#!/usr/bin/python3 # # Copyright (C) 2023 The Android Open Source Project # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # import os import subprocess from datetime import datetime from utils import CHPP_PARSER_INCLUDE_PATH from utils import CHPP_PARSER_SOURCE_PATH from utils import LICENSE_HEADER from utils import android_build_top_abs_path from utils import system_chre_abs_path class CodeGenerator: """Given an ApiParser object, generates a header file with structure definitions in CHPP format. """ def __init__(self, api, commit_hash): """ :param api: ApiParser object """ self.api = api self.json = api.json # Turn "chre_api/include/chre_api/chre/wwan.h" into "wwan" self.service_name = self.json['filename'].split('/')[-1].split('.')[0] self.capitalized_service_name = self.service_name.capitalize() self.commit_hash = commit_hash # ---------------------------------------------------------------------------------------------- # Header generation methods (plus some methods shared with encoder generation) # ---------------------------------------------------------------------------------------------- def _autogen_notice(self): out = [] out.append('// This file was automatically generated by {}\n'.format( os.path.basename(__file__))) out.append( '// Date: {} UTC\n'.format(datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S'))) out.append( '// Source: {} @ commit {}\n\n'.format(self.json['filename'], self.commit_hash)) out.append( '// DO NOT modify this file directly, as those changes will be lost the next\n') out.append('// time the script is executed\n\n') return out def _dump_to_file(self, output_filename, contents, dry_run, skip_clang_fomat): """Outputs contents to output_filename, or prints contents if dry_run is True""" if dry_run: print('---- {} ----'.format(output_filename)) print(contents) print('---- end of {} ----\n'.format(output_filename)) else: with open(output_filename, 'w') as f: f.write(contents) if not skip_clang_fomat: clang_format_path = (android_build_top_abs_path() + '/prebuilts/clang/host/linux-x86/clang-stable/bin/clang-format') args = [clang_format_path, '-i', output_filename] result = subprocess.run(args) result.check_returncode() def _is_array_type(self, type_info): # If this is an array type, declarators will be a tuple containing a list of # a single int element giving the size of the array return len(type_info.declarators) == 1 and isinstance(type_info.declarators[0], list) def _get_array_len(self, type_info): return type_info.declarators[0][0] def _get_chpp_type_from_chre(self, chre_type): """Returns 'struct ChppWwanCellInfo', etc. given 'chreWwanCellInfo'""" prefix = self._get_struct_or_union_prefix(chre_type) # First see if we have an explicit name override (e.g. for anonymous types) for annotation in self.api.annotations[chre_type]['.']: if annotation['annotation'] == 'rename_type': return prefix + annotation['type_override'] # Otherwise, use the existing type name, just replace the "chre" prefix with "Chpp" if chre_type.startswith('chre'): return prefix + 'Chpp' + chre_type[4:] else: raise RuntimeError( "Couldn't figure out new type name for {}".format(chre_type)) def _get_chre_type_with_prefix(self, chre_type): """Returns 'struct chreWwanCellInfo', etc. given 'chreWwanCellInfo'""" return self._get_struct_or_union_prefix(chre_type) + chre_type def _get_chpp_header_type_from_chre(self, chre_type): """Returns 'struct ChppWwanCellInfoWithHeader', etc. given 'chreWwanCellInfo'""" return self._get_chpp_type_from_chre(chre_type) + 'WithHeader' def _get_member_comment(self, member_info): for annotation in member_info['annotations']: if annotation['annotation'] == 'fixed_value': return ' // Input ignored; always set to {}'.format(annotation['value']) elif annotation['annotation'] == 'var_len_array': return ' // References {} instances of {}'.format( annotation['length_field'], self._get_member_type(member_info)) return '' def _get_member_type(self, member_info, underlying_vla_type=False): """Gets the CHPP type specification prefix for a struct/union member. :param member_info: a dict element from self.api.structs_and_unions[struct]['members'] :param underlying_vla_type: (used only for var-len array types) False to output 'struct ChppOffset', and True to output the type that ChppOffset references :return: type specification string that prefixes the field name, e.g. 'uint8_t' """ # 4 cases to handle: # 1) Annotation gives explicit type that we should use # 2) Annotation says this is a variable length array (so use ChppOffset if # underlying_vla_type is False) # 3) This is a struct/union type, so use the renamed (CHPP) type name # 4) Regular type, e.g. uint32_t, so just use the type spec as-is for annotation in member_info['annotations']: if annotation['annotation'] == 'rewrite_type': return annotation['type_override'] elif not underlying_vla_type and annotation['annotation'] in ['var_len_array', 'string']: return 'struct ChppOffset' if not underlying_vla_type and len(member_info['type'].declarators) > 0 and \ member_info['type'].declarators[0] == '*': # This case should either be handled by rewrite_type (e.g. to uint32_t as # opaque/ignored), or var_len_array raise RuntimeError('Pointer types require annotation\n{}'.format( member_info)) if member_info['is_nested_type']: return self._get_chpp_type_from_chre(member_info['nested_type_name']) return member_info['type'].type_spec def _get_member_type_suffix(self, member_info): if self._is_array_type(member_info['type']): return '[{}]'.format(self._get_array_len(member_info['type'])) return '' def _get_struct_or_union_prefix(self, chre_type): return 'struct ' if not self.api.structs_and_unions[chre_type]['is_union'] else 'union ' def _gen_header_includes(self): """Generates #include directives for use in _types.h""" out = ['#include \n#include \n#include \n\n'] includes = ['chpp/app.h', 'chpp/macros.h', 'chre_api/chre/version.h'] includes.extend(self.json['output_includes']) for incl in sorted(includes): out.append('#include "{}"\n'.format(incl)) out.append('\n') return out def _gen_struct_or_union(self, name): """Generates the definition for a single struct/union type.""" out = [] if not name.startswith('anon'): out.append('//! See {{@link {}}} for details\n'.format(name)) out.append('{} {{\n'.format(self._get_chpp_type_from_chre(name))) for member_info in self.api.structs_and_unions[name]['members']: out.append(' {} {}{};{}\n'.format(self._get_member_type(member_info), member_info['name'], self._get_member_type_suffix( member_info), self._get_member_comment(member_info))) out.append('} CHPP_PACKED_ATTR;\n\n') return out def _gen_header_struct(self, chre_type): """Generates the definition for the type with header (WithHeader).""" out = [] out.append('//! CHPP app header plus {}\n'.format( self._get_chpp_header_type_from_chre(chre_type))) out.append('{} {{\n'.format( self._get_chpp_header_type_from_chre(chre_type))) out.append(' struct ChppAppHeader header;\n') out.append(' {} payload;\n'.format( self._get_chpp_type_from_chre(chre_type))) out.append('} CHPP_PACKED_ATTR;\n\n') return out def _gen_structs_and_unions(self): """Generates definitions for all struct/union types required for the root structs.""" out = [] out.append('CHPP_PACKED_START\n\n') sorted_structs = self._sorted_structs(self.json['root_structs']) for type_name in sorted_structs: out.extend(self._gen_struct_or_union(type_name)) for chre_type in self.json['root_structs']: out.extend(self._gen_header_struct(chre_type)) out.append('CHPP_PACKED_END\n\n') return out def _sorted_structs(self, root_nodes): """Implements a topological sort on self.api.structs_and_unions. Elements are ordered by definition dependency, i.e. if A includes a field of type B, then B will appear before A in the returned list. :return: list of keys in self.api.structs_and_unions, sorted by dependency order """ result = [] visited = set() def sort_helper(collection, key): for dep in sorted(collection[key]['dependencies']): if dep not in visited: visited.add(dep) sort_helper(collection, dep) result.append(key) for node in sorted(root_nodes): sort_helper(self.api.structs_and_unions, node) return result # ---------------------------------------------------------------------------------------------- # Encoder function generation methods (CHRE --> CHPP) # ---------------------------------------------------------------------------------------------- def _get_chpp_member_sizeof_call(self, member_info): """Returns invocation used to determine the size of the provided member when encoded. Will be either sizeof() or a function call if the member contains a VLA :param member_info: a dict element from self.api.structs_and_unions[struct]['members'] :return: string """ type_name = None if member_info['is_nested_type']: chre_type = member_info['nested_type_name'] if self.api.structs_and_unions[chre_type]['has_vla_member']: return '{}(in->{})'.format(self._get_chpp_sizeof_function_name(chre_type), member_info['name']) else: type_name = self._get_chpp_type_from_chre(chre_type) else: type_name = member_info['type'].type_spec return 'sizeof({})'.format(type_name) def _gen_chpp_sizeof_function(self, chre_type): """Generates a function to determine the encoded size of the CHRE struct, if necessary.""" out = [] # Note that this function *should* work with unions as well, but at the time of writing # it'll only be used with structs, so names, etc. are written with that in mind struct_info = self.api.structs_and_unions[chre_type] if not struct_info['has_vla_member']: # No codegen necessary, just sizeof on the CHPP structure name is sufficient return out core_type_name = self._strip_prefix_and_service_from_chre_struct_name( chre_type) parameter_name = core_type_name[0].lower() + core_type_name[1:] chpp_type_name = self._get_chpp_header_type_from_chre(chre_type) out.append('//! @return number of bytes required to represent the given\n' '//! {} along with the CHPP header as\n' '//! {}\n' .format(chre_type, chpp_type_name)) out.append('static size_t {}(\n const {}{} *{}) {{\n' .format(self._get_chpp_sizeof_function_name(chre_type), self._get_struct_or_union_prefix( chre_type), chre_type, parameter_name)) # sizeof(this struct) out.append(' size_t encodedSize = sizeof({});\n'.format(chpp_type_name)) # Plus count * sizeof(type) for each var-len array included in this struct for member_info in self.api.structs_and_unions[chre_type]['members']: for annotation in member_info['annotations']: if annotation['annotation'] == 'var_len_array': # If the VLA field itself contains a VLA, then we'd need to generate a for # loop to calculate the size of each element individually - I don't think we # have any of these in the CHRE API today, so leaving this functionality out. # Also note that to support that case we'd also want to recursively call this # function to generate sizeof functions for nested fields. if member_info['is_nested_type'] and \ self.api.structs_and_unions[member_info['nested_type_name']][ 'has_vla_member']: raise RuntimeError( 'Nested variable-length arrays is not currently supported ({} ' 'in {})'.format(member_info['name'], chre_type)) out.append(' encodedSize += {}->{} * sizeof({});\n'.format( parameter_name, annotation['length_field'], self._get_member_type(member_info, True))) elif annotation['annotation'] == 'string': out.append(' if ({}->{} != NULL) {{'.format( parameter_name, annotation['field'])) out.append(' encodedSize += strlen({}->{}) + 1;\n'.format( parameter_name, annotation['field'])) out.append(' }\n') out.append(' return encodedSize;\n}\n\n') return out def _gen_chpp_sizeof_functions(self): """For each root struct, generate necessary functions to determine their encoded size.""" out = [] for struct in self.json['root_structs']: out.extend(self._gen_chpp_sizeof_function(struct)) return out def _gen_conversion_includes(self): """Generates #include directives for the conversion source file.""" out = ['#include "chpp/macros.h"\n' '#include "chpp/memory.h"\n' '#include "chpp/common/{}_types.h"\n\n'.format(self.service_name)] out.append( '#include \n#include \n#include \n\n') return out def _get_chpp_sizeof_function_name(self, chre_struct): """Returns the function name used to compute the encoded size of the given struct at runtime. """ core_type_name = self._strip_prefix_and_service_from_chre_struct_name( chre_struct) return 'chpp{}SizeOf{}FromChre'.format(self.capitalized_service_name, core_type_name) def _get_encoding_function_name(self, chre_type): core_type_name = self._strip_prefix_and_service_from_chre_struct_name( chre_type) return 'chpp{}Convert{}FromChre'.format(self.capitalized_service_name, core_type_name) def _gen_encoding_function_signature(self, chre_type): out = [] out.append( 'void {}(\n'.format(self._get_encoding_function_name(chre_type))) out.append(' const {}{} *in,\n'.format( self._get_struct_or_union_prefix(chre_type), chre_type)) out.append(' {} *out'.format(self._get_chpp_type_from_chre(chre_type))) if self.api.structs_and_unions[chre_type]['has_vla_member']: out.append(',\n') out.append(' uint8_t *payload,\n') out.append(' size_t payloadSize,\n') out.append(' uint16_t *vlaOffset') out.append(')') return out def _gen_string_encoding(self, member_info, annotation): out = [] # Might want to revisit this if we ever end up supporting NULL strings # in our API. We can assert here since there's currently no API that # does so. member_name = member_info['name'] out.append(' if (in->{} != NULL) {{\n'.format(member_name)) out.append( ' size_t strSize = strlen(in->{}) + 1;\n'.format(member_name)) out.append(' memcpy(&payload[*vlaOffset], in->{}, strSize);\n'.format( member_name)) out.append(' out->{}.length = (uint16_t)(strSize);\n'.format( member_name)) out.append(' out->{}.offset = *vlaOffset;\n'.format(member_name)) out.append(' *vlaOffset += out->{}.length;\n'.format(member_name)) out.append(' } else {\n') out.append(' out->{}.length = 0;\n'.format(member_name)) out.append(' out->{}.offset = 0;\n'.format(member_name)) out.append(' }\n\n') return out def _gen_vla_encoding(self, member_info, annotation): out = [] variable_name = member_info['name'] chpp_type = self._get_member_type(member_info, True) if member_info['is_nested_type']: out.append('\n {} *{} = ({} *) &payload[*vlaOffset];\n'.format( chpp_type, variable_name, chpp_type)) out.append(' out->{}.length = (uint16_t)(in->{} * {});\n'.format( member_info['name'], annotation['length_field'], self._get_chpp_member_sizeof_call(member_info))) out.append(' CHPP_ASSERT((size_t)(*vlaOffset + out->{}.length) <= payloadSize);\n'.format( member_info['name'])) out.append(' if (out->{}.length > 0 &&\n' ' *vlaOffset + out->{}.length <= payloadSize) {{\n'.format( member_info['name'], member_info['name'])) if member_info['is_nested_type']: out.append(' for (size_t i = 0; i < in->{}; i++) {{\n'.format( annotation['length_field'])) out.append(' {}'.format( self._get_assignment_statement_for_field(member_info, in_vla_loop=True))) out.append(' }\n') else: out.append('memcpy(&payload[*vlaOffset], in->{}, in->{} * sizeof({}));\n'.format( member_info['name'], annotation['length_field'], chpp_type)) out.append( ' out->{}.offset = *vlaOffset;\n'.format(member_info['name'])) out.append( ' *vlaOffset += out->{}.length;\n'.format(member_info['name'])) out.append(' } else {\n') out.append(' out->{}.offset = 0;\n'.format(member_info['name'])) out.append(' }\n') return out # ---------------------------------------------------------------------------------------------- # Encoder / decoder function generation methods (CHRE <--> CHPP) # ---------------------------------------------------------------------------------------------- def _get_assignment_statement_for_field(self, member_info, in_vla_loop=False, containing_field_name=None, decode_mode=False): """Returns a statement to assign the provided member :param member_info: :param in_vla_loop: True if we're currently inside a loop and should append [i] :param containing_field_name: Additional member name to use to access the target field, or None; for example the normal case is "out->field = in->field", but if we're generating assignments in the parent conversion function (e.g. as used for union variants), we need to do "out->nested_field.field = in->nested_field.field" :param decode_mode: True converts from CHPP to CHRE. False from CHRE to CHPP :return: assignment statement as a string """ array_index = '[i]' if in_vla_loop else '' output_accessor = '' if in_vla_loop else 'out->' containing_field = containing_field_name + \ '.' if containing_field_name is not None else '' output_variable = '{}{}{}{}'.format(output_accessor, containing_field, member_info['name'], array_index) input_variable = 'in->{}{}{}'.format(containing_field, member_info['name'], array_index) if decode_mode and in_vla_loop: output_variable = '{}Out{}'.format( member_info['name'], array_index) input_variable = '{}In{}'.format(member_info['name'], array_index) if member_info['is_nested_type']: chre_type = member_info['nested_type_name'] has_vla_member = self.api.structs_and_unions[chre_type]['has_vla_member'] if decode_mode: # Use decoding function vla_params = ', inSize' if has_vla_member else '' out = 'if (!{}(&{}, &{}{})) {{\n'.format( self._get_decoding_function_name( chre_type), input_variable, output_variable, vla_params) if has_vla_member: out += ' CHPP_FREE_AND_NULLIFY({}Out);\n'.format( member_info['name']) out += ' return false;\n' out += '}\n' return out else: # Use encoding function vla_params = ', payload, payloadSize, vlaOffset' if has_vla_member else '' return '{}(&{}, &{}{});\n'.format( self._get_encoding_function_name( chre_type), input_variable, output_variable, vla_params) elif self._is_array_type(member_info['type']): # Array of primitive type (e.g. uint32_t[8]) - use memcpy return 'memcpy({}, {}, sizeof({}));\n'.format(output_variable, input_variable, output_variable) else: # Regular assignment return '{} = {};\n'.format(output_variable, input_variable) def _gen_union_variant_conversion_code(self, member_info, annotation, decode_mode): """Generates a switch statement to encode the "active"/"used" field within a union. Handles cases where a union has multiple types, but there's another peer/adjacent field which tells you which field in the union is to be used. Outputs code like this: switch (in->{discriminator field}) { case {first discriminator value associated with a fields}: {conversion code for the field associated with this discriminator value} ... :param chre_type: CHRE type of the union :param annotation: Reference to JSON annotation data with the discriminator mapping data :param decode_mode: False encodes from CHRE to CHPP. True decodes from CHPP to CHRE :return: list of strings """ out = [] chre_type = member_info['nested_type_name'] struct_info = self.api.structs_and_unions[chre_type] # Start off by zeroing out the union field so any padding is set to a consistent value out.append(' memset(&out->{}, 0, sizeof(out->{}));\n'.format(member_info['name'], member_info['name'])) # Next, generate the switch statement that will copy over the proper values out.append( ' switch (in->{}) {{\n'.format(annotation['discriminator'])) for value, field_name in annotation['mapping']: out.append(' case {}:\n'.format(value)) found = False for nested_member_info in struct_info['members']: if nested_member_info['name'] == field_name: out.append(' {}'.format( self._get_assignment_statement_for_field( nested_member_info, containing_field_name=member_info['name'], decode_mode=decode_mode))) found = True break if not found: raise RuntimeError("Invalid mapping - couldn't find target field {} in struct {}" .format(field_name, chre_type)) out.append(' break;\n') out.append(' default:\n' ' CHPP_ASSERT(false);\n' ' }\n') return out def _gen_conversion_function(self, chre_type, already_generated, decode_mode): out = [] struct_info = self.api.structs_and_unions[chre_type] for dependency in sorted(struct_info['dependencies']): if dependency not in already_generated: out.extend( self._gen_conversion_function(dependency, already_generated, decode_mode)) # Skip if we've already generated code for this type, or if it's a union (in which case we # handle the assignment in the parent structure to enable support for discrimination of # which field in the union to use) if chre_type in already_generated or struct_info['is_union']: return out already_generated.add(chre_type) out.append('static ') if decode_mode: out.extend(self._gen_decoding_function_signature(chre_type)) else: out.extend(self._gen_encoding_function_signature(chre_type)) out.append(' {\n') for member_info in self.api.structs_and_unions[chre_type]['members']: generated_by_annotation = False for annotation in member_info['annotations']: if annotation['annotation'] == 'fixed_value': if self._is_array_type(member_info['type']): out.append(' memset(&out->{}, {}, sizeof(out->{}));\n'.format( member_info['name'], annotation['value'], member_info['name'])) else: out.append(' out->{} = {};\n'.format(member_info['name'], annotation['value'])) generated_by_annotation = True break elif annotation['annotation'] == 'enum': # Note: We could generate range verification code here, but it has not # been considered necessary thus far. pass elif annotation['annotation'] == 'var_len_array': if decode_mode: out.extend(self._gen_vla_decoding( member_info, annotation)) else: out.extend(self._gen_vla_encoding( member_info, annotation)) generated_by_annotation = True break elif annotation['annotation'] == 'string': if decode_mode: out.extend(self._gen_string_decoding( member_info, annotation)) else: out.extend(self._gen_string_encoding( member_info, annotation)) generated_by_annotation = True break elif annotation['annotation'] == 'union_variant': out.extend(self._gen_union_variant_conversion_code( member_info, annotation, decode_mode)) generated_by_annotation = True break if not generated_by_annotation: out.append(' {}'.format( self._get_assignment_statement_for_field(member_info, decode_mode=decode_mode))) if decode_mode: out.append('\n return true;\n') out.append('}\n\n') return out def _gen_conversion_functions(self, decode_mode): out = [] already_generated = set() for struct in self.json['root_structs']: out.extend(self._gen_conversion_function( struct, already_generated, decode_mode)) return out def _strip_prefix_and_service_from_chre_struct_name(self, struct): """Strips 'chre' and service prefix, e.g. 'chreWwanCellResultInfo' -> 'CellResultInfo'.""" chre_stripped = struct[4:] upcased_service_name = self.service_name[0].upper( ) + self.service_name[1:] if not struct.startswith('chre') or not chre_stripped.startswith(upcased_service_name): # If this happens, we need to update the script to handle it. Right we assume struct # naming follows the pattern "chre" raise RuntimeError('Unexpected structure name {}'.format(struct)) return chre_stripped[len(self.service_name):] # ---------------------------------------------------------------------------------------------- # Memory allocation generation methods # ---------------------------------------------------------------------------------------------- def _get_chpp_sizeof_call(self, chre_type): """Returns invocation used to determine the size of the provided CHRE struct (with the CHPP app header) after encoding. Like _get_chpp_member_sizeof_call(), except for a top-level type assigned to the variable "in" rather than a member within a structure (e.g. a VLA field) :param chre_type: CHRE type name :return: string """ if self.api.structs_and_unions[chre_type]['has_vla_member']: return '{}(in)'.format(self._get_chpp_sizeof_function_name(chre_type)) else: return 'sizeof({})'.format(self._get_chpp_header_type_from_chre(chre_type)) def _get_encode_allocation_function_name(self, chre_type): core_type_name = self._strip_prefix_and_service_from_chre_struct_name( chre_type) return 'chpp{}{}FromChre'.format(self.capitalized_service_name, core_type_name) def _gen_encode_allocation_function_signature(self, chre_type, gen_docs=False): out = [] if gen_docs: out.append('/**\n' ' * Converts from given CHRE structure to serialized CHPP type.\n' ' *\n' ' * @param in Fully-formed CHRE structure.\n' ' * @param out Upon success, will point to a buffer allocated with ' 'chppMalloc().\n' ' * It is the responsibility of the caller to set the values of the CHPP ' 'app layer header, and to free the buffer when it is no longer needed via ' 'chppFree() or CHPP_FREE_AND_NULLIFY().\n' ' * @param outSize Upon success, will be set to the size of the output ' 'buffer, in bytes.\n' ' *\n' ' * @return true on success, false if memory allocation failed.\n' ' */\n') out.append( 'bool {}(\n'.format(self._get_encode_allocation_function_name(chre_type))) out.append(' const {}{} *in,\n'.format( self._get_struct_or_union_prefix(chre_type), chre_type)) out.append( ' {} **out,\n'.format(self._get_chpp_header_type_from_chre(chre_type))) out.append(' size_t *outSize)') return out def _gen_encode_allocation_function(self, chre_type): out = [] out.extend(self._gen_encode_allocation_function_signature(chre_type)) out.append(' {\n') out.append(' CHPP_NOT_NULL(out);\n') out.append(' CHPP_NOT_NULL(outSize);\n\n') out.append(' size_t payloadSize = {};\n'.format( self._get_chpp_sizeof_call(chre_type))) out.append(' *out = chppMalloc(payloadSize);\n') out.append(' if (*out != NULL) {\n') struct_info = self.api.structs_and_unions[chre_type] if struct_info['has_vla_member']: out.append(' uint8_t *payload = (uint8_t *) &(*out)->payload;\n') out.append(' uint16_t vlaOffset = sizeof({});\n'.format( self._get_chpp_type_from_chre(chre_type))) out.append(' {}(in, &(*out)->payload'.format( self._get_encoding_function_name(chre_type))) if struct_info['has_vla_member']: out.append(', payload, payloadSize, &vlaOffset') out.append(');\n') out.append(' *outSize = payloadSize;\n') out.append(' return true;\n') out.append(' }\n') out.append(' return false;\n}\n\n') return out def _gen_encode_allocation_functions(self): out = [] for chre_type in self.json['root_structs']: out.extend(self._gen_encode_allocation_function(chre_type)) return out def _gen_encode_allocation_function_signatures(self): out = [] for chre_type in self.json['root_structs']: out.extend( self._gen_encode_allocation_function_signature(chre_type, True)) out.append(';\n\n') return out # ---------------------------------------------------------------------------------------------- # Decoder function generation methods (CHPP --> CHRE) # ---------------------------------------------------------------------------------------------- def _get_decoding_function_name(self, chre_type): core_type_name = self._strip_prefix_and_service_from_chre_struct_name( chre_type) return 'chpp{}Convert{}ToChre'.format(self.capitalized_service_name, core_type_name) def _gen_decoding_function_signature(self, chre_type): out = [] out.append( 'bool {}(\n'.format(self._get_decoding_function_name(chre_type))) out.append( ' const {} *in,\n'.format(self._get_chpp_type_from_chre(chre_type))) out.append( ' {} *out'.format(self._get_chre_type_with_prefix(chre_type))) if self.api.structs_and_unions[chre_type]['has_vla_member']: out.append(',\n') out.append(' size_t inSize') out.append(')') return out def _gen_string_decoding(self, member_info, annotation): out = [] variable_name = member_info['name'] out.append('\n') out.append(' if (in->{}.length == 0) {{\n'.format(variable_name)) out.append(' out->{} = NULL;\n'.format(variable_name)) out.append(' } else {\n') out.append(' char *{}Out = chppMalloc(in->{}.length);\n'.format( variable_name, variable_name)) out.append(' if ({}Out == NULL) {{\n'.format(variable_name)) out.append(' return false;\n') out.append(' }\n\n') out.append(' memcpy({}Out, &((const uint8_t *)in)[in->{}.offset],\n'.format( variable_name, variable_name)) out.append(' in->{}.length);\n'.format(variable_name)) out.append(' out->{} = {}Out;\n'.format(variable_name, variable_name)) out.append(' }\n') return out def _gen_vla_decoding(self, member_info, annotation): out = [] variable_name = member_info['name'] chpp_type = self._get_member_type(member_info, True) if member_info['is_nested_type']: chre_type = self._get_chre_type_with_prefix( member_info['nested_type_name']) else: chre_type = chpp_type out.append('\n') out.append(' if (in->{}.length == 0) {{\n'.format(variable_name)) out.append(' out->{} = NULL;\n'.format(variable_name)) out.append(' }\n') out.append(' else {\n') out.append(' if (in->{}.offset + in->{}.length > inSize ||\n'.format( variable_name, variable_name)) out.append(' in->{}.length != in->{} * sizeof({})) {{\n'.format( variable_name, annotation['length_field'], chpp_type)) out.append(' return false;\n') out.append(' }\n\n') if member_info['is_nested_type']: out.append( ' const {} *{}In =\n'.format(chpp_type, variable_name)) out.append(' (const {} *) &((const uint8_t *)in)[in->{}.offset];\n\n'.format( chpp_type, variable_name)) out.append(' {} *{}Out = chppMalloc(in->{} * sizeof({}));\n'.format( chre_type, variable_name, annotation['length_field'], chre_type)) out.append(' if ({}Out == NULL) {{\n'.format(variable_name)) out.append(' return false;\n') out.append(' }\n\n') if member_info['is_nested_type']: out.append(' for (size_t i = 0; i < in->{}; i++) {{\n'.format( annotation['length_field'], variable_name)) out.append(' {}'.format(self._get_assignment_statement_for_field( member_info, in_vla_loop=True, decode_mode=True))) out.append(' }\n') else: out.append(' memcpy({}Out, &((const uint8_t *)in)[in->{}.offset],\n'.format( variable_name, variable_name)) out.append(' in->{} * sizeof({}));\n'.format( annotation['length_field'], chre_type)) out.append(' out->{} = {}Out;\n'.format(variable_name, variable_name)) out.append(' }\n\n') return out def _get_decode_allocation_function_name(self, chre_type): core_type_name = self._strip_prefix_and_service_from_chre_struct_name( chre_type) return 'chpp{}{}ToChre'.format(self.capitalized_service_name, core_type_name) def _gen_decode_allocation_function_signature(self, chre_type, gen_docs=False): out = [] if gen_docs: out.append('/**\n' ' * Converts from serialized CHPP structure to a CHRE type.\n' ' *\n' ' * @param in Fully-formed CHPP structure.\n' ' * @param in Size of the CHPP structure in bytes.\n' ' *\n' ' * @return If successful, a pointer to a CHRE structure allocated with ' 'chppMalloc(). If unsuccessful, null.\n' ' * It is the responsibility of the caller to free the buffer when it is no ' 'longer needed via chppFree() or CHPP_FREE_AND_NULLIFY().\n' ' */\n') out.append('{} *{}(\n'.format( self._get_chre_type_with_prefix(chre_type), self._get_decode_allocation_function_name(chre_type))) out.append( ' const {} *in,\n'.format(self._get_chpp_type_from_chre(chre_type))) out.append(' size_t inSize)') return out def _gen_decode_allocation_function(self, chre_type): out = [] out.extend(self._gen_decode_allocation_function_signature(chre_type)) out.append(' {\n') out.append(' {} *out = NULL;\n\n'.format( self._get_chre_type_with_prefix(chre_type))) out.append(' if (inSize >= sizeof({})) {{\n'.format( self._get_chpp_type_from_chre(chre_type))) out.append(' out = chppMalloc(sizeof({}));\n'.format( self._get_chre_type_with_prefix(chre_type))) out.append(' if (out != NULL) {\n') struct_info = self.api.structs_and_unions[chre_type] out.append(' if (!{}(in, out'.format( self._get_decoding_function_name(chre_type))) if struct_info['has_vla_member']: out.append(', inSize') out.append(')) {') out.append(' CHPP_FREE_AND_NULLIFY(out);\n') out.append(' }\n') out.append(' }\n') out.append(' }\n\n') out.append(' return out;\n') out.append('}\n') return out def _gen_decode_allocation_functions(self): out = [] for chre_type in self.json['root_structs']: out.extend(self._gen_decode_allocation_function(chre_type)) return out def _gen_decode_allocation_function_signatures(self): out = [] for chre_type in self.json['root_structs']: out.extend( self._gen_decode_allocation_function_signature(chre_type, True)) out.append(';\n\n') return out # ---------------------------------------------------------------------------------------------- # Public methods # ---------------------------------------------------------------------------------------------- def generate_header_file(self, dry_run=False, skip_clang_format=False): """Creates a C header file for this API and writes it to the file indicated in the JSON.""" filename = self.service_name + '_types.h' if not dry_run: print('Generating {} ... '.format(filename), end='', flush=True) output_file = os.path.join( system_chre_abs_path(), CHPP_PARSER_INCLUDE_PATH, filename) header = self.generate_header_string() self._dump_to_file(output_file, header, dry_run, skip_clang_format) if not dry_run: print('done') def generate_header_string(self): """Returns a C header with structure definitions for this API.""" # To defer concatenation (speed things up), build the file as a list of strings then only # concatenate once at the end out = [LICENSE_HEADER] header_guard = 'CHPP_{}_TYPES_H_'.format(self.service_name.upper()) out.append('#ifndef {}\n#define {}\n\n'.format( header_guard, header_guard)) out.extend(self._autogen_notice()) out.extend(self._gen_header_includes()) out.append('#ifdef __cplusplus\nextern "C" {\n#endif\n\n') out.extend(self._gen_structs_and_unions()) out.append('\n// Encoding functions (CHRE --> CHPP)\n\n') out.extend(self._gen_encode_allocation_function_signatures()) out.append('\n// Decoding functions (CHPP --> CHRE)\n\n') out.extend(self._gen_decode_allocation_function_signatures()) out.append('#ifdef __cplusplus\n}\n#endif\n\n') out.append('#endif // {}\n'.format(header_guard)) return ''.join(out) def generate_conversion_file(self, dry_run=False, skip_clang_format=False): """Generates a .c file with functions for encoding CHRE structs into CHPP and vice versa.""" filename = self.service_name + '_convert.c' if not dry_run: print('Generating {} ... '.format(filename), end='', flush=True) contents = self.generate_conversion_string() output_file = os.path.join( system_chre_abs_path(), CHPP_PARSER_SOURCE_PATH, filename) self._dump_to_file(output_file, contents, dry_run, skip_clang_format) if not dry_run: print('done') def generate_conversion_string(self): """Returns C code for encoding CHRE structs into CHPP and vice versa.""" out = [LICENSE_HEADER, '\n'] out.extend(self._autogen_notice()) out.extend(self._gen_conversion_includes()) out.append('\n// Encoding (CHRE --> CHPP) size functions\n\n') out.extend(self._gen_chpp_sizeof_functions()) out.append('\n// Encoding (CHRE --> CHPP) conversion functions\n\n') out.extend(self._gen_conversion_functions(False)) out.append('\n// Encoding (CHRE --> CHPP) top-level functions\n\n') out.extend(self._gen_encode_allocation_functions()) out.append('\n// Decoding (CHPP --> CHRE) conversion functions\n\n') out.extend(self._gen_conversion_functions(True)) out.append('\n// Decoding (CHPP --> CHRE) top-level functions\n\n') out.extend(self._gen_decode_allocation_functions()) return ''.join(out)