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
  29 #define _COMPONENT          ACPI_DISPATCHER
  30          MODULE_NAME         ("dswscope")
  31
  32
  33 #define STACK_POP(head) head
  34
  35
  36 /****************************************************************************
  37  *
  38  * FUNCTION:    Acpi_ds_scope_stack_clear
  39  *
  40  * PARAMETERS:  None
  41  *
  42  * DESCRIPTION: Pop (and free) everything on the scope stack except the
  43  *              root scope object (which remains at the stack top.)
  44  *
  45  ***************************************************************************/
  46
  47 void
  48 acpi_ds_scope_stack_clear (
  49         ACPI_WALK_STATE         *walk_state)
  50 {
  51         ACPI_GENERIC_STATE      *scope_info;
  52
  53
  54         while (walk_state->scope_info) {
  55                 /* Pop a scope off the stack */
  56
  57                 scope_info = walk_state->scope_info;
  58                 walk_state->scope_info = scope_info->scope.next;
  59
  60                 acpi_cm_delete_generic_state (scope_info);
  61         }
  62 }
  63
  64
  65 /****************************************************************************
  66  *
  67  * FUNCTION:    Acpi_ds_scope_stack_push
  68  *
  69  * PARAMETERS:  *Node,              - Name to be made current
  70  *              Type,               - Type of frame being pushed
  71  *
  72  * DESCRIPTION: Push the current scope on the scope stack, and make the
  73  *              passed Node current.
  74  *
  75  ***************************************************************************/
  76
  77 ACPI_STATUS
  78 acpi_ds_scope_stack_push (
  79         ACPI_NAMESPACE_NODE     *node,
  80         OBJECT_TYPE_INTERNAL    type,
  81         ACPI_WALK_STATE         *walk_state)
  82 {
  83         ACPI_GENERIC_STATE      *scope_info;
  84
  85
  86         if (!node) {
  87                 /*  invalid scope   */
  88
  89                 REPORT_ERROR (("Ds_scope_stack_push: null scope passed\n"));
  90                 return (AE_BAD_PARAMETER);
  91         }
  92
  93         /* Make sure object type is valid */
  94
  95         if (!acpi_aml_validate_object_type (type)) {
  96                 REPORT_WARNING (("Ds_scope_stack_push: type code out of range\n"));
  97         }
  98
  99
 100         /* Allocate a new scope object */
 101
 102         scope_info = acpi_cm_create_generic_state ();
 103         if (!scope_info) {
 104                 return (AE_NO_MEMORY);
 105         }
 106
 107         /* Init new scope object */
 108
 109         scope_info->scope.node = node;
 110         scope_info->common.value = (u16) type;
 111
 112         /* Push new scope object onto stack */
 113
 114         acpi_cm_push_generic_state (&walk_state->scope_info, scope_info);
 115
 116         return (AE_OK);
 117 }
 118
 119
 120 /****************************************************************************
 121  *
 122  * FUNCTION:    Acpi_ds_scope_stack_pop
 123  *
 124  * PARAMETERS:  Type                - The type of frame to be found
 125  *
 126  * DESCRIPTION: Pop the scope stack until a frame of the requested type
 127  *              is found.
 128  *
 129  * RETURN:      Count of frames popped.  If no frame of the requested type
 130  *              was found, the count is returned as a negative number and
 131  *              the scope stack is emptied (which sets the current scope
 132  *              to the root).  If the scope stack was empty at entry, the
 133  *              function is a no-op and returns 0.
 134  *
 135  ***************************************************************************/
 136
 137 ACPI_STATUS
 138 acpi_ds_scope_stack_pop (
 139         ACPI_WALK_STATE         *walk_state)
 140 {
 141         ACPI_GENERIC_STATE      *scope_info;
 142
 143
 144         /*
 145          * Pop scope info object off the stack.
 146          */
 147
 148         scope_info = acpi_cm_pop_generic_state (&walk_state->scope_info);
 149         if (!scope_info) {
 150                 return (AE_STACK_UNDERFLOW);
 151         }
 152
 153         acpi_cm_delete_generic_state (scope_info);
 154
 155         return (AE_OK);
 156 }
 157
 158