an XDR typedef"""
+        emit_type_definition(self.environment, node.declaration)
+
+    def emit_decoder(self, node: _XdrTypedef) -> None:
+        """Emit one decoder function for an XDR typedef"""
+        emit_typedef_decoder(self.environment, node.declaration)
+
+    def emit_encoder(self, node: _XdrTypedef) -> None:
+        """Emit one encoder function for an XDR typedef"""
+        emit_typedef_encoder(self.environment, node.declaration)
+
+    def emit_maxsize(self, node: _XdrTypedef) -> None:
+        """Emit one maxsize macro for an XDR typedef"""
+        emit_typedef_maxsize(self.environment, node.declaration)
diff --git a/tools/net/sunrpc/xdrgen/generators/union.py b/tools/net/sunrpc/xdrgen/generators/union.py
new file mode 100644
index 000000000000..2cca00e279cd
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/generators/union.py
@@ -0,0 +1,275 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Generate code to handle XDR unions"""
+
+from jinja2 import Environment
+
+from generators import SourceGenerator
+from generators import create_jinja2_environment, get_jinja2_template
+
+from xdr_ast import _XdrBasic, _XdrUnion, _XdrVoid, get_header_name
+from xdr_ast import _XdrDeclaration, _XdrCaseSpec, public_apis, big_endian
+
+
+def emit_union_declaration(environment: Environment, node: _XdrUnion) -> None:
+    """Emit one declaration pair for an XDR union type"""
+    if node.name in public_apis:
+        template = get_jinja2_template(environment, "declaration", "close")
+        print(template.render(name=node.name))
+
+
+def emit_union_switch_spec_definition(
+    environment: Environment, node: _XdrDeclaration
+) -> None:
+    """Emit a definition for an XDR union's discriminant"""
+    assert isinstance(node, _XdrBasic)
+    template = get_jinja2_template(environment, "definition", "switch_spec")
+    print(
+        template.render(
+            name=node.name,
+            type=node.spec.type_name,
+            classifier=node.spec.c_classifier,
+        )
+    )
+
+
+def emit_union_case_spec_definition(
+    environment: Environment, node: _XdrDeclaration
+) -> None:
+    """Emit a definition for an XDR union's case arm"""
+    if isinstance(node.arm, _XdrVoid):
+        return
+    assert isinstance(node.arm, _XdrBasic)
+    template = get_jinja2_template(environment, "definition", "case_spec")
+    print(
+        template.render(
+            name=node.arm.name,
+            type=node.arm.spec.type_name,
+            classifier=node.arm.spec.c_classifier,
+        )
+    )
+
+
+def emit_union_definition(environment: Environment, node: _XdrUnion) -> None:
+    """Emit one XDR union definition"""
+    template = get_jinja2_template(environment, "definition", "open")
+    print(template.render(name=node.name))
+
+    emit_union_switch_spec_definition(environment, node.discriminant)
+
+    for case in node.cases:
+        emit_union_case_spec_definition(environment, case)
+
+    if node.default is not None:
+        emit_union_case_spec_definition(environment, node.default)
+
+    template = get_jinja2_template(environment, "definition", "close")
+    print(template.render(name=node.name))
+
+
+def emit_union_switch_spec_decoder(
+    environment: Environment, node: _XdrDeclaration
+) -> None:
+    """Emit a decoder for an XDR union's discriminant"""
+    assert isinstance(node, _XdrBasic)
+    template = get_jinja2_template(environment, "decoder", "switch_spec")
+    print(template.render(name=node.name, type=node.spec.type_name))
+
+
+def emit_union_case_spec_decoder(
+    environment: Environment, node: _XdrCaseSpec, big_endian_discriminant: bool
+) -> None:
+    """Emit decoder functions for an XDR union's case arm"""
+
+    if isinstance(node.arm, _XdrVoid):
+        return
+
+    if big_endian_discriminant:
+        template = get_jinja2_template(environment, "decoder", "case_spec_be")
+    else:
+        template = get_jinja2_template(environment, "decoder", "case_spec")
+    for case in node.values:
+        print(template.render(case=case))
+
+    assert isinstance(node.arm, _XdrBasic)
+    template = get_jinja2_template(environment, "decoder", node.arm.template)
+    print(
+        template.render(
+            name=node.arm.name,
+            type=node.arm.spec.type_name,
+            classifier=node.arm.spec.c_classifier,
+        )
+    )
+
+    template = get_jinja2_template(environment, "decoder", "break")
+    print(template.render())
+
+
+def emit_union_default_spec_decoder(environment: Environment, node: _XdrUnion) -> None:
+    """Emit a decoder function for an XDR union's default arm"""
+    default_case = node.default
+
+    # Avoid a gcc warning about a default case with boolean discriminant
+    if default_case is None and node.discriminant.spec.type_name == "bool":
+        return
+
+    template = get_jinja2_template(environment, "decoder", "default_spec")
+    print(template.render())
+
+    if default_case is None or isinstance(default_case.arm, _XdrVoid):
+        template = get_jinja2_template(environment, "decoder", "break")
+        print(template.render())
+        return
+
+    assert isinstance(default_case.arm, _XdrBasic)
+    template = get_jinja2_template(environment, "decoder", default_case.arm.template)
+    print(
+        template.render(
+            name=default_case.arm.name,
+            type=default_case.arm.spec.type_name,
+            classifier=default_case.arm.spec.c_classifier,
+        )
+    )
+
+
+def emit_union_decoder(environment: Environment, node: _XdrUnion) -> None:
+    """Emit one XDR union decoder"""
+    template = get_jinja2_template(environment, "decoder", "open")
+    print(template.render(name=node.name))
+
+    emit_union_switch_spec_decoder(environment, node.discriminant)
+
+    for case in node.cases:
+        emit_union_case_spec_decoder(
+            environment,
+            case,
+            node.discriminant.spec.type_name in big_endian,
+        )
+
+    emit_union_default_spec_decoder(environment, node)
+
+    template = get_jinja2_template(environment, "decoder", "close")
+    print(template.render())
+
+
+def emit_union_switch_spec_encoder(
+    environment: Environment, node: _XdrDeclaration
+) -> None:
+    """Emit an encoder for an XDR union's discriminant"""
+    assert isinstance(node, _XdrBasic)
+    template = get_jinja2_template(environment, "encoder", "switch_spec")
+    print(template.render(name=node.name, type=node.spec.type_name))
+
+
+def emit_union_case_spec_encoder(
+    environment: Environment, node: _XdrCaseSpec, big_endian_discriminant: bool
+) -> None:
+    """Emit encoder functions for an XDR union's case arm"""
+
+    if isinstance(node.arm, _XdrVoid):
+        return
+
+    if big_endian_discriminant:
+        template = get_jinja2_template(environment, "encoder", "case_spec_be")
+    else:
+        template = get_jinja2_template(environment, "encoder", "case_spec")
+    for case in node.values:
+        print(template.render(case=case))
+
+    template = get_jinja2_template(environment, "encoder", node.arm.template)
+    print(
+        template.render(
+            name=node.arm.name,
+            type=node.arm.spec.type_name,
+        )
+    )
+
+    template = get_jinja2_template(environment, "encoder", "break")
+    print(template.render())
+
+
+def emit_union_default_spec_encoder(environment: Environment, node: _XdrUnion) -> None:
+    """Emit an encoder function for an XDR union's default arm"""
+    default_case = node.default
+
+    # Avoid a gcc warning about a default case with boolean discriminant
+    if default_case is None and node.discriminant.spec.type_name == "bool":
+        return
+
+    template = get_jinja2_template(environment, "encoder", "default_spec")
+    print(template.render())
+
+    if default_case is None or isinstance(default_case.arm, _XdrVoid):
+        template = get_jinja2_template(environment, "encoder", "break")
+        print(template.render())
+        return
+
+    template = get_jinja2_template(environment, "encoder", default_case.arm.template)
+    print(
+        template.render(
+            name=default_case.arm.name,
+            type=default_case.arm.spec.type_name,
+        )
+    )
+
+
+def emit_union_encoder(environment, node: _XdrUnion) -> None:
+    """Emit one XDR union encoder"""
+    template = get_jinja2_template(environment, "encoder", "open")
+    print(template.render(name=node.name))
+
+    emit_union_switch_spec_encoder(environment, node.discriminant)
+
+    for case in node.cases:
+        emit_union_case_spec_encoder(
+            environment,
+            case,
+            node.discriminant.spec.type_name in big_endian,
+        )
+
+    emit_union_default_spec_encoder(environment, node)
+
+    template = get_jinja2_template(environment, "encoder", "close")
+    print(template.render())
+
+
+def emit_union_maxsize(environment: Environment, node: _XdrUnion) -> None:
+    """Emit one maxsize macro for an XDR union type"""
+    macro_name = get_header_name().upper() + "_" + node.name + "_sz"
+    template = get_jinja2_template(environment, "maxsize", "union")
+    print(
+        template.render(
+            macro=macro_name,
+            width=" + ".join(node.symbolic_width()),
+        )
+    )
+
+
+class XdrUnionGenerator(SourceGenerator):
+    """Generate source code for XDR unions"""
+
+    def __init__(self, language: str, peer: str):
+        """Initialize an instance of this class"""
+        self.environment = create_jinja2_environment(language, "union")
+        self.peer = peer
+
+    def emit_declaration(self, node: _XdrUnion) -> None:
+        """Emit one declaration pair for an XDR union"""
+        emit_union_declaration(self.environment, node)
+
+    def emit_definition(self, node: _XdrUnion) -> None:
+        """Emit one definition for an XDR union"""
+        emit_union_definition(self.environment, node)
+
+    def emit_decoder(self, node: _XdrUnion) -> None:
+        """Emit one decoder function for an XDR union"""
+        emit_union_decoder(self.environment, node)
+
+    def emit_encoder(self, node: _XdrUnion) -> None:
+        """Emit one encoder function for an XDR union"""
+        emit_union_encoder(self.environment, node)
+
+    def emit_maxsize(self, node: _XdrUnion) -> None:
+        """Emit one maxsize macro for an XDR union"""
+        emit_union_maxsize(self.environment, node)