diff options
Diffstat (limited to 'drivers/acpi/acpica/utstrtoul64.c')
| -rw-r--r-- | drivers/acpi/acpica/utstrtoul64.c | 348 |
1 files changed, 348 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/utstrtoul64.c b/drivers/acpi/acpica/utstrtoul64.c new file mode 100644 index 000000000000..b4f341c98a95 --- /dev/null +++ b/drivers/acpi/acpica/utstrtoul64.c @@ -0,0 +1,348 @@ +/******************************************************************************* + * + * Module Name: utstrtoul64 - string to 64-bit integer support + * + ******************************************************************************/ + +/* + * Copyright (C) 2000 - 2016, 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/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. + * + * 1) A "0x" prefix is not allowed. However, ACPICA allows this for + * compatibility with previous ACPICA. (NO ERROR) + * + * 2) Terminates when the size of an integer is reached (32 or 64 bits). + * (NO ERROR) + * + * 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. + * + * 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) + * + * 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) + * + * 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) + * + ******************************************************************************/ + +/******************************************************************************* + * + * FUNCTION: acpi_ut_strtoul64 + * + * PARAMETERS: string - Null terminated input string + * flags - Conversion info, see below + * return_value - Where the converted integer is + * returned + * + * RETURN: Status and Converted value + * + * 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). + * + * 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). + * + * NOTES: + * Negative numbers are not supported, as they are not supported by ACPI. + * + * 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. + * + ******************************************************************************/ + +acpi_status acpi_ut_strtoul64(char *string, u32 flags, u64 *return_value) +{ + acpi_status status = AE_OK; + u32 base; + + 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 */ + + 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) { + 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. + */ + 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 */ + } + + base = 16; + } + + /* 2) Force to base 16 (implicit conversion case) */ + + else if (flags & ACPI_STRTOUL_BASE16) { + base = 16; + } + + /* 3) Default fallback is to Base 10 */ + + else { + base = 10; + } + + /* Skip all leading zeros */ + + while (*string == ACPI_ASCII_ZERO) { + string++; + if (*string == 0) { + return_ACPI_STATUS(AE_OK); /* Return value 0 */ + } + } + + /* 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); + } + + return_ACPI_STATUS(status); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ut_strtoul_base10 + * + * PARAMETERS: string - Null terminated input string + * flags - Conversion info + * + * RETURN: 64-bit converted integer + * + * 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. + * + ******************************************************************************/ + +static u64 acpi_ut_strtoul_base10(char *string, u32 flags) +{ + 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 */ + + next_value = + (return_value * 10) + (ascii_digit - ACPI_ASCII_ZERO); + + /* Check for overflow (32 or 64 bit) - return current converted value */ + + if (((flags & ACPI_STRTOUL_32BIT) && (next_value > ACPI_UINT32_MAX)) || (next_value < return_value)) { /* 64-bit overflow case */ + goto exit; + } + + return_value = next_value; + string++; + } + +exit: + return (return_value); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ut_strtoul_base16 + * + * PARAMETERS: string - Null terminated input string + * flags - conversion info + * + * RETURN: 64-bit converted integer + * + * 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. + * + ******************************************************************************/ + +static u64 acpi_ut_strtoul_base16(char *string, u32 flags) +{ + int ascii_digit; + u32 valid_digits = 1; + u64 return_value = 0; + + /* Main loop: convert each ASCII byte in the input string */ + + while (*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; + } + + /* Convert and insert the hex digit */ + + return_value = + (return_value << 4) | + acpi_ut_ascii_char_to_hex(ascii_digit); + + string++; + valid_digits++; + } + +exit: + return (return_value); +} |