1 /****************************************************************************** 2 * 3 * Module Name: pswalk - Parser routines to walk parsed op tree(s) 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2016, 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.h" 45 #include "accommon.h" 46 #include "acparser.h" 47 48 #define _COMPONENT ACPI_PARSER 49 ACPI_MODULE_NAME ("pswalk") 50 51 52 /******************************************************************************* 53 * 54 * FUNCTION: AcpiPsDeleteParseTree 55 * 56 * PARAMETERS: SubtreeRoot - Root of tree (or subtree) to delete 57 * 58 * RETURN: None 59 * 60 * DESCRIPTION: Delete a portion of or an entire parse tree. 61 * 62 ******************************************************************************/ 63 64 void 65 AcpiPsDeleteParseTree ( 66 ACPI_PARSE_OBJECT *SubtreeRoot) 67 { 68 ACPI_PARSE_OBJECT *Op = SubtreeRoot; 69 ACPI_PARSE_OBJECT *Next = NULL; 70 ACPI_PARSE_OBJECT *Parent = NULL; 71 72 73 ACPI_FUNCTION_TRACE_PTR (PsDeleteParseTree, SubtreeRoot); 74 75 76 /* Visit all nodes in the subtree */ 77 78 while (Op) 79 { 80 /* Check if we are not ascending */ 81 82 if (Op != Parent) 83 { 84 /* Look for an argument or child of the current op */ 85 86 Next = AcpiPsGetArg (Op, 0); 87 if (Next) 88 { 89 /* Still going downward in tree (Op is not completed yet) */ 90 91 Op = Next; 92 continue; 93 } 94 } 95 96 /* No more children, this Op is complete. */ 97 98 Next = Op->Common.Next; 99 Parent = Op->Common.Parent; 100 101 AcpiPsFreeOp (Op); 102 103 /* If we are back to the starting point, the walk is complete. */ 104 105 if (Op == SubtreeRoot) 106 { 107 return_VOID; 108 } 109 110 if (Next) 111 { 112 Op = Next; 113 } 114 else 115 { 116 Op = Parent; 117 } 118 } 119 120 return_VOID; 121 } 122