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Helps simplify code generation code. Instead of this:
code += "inline const " + cpp_qualified_name + " *Get";
code += name;
code += "(const void *buf) {\n return flatbuffers::GetRoot<";
code += cpp_qualified_name + ">(buf);\n}\n\n";
You do this:
code.SetValue("NAME", struct_def.name);
code.SetValue("CPP_NAME", cpp_qualified_name);
code += "inline const {{CPP_NAME}} *Get{{NAME}}(const void *buf) {";
code += " return flatbuffers::GetRoot<{{CPP_NAME}}>(buf);";
code += "}";
code += "";
Updated the CPP code generator to use the CodeWriter class. Most of the
changes in the generated code are white-space changes, esp. around new
lines (since the code generator class automatically appends new lines
when appending a string). Actual code changes include:
* Renamed "rehasher" to "_rehasher" for consistency with other args in
Pack function.
* Renamed "union_obj" to "obj: in UnPack function.
* Always do "(void)_o;" to prevent unused variable warning in Create
function (instead of only doing it if there are no fields) in order
to avoid two-passes.
* Renamed padding variables from __paddingX to paddingX__.
"Each name that contains a double underscore (_ _) [...] is reserved
to the implementation for any use." C++ standards 17.4.3.1.2.
* Add braces around switch cases.
* Calculate index as a separate statement in EnumName function, eg.
const size_t index = ...;
return EnumNamesX()[index];
vs.
return EnumNamesX()[...];
* Stored end table offset in variable in Finish() functions, eg.
const auto end = fbb_.EndTable(start_, ...);
auto o = flatbuffers::Offset<T>(end);
vs.
auto o = flatbuffers::Offset<T>(fbb_.EndTable(start, ...));
* Separate reinterpret_cast calls from function calls in Union
functions, eg.
auto ptr = reinterpret_cast<const T *>(obj);
return ptr->UnPack(resolver);
vs.
return reinterpret_cast<const T *>(obj)->UnPack(resolver);
* Removed unecessary (void)(padding__X) no-ops from constructors, eg.
Test(int16_t a, int8_t b) : ... {
(void)__padding0; // <-- Removed this line.
}
In the idl_gen_cpp.cpp file itself, I refactored some code generation into
new functions: GenParam, GenNativeTable, GenVerifyCall, GenBuilders,
GenUnpackFieldStatement, and GenCreateParam.
Change-Id: I727b1bd8719d05b7ce33cbce00eb58fda817b25d
159 lines
5.0 KiB
C++
159 lines
5.0 KiB
C++
/*
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* Copyright 2016 Google Inc. All rights reserved.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include "flatbuffers/code_generators.h"
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#include <assert.h>
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#include "flatbuffers/util.h"
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namespace flatbuffers {
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void CodeWriter::operator+=(std::string text) {
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while (true) {
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auto begin = text.find("{{");
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if (begin == std::string::npos) {
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break;
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}
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auto end = text.find("}}");
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if (end == std::string::npos || end < begin) {
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break;
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}
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// Write all the text before the first {{ into the stream.
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stream_.write(text.c_str(), begin);
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// The key is between the {{ and }}.
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const std::string key = text.substr(begin + 2, end - begin - 2);
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// Find the value associated with the key. If it exists, write the
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// value into the stream, otherwise write the key itself into the stream.
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auto iter = value_map_.find(key);
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if (iter != value_map_.end()) {
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const std::string &value = iter->second;
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stream_ << value;
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} else {
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assert(false && "could not find key");
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stream_ << key;
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}
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// Update the text to everything after the }}.
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text = text.substr(end + 2);
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}
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if (!text.empty() && text.back() == '\\') {
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text.pop_back();
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stream_ << text;
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} else {
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stream_ << text << std::endl;
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}
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}
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const char *BaseGenerator::FlatBuffersGeneratedWarning() {
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return "automatically generated by the FlatBuffers compiler,"
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" do not modify\n\n";
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}
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std::string BaseGenerator::NamespaceDir(const Parser &parser,
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const std::string &path,
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const Namespace &ns) {
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EnsureDirExists(path.c_str());
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if (parser.opts.one_file) return path;
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std::string namespace_dir = path; // Either empty or ends in separator.
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auto &namespaces = ns.components;
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for (auto it = namespaces.begin(); it != namespaces.end(); ++it) {
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namespace_dir += *it + kPathSeparator;
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EnsureDirExists(namespace_dir.c_str());
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}
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return namespace_dir;
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}
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std::string BaseGenerator::NamespaceDir(const Namespace &ns) const {
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return BaseGenerator::NamespaceDir(parser_, path_, ns);
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}
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bool BaseGenerator::IsEverythingGenerated() const {
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for (auto it = parser_.enums_.vec.begin(); it != parser_.enums_.vec.end();
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++it) {
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if (!(*it)->generated) return false;
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}
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for (auto it = parser_.structs_.vec.begin();
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it != parser_.structs_.vec.end(); ++it) {
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if (!(*it)->generated) return false;
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}
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return true;
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}
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std::string BaseGenerator::FullNamespace(const char *separator,
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const Namespace &ns) {
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std::string namespace_name;
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auto &namespaces = ns.components;
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for (auto it = namespaces.begin(); it != namespaces.end(); ++it) {
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if (namespace_name.length()) namespace_name += separator;
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namespace_name += *it;
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}
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return namespace_name;
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}
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std::string BaseGenerator::LastNamespacePart(const Namespace &ns) {
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if (!ns.components.empty())
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return ns.components.back();
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else
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return std::string("");
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}
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// Ensure that a type is prefixed with its namespace whenever it is used
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// outside of its namespace.
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std::string BaseGenerator::WrapInNameSpace(const Namespace *ns,
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const std::string &name) const {
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if (CurrentNameSpace() == ns) return name;
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std::string qualified_name = qualifying_start_;
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for (auto it = ns->components.begin(); it != ns->components.end(); ++it)
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qualified_name += *it + qualifying_separator_;
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return qualified_name + name;
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}
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std::string BaseGenerator::WrapInNameSpace(const Definition &def) const {
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return WrapInNameSpace(def.defined_namespace, def.name);
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}
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// Generate a documentation comment, if available.
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void GenComment(const std::vector<std::string> &dc, std::string *code_ptr,
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const CommentConfig *config, const char *prefix) {
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if (dc.begin() == dc.end()) {
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// Don't output empty comment blocks with 0 lines of comment content.
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return;
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}
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std::string &code = *code_ptr;
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if (config != nullptr && config->first_line != nullptr) {
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code += std::string(prefix) + std::string(config->first_line) + "\n";
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}
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std::string line_prefix = std::string(prefix) +
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((config != nullptr && config->content_line_prefix != nullptr) ?
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config->content_line_prefix : "///");
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for (auto it = dc.begin();
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it != dc.end();
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++it) {
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code += line_prefix + *it + "\n";
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}
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if (config != nullptr && config->last_line != nullptr) {
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code += std::string(prefix) + std::string(config->last_line) + "\n";
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}
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}
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} // namespace flatbuffers
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