compilerplugins/clang/store/rtlconstasciimacro.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  * Based on LLVM/Clang.
   6  *
   7  * This file is distributed under the University of Illinois Open Source
   8  * License. See LICENSE.TXT for details.
   9  *
  10  */
  11
  12 /*
  13 This is a rewriter.
  14
  15 Remove uses of the macro RTL_CONSTASCII_USTRINGPARAM. One run is for one
  16 specific use (see below), modify source to remove other uses.
  17 */
  18
  19 #include "plugin.hxx"
  20
  21 #include <clang/Lex/Preprocessor.h>
  22
  23 namespace loplugin
  24 {
  25
  26 class RtlConstAsciiMacro
  27     : public loplugin::FilteringRewritePlugin< RtlConstAsciiMacro >
  28     , public PPCallbacks
  29     {
  30     public:
  31         explicit RtlConstAsciiMacro( const InstantiationData& data );
  32         virtual void run() override;
  33         bool VisitCXXConstructExpr( CXXConstructExpr* expr );
  34         bool VisitCXXTemporaryObjectExpr( CXXTemporaryObjectExpr* expr );
  35         bool VisitStringLiteral( const StringLiteral* literal );
  36         virtual void MacroExpands( const Token& macro, const MacroDirective* directive,
  37             SourceRange range, const MacroArgs* args ) override;
  38         enum { isPPCallback = true };
  39     private:
  40         map< SourceLocation, SourceLocation > expansions; // start location -> end location
  41         bool searchingForString;
  42         bool suitableString;
  43     };
  44
  45 RtlConstAsciiMacro::RtlConstAsciiMacro( const InstantiationData& data )
  46     : FilteringRewritePlugin( data )
  47     , searchingForString( false )
  48     {
  49     compiler.getPreprocessor().addPPCallbacks( this );
  50     }
  51
  52 void RtlConstAsciiMacro::run()
  53     {
  54     TraverseDecl( compiler.getASTContext().getTranslationUnitDecl());
  55     }
  56
  57 void RtlConstAsciiMacro::MacroExpands( const Token& macro, const MacroDirective*,
  58     SourceRange range, const MacroArgs* )
  59     {
  60     if( macro.getIdentifierInfo()->getName() != "RTL_CONSTASCII_USTRINGPARAM" )
  61         return;
  62     expansions[ range.getBegin() ] = range.getEnd();
  63     }
  64
  65 /* Remove use with the following ctor:
  66     OUString( const sal_Char * value, sal_Int32 length,
  67               rtl_TextEncoding encoding,
  68               sal_uInt32 convertFlags = OSTRING_TO_OUSTRING_CVTFLAGS )
  69    This means searching for CXXConstructExpr.
  70    For removal when used with functions it should check e.g. for CallExpr.
  71 */
  72 bool RtlConstAsciiMacro::VisitCXXConstructExpr( CXXConstructExpr* expr )
  73     {
  74     if( ignoreLocation( expr ))
  75         return true;
  76     if( expr->getNumArgs() != 4 )
  77         return true;
  78     // The last argument should be the default one when the macro is used.
  79     if( dyn_cast< CXXDefaultArgExpr >( expr->getArg( 3 )) == NULL )
  80         return true;
  81     if( expr->getConstructor()->getQualifiedNameAsString() != "rtl::OUString::OUString" )
  82         return true;
  83     const SourceManager& src = compiler.getSourceManager();
  84     SourceLocation start = src.getExpansionLoc( expr->getArg( 0 )->getLocStart());
  85     // Macro fills in the first 3 arguments, so they must all come from the same expansion.
  86     if( start != src.getExpansionLoc( expr->getArg( 2 )->getLocEnd()))
  87         return true;
  88     if( expansions.find( start ) == expansions.end())
  89         return true;
  90     SourceLocation end = expansions[ start ];
  91     // Remove the location, since sometimes the same code may be processed more than once
  92     // (e.g. non-trivial default arguments).
  93     expansions.erase( start );
  94     // Check if the string argument to the macro is suitable.
  95     searchingForString = true;
  96     suitableString = false;
  97     TraverseStmt( expr->getArg( 0 ));
  98     searchingForString = false;
  99     if( !suitableString )
 100         return true;
 101     // Search for '(' (don't just remove a given length to handle possible whitespace).
 102     const char* text = compiler.getSourceManager().getCharacterData( start );
 103     const char* pos = text;
 104     while( *pos != '(' )
 105         ++pos;
 106     ++pos;
 107     if( text[ -1 ] == ' ' && *pos == ' ' )
 108         ++pos; // do not leave two spaces
 109     removeText( start, pos - text, RemoveLineIfEmpty );
 110     const char* textend = compiler.getSourceManager().getCharacterData( end );
 111     if( textend[ -1 ] == ' ' && textend[ 1 ] == ' ' )
 112         removeText( end, 2, RemoveLineIfEmpty ); // Remove ') '.
 113     else
 114         removeText( end, 1, RemoveLineIfEmpty ); // Remove ')'.
 115     return true;
 116     }
 117
 118 bool RtlConstAsciiMacro::VisitCXXTemporaryObjectExpr( CXXTemporaryObjectExpr* expr )
 119     {
 120     return VisitCXXConstructExpr( expr );
 121     }
 122
 123 bool RtlConstAsciiMacro::VisitStringLiteral( const StringLiteral* literal )
 124     {
 125     if( !searchingForString )
 126         return true;
 127     if( suitableString ) // two string literals?
 128         {
 129         report( DiagnosticsEngine::Warning, "cannot analyze RTL_CONSTASCII_USTRINGPARAM (plugin needs fixing)" )
 130             << literal->getSourceRange();
 131         return true;
 132         }
 133     if( !literal->isAscii()) // ignore
 134         return true;
 135     if( !literal->containsNonAsciiOrNull())
 136         suitableString = true;
 137     return true;
 138     }
 139
 140 static Plugin::Registration< RtlConstAsciiMacro > X( "rtlconstasciimacro" );
 141
 142 } // namespace
 143
 144 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */