/*******************************************************************************
*
* Module Name: utstrsuppt - Support functions for string-to-integer conversion
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2018, 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.h"
#include "accommon.h"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME ("utstrsuppt")
/* Local prototypes */
static ACPI_STATUS
AcpiUtInsertDigit (
UINT64 *AccumulatedValue,
UINT32 Base,
int AsciiDigit);
static ACPI_STATUS
AcpiUtStrtoulMultiply64 (
UINT64 Multiplicand,
UINT32 Base,
UINT64 *OutProduct);
static ACPI_STATUS
AcpiUtStrtoulAdd64 (
UINT64 Addend1,
UINT32 Digit,
UINT64 *OutSum);
/*******************************************************************************
*
* FUNCTION: AcpiUtConvertOctalString
*
* PARAMETERS: String - Null terminated input string
* ReturnValuePtr - Where the converted value is returned
*
* RETURN: Status and 64-bit converted integer
*
* DESCRIPTION: Performs a base 8 conversion of the input string to an
* integer value, either 32 or 64 bits.
*
* NOTE: Maximum 64-bit unsigned octal value is 01777777777777777777777
* Maximum 32-bit unsigned octal value is 037777777777
*
******************************************************************************/
ACPI_STATUS
AcpiUtConvertOctalString (
char *String,
UINT64 *ReturnValuePtr)
{
UINT64 AccumulatedValue = 0;
ACPI_STATUS Status = AE_OK;
/* Convert each ASCII byte in the input string */
while (*String)
{
/* Character must be ASCII 0-7, otherwise terminate with no error */
if (!(ACPI_IS_OCTAL_DIGIT (*String)))
{
break;
}
/* Convert and insert this octal digit into the accumulator */
Status = AcpiUtInsertDigit (&AccumulatedValue, 8, *String);
if (ACPI_FAILURE (Status))
{
Status = AE_OCTAL_OVERFLOW;
break;
}
String++;
}
/* Always return the value that has been accumulated */
*ReturnValuePtr = AccumulatedValue;
return (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtConvertDecimalString
*
* PARAMETERS: String - Null terminated input string
* ReturnValuePtr - Where the converted value is returned
*
* RETURN: Status and 64-bit converted integer
*
* DESCRIPTION: Performs a base 10 conversion of the input string to an
* integer value, either 32 or 64 bits.
*
* NOTE: Maximum 64-bit unsigned decimal value is 18446744073709551615
* Maximum 32-bit unsigned decimal value is 4294967295
*
******************************************************************************/
ACPI_STATUS
AcpiUtConvertDecimalString (
char *String,
UINT64 *ReturnValuePtr)
{
UINT64 AccumulatedValue = 0;
ACPI_STATUS Status = AE_OK;
/* Convert each ASCII byte in the input string */
while (*String)
{
/* Character must be ASCII 0-9, otherwise terminate with no error */
if (!isdigit (*String))
{
break;
}
/* Convert and insert this decimal digit into the accumulator */
Status = AcpiUtInsertDigit (&AccumulatedValue, 10, *String);
if (ACPI_FAILURE (Status))
{
Status = AE_DECIMAL_OVERFLOW;
break;
}
String++;
}
/* Always return the value that has been accumulated */
*ReturnValuePtr = AccumulatedValue;
return (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtConvertHexString
*
* PARAMETERS: String - Null terminated input string
* ReturnValuePtr - Where the converted value is returned
*
* RETURN: Status and 64-bit converted integer
*
* DESCRIPTION: Performs a base 16 conversion of the input string to an
* integer value, either 32 or 64 bits.
*
* NOTE: Maximum 64-bit unsigned hex value is 0xFFFFFFFFFFFFFFFF
* Maximum 32-bit unsigned hex value is 0xFFFFFFFF
*
******************************************************************************/
ACPI_STATUS
AcpiUtConvertHexString (
char *String,
UINT64 *ReturnValuePtr)
{
UINT64 AccumulatedValue = 0;
ACPI_STATUS Status = AE_OK;
/* Convert each ASCII byte in the input string */
while (*String)
{
/* Must be ASCII A-F, a-f, or 0-9, otherwise terminate with no error */
if (!isxdigit (*String))
{
break;
}
/* Convert and insert this hex digit into the accumulator */
Status = AcpiUtInsertDigit (&AccumulatedValue, 16, *String);
if (ACPI_FAILURE (Status))
{
Status = AE_HEX_OVERFLOW;
break;
}
String++;
}
/* Always return the value that has been accumulated */
*ReturnValuePtr = AccumulatedValue;
return (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtRemoveLeadingZeros
*
* PARAMETERS: String - Pointer to input ASCII string
*
* RETURN: Next character after any leading zeros. This character may be
* used by the caller to detect end-of-string.
*
* DESCRIPTION: Remove any leading zeros in the input string. Return the
* next character after the final ASCII zero to enable the caller
* to check for the end of the string (NULL terminator).
*
******************************************************************************/
char
AcpiUtRemoveLeadingZeros (
char **String)
{
while (**String == ACPI_ASCII_ZERO)
{
*String += 1;
}
return (**String);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtRemoveWhitespace
*
* PARAMETERS: String - Pointer to input ASCII string
*
* RETURN: Next character after any whitespace. This character may be
* used by the caller to detect end-of-string.
*
* DESCRIPTION: Remove any leading whitespace in the input string. Return the
* next character after the final ASCII zero to enable the caller
* to check for the end of the string (NULL terminator).
*
******************************************************************************/
char
AcpiUtRemoveWhitespace (
char **String)
{
while (isspace ((UINT8) **String))
{
*String += 1;
}
return (**String);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtDetectHexPrefix
*
* PARAMETERS: String - Pointer to input ASCII string
*
* RETURN: TRUE if a "0x" prefix was found at the start of the string
*
* DESCRIPTION: Detect and remove a hex "0x" prefix
*
******************************************************************************/
BOOLEAN
AcpiUtDetectHexPrefix (
char **String)
{
if ((**String == ACPI_ASCII_ZERO) &&
(tolower ((int) *(*String + 1)) == 'x'))
{
*String += 2; /* Go past the leading 0x */
return (TRUE);
}
return (FALSE); /* Not a hex string */
}
/*******************************************************************************
*
* FUNCTION: AcpiUtDetectOctalPrefix
*
* PARAMETERS: String - Pointer to input ASCII string
*
* RETURN: True if an octal "0" prefix was found at the start of the
* string
*
* DESCRIPTION: Detect and remove an octal prefix (zero)
*
******************************************************************************/
BOOLEAN
AcpiUtDetectOctalPrefix (
char **String)
{
if (**String == ACPI_ASCII_ZERO)
{
*String += 1; /* Go past the leading 0 */
return (TRUE);
}
return (FALSE); /* Not an octal string */
}
/*******************************************************************************
*
* FUNCTION: AcpiUtInsertDigit
*
* PARAMETERS: AccumulatedValue - Current value of the integer value
* accumulator. The new value is
* returned here.
* Base - Radix, either 8/10/16
* AsciiDigit - ASCII single digit to be inserted
*
* RETURN: Status and result of the convert/insert operation. The only
* possible returned exception code is numeric overflow of
* either the multiply or add conversion operations.
*
* DESCRIPTION: Generic conversion and insertion function for all bases:
*
* 1) Multiply the current accumulated/converted value by the
* base in order to make room for the new character.
*
* 2) Convert the new character to binary and add it to the
* current accumulated value.
*
* Note: The only possible exception indicates an integer
* overflow (AE_NUMERIC_OVERFLOW)
*
******************************************************************************/
static ACPI_STATUS
AcpiUtInsertDigit (
UINT64 *AccumulatedValue,
UINT32 Base,
int AsciiDigit)
{
ACPI_STATUS Status;
UINT64 Product;
/* Make room in the accumulated value for the incoming digit */
Status = AcpiUtStrtoulMultiply64 (*AccumulatedValue, Base, &Product);
if (ACPI_FAILURE (Status))
{
return (Status);
}
/* Add in the new digit, and store the sum to the accumulated value */
Status = AcpiUtStrtoulAdd64 (Product, AcpiUtAsciiCharToHex (AsciiDigit),
AccumulatedValue);
return (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtStrtoulMultiply64
*
* PARAMETERS: Multiplicand - Current accumulated converted integer
* Base - Base/Radix
* OutProduct - Where the product is returned
*
* RETURN: Status and 64-bit product
*
* DESCRIPTION: Multiply two 64-bit values, with checking for 64-bit overflow as
* well as 32-bit overflow if necessary (if the current global
* integer width is 32).
*
******************************************************************************/
static ACPI_STATUS
AcpiUtStrtoulMultiply64 (
UINT64 Multiplicand,
UINT32 Base,
UINT64 *OutProduct)
{
UINT64 Product;
UINT64 Quotient;
/* Exit if either operand is zero */
*OutProduct = 0;
if (!Multiplicand || !Base)
{
return (AE_OK);
}
/*
* Check for 64-bit overflow before the actual multiplication.
*
* Notes: 64-bit division is often not supported on 32-bit platforms
* (it requires a library function), Therefore ACPICA has a local
* 64-bit divide function. Also, Multiplier is currently only used
* as the radix (8/10/16), to the 64/32 divide will always work.
*/
AcpiUtShortDivide (ACPI_UINT64_MAX, Base, &Quotient, NULL);
if (Multiplicand > Quotient)
{
return (AE_NUMERIC_OVERFLOW);
}
Product = Multiplicand * Base;
/* Check for 32-bit overflow if necessary */
if ((AcpiGbl_IntegerBitWidth == 32) && (Product > ACPI_UINT32_MAX))
{
return (AE_NUMERIC_OVERFLOW);
}
*OutProduct = Product;
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtStrtoulAdd64
*
* PARAMETERS: Addend1 - Current accumulated converted integer
* Digit - New hex value/char
* OutSum - Where sum is returned (Accumulator)
*
* RETURN: Status and 64-bit sum
*
* DESCRIPTION: Add two 64-bit values, with checking for 64-bit overflow as
* well as 32-bit overflow if necessary (if the current global
* integer width is 32).
*
******************************************************************************/
static ACPI_STATUS
AcpiUtStrtoulAdd64 (
UINT64 Addend1,
UINT32 Digit,
UINT64 *OutSum)
{
UINT64 Sum;
/* Check for 64-bit overflow before the actual addition */
if ((Addend1 > 0) && (Digit > (ACPI_UINT64_MAX - Addend1)))
{
return (AE_NUMERIC_OVERFLOW);
}
Sum = Addend1 + Digit;
/* Check for 32-bit overflow if necessary */
if ((AcpiGbl_IntegerBitWidth == 32) && (Sum > ACPI_UINT32_MAX))
{
return (AE_NUMERIC_OVERFLOW);
}
*OutSum = Sum;
return (AE_OK);
}