1 files changed, 510 insertions, 0 deletions
diff --git a/tools/net/sunrpc/xdrgen/xdr_ast.py b/tools/net/sunrpc/xdrgen/xdr_ast.py
new file mode 100644
index 000000000000..dbd3fcf9c957
--- /dev/null
+++ b/tools/net/sunrpc/xdrgen/xdr_ast.py
@@ -0,0 +1,510 @@
+#!/usr/bin/env python3
+# ex: set filetype=python:
+
+"""Define and implement the Abstract Syntax Tree for the XDR language."""
+
+import sys
+from typing import List
+from dataclasses import dataclass
+
+from lark import ast_utils, Transformer
+from lark.tree import Meta
+
+this_module = sys.modules[__name__]
+
+excluded_apis = []
+header_name = "none"
+public_apis = []
+enums = set()
+structs = set()
+pass_by_reference = set()
+
+
+@dataclass
+class _XdrAst(ast_utils.Ast):
+    """Base class for the XDR abstract syntax tree"""
+
+
+@dataclass
+class _XdrIdentifier(_XdrAst):
+    """Corresponds to 'identifier' in the XDR language grammar"""
+
+    symbol: str
+
+
+@dataclass
+class _XdrValue(_XdrAst):
+    """Corresponds to 'value' in the XDR language grammar"""
+
+    value: str
+
+
+@dataclass
+class _XdrConstantValue(_XdrAst):
+    """Corresponds to 'constant' in the XDR language grammar"""
+
+    value: int
+
+
+@dataclass
+class _XdrTypeSpecifier(_XdrAst):
+    """Corresponds to 'type_specifier' in the XDR language grammar"""
+
+    type_name: str
+    c_classifier: str
+
+
+@dataclass
+class _XdrDefinedType(_XdrTypeSpecifier):
+    """Corresponds to a type defined by the input specification"""
+
+
+@dataclass
+class _XdrBuiltInType(_XdrTypeSpecifier):
+    """Corresponds to a built-in XDR type"""
+
+
+@dataclass
+class _XdrDeclaration(_XdrAst):
+    """Base class of XDR type declarations"""
+
+
+@dataclass
+class _XdrFixedLengthOpaque(_XdrDeclaration):
+    """A fixed-length opaque declaration"""
+
+    name: str
+    size: str
+    template: str = "fixed_length_opaque"
+
+
+@dataclass
+class _XdrVariableLengthOpaque(_XdrDeclaration):
+    """A variable-length opaque declaration"""
+
+    name: str
+    maxsize: str
+    template: str = "variable_length_opaque"
+
+
+@dataclass
+class _XdrVariableLengthString(_XdrDeclaration):
+    """A (NUL-terminated) variable-length string declaration"""
+
+    name: str
+    maxsize: str
+    template: str = "variable_length_string"
+
+
+@dataclass
+class _XdrFixedLengthArray(_XdrDeclaration):
+    """A fixed-length array declaration"""
+
+    name: str
+    spec: _XdrTypeSpecifier
+    size: str
+    template: str = "fixed_length_array"
+
+
+@dataclass
+class _XdrVariableLengthArray(_XdrDeclaration):
+    """A variable-length array declaration"""
+
+    name: str
+    spec: _XdrTypeSpecifier
+    maxsize: str
+    template: str = "variable_length_array"
+
+
+@dataclass
+class _XdrOptionalData(_XdrDeclaration):
+    """An 'optional_data' declaration"""
+
+    name: str
+    spec: _XdrTypeSpecifier
+    template: str = "optional_data"
+
+
+@dataclass
+class _XdrBasic(_XdrDeclaration):
+    """A 'basic' declaration"""
+
+    name: str
+    spec: _XdrTypeSpecifier
+    template: str = "basic"
+
+
+@dataclass
+class _XdrVoid(_XdrDeclaration):
+    """A void declaration"""
+
+    template: str = "void"
+
+
+@dataclass
+class _XdrConstant(_XdrAst):
+    """Corresponds to 'constant_def' in the grammar"""
+
+    name: str
+    value: str
+
+
+@dataclass
+class _XdrEnumerator(_XdrAst):
+    """An 'identifier = value' enumerator"""
+
+    name: str
+    value: str
+
+
+@dataclass
+class _XdrEnum(_XdrAst):
+    """An XDR enum definition"""
+
+    name: str
+    minimum: int
+    maximum: int
+    enumerators: List[_XdrEnumerator]
+
+
+@dataclass
+class _XdrStruct(_XdrAst):
+    """An XDR struct definition"""
+
+    name: str
+    fields: List[_XdrDeclaration]
+
+
+@dataclass
+class _XdrPointer(_XdrAst):
+    """An XDR pointer definition"""
+
+    name: str
+    fields: List[_XdrDeclaration]
+
+
+@dataclass
+class _XdrTypedef(_XdrAst):
+    """An XDR typedef"""
+
+    declaration: _XdrDeclaration
+
+
+@dataclass
+class _XdrCaseSpec(_XdrAst):
+    """One case in an XDR union"""
+
+    values: List[str]
+    arm: _XdrDeclaration
+    template: str = "case_spec"
+
+
+@dataclass
+class _XdrDefaultSpec(_XdrAst):
+    """Default case in an XDR union"""
+
+    arm: _XdrDeclaration
+    template: str = "default_spec"
+
+
+@dataclass
+class _XdrUnion(_XdrAst):
+    """An XDR union"""
+
+    name: str
+    discriminant: _XdrDeclaration
+    cases: List[_XdrCaseSpec]
+    default: _XdrDeclaration
+
+
+@dataclass
+class _RpcProcedure(_XdrAst):
+    """RPC procedure definition"""
+
+    name: str
+    number: str
+    argument: _XdrTypeSpecifier
+    result: _XdrTypeSpecifier
+
+
+@dataclass
+class _RpcVersion(_XdrAst):
+    """RPC version definition"""
+
+    name: str
+    number: str
+    procedures: List[_RpcProcedure]
+
+
+@dataclass
+class _RpcProgram(_XdrAst):
+    """RPC program definition"""
+
+    name: str
+    number: str
+    versions: List[_RpcVersion]
+
+
+@dataclass
+class _Pragma(_XdrAst):
+    """Empty class for pragma directives"""
+
+
+@dataclass
+class Definition(_XdrAst, ast_utils.WithMeta):
+    """Corresponds to 'definition' in the grammar"""
+
+    meta: Meta
+    value: _XdrAst
+
+
+@dataclass
+class Specification(_XdrAst, ast_utils.AsList):
+    """Corresponds to 'specification' in the grammar"""
+
+    definitions: List[Definition]
+
+
+class ParseToAst(Transformer):
+    """Functions that transform productions into AST nodes"""
+
+    def identifier(self, children):
+        """Instantiate one _XdrIdentifier object"""
+        return _XdrIdentifier(children[0].value)
+
+    def value(self, children):
+        """Instantiate one _XdrValue object"""
+        if isinstance(children[0], _XdrIdentifier):
+            return _XdrValue(children[0].symbol)
+        return _XdrValue(children[0].children[0].value)
+
+    def constant(self, children):
+        """Instantiate one _XdrConstantValue object"""
+        match children[0].data:
+            case "decimal_constant":
+                value = int(children[0].children[0].value, base=10)
+            case "hexadecimal_constant":
+                value = int(children[0].children[0].value, base=16)
+            case "octal_constant":
+                value = int(children[0].children[0].value, base=8)
+        return _XdrConstantValue(value)
+
+    def type_specifier(self, children):
+        """Instantiate one type_specifier object"""
+        c_classifier = ""
+        if isinstance(children[0], _XdrIdentifier):
+            name = children[0].symbol
+            if name in enums:
+                c_classifier = "enum "
+            if name in structs:
+                c_classifier = "struct "
+            return _XdrDefinedType(
+                type_name=name,
+                c_classifier=c_classifier,
+            )
+
+        token = children[0].data
+        return _XdrBuiltInType(
+            type_name=token.value,
+            c_classifier=c_classifier,
+        )
+
+    def constant_def(self, children):
+        """Instantiate one _XdrConstant object"""
+        name = children[0].symbol
+        value = children[1].value
+        return _XdrConstant(name, value)
+
+    # cel: Python can compute a min() and max() for the enumerator values
+    #      so that the generated code can perform proper range checking.
+    def enum(self, children):
+        """Instantiate one _XdrEnum object"""
+        enum_name = children[0].symbol
+        enums.add(enum_name)
+
+        i = 0
+        enumerators = []
+        body = children[1]
+        while i < len(body.children):
+            name = body.children[i].symbol
+            value = body.children[i + 1].value
+            enumerators.append(_XdrEnumerator(name, value))
+            i = i + 2
+
+        return _XdrEnum(enum_name, 0, 0, enumerators)
+
+    def fixed_length_opaque(self, children):
+        """Instantiate one _XdrFixedLengthOpaque declaration object"""
+        name = children[0].symbol
+        size = children[1].value
+
+        return _XdrFixedLengthOpaque(name, size)
+
+    def variable_length_opaque(self, children):
+        """Instantiate one _XdrVariableLengthOpaque declaration object"""
+        name = children[0].symbol
+        if children[1] is not None:
+            maxsize = children[1].value
+        else:
+            maxsize = "0"
+
+        return _XdrVariableLengthOpaque(name, maxsize)
+
+    def variable_length_string(self, children):
+        """Instantiate one _XdrVariableLengthString declaration object"""
+        name = children[0].symbol
+        if children[1] is not None:
+            maxsize = children[1].value
+        else:
+            maxsize = "0"
+
+        return _XdrVariableLengthString(name, maxsize)
+
+    def fixed_length_array(self, children):
+        """Instantiate one _XdrFixedLengthArray declaration object"""
+        spec = children[0]
+        name = children[1].symbol
+        size = children[2].value
+
+        return _XdrFixedLengthArray(name, spec, size)
+
+    def variable_length_array(self, children):
+        """Instantiate one _XdrVariableLengthArray declaration object"""
+        spec = children[0]
+        name = children[1].symbol
+        if children[2] is not None:
+            maxsize = children[2].value
+        else:
+            maxsize = "0"
+
+        return _XdrVariableLengthArray(name, spec, maxsize)
+
+    def optional_data(self, children):
+        """Instantiate one _XdrOptionalData declaration object"""
+        spec = children[0]
+        name = children[1].symbol
+        structs.add(name)
+        pass_by_reference.add(name)
+
+        return _XdrOptionalData(name, spec)
+
+    def basic(self, children):
+        """Instantiate one _XdrBasic object"""
+        spec = children[0]
+        name = children[1].symbol
+
+        return _XdrBasic(name, spec)
+
+    def void(self, children):
+        """Instantiate one _XdrVoid declaration object"""
+
+        return _XdrVoid()
+
+    def struct(self, children):
+        """Instantiate one _XdrStruct object"""
+        name = children[0].symbol
+        structs.add(name)
+        pass_by_reference.add(name)
+        fields = children[1].children
+
+        last_field = fields[-1]
+        if (
+            isinstance(last_field, _XdrOptionalData)
+            and name == last_field.spec.type_name
+        ):
+            return _XdrPointer(name, fields)
+
+        return _XdrStruct(name, fields)
+
+    def typedef(self, children):
+        """Instantiate one _XdrTypedef object"""
+        new_type = children[0]
+        if isinstance(new_type, _XdrBasic) and isinstance(
+            new_type.spec, _XdrDefinedType
+        ):
+            if new_type.spec.type_name in pass_by_reference:
+                pass_by_reference.add(new_type.name)
+
+        return _XdrTypedef(new_type)
+
+    def case_spec(self, children):
+        """Instantiate one _XdrCaseSpec object"""
+        values = []
+        for item in children[0:-1]:
+            values.append(item.value)
+        arm = children[-1]
+
+        return _XdrCaseSpec(values, arm)
+
+    def default_spec(self, children):
+        """Instantiate one _XdrDefaultSpec object"""
+        arm = children[0]
+
+        return _XdrDefaultSpec(arm)
+
+    def union(self, children):
+        """Instantiate one _XdrUnion object"""
+        name = children[0].symbol
+        structs.add(name)
+        pass_by_reference.add(name)
+
+        body = children[1]
+        discriminant = body.children[0].children[0]
+        cases = body.children[1:-1]
+        default = body.children[-1]
+
+        return _XdrUnion(name, discriminant, cases, default)
+
+    def procedure_def(self, children):
+        """Instantiate one _RpcProcedure object"""
+        result = children[0]
+        name = children[1].symbol
+        argument = children[2]
+        number = children[3].value
+
+        return _RpcProcedure(name, number, argument, result)
+
+    def version_def(self, children):
+        """Instantiate one _RpcVersion object"""
+        name = children[0].symbol
+        number = children[-1].value
+        procedures = children[1:-1]
+
+        return _RpcVersion(name, number, procedures)
+
+    def program_def(self, children):
+        """Instantiate one _RpcProgram object"""
+        name = children[0].symbol
+        number = children[-1].value
+        versions = children[1:-1]
+
+        return _RpcProgram(name, number, versions)
+
+    def pragma_def(self, children):
+        """Instantiate one _Pragma object"""
+        directive = children[0].children[0].data
+        match directive:
+            case "exclude_directive":
+                excluded_apis.append(children[1].symbol)
+            case "header_directive":
+                global header_name
+                header_name = children[1].symbol
+            case "public_directive":
+                public_apis.append(children[1].symbol)
+            case _:
+                raise NotImplementedError("Directive not supported")
+        return _Pragma()
+
+
+transformer = ast_utils.create_transformer(this_module, ParseToAst())
+
+
+def transform_parse_tree(parse_tree):
+    """Transform productions into an abstract syntax tree"""
+
+    return transformer.transform(parse_tree)
+
+
+def get_header_name() -> str:
+    """Return header name set by pragma header directive"""
+    return header_name