new loplugin:deadclass

look for classes which only have copy/move constructors, and so are
effectively dead

Change-Id: I0b844f301e2200c2b40031856bfdb0b0e2c8f77d
Reviewed-on: https://gerrit.libreoffice.org/41039Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

basic/source/sbx/sbxvar.cxx

@@ -624,62 +624,6 @@ SbxInfo::SbxInfo( const OUString& r, sal_uInt32 n )
        : aHelpFile( r ), nHelpId( n )
 {}
 
-// SbxAlias
-
-SbxAlias::SbxAlias( const SbxAlias& r )
-        : SvRefBase( r ), SbxVariable( r ),
-          SfxListener( r ), xAlias( r.xAlias )
-{}
-
-SbxAlias& SbxAlias::operator=( const SbxAlias& r )
-{
-    xAlias = r.xAlias;
-    return *this;
-}
-
-SbxAlias::~SbxAlias()
-{
-    if( xAlias.is() )
-    {
-        EndListening( xAlias->GetBroadcaster() );
-    }
-}
-
-void SbxAlias::Broadcast( SfxHintId nHt )
-{
-    if( xAlias.is() )
-    {
-        xAlias->SetParameters( GetParameters() );
-        if( nHt == SfxHintId::BasicDataWanted )
-        {
-            SbxVariable::operator=( *xAlias );
-        }
-        else if( nHt == SfxHintId::BasicDataChanged || nHt == SfxHintId::BasicConverted )
-        {
-            *xAlias = *this;
-        }
-        else if( nHt == SfxHintId::BasicInfoWanted )
-        {
-            xAlias->Broadcast( nHt );
-            pInfo = xAlias->GetInfo();
-        }
-    }
-}
-
-void SbxAlias::Notify( SfxBroadcaster&, const SfxHint& rHint )
-{
-    const SbxHint* p = dynamic_cast<const SbxHint*>(&rHint);
-    if( p && p->GetId() == SfxHintId::BasicDying )
-    {
-        xAlias.clear();
-        // delete the alias?
-        if( pParent )
-        {
-            pParent->Remove( this );
-        }
-    }
-}
-
 void SbxVariable::Dump( SvStream& rStrm, bool bFill )
 {
     OString aBNameStr(OUStringToOString(GetName( SbxNameType::ShortTypes ), RTL_TEXTENCODING_ASCII_US));

compilerplugins/clang/deadclass.cxx

+/* -*- 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 "plugin.hxx"
+
+namespace {
+
+class DeadClass:
+    public RecursiveASTVisitor<DeadClass>, public loplugin::Plugin
+{
+public:
+    explicit DeadClass(InstantiationData const & data): Plugin(data) {}
+
+    void run() override;
+
+    bool VisitCXXRecordDecl(CXXRecordDecl const *);
+};
+
+void DeadClass::run() {
+    if (compiler.getLangOpts().CPlusPlus) {
+        TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+    }
+}
+
+bool DeadClass::VisitCXXRecordDecl(CXXRecordDecl const * decl) {
+    if (ignoreLocation(decl) || !decl->isThisDeclarationADefinition())
+        return true;
+    if (decl->needsImplicitDefaultConstructor())
+        return true;
+    if (decl->getDescribedClassTemplate())
+        return true;
+    if (isa<ClassTemplateSpecializationDecl>(decl))
+        return true;
+    int otherCnt = 0;
+    int copyMoveCnt = 0;
+    for (auto i = decl->ctor_begin(); i != decl->ctor_end(); ++i) {
+        if (!i->isUserProvided())
+            continue;
+//        if (i->getTemplatedKind() != clang::FunctionDecl::TK_NonTemplate)
+//            return true;
+//        if (i->getTemplateInstantiationPattern())
+//            return true;
+        if (i->isCopyOrMoveConstructor())
+            copyMoveCnt++;
+        else
+            otherCnt++;
+    }
+    if (otherCnt == 0 && copyMoveCnt > 0)
+    {
+        report(
+            DiagnosticsEngine::Warning,
+            "class has only copy/move constructors, must be dead",
+            decl->getLocStart())
+            << decl->getSourceRange();
+        for (auto i = decl->ctor_begin(); i != decl->ctor_end(); ++i) {
+            if (i->isDeleted())
+                continue;
+            i->dump();
+        }
+    }
+    return true;
+}
+
+loplugin::Plugin::Registration<DeadClass> X("deadclass");
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */

compilerplugins/clang/test/deadclass.cxx

+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * 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/.
+ */
+
+struct Foo { // expected-error {{class has only copy/move constructors, must be dead [loplugin:deadclass]}}
+    Foo(Foo&);
+};
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */

include/basic/sbx.hxx

@@ -97,18 +97,6 @@ public:
     SbxVariable* GetVar() const { return pVar; }
 };
 
-// SbxAlias is an alias for a var or object
-class BASIC_DLLPUBLIC SbxAlias : public SbxVariable, public SfxListener
-{
-    SbxVariableRef xAlias;
-    virtual ~SbxAlias() override;
-    virtual void Broadcast( SfxHintId ) override;
-    virtual void Notify( SfxBroadcaster& rBC, const SfxHint& rHint ) override;
-public:
-    SbxAlias( const SbxAlias& );
-    SbxAlias& operator=( const SbxAlias& );
-};
-
 // SbxArray is an unidimensional, dynamic Array
 // The variables convert from SbxVariablen. Put()/Insert() into the
 // declared datatype, if they are not SbxVARIANT.

sc/source/filter/inc/biffcodec.hxx

@@ -54,43 +54,6 @@ private:
     bool                mbValid;        /// True = decoder is correctly initialized.
 };
 
-/** Decodes BIFF stream contents that are encoded using the old XOR algorithm. */
-class BiffDecoder_XOR : public BiffDecoderBase
-{
-private:
-    /** Copy constructor for cloning. */
-                        BiffDecoder_XOR( const BiffDecoder_XOR& rDecoder );
-
-    /** Implements password verification and initialization of the decoder. */
-    virtual css::uno::Sequence< css::beans::NamedValue > implVerifyPassword( const OUString& rPassword ) override;
-    virtual bool implVerifyEncryptionData( const css::uno::Sequence< css::beans::NamedValue >& rEncryptionData ) override;
-
-private:
-    ::oox::core::BinaryCodec_XOR maCodec;   /// Cipher algorithm implementation.
-    css::uno::Sequence< css::beans::NamedValue > maEncryptionData;
-    sal_uInt16          mnKey;
-    sal_uInt16          mnHash;
-};
-
-/** Decodes BIFF stream contents that are encoded using the RC4 algorithm. */
-class BiffDecoder_RCF : public BiffDecoderBase
-{
-private:
-    /** Copy constructor for cloning. */
-                        BiffDecoder_RCF( const BiffDecoder_RCF& rDecoder );
-
-    /** Implements password verification and initialization of the decoder. */
-    virtual css::uno::Sequence< css::beans::NamedValue > implVerifyPassword( const OUString& rPassword ) override;
-    virtual bool implVerifyEncryptionData( const css::uno::Sequence< css::beans::NamedValue >& rEncryptionData ) override;
-
-private:
-    ::oox::core::BinaryCodec_RCF maCodec;   /// Cipher algorithm implementation.
-    css::uno::Sequence< css::beans::NamedValue > maEncryptionData;
-    ::std::vector< sal_uInt8 > maSalt;
-    ::std::vector< sal_uInt8 > maVerifier;
-    ::std::vector< sal_uInt8 > maVerifierHash;
-};
-
 } // namespace xls
 } // namespace oox
 

sc/source/filter/oox/biffcodec.cxx

@@ -52,105 +52,6 @@ BiffDecoderBase::~BiffDecoderBase()
     return mbValid ? ::comphelper::DocPasswordVerifierResult::OK : ::comphelper::DocPasswordVerifierResult::WrongPassword;
 }
 
-BiffDecoder_XOR::BiffDecoder_XOR( const BiffDecoder_XOR& rDecoder ) :
-    BiffDecoderBase(),  // must be called to prevent compiler warning
-    maCodec(),
-    maEncryptionData( rDecoder.maEncryptionData ),
-    mnKey( rDecoder.mnKey ),
-    mnHash( rDecoder.mnHash )
-{
-    if( isValid() )
-        maCodec.initCodec( maEncryptionData );
-}
-
-Sequence< NamedValue > BiffDecoder_XOR::implVerifyPassword( const OUString& rPassword )
-{
-    maEncryptionData.realloc( 0 );
-
-    /*  Convert password to a byte string. TODO: this needs some finetuning
-        according to the spec... */
-    OString aBytePassword = OUStringToOString( rPassword, osl_getThreadTextEncoding() );
-    sal_Int32 nLen = aBytePassword.getLength();
-    if( (0 < nLen) && (nLen < 16) )
-    {
-        // init codec
-        maCodec.initKey( reinterpret_cast< const sal_uInt8* >( aBytePassword.getStr() ) );
-
-        if( maCodec.verifyKey( mnKey, mnHash ) )
-            maEncryptionData = maCodec.getEncryptionData();
-    }
-
-    return maEncryptionData;
-}
-
-bool BiffDecoder_XOR::implVerifyEncryptionData( const Sequence< NamedValue >& rEncryptionData )
-{
-    maEncryptionData.realloc( 0 );
-
-    if( rEncryptionData.hasElements() )
-    {
-        // init codec
-        maCodec.initCodec( rEncryptionData );
-
-        if( maCodec.verifyKey( mnKey, mnHash ) )
-            maEncryptionData = rEncryptionData;
-    }
-
-    return maEncryptionData.hasElements();
-}
-
-
-BiffDecoder_RCF::BiffDecoder_RCF( const BiffDecoder_RCF& rDecoder ) :
-    BiffDecoderBase(),  // must be called to prevent compiler warning
-    maEncryptionData( rDecoder.maEncryptionData ),
-    maSalt( rDecoder.maSalt ),
-    maVerifier( rDecoder.maVerifier ),
-    maVerifierHash( rDecoder.maVerifierHash )
-{
-    if( isValid() )
-        maCodec.initCodec( maEncryptionData );
-}
-
-Sequence< NamedValue > BiffDecoder_RCF::implVerifyPassword( const OUString& rPassword )
-{
-    maEncryptionData.realloc( 0 );
-
-    sal_Int32 nLen = rPassword.getLength();
-    if( (0 < nLen) && (nLen < 16) )
-    {
-        // copy string to sal_uInt16 array
-        ::std::vector< sal_uInt16 > aPassVect( 16 );
-        const sal_Unicode* pcChar = rPassword.getStr();
-        const sal_Unicode* pcCharEnd = pcChar + nLen;
-        ::std::vector< sal_uInt16 >::iterator aIt = aPassVect.begin();
-        for( ; pcChar < pcCharEnd; ++pcChar, ++aIt )
-            *aIt = static_cast< sal_uInt16 >( *pcChar );
-
-        // init codec
-        maCodec.initKey(aPassVect.data(), maSalt.data());
-        if (maCodec.verifyKey(maVerifier.data(), maVerifierHash.data()))
-            maEncryptionData = maCodec.getEncryptionData();
-    }
-
-    return maEncryptionData;
-}
-
-bool BiffDecoder_RCF::implVerifyEncryptionData( const Sequence< NamedValue >& rEncryptionData )
-{
-    maEncryptionData.realloc( 0 );
-
-    if( rEncryptionData.hasElements() )
-    {
-        // init codec
-        maCodec.initCodec( rEncryptionData );
-
-        if (maCodec.verifyKey(maVerifier.data(), maVerifierHash.data()))
-            maEncryptionData = rEncryptionData;
-    }
-
-    return maEncryptionData.hasElements();
-}
-
 } // namespace xls
 } // namespace oox
 

solenv/CompilerTest_compilerplugins_clang.mk

@@ -13,6 +13,7 @@ $(eval $(call gb_CompilerTest_add_exception_objects,compilerplugins_clang, \
     compilerplugins/clang/test/casttovoid \
     compilerplugins/clang/test/constparams \
     compilerplugins/clang/test/cppunitassertequals \
+    compilerplugins/clang/test/deadclass \
     compilerplugins/clang/test/datamembershadow \
     compilerplugins/clang/test/externvar \
     compilerplugins/clang/test/finalprotected \