asltree.c

acpi tools for linux include acpiexec and acpixtract

ACPI_PARSE_OBJECT *
TrLinkPeerNode (
    ACPI_PARSE_OBJECT       *Op1,
    ACPI_PARSE_OBJECT       *Op2)
{
    ACPI_PARSE_OBJECT       *Next;


    DbgPrint (ASL_PARSE_OUTPUT,
        "\nLinkPeerNode: 1=%p (%s), 2=%p (%s)\n\n",
        Op1, Op1 ? UtGetOpName(Op1->Asl.ParseOpcode) : NULL,
        Op2, Op2 ? UtGetOpName(Op2->Asl.ParseOpcode) : NULL);


    if ((!Op1) && (!Op2))
    {
        DbgPrint (ASL_PARSE_OUTPUT, "\nTwo Null nodes!\n");
        return Op1;
    }

    /* If one of the nodes is null, just return the non-null node */

    if (!Op2)
    {
        return Op1;
    }

    if (!Op1)
    {
        return Op2;
    }

    if (Op1 == Op2)
    {
        DbgPrint (ASL_DEBUG_OUTPUT,
            "\n\n************* Internal error, linking node to itself %p\n\n\n",
            Op1);
        AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op1,
            "Linking node to itself");
        return Op1;
    }

    Op1->Asl.Parent = Op2->Asl.Parent;

    /*
     * Op 1 may already have a peer list (such as an IF/ELSE pair),
     * so we must walk to the end of the list and attach the new
     * peer at the end
     */
    Next = Op1;
    while (Next->Asl.Next)
    {
        Next = Next->Asl.Next;
    }

    Next->Asl.Next = Op2;
    return Op1;
}


/*******************************************************************************
 *
 * FUNCTION:    TrLinkPeerNodes
 *
 * PARAMETERS:  NumPeers            - The number of nodes in the list to follow
 *              ...                 - A list of nodes to link together as peers
 *
 * RETURN:      The first node in the list (head of the peer list)
 *
 * DESCRIPTION: Link together an arbitrary number of peer nodes.
 *
 ******************************************************************************/

ACPI_PARSE_OBJECT *
TrLinkPeerNodes (
    UINT32                  NumPeers,
    ...)
{
    ACPI_PARSE_OBJECT       *This;
    ACPI_PARSE_OBJECT       *Next;
    va_list                 ap;
    UINT32                  i;
    ACPI_PARSE_OBJECT       *Start;


    DbgPrint (ASL_PARSE_OUTPUT,
        "\nLinkPeerNodes: (%d) ", NumPeers);

    va_start (ap, NumPeers);
    This = va_arg (ap, ACPI_PARSE_OBJECT *);
    Start = This;

    /*
     * Link all peers
     */
    for (i = 0; i < (NumPeers -1); i++)
    {
        DbgPrint (ASL_PARSE_OUTPUT, "%d=%p ", (i+1), This);

        while (This->Asl.Next)
        {
            This = This->Asl.Next;
        }

        /* Get another peer node */

        Next = va_arg (ap, ACPI_PARSE_OBJECT *);
        if (!Next)
        {
            Next = TrAllocateNode (PARSEOP_DEFAULT_ARG);
        }

        /* link new node to the current node */

        This->Asl.Next = Next;
        This = Next;
    }
    va_end (ap);

    DbgPrint (ASL_PARSE_OUTPUT,"\n\n");
    return (Start);
}


/*******************************************************************************
 *
 * FUNCTION:    TrLinkChildNode
 *
 * PARAMETERS:  Op1           - Parent node
 *              Op2           - Op to become a child
 *
 * RETURN:      The parent node
 *
 * DESCRIPTION: Link two nodes together as a parent and child
 *
 ******************************************************************************/

ACPI_PARSE_OBJECT *
TrLinkChildNode (
    ACPI_PARSE_OBJECT       *Op1,
    ACPI_PARSE_OBJECT       *Op2)
{
    ACPI_PARSE_OBJECT       *Next;


    DbgPrint (ASL_PARSE_OUTPUT,
        "\nLinkChildNode: Parent=%p (%s), Child=%p (%s)\n\n",
        Op1, Op1 ? UtGetOpName(Op1->Asl.ParseOpcode): NULL,
        Op2, Op2 ? UtGetOpName(Op2->Asl.ParseOpcode): NULL);

    if (!Op1 || !Op2)
    {
        return Op1;
    }

    Op1->Asl.Child = Op2;

    /* Set the child and all peers of the child to point to the parent */

    Next = Op2;
    while (Next)
    {
        Next->Asl.Parent = Op1;
        Next = Next->Asl.Next;
    }

    return Op1;
}


/*******************************************************************************
 *
 * FUNCTION:    TrWalkParseTree
 *
 * PARAMETERS:  Visitation              - Type of walk
 *              DescendingCallback      - Called during tree descent
 *              AscendingCallback       - Called during tree ascent
 *              Context                 - To be passed to the callbacks
 *
 * RETURN:      Status from callback(s)
 *
 * DESCRIPTION: Walk the entire parse tree.
 *
 ******************************************************************************/

ACPI_STATUS
TrWalkParseTree (
    ACPI_PARSE_OBJECT       *Op,
    UINT32                  Visitation,
    ASL_WALK_CALLBACK       DescendingCallback,
    ASL_WALK_CALLBACK       AscendingCallback,
    void                    *Context)
{
    UINT32                  Level;
    BOOLEAN                 NodePreviouslyVisited;
    ACPI_PARSE_OBJECT       *StartOp = Op;
    ACPI_STATUS             Status;


    if (!RootNode)
    {
        return (AE_OK);
    }

    Level = 0;
    NodePreviouslyVisited = FALSE;

    switch (Visitation)
    {
    case ASL_WALK_VISIT_DOWNWARD:

        while (Op)
        {
            if (!NodePreviouslyVisited)
            {
                /* Let the callback process the node. */

                Status = DescendingCallback (Op, Level, Context);
                if (ACPI_SUCCESS (Status))
                {
                    /* Visit children first, once */

                    if (Op->Asl.Child)
                    {
                        Level++;
                        Op = Op->Asl.Child;
                        continue;
                    }
                }
                else if (Status != AE_CTRL_DEPTH)
                {
                    /* Exit immediately on any error */

                    return (Status);
                }
            }

            /* Terminate walk at start op */

            if (Op == StartOp)
            {
                break;
            }

            /* No more children, visit peers */

            if (Op->Asl.Next)
            {
                Op = Op->Asl.Next;
                NodePreviouslyVisited = FALSE;
            }
            else
            {
                /* No children or peers, re-visit parent */

                if (Level != 0 )
                {
                    Level--;
                }
                Op = Op->Asl.Parent;
                NodePreviouslyVisited = TRUE;
            }
        }
        break;


    case ASL_WALK_VISIT_UPWARD:

        while (Op)
        {
            /* Visit leaf node (no children) or parent node on return trip */

            if ((!Op->Asl.Child) ||
                (NodePreviouslyVisited))
            {
                /* Let the callback process the node. */

                Status = AscendingCallback (Op, Level, Context);
                if (ACPI_FAILURE (Status))
                {
                    return (Status);
                }
            }
            else
            {
                /* Visit children first, once */

                Level++;
                Op = Op->Asl.Child;
                continue;
            }

            /* Terminate walk at start op */

            if (Op == StartOp)
            {
                break;
            }

            /* No more children, visit peers */

            if (Op->Asl.Next)
            {
                Op = Op->Asl.Next;
                NodePreviouslyVisited = FALSE;
            }
            else
            {
                /* No children or peers, re-visit parent */

                if (Level != 0 )
                {
                    Level--;
                }
                Op = Op->Asl.Parent;
                NodePreviouslyVisited = TRUE;
            }
        }
        break;


     case ASL_WALK_VISIT_TWICE:

        while (Op)
        {
            if (NodePreviouslyVisited)
            {
                Status = AscendingCallback (Op, Level, Context);
                if (ACPI_FAILURE (Status))
                {
                    return (Status);
                }
            }
            else
            {
                /* Let the callback process the node. */

                Status = DescendingCallback (Op, Level, Context);
                if (ACPI_SUCCESS (Status))
                {
                    /* Visit children first, once */

                    if (Op->Asl.Child)
                    {
                        Level++;
                        Op = Op->Asl.Child;
                        continue;
                    }
                }
                else if (Status != AE_CTRL_DEPTH)
                {
                    /* Exit immediately on any error */

                    return (Status);
                }
            }

            /* Terminate walk at start op */

            if (Op == StartOp)
            {
                break;
            }

            /* No more children, visit peers */

            if (Op->Asl.Next)
            {
                Op = Op->Asl.Next;
                NodePreviouslyVisited = FALSE;
            }
            else
            {
                /* No children or peers, re-visit parent */

                if (Level != 0 )
                {
                    Level--;
                }
                Op = Op->Asl.Parent;
                NodePreviouslyVisited = TRUE;
            }
        }
        break;

    default:
        /* No other types supported */
        break;
    }

    /* If we get here, the walk completed with no errors */

    return (AE_OK);
}