// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 /******************************************************************************* * * Module Name: utstrtoul64 - String-to-integer conversion support for both * 64-bit and 32-bit integers * ******************************************************************************/ #include <acpi/acpi.h> #include "accommon.h" #define _COMPONENT … 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 * acpi_dump - ACPI table physical addresses * acpi_exec - Support for namespace overrides * * Notes concerning users of these interfaces: * * acpi_gbl_integer_byte_width 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 * acpi_ut_strtoul64 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 acpi_ut_strtoul64 * interface. According the ACPI specification, there is no ACPI runtime * support (explicit/implicit) for octal string conversions. * ******************************************************************************/ /******************************************************************************* * * FUNCTION: acpi_ut_strtoul64 * * PARAMETERS: string - Null terminated input string, * must be a valid pointer * return_value - 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 * acpi_dump - ACPI table physical addresses * acpi_exec - Support for namespace overrides * ******************************************************************************/ acpi_status acpi_ut_strtoul64(char *string, u64 *return_value) { … } /******************************************************************************* * * FUNCTION: acpi_ut_implicit_strtoul64 * * 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) * ******************************************************************************/ u64 acpi_ut_implicit_strtoul64(char *string) { … } /******************************************************************************* * * FUNCTION: acpi_ut_explicit_strtoul64 * * 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: * to_integer ("1000") Decimal * to_integer ("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 to_integer 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 to_integer operator, as per the ACPI specification * ******************************************************************************/ u64 acpi_ut_explicit_strtoul64(char *string) { … }
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