blob: 6ce6364957842b6524b27af14564ea914d556c58 [file] [log] [blame]
/*******************************************************************************
*
* Module Name: utstrtoul64 - String-to-integer conversion support for both
* 64-bit and 32-bit integers
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2020, 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.
*
* 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 ("utstrtoul64")
/*******************************************************************************
*
* This module contains the top-level string to 64/32-bit unsigned integer
* conversion functions:
*
* 1) A standard strtoul() function that supports 64-bit integers, base
* 8/10/16, with integer overflow support. This is used mainly by the
* iASL compiler, which implements tighter constraints on integer
* constants than the runtime (interpreter) integer-to-string conversions.
* 2) Runtime "Explicit conversion" as defined in the ACPI specification.
* 3) Runtime "Implicit conversion" as defined in the ACPI specification.
*
* Current users of this module:
*
* iASL - Preprocessor (constants and math expressions)
* iASL - Main parser, conversion of constants to integers
* iASL - Data Table Compiler parser (constants and math expressions)
* Interpreter - Implicit and explicit conversions, GPE method names
* Interpreter - Repair code for return values from predefined names
* Debugger - Command line input string conversion
* AcpiDump - ACPI table physical addresses
* AcpiExec - Support for namespace overrides
*
* Notes concerning users of these interfaces:
*
* AcpiGbl_IntegerByteWidth is used to set the 32/64 bit limit for explicit
* and implicit conversions. This global must be set to the proper width.
* For the core ACPICA code, the width depends on the DSDT version. For the
* AcpiUtStrtoul64 interface, all conversions are 64 bits. This interface is
* used primarily for iASL, where the default width is 64 bits for all parsers,
* but error checking is performed later to flag cases where a 64-bit constant
* is wrongly defined in a 32-bit DSDT/SSDT.
*
* In ACPI, the only place where octal numbers are supported is within
* the ASL language itself. This is implemented via the main AcpiUtStrtoul64
* interface. According the ACPI specification, there is no ACPI runtime
* support (explicit/implicit) for octal string conversions.
*
******************************************************************************/
/*******************************************************************************
*
* FUNCTION: AcpiUtStrtoul64
*
* PARAMETERS: String - Null terminated input string,
* must be a valid pointer
* ReturnValue - Where the converted integer is
* returned. Must be a valid pointer
*
* RETURN: Status and converted integer. Returns an exception on a
* 64-bit numeric overflow
*
* DESCRIPTION: Convert a string into an unsigned integer. Always performs a
* full 64-bit conversion, regardless of the current global
* integer width. Supports Decimal, Hex, and Octal strings.
*
* Current users of this function:
*
* iASL - Preprocessor (constants and math expressions)
* iASL - Main ASL parser, conversion of ASL constants to integers
* iASL - Data Table Compiler parser (constants and math expressions)
* Interpreter - Repair code for return values from predefined names
* AcpiDump - ACPI table physical addresses
* AcpiExec - Support for namespace overrides
*
******************************************************************************/
ACPI_STATUS
AcpiUtStrtoul64 (
char *String,
UINT64 *ReturnValue)
{
ACPI_STATUS Status = AE_OK;
UINT8 OriginalBitWidth;
UINT32 Base = 10; /* Default is decimal */
ACPI_FUNCTION_TRACE_STR (UtStrtoul64, String);
*ReturnValue = 0;
/* A NULL return string returns a value of zero */
if (*String == 0)
{
return_ACPI_STATUS (AE_OK);
}
if (!AcpiUtRemoveWhitespace (&String))
{
return_ACPI_STATUS (AE_OK);
}
/*
* 1) Check for a hex constant. A "0x" prefix indicates base 16.
*/
if (AcpiUtDetectHexPrefix (&String))
{
Base = 16;
}
/*
* 2) Check for an octal constant, defined to be a leading zero
* followed by sequence of octal digits (0-7)
*/
else if (AcpiUtDetectOctalPrefix (&String))
{
Base = 8;
}
if (!AcpiUtRemoveLeadingZeros (&String))
{
return_ACPI_STATUS (AE_OK); /* Return value 0 */
}
/*
* Force a full 64-bit conversion. The caller (usually iASL) must
* check for a 32-bit overflow later as necessary (If current mode
* is 32-bit, meaning a 32-bit DSDT).
*/
OriginalBitWidth = AcpiGbl_IntegerBitWidth;
AcpiGbl_IntegerBitWidth = 64;
/*
* Perform the base 8, 10, or 16 conversion. A 64-bit numeric overflow
* will return an exception (to allow iASL to flag the statement).
*/
switch (Base)
{
case 8:
Status = AcpiUtConvertOctalString (String, ReturnValue);
break;
case 10:
Status = AcpiUtConvertDecimalString (String, ReturnValue);
break;
case 16:
default:
Status = AcpiUtConvertHexString (String, ReturnValue);
break;
}
/* Only possible exception from above is a 64-bit overflow */
AcpiGbl_IntegerBitWidth = OriginalBitWidth;
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtImplicitStrtoul64
*
* PARAMETERS: String - Null terminated input string,
* must be a valid pointer
*
* RETURN: Converted integer
*
* DESCRIPTION: Perform a 64-bit conversion with restrictions placed upon
* an "implicit conversion" by the ACPI specification. Used by
* many ASL operators that require an integer operand, and support
* an automatic (implicit) conversion from a string operand
* to the final integer operand. The major restriction is that
* only hex strings are supported.
*
* -----------------------------------------------------------------------------
*
* Base is always 16, either with or without the 0x prefix. Decimal and
* Octal strings are not supported, as per the ACPI specification.
*
* Examples (both are hex values):
* Add ("BA98", Arg0, Local0)
* Subtract ("0x12345678", Arg1, Local1)
*
* Conversion rules as extracted from the ACPI specification:
*
* The converted integer is initialized to the value zero.
* The ASCII string is always interpreted as a hexadecimal constant.
*
* 1) According to the ACPI specification, a "0x" prefix is not allowed.
* However, ACPICA allows this as an ACPI extension on general
* principle. (NO ERROR)
*
* 2) The conversion terminates when the size of an integer is reached
* (32 or 64 bits). There are no numeric overflow conditions. (NO ERROR)
*
* 3) The first non-hex character terminates the conversion and returns
* the current accumulated value of the converted integer (NO ERROR).
*
* 4) Conversion of a null (zero-length) string to an integer is
* technically not allowed. However, ACPICA allows this as an ACPI
* extension. The conversion returns the value 0. (NO ERROR)
*
* NOTE: There are no error conditions returned by this function. At
* the minimum, a value of zero is returned.
*
* Current users of this function:
*
* Interpreter - All runtime implicit conversions, as per ACPI specification
* iASL - Data Table Compiler parser (constants and math expressions)
*
******************************************************************************/
UINT64
AcpiUtImplicitStrtoul64 (
char *String)
{
UINT64 ConvertedInteger = 0;
ACPI_FUNCTION_TRACE_STR (UtImplicitStrtoul64, String);
if (!AcpiUtRemoveWhitespace (&String))
{
return_VALUE (0);
}
/*
* Per the ACPI specification, only hexadecimal is supported for
* implicit conversions, and the "0x" prefix is "not allowed".
* However, allow a "0x" prefix as an ACPI extension.
*/
AcpiUtRemoveHexPrefix (&String);
if (!AcpiUtRemoveLeadingZeros (&String))
{
return_VALUE (0);
}
/*
* Ignore overflow as per the ACPI specification. This is implemented by
* ignoring the return status from the conversion function called below.
* On overflow, the input string is simply truncated.
*/
AcpiUtConvertHexString (String, &ConvertedInteger);
return_VALUE (ConvertedInteger);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtExplicitStrtoul64
*
* PARAMETERS: String - Null terminated input string,
* must be a valid pointer
*
* RETURN: Converted integer
*
* DESCRIPTION: Perform a 64-bit conversion with the restrictions placed upon
* an "explicit conversion" by the ACPI specification. The
* main restriction is that only hex and decimal are supported.
*
* -----------------------------------------------------------------------------
*
* Base is either 10 (default) or 16 (with 0x prefix). Octal (base 8) strings
* are not supported, as per the ACPI specification.
*
* Examples:
* ToInteger ("1000") Decimal
* ToInteger ("0xABCD") Hex
*
* Conversion rules as extracted from the ACPI specification:
*
* 1) The input string is either a decimal or hexadecimal numeric string.
* A hex value must be prefixed by "0x" or it is interpreted as decimal.
*
* 2) The value must not exceed the maximum of an integer value
* (32 or 64 bits). The ACPI specification states the behavior is
* "unpredictable", so ACPICA matches the behavior of the implicit
* conversion case. There are no numeric overflow conditions. (NO ERROR)
*
* 3) Behavior on the first non-hex character is not defined by the ACPI
* specification (for the ToInteger operator), so ACPICA matches the
* behavior of the implicit conversion case. It terminates the
* conversion and returns the current accumulated value of the converted
* integer. (NO ERROR)
*
* 4) Conversion of a null (zero-length) string to an integer is
* technically not allowed. However, ACPICA allows this as an ACPI
* extension. The conversion returns the value 0. (NO ERROR)
*
* NOTE: There are no error conditions returned by this function. At the
* minimum, a value of zero is returned.
*
* Current users of this function:
*
* Interpreter - Runtime ASL ToInteger operator, as per the ACPI specification
*
******************************************************************************/
UINT64
AcpiUtExplicitStrtoul64 (
char *String)
{
UINT64 ConvertedInteger = 0;
UINT32 Base = 10; /* Default is decimal */
ACPI_FUNCTION_TRACE_STR (UtExplicitStrtoul64, String);
if (!AcpiUtRemoveWhitespace (&String))
{
return_VALUE (0);
}
/*
* Only Hex and Decimal are supported, as per the ACPI specification.
* A "0x" prefix indicates hex; otherwise decimal is assumed.
*/
if (AcpiUtDetectHexPrefix (&String))
{
Base = 16;
}
if (!AcpiUtRemoveLeadingZeros (&String))
{
return_VALUE (0);
}
/*
* Ignore overflow as per the ACPI specification. This is implemented by
* ignoring the return status from the conversion functions called below.
* On overflow, the input string is simply truncated.
*/
switch (Base)
{
case 10:
default:
AcpiUtConvertDecimalString (String, &ConvertedInteger);
break;
case 16:
AcpiUtConvertHexString (String, &ConvertedInteger);
break;
}
return_VALUE (ConvertedInteger);
}