stack.cpp

< Game Script Mastery>> source code

/*

    Project.

        XSC - The XtremeScript Compiler Version 0.8

    Abstract.

        Stack implementation

    Date Created.

        9.3.2002

    Author.

        Alex Varanese

*/

// ---- Include Files -------------------------------------------------------------------------

    #include "stack.h"

// ---- Functions -----------------------------------------------------------------------------

    /******************************************************************************************
    *
    *   InitStack ()
    *
    *   Initializes a stack.
    */

    void InitStack ( Stack * pStack )
    {
        // Initialize the stack's internal list

        InitLinkedList ( & pStack->ElmntList );
    }

    /******************************************************************************************
    *
    *   FreeStack ()
    *
    *   Frees a stack.
    */

    void FreeStack ( Stack * pStack )
    {
        // Free the stack's internal list

        FreeLinkedList ( & pStack->ElmntList );
    }

    /******************************************************************************************
    *
    *   IsStackEmpty ()
    *
    *   Returns TRUE if the specified stack is empty, FALSE otherwise.
    */

    int IsStackEmpty ( Stack * pStack )
    {
        if ( pStack->ElmntList.iNodeCount > 0 )
            return FALSE;
        else
            return TRUE;
    }

    /******************************************************************************************
    *
    *   Push ()
    *
    *   Pushes an element onto a stack.
    */

    void Push ( Stack * pStack, void * pData )
    {
        // Add a node to the end of the stack's internal list

        AddNode ( & pStack->ElmntList, pData );
    }

    /******************************************************************************************
    *
    *   Pop ()
    *
    *   Pops an element off the top of a stack.
    */

    void Pop ( Stack * pStack )
    {
        // Free the tail node of the list and it's data

        DelNode ( & pStack->ElmntList, pStack->ElmntList.pTail );
    }

    /******************************************************************************************
    *
    *   Peek ()
    *
    *   Returns the element at the top of a stack.
    */

    void * Peek ( Stack * pStack )
    {
        // Return the data at the tail node of the list

        return pStack->ElmntList.pTail->pData;
    }