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pswalk.c revision 1.1.1.12 
      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