/*******************************************************************************
*
* Module Name: utstrtoul64 - string to 64-bit integer support
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2016, Intel Corp.
* 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 "accommon.h"
/*******************************************************************************
*
* The functions in this module satisfy the need for 64-bit string-to-integer
* conversions on both 32-bit and 64-bit platforms.
*
******************************************************************************/
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utstrtoul64")
/* Local prototypes */
static u64 acpi_ut_strtoul_base10(char *string, u32 flags);
static u64 acpi_ut_strtoul_base16(char *string, u32 flags);
/*******************************************************************************
*
* String conversion rules as written in the ACPI specification. The error
* conditions and behavior are different depending on the type of conversion.
*
*
* Implicit data type conversion: string-to-integer
* --------------------------------------------------
*
* Base is always 16. This is the ACPI_STRTOUL_BASE16 case.
*
* Example:
* Add ("BA98", Arg0, Local0)
*
* The integer is initialized to the value zero.
* The ASCII string is interpreted as a hexadecimal constant.
*
* 1) A "0x" prefix is not allowed. However, ACPICA allows this for
* compatibility with previous ACPICA. (NO ERROR)
*
* 2) Terminates when the size of an integer is reached (32 or 64 bits).
* (NO ERROR)
*
* 3) The first non-hex character terminates the conversion without error.
* (NO ERROR)
*
* 4) Conversion of a null (zero-length) string to an integer is not
* allowed. However, ACPICA allows this for compatibility with previous
* ACPICA. This conversion returns the value 0. (NO ERROR)
*
*
* Explicit data type conversion: to_integer() with string operand
* ---------------------------------------------------------------
*
* Base is either 10 (default) or 16 (with 0x prefix)
*
* Examples:
* to_integer ("1000")
* to_integer ("0xABCD")
*
* 1) Can be (must be) either a decimal or hexadecimal numeric string.
* A hex value must be prefixed by "0x" or it is interpreted as a decimal.
*
* 2) The value must not exceed the maximum of an integer value. ACPI spec
* states the behavior is "unpredictable", so ACPICA matches the behavior
* of the implicit conversion case.(NO ERROR)
*
* 3) Behavior on the first non-hex character is not specified by the ACPI
* spec, so ACPICA matches the behavior of the implicit conversion case
* and terminates. (NO ERROR)
*
* 4) A null (zero-length) string is illegal.
* However, ACPICA allows this for compatibility with previous ACPICA.
* This conversion returns the value 0. (NO ERROR)
*
******************************************************************************/
/*******************************************************************************
*
* FUNCTION: acpi_ut_strtoul64
*
* PARAMETERS: string - Null terminated input string
* flags - Conversion info, see below
* return_value - Where the converted integer is
* returned
*
* RETURN: Status and Converted value
*
* DESCRIPTION: Convert a string into an unsigned value. Performs either a
* 32-bit or 64-bit conversion, depending on the input integer
* size in Flags (often the current mode of the interpreter).
*
* Values for Flags:
* ACPI_STRTOUL_32BIT - Max integer value is 32 bits
* ACPI_STRTOUL_64BIT - Max integer value is 64 bits
* ACPI_STRTOUL_BASE16 - Input string is hexadecimal. Default
* is 10/16 based on string prefix (0x).
*
* NOTES:
* Negative numbers are not supported, as they are not supported by ACPI.
*
* Supports only base 16 or base 10 strings/values. Does not
* support Octal strings, as these are not supported by ACPI.
*
* Current users of this support:
*
* interpreter - Implicit and explicit conversions, GPE method names
* debugger - Command line input string conversion
* iASL - Main parser, conversion of constants to integers
* iASL - Data Table Compiler parser (constant math expressions)
* iASL - Preprocessor (constant math expressions)
* acpi_dump - Input table addresses
* acpi_exec - Testing of the acpi_ut_strtoul64 function
*
* Note concerning callers:
* acpi_gbl_integer_byte_width can be used to set the 32/64 limit. If used,
* this global should be set to the proper width. For the core ACPICA code,
* this width depends on the DSDT version. For iASL, the default byte
* width is always 8 for the parser, but error checking is performed later
* to flag cases where a 64-bit constant is defined in a 32-bit DSDT/SSDT.
*
******************************************************************************/
acpi_status acpi_ut_strtoul64(char *string, u32 flags, u64 *return_value)
{
acpi_status status = AE_OK;
u32 base;
ACPI_FUNCTION_TRACE_STR(ut_strtoul64, string);
/* Parameter validation */
if (!string || !return_value) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
*return_value = 0;
/* Check for zero-length string, returns 0 */
if (*string == 0) {
return_ACPI_STATUS(AE_OK);
}
/* Skip over any white space at start of string */
while (isspace((int)*string)) {
string++;
}
/* End of string? return 0 */
if (*string == 0) {
return_ACPI_STATUS(AE_OK);
}
/*
* 1) The "0x" prefix indicates base 16. Per the ACPI specification,
* the "0x" prefix is only allowed for implicit (non-strict) conversions.
* However, we always allow it for compatibility with older ACPICA.
*/
if ((*string == ACPI_ASCII_ZERO) &&
(tolower((int)*(string + 1)) == 'x')) {
string += 2; /* Go past the 0x */
if (*string == 0) {
return_ACPI_STATUS(AE_OK); /* Return value 0 */
}
base = 16;
}
/* 2) Force to base 16 (implicit conversion case) */
else if (flags & ACPI_STRTOUL_BASE16) {
base = 16;
}
/* 3) Default fallback is to Base 10 */
else {
base = 10;
}
/* Skip all leading zeros */
while (*string == ACPI_ASCII_ZERO) {
string++;
if (*string == 0) {
return_ACPI_STATUS(AE_OK); /* Return value 0 */
}
}
/* Perform the base 16 or 10 conversion */
if (base == 16) {
*return_value = acpi_ut_strtoul_base16(string, flags);
} else {
*return_value = acpi_ut_strtoul_base10(string, flags);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_strtoul_base10
*
* PARAMETERS: string - Null terminated input string
* flags - Conversion info
*
* RETURN: 64-bit converted integer
*
* DESCRIPTION: Performs a base 10 conversion of the input string to an
* integer value, either 32 or 64 bits.
* Note: String must be valid and non-null.
*
******************************************************************************/
static u64 acpi_ut_strtoul_base10(char *string, u32 flags)
{
int ascii_digit;
u64 next_value;
u64 return_value = 0;
/* Main loop: convert each ASCII byte in the input string */
while (*string) {
ascii_digit = *string;
if (!isdigit(ascii_digit)) {
/* Not ASCII 0-9, terminate */
goto exit;
}
/* Convert and insert (add) the decimal digit */
next_value =
(return_value * 10) + (ascii_digit - ACPI_ASCII_ZERO);
/* Check for overflow (32 or 64 bit) - return current converted value */
if (((flags & ACPI_STRTOUL_32BIT) && (next_value > ACPI_UINT32_MAX)) || (next_value < return_value)) { /* 64-bit overflow case */
goto exit;
}
return_value = next_value;
string++;
}
exit:
return (return_value);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_strtoul_base16
*
* PARAMETERS: string - Null terminated input string
* flags - conversion info
*
* RETURN: 64-bit converted integer
*
* DESCRIPTION: Performs a base 16 conversion of the input string to an
* integer value, either 32 or 64 bits.
* Note: String must be valid and non-null.
*
******************************************************************************/
static u64 acpi_ut_strtoul_base16(char *string, u32 flags)
{
int ascii_digit;
u32 valid_digits = 1;
u64 return_value = 0;
/* Main loop: convert each ASCII byte in the input string */
while (*string) {
/* Check for overflow (32 or 64 bit) - return current converted value */
if ((valid_digits > 16) ||
((valid_digits > 8) && (flags & ACPI_STRTOUL_32BIT))) {
goto exit;
}
ascii_digit = *string;
if (!isxdigit(ascii_digit)) {
/* Not Hex ASCII A-F, a-f, or 0-9, terminate */
goto exit;
}
/* Convert and insert the hex digit */
return_value =
(return_value << 4) |
acpi_ut_ascii_char_to_hex(ascii_digit);
string++;
valid_digits++;
}
exit:
return (return_value);
}
