/*
    $Id: clonetagitems.c,v 1.3 1996/10/24 15:51:35 aros Exp $
    $Log: clonetagitems.c,v $
    Revision 1.3  1996/10/24 15:51:35  aros
    Use the official AROS macros over the __AROS versions.

    Revision 1.2  1996/10/23 14:08:28  aros
    Formatted

    Added parens to all assignments which are used truth expressions

    Revision 1.1  1996/10/22 04:45:59  aros
    Some more utility.library functions.

    Desc: CloneTagItems()
    Lang: english
*/
#include "utility_intern.h"

/*****************************************************************************

    NAME */
	#include <utility/tagitem.h>
	#include <clib/utility_protos.h>

	AROS_LH1(struct TagItem *, CloneTagItems,

/*  SYNOPSIS */
	AROS_LHA(struct TagItem *, tagList, A0),

/*  LOCATION */
	struct UtilityBase *, UtilityBase, 12, Utility)

/*  FUNCTION
	Duplicates a TagList

    INPUTS
	tagList     -	The TagList that you want to clone

    RESULT
	A TagList which contains a copy of the TagItems contained in the
	original list. The list is cloned so that calling FindTagItem()
	on a tag in the clone will return the same value as that in the
	original list (assuming the original has not been modified).

    NOTES
	If the original TagList is NULL, then no cloning will take place.

    EXAMPLE
	struct TagItem *tagList, *tagListClone;

	\* Set up the original taglist tagList *\

	tagListClone = CloneTagItems( tagList );

	\* Do what you want with your TagList here *\

	FreeTagItems( tagListClone );

    BUGS

    SEE ALSO
	<utility/tagitem.h>, AllocateTagItems(), FreeTagItems(),
	RefreshTagItemClones()

    INTERNALS

    HISTORY
	29-10-95    digulla automatically created from
			    utility_lib.fd and clib/utility_protos.h
	11-08-96    iaint   Implemented as AROS function.
	01-09-96    iaint   Updated the docs to give the same warnings
			    as the autodocs.
	05-09-96    iaint   Bit of optimisation (one variable :( )

*****************************************************************************/
{
    AROS_LIBFUNC_INIT

    struct TagItem *newList,
		   *ti;
    LONG numTags = 1;

    /* Make sure we actually have some valid input here... */
    if (!tagList)
	return NULL;

    /*
	We start the counter at 1 since this count will not include the
	TAG_DONE TagItem

	newList is used here to save a variable. We don't need to do
	anything to the value of newList afterwards, since AllocateTagitems()
	will take care of setting it to NULL if the allocation fails.
    */
    newList = tagList;
    while ((ti = NextTagItem (&newList)))
	numTags++;

    /*
	Then we shall allocate the TagList.
	If we can actually allocate a clone tag list, then we shall copy
	the tag values from one tag to another, the function
	"RefreshTagItemClones()" is used here to help re-use code.

	Of course we don't have to worry about the if statement, since
	the original is guaranteed to have not been changed since
	CloneTagItems() :)
    */

    if ((newList = AllocateTagItems (numTags)))
	RefreshTagItemClones (newList, tagList);

    /* newList == 0 when allocation failed - AllocateTagItems handles this*/
    return newList;

    AROS_LIBFUNC_EXIT
} /* CloneTagItems */