compilerplugins/clang/unoquery.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
   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 #ifndef LO_CLANG_SHARED_PLUGINS
  11
  12 #include "check.hxx"
  13 #include "plugin.hxx"
  14
  15 // TODO it would be better if we were running some kind of nullability analysis here, where we marked
  16 // the results of expressions like Reference(..UNO_QUERY) as being nullable, and then looked for
  17 // places where we unconditionally dereference the results of that expression.
  18
  19 namespace
  20 {
  21 class UnoQuery : public loplugin::FilteringPlugin<UnoQuery>
  22 {
  23 public:
  24     explicit UnoQuery(loplugin::InstantiationData const& data)
  25         : FilteringPlugin(data)
  26     {
  27     }
  28
  29     bool preRun() override { return compiler.getLangOpts().CPlusPlus; }
  30
  31     void run() override
  32     {
  33         if (preRun())
  34         {
  35             TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
  36         }
  37     }
  38
  39     bool VisitCXXMemberCallExpr(CXXMemberCallExpr const*);
  40 };
  41
  42 bool UnoQuery::VisitCXXMemberCallExpr(CXXMemberCallExpr const* memberCallExpr)
  43 {
  44     if (ignoreLocation(memberCallExpr))
  45         return true;
  46
  47     auto isXInterface = [](Decl const* decl) -> bool {
  48         return bool(loplugin::DeclCheck(decl)
  49                         .Class("XInterface")
  50                         .Namespace("uno")
  51                         .Namespace("star")
  52                         .Namespace("sun")
  53                         .Namespace("com")
  54                         .GlobalNamespace());
  55     };
  56     if (!loplugin::isDerivedFrom(memberCallExpr->getRecordDecl(), isXInterface))
  57         return true;
  58     auto operatorCallExpr = dyn_cast<CXXOperatorCallExpr>(
  59         memberCallExpr->getImplicitObjectArgument()->IgnoreImplicit());
  60     if (!operatorCallExpr)
  61         return true;
  62
  63     Expr const* expr = operatorCallExpr->getArg(0)->IgnoreImplicit();
  64     // depending on the version of clang, the IgnoreImplicit may or may not look through these nodes
  65     if (auto matTemp = dyn_cast<MaterializeTemporaryExpr>(expr))
  66         expr = matTemp->getSubExpr();
  67     if (auto bindTemp = dyn_cast<CXXBindTemporaryExpr>(expr))
  68         expr = bindTemp->getSubExpr();
  69
  70     auto temporaryExpr = dyn_cast<CXXTemporaryObjectExpr>(expr);
  71     if (!temporaryExpr)
  72         return true;
  73     if (temporaryExpr->getNumArgs() < 2)
  74         return true;
  75     auto declRefExpr = dyn_cast<DeclRefExpr>(temporaryExpr->getArg(1)->IgnoreImplicit());
  76     if (!declRefExpr)
  77         return true;
  78     auto enumConstant = dyn_cast<EnumConstantDecl>(declRefExpr->getDecl());
  79     if (!enumConstant)
  80         return true;
  81     if (enumConstant->getName() != "UNO_QUERY")
  82         return true;
  83
  84     report(DiagnosticsEngine::Warning,
  85            "calling UNO_QUERY followed by unconditional method call might result in SIGSEGV, "
  86            "rather use UNO_QUERY_THROW",
  87            memberCallExpr->getExprLoc())
  88         << memberCallExpr->getSourceRange();
  89
  90     return true;
  91 }
  92
  93 loplugin::Plugin::Registration<UnoQuery> unoquery("unoquery");
  94
  95 } // namespace
  96
  97 #endif // LO_CLANG_SHARED_PLUGINS
  98
  99 /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */