1 /****************************************************************************** 2 * 3 * Module Name: pswalk - Parser routines to walk parsed op tree(s) 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2015, Intel Corp. 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions, and the following disclaimer, 16 * without modification. 17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 18 * substantially similar to the "NO WARRANTY" disclaimer below 19 * ("Disclaimer") and any redistribution must be conditioned upon 20 * including a substantially similar Disclaimer requirement for further 21 * binary redistribution. 22 * 3. Neither the names of the above-listed copyright holders nor the names 23 * of any contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * Alternatively, this software may be distributed under the terms of the 27 * GNU General Public License ("GPL") version 2 as published by the Free 28 * Software Foundation. 29 * 30 * NO WARRANTY 31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 41 * POSSIBILITY OF SUCH DAMAGES. 42 */ 43 44 #include <acpi/acpi.h> 45 #include "accommon.h" 46 #include "acparser.h" 47 48 #define _COMPONENT ACPI_PARSER 49 ACPI_MODULE_NAME("pswalk") 50 51 /******************************************************************************* 52 * 53 * FUNCTION: acpi_ps_delete_parse_tree 54 * 55 * PARAMETERS: subtree_root - Root of tree (or subtree) to delete 56 * 57 * RETURN: None 58 * 59 * DESCRIPTION: Delete a portion of or an entire parse tree. 60 * 61 ******************************************************************************/ 62 void acpi_ps_delete_parse_tree(union acpi_parse_object *subtree_root) 63 { 64 union acpi_parse_object *op = subtree_root; 65 union acpi_parse_object *next = NULL; 66 union acpi_parse_object *parent = NULL; 67 68 ACPI_FUNCTION_TRACE_PTR(ps_delete_parse_tree, subtree_root); 69 70 /* Visit all nodes in the subtree */ 71 72 while (op) { 73 74 /* Check if we are not ascending */ 75 76 if (op != parent) { 77 78 /* Look for an argument or child of the current op */ 79 80 next = acpi_ps_get_arg(op, 0); 81 if (next) { 82 83 /* Still going downward in tree (Op is not completed yet) */ 84 85 op = next; 86 continue; 87 } 88 } 89 90 /* No more children, this Op is complete. */ 91 92 next = op->common.next; 93 parent = op->common.parent; 94 95 acpi_ps_free_op(op); 96 97 /* If we are back to the starting point, the walk is complete. */ 98 99 if (op == subtree_root) { 100 return_VOID; 101 } 102 if (next) { 103 op = next; 104 } else { 105 op = parent; 106 } 107 } 108 109 return_VOID; 110 } 111