/* * Copyright 2014 Google Inc. All rights reserved. * * 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. */ // independent from idl_parser, since this code is not needed for most clients #include "flatbuffers/flatbuffers.h" #include "flatbuffers/idl.h" #include "flatbuffers/util.h" #include "flatbuffers/code_generators.h" #if defined(FLATBUFFERS_CPP98_STL) #include <cctype> #endif // defined(FLATBUFFERS_CPP98_STL) namespace flatbuffers { // Convert an underscore_based_indentifier in to camelCase. // Also uppercases the first character if first is true. std::string MakeCamel(const std::string &in, bool first) { std::string s; for (size_t i = 0; i < in.length(); i++) { if (!i && first) s += static_cast<char>(toupper(in[0])); else if (in[i] == '_' && i + 1 < in.length()) s += static_cast<char>(toupper(in[++i])); else s += in[i]; } return s; } // These arrays need to correspond to the IDLOptions::k enum. struct LanguageParameters { IDLOptions::Language language; // Whether function names in the language typically start with uppercase. bool first_camel_upper; std::string file_extension; std::string string_type; std::string bool_type; std::string open_curly; std::string accessor_type; std::string const_decl; std::string unsubclassable_decl; std::string enum_decl; std::string enum_separator; std::string getter_prefix; std::string getter_suffix; std::string inheritance_marker; std::string namespace_ident; std::string namespace_begin; std::string namespace_end; std::string set_bb_byteorder; std::string get_bb_position; std::string get_fbb_offset; std::string accessor_prefix; std::string accessor_prefix_static; std::string optional_suffix; std::string includes; std::string class_annotation; CommentConfig comment_config; }; const LanguageParameters& GetLangParams(IDLOptions::Language lang) { static LanguageParameters language_parameters[] = { { IDLOptions::kJava, false, ".java", "String", "boolean ", " {\n", "class ", " final ", "final ", "final class ", ";\n", "()", "", " extends ", "package ", ";", "", "_bb.order(ByteOrder.LITTLE_ENDIAN); ", "position()", "offset()", "", "", "", "import java.nio.*;\nimport java.lang.*;\nimport java.util.*;\nimport com.google.flatbuffers.*;\n", "\n@SuppressWarnings(\"unused\")\n", { "/**", " *", " */", }, }, { IDLOptions::kCSharp, true, ".cs", "string", "bool ", "\n{\n", "struct ", " readonly ", "", "enum ", ",\n", " { get", "} ", " : ", "namespace ", "\n{", "\n}\n", "", "Position", "Offset", "__p.", "Table.", "?", "using global::System;\nusing global::FlatBuffers;\n\n", "", { nullptr, "///", nullptr, }, }, }; if (lang == IDLOptions::kJava) { return language_parameters[0]; } else { assert(lang == IDLOptions::kCSharp); return language_parameters[1]; } } namespace general { class GeneralGenerator : public BaseGenerator { public: GeneralGenerator(const Parser &parser, const std::string &path, const std::string &file_name) : BaseGenerator(parser, path, file_name, "", "."), lang_(GetLangParams(parser_.opts.lang)), cur_name_space_( nullptr ) { } GeneralGenerator &operator=(const GeneralGenerator &); bool generate() { std::string one_file_code; cur_name_space_ = parser_.current_namespace_; for (auto it = parser_.enums_.vec.begin(); it != parser_.enums_.vec.end(); ++it) { std::string enumcode; auto &enum_def = **it; if (!parser_.opts.one_file) cur_name_space_ = enum_def.defined_namespace; GenEnum(enum_def, &enumcode); if (parser_.opts.one_file) { one_file_code += enumcode; } else { if (!SaveType(enum_def.name, *enum_def.defined_namespace, enumcode, false)) return false; } } for (auto it = parser_.structs_.vec.begin(); it != parser_.structs_.vec.end(); ++it) { std::string declcode; auto &struct_def = **it; if (!parser_.opts.one_file) cur_name_space_ = struct_def.defined_namespace; GenStruct(struct_def, &declcode); if (parser_.opts.one_file) { one_file_code += declcode; } else { if (!SaveType(struct_def.name, *struct_def.defined_namespace, declcode, true)) return false; } } if (parser_.opts.one_file) { return SaveType(file_name_, *parser_.current_namespace_, one_file_code, true); } return true; } // Save out the generated code for a single class while adding // declaration boilerplate. bool SaveType(const std::string &defname, const Namespace &ns, const std::string &classcode, bool needs_includes) { if (!classcode.length()) return true; std::string code; if (lang_.language == IDLOptions::kCSharp) { code = "// <auto-generated>\n" "// " + std::string(FlatBuffersGeneratedWarning()) + "\n" "// </auto-generated>\n\n"; } else { code = "// " + std::string(FlatBuffersGeneratedWarning()) + "\n\n"; } std::string namespace_name = FullNamespace(".", ns); if (!namespace_name.empty()) { code += lang_.namespace_ident + namespace_name + lang_.namespace_begin; code += "\n\n"; } if (needs_includes) { code += lang_.includes; if (parser_.opts.gen_nullable) { code += "\nimport javax.annotation.Nullable;\n"; } code += lang_.class_annotation; } code += classcode; if (!namespace_name.empty()) code += lang_.namespace_end; auto filename = NamespaceDir(ns) + defname + lang_.file_extension; return SaveFile(filename.c_str(), code, false); } const Namespace *CurrentNameSpace() const { return cur_name_space_; } std::string FunctionStart(char upper) { return std::string() + (lang_.language == IDLOptions::kJava ? static_cast<char>(tolower(upper)) : upper); } std::string GenNullableAnnotation(const Type& t) { return lang_.language == IDLOptions::kJava && parser_.opts.gen_nullable && !IsScalar(DestinationType(t, true).base_type) ? " @Nullable ": ""; } static bool IsEnum(const Type& type) { return type.enum_def != nullptr && IsInteger(type.base_type); } std::string GenTypeBasic(const Type &type, bool enableLangOverrides) { static const char *java_typename[] = { #define FLATBUFFERS_TD(ENUM, IDLTYPE, \ CTYPE, JTYPE, GTYPE, NTYPE, PTYPE) \ #JTYPE, FLATBUFFERS_GEN_TYPES(FLATBUFFERS_TD) #undef FLATBUFFERS_TD }; static const char *csharp_typename[] = { #define FLATBUFFERS_TD(ENUM, IDLTYPE, \ CTYPE, JTYPE, GTYPE, NTYPE, PTYPE) \ #NTYPE, FLATBUFFERS_GEN_TYPES(FLATBUFFERS_TD) #undef FLATBUFFERS_TD }; if (enableLangOverrides) { if (lang_.language == IDLOptions::kCSharp) { if (IsEnum(type)) return WrapInNameSpace(*type.enum_def); if (type.base_type == BASE_TYPE_STRUCT) { return "Offset<" + WrapInNameSpace(*type.struct_def) + ">"; } } } if (lang_.language == IDLOptions::kJava) { return java_typename[type.base_type]; } else { assert(lang_.language == IDLOptions::kCSharp); return csharp_typename[type.base_type]; } } std::string GenTypeBasic(const Type &type) { return GenTypeBasic(type, true); } std::string GenTypePointer(const Type &type) { switch (type.base_type) { case BASE_TYPE_STRING: return lang_.string_type; case BASE_TYPE_VECTOR: return GenTypeGet(type.VectorType()); case BASE_TYPE_STRUCT: return WrapInNameSpace(*type.struct_def); case BASE_TYPE_UNION: // Unions in C# use a generic Table-derived type for better type safety if (lang_.language == IDLOptions::kCSharp) return "TTable"; // fall through default: return "Table"; } } std::string GenTypeGet(const Type &type) { return IsScalar(type.base_type) ? GenTypeBasic(type) : GenTypePointer(type); } // Find the destination type the user wants to receive the value in (e.g. // one size higher signed types for unsigned serialized values in Java). Type DestinationType(const Type &type, bool vectorelem) { if (lang_.language != IDLOptions::kJava) return type; switch (type.base_type) { // We use int for both uchar/ushort, since that generally means less casting // than using short for uchar. case BASE_TYPE_UCHAR: return Type(BASE_TYPE_INT); case BASE_TYPE_USHORT: return Type(BASE_TYPE_INT); case BASE_TYPE_UINT: return Type(BASE_TYPE_LONG); case BASE_TYPE_VECTOR: if (vectorelem) return DestinationType(type.VectorType(), vectorelem); // else fall thru default: return type; } } std::string GenOffsetType(const StructDef &struct_def) { if(lang_.language == IDLOptions::kCSharp) { return "Offset<" + WrapInNameSpace(struct_def) + ">"; } else { return "int"; } } std::string GenOffsetConstruct(const StructDef &struct_def, const std::string &variable_name) { if(lang_.language == IDLOptions::kCSharp) { return "new Offset<" + WrapInNameSpace(struct_def) + ">(" + variable_name + ")"; } return variable_name; } std::string GenVectorOffsetType() { if(lang_.language == IDLOptions::kCSharp) { return "VectorOffset"; } else { return "int"; } } // Generate destination type name std::string GenTypeNameDest(const Type &type) { return GenTypeGet(DestinationType(type, true)); } // Mask to turn serialized value into destination type value. std::string DestinationMask(const Type &type, bool vectorelem) { if (lang_.language != IDLOptions::kJava) return ""; switch (type.base_type) { case BASE_TYPE_UCHAR: return " & 0xFF"; case BASE_TYPE_USHORT: return " & 0xFFFF"; case BASE_TYPE_UINT: return " & 0xFFFFFFFFL"; case BASE_TYPE_VECTOR: if (vectorelem) return DestinationMask(type.VectorType(), vectorelem); // else fall thru default: return ""; } } // Casts necessary to correctly read serialized data std::string DestinationCast(const Type &type) { if (type.base_type == BASE_TYPE_VECTOR) { return DestinationCast(type.VectorType()); } else { switch (lang_.language) { case IDLOptions::kJava: // Cast necessary to correctly read serialized unsigned values. if (type.base_type == BASE_TYPE_UINT) return "(long)"; break; case IDLOptions::kCSharp: // Cast from raw integral types to enum. if (IsEnum(type)) return "(" + WrapInNameSpace(*type.enum_def) + ")"; break; default: break; } } return ""; } // Cast statements for mutator method parameters. // In Java, parameters representing unsigned numbers need to be cast down to // their respective type. For example, a long holding an unsigned int value // would be cast down to int before being put onto the buffer. In C#, one cast // directly cast an Enum to its underlying type, which is essential before // putting it onto the buffer. std::string SourceCast(const Type &type, bool castFromDest) { if (type.base_type == BASE_TYPE_VECTOR) { return SourceCast(type.VectorType(), castFromDest); } else { switch (lang_.language) { case IDLOptions::kJava: if (castFromDest) { if (type.base_type == BASE_TYPE_UINT) return "(int)"; else if (type.base_type == BASE_TYPE_USHORT) return "(short)"; else if (type.base_type == BASE_TYPE_UCHAR) return "(byte)"; } break; case IDLOptions::kCSharp: if (IsEnum(type)) return "(" + GenTypeBasic(type, false) + ")"; break; default: break; } } return ""; } std::string SourceCast(const Type &type) { return SourceCast(type, true); } std::string SourceCastBasic(const Type &type, bool castFromDest) { return IsScalar(type.base_type) ? SourceCast(type, castFromDest) : ""; } std::string SourceCastBasic(const Type &type) { return SourceCastBasic(type, true); } std::string GenEnumDefaultValue(const Value &value) { auto enum_def = value.type.enum_def; auto vec = enum_def->vals.vec; auto default_value = StringToInt(value.constant.c_str()); auto result = value.constant; for (auto it = vec.begin(); it != vec.end(); ++it) { auto enum_val = **it; if (enum_val.value == default_value) { result = WrapInNameSpace(*enum_def) + "." + enum_val.name; break; } } return result; } std::string GenDefaultValue(const Value &value, bool enableLangOverrides) { if (enableLangOverrides) { // handles both enum case and vector of enum case if (lang_.language == IDLOptions::kCSharp && value.type.enum_def != nullptr && value.type.base_type != BASE_TYPE_UNION) { return GenEnumDefaultValue(value); } } auto longSuffix = lang_.language == IDLOptions::kJava ? "L" : ""; switch (value.type.base_type) { case BASE_TYPE_FLOAT: return value.constant + "f"; case BASE_TYPE_BOOL: return value.constant == "0" ? "false" : "true"; case BASE_TYPE_ULONG: { if (lang_.language != IDLOptions::kJava) return value.constant; // Converts the ulong into its bits signed equivalent uint64_t defaultValue = StringToUInt(value.constant.c_str()); return NumToString(static_cast<int64_t>(defaultValue)) + longSuffix; } case BASE_TYPE_UINT: case BASE_TYPE_LONG: return value.constant + longSuffix; default: return value.constant; } } std::string GenDefaultValue(const Value &value) { return GenDefaultValue(value, true); } std::string GenDefaultValueBasic(const Value &value, bool enableLangOverrides) { if (!IsScalar(value.type.base_type)) { if (enableLangOverrides) { if (lang_.language == IDLOptions::kCSharp) { switch (value.type.base_type) { case BASE_TYPE_STRING: return "default(StringOffset)"; case BASE_TYPE_STRUCT: return "default(Offset<" + WrapInNameSpace(*value.type.struct_def) + ">)"; case BASE_TYPE_VECTOR: return "default(VectorOffset)"; default: break; } } } return "0"; } return GenDefaultValue(value, enableLangOverrides); } std::string GenDefaultValueBasic(const Value &value) { return GenDefaultValueBasic(value, true); } void GenEnum(EnumDef &enum_def, std::string *code_ptr) { std::string &code = *code_ptr; if (enum_def.generated) return; // Generate enum definitions of the form: // public static (final) int name = value; // In Java, we use ints rather than the Enum feature, because we want them // to map directly to how they're used in C/C++ and file formats. // That, and Java Enums are expensive, and not universally liked. GenComment(enum_def.doc_comment, code_ptr, &lang_.comment_config); code += std::string("public ") + lang_.enum_decl + enum_def.name; if (lang_.language == IDLOptions::kCSharp) { code += lang_.inheritance_marker + GenTypeBasic(enum_def.underlying_type, false); } code += lang_.open_curly; if (lang_.language == IDLOptions::kJava) { code += " private " + enum_def.name + "() { }\n"; } for (auto it = enum_def.vals.vec.begin(); it != enum_def.vals.vec.end(); ++it) { auto &ev = **it; GenComment(ev.doc_comment, code_ptr, &lang_.comment_config, " "); if (lang_.language != IDLOptions::kCSharp) { code += " public static"; code += lang_.const_decl; code += GenTypeBasic(enum_def.underlying_type, false); } code += " " + ev.name + " = "; code += NumToString(ev.value); code += lang_.enum_separator; } // Generate a generate string table for enum values. // We do not do that for C# where this functionality is native. if (lang_.language != IDLOptions::kCSharp) { // Problem is, if values are very sparse that could generate really big // tables. Ideally in that case we generate a map lookup instead, but for // the moment we simply don't output a table at all. auto range = enum_def.vals.vec.back()->value - enum_def.vals.vec.front()->value + 1; // Average distance between values above which we consider a table // "too sparse". Change at will. static const int kMaxSparseness = 5; if (range / static_cast<int64_t>(enum_def.vals.vec.size()) < kMaxSparseness) { code += "\n public static"; code += lang_.const_decl; code += lang_.string_type; code += "[] names = { "; auto val = enum_def.vals.vec.front()->value; for (auto it = enum_def.vals.vec.begin(); it != enum_def.vals.vec.end(); ++it) { while (val++ != (*it)->value) code += "\"\", "; code += "\"" + (*it)->name + "\", "; } code += "};\n\n"; code += " public static "; code += lang_.string_type; code += " " + MakeCamel("name", lang_.first_camel_upper); code += "(int e) { return names[e"; if (enum_def.vals.vec.front()->value) code += " - " + enum_def.vals.vec.front()->name; code += "]; }\n"; } } // Close the class code += "}"; // Java does not need the closing semi-colon on class definitions. code += (lang_.language != IDLOptions::kJava) ? ";" : ""; code += "\n\n"; } // Returns the function name that is able to read a value of the given type. std::string GenGetter(const Type &type) { switch (type.base_type) { case BASE_TYPE_STRING: return lang_.accessor_prefix + "__string"; case BASE_TYPE_STRUCT: return lang_.accessor_prefix + "__struct"; case BASE_TYPE_UNION: return lang_.accessor_prefix + "__union"; case BASE_TYPE_VECTOR: return GenGetter(type.VectorType()); default: { std::string getter = lang_.accessor_prefix + "bb." + FunctionStart('G') + "et"; if (type.base_type == BASE_TYPE_BOOL) { getter = "0!=" + getter; } else if (GenTypeBasic(type, false) != "byte") { getter += MakeCamel(GenTypeBasic(type, false)); } return getter; } } } // Returns the function name that is able to read a value of the given type. std::string GenGetterForLookupByKey(flatbuffers::FieldDef *key_field, const std::string &data_buffer, const char *num = nullptr) { auto type = key_field->value.type; auto dest_mask = DestinationMask(type, true); auto dest_cast = DestinationCast(type); auto getter = data_buffer + "." + FunctionStart('G') + "et"; if (GenTypeBasic(type, false) != "byte") { getter += MakeCamel(GenTypeBasic(type, false)); } getter = dest_cast + getter + "(" + GenOffsetGetter(key_field, num) + ")" + dest_mask; return getter; } // Direct mutation is only allowed for scalar fields. // Hence a setter method will only be generated for such fields. std::string GenSetter(const Type &type) { if (IsScalar(type.base_type)) { std::string setter = lang_.accessor_prefix + "bb." + FunctionStart('P') + "ut"; if (GenTypeBasic(type, false) != "byte" && type.base_type != BASE_TYPE_BOOL) { setter += MakeCamel(GenTypeBasic(type, false)); } return setter; } else { return ""; } } // Returns the method name for use with add/put calls. std::string GenMethod(const Type &type) { return IsScalar(type.base_type) ? MakeCamel(GenTypeBasic(type, false)) : (IsStruct(type) ? "Struct" : "Offset"); } // Recursively generate arguments for a constructor, to deal with nested // structs. void GenStructArgs(const StructDef &struct_def, std::string *code_ptr, const char *nameprefix) { std::string &code = *code_ptr; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (IsStruct(field.value.type)) { // Generate arguments for a struct inside a struct. To ensure names // don't clash, and to make it obvious these arguments are constructing // a nested struct, prefix the name with the field name. GenStructArgs(*field.value.type.struct_def, code_ptr, (nameprefix + (field.name + "_")).c_str()); } else { code += ", "; code += GenTypeBasic(DestinationType(field.value.type, false)); code += " "; code += nameprefix; code += MakeCamel(field.name, lang_.first_camel_upper); } } } // Recusively generate struct construction statements of the form: // builder.putType(name); // and insert manual padding. void GenStructBody(const StructDef &struct_def, std::string *code_ptr, const char *nameprefix) { std::string &code = *code_ptr; code += " builder." + FunctionStart('P') + "rep("; code += NumToString(struct_def.minalign) + ", "; code += NumToString(struct_def.bytesize) + ");\n"; for (auto it = struct_def.fields.vec.rbegin(); it != struct_def.fields.vec.rend(); ++it) { auto &field = **it; if (field.padding) { code += " builder." + FunctionStart('P') + "ad("; code += NumToString(field.padding) + ");\n"; } if (IsStruct(field.value.type)) { GenStructBody(*field.value.type.struct_def, code_ptr, (nameprefix + (field.name + "_")).c_str()); } else { code += " builder." + FunctionStart('P') + "ut"; code += GenMethod(field.value.type) + "("; code += SourceCast(field.value.type); auto argname = nameprefix + MakeCamel(field.name, lang_.first_camel_upper); code += argname; code += ");\n"; } } } std::string GenByteBufferLength(const char *bb_name) { std::string bb_len = bb_name; if (lang_.language == IDLOptions::kCSharp) bb_len += ".Length"; else bb_len += ".capacity()"; return bb_len; } std::string GenOffsetGetter(flatbuffers::FieldDef *key_field, const char *num = nullptr) { std::string key_offset = ""; key_offset += lang_.accessor_prefix_static + "__offset(" + NumToString(key_field->value.offset) + ", "; if (num) { key_offset += num; key_offset += (lang_.language == IDLOptions::kCSharp ? ".Value, builder.DataBuffer)" : ", _bb)"); } else { key_offset += GenByteBufferLength("bb"); key_offset += " - tableOffset, bb)"; } return key_offset; } std::string GenLookupKeyGetter(flatbuffers::FieldDef *key_field) { std::string key_getter = " "; key_getter += "int tableOffset = " + lang_.accessor_prefix_static; key_getter += "__indirect(vectorLocation + 4 * (start + middle)"; key_getter += ", bb);\n "; if (key_field->value.type.base_type == BASE_TYPE_STRING) { key_getter += "int comp = " + lang_.accessor_prefix_static; key_getter += FunctionStart('C') + "ompareStrings("; key_getter += GenOffsetGetter(key_field); key_getter += ", byteKey, bb);\n"; } else { auto get_val = GenGetterForLookupByKey(key_field, "bb"); if (lang_.language == IDLOptions::kCSharp) { key_getter += "int comp = " + get_val + ".CompareTo(key);\n"; } else { key_getter += GenTypeNameDest(key_field->value.type) + " val = "; key_getter += get_val + ";\n"; key_getter += " int comp = val > key ? 1 : val < key ? -1 : 0;\n"; } } return key_getter; } std::string GenKeyGetter(flatbuffers::FieldDef *key_field) { std::string key_getter = ""; auto data_buffer = (lang_.language == IDLOptions::kCSharp) ? "builder.DataBuffer" : "_bb"; if (key_field->value.type.base_type == BASE_TYPE_STRING) { if (lang_.language == IDLOptions::kJava) key_getter += " return "; key_getter += lang_.accessor_prefix_static; key_getter += FunctionStart('C') + "ompareStrings("; key_getter += GenOffsetGetter(key_field, "o1") + ", "; key_getter += GenOffsetGetter(key_field, "o2") + ", " + data_buffer + ")"; if (lang_.language == IDLOptions::kJava) key_getter += ";"; } else { auto field_getter = GenGetterForLookupByKey(key_field, data_buffer, "o1"); if (lang_.language == IDLOptions::kCSharp) { key_getter += field_getter; field_getter = GenGetterForLookupByKey(key_field, data_buffer, "o2"); key_getter += ".CompareTo(" + field_getter + ")"; } else { key_getter += "\n " + GenTypeNameDest(key_field->value.type) + " val_1 = "; key_getter += field_getter + ";\n " + GenTypeNameDest(key_field->value.type); key_getter += " val_2 = "; field_getter = GenGetterForLookupByKey(key_field, data_buffer, "o2"); key_getter += field_getter + ";\n"; key_getter += " return val_1 > val_2 ? 1 : val_1 < val_2 ? -1 : 0;\n "; } } return key_getter; } void GenStruct(StructDef &struct_def, std::string *code_ptr) { if (struct_def.generated) return; std::string &code = *code_ptr; // Generate a struct accessor class, with methods of the form: // public type name() { return bb.getType(i + offset); } // or for tables of the form: // public type name() { // int o = __offset(offset); return o != 0 ? bb.getType(o + i) : default; // } GenComment(struct_def.doc_comment, code_ptr, &lang_.comment_config); code += "public "; if (lang_.language == IDLOptions::kCSharp && struct_def.attributes.Lookup("csharp_partial")) { // generate a partial class for this C# struct/table code += "partial "; } else { code += lang_.unsubclassable_decl; } code += lang_.accessor_type + struct_def.name; if (lang_.language == IDLOptions::kCSharp) { code += " : IFlatbufferObject"; code += lang_.open_curly; code += " private "; code += struct_def.fixed ? "Struct" : "Table"; code += " __p;\n"; if (lang_.language == IDLOptions::kCSharp) { code += " public ByteBuffer ByteBuffer { get { return __p.bb; } }\n"; } } else { code += lang_.inheritance_marker; code += struct_def.fixed ? "Struct" : "Table"; code += lang_.open_curly; } if (!struct_def.fixed) { // Generate a special accessor for the table that when used as the root // of a FlatBuffer std::string method_name = FunctionStart('G') + "etRootAs" + struct_def.name; std::string method_signature = " public static " + struct_def.name + " " + method_name; // create convenience method that doesn't require an existing object code += method_signature + "(ByteBuffer _bb) "; code += "{ return " + method_name + "(_bb, new " + struct_def.name+ "()); }\n"; // create method that allows object reuse code += method_signature + "(ByteBuffer _bb, " + struct_def.name + " obj) { "; code += lang_.set_bb_byteorder; code += "return (obj.__assign(_bb." + FunctionStart('G') + "etInt(_bb."; code += lang_.get_bb_position; code += ") + _bb."; code += lang_.get_bb_position; code += ", _bb)); }\n"; if (parser_.root_struct_def_ == &struct_def) { if (parser_.file_identifier_.length()) { // Check if a buffer has the identifier. code += " public static "; code += lang_.bool_type + struct_def.name; code += "BufferHasIdentifier(ByteBuffer _bb) { return "; code += lang_.accessor_prefix_static + "__has_identifier(_bb, \""; code += parser_.file_identifier_; code += "\"); }\n"; } } } // Generate the __init method that sets the field in a pre-existing // accessor object. This is to allow object reuse. code += " public void __init(int _i, ByteBuffer _bb) "; code += "{ " + lang_.accessor_prefix + "bb_pos = _i; "; code += lang_.accessor_prefix + "bb = _bb; }\n"; code += " public " + struct_def.name + " __assign(int _i, ByteBuffer _bb) "; code += "{ __init(_i, _bb); return this; }\n\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; GenComment(field.doc_comment, code_ptr, &lang_.comment_config, " "); std::string type_name = GenTypeGet(field.value.type); std::string type_name_dest = GenTypeNameDest(field.value.type); std::string conditional_cast = ""; std::string optional = ""; if (lang_.language == IDLOptions::kCSharp && !struct_def.fixed && (field.value.type.base_type == BASE_TYPE_STRUCT || field.value.type.base_type == BASE_TYPE_UNION || (field.value.type.base_type == BASE_TYPE_VECTOR && field.value.type.element == BASE_TYPE_STRUCT))) { optional = lang_.optional_suffix; conditional_cast = "(" + type_name_dest + optional + ")"; } std::string dest_mask = DestinationMask(field.value.type, true); std::string dest_cast = DestinationCast(field.value.type); std::string src_cast = SourceCast(field.value.type); std::string method_start = " public " + GenNullableAnnotation(field.value.type) + type_name_dest + optional + " " + MakeCamel(field.name, lang_.first_camel_upper); std::string obj = lang_.language == IDLOptions::kCSharp ? "(new " + type_name + "())" : "obj"; // Most field accessors need to retrieve and test the field offset first, // this is the prefix code for that: auto offset_prefix = " { int o = " + lang_.accessor_prefix + "__offset(" + NumToString(field.value.offset) + "); return o != 0 ? "; // Generate the accessors that don't do object reuse. if (field.value.type.base_type == BASE_TYPE_STRUCT) { // Calls the accessor that takes an accessor object with a new object. if (lang_.language != IDLOptions::kCSharp) { code += method_start + "() { return "; code += MakeCamel(field.name, lang_.first_camel_upper); code += "(new "; code += type_name + "()); }\n"; } } else if (field.value.type.base_type == BASE_TYPE_VECTOR && field.value.type.element == BASE_TYPE_STRUCT) { // Accessors for vectors of structs also take accessor objects, this // generates a variant without that argument. if (lang_.language != IDLOptions::kCSharp) { code += method_start + "(int j) { return "; code += MakeCamel(field.name, lang_.first_camel_upper); code += "(new " + type_name + "(), j); }\n"; } } else if (field.value.type.base_type == BASE_TYPE_UNION) { if (lang_.language == IDLOptions::kCSharp) { // Union types in C# use generic Table-derived type for better type // safety. method_start += "<TTable>"; type_name = type_name_dest; } } std::string getter = dest_cast + GenGetter(field.value.type); code += method_start; std::string default_cast = ""; // only create default casts for c# scalars or vectors of scalars if (lang_.language == IDLOptions::kCSharp && (IsScalar(field.value.type.base_type) || (field.value.type.base_type == BASE_TYPE_VECTOR && IsScalar(field.value.type.element)))) { // For scalars, default value will be returned by GetDefaultValue(). // If the scalar is an enum, GetDefaultValue() returns an actual c# enum // that doesn't need to be casted. However, default values for enum // elements of vectors are integer literals ("0") and are still casted // for clarity. if (field.value.type.enum_def == nullptr || field.value.type.base_type == BASE_TYPE_VECTOR) { default_cast = "(" + type_name_dest + ")"; } } std::string member_suffix = "; "; if (IsScalar(field.value.type.base_type)) { code += lang_.getter_prefix; member_suffix += lang_.getter_suffix; if (struct_def.fixed) { code += " { return " + getter; code += "(" + lang_.accessor_prefix + "bb_pos + "; code += NumToString(field.value.offset) + ")"; code += dest_mask; } else { code += offset_prefix + getter; code += "(o + " + lang_.accessor_prefix + "bb_pos)" + dest_mask; code += " : " + default_cast; code += GenDefaultValue(field.value); } } else { switch (field.value.type.base_type) { case BASE_TYPE_STRUCT: if (lang_.language != IDLOptions::kCSharp) { code += "(" + type_name + " obj" + ")"; } else { code += lang_.getter_prefix; member_suffix += lang_.getter_suffix; } if (struct_def.fixed) { code += " { return " + obj + ".__assign(" + lang_.accessor_prefix; code += "bb_pos + " + NumToString(field.value.offset) + ", "; code += lang_.accessor_prefix + "bb)"; } else { code += offset_prefix + conditional_cast; code += obj + ".__assign("; code += field.value.type.struct_def->fixed ? "o + " + lang_.accessor_prefix + "bb_pos" : lang_.accessor_prefix + "__indirect(o + " + lang_.accessor_prefix + "bb_pos)"; code += ", " + lang_.accessor_prefix + "bb) : null"; } break; case BASE_TYPE_STRING: code += lang_.getter_prefix; member_suffix += lang_.getter_suffix; code += offset_prefix + getter + "(o + " + lang_.accessor_prefix; code += "bb_pos) : null"; break; case BASE_TYPE_VECTOR: { auto vectortype = field.value.type.VectorType(); code += "("; if (vectortype.base_type == BASE_TYPE_STRUCT) { if (lang_.language != IDLOptions::kCSharp) code += type_name + " obj, "; getter = obj + ".__assign"; } code += "int j)" + offset_prefix + conditional_cast + getter +"("; auto index = lang_.accessor_prefix + "__vector(o) + j * " + NumToString(InlineSize(vectortype)); if (vectortype.base_type == BASE_TYPE_STRUCT) { code += vectortype.struct_def->fixed ? index : lang_.accessor_prefix + "__indirect(" + index + ")"; code += ", " + lang_.accessor_prefix + "bb"; } else { code += index; } code += ")" + dest_mask + " : "; code += field.value.type.element == BASE_TYPE_BOOL ? "false" : (IsScalar(field.value.type.element) ? default_cast + "0" : "null"); break; } case BASE_TYPE_UNION: if (lang_.language == IDLOptions::kCSharp) { code += "() where TTable : struct, IFlatbufferObject"; code += offset_prefix + "(TTable?)" + getter; code += "<TTable>(o) : null"; } else { code += "(" + type_name + " obj)" + offset_prefix + getter; code += "(obj, o) : null"; } break; default: assert(0); } } code += member_suffix; code += "}\n"; if (field.value.type.base_type == BASE_TYPE_VECTOR) { code += " public int " + MakeCamel(field.name, lang_.first_camel_upper); code += "Length"; code += lang_.getter_prefix; code += offset_prefix; code += lang_.accessor_prefix + "__vector_len(o) : 0; "; code += lang_.getter_suffix; code += "}\n"; // See if we should generate a by-key accessor. if (field.value.type.element == BASE_TYPE_STRUCT && !field.value.type.struct_def->fixed) { auto &sd = *field.value.type.struct_def; auto &fields = sd.fields.vec; for (auto kit = fields.begin(); kit != fields.end(); ++kit) { auto &key_field = **kit; if (key_field.key) { code += " public " + sd.name + lang_.optional_suffix + " "; code += MakeCamel(field.name, lang_.first_camel_upper) + "ByKey("; code += GenTypeNameDest(key_field.value.type) + " key)"; code += offset_prefix; code += sd.name + ".__lookup_by_key("; code += lang_.accessor_prefix + "__vector(o), key, "; code += lang_.accessor_prefix + "bb) : null; "; code += "}\n"; break; } } } } // Generate a ByteBuffer accessor for strings & vectors of scalars. if ((field.value.type.base_type == BASE_TYPE_VECTOR && IsScalar(field.value.type.VectorType().base_type)) || field.value.type.base_type == BASE_TYPE_STRING) { switch (lang_.language) { case IDLOptions::kJava: code += " public ByteBuffer "; code += MakeCamel(field.name, lang_.first_camel_upper); code += "AsByteBuffer() { return "; code += lang_.accessor_prefix + "__vector_as_bytebuffer("; code += NumToString(field.value.offset) + ", "; code += NumToString(field.value.type.base_type == BASE_TYPE_STRING ? 1 : InlineSize(field.value.type.VectorType())); code += "); }\n"; break; case IDLOptions::kCSharp: code += " public ArraySegment<byte>? Get"; code += MakeCamel(field.name, lang_.first_camel_upper); code += "Bytes() { return "; code += lang_.accessor_prefix + "__vector_as_arraysegment("; code += NumToString(field.value.offset); code += "); }\n"; break; default: break; } } // generate object accessors if is nested_flatbuffer if (field.nested_flatbuffer) { auto nested_type_name = WrapInNameSpace(*field.nested_flatbuffer); auto nested_method_name = MakeCamel(field.name, lang_.first_camel_upper) + "As" + nested_type_name; auto get_nested_method_name = nested_method_name; if (lang_.language == IDLOptions::kCSharp) { get_nested_method_name = "Get" + nested_method_name; conditional_cast = "(" + nested_type_name + lang_.optional_suffix + ")"; } if (lang_.language != IDLOptions::kCSharp) { code += " public " + nested_type_name + lang_.optional_suffix + " "; code += nested_method_name + "() { return "; code += get_nested_method_name + "(new " + nested_type_name + "()); }\n"; } else { obj = "(new " + nested_type_name + "())"; } code += " public " + nested_type_name + lang_.optional_suffix + " "; code += get_nested_method_name + "("; if (lang_.language != IDLOptions::kCSharp) code += nested_type_name + " obj"; code += ") { int o = " + lang_.accessor_prefix + "__offset("; code += NumToString(field.value.offset) +"); "; code += "return o != 0 ? " + conditional_cast + obj + ".__assign("; code += lang_.accessor_prefix; code += "__indirect(" + lang_.accessor_prefix + "__vector(o)), "; code += lang_.accessor_prefix + "bb) : null; }\n"; } // Generate mutators for scalar fields or vectors of scalars. if (parser_.opts.mutable_buffer) { auto underlying_type = field.value.type.base_type == BASE_TYPE_VECTOR ? field.value.type.VectorType() : field.value.type; // Boolean parameters have to be explicitly converted to byte // representation. auto setter_parameter = underlying_type.base_type == BASE_TYPE_BOOL ? "(byte)(" + field.name + " ? 1 : 0)" : field.name; auto mutator_prefix = MakeCamel("mutate", lang_.first_camel_upper); // A vector mutator also needs the index of the vector element it should // mutate. auto mutator_params = (field.value.type.base_type == BASE_TYPE_VECTOR ? "(int j, " : "(") + GenTypeNameDest(underlying_type) + " " + field.name + ") { "; auto setter_index = field.value.type.base_type == BASE_TYPE_VECTOR ? lang_.accessor_prefix + "__vector(o) + j * " + NumToString(InlineSize(underlying_type)) : (struct_def.fixed ? lang_.accessor_prefix + "bb_pos + " + NumToString(field.value.offset) : "o + " + lang_.accessor_prefix + "bb_pos"); if (IsScalar(field.value.type.base_type) || (field.value.type.base_type == BASE_TYPE_VECTOR && IsScalar(field.value.type.VectorType().base_type))) { code += " public "; code += struct_def.fixed ? "void " : lang_.bool_type; code += mutator_prefix + MakeCamel(field.name, true); code += mutator_params; if (struct_def.fixed) { code += GenSetter(underlying_type) + "(" + setter_index + ", "; code += src_cast + setter_parameter + "); }\n"; } else { code += "int o = " + lang_.accessor_prefix + "__offset("; code += NumToString(field.value.offset) + ");"; code += " if (o != 0) { " + GenSetter(underlying_type); code += "(" + setter_index + ", " + src_cast + setter_parameter + "); return true; } else { return false; } }\n"; } } } } code += "\n"; flatbuffers::FieldDef *key_field = nullptr; if (struct_def.fixed) { // create a struct constructor function code += " public static " + GenOffsetType(struct_def) + " "; code += FunctionStart('C') + "reate"; code += struct_def.name + "(FlatBufferBuilder builder"; GenStructArgs(struct_def, code_ptr, ""); code += ") {\n"; GenStructBody(struct_def, code_ptr, ""); code += " return "; code += GenOffsetConstruct(struct_def, "builder." + std::string(lang_.get_fbb_offset)); code += ";\n }\n"; } else { // Generate a method that creates a table in one go. This is only possible // when the table has no struct fields, since those have to be created // inline, and there's no way to do so in Java. bool has_no_struct_fields = true; int num_fields = 0; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; if (IsStruct(field.value.type)) { has_no_struct_fields = false; } else { num_fields++; } } // JVM specifications restrict default constructor params to be < 255. // Longs and doubles take up 2 units, so we set the limit to be < 127. if (has_no_struct_fields && num_fields && num_fields < 127) { // Generate a table constructor of the form: // public static int createName(FlatBufferBuilder builder, args...) code += " public static " + GenOffsetType(struct_def) + " "; code += FunctionStart('C') + "reate" + struct_def.name; code += "(FlatBufferBuilder builder"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; code += ",\n "; code += GenTypeBasic(DestinationType(field.value.type, false)); code += " "; code += field.name; if (!IsScalar(field.value.type.base_type)) code += "Offset"; // Java doesn't have defaults, which means this method must always // supply all arguments, and thus won't compile when fields are added. if (lang_.language != IDLOptions::kJava) { code += " = "; code += GenDefaultValueBasic(field.value); } } code += ") {\n builder."; code += FunctionStart('S') + "tartObject("; code += NumToString(struct_def.fields.vec.size()) + ");\n"; for (size_t size = struct_def.sortbysize ? sizeof(largest_scalar_t) : 1; size; size /= 2) { for (auto it = struct_def.fields.vec.rbegin(); it != struct_def.fields.vec.rend(); ++it) { auto &field = **it; if (!field.deprecated && (!struct_def.sortbysize || size == SizeOf(field.value.type.base_type))) { code += " " + struct_def.name + "."; code += FunctionStart('A') + "dd"; code += MakeCamel(field.name) + "(builder, " + field.name; if (!IsScalar(field.value.type.base_type)) code += "Offset"; code += ");\n"; } } } code += " return " + struct_def.name + "."; code += FunctionStart('E') + "nd" + struct_def.name; code += "(builder);\n }\n\n"; } // Generate a set of static methods that allow table construction, // of the form: // public static void addName(FlatBufferBuilder builder, short name) // { builder.addShort(id, name, default); } // Unlike the Create function, these always work. code += " public static void " + FunctionStart('S') + "tart"; code += struct_def.name; code += "(FlatBufferBuilder builder) { builder."; code += FunctionStart('S') + "tartObject("; code += NumToString(struct_def.fields.vec.size()) + "); }\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; if (field.key) key_field = &field; code += " public static void " + FunctionStart('A') + "dd"; code += MakeCamel(field.name); code += "(FlatBufferBuilder builder, "; code += GenTypeBasic(DestinationType(field.value.type, false)); auto argname = MakeCamel(field.name, false); if (!IsScalar(field.value.type.base_type)) argname += "Offset"; code += " " + argname + ") { builder." + FunctionStart('A') + "dd"; code += GenMethod(field.value.type) + "("; code += NumToString(it - struct_def.fields.vec.begin()) + ", "; code += SourceCastBasic(field.value.type); code += argname; if (!IsScalar(field.value.type.base_type) && field.value.type.base_type != BASE_TYPE_UNION && lang_.language == IDLOptions::kCSharp) { code += ".Value"; } code += ", "; if (lang_.language == IDLOptions::kJava) code += SourceCastBasic( field.value.type ); code += GenDefaultValue(field.value, false); code += "); }\n"; if (field.value.type.base_type == BASE_TYPE_VECTOR) { auto vector_type = field.value.type.VectorType(); auto alignment = InlineAlignment(vector_type); auto elem_size = InlineSize(vector_type); if (!IsStruct(vector_type)) { // Generate a method to create a vector from a Java array. code += " public static " + GenVectorOffsetType() + " "; code += FunctionStart('C') + "reate"; code += MakeCamel(field.name); code += "Vector(FlatBufferBuilder builder, "; code += GenTypeBasic(vector_type) + "[] data) "; code += "{ builder." + FunctionStart('S') + "tartVector("; code += NumToString(elem_size); code += ", data." + FunctionStart('L') + "ength, "; code += NumToString(alignment); code += "); for (int i = data."; code += FunctionStart('L') + "ength - 1; i >= 0; i--) builder."; code += FunctionStart('A') + "dd"; code += GenMethod(vector_type); code += "("; code += SourceCastBasic(vector_type, false); code += "data[i]"; if (lang_.language == IDLOptions::kCSharp && (vector_type.base_type == BASE_TYPE_STRUCT || vector_type.base_type == BASE_TYPE_STRING)) code += ".Value"; code += "); return "; code += "builder." + FunctionStart('E') + "ndVector(); }\n"; } // Generate a method to start a vector, data to be added manually after. code += " public static void " + FunctionStart('S') + "tart"; code += MakeCamel(field.name); code += "Vector(FlatBufferBuilder builder, int numElems) "; code += "{ builder." + FunctionStart('S') + "tartVector("; code += NumToString(elem_size); code += ", numElems, " + NumToString(alignment); code += "); }\n"; } } code += " public static " + GenOffsetType(struct_def) + " "; code += FunctionStart('E') + "nd" + struct_def.name; code += "(FlatBufferBuilder builder) {\n int o = builder."; code += FunctionStart('E') + "ndObject();\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (!field.deprecated && field.required) { code += " builder." + FunctionStart('R') + "equired(o, "; code += NumToString(field.value.offset); code += "); // " + field.name + "\n"; } } code += " return " + GenOffsetConstruct(struct_def, "o") + ";\n }\n"; if (parser_.root_struct_def_ == &struct_def) { code += " public static void "; code += FunctionStart('F') + "inish" + struct_def.name; code += "Buffer(FlatBufferBuilder builder, " + GenOffsetType(struct_def); code += " offset) {"; code += " builder." + FunctionStart('F') + "inish(offset"; if (lang_.language == IDLOptions::kCSharp) { code += ".Value"; } if (parser_.file_identifier_.length()) code += ", \"" + parser_.file_identifier_ + "\""; code += "); }\n"; } } // Only generate key compare function for table, // because `key_field` is not set for struct if (struct_def.has_key && !struct_def.fixed) { if (lang_.language == IDLOptions::kJava) { code += "\n @Override\n protected int keysCompare("; code += "Integer o1, Integer o2, ByteBuffer _bb) {"; code += GenKeyGetter(key_field); code += " }\n"; } else { code += "\n public static VectorOffset "; code += "CreateSortedVectorOf" + struct_def.name; code += "(FlatBufferBuilder builder, "; code += "Offset<" + struct_def.name + ">"; code += "[] offsets) {\n"; code += " Array.Sort(offsets, (Offset<" + struct_def.name + "> o1, Offset<" + struct_def.name + "> o2) => " + GenKeyGetter(key_field); code += ");\n"; code += " return builder.CreateVectorOfTables(offsets);\n }\n"; } code += "\n public static " + struct_def.name + lang_.optional_suffix; code += " __lookup_by_key(int vectorLocation, "; code += GenTypeNameDest(key_field->value.type); code += " key, ByteBuffer bb) {\n"; if (key_field->value.type.base_type == BASE_TYPE_STRING) { code += " byte[] byteKey = "; if (lang_.language == IDLOptions::kJava) code += "key.getBytes(Table.UTF8_CHARSET.get());\n"; else code += "System.Text.Encoding.UTF8.GetBytes(key);\n"; } code += " int span = "; code += "bb." + FunctionStart('G') + "etInt(vectorLocation - 4);\n"; code += " int start = 0;\n"; code += " while (span != 0) {\n"; code += " int middle = span / 2;\n"; code += GenLookupKeyGetter(key_field); code += " if (comp > 0) {\n"; code += " span = middle;\n"; code += " } else if (comp < 0) {\n"; code += " middle++;\n"; code += " start += middle;\n"; code += " span -= middle;\n"; code += " } else {\n"; code += " return new " + struct_def.name; code += "().__assign(tableOffset, bb);\n"; code += " }\n }\n"; code += " return null;\n"; code += " }\n"; } code += "}"; // Java does not need the closing semi-colon on class definitions. code += (lang_.language != IDLOptions::kJava) ? ";" : ""; code += "\n\n"; } const LanguageParameters& lang_; // This tracks the current namespace used to determine if a type need to be prefixed by its namespace const Namespace *cur_name_space_; }; } // namespace general bool GenerateGeneral(const Parser &parser, const std::string &path, const std::string &file_name) { general::GeneralGenerator generator(parser, path, file_name); return generator.generate(); } std::string GeneralMakeRule(const Parser &parser, const std::string &path, const std::string &file_name) { assert(parser.opts.lang <= IDLOptions::kMAX); const auto &lang = GetLangParams(parser.opts.lang); std::string make_rule; for (auto it = parser.enums_.vec.begin(); it != parser.enums_.vec.end(); ++it) { auto &enum_def = **it; if (make_rule != "") make_rule += " "; std::string directory = BaseGenerator::NamespaceDir(parser, path, *enum_def.defined_namespace); make_rule += directory + enum_def.name + lang.file_extension; } for (auto it = parser.structs_.vec.begin(); it != parser.structs_.vec.end(); ++it) { auto &struct_def = **it; if (make_rule != "") make_rule += " "; std::string directory = BaseGenerator::NamespaceDir(parser, path, *struct_def.defined_namespace); make_rule += directory + struct_def.name + lang.file_extension; } make_rule += ": "; auto included_files = parser.GetIncludedFilesRecursive(file_name); for (auto it = included_files.begin(); it != included_files.end(); ++it) { make_rule += " " + *it; } return make_rule; } std::string BinaryFileName(const Parser &parser, const std::string &path, const std::string &file_name) { auto ext = parser.file_extension_.length() ? parser.file_extension_ : "bin"; return path + file_name + "." + ext; } bool GenerateBinary(const Parser &parser, const std::string &path, const std::string &file_name) { return !parser.builder_.GetSize() || flatbuffers::SaveFile( BinaryFileName(parser, path, file_name).c_str(), reinterpret_cast<char *>(parser.builder_.GetBufferPointer()), parser.builder_.GetSize(), true); } std::string BinaryMakeRule(const Parser &parser, const std::string &path, const std::string &file_name) { if (!parser.builder_.GetSize()) return ""; std::string filebase = flatbuffers::StripPath( flatbuffers::StripExtension(file_name)); std::string make_rule = BinaryFileName(parser, path, filebase) + ": " + file_name; auto included_files = parser.GetIncludedFilesRecursive( parser.root_struct_def_->file); for (auto it = included_files.begin(); it != included_files.end(); ++it) { make_rule += " " + *it; } return make_rule; } } // namespace flatbuffers