xref: /reactos/drivers/bus/acpi/acpica/parser/pswalk.c (revision 9d33a205)
1 /******************************************************************************
2  *
3  * Module Name: pswalk - Parser routines to walk parsed op tree(s)
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2021, 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 MERCHANTABILITY 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 #include "amlcode.h"
65 
66 void
67 AcpiPsDeleteParseTree (
68     ACPI_PARSE_OBJECT       *SubtreeRoot)
69 {
70     ACPI_PARSE_OBJECT       *Op = SubtreeRoot;
71     ACPI_PARSE_OBJECT       *Next = NULL;
72     ACPI_PARSE_OBJECT       *Parent = NULL;
73     UINT32                  Level = 0;
74 
75 
76     ACPI_FUNCTION_TRACE_PTR (PsDeleteParseTree, SubtreeRoot);
77 
78     ACPI_DEBUG_PRINT ((ACPI_DB_PARSE_TREES,
79         " root %p\n", SubtreeRoot));
80 
81     /* Visit all nodes in the subtree */
82 
83     while (Op)
84     {
85         if (Op != Parent)
86         {
87             /* This is the descending case */
88 
89             if (ACPI_IS_DEBUG_ENABLED (ACPI_LV_PARSE_TREES, _COMPONENT))
90             {
91                 /* This debug option will print the entire parse tree */
92 
93                 AcpiOsPrintf ("        %*.s%s %p", (Level * 4), " ",
94                     AcpiPsGetOpcodeName (Op->Common.AmlOpcode), Op);
95 
96                 if (Op->Named.AmlOpcode == AML_INT_NAMEPATH_OP)
97                 {
98                     AcpiOsPrintf ("    %4.4s", Op->Common.Value.String);
99                 }
100                 if (Op->Named.AmlOpcode == AML_STRING_OP)
101                 {
102                     AcpiOsPrintf ("    %s", Op->Common.Value.String);
103                 }
104                 AcpiOsPrintf ("\n");
105             }
106 
107             /* Look for an argument or child of the current op */
108 
109             Next = AcpiPsGetArg (Op, 0);
110             if (Next)
111             {
112                 /* Still going downward in tree (Op is not completed yet) */
113 
114                 Op = Next;
115                 Level++;
116                 continue;
117             }
118         }
119 
120         /* No more children, this Op is complete. */
121 
122         Next = Op->Common.Next;
123         Parent = Op->Common.Parent;
124 
125         AcpiPsFreeOp (Op);
126 
127         /* If we are back to the starting point, the walk is complete. */
128 
129         if (Op == SubtreeRoot)
130         {
131             return_VOID;
132         }
133 
134         if (Next)
135         {
136             Op = Next;
137         }
138         else
139         {
140             Level--;
141             Op = Parent;
142         }
143     }
144 
145     return_VOID;
146 }
147