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
AcpiPsDeleteParseTree(ACPI_PARSE_OBJECT * SubtreeRoot)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