nsutils.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

/******************************************************************************
 *
 * Module Name: nsutils - Utilities for accessing ACPI namespace, accessing
 *                        parents and siblings and Scope manipulation
 *              $Revision: 92 $
 *
 *****************************************************************************/

/*
 *  Copyright (C) 2000, 2001 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 "acnamesp.h"
#include "acinterp.h"
#include "amlcode.h"
#include "actables.h"

#define _COMPONENT          ACPI_NAMESPACE
	 MODULE_NAME         ("nsutils")


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ns_valid_root_prefix
 *
 * PARAMETERS:  Prefix          - Character to be checked
 *
 * RETURN:      TRUE if a valid prefix
 *
 * DESCRIPTION: Check if a character is a valid ACPI Root prefix
 *
 ******************************************************************************/

u8
acpi_ns_valid_root_prefix (
	NATIVE_CHAR             prefix)
{

	return ((u8) (prefix == '\\'));
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ns_valid_path_separator
 *
 * PARAMETERS:  Sep              - Character to be checked
 *
 * RETURN:      TRUE if a valid path separator
 *
 * DESCRIPTION: Check if a character is a valid ACPI path separator
 *
 ******************************************************************************/

u8
acpi_ns_valid_path_separator (
	NATIVE_CHAR             sep)
{

	return ((u8) (sep == '.'));
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ns_get_type
 *
 * PARAMETERS:  Handle              - Parent Node to be examined
 *
 * RETURN:      Type field from Node whose handle is passed
 *
 ******************************************************************************/

acpi_object_type8
acpi_ns_get_type (
	acpi_namespace_node     *node)
{
	FUNCTION_TRACE ("Ns_get_type");


	if (!node) {
		REPORT_WARNING (("Ns_get_type: Null Node ptr"));
		return_VALUE (ACPI_TYPE_ANY);
	}

	return_VALUE (node->type);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ns_local
 *
 * PARAMETERS:  Type            - A namespace object type
 *
 * RETURN:      LOCAL if names must be found locally in objects of the
 *              passed type, 0 if enclosing scopes should be searched
 *
 ******************************************************************************/

u32
acpi_ns_local (
	acpi_object_type8       type)
{
	FUNCTION_TRACE ("Ns_local");


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

		REPORT_WARNING (("Ns_local: Invalid Object Type\n"));
		return_VALUE (NSP_NORMAL);
	}

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


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ns_get_internal_name_length
 *
 * PARAMETERS:  Info            - Info struct initialized with the
 *                                external name pointer.
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Calculate the length of the internal (AML) namestring
 *              corresponding to the external (ASL) namestring.
 *
 ******************************************************************************/

acpi_status
acpi_ns_get_internal_name_length (
	acpi_namestring_info    *info)
{
	NATIVE_CHAR             *next_external_char;
	u32                     i;


	FUNCTION_ENTRY ();


	next_external_char = info->external_name;
	info->num_carats = 0;
	info->num_segments = 0;
	info->fully_qualified = FALSE;

	/*
	 * For the internal name, the required length is 4 bytes
	 * per segment, plus 1 each for Root_prefix, Multi_name_prefix_op,
	 * segment count, trailing null (which is not really needed,
	 * but no there's harm in putting it there)
	 *
	 * strlen() + 1 covers the first Name_seg, which has no
	 * path separator
	 */
	if (acpi_ns_valid_root_prefix (next_external_char[0])) {
		info->fully_qualified = TRUE;
		next_external_char++;
	}

	else {
		/*
		 * Handle Carat prefixes
		 */
		while (*next_external_char == '^') {
			info->num_carats++;
			next_external_char++;
		}
	}

	/*
	 * Determine the number of ACPI name "segments" by counting
	 * the number of path separators within the string.  Start
	 * with one segment since the segment count is (# separators)
	 * + 1, and zero separators is ok.
	 */
	if (*next_external_char) {
		info->num_segments = 1;
		for (i = 0; next_external_char[i]; i++) {
			if (acpi_ns_valid_path_separator (next_external_char[i])) {
				info->num_segments++;
			}
		}
	}

	info->length = (ACPI_NAME_SIZE * info->num_segments) +
			  4 + info->num_carats;

	info->next_external_char = next_external_char;

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ns_build_internal_name
 *
 * PARAMETERS:  Info            - Info struct fully initialized
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Construct the internal (AML) namestring
 *              corresponding to the external (ASL) namestring.
 *
 ******************************************************************************/

acpi_status
acpi_ns_build_internal_name (
	acpi_namestring_info    *info)
{
	u32                     num_segments = info->num_segments;
	NATIVE_CHAR             *internal_name = info->internal_name;
	NATIVE_CHAR             *external_name = info->next_external_char;
	NATIVE_CHAR             *result = NULL;
	u32                     i;


	FUNCTION_TRACE ("Ns_build_internal_name");


	/* Setup the correct prefixes, counts, and pointers */

	if (info->fully_qualified) {
		internal_name[0] = '\\';

		if (num_segments <= 1) {
			result = &internal_name[1];
		}
		else if (num_segments == 2) {
			internal_name[1] = AML_DUAL_NAME_PREFIX;
			result = &internal_name[2];
		}
		else {
			internal_name[1] = AML_MULTI_NAME_PREFIX_OP;
			internal_name[2] = (char) num_segments;
			result = &internal_name[3];
		}
	}

	else {
		/*
		 * Not fully qualified.
		 * Handle Carats first, then append the name segments
		 */
		i = 0;
		if (info->num_carats) {
			for (i = 0; i < info->num_carats; i++) {
				internal_name[i] = '^';
			}
		}

		if (num_segments == 1) {
			result = &internal_name[i];
		}

		else if (num_segments == 2) {
			internal_name[i] = AML_DUAL_NAME_PREFIX;
			result = &internal_name[i+1];
		}

		else {
			internal_name[i] = AML_MULTI_NAME_PREFIX_OP;
			internal_name[i+1] = (char) num_segments;
			result = &internal_name[i+2];
		}
	}


	/* Build the name (minus path separators) */

	for (; num_segments; num_segments--) {
		for (i = 0; i < ACPI_NAME_SIZE; i++) {
			if (acpi_ns_valid_path_separator (*external_name) ||
			   (*external_name == 0)) {
				/* Pad the segment with underscore(s) if segment is short */

				result[i] = '_';
			}

			else {
				/* Convert the character to uppercase and save it */

				result[i] = (char) TOUPPER (*external_name);
				external_name++;
			}
		}

		/* Now we must have a path separator, or the pathname is bad */

		if (!acpi_ns_valid_path_separator (*external_name) &&
			(*external_name != 0)) {
			return_ACPI_STATUS (AE_BAD_PARAMETER);
		}

		/* Move on the next segment */

		external_name++;
		result += ACPI_NAME_SIZE;
	}


	/* Terminate the string */

	*result = 0;

	if (info->fully_qualified) {
		ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "returning [%p] (abs) \"\\%s\"\n",
			internal_name, &internal_name[0]));
	}
	else {
		ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "returning [%p] (rel) \"%s\"\n",
			internal_name, &internal_name[2]));
	}

	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ns_internalize_name
 *
 * PARAMETERS:  *External_name          - External representation of name
 *              **Converted Name        - Where to return the resulting
 *                                        internal represention of the name
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an external representation (e.g. "\_PR_.CPU0")
 *              to internal form (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
 *
 *******************************************************************************/

acpi_status
acpi_ns_internalize_name (
	NATIVE_CHAR             *external_name,
	NATIVE_CHAR             **converted_name)
{
	NATIVE_CHAR             *internal_name;
	acpi_namestring_info    info;
	acpi_status             status;


	FUNCTION_TRACE ("Ns_internalize_name");


	if ((!external_name)     ||
		(*external_name == 0) ||
		(!converted_name)) {
		return_ACPI_STATUS (AE_BAD_PARAMETER);
	}


	/* Get the length of the new internal name */

	info.external_name = external_name;
	acpi_ns_get_internal_name_length (&info);

	/* We need a segment to store the internal  name */

	internal_name = ACPI_MEM_CALLOCATE (info.length);
	if (!internal_name) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	/* 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)
{
	u32                     prefix_length = 0;
	u32                     names_index = 0;
	u32                     names_count = 0;
	u32                     i = 0;
	u32                     j = 0;


	FUNCTION_TRACE ("Ns_externalize_name");


	if (!internal_name_length   ||
		!internal_name          ||
		!converted_name_length  ||
		!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;
			}
		}

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

		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]) {

		/* <count> 4-byte names */

		case AML_MULTI_NAME_PREFIX_OP:
			names_index = prefix_length + 2;
			names_count = (u32) internal_name[prefix_length + 1];
			break;


		/* two 4-byte names */

		case AML_DUAL_NAME_PREFIX:
			names_index = prefix_length + 1;