text: /******************************************************************************
   *
   * Module Name: dswscope - Scope stack manipulation
   *
   *****************************************************************************/
  
  /*
   * Copyright (C) 2000 - 2010, Intel Corp.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions, and the following disclaimer,
   *    without modification.
   * 2. Redistributions in binary form must reproduce at minimum a disclaimer
   *    substantially similar to the "NO WARRANTY" disclaimer below
   *    ("Disclaimer") and any redistribution must be conditioned upon
   *    including a substantially similar Disclaimer requirement for further
   *    binary redistribution.
   * 3. Neither the names of the above-listed copyright holders nor the names
   *    of any contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * Alternatively, this software may be distributed under the terms of the
   * GNU General Public License ("GPL") version 2 as published by the Free
   * Software Foundation.
   *
   * NO WARRANTY
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGES.
   */
  
  #include <acpi/acpi.h>
  #include "accommon.h"
  #include "acdispat.h"
  
  #define _COMPONENT          ACPI_DISPATCHER
  ACPI_MODULE_NAME("dswscope")
  
  /****************************************************************************
   *
   * FUNCTION:    acpi_ds_scope_stack_clear
   *
   * PARAMETERS:  walk_state      - Current state
   *
   * RETURN:      None
   *
   * DESCRIPTION: Pop (and free) everything on the scope stack except the
   *              root scope object (which remains at the stack top.)
   *
   ***************************************************************************/
  void acpi_ds_scope_stack_clear(struct acpi_walk_state *walk_state)
  {
  	union acpi_generic_state *scope_info;
  
  	ACPI_FUNCTION_NAME(ds_scope_stack_clear);
  
  	while (walk_state->scope_info) {
  
  		/* Pop a scope off the stack */
  
  		scope_info = walk_state->scope_info;
  		walk_state->scope_info = scope_info->scope.next;
  
  		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  				  "Popped object type (%s)\n",
  				  acpi_ut_get_type_name(scope_info->common.
  							value)));
  		acpi_ut_delete_generic_state(scope_info);
  	}
  }
  
  /****************************************************************************
   *
   * FUNCTION:    acpi_ds_scope_stack_push
   *
   * PARAMETERS:  Node            - Name to be made current
   *              Type            - Type of frame being pushed
   *              walk_state      - Current state
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Push the current scope on the scope stack, and make the
   *              passed Node current.
   *
   ***************************************************************************/
  
  acpi_status
  acpi_ds_scope_stack_push(struct acpi_namespace_node *node,
  			 acpi_object_type type,
  			 struct acpi_walk_state *walk_state)
  {
  	union acpi_generic_state *scope_info;
  	union acpi_generic_state *old_scope_info;
  
  	ACPI_FUNCTION_TRACE(ds_scope_stack_push);
  
  	if (!node) {
  
  		/* Invalid scope   */
  
  		ACPI_ERROR((AE_INFO, "Null scope parameter"));
  		return_ACPI_STATUS(AE_BAD_PARAMETER);
  	}
  
  	/* Make sure object type is valid */
  
  	if (!acpi_ut_valid_object_type(type)) {
  		ACPI_WARNING((AE_INFO, "Invalid object type: 0x%X", type));
  	}
  
  	/* Allocate a new scope object */
  
  	scope_info = acpi_ut_create_generic_state();
  	if (!scope_info) {
  		return_ACPI_STATUS(AE_NO_MEMORY);
  	}
  
  	/* Init new scope object */
  
  	scope_info->common.descriptor_type = ACPI_DESC_TYPE_STATE_WSCOPE;
  	scope_info->scope.node = node;
  	scope_info->common.value = (u16) type;
  
  	walk_state->scope_depth++;
  
  	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  			  "[%.2d] Pushed scope ",
  			  (u32) walk_state->scope_depth));
  
  	old_scope_info = walk_state->scope_info;
  	if (old_scope_info) {
  		ACPI_DEBUG_PRINT_RAW((ACPI_DB_EXEC,
  				      "[%4.4s] (%s)",
  				      acpi_ut_get_node_name(old_scope_info->
  							    scope.node),
  				      acpi_ut_get_type_name(old_scope_info->
  							    common.value)));
  	} else {
  		ACPI_DEBUG_PRINT_RAW((ACPI_DB_EXEC, "[\\___] (%s)", "ROOT"));
  	}
  
  	ACPI_DEBUG_PRINT_RAW((ACPI_DB_EXEC,
  			      ", New scope -> [%4.4s] (%s)\n",
  			      acpi_ut_get_node_name(scope_info->scope.node),
  			      acpi_ut_get_type_name(scope_info->common.value)));
  
  	/* Push new scope object onto stack */
  
  	acpi_ut_push_generic_state(&walk_state->scope_info, scope_info);
  	return_ACPI_STATUS(AE_OK);
  }
  
  /****************************************************************************
   *
   * FUNCTION:    acpi_ds_scope_stack_pop
   *
   * PARAMETERS:  walk_state      - Current state
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Pop the scope stack once.
   *
   ***************************************************************************/
  
  acpi_status acpi_ds_scope_stack_pop(struct acpi_walk_state *walk_state)
  {
  	union acpi_generic_state *scope_info;
  	union acpi_generic_state *new_scope_info;
  
  	ACPI_FUNCTION_TRACE(ds_scope_stack_pop);
  
  	/*
  	 * Pop scope info object off the stack.
  	 */
  	scope_info = acpi_ut_pop_generic_state(&walk_state->scope_info);
  	if (!scope_info) {
  		return_ACPI_STATUS(AE_STACK_UNDERFLOW);
  	}
  
  	walk_state->scope_depth--;
  
  	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  			  "[%.2d] Popped scope [%4.4s] (%s), New scope -> ",
  			  (u32) walk_state->scope_depth,
  			  acpi_ut_get_node_name(scope_info->scope.node),
  			  acpi_ut_get_type_name(scope_info->common.value)));
  
  	new_scope_info = walk_state->scope_info;
  	if (new_scope_info) {
  		ACPI_DEBUG_PRINT_RAW((ACPI_DB_EXEC,
  				      "[%4.4s] (%s)\n",
  				      acpi_ut_get_node_name(new_scope_info->
  							    scope.node),
  				      acpi_ut_get_type_name(new_scope_info->
  							    common.value)));
  	} else {
  		ACPI_DEBUG_PRINT_RAW((ACPI_DB_EXEC, "[\\___] (ROOT)\n"));
  	}
  
  	acpi_ut_delete_generic_state(scope_info);
  	return_ACPI_STATUS(AE_OK);
  }
  