exconvrt.c

linux-2.4.29操作系统的源码

/******************************************************************************
 *
 * Module Name: exconvrt - Object conversion routines
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2004, R. Byron Moore
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */


#include <acpi/acpi.h>
#include <acpi/acinterp.h>
#include <acpi/amlcode.h>


#define _COMPONENT          ACPI_EXECUTER
	 ACPI_MODULE_NAME    ("exconvrt")


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_to_integer
 *
 * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
 *                                Integer, Buffer, or String
 *              result_desc     - Where the new Integer object is returned
 *              walk_state      - Current method state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an ACPI Object to an integer.
 *
 ******************************************************************************/

acpi_status
acpi_ex_convert_to_integer (
	union acpi_operand_object       *obj_desc,
	union acpi_operand_object       **result_desc,
	struct acpi_walk_state          *walk_state)
{
	u32                             i;
	union acpi_operand_object       *ret_desc;
	u32                             count;
	u8                              *pointer;
	acpi_integer                    result;
	acpi_status                     status;


	ACPI_FUNCTION_TRACE_PTR ("ex_convert_to_integer", obj_desc);


	switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
	case ACPI_TYPE_INTEGER:
		*result_desc = obj_desc;
		return_ACPI_STATUS (AE_OK);

	case ACPI_TYPE_STRING:
		pointer = (u8 *) obj_desc->string.pointer;
		count   = obj_desc->string.length;
		break;

	case ACPI_TYPE_BUFFER:
		pointer = obj_desc->buffer.pointer;
		count   = obj_desc->buffer.length;
		break;

	default:
		return_ACPI_STATUS (AE_TYPE);
	}

	/*
	 * Convert the buffer/string to an integer.  Note that both buffers and
	 * strings are treated as raw data - we don't convert ascii to hex for
	 * strings.
	 *
	 * There are two terminating conditions for the loop:
	 * 1) The size of an integer has been reached, or
	 * 2) The end of the buffer or string has been reached
	 */
	result = 0;

	/* Transfer no more than an integer's worth of data */

	if (count > acpi_gbl_integer_byte_width) {
		count = acpi_gbl_integer_byte_width;
	}

	/*
	 * String conversion is different than Buffer conversion
	 */
	switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
	case ACPI_TYPE_STRING:

		/*
		 * Convert string to an integer
		 * String must be hexadecimal as per the ACPI specification
		 */
		status = acpi_ut_strtoul64 ((char *) pointer, 16, &result);
		if (ACPI_FAILURE (status)) {
			return_ACPI_STATUS (status);
		}
		break;


	case ACPI_TYPE_BUFFER:

		/*
		 * Buffer conversion - we simply grab enough raw data from the
		 * buffer to fill an integer
		 */
		for (i = 0; i < count; i++) {
			/*
			 * Get next byte and shift it into the Result.
			 * Little endian is used, meaning that the first byte of the buffer
			 * is the LSB of the integer
			 */
			result |= (((acpi_integer) pointer[i]) << (i * 8));
		}
		break;


	default:
		/* No other types can get here */
		break;
	}

	/*
	 * Create a new integer
	 */
	ret_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
	if (!ret_desc) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	/* Save the Result */

	ret_desc->integer.value = result;

	/*
	 * If we are about to overwrite the original object on the operand stack,
	 * we must remove a reference on the original object because we are
	 * essentially removing it from the stack.
	 */
	if (*result_desc == obj_desc) {
		if (walk_state->opcode != AML_STORE_OP) {
			acpi_ut_remove_reference (obj_desc);
		}
	}

	*result_desc = ret_desc;
	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_to_buffer
 *
 * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
 *                                Integer, Buffer, or String
 *              result_desc     - Where the new buffer object is returned
 *              walk_state      - Current method state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an ACPI Object to a Buffer
 *
 ******************************************************************************/

acpi_status
acpi_ex_convert_to_buffer (
	union acpi_operand_object       *obj_desc,
	union acpi_operand_object       **result_desc,
	struct acpi_walk_state          *walk_state)
{
	union acpi_operand_object       *ret_desc;
	u32                             i;
	u8                              *new_buf;


	ACPI_FUNCTION_TRACE_PTR ("ex_convert_to_buffer", obj_desc);


	switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
	case ACPI_TYPE_BUFFER:

		/* No conversion necessary */

		*result_desc = obj_desc;
		return_ACPI_STATUS (AE_OK);


	case ACPI_TYPE_INTEGER:

		/*
		 * Create a new Buffer object.
		 * Need enough space for one integer
		 */
		ret_desc = acpi_ut_create_buffer_object (acpi_gbl_integer_byte_width);
		if (!ret_desc) {
			return_ACPI_STATUS (AE_NO_MEMORY);
		}

		/* Copy the integer to the buffer */

		new_buf = ret_desc->buffer.pointer;
		for (i = 0; i < acpi_gbl_integer_byte_width; i++) {
			new_buf[i] = (u8) (obj_desc->integer.value >> (i * 8));
		}
		break;


	case ACPI_TYPE_STRING:

		/*
		 * Create a new Buffer object
		 * Size will be the string length
		 */
		ret_desc = acpi_ut_create_buffer_object ((acpi_size) obj_desc->string.length);
		if (!ret_desc) {
			return_ACPI_STATUS (AE_NO_MEMORY);
		}

		/* Copy the string to the buffer */

		new_buf = ret_desc->buffer.pointer;
		ACPI_STRNCPY ((char *) new_buf, (char *) obj_desc->string.pointer,
			obj_desc->string.length);
		break;


	default:
		return_ACPI_STATUS (AE_TYPE);
	}

	/* Mark buffer initialized */

	ret_desc->common.flags |= AOPOBJ_DATA_VALID;

	/*
	 * If we are about to overwrite the original object on the operand stack,
	 * we must remove a reference on the original object because we are
	 * essentially removing it from the stack.
	 */
	if (*result_desc == obj_desc) {
		if (walk_state->opcode != AML_STORE_OP) {
			acpi_ut_remove_reference (obj_desc);
		}
	}

	*result_desc = ret_desc;
	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_ascii
 *
 * PARAMETERS:  Integer         - Value to be converted
 *              Base            - 10 or 16
 *              String          - Where the string is returned
 *              data_width      - Size of data item to be converted
 *
 * RETURN:      Actual string length
 *
 * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
 *
 ******************************************************************************/

u32
acpi_ex_convert_to_ascii (
	acpi_integer                    integer,
	u32                             base,
	u8                              *string,
	u8                              data_width)
{
	u32                             i;
	u32                             j;
	u32                             k = 0;
	char                            hex_digit;
	acpi_integer                    digit;
	u32                             remainder;
	u32                             length;
	u8                              leading_zero;


	ACPI_FUNCTION_ENTRY ();


	if (data_width < sizeof (acpi_integer)) {
		leading_zero = FALSE;
		length = data_width;
	}
	else {
		leading_zero = TRUE;
		length = sizeof (acpi_integer);
	}

	switch (base) {
	case 10:

		remainder = 0;
		for (i = ACPI_MAX_DECIMAL_DIGITS; i > 0; i--) {
			/* Divide by nth factor of 10 */

			digit = integer;
			for (j = 0; j < i; j++) {
				(void) acpi_ut_short_divide (&digit, 10, &digit, &remainder);
			}

			/* Create the decimal digit */

			if (remainder != 0) {
				leading_zero = FALSE;
			}

			if (!leading_zero) {