linux_old1/drivers/acpi/parser/pswalk.c

107 lines
3.4 KiB
C

/******************************************************************************
*
* Module Name: pswalk - Parser routines to walk parsed op tree(s)
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2006, R. Byron Moore
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*/
#include <acpi/acpi.h>
#include <acpi/acparser.h>
#define _COMPONENT ACPI_PARSER
ACPI_MODULE_NAME("pswalk")
/*******************************************************************************
*
* FUNCTION: acpi_ps_delete_parse_tree
*
* PARAMETERS: subtree_root - Root of tree (or subtree) to delete
*
* RETURN: None
*
* DESCRIPTION: Delete a portion of or an entire parse tree.
*
******************************************************************************/
void acpi_ps_delete_parse_tree(union acpi_parse_object *subtree_root)
{
union acpi_parse_object *op = subtree_root;
union acpi_parse_object *next = NULL;
union acpi_parse_object *parent = NULL;
ACPI_FUNCTION_TRACE_PTR("ps_delete_parse_tree", subtree_root);
/* Visit all nodes in the subtree */
while (op) {
/* Check if we are not ascending */
if (op != parent) {
/* Look for an argument or child of the current op */
next = acpi_ps_get_arg(op, 0);
if (next) {
/* Still going downward in tree (Op is not completed yet) */
op = next;
continue;
}
}
/* No more children, this Op is complete. */
next = op->common.next;
parent = op->common.parent;
acpi_ps_free_op(op);
/* If we are back to the starting point, the walk is complete. */
if (op == subtree_root) {
return_VOID;
}
if (next) {
op = next;
} else {
op = parent;
}
}
return_VOID;
}