dswstate.c

Linux内核源代码 为压缩文件 是<<Linux内核>>一书中的源代码

/******************************************************************************
 *
 * Module Name: dswstate - Dispatcher parse tree walk management routines
 *              $Revision: 36 $
 *
 *****************************************************************************/

/*
 *  Copyright (C) 2000 R. Byron Moore
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "acpi.h"
#include "amlcode.h"
#include "acparser.h"
#include "acdispat.h"
#include "acnamesp.h"
#include "acinterp.h"

#define _COMPONENT          DISPATCHER
	 MODULE_NAME         ("dswstate")


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_stack_clear
 *
 * PARAMETERS:  Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Reset this walk's result stack pointers to zero, thus setting
 *              the stack to zero.
 *
 ******************************************************************************/

ACPI_STATUS
xxx_acpi_ds_result_stack_clear (
	ACPI_WALK_STATE         *walk_state)
{
/*
	Walk_state->Num_results = 0;
	Walk_state->Current_result = 0;
*/
	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_insert
 *
 * PARAMETERS:  Object              - Object to push
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Push an object onto this walk's result stack
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_result_insert (
	void                    *object,
	u32                     index,
	ACPI_WALK_STATE         *walk_state)
{
	ACPI_GENERIC_STATE      *state;


	state = walk_state->results;
	if (!state) {
		return (AE_NOT_EXIST);
	}

	if (index >= OBJ_NUM_OPERANDS) {
		return (AE_BAD_PARAMETER);
	}

	if (!object) {
		return (AE_BAD_PARAMETER);
	}

	state->results.obj_desc [index] = object;
	state->results.num_results++;

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_remove
 *
 * PARAMETERS:  Object              - Where to return the popped object
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 *              other words, this is a FIFO.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_result_remove (
	ACPI_OPERAND_OBJECT     **object,
	u32                     index,
	ACPI_WALK_STATE         *walk_state)
{
	ACPI_GENERIC_STATE      *state;


	state = walk_state->results;
	if (!state) {
		return (AE_NOT_EXIST);
	}



	/* Check for a valid result object */

	if (!state->results.obj_desc [index]) {
		return (AE_AML_NO_OPERAND);
	}

	/* Remove the object */

	state->results.num_results--;

	*object = state->results.obj_desc [index];
	state->results.obj_desc [index] = NULL;

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_pop
 *
 * PARAMETERS:  Object              - Where to return the popped object
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 *              other words, this is a FIFO.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_result_pop (
	ACPI_OPERAND_OBJECT     **object,
	ACPI_WALK_STATE         *walk_state)
{
	u32                     index;
	ACPI_GENERIC_STATE      *state;


	state = walk_state->results;
	if (!state) {
		return (AE_OK);
	}


	if (!state->results.num_results) {
		return (AE_STACK_UNDERFLOW);
	}

	/* Remove top element */

	state->results.num_results--;

	for (index = OBJ_NUM_OPERANDS; index; index--) {
		/* Check for a valid result object */

		if (state->results.obj_desc [index -1]) {
			*object = state->results.obj_desc [index -1];
			state->results.obj_desc [index -1] = NULL;

			return (AE_OK);
		}
	}


	return (AE_STACK_UNDERFLOW);
}

/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_pop
 *
 * PARAMETERS:  Object              - Where to return the popped object
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 *              other words, this is a FIFO.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_result_pop_from_bottom (
	ACPI_OPERAND_OBJECT     **object,
	ACPI_WALK_STATE         *walk_state)
{
	u32                     index;
	ACPI_GENERIC_STATE      *state;


	state = walk_state->results;
	if (!state) {
		return (AE_NOT_EXIST);
	}


	if (!state->results.num_results) {
		return (AE_STACK_UNDERFLOW);
	}

	/* Remove Bottom element */

	*object = state->results.obj_desc [0];


	/* Push entire stack down one element */

	for (index = 0; index < state->results.num_results; index++) {
		state->results.obj_desc [index] = state->results.obj_desc [index + 1];
	}

	state->results.num_results--;

	/* Check for a valid result object */

	if (!*object) {
		return (AE_AML_NO_OPERAND);
	}


	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_pop
 *
 * PARAMETERS:  Object              - Where to return the popped object
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 *              other words, this is a FIFO.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_result_push (
	ACPI_OPERAND_OBJECT     *object,
	ACPI_WALK_STATE         *walk_state)
{
	ACPI_GENERIC_STATE      *state;


	state = walk_state->results;
	if (!state) {
		return (AE_OK);
	}

	if (state->results.num_results == OBJ_NUM_OPERANDS) {
		return (AE_STACK_OVERFLOW);
	}

	if (!object) {
		return (AE_BAD_PARAMETER);
	}


	state->results.obj_desc [state->results.num_results] = object;
	state->results.num_results++;

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_stack_push
 *
 * PARAMETERS:  Object              - Object to push
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION:
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_result_stack_push (
	ACPI_WALK_STATE         *walk_state)
{
	ACPI_GENERIC_STATE      *state;


	state = acpi_cm_create_generic_state ();
	if (!state) {
		return (AE_NO_MEMORY);
	}

	acpi_cm_push_generic_state (&walk_state->results, state);

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_result_stack_pop
 *
 * PARAMETERS:  Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION:
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_result_stack_pop (
	ACPI_WALK_STATE         *walk_state)
{
	ACPI_GENERIC_STATE      *state;


	/* Check for stack underflow */

	if (walk_state->results == NULL) {
		return (AE_AML_NO_OPERAND);
	}


	state = acpi_cm_pop_generic_state (&walk_state->results);

	acpi_cm_delete_generic_state (state);

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_obj_stack_delete_all
 *
 * PARAMETERS:  Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
 *              Should be used with great care, if at all!
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_obj_stack_delete_all (
	ACPI_WALK_STATE         *walk_state)
{
	u32                     i;


	/* The stack size is configurable, but fixed */

	for (i = 0; i < OBJ_NUM_OPERANDS; i++) {
		if (walk_state->operands[i]) {
			acpi_cm_remove_reference (walk_state->operands[i]);
			walk_state->operands[i] = NULL;
		}
	}

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_obj_stack_push
 *
 * PARAMETERS:  Object              - Object to push
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Push an object onto this walk's object/operand stack
 *
 ******************************************************************************/

ACPI_STATUS
acpi_ds_obj_stack_push (
	void                    *object,
	ACPI_WALK_STATE         *walk_state)
{


	/* Check for stack overflow */

	if (walk_state->num_operands >= OBJ_NUM_OPERANDS) {
		return (AE_STACK_OVERFLOW);
	}

	/* Put the object onto the stack */

	walk_state->operands [walk_state->num_operands] = object;
	walk_state->num_operands++;

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ds_obj_stack_pop_object
 *
 * PARAMETERS:  Pop_count           - Number of objects/entries to pop
 *              Walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 *              deleted by this routine.