compilerplugins/clang/rendercontext.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #include <string>
  11 #include <iostream>
  12
  13 #include "plugin.hxx"
  14 #include "check.hxx"
  15 #include "clang/AST/CXXInheritance.h"
  16
  17 // Check for calls to OutputDevice methods that are not passing through RenderContext
  18
  19 namespace
  20 {
  21
  22 class RenderContext:
  23     public loplugin::FilteringPlugin<RenderContext>
  24 {
  25 public:
  26     explicit RenderContext(loplugin::InstantiationData const & data):
  27         FilteringPlugin(data) {}
  28
  29     virtual void run() override {
  30         TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
  31     }
  32
  33     bool TraverseFunctionDecl(const FunctionDecl * decl);
  34
  35     bool VisitCXXMemberCallExpr(const CXXMemberCallExpr *);
  36
  37 private:
  38     bool        mbChecking = false;
  39 };
  40
  41 // We use Traverse to set a flag so we can easily ignore certain method calls
  42 bool RenderContext::TraverseFunctionDecl(const FunctionDecl * pFunctionDecl)
  43 {
  44     if (ignoreLocation(pFunctionDecl)) {
  45         return true;
  46     }
  47     if (!pFunctionDecl->hasBody()) {
  48         return true;
  49     }
  50     if ( pFunctionDecl != pFunctionDecl->getCanonicalDecl() ) {
  51         return true;
  52     }
  53     // Ignore methods inside the OutputDevice class
  54     const CXXMethodDecl *pCXXMethodDecl = dyn_cast<CXXMethodDecl>(pFunctionDecl);
  55     if (pCXXMethodDecl) {
  56         if (loplugin::TypeCheck(pCXXMethodDecl->getParent()).Class("OutputDevice").GlobalNamespace())
  57             return true;
  58     }
  59     // we are only currently interested in methods where the first parameter is RenderContext
  60     if (pFunctionDecl->getNumParams() == 0)
  61         return true;
  62     if ( loplugin::TypeCheck(pFunctionDecl->getParamDecl( 0 )->getType()).Class("RenderContext").GlobalNamespace() ) {
  63         return true;
  64     }
  65     mbChecking = true;
  66     TraverseStmt(pFunctionDecl->getBody());
  67     mbChecking = false;
  68     return true;
  69 }
  70
  71 bool RenderContext::VisitCXXMemberCallExpr(const CXXMemberCallExpr* pCXXMemberCallExpr)
  72 {
  73     if (!mbChecking)
  74         return true;
  75     if (ignoreLocation(pCXXMemberCallExpr)) {
  76         return true;
  77     }
  78     const CXXRecordDecl *pCXXRecordDecl = pCXXMemberCallExpr->getRecordDecl();
  79     if (!loplugin::TypeCheck(pCXXRecordDecl).Class("OutputDevice").GlobalNamespace()) {
  80         return true;
  81     }
  82     // ignore a handful of methods. They will most probably still be present in Window for use during processing outside of the Paint()
  83     // method lifecycle
  84     const CXXMethodDecl *pCXXMethodDecl = pCXXMemberCallExpr->getMethodDecl();
  85     if (pCXXMethodDecl->isInstance()) {
  86         StringRef name = pCXXMethodDecl->getName();
  87         if (name == "LogicToPixel" || name == "GetMapMode" || name == "GetFontMetric" || name == "LogicToLogic"
  88             || name == "PixelToLogic" || name == "SetDigitLanguage")
  89         {
  90             return true;
  91         }
  92     }
  93     // for calling through a pointer
  94     const ImplicitCastExpr *pImplicitCastExpr = dyn_cast<ImplicitCastExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
  95     if (pImplicitCastExpr) {
  96         QualType aType = pImplicitCastExpr->getSubExpr()->getType();
  97         if (aType->isPointerType())
  98             aType = aType->getPointeeType();
  99         std::string t2 = aType.getAsString();
 100         if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
 101             return true;
 102     }
 103     // for calling through a reference
 104     const DeclRefExpr *pDeclRefExpr = dyn_cast<DeclRefExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
 105     if (pDeclRefExpr) {
 106         QualType aType = pDeclRefExpr->getType();
 107         std::string t2 = aType.getAsString();
 108         if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
 109             return true;
 110     }
 111     // for calling through a chain of methods
 112     const CXXMemberCallExpr *pMemberExpr = dyn_cast<CXXMemberCallExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
 113     if (pMemberExpr) {
 114         QualType aType = pMemberExpr->getType();
 115         if (aType->isPointerType())
 116             aType = aType->getPointeeType();
 117         std::string t2 = aType.getAsString();
 118         if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
 119             return true;
 120     }
 121     report(
 122         DiagnosticsEngine::Warning,
 123         "Should be calling OutputDevice method through RenderContext.",
 124         compat::getBeginLoc(pCXXMemberCallExpr))
 125             << pCXXMemberCallExpr->getSourceRange();
 126     return true;
 127 }
 128
 129 loplugin::Plugin::Registration< RenderContext > X("rendercontext", false);
 130
 131 }
 132
 133 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */