reactos/drivers/bus/acpi/dispatcher/dswscope.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dswscope - Scope stack manipulation
   4  *              $Revision: 1.1 $
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  *  Copyright (C) 2000, 2001 R. Byron Moore
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or
  14  *  (at your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *  GNU General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License
  22  *  along with this program; if not, write to the Free Software
  23  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  24  */
  25
  26
  27 #include "acpi.h"
  28 #include "acinterp.h"
  29 #include "acdispat.h"
  30
  31
  32 #define _COMPONENT          ACPI_DISPATCHER
  33          MODULE_NAME         ("dswscope")
  34
  35
  36 #define STACK_POP(head) head
  37
  38
  39 /****************************************************************************
  40  *
  41  * FUNCTION:    Acpi_ds_scope_stack_clear
  42  *
  43  * PARAMETERS:  None
  44  *
  45  * DESCRIPTION: Pop (and free) everything on the scope stack except the
  46  *              root scope object (which remains at the stack top.)
  47  *
  48  ***************************************************************************/
  49
  50 void
  51 acpi_ds_scope_stack_clear (
  52         ACPI_WALK_STATE         *walk_state)
  53 {
  54         ACPI_GENERIC_STATE      *scope_info;
  55
  56
  57         while (walk_state->scope_info) {
  58                 /* Pop a scope off the stack */
  59
  60                 scope_info = walk_state->scope_info;
  61                 walk_state->scope_info = scope_info->scope.next;
  62
  63                 acpi_cm_delete_generic_state (scope_info);
  64         }
  65 }
  66
  67
  68 /****************************************************************************
  69  *
  70  * FUNCTION:    Acpi_ds_scope_stack_push
  71  *
  72  * PARAMETERS:  *Node,              - Name to be made current
  73  *              Type,               - Type of frame being pushed
  74  *
  75  * DESCRIPTION: Push the current scope on the scope stack, and make the
  76  *              passed Node current.
  77  *
  78  ***************************************************************************/
  79
  80 ACPI_STATUS
  81 acpi_ds_scope_stack_push (
  82         ACPI_NAMESPACE_NODE     *node,
  83         OBJECT_TYPE_INTERNAL    type,
  84         ACPI_WALK_STATE         *walk_state)
  85 {
  86         ACPI_GENERIC_STATE      *scope_info;
  87
  88
  89         if (!node) {
  90                 /*  invalid scope   */
  91
  92                 REPORT_ERROR (("Ds_scope_stack_push: null scope passed\n"));
  93                 return (AE_BAD_PARAMETER);
  94         }
  95
  96         /* Make sure object type is valid */
  97
  98         if (!acpi_aml_validate_object_type (type)) {
  99                 REPORT_WARNING (("Ds_scope_stack_push: type code out of range\n"));
 100         }
 101
 102
 103         /* Allocate a new scope object */
 104
 105         scope_info = acpi_cm_create_generic_state ();
 106         if (!scope_info) {
 107                 return (AE_NO_MEMORY);
 108         }
 109
 110         /* Init new scope object */
 111
 112         scope_info->scope.node = node;
 113         scope_info->common.value = (u16) type;
 114
 115         /* Push new scope object onto stack */
 116
 117         acpi_cm_push_generic_state (&walk_state->scope_info, scope_info);
 118
 119         return (AE_OK);
 120 }
 121
 122
 123 /****************************************************************************
 124  *
 125  * FUNCTION:    Acpi_ds_scope_stack_pop
 126  *
 127  * PARAMETERS:  Type                - The type of frame to be found
 128  *
 129  * DESCRIPTION: Pop the scope stack until a frame of the requested type
 130  *              is found.
 131  *
 132  * RETURN:      Count of frames popped.  If no frame of the requested type
 133  *              was found, the count is returned as a negative number and
 134  *              the scope stack is emptied (which sets the current scope
 135  *              to the root).  If the scope stack was empty at entry, the
 136  *              function is a no-op and returns 0.
 137  *
 138  ***************************************************************************/
 139
 140 ACPI_STATUS
 141 acpi_ds_scope_stack_pop (
 142         ACPI_WALK_STATE         *walk_state)
 143 {
 144         ACPI_GENERIC_STATE      *scope_info;
 145
 146
 147         /*
 148          * Pop scope info object off the stack.
 149          */
 150
 151         scope_info = acpi_cm_pop_generic_state (&walk_state->scope_info);
 152         if (!scope_info) {
 153                 return (AE_STACK_UNDERFLOW);
 154         }
 155
 156         acpi_cm_delete_generic_state (scope_info);
 157
 158         return (AE_OK);
 159 }
 160
 161