the begginning

utils/funcexp/func_reverse.cpp

@@ -0,0 +1,87 @@
+/* Copyright (C) 2014 InfiniDB, Inc.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; version 2 of
+   the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA. */
+
+/****************************************************************************
+* $Id: func_reverse.cpp 2477 2011-04-01 16:07:35Z rdempsey $
+*
+*
+****************************************************************************/
+
+#include <string>
+using namespace std;
+
+#include "functor_str.h"
+#include "functioncolumn.h"
+using namespace execplan;
+
+#include "rowgroup.h"
+using namespace rowgroup;
+
+#include "joblisttypes.h"
+using namespace joblist;
+
+#define STRCOLL_ENH__
+
+namespace
+{
+
+void reverse( char *start, char *end )
+{
+    while( start < end )
+    {
+        char c = *start;
+        *start++ = *end;
+        *end-- = c;
+    }
+}
+
+char *reverse_char( char *start )
+{
+    char *end = start;
+    while( (end[1] & 0xC0) == 0x80 ) end++;
+    reverse( start, end );
+    return( end+1 );
+}
+}
+
+namespace funcexp
+{
+
+CalpontSystemCatalog::ColType Func_reverse::operationType(FunctionParm& fp, CalpontSystemCatalog::ColType& resultType)
+{
+	// operation type is not used by this functor
+	return fp[0]->data()->resultType();
+}
+
+std::string Func_reverse::getStrVal(rowgroup::Row& row,
+						FunctionParm& fp,
+						bool& isNull,
+						execplan::CalpontSystemCatalog::ColType&)
+{
+	string str = stringValue(fp[0], row, isNull);
+
+    char *end = (char*) str.c_str();
+    while( *end ) end = reverse_char( end );
+    reverse( (char*) str.c_str(), end-1 );
+
+	return str;
+}
+
+
+} // namespace funcexp
+// vim:ts=4 sw=4:
+