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Diffstat (limited to 'compilerplugins/clang/passstringbyref.cxx')
-rw-r--r-- | compilerplugins/clang/passstringbyref.cxx | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/compilerplugins/clang/passstringbyref.cxx b/compilerplugins/clang/passstringbyref.cxx new file mode 100644 index 000000000000..610796936493 --- /dev/null +++ b/compilerplugins/clang/passstringbyref.cxx @@ -0,0 +1,71 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + */ + +#include <string> + +#include "plugin.hxx" + +// Find places where OUString and OString are passed by value. +// It's not very efficient, because we generally end up copying it twice - once into the parameter and +// again into the destination OUString. +// They should rather be passed by reference. + +namespace { + +class PassStringByRef: + public RecursiveASTVisitor<PassStringByRef>, public loplugin::Plugin +{ +public: + explicit PassStringByRef(InstantiationData const & data): Plugin(data) {} + + virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); } + + bool VisitFunctionDecl(const FunctionDecl * decl); +}; + +bool PassStringByRef::VisitFunctionDecl(const FunctionDecl * functionDecl) { + if (ignoreLocation(functionDecl)) { + return true; + } + // only warn on the definition/prototype of the function, + // not on the function implementation + if (functionDecl->isThisDeclarationADefinition() && functionDecl->getPreviousDecl() != nullptr) { + return true; + } + unsigned n = functionDecl->getNumParams(); + for (unsigned i = 0; i != n; ++i) { + const ParmVarDecl * pvDecl = functionDecl->getParamDecl(i); + QualType t1 { pvDecl->getType() }; + if (!t1->isClassType()) { + continue; + } + string typeName = t1.getUnqualifiedType().getCanonicalType().getAsString(); + if (typeName == "class rtl::OUString") { + report( + DiagnosticsEngine::Warning, + "passing OUString by value, rather pass by reference", + pvDecl->getSourceRange().getBegin()) + << pvDecl->getSourceRange(); + } + else if (typeName == "class rtl::OString") { + report( + DiagnosticsEngine::Warning, + "passing OString by value, rather pass by reference", + pvDecl->getSourceRange().getBegin()) + << pvDecl->getSourceRange(); + } + } + return true; +} + +loplugin::Plugin::Registration< PassStringByRef > X("passstringbyref"); + +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |