| // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 |
| /******************************************************************************* |
| * |
| * Module Name: utstrsuppt - Support functions for string-to-integer conversion |
| * |
| ******************************************************************************/ |
| |
| #include <acpi/acpi.h> |
| #include "accommon.h" |
| |
| #define _COMPONENT ACPI_UTILITIES |
| ACPI_MODULE_NAME("utstrsuppt") |
| |
| /* Local prototypes */ |
| static acpi_status |
| acpi_ut_insert_digit(u64 *accumulated_value, u32 base, int ascii_digit); |
| |
| static acpi_status |
| acpi_ut_strtoul_multiply64(u64 multiplicand, u32 base, u64 *out_product); |
| |
| static acpi_status acpi_ut_strtoul_add64(u64 addend1, u32 digit, u64 *out_sum); |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_convert_octal_string |
| * |
| * PARAMETERS: string - Null terminated input string |
| * return_value_ptr - Where the converted value is returned |
| * |
| * RETURN: Status and 64-bit converted integer |
| * |
| * DESCRIPTION: Performs a base 8 conversion of the input string to an |
| * integer value, either 32 or 64 bits. |
| * |
| * NOTE: Maximum 64-bit unsigned octal value is 01777777777777777777777 |
| * Maximum 32-bit unsigned octal value is 037777777777 |
| * |
| ******************************************************************************/ |
| |
| acpi_status acpi_ut_convert_octal_string(char *string, u64 *return_value_ptr) |
| { |
| u64 accumulated_value = 0; |
| acpi_status status = AE_OK; |
| |
| /* Convert each ASCII byte in the input string */ |
| |
| while (*string) { |
| |
| /* Character must be ASCII 0-7, otherwise terminate with no error */ |
| |
| if (!(ACPI_IS_OCTAL_DIGIT(*string))) { |
| break; |
| } |
| |
| /* Convert and insert this octal digit into the accumulator */ |
| |
| status = acpi_ut_insert_digit(&accumulated_value, 8, *string); |
| if (ACPI_FAILURE(status)) { |
| status = AE_OCTAL_OVERFLOW; |
| break; |
| } |
| |
| string++; |
| } |
| |
| /* Always return the value that has been accumulated */ |
| |
| *return_value_ptr = accumulated_value; |
| return (status); |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_convert_decimal_string |
| * |
| * PARAMETERS: string - Null terminated input string |
| * return_value_ptr - Where the converted value is returned |
| * |
| * RETURN: Status and 64-bit converted integer |
| * |
| * DESCRIPTION: Performs a base 10 conversion of the input string to an |
| * integer value, either 32 or 64 bits. |
| * |
| * NOTE: Maximum 64-bit unsigned decimal value is 18446744073709551615 |
| * Maximum 32-bit unsigned decimal value is 4294967295 |
| * |
| ******************************************************************************/ |
| |
| acpi_status acpi_ut_convert_decimal_string(char *string, u64 *return_value_ptr) |
| { |
| u64 accumulated_value = 0; |
| acpi_status status = AE_OK; |
| |
| /* Convert each ASCII byte in the input string */ |
| |
| while (*string) { |
| |
| /* Character must be ASCII 0-9, otherwise terminate with no error */ |
| |
| if (!isdigit(*string)) { |
| break; |
| } |
| |
| /* Convert and insert this decimal digit into the accumulator */ |
| |
| status = acpi_ut_insert_digit(&accumulated_value, 10, *string); |
| if (ACPI_FAILURE(status)) { |
| status = AE_DECIMAL_OVERFLOW; |
| break; |
| } |
| |
| string++; |
| } |
| |
| /* Always return the value that has been accumulated */ |
| |
| *return_value_ptr = accumulated_value; |
| return (status); |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_convert_hex_string |
| * |
| * PARAMETERS: string - Null terminated input string |
| * return_value_ptr - Where the converted value is returned |
| * |
| * RETURN: Status and 64-bit converted integer |
| * |
| * DESCRIPTION: Performs a base 16 conversion of the input string to an |
| * integer value, either 32 or 64 bits. |
| * |
| * NOTE: Maximum 64-bit unsigned hex value is 0xFFFFFFFFFFFFFFFF |
| * Maximum 32-bit unsigned hex value is 0xFFFFFFFF |
| * |
| ******************************************************************************/ |
| |
| acpi_status acpi_ut_convert_hex_string(char *string, u64 *return_value_ptr) |
| { |
| u64 accumulated_value = 0; |
| acpi_status status = AE_OK; |
| |
| /* Convert each ASCII byte in the input string */ |
| |
| while (*string) { |
| |
| /* Must be ASCII A-F, a-f, or 0-9, otherwise terminate with no error */ |
| |
| if (!isxdigit(*string)) { |
| break; |
| } |
| |
| /* Convert and insert this hex digit into the accumulator */ |
| |
| status = acpi_ut_insert_digit(&accumulated_value, 16, *string); |
| if (ACPI_FAILURE(status)) { |
| status = AE_HEX_OVERFLOW; |
| break; |
| } |
| |
| string++; |
| } |
| |
| /* Always return the value that has been accumulated */ |
| |
| *return_value_ptr = accumulated_value; |
| return (status); |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_remove_leading_zeros |
| * |
| * PARAMETERS: string - Pointer to input ASCII string |
| * |
| * RETURN: Next character after any leading zeros. This character may be |
| * used by the caller to detect end-of-string. |
| * |
| * DESCRIPTION: Remove any leading zeros in the input string. Return the |
| * next character after the final ASCII zero to enable the caller |
| * to check for the end of the string (NULL terminator). |
| * |
| ******************************************************************************/ |
| |
| char acpi_ut_remove_leading_zeros(char **string) |
| { |
| |
| while (**string == ACPI_ASCII_ZERO) { |
| *string += 1; |
| } |
| |
| return (**string); |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_remove_whitespace |
| * |
| * PARAMETERS: string - Pointer to input ASCII string |
| * |
| * RETURN: Next character after any whitespace. This character may be |
| * used by the caller to detect end-of-string. |
| * |
| * DESCRIPTION: Remove any leading whitespace in the input string. Return the |
| * next character after the final ASCII zero to enable the caller |
| * to check for the end of the string (NULL terminator). |
| * |
| ******************************************************************************/ |
| |
| char acpi_ut_remove_whitespace(char **string) |
| { |
| |
| while (isspace((u8)**string)) { |
| *string += 1; |
| } |
| |
| return (**string); |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_detect_hex_prefix |
| * |
| * PARAMETERS: string - Pointer to input ASCII string |
| * |
| * RETURN: TRUE if a "0x" prefix was found at the start of the string |
| * |
| * DESCRIPTION: Detect and remove a hex "0x" prefix |
| * |
| ******************************************************************************/ |
| |
| u8 acpi_ut_detect_hex_prefix(char **string) |
| { |
| char *initial_position = *string; |
| |
| acpi_ut_remove_hex_prefix(string); |
| if (*string != initial_position) { |
| return (TRUE); /* String is past leading 0x */ |
| } |
| |
| return (FALSE); /* Not a hex string */ |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_remove_hex_prefix |
| * |
| * PARAMETERS: string - Pointer to input ASCII string |
| * |
| * RETURN: none |
| * |
| * DESCRIPTION: Remove a hex "0x" prefix |
| * |
| ******************************************************************************/ |
| |
| void acpi_ut_remove_hex_prefix(char **string) |
| { |
| if ((**string == ACPI_ASCII_ZERO) && |
| (tolower((int)*(*string + 1)) == 'x')) { |
| *string += 2; /* Go past the leading 0x */ |
| } |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_detect_octal_prefix |
| * |
| * PARAMETERS: string - Pointer to input ASCII string |
| * |
| * RETURN: True if an octal "0" prefix was found at the start of the |
| * string |
| * |
| * DESCRIPTION: Detect and remove an octal prefix (zero) |
| * |
| ******************************************************************************/ |
| |
| u8 acpi_ut_detect_octal_prefix(char **string) |
| { |
| |
| if (**string == ACPI_ASCII_ZERO) { |
| *string += 1; /* Go past the leading 0 */ |
| return (TRUE); |
| } |
| |
| return (FALSE); /* Not an octal string */ |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_insert_digit |
| * |
| * PARAMETERS: accumulated_value - Current value of the integer value |
| * accumulator. The new value is |
| * returned here. |
| * base - Radix, either 8/10/16 |
| * ascii_digit - ASCII single digit to be inserted |
| * |
| * RETURN: Status and result of the convert/insert operation. The only |
| * possible returned exception code is numeric overflow of |
| * either the multiply or add conversion operations. |
| * |
| * DESCRIPTION: Generic conversion and insertion function for all bases: |
| * |
| * 1) Multiply the current accumulated/converted value by the |
| * base in order to make room for the new character. |
| * |
| * 2) Convert the new character to binary and add it to the |
| * current accumulated value. |
| * |
| * Note: The only possible exception indicates an integer |
| * overflow (AE_NUMERIC_OVERFLOW) |
| * |
| ******************************************************************************/ |
| |
| static acpi_status |
| acpi_ut_insert_digit(u64 *accumulated_value, u32 base, int ascii_digit) |
| { |
| acpi_status status; |
| u64 product; |
| |
| /* Make room in the accumulated value for the incoming digit */ |
| |
| status = acpi_ut_strtoul_multiply64(*accumulated_value, base, &product); |
| if (ACPI_FAILURE(status)) { |
| return (status); |
| } |
| |
| /* Add in the new digit, and store the sum to the accumulated value */ |
| |
| status = |
| acpi_ut_strtoul_add64(product, |
| acpi_ut_ascii_char_to_hex(ascii_digit), |
| accumulated_value); |
| |
| return (status); |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_strtoul_multiply64 |
| * |
| * PARAMETERS: multiplicand - Current accumulated converted integer |
| * base - Base/Radix |
| * out_product - Where the product is returned |
| * |
| * RETURN: Status and 64-bit product |
| * |
| * DESCRIPTION: Multiply two 64-bit values, with checking for 64-bit overflow as |
| * well as 32-bit overflow if necessary (if the current global |
| * integer width is 32). |
| * |
| ******************************************************************************/ |
| |
| static acpi_status |
| acpi_ut_strtoul_multiply64(u64 multiplicand, u32 base, u64 *out_product) |
| { |
| u64 product; |
| u64 quotient; |
| |
| /* Exit if either operand is zero */ |
| |
| *out_product = 0; |
| if (!multiplicand || !base) { |
| return (AE_OK); |
| } |
| |
| /* |
| * Check for 64-bit overflow before the actual multiplication. |
| * |
| * Notes: 64-bit division is often not supported on 32-bit platforms |
| * (it requires a library function), Therefore ACPICA has a local |
| * 64-bit divide function. Also, Multiplier is currently only used |
| * as the radix (8/10/16), to the 64/32 divide will always work. |
| */ |
| acpi_ut_short_divide(ACPI_UINT64_MAX, base, "ient, NULL); |
| if (multiplicand > quotient) { |
| return (AE_NUMERIC_OVERFLOW); |
| } |
| |
| product = multiplicand * base; |
| |
| /* Check for 32-bit overflow if necessary */ |
| |
| if ((acpi_gbl_integer_bit_width == 32) && (product > ACPI_UINT32_MAX)) { |
| return (AE_NUMERIC_OVERFLOW); |
| } |
| |
| *out_product = product; |
| return (AE_OK); |
| } |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: acpi_ut_strtoul_add64 |
| * |
| * PARAMETERS: addend1 - Current accumulated converted integer |
| * digit - New hex value/char |
| * out_sum - Where sum is returned (Accumulator) |
| * |
| * RETURN: Status and 64-bit sum |
| * |
| * DESCRIPTION: Add two 64-bit values, with checking for 64-bit overflow as |
| * well as 32-bit overflow if necessary (if the current global |
| * integer width is 32). |
| * |
| ******************************************************************************/ |
| |
| static acpi_status acpi_ut_strtoul_add64(u64 addend1, u32 digit, u64 *out_sum) |
| { |
| u64 sum; |
| |
| /* Check for 64-bit overflow before the actual addition */ |
| |
| if ((addend1 > 0) && (digit > (ACPI_UINT64_MAX - addend1))) { |
| return (AE_NUMERIC_OVERFLOW); |
| } |
| |
| sum = addend1 + digit; |
| |
| /* Check for 32-bit overflow if necessary */ |
| |
| if ((acpi_gbl_integer_bit_width == 32) && (sum > ACPI_UINT32_MAX)) { |
| return (AE_NUMERIC_OVERFLOW); |
| } |
| |
| *out_sum = sum; |
| return (AE_OK); |
| } |