diff options
Diffstat (limited to 'drivers/acpi/acpica/utstrtoul64.c')
| -rw-r--r-- | drivers/acpi/acpica/utstrtoul64.c | 442 |
1 files changed, 229 insertions, 213 deletions
diff --git a/drivers/acpi/acpica/utstrtoul64.c b/drivers/acpi/acpica/utstrtoul64.c index 9633ee142855..e2067dcb9389 100644 --- a/drivers/acpi/acpica/utstrtoul64.c +++ b/drivers/acpi/acpica/utstrtoul64.c @@ -1,6 +1,7 @@ /******************************************************************************* * - * Module Name: utstrtoul64 - string to 64-bit integer support + * Module Name: utstrtoul64 - String-to-integer conversion support for both + * 64-bit and 32-bit integers * ******************************************************************************/ @@ -44,304 +45,319 @@ #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. + * This module contains the top-level string to 64/32-bit unsigned integer + * conversion functions: * - * 1) A "0x" prefix is not allowed. However, ACPICA allows this for - * compatibility with previous ACPICA. (NO ERROR) + * 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. * - * 2) Terminates when the size of an integer is reached (32 or 64 bits). - * (NO ERROR) + * Current users of this module: * - * 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. + * 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 * - * 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) + * Notes concerning users of these interfaces: * - * 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) + * 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. * - * 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) + * 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 - * flags - Conversion info, see below + * PARAMETERS: string - Null terminated input string, + * must be a valid pointer * return_value - Where the converted integer is - * returned - * - * RETURN: Status and Converted value + * returned. Must be a valid pointer * - * 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). + * RETURN: Status and converted integer. Returns an exception on a + * 64-bit numeric overflow * - * 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). + * 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. * - * NOTES: - * Negative numbers are not supported, as they are not supported by ACPI. + * Current users of this function: * - * 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. + * 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, u32 flags, u64 *return_value) +acpi_status acpi_ut_strtoul64(char *string, u64 *return_value) { acpi_status status = AE_OK; - u32 base; + u8 original_bit_width; + u32 base = 10; /* Default is decimal */ 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 */ + /* A NULL return string returns a value of zero */ 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) { + if (!acpi_ut_remove_whitespace(&string)) { 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. + * 1) Check for a hex constant. A "0x" prefix indicates base 16. */ - 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 */ - } - + if (acpi_ut_detect_hex_prefix(&string)) { base = 16; } - /* 2) Force to base 16 (implicit conversion case) */ - - else if (flags & ACPI_STRTOUL_BASE16) { - 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; } - /* 3) Default fallback is to Base 10 */ - - else { - base = 10; + if (!acpi_ut_remove_leading_zeros(&string)) { + return_ACPI_STATUS(AE_OK); /* Return value 0 */ } - /* Skip all leading zeros */ + /* + * 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; - while (*string == ACPI_ASCII_ZERO) { - string++; - if (*string == 0) { - return_ACPI_STATUS(AE_OK); /* Return value 0 */ - } + /* + * 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; } - /* 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); - } + /* 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_strtoul_base10 + * 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). * - * PARAMETERS: string - Null terminated input string - * flags - Conversion info + * 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) * - * RETURN: 64-bit converted integer + * NOTE: There are no error conditions returned by this function. At + * the minimum, a value of zero is returned. * - * 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. + * Current users of this function: + * + * interpreter - All runtime implicit conversions, as per ACPI specification + * iASL - Data Table Compiler parser (constants and math expressions) * ******************************************************************************/ -static u64 acpi_ut_strtoul_base10(char *string, u32 flags) +u64 acpi_ut_implicit_strtoul64(char *string) { - 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 */ + u64 converted_integer = 0; - acpi_ut_short_multiply(return_value, 10, &next_value); - next_value += (ascii_digit - ACPI_ASCII_ZERO); + ACPI_FUNCTION_TRACE_STR(ut_implicit_strtoul64, string); - /* Check for overflow (32 or 64 bit) - return current converted value */ + if (!acpi_ut_remove_whitespace(&string)) { + return_VALUE(0); + } - if (((flags & ACPI_STRTOUL_32BIT) && (next_value > ACPI_UINT32_MAX)) || (next_value < return_value)) { /* 64-bit overflow case */ - goto exit; - } + /* + * 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_detect_hex_prefix(&string); - return_value = next_value; - string++; + if (!acpi_ut_remove_leading_zeros(&string)) { + return_VALUE(0); } -exit: - return (return_value); + /* + * 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_strtoul_base16 + * FUNCTION: acpi_ut_explicit_strtoul64 + * + * PARAMETERS: string - Null terminated input string, + * must be a valid pointer * - * PARAMETERS: string - Null terminated input string - * flags - conversion info + * RETURN: Converted integer * - * RETURN: 64-bit 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. * - * 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. + * ----------------------------------------------------------------------------- + * + * 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 * ******************************************************************************/ -static u64 acpi_ut_strtoul_base16(char *string, u32 flags) +u64 acpi_ut_explicit_strtoul64(char *string) { - int ascii_digit; - u32 valid_digits = 1; - u64 return_value = 0; - - /* Main loop: convert each ASCII byte in the input string */ + u64 converted_integer = 0; + u32 base = 10; /* Default is decimal */ - while (*string) { + ACPI_FUNCTION_TRACE_STR(ut_explicit_strtoul64, 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; - } + if (!acpi_ut_remove_whitespace(&string)) { + return_VALUE(0); + } - /* Convert and insert the hex digit */ + /* + * 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; + } - acpi_ut_short_shift_left(return_value, 4, &return_value); - return_value |= acpi_ut_ascii_char_to_hex(ascii_digit); + if (!acpi_ut_remove_leading_zeros(&string)) { + return_VALUE(0); + } - string++; - valid_digits++; + /* + * 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; } -exit: - return (return_value); + return_VALUE(converted_integer); } |