| // 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_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 |
| * 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) |
| { |
| acpi_status status = AE_OK; |
| u8 original_bit_width; |
| u32 base = 10; /* Default is decimal */ |
| |
| ACPI_FUNCTION_TRACE_STR(ut_strtoul64, string); |
| |
| *return_value = 0; |
| |
| /* A NULL return string returns a value of zero */ |
| |
| if (*string == 0) { |
| return_ACPI_STATUS(AE_OK); |
| } |
| |
| if (!acpi_ut_remove_whitespace(&string)) { |
| return_ACPI_STATUS(AE_OK); |
| } |
| |
| /* |
| * 1) Check for a hex constant. A "0x" prefix indicates base 16. |
| */ |
| if (acpi_ut_detect_hex_prefix(&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 (acpi_ut_detect_octal_prefix(&string)) { |
| base = 8; |
| } |
| |
| if (!acpi_ut_remove_leading_zeros(&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). |
| */ |
| original_bit_width = acpi_gbl_integer_bit_width; |
| acpi_gbl_integer_bit_width = 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 = acpi_ut_convert_octal_string(string, return_value); |
| break; |
| |
| case 10: |
| status = acpi_ut_convert_decimal_string(string, return_value); |
| break; |
| |
| case 16: |
| default: |
| status = acpi_ut_convert_hex_string(string, return_value); |
| break; |
| } |
| |
| /* Only possible exception from above is a 64-bit overflow */ |
| |
| acpi_gbl_integer_bit_width = original_bit_width; |
| return_ACPI_STATUS(status); |
| } |
| |
| /******************************************************************************* |
| * |
| * 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) |
| { |
| u64 converted_integer = 0; |
| |
| ACPI_FUNCTION_TRACE_STR(ut_implicit_strtoul64, string); |
| |
| if (!acpi_ut_remove_whitespace(&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. |
| */ |
| acpi_ut_remove_hex_prefix(&string); |
| |
| if (!acpi_ut_remove_leading_zeros(&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. |
| */ |
| acpi_ut_convert_hex_string(string, &converted_integer); |
| return_VALUE(converted_integer); |
| } |
| |
| /******************************************************************************* |
| * |
| * 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) |
| { |
| u64 converted_integer = 0; |
| u32 base = 10; /* Default is decimal */ |
| |
| ACPI_FUNCTION_TRACE_STR(ut_explicit_strtoul64, string); |
| |
| if (!acpi_ut_remove_whitespace(&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 (acpi_ut_detect_hex_prefix(&string)) { |
| base = 16; |
| } |
| |
| if (!acpi_ut_remove_leading_zeros(&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: |
| acpi_ut_convert_decimal_string(string, &converted_integer); |
| break; |
| |
| case 16: |
| acpi_ut_convert_hex_string(string, &converted_integer); |
| break; |
| } |
| |
| return_VALUE(converted_integer); |
| } |