nsutils.c

h内核

	/* Build the name */

	info.internal_name = internal_name;
	status = acpi_ns_build_internal_name (&info);
	if (ACPI_FAILURE (status)) {
		ACPI_MEM_FREE (internal_name);
		return_ACPI_STATUS (status);
	}

	*converted_name = internal_name;
	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_externalize_name
 *
 * PARAMETERS:  *internal_name         - Internal representation of name
 *              **converted_name       - Where to return the resulting
 *                                       external representation of name
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert internal name (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
 *              to its external form (e.g. "\_PR_.CPU0")
 *
 ******************************************************************************/

acpi_status
acpi_ns_externalize_name (
	u32                             internal_name_length,
	char                            *internal_name,
	u32                             *converted_name_length,
	char                            **converted_name)
{
	acpi_native_uint                names_index = 0;
	acpi_native_uint                num_segments = 0;
	acpi_native_uint                required_length;
	acpi_native_uint                prefix_length = 0;
	acpi_native_uint                i = 0;
	acpi_native_uint                j = 0;


	ACPI_FUNCTION_TRACE ("ns_externalize_name");


	if (!internal_name_length   ||
		!internal_name          ||
		!converted_name) {
		return_ACPI_STATUS (AE_BAD_PARAMETER);
	}

	/*
	 * Check for a prefix (one '\' | one or more '^').
	 */
	switch (internal_name[0]) {
	case '\\':
		prefix_length = 1;
		break;

	case '^':
		for (i = 0; i < internal_name_length; i++) {
			if (internal_name[i] == '^') {
				prefix_length = i + 1;
			}
			else {
				break;
			}
		}

		if (i == internal_name_length) {
			prefix_length = i;
		}

		break;

	default:
		break;
	}

	/*
	 * Check for object names.  Note that there could be 0-255 of these
	 * 4-byte elements.
	 */
	if (prefix_length < internal_name_length) {
		switch (internal_name[prefix_length]) {
		case AML_MULTI_NAME_PREFIX_OP:

			/* <count> 4-byte names */

			names_index = prefix_length + 2;
			num_segments = (acpi_native_uint) (u8)
					   internal_name[(acpi_native_uint) (prefix_length + 1)];
			break;

		case AML_DUAL_NAME_PREFIX:

			/* Two 4-byte names */

			names_index = prefix_length + 1;
			num_segments = 2;
			break;

		case 0:

			/* null_name */

			names_index = 0;
			num_segments = 0;
			break;

		default:

			/* one 4-byte name */

			names_index = prefix_length;
			num_segments = 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.
	 */
	required_length = prefix_length + (4 * num_segments) +
			   ((num_segments > 0) ? (num_segments - 1) : 0) + 1;

	/*
	 * Check to see if we're still in bounds.  If not, there's a problem
	 * with internal_name (invalid format).
	 */
	if (required_length > internal_name_length) {
		ACPI_REPORT_ERROR (("ns_externalize_name: Invalid internal name\n"));
		return_ACPI_STATUS (AE_BAD_PATHNAME);
	}

	/*
	 * Build converted_name
	 */
	*converted_name = ACPI_MEM_CALLOCATE (required_length);
	if (!(*converted_name)) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	j = 0;

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

	if (num_segments > 0) {
		for (i = 0; i < num_segments; 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++];
		}
	}

	if (converted_name_length) {
		*converted_name_length = (u32) required_length;
	}

	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_map_handle_to_node
 *
 * PARAMETERS:  Handle          - Handle to be converted to an Node
 *
 * RETURN:      A Name table entry pointer
 *
 * DESCRIPTION: Convert a namespace handle to a real Node
 *
 * Note: Real integer handles allow for more verification
 *       and keep all pointers within this subsystem.
 *
 ******************************************************************************/

struct acpi_namespace_node *
acpi_ns_map_handle_to_node (
	acpi_handle                     handle)
{

	ACPI_FUNCTION_ENTRY ();


	/*
	 * Simple implementation.
	 */
	if (!handle) {
		return (NULL);
	}

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

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

	if (ACPI_GET_DESCRIPTOR_TYPE (handle) != ACPI_DESC_TYPE_NAMED) {
		return (NULL);
	}

	return ((struct acpi_namespace_node *) handle);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_convert_entry_to_handle
 *
 * PARAMETERS:  Node          - Node to be converted to a Handle
 *
 * RETURN:      A user handle
 *
 * DESCRIPTION: Convert a real Node to a namespace handle
 *
 ******************************************************************************/

acpi_handle
acpi_ns_convert_entry_to_handle (
	struct acpi_namespace_node          *node)
{


	/*
	 * Simple implementation for now;
	 */
	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)
{
	union acpi_operand_object       *obj_desc;


	ACPI_FUNCTION_TRACE ("ns_terminate");


	/*
	 * 1) Free the entire namespace -- all nodes and objects
	 *
	 * Delete all object descriptors attached to namepsace nodes
	 */
	acpi_ns_delete_namespace_subtree (acpi_gbl_root_node);

	/* Detach any objects attached to the root */

	obj_desc = acpi_ns_get_attached_object (acpi_gbl_root_node);
	if (obj_desc) {
		acpi_ns_detach_object (acpi_gbl_root_node);
	}

	ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Namespace freed\n"));

	/*
	 * 2) Now we can delete the ACPI tables
	 */
	acpi_tb_delete_all_tables ();
	ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "ACPI Tables freed\n"));

	return_VOID;
}


/*******************************************************************************
 *
 * 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 (
	acpi_object_type                type)
{
	ACPI_FUNCTION_TRACE_STR ("ns_opens_scope", acpi_ut_get_type_name (type));


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

		ACPI_REPORT_WARNING (("ns_opens_scope: Invalid Object Type %X\n", type));
		return_VALUE (ACPI_NS_NORMAL);
	}

	return_VALUE (((u32) acpi_gbl_ns_properties[type]) & ACPI_NS_NEWSCOPE);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_node_by_path
 *
 * 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.
 *              Flags       - Used to indicate whether to perform upsearch or
 *                            not.
 *              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_by_path (
	char                            *pathname,
	struct acpi_namespace_node      *start_node,
	u32                             flags,
	struct acpi_namespace_node      **return_node)
{
	union acpi_generic_state        scope_info;
	acpi_status                     status;
	char                            *internal_path = NULL;


	ACPI_FUNCTION_TRACE_PTR ("ns_get_node_by_path", pathname);


	if (pathname) {
		/* Convert path to internal representation */

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

	/* Must lock namespace during lookup */

	status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE (status)) {
		goto cleanup;
	}

	/* 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, ACPI_IMODE_EXECUTE,
			 (flags | ACPI_NS_DONT_OPEN_SCOPE),
			 NULL, return_node);
	if (ACPI_FAILURE (status)) {
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "%s, %s\n",
				internal_path, acpi_format_exception (status)));
	}

	(void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);

cleanup:
	/* Cleanup */
	if (internal_path) {
		ACPI_MEM_FREE (internal_path);
	}
	return_ACPI_STATUS (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").
 *
 ******************************************************************************/
#ifdef ACPI_FUTURE_USAGE
acpi_name
acpi_ns_find_parent_name (
	struct acpi_namespace_node      *child_node)
{
	struct acpi_namespace_node      *parent_node;


	ACPI_FUNCTION_TRACE ("ns_find_parent_name");


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

		parent_node = acpi_ns_get_parent_node (child_node);
		if (parent_node) {
			ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
				"Parent of %p [%4.4s] is %p [%4.4s]\n",
				child_node, acpi_ut_get_node_name (child_node),
				parent_node, acpi_ut_get_node_name (parent_node)));

			if (parent_node->name.integer) {
				return_VALUE ((acpi_name) parent_node->name.integer);
			}
		}

		ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
			"Unable to find parent of %p (%4.4s)\n",
			child_node, acpi_ut_get_node_name (child_node)));
	}

	return_VALUE (ACPI_UNKNOWN_NAME);
}
#endif


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


struct acpi_namespace_node *
acpi_ns_get_parent_node (
	struct acpi_namespace_node      *node)
{
	ACPI_FUNCTION_ENTRY ();


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


struct acpi_namespace_node *
acpi_ns_get_next_valid_node (
	struct 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);
}