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