nsutils.c

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		/* one 4-byte name */

		default:
			names_index = prefix_length;
			names_count = 1;
			break;
		}
	}

	/*
	 * Calculate the length of Converted_name, which equals the length
	 * of the prefix, length of all object names, length of any required
	 * punctuation ('.') between object names, plus the NULL terminator.
	 */
	*converted_name_length = prefix_length + (4 * names_count) +
			   ((names_count > 0) ? (names_count - 1) : 0) + 1;

	/*
	 * Check to see if we're still in bounds.  If not, there's a problem
	 * with Internal_name (invalid format).
	 */
	if (*converted_name_length > internal_name_length) {
		REPORT_ERROR (("Ns_externalize_name: Invalid internal name\n"));
		return (AE_BAD_PATHNAME);
	}

	/*
	 * Build Converted_name...
	 */

	(*converted_name) = acpi_cm_callocate (*converted_name_length);
	if (!(*converted_name)) {
		return (AE_NO_MEMORY);
	}

	j = 0;

	for (i = 0; i < prefix_length; i++) {
		(*converted_name)[j++] = internal_name[i];
	}

	if (names_count > 0) {
		for (i = 0; i < names_count; i++) {
			if (i > 0) {
				(*converted_name)[j++] = '.';
			}

			(*converted_name)[j++] = internal_name[names_index++];
			(*converted_name)[j++] = internal_name[names_index++];
			(*converted_name)[j++] = internal_name[names_index++];
			(*converted_name)[j++] = internal_name[names_index++];
		}
	}

	return (AE_OK);
}


/****************************************************************************
 *
 * FUNCTION:    Acpi_ns_convert_handle_to_entry
 *
 * PARAMETERS:  Handle          - Handle to be converted to an Node
 *
 * RETURN:      A Name table entry pointer
 *
 * DESCRIPTION: Convert a namespace handle to a real Node
 *
 ****************************************************************************/

ACPI_NAMESPACE_NODE *
acpi_ns_convert_handle_to_entry (
	ACPI_HANDLE             handle)
{

	/*
	 * Simple implementation for now;
	 * TBD: [Future] Real integer handles allow for more verification
	 * and keep all pointers within this subsystem!
	 */

	if (!handle) {
		return (NULL);
	}

	if (handle == ACPI_ROOT_OBJECT) {
		return (acpi_gbl_root_node);
	}


	/* We can at least attempt to verify the handle */

	if (!VALID_DESCRIPTOR_TYPE (handle, ACPI_DESC_TYPE_NAMED)) {
		return (NULL);
	}

	return ((ACPI_NAMESPACE_NODE *) handle);
}


/****************************************************************************
 *
 * FUNCTION:    Acpi_ns_convert_entry_to_handle
 *
 * PARAMETERS:  Node          - Node to be converted to a Handle
 *
 * RETURN:      An USER ACPI_HANDLE
 *
 * DESCRIPTION: Convert a real Node to a namespace handle
 *
 ****************************************************************************/

ACPI_HANDLE
acpi_ns_convert_entry_to_handle (
	ACPI_NAMESPACE_NODE         *node)
{


	/*
	 * Simple implementation for now;
	 * TBD: [Future] Real integer handles allow for more verification
	 * and keep all pointers within this subsystem!
	 */

	return ((ACPI_HANDLE) node);


/* ---------------------------------------------------

	if (!Node) {
		return (NULL);
	}

	if (Node == Acpi_gbl_Root_node) {
		return (ACPI_ROOT_OBJECT);
	}


	return ((ACPI_HANDLE) Node);
------------------------------------------------------*/
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_ns_terminate
 *
 * PARAMETERS:  none
 *
 * RETURN:      none
 *
 * DESCRIPTION: free memory allocated for table storage.
 *
 ******************************************************************************/

void
acpi_ns_terminate (void)
{
	ACPI_OPERAND_OBJECT     *obj_desc;
	ACPI_NAMESPACE_NODE     *this_node;


	this_node = acpi_gbl_root_node;

	/*
	 * 1) Free the entire namespace -- all objects, tables, and stacks
	 */
	/*
	 * Delete all objects linked to the root
	 * (additional table descriptors)
	 */

	acpi_ns_delete_namespace_subtree (this_node);

	/* Detach any object(s) attached to the root */

	obj_desc = acpi_ns_get_attached_object (this_node);
	if (obj_desc) {
		acpi_ns_detach_object (this_node);
		acpi_cm_remove_reference (obj_desc);
	}

	acpi_ns_delete_children (this_node);


	/*
	 * 2) Now we can delete the ACPI tables
	 */

	acpi_tb_delete_acpi_tables ();

	return;
}


/****************************************************************************
 *
 * FUNCTION:    Acpi_ns_opens_scope
 *
 * PARAMETERS:  Type        - A valid namespace type
 *
 * RETURN:      NEWSCOPE if the passed type "opens a name scope" according
 *              to the ACPI specification, else 0
 *
 ***************************************************************************/

u32
acpi_ns_opens_scope (
	OBJECT_TYPE_INTERNAL    type)
{

	if (!acpi_cm_valid_object_type (type)) {
		/* type code out of range  */

		REPORT_WARNING (("Ns_opens_scope: Invalid Object Type\n"));
		return (NSP_NORMAL);
	}

	return (((u32) acpi_gbl_ns_properties[type]) & NSP_NEWSCOPE);
}


/****************************************************************************
 *
 * FUNCTION:    Acpi_ns_get_node
 *
 * PARAMETERS:  *Pathname   - Name to be found, in external (ASL) format. The
 *                            \ (backslash) and ^ (carat) prefixes, and the
 *                            . (period) to separate segments are supported.
 *              Start_node  - Root of subtree to be searched, or NS_ALL for the
 *                            root of the name space.  If Name is fully
 *                            qualified (first s8 is '\'), the passed value
 *                            of Scope will not be accessed.
 *              Return_node - Where the Node is returned
 *
 * DESCRIPTION: Look up a name relative to a given scope and return the
 *              corresponding Node.  NOTE: Scope can be null.
 *
 * MUTEX:       Locks namespace
 *
 ***************************************************************************/

ACPI_STATUS
acpi_ns_get_node (
	NATIVE_CHAR             *pathname,
	ACPI_NAMESPACE_NODE     *start_node,
	ACPI_NAMESPACE_NODE     **return_node)
{
	ACPI_GENERIC_STATE      scope_info;
	ACPI_STATUS             status;
	NATIVE_CHAR             *internal_path = NULL;


	/* Ensure that the namespace has been initialized */

	if (!acpi_gbl_root_node) {
		return (AE_NO_NAMESPACE);
	}

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


	/* Convert path to internal representation */

	status = acpi_ns_internalize_name (pathname, &internal_path);
	if (ACPI_FAILURE (status)) {
		return (status);
	}


	acpi_cm_acquire_mutex (ACPI_MTX_NAMESPACE);

	/* Setup lookup scope (search starting point) */

	scope_info.scope.node = start_node;

	/* Lookup the name in the namespace */

	status = acpi_ns_lookup (&scope_info, internal_path,
			 ACPI_TYPE_ANY, IMODE_EXECUTE,
			 NS_NO_UPSEARCH | NS_DONT_OPEN_SCOPE,
			 NULL, return_node);



	acpi_cm_release_mutex (ACPI_MTX_NAMESPACE);

	/* Cleanup */

	acpi_cm_free (internal_path);

	return (status);
}


/****************************************************************************
 *
 * FUNCTION:    Acpi_ns_find_parent_name
 *
 * PARAMETERS:  *Child_node            - Named Obj whose name is to be found
 *
 * RETURN:      The ACPI name
 *
 * DESCRIPTION: Search for the given obj in its parent scope and return the
 *              name segment, or "????" if the parent name can't be found
 *              (which "should not happen").
 *
 ***************************************************************************/

ACPI_NAME
acpi_ns_find_parent_name (
	ACPI_NAMESPACE_NODE     *child_node)
{
	ACPI_NAMESPACE_NODE     *parent_node;


	if (child_node) {
		/* Valid entry.  Get the parent Node */

		parent_node = acpi_ns_get_parent_object (child_node);
		if (parent_node) {
			if (parent_node->name) {
				return (parent_node->name);
			}
		}

	}


	return (ACPI_UNKNOWN_NAME);
}


/****************************************************************************
 *
 * FUNCTION:    Acpi_ns_get_parent_object
 *
 * PARAMETERS:  Node       - Current table entry
 *
 * RETURN:      Parent entry of the given entry
 *
 * DESCRIPTION: Obtain the parent entry for a given entry in the namespace.
 *
 ***************************************************************************/


ACPI_NAMESPACE_NODE *
acpi_ns_get_parent_object (
	ACPI_NAMESPACE_NODE     *node)
{


	if (!node) {
		return (NULL);
	}

	/*
	 * Walk to the end of this peer list.
	 * The last entry is marked with a flag and the peer
	 * pointer is really a pointer back to the parent.
	 * This saves putting a parent back pointer in each and
	 * every named object!
	 */

	while (!(node->flags & ANOBJ_END_OF_PEER_LIST)) {
		node = node->peer;
	}


	return (node->peer);
}


/****************************************************************************
 *
 * FUNCTION:    Acpi_ns_get_next_valid_object
 *
 * PARAMETERS:  Node       - Current table entry
 *
 * RETURN:      Next valid object in the table.  NULL if no more valid
 *              objects
 *
 * DESCRIPTION: Find the next valid object within a name table.
 *              Useful for implementing NULL-end-of-list loops.
 *
 ***************************************************************************/


ACPI_NAMESPACE_NODE *
acpi_ns_get_next_valid_object (
	ACPI_NAMESPACE_NODE     *node)
{

	/* If we are at the end of this peer list, return NULL */

	if (node->flags & ANOBJ_END_OF_PEER_LIST) {
		return NULL;
	}

	/* Otherwise just return the next peer */

	return (node->peer);
}