cmobject.c

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 * RETURN:      None.
 *
 * DESCRIPTION: Initialize a static object.  Sets flags to disallow dynamic
 *              deletion of the object.
 *
 ****************************************************************************/

void
acpi_cm_init_static_object (
	ACPI_OPERAND_OBJECT     *obj_desc)
{


	if (!obj_desc) {
		return;
	}


	/*
	 * Clear the entire descriptor
	 */
	MEMSET ((void *) obj_desc, 0, sizeof (ACPI_OPERAND_OBJECT));


	/*
	 * Initialize the header fields
	 * 1) This is an ACPI_OPERAND_OBJECT  descriptor
	 * 2) The size is the full object (worst case)
	 * 3) The flags field indicates static allocation
	 * 4) Reference count starts at one (not really necessary since the
	 *    object can't be deleted, but keeps everything sane)
	 */

	obj_desc->common.data_type      = ACPI_DESC_TYPE_INTERNAL;
	obj_desc->common.flags          = AOPOBJ_STATIC_ALLOCATION;
	obj_desc->common.reference_count = 1;

	return;
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_get_simple_object_size
 *
 * PARAMETERS:  *Internal_obj   - Pointer to the object we are examining
 *              *Ret_length     - Where the length is returned
 *
 * RETURN:      Status          - the status of the call
 *
 * DESCRIPTION: This function is called to determine the space required to
 *              contain a simple object for return to an API user.
 *
 *              The length includes the object structure plus any additional
 *              needed space.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_cm_get_simple_object_size (
	ACPI_OPERAND_OBJECT     *internal_obj,
	u32                     *obj_length)
{
	u32                     length;
	ACPI_STATUS             status = AE_OK;


	/* Handle a null object (Could be a uninitialized package element -- which is legal) */

	if (!internal_obj) {
		*obj_length = 0;
		return (AE_OK);
	}


	/* Start with the length of the Acpi object */

	length = sizeof (ACPI_OBJECT);

	if (VALID_DESCRIPTOR_TYPE (internal_obj, ACPI_DESC_TYPE_NAMED)) {
		/* Object is a named object (reference), just return the length */

		*obj_length = (u32) ROUND_UP_TO_NATIVE_WORD (length);
		return (status);
	}


	/*
	 * The final length depends on the object type
	 * Strings and Buffers are packed right up against the parent object and
	 * must be accessed bytewise or there may be alignment problems.
	 *
	 * TBD:[Investigate] do strings and buffers require alignment also?
	 */

	switch (internal_obj->common.type)
	{

	case ACPI_TYPE_STRING:

		length += internal_obj->string.length + 1;
		break;


	case ACPI_TYPE_BUFFER:

		length += internal_obj->buffer.length;
		break;


	case ACPI_TYPE_NUMBER:
	case ACPI_TYPE_PROCESSOR:
	case ACPI_TYPE_POWER:

		/*
		 * No extra data for these types
		 */
		break;


	case INTERNAL_TYPE_REFERENCE:

		/*
		 * The only type that should be here is opcode AML_NAMEPATH_OP -- since
		 * this means an object reference
		 */
		if (internal_obj->reference.op_code != AML_NAMEPATH_OP) {
			status = AE_TYPE;
		}
		break;


	default:

		status = AE_TYPE;
		break;
	}


	/*
	 * Account for the space required by the object rounded up to the next
	 * multiple of the machine word size.  This keeps each object aligned
	 * on a machine word boundary. (preventing alignment faults on some
	 * machines.)
	 */
	*obj_length = (u32) ROUND_UP_TO_NATIVE_WORD (length);

	return (status);
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_get_package_object_size
 *
 * PARAMETERS:  *Internal_obj   - Pointer to the object we are examining
 *              *Ret_length     - Where the length is returned
 *
 * RETURN:      Status          - the status of the call
 *
 * DESCRIPTION: This function is called to determine the space required to contain
 *              a package object for return to an API user.
 *
 *              This is moderately complex since a package contains other objects
 *              including packages.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_cm_get_package_object_size (
	ACPI_OPERAND_OBJECT     *internal_obj,
	u32                     *obj_length)
{

	ACPI_OPERAND_OBJECT     *this_internal_obj;
	ACPI_OPERAND_OBJECT     *parent_obj[MAX_PACKAGE_DEPTH];
	ACPI_OPERAND_OBJECT     *this_parent;
	u32                     this_index;
	u32                     index[MAX_PACKAGE_DEPTH];
	u32                     length = 0;
	u32                     object_space;
	u32                     current_depth = 0;
	u32                     package_count = 1;
	ACPI_STATUS             status;


	/* Init the package stack TBD: replace with linked list */

	MEMSET(parent_obj, 0, MAX_PACKAGE_DEPTH);
	MEMSET(index, 0, MAX_PACKAGE_DEPTH);

	parent_obj[0] = internal_obj;

	while (1) {
		this_parent     = parent_obj[current_depth];
		this_index      = index[current_depth];
		this_internal_obj = this_parent->package.elements[this_index];


		/*
		 * Check for 1) An uninitialized package element.  It is completely
		 *              legal to declare a package and leave it uninitialized
		 *           2) Any type other than a package.  Packages are handled
		 *              below.
		 */

		if ((!this_internal_obj) ||
			(!IS_THIS_OBJECT_TYPE (this_internal_obj, ACPI_TYPE_PACKAGE)))
		{
			/*
			 * Simple object - just get the size (Null object/entry handled
			 *  also)
			 */

			status =
				acpi_cm_get_simple_object_size (this_internal_obj, &object_space);

			if (ACPI_FAILURE (status)) {
				return (status);
			}

			length += object_space;

			index[current_depth]++;
			while (index[current_depth] >=
				parent_obj[current_depth]->package.count)
			{
				/*
				 * We've handled all of the objects at
				 * this level,  This means that we have
				 * just completed a package.  That package
				 * may have contained one or more packages
				 * itself.
				 */
				if (current_depth == 0) {
					/*
					 * We have handled all of the objects
					 * in the top level package just add the
					 * length of the package objects and
					 * get out. Round up to the next machine
					 * word.
					 */
					length +=
						ROUND_UP_TO_NATIVE_WORD (
								sizeof (ACPI_OBJECT)) *
								package_count;

					*obj_length = length;

					return (AE_OK);
				}

				/*
				 * Go back up a level and move the index
				 * past the just completed package object.
				 */
				current_depth--;
				index[current_depth]++;
			}
		}

		else {
			/*
			 * This object is a package
			 * -- go one level deeper
			 */
			package_count++;
			if (current_depth < MAX_PACKAGE_DEPTH-1) {
				current_depth++;
				parent_obj[current_depth] = this_internal_obj;
				index[current_depth]    = 0;
			}

			else {
				/*
				 * Too many nested levels of packages for us
				 * to handle
				 */

				return (AE_LIMIT);
			}
		}
	}
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_get_object_size
 *
 * PARAMETERS:  *Internal_obj   - Pointer to the object we are examining
 *              *Ret_length     - Where the length will be returned
 *
 * RETURN:      Status          - the status of the call
 *
 * DESCRIPTION: This function is called to determine the space required to
 *              contain an object for return to an API user.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_cm_get_object_size(
	ACPI_OPERAND_OBJECT     *internal_obj,
	u32                     *obj_length)
{
	ACPI_STATUS             status;


	if ((VALID_DESCRIPTOR_TYPE (internal_obj, ACPI_DESC_TYPE_INTERNAL)) &&
		(IS_THIS_OBJECT_TYPE (internal_obj, ACPI_TYPE_PACKAGE)))
	{
		status =
			acpi_cm_get_package_object_size (internal_obj, obj_length);
	}

	else {
		status =
			acpi_cm_get_simple_object_size (internal_obj, obj_length);
	}

	return (status);
}