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 "compat.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 RecursiveASTVisitor<RenderContext>, public loplugin::Plugin
  24 {
  25 public:
  26     explicit RenderContext(InstantiationData const & data): Plugin(data) {}
  27
  28     virtual void run() override {
  29         TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
  30     }
  31
  32     bool TraverseFunctionDecl(const FunctionDecl * decl);
  33
  34     bool VisitCXXMemberCallExpr(const CXXMemberCallExpr *);
  35
  36 private:
  37     bool        mbChecking = false;
  38 };
  39
  40 // We use Traverse to set a flag so we can easily ignore certain method calls
  41 bool RenderContext::TraverseFunctionDecl(const FunctionDecl * pFunctionDecl)
  42 {
  43     if (ignoreLocation(pFunctionDecl)) {
  44         return true;
  45     }
  46     if (!pFunctionDecl->hasBody()) {
  47         return true;
  48     }
  49     if ( pFunctionDecl != pFunctionDecl->getCanonicalDecl() ) {
  50         return true;
  51     }
  52     // Ignore methods inside the OutputDevice class
  53     const CXXMethodDecl *pCXXMethodDecl = dyn_cast<CXXMethodDecl>(pFunctionDecl);
  54     if (pCXXMethodDecl) {
  55         std::string aParentName = pCXXMethodDecl->getParent()->getQualifiedNameAsString();
  56         if (aParentName == "OutputDevice")
  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     string arg0 = pFunctionDecl->getParamDecl( 0 )->getType().getAsString();
  63     if ( arg0.find("RenderContext") != std::string::npos ) {
  64         return true;
  65     }
  66     mbChecking = true;
  67     TraverseStmt(pFunctionDecl->getBody());
  68     mbChecking = false;
  69     return true;
  70 }
  71
  72 bool RenderContext::VisitCXXMemberCallExpr(const CXXMemberCallExpr* pCXXMemberCallExpr)
  73 {
  74     if (!mbChecking)
  75         return true;
  76     if (ignoreLocation(pCXXMemberCallExpr)) {
  77         return true;
  78     }
  79     const CXXRecordDecl *pCXXRecordDecl = pCXXMemberCallExpr->getRecordDecl();
  80     if (pCXXRecordDecl->getQualifiedNameAsString() != "OutputDevice") {
  81         return true;
  82     }
  83     // ignore a handful of methods. They will most probably still be present in Window for use during processing outside of the Paint()
  84     // method lifecycle
  85     const CXXMethodDecl *pCXXMethodDecl = pCXXMemberCallExpr->getMethodDecl();
  86     if (pCXXMethodDecl->isInstance()) {
  87         StringRef name = pCXXMethodDecl->getName();
  88         if (name == "LogicToPixel" || name == "GetMapMode" || name == "GetFontMetric" || name == "LogicToLogic"
  89             || name == "PixelToLogic" || name == "SetDigitLanguage")
  90         {
  91             return true;
  92         }
  93     }
  94     // for calling through a pointer
  95     const ImplicitCastExpr *pImplicitCastExpr = dyn_cast<ImplicitCastExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
  96     std::string x = "0"; // for debugging
  97     if (pImplicitCastExpr) {
  98         x += "1";
  99         QualType aType = pImplicitCastExpr->getSubExpr()->getType();
 100         if (aType->isPointerType())
 101             aType = aType->getPointeeType();
 102         std::string t2 = aType.getAsString();
 103         if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
 104             return true;
 105     }
 106     // for calling through a reference
 107     const DeclRefExpr *pDeclRefExpr = dyn_cast<DeclRefExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
 108     if (pDeclRefExpr) {
 109         x += "2";
 110         QualType aType = pDeclRefExpr->getType();
 111         std::string t2 = aType.getAsString();
 112         if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
 113             return true;
 114     }
 115     // for calling through a chain of methods
 116     const CXXMemberCallExpr *pMemberExpr = dyn_cast<CXXMemberCallExpr>(pCXXMemberCallExpr->getImplicitObjectArgument());
 117     if (pMemberExpr) {
 118         x += "3";
 119         QualType aType = pMemberExpr->getType();
 120         if (aType->isPointerType())
 121             aType = aType->getPointeeType();
 122         std::string t2 = aType.getAsString();
 123         x += t2;
 124         if (t2 == "vcl::RenderContext" || t2 == "const vcl::RenderContext")
 125             return true;
 126     }
 127     report(
 128         DiagnosticsEngine::Warning,
 129         //  + x + pCXXMemberCallExpr->getImplicitObjectArgument()->getStmtClassName()
 130         "Should be calling OutputDevice method through RenderContext.",
 131         pCXXMemberCallExpr->getLocStart())
 132             << pCXXMemberCallExpr->getSourceRange();
 133     return true;
 134 }
 135
 136 loplugin::Plugin::Registration< RenderContext > X("rendercontext", false);
 137
 138 }
 139
 140 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */