Re: Memory Leaks - Can you help me find them in ths snippet

* nmehring@gmail.com:


Using malloc for allocation and delete[] for deallocation is Undefined
Behavior.

Code below would be better expressed using ScopeGuard.

But in order not to bring in that library (disclaimer: code not touched
by compiler's hands):

   class Columns
   {
   private:
       std::vector<char*> myColumns;

       void dealloc()
       {
           for( size_t i = 0; i < myColumns.size(); ++i )
           {
               delete[] myColumns[i];
           }
       }

   public:
       Columns(): myColumns( ::lColumnCount )
       {
           try
           {
               for( int i = 0; i < lColumnCount; ++i )
               {
                   myColumns[i] = new char[SE_QUALIFIED_COLUMN_LEN];
                   strcpy( myColumns[i], ::CStringColumnsName[i] );
               }
           }
           catch( std::bad_alloc const& )
           {
               dealloc();
               throw;
           }
       }

       ~Columns() { dealloc(); }

       char** pFirst() { return &myColumns[0]; }
   };

   bool foo()
   {
       try
       {

           Columns columns;
           someApiFunc( columns.pFirst() );
           return true;
       }
       catch( ... )
       {
           return false;
       }
   }

foo() could be simpler if it signalled failure via exception rather than
via a bool result.

Cheers & hth.,

- Alf

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