$include (..\lib\compStch.ext)

/*
 *============================================================================
 *  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
 *
 *  Permission to use for any purpose, modify, copy, and make enhancements
 *  and derivative works of the software is granted if attribution is given to
 *  R.M. Gillmore, dba the ACME Software Deli, as the author
 *
 *  While the ACME Software Deli does not work for money, there is nonetheless
 *  a significant amount of work involved.  The ACME Software Deli maintains the
 *  rights to all code written, though it may be used and distributed as long as
 *  the following conditions are maintained.
 *
 *  1.  The copyright statement at the top of each code block is maintained in
 *      your distribution.
 *  2.  You do not identify yourself as the ACME Software Deli
 *  3.  Any changes made to the software are sent to the ACME Software Deli
 *============================================================================
 */

changeFileExtensionModule:
do;
$if not noID
declare IDString	(*) byte data
	( '@(#)changExt.p86  $Author: rmgillmore $ $Date:: 2025-05-04 19:35:39#$:', 0 );
$endif

$include (..\lib\comnDefs.ext)
$set (chgExtensionImplementation)
$include (..\lib\changExt.ext)
$include (..\lib\string.ext)
$include (..\lib\ptrMath.ext)

changeExtension:
procedure ( fileNameString, newExtension ) public;
	declare	fileNameString				pointer,
			newExtension				pointer;

	declare	dotPtr						pointer,
			dot				based	dotPtr	(*)	char,
			slashPtr					pointer;

	declare	extensionDelimiter		(*)	char data ( '.', 0 );

	/*
	 *	Look for the last '.' character in the string.  If
	 *	there is no '.' character, or if it appears BEFORE the
	 *	last path delimiter, we need to append one
	 */

	dotPtr = strrchr( fileNameString, extensionDelimiter( 0 ) );
	slashPtr = strrchr( fileNameString, PATH_DELIM );
	if ( ( dotPtr = NULL ) or
		( ptdw( normalizePtr( slashPtr ) ) > ptdw( normalizePtr( dotPtr ) ) ) ) then
	do;
		call strcat( fileNameString, @extensionDelimiter );
		dotPtr = strrchr( fileNameString, extensionDelimiter( 0 ) );
	end;

	/*
	 *	The '.' character DEFINITELY exists now, point to the
	 *	first character past it, and move the new extension
	 *	into that position.  It should be noted that the NUL
	 *	character is copied also
	 */

	call strcpy( @dot( 1 ), newExtension );
end changeExtension;

end changeFileExtensionModule;