1 files changed, 133 insertions, 0 deletions
diff --git a/compilerplugins/clang/rendercontext.cxx b/compilerplugins/clang/rendercontext.cxx
new file mode 100644
index 000000000..2508b449e
--- /dev/null
+++ b/compilerplugins/clang/rendercontext.cxx
@@ -0,0 +1,133 @@
+/* -*- 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 <iostream>
+
+#include "plugin.hxx"
+#include "check.hxx"
+#include "clang/AST/CXXInheritance.h"
+
+// Check for calls to OutputDevice methods that are not passing through RenderContext
+
+namespace
+{
+
+class RenderContext:
+    public loplugin::FilteringPlugin<RenderContext>
+{
+public:
+    explicit RenderContext(loplugin::InstantiationData const & data):
+        FilteringPlugin(data) {}
+
+    virtual void run() override {
+        TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+    }
+
+    bool TraverseFunctionDecl(const FunctionDecl * decl);
+
+    bool VisitCXXMemberCallExpr(const CXXMemberCallExpr *);
+
+private:
+    bool        mbChecking = false;
+};
+
+// We use Traverse to set a flag so we can easily ignore certain method calls
+bool RenderContext::TraverseFunctionDecl(const FunctionDecl * pFunctionDecl)
+{
+    if (ignoreLocation(pFunctionDecl)) {
+        return true;
+    }
+    if (!pFunctionDecl->hasBody()) {
+        return true;
+    }
+    if ( pFunctionDecl != pFunctionDecl->getCanonicalDecl() ) {
+        return true;
+    }
+    // Ignore methods inside the OutputDevice class
+    const CXXMethodDecl *pCXXMethodDecl = dyn_cast<CXXMethodDecl>(pFunctionDecl);
+    if (pCXXMethodDecl) {
+        if (loplugin::TypeCheck(pCXXMethodDecl->getParent()).Class("OutputDevice").GlobalNamespace())
+            return true;
+    }
+    // we are only currently interested in methods where the first parameter is RenderContext
+    if (pFunctionDecl->getNumParams() == 0)
+        return true;
+    if ( loplugin::TypeCheck(pFunctionDecl->getParamDecl( 0 )->getType()).Class("RenderContext").GlobalNamespace() ) {
+        return true;
+    }
+    mbChecking = true;
+    TraverseStmt(pFunctionDecl->getBody());
+    mbChecking = false;
+    return true;
+}
+
+bool RenderContext::VisitCXXMemberCallExpr(const CXXMemberCallExpr* pCXXMemberCallExpr)
+{
+    if (!mbChecking)
+        return true;
+    if (ignoreLocation(pCXXMemberCallExpr)) {
+        return true;
+    }
+    const CXXRecordDecl *pCXXRecordDecl = pCXXMemberCallExpr->getRecordDecl();
+    if (!loplugin::TypeCheck(pCXXRecordDecl).Class("OutputDevice").GlobalNamespace()) {
+        return true;
+    }
+    // ignore a handful of methods. They will most probably still be present in Window for use during processing outside of the Paint()
+    // method lifecycle
+    const CXXMethodDecl *pCXXMethodDecl = pCXXMemberCallExpr->getMethodDecl();
+    if (pCXXMethodDecl->isInstance()) {
+        StringRef name = pCXXMethodDecl->getName();
+        if (name == "LogicToPixel" || name == "GetMapMode" || name == "GetFontMetric" || name == "LogicToLogic"
+            || name == "PixelToLogic" || name == "SetDigitLanguage")
+        {
+            return true;
+        }
+    }
+    // for calling through a pointer
+    const ImplicitCastExpr *pImplicitCastExpr = dyn_cast<ImplicitCastExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
+    if (pImplicitCastExpr) {
+        QualType aType = pImplicitCastExpr->getSubExpr()->getType();
+        if (aType->isPointerType())
+            aType = aType->getPointeeType();
+        std::string t2 = aType.getAsString();
+        if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
+            return true;
+    }
+    // for calling through a reference
+    const DeclRefExpr *pDeclRefExpr = dyn_cast<DeclRefExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
+    if (pDeclRefExpr) {
+        QualType aType = pDeclRefExpr->getType();
+        std::string t2 = aType.getAsString();
+        if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
+            return true;
+    }
+    // for calling through a chain of methods
+    const CXXMemberCallExpr *pMemberExpr = dyn_cast<CXXMemberCallExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
+    if (pMemberExpr) {
+        QualType aType = pMemberExpr->getType();
+        if (aType->isPointerType())
+            aType = aType->getPointeeType();
+        std::string t2 = aType.getAsString();
+        if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
+            return true;
+    }
+    report(
+        DiagnosticsEngine::Warning,
+        "Should be calling OutputDevice method through RenderContext.",
+        pCXXMemberCallExpr->getBeginLoc())
+            << pCXXMemberCallExpr->getSourceRange();
+    return true;
+}
+
+loplugin::Plugin::Registration< RenderContext > X("rendercontext", false);
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */