/******************************************************************************
 *
 * Module Name: dswscope - Scope stack manipulation
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2006, R. Byron Moore
 * 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 <acpi/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);
}