Adding upstream version 4:7.4.7.upstream/4%7.4.7upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 138 insertions, 0 deletions

diff --git a/compilerplugins/clang/store/returnbyref.cxx b/compilerplugins/clang/store/returnbyref.cxx
new file mode 100644
index 000000000..d4049481a
--- /dev/null
+++ b/compilerplugins/clang/store/returnbyref.cxx
@@ -0,0 +1,138 @@
+/* -*- 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 <set>
+
+#include "plugin.hxx"
+
+// Find places where we are returning a pointer to something, where we can be returning a reference.
+// e.g.
+//   class A {
+//     struct X x;
+//     public:
+//     X* getX() { return &x; }
+//   }
+// which can be:
+//     X& getX() { return x; }
+
+namespace {
+
+class ReturnByRef:
+    public loplugin::FilteringPlugin<ReturnByRef>
+{
+public:
+    explicit ReturnByRef(InstantiationData const & data): FilteringPlugin(data) {}
+
+    virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
+
+    bool VisitCXXMethodDecl(const CXXMethodDecl * decl);
+private:
+    std::string getFilename(SourceLocation loc);
+};
+
+bool ReturnByRef::VisitCXXMethodDecl(const CXXMethodDecl * functionDecl) {
+    if (ignoreLocation(functionDecl)) {
+        return true;
+    }
+    if (functionDecl->isVirtual()) {
+        return true;
+    }
+    if (!functionDecl->isInstance()) {
+        return true;
+    }
+    if (!functionDecl->hasBody()) {
+        return true;
+    }
+    // ignore stuff that forms part of the stable URE interface
+    if (isInUnoIncludeFile(functionDecl)) {
+        return true;
+    }
+    QualType t1 { functionDecl->getReturnType() };
+    if (!t1->isPointerType()) {
+        return true;
+    }
+    // Ignore stuff like:
+    //   operator vcl::Window *(){ return &m_rWindow; }
+    if (dyn_cast< CXXConversionDecl >( functionDecl ) != nullptr) {
+        return true;
+    }
+
+    std::string aFilename = getFilename(functionDecl->getCanonicalDecl()->getLocStart());
+    if (aFilename == SRCDIR "/include/o3tl/cow_wrapper.hxx")
+    {
+        return true;
+    }
+    if ( functionDecl->getNameAsString() == "operator->") {
+        return true;
+    }
+    std::string aFunctionName = functionDecl->getQualifiedNameAsString();
+    if (aFunctionName == "SbxValue::data") {
+        return true;
+    }
+    /*
+    std::string aParentName = functionDecl->getParent()->getQualifiedNameAsString();
+    std::string fqn = aParentName + "::" + functionDecl->getNameAsString();
+    if (aFilename == "TextCharAttribList::GetAttrib") {
+        return true;
+    }*/
+
+    /*
+      The AST here looks like:
+      -CompoundStmt
+       `-ReturnStmt
+          `-UnaryOperator
+    */
+
+    const CompoundStmt* compoundStmt = dyn_cast< CompoundStmt >( functionDecl->getBody() );
+    if (compoundStmt == nullptr || compoundStmt->body_begin() == compoundStmt->body_end()) {
+        return true;
+    }
+    const ReturnStmt* returnStmt = dyn_cast<ReturnStmt>(*compoundStmt->child_begin());
+    if (returnStmt == nullptr) {
+        return true;
+    }
+
+    const Stmt* nextStmt = dyn_cast<Expr>(*returnStmt->child_begin())->IgnoreParens();
+    const UnaryOperator* unaryOperator = dyn_cast<UnaryOperator>(nextStmt);
+    if (unaryOperator == nullptr || unaryOperator->getOpcode() != UO_AddrOf) {
+        return true;
+    }
+nextStmt->dump();
+    report(
+        DiagnosticsEngine::Warning,
+        "rather return by reference ",
+        functionDecl->getSourceRange().getBegin())
+      << functionDecl->getSourceRange();
+
+    // display the location of the class member declaration so I don't have to search for it by hand
+    auto otherLoc = functionDecl->getCanonicalDecl()->getSourceRange().getBegin();
+    if (otherLoc != functionDecl->getSourceRange().getBegin())
+    {
+        report(
+            DiagnosticsEngine::Note,
+            "rather return by reference",
+            functionDecl->getCanonicalDecl()->getSourceRange().getBegin())
+          << functionDecl->getCanonicalDecl()->getSourceRange();
+    }
+
+    return true;
+}
+
+std::string ReturnByRef::getFilename(SourceLocation loc)
+{
+    SourceLocation spellingLocation = compiler.getSourceManager().getSpellingLoc(loc);
+    return getFilenameOfLocation(spellingLocation);
+}
+
+loplugin::Plugin::Registration< ReturnByRef > X("returnbyref");
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */