[Yunq] First pass at codegen for message headers and parsing.

yunq/codegen_message.py

@@ -0,0 +1,145 @@
+
+from parser import *
+
+HEADER_PRELUDE = """
+// Generated file - DO NOT MODIFY
+#pragma once
+
+#include <glacier/string/string.h>
+
+"""
+
+MESSAGE_CLASS_PREFIX = """
+class {name} {{
+ public:
+  {name}() {{}}
+  // Delete copy and move until implemented.
+  {name}(const {name}&) = delete;
+  {name}({name}&&) = delete;
+
+  void ParseFromBytes(const glcr::ByteBuffer&); 
+  glcr::ByteBuffer SerializeToBytes();
+"""
+
+MESSAGE_CLASS_SET_GET = """
+  {type} {name}() {{ return {name}_; }}
+  void set_{name}({type} value) {{
+    {name}_ = value;
+  }}
+"""
+
+MESSAGE_CLASS_PRIVATE = """
+ private:
+"""
+
+MESSAGE_CLASS_FIELD = """
+  {type} {name}_;
+"""
+
+MESSAGE_CLASS_SUFFIX = """
+}
+"""
+
+type_to_str = {
+        Type.U64: "uint64_t",
+        Type.I64: "int64_t",
+        Type.STRING: "glcr::String",
+        Type.CAPABILITY: "zcap_t",
+        Type.BYTES: "glcr::Vector<uint8_t>"
+        }
+
+def _type_str(field_type: Type) -> str:
+    return type_to_str[field_type]
+
+
+def _generate_message_class(message: Message) -> str:
+    class_decl = MESSAGE_CLASS_PREFIX.format(name = message.name)
+
+    for field in message.fields:
+        class_decl += MESSAGE_CLASS_SET_GET.format(name = field.name, type = _type_str(field.type))
+
+    class_decl += MESSAGE_CLASS_PRIVATE
+
+    for field in message.fields:
+        class_decl += MESSAGE_CLASS_FIELD.format(name = field.name, type = _type_str(field.type))
+    
+    class_decl += MESSAGE_CLASS_SUFFIX
+    return class_decl
+
+
+def generate_message_header(ast: list[Decl]) -> str:
+    header = HEADER_PRELUDE
+
+    for decl in ast:
+        if type(decl) != Message:
+            continue
+        header += _generate_message_class(decl)
+
+    return header
+
+IMPL_PRELUDE = """
+#include "{file}.h"
+
+namespace {{
+
+const uint64_t header_size = 24;  // 4x uint32, 1x uint64
+
+struct ExtPointer {{
+  uint32_t offset;
+  uint32_t length;
+}}
+
+}}  // namespace
+"""
+
+IMPL_PARSE_DEF = """
+void {name}::ParseFromBytes(const glcr::ByteBuffer& bytes) {{
+  CheckHeader();
+"""
+
+IMPL_PARSE_U64 = """
+  set_{name}(bytes.At<uint64_t>(header_size + (8 * {offset})));
+"""
+
+IMPL_PARSE_I64 = """
+  set_{name}(bytes.At<int64_t>(header_size + (8 * {offset})));
+"""
+
+IMPL_PARSE_STRING = """
+  auto {name}_pointer = bytes.At<ExtPointer>(header_size + (8 * {offset}));
+
+  set_{name}(bytes.StringAt({name}_pointer.offset, {name}_pointer.length));
+"""
+
+IMPL_PARSE_DEF_END = """
+}
+"""
+
+def _generate_message_class_impl(message: Message) -> str:
+    impl = IMPL_PARSE_DEF.format(name=message.name) 
+
+    for offset, field in enumerate(message.fields):
+        if field.type == Type.U64:
+            impl += IMPL_PARSE_U64.format(name = field.name, offset = offset)
+        elif field.type == Type.I64:
+            impl += IMPL_PARSE_I64.format(name = field.name, offset = offset)
+        elif field.type == Type.STRING:
+            impl += IMPL_PARSE_STRING.format(name = field.name, offset = offset);
+        else:
+            impl += "\n{} unimplemented\n".format(field.type.name)
+
+    impl += IMPL_PARSE_DEF_END
+
+    return impl
+
+
+def generate_message_impl(file: str, ast: list[Decl]) -> str:
+    impl = IMPL_PRELUDE.format(file=file)
+
+
+    for decl in ast:
+        if type(decl) != Message:
+            continue
+        impl += _generate_message_class_impl(decl)
+
+    return impl