def forward_declare(
node: ProtoNode,
root: ProtoNode,
output: OutputFile,
) -> None:
"""Generates code forward-declaring entities in a message's namespace."""
if node.type() != ProtoNode.Type.MESSAGE:
return
namespace = node.cpp_namespace(root)
output.write_line()
output.write_line(f'namespace {namespace} {{')
# Define an enum defining each of the message's fields and their numbers.
output.write_line('enum class Fields {')
with output.indent():
for field in node.fields():
output.write_line(f'{field.enum_name()} = {field.number()},')
output.write_line('};')
# Declare the message's encoder class and all of its enums.
output.write_line()
output.write_line('class Encoder;')
for child in node.children():
if child.type() == ProtoNode.Type.ENUM:
output.write_line()
generate_code_for_enum(child, node, output)
output.write_line(f'}} // namespace {namespace}')
def generate_code_for_package(file_descriptor_proto, package: ProtoNode,
output: OutputFile) -> None:
"""Generates code for a single .pb.h file corresponding to a .proto file."""
assert package.type() == ProtoNode.Type.PACKAGE
output.write_line(f'// {os.path.basename(output.name())} automatically '
f'generated by {PLUGIN_NAME} {PLUGIN_VERSION}')
output.write_line('#pragma once\n')
output.write_line('#include <cstddef>')
output.write_line('#include <cstdint>\n')
output.write_line('#include "pw_protobuf/codegen.h"')
for imported_file in file_descriptor_proto.dependency:
generated_header = _proto_filename_to_generated_header(imported_file)
output.write_line(f'#include "{generated_header}"')
if package.cpp_namespace():
file_namespace = package.cpp_namespace()
if file_namespace.startswith('::'):
file_namespace = file_namespace[2:]
output.write_line(f'\nnamespace {file_namespace} {{')
for node in package:
forward_declare(node, package, output)
# Define all top-level enums.
for node in package.children():
if node.type() == ProtoNode.Type.ENUM:
output.write_line()
generate_code_for_enum(node, package, output)
# Run through all messages in the file, generating a class for each.
for node in package:
if node.type() == ProtoNode.Type.MESSAGE:
output.write_line()
generate_code_for_message(node, package, output)
# Run a second pass through the classes, this time defining all of the
# methods which were previously only declared.
for node in package:
if node.type() == ProtoNode.Type.MESSAGE:
define_not_in_class_methods(node, package, output)
if package.cpp_namespace():
output.write_line(f'\n}} // namespace {package.cpp_namespace()}')