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1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.02/*******************************************************************************3 *4 * Module Name: utstrsuppt - Support functions for string-to-integer conversion5 *6 ******************************************************************************/7 8#include <acpi/acpi.h>9#include "accommon.h"10 11#define _COMPONENT ACPI_UTILITIES12ACPI_MODULE_NAME("utstrsuppt")13 14/* Local prototypes */15static acpi_status16acpi_ut_insert_digit(u64 *accumulated_value, u32 base, int ascii_digit);17 18static acpi_status19acpi_ut_strtoul_multiply64(u64 multiplicand, u32 base, u64 *out_product);20 21static acpi_status acpi_ut_strtoul_add64(u64 addend1, u32 digit, u64 *out_sum);22 23/*******************************************************************************24 *25 * FUNCTION: acpi_ut_convert_octal_string26 *27 * PARAMETERS: string - Null terminated input string28 * return_value_ptr - Where the converted value is returned29 *30 * RETURN: Status and 64-bit converted integer31 *32 * DESCRIPTION: Performs a base 8 conversion of the input string to an33 * integer value, either 32 or 64 bits.34 *35 * NOTE: Maximum 64-bit unsigned octal value is 0177777777777777777777736 * Maximum 32-bit unsigned octal value is 03777777777737 *38 ******************************************************************************/39 40acpi_status acpi_ut_convert_octal_string(char *string, u64 *return_value_ptr)41{42 u64 accumulated_value = 0;43 acpi_status status = AE_OK;44 45 /* Convert each ASCII byte in the input string */46 47 while (*string) {48 /*49 * Character must be ASCII 0-7, otherwise:50 * 1) Runtime: terminate with no error, per the ACPI spec51 * 2) Compiler: return an error52 */53 if (!(ACPI_IS_OCTAL_DIGIT(*string))) {54#ifdef ACPI_ASL_COMPILER55 status = AE_BAD_OCTAL_CONSTANT;56#endif57 break;58 }59 60 /* Convert and insert this octal digit into the accumulator */61 62 status = acpi_ut_insert_digit(&accumulated_value, 8, *string);63 if (ACPI_FAILURE(status)) {64 status = AE_OCTAL_OVERFLOW;65 break;66 }67 68 string++;69 }70 71 /* Always return the value that has been accumulated */72 73 *return_value_ptr = accumulated_value;74 return (status);75}76 77/*******************************************************************************78 *79 * FUNCTION: acpi_ut_convert_decimal_string80 *81 * PARAMETERS: string - Null terminated input string82 * return_value_ptr - Where the converted value is returned83 *84 * RETURN: Status and 64-bit converted integer85 *86 * DESCRIPTION: Performs a base 10 conversion of the input string to an87 * integer value, either 32 or 64 bits.88 *89 * NOTE: Maximum 64-bit unsigned decimal value is 1844674407370955161590 * Maximum 32-bit unsigned decimal value is 429496729591 *92 ******************************************************************************/93 94acpi_status acpi_ut_convert_decimal_string(char *string, u64 *return_value_ptr)95{96 u64 accumulated_value = 0;97 acpi_status status = AE_OK;98 99 /* Convert each ASCII byte in the input string */100 101 while (*string) {102 /*103 * Character must be ASCII 0-9, otherwise:104 * 1) Runtime: terminate with no error, per the ACPI spec105 * 2) Compiler: return an error106 */107 if (!isdigit((int)*string)) {108#ifdef ACPI_ASL_COMPILER109 status = AE_BAD_DECIMAL_CONSTANT;110#endif111 break;112 }113 114 /* Convert and insert this decimal digit into the accumulator */115 116 status = acpi_ut_insert_digit(&accumulated_value, 10, *string);117 if (ACPI_FAILURE(status)) {118 status = AE_DECIMAL_OVERFLOW;119 break;120 }121 122 string++;123 }124 125 /* Always return the value that has been accumulated */126 127 *return_value_ptr = accumulated_value;128 return (status);129}130 131/*******************************************************************************132 *133 * FUNCTION: acpi_ut_convert_hex_string134 *135 * PARAMETERS: string - Null terminated input string136 * return_value_ptr - Where the converted value is returned137 *138 * RETURN: Status and 64-bit converted integer139 *140 * DESCRIPTION: Performs a base 16 conversion of the input string to an141 * integer value, either 32 or 64 bits.142 *143 * NOTE: Maximum 64-bit unsigned hex value is 0xFFFFFFFFFFFFFFFF144 * Maximum 32-bit unsigned hex value is 0xFFFFFFFF145 *146 ******************************************************************************/147 148acpi_status acpi_ut_convert_hex_string(char *string, u64 *return_value_ptr)149{150 u64 accumulated_value = 0;151 acpi_status status = AE_OK;152 153 /* Convert each ASCII byte in the input string */154 155 while (*string) {156 /*157 * Character must be ASCII A-F, a-f, or 0-9, otherwise:158 * 1) Runtime: terminate with no error, per the ACPI spec159 * 2) Compiler: return an error160 */161 if (!isxdigit((int)*string)) {162#ifdef ACPI_ASL_COMPILER163 status = AE_BAD_HEX_CONSTANT;164#endif165 break;166 }167 168 /* Convert and insert this hex digit into the accumulator */169 170 status = acpi_ut_insert_digit(&accumulated_value, 16, *string);171 if (ACPI_FAILURE(status)) {172 status = AE_HEX_OVERFLOW;173 break;174 }175 176 string++;177 }178 179 /* Always return the value that has been accumulated */180 181 *return_value_ptr = accumulated_value;182 return (status);183}184 185/*******************************************************************************186 *187 * FUNCTION: acpi_ut_remove_leading_zeros188 *189 * PARAMETERS: string - Pointer to input ASCII string190 *191 * RETURN: Next character after any leading zeros. This character may be192 * used by the caller to detect end-of-string.193 *194 * DESCRIPTION: Remove any leading zeros in the input string. Return the195 * next character after the final ASCII zero to enable the caller196 * to check for the end of the string (NULL terminator).197 *198 ******************************************************************************/199 200char acpi_ut_remove_leading_zeros(char **string)201{202 203 while (**string == ACPI_ASCII_ZERO) {204 *string += 1;205 }206 207 return (**string);208}209 210/*******************************************************************************211 *212 * FUNCTION: acpi_ut_remove_whitespace213 *214 * PARAMETERS: string - Pointer to input ASCII string215 *216 * RETURN: Next character after any whitespace. This character may be217 * used by the caller to detect end-of-string.218 *219 * DESCRIPTION: Remove any leading whitespace in the input string. Return the220 * next character after the final ASCII zero to enable the caller221 * to check for the end of the string (NULL terminator).222 *223 ******************************************************************************/224 225char acpi_ut_remove_whitespace(char **string)226{227 228 while (isspace((u8)**string)) {229 *string += 1;230 }231 232 return (**string);233}234 235/*******************************************************************************236 *237 * FUNCTION: acpi_ut_detect_hex_prefix238 *239 * PARAMETERS: string - Pointer to input ASCII string240 *241 * RETURN: TRUE if a "0x" prefix was found at the start of the string242 *243 * DESCRIPTION: Detect and remove a hex "0x" prefix244 *245 ******************************************************************************/246 247u8 acpi_ut_detect_hex_prefix(char **string)248{249 char *initial_position = *string;250 251 acpi_ut_remove_hex_prefix(string);252 if (*string != initial_position) {253 return (TRUE); /* String is past leading 0x */254 }255 256 return (FALSE); /* Not a hex string */257}258 259/*******************************************************************************260 *261 * FUNCTION: acpi_ut_remove_hex_prefix262 *263 * PARAMETERS: string - Pointer to input ASCII string264 *265 * RETURN: none266 *267 * DESCRIPTION: Remove a hex "0x" prefix268 *269 ******************************************************************************/270 271void acpi_ut_remove_hex_prefix(char **string)272{273 if ((**string == ACPI_ASCII_ZERO) &&274 (tolower((int)*(*string + 1)) == 'x')) {275 *string += 2; /* Go past the leading 0x */276 }277}278 279/*******************************************************************************280 *281 * FUNCTION: acpi_ut_detect_octal_prefix282 *283 * PARAMETERS: string - Pointer to input ASCII string284 *285 * RETURN: True if an octal "0" prefix was found at the start of the286 * string287 *288 * DESCRIPTION: Detect and remove an octal prefix (zero)289 *290 ******************************************************************************/291 292u8 acpi_ut_detect_octal_prefix(char **string)293{294 295 if (**string == ACPI_ASCII_ZERO) {296 *string += 1; /* Go past the leading 0 */297 return (TRUE);298 }299 300 return (FALSE); /* Not an octal string */301}302 303/*******************************************************************************304 *305 * FUNCTION: acpi_ut_insert_digit306 *307 * PARAMETERS: accumulated_value - Current value of the integer value308 * accumulator. The new value is309 * returned here.310 * base - Radix, either 8/10/16311 * ascii_digit - ASCII single digit to be inserted312 *313 * RETURN: Status and result of the convert/insert operation. The only314 * possible returned exception code is numeric overflow of315 * either the multiply or add conversion operations.316 *317 * DESCRIPTION: Generic conversion and insertion function for all bases:318 *319 * 1) Multiply the current accumulated/converted value by the320 * base in order to make room for the new character.321 *322 * 2) Convert the new character to binary and add it to the323 * current accumulated value.324 *325 * Note: The only possible exception indicates an integer326 * overflow (AE_NUMERIC_OVERFLOW)327 *328 ******************************************************************************/329 330static acpi_status331acpi_ut_insert_digit(u64 *accumulated_value, u32 base, int ascii_digit)332{333 acpi_status status;334 u64 product;335 336 /* Make room in the accumulated value for the incoming digit */337 338 status = acpi_ut_strtoul_multiply64(*accumulated_value, base, &product);339 if (ACPI_FAILURE(status)) {340 return (status);341 }342 343 /* Add in the new digit, and store the sum to the accumulated value */344 345 status =346 acpi_ut_strtoul_add64(product,347 acpi_ut_ascii_char_to_hex(ascii_digit),348 accumulated_value);349 350 return (status);351}352 353/*******************************************************************************354 *355 * FUNCTION: acpi_ut_strtoul_multiply64356 *357 * PARAMETERS: multiplicand - Current accumulated converted integer358 * base - Base/Radix359 * out_product - Where the product is returned360 *361 * RETURN: Status and 64-bit product362 *363 * DESCRIPTION: Multiply two 64-bit values, with checking for 64-bit overflow as364 * well as 32-bit overflow if necessary (if the current global365 * integer width is 32).366 *367 ******************************************************************************/368 369static acpi_status370acpi_ut_strtoul_multiply64(u64 multiplicand, u32 base, u64 *out_product)371{372 u64 product;373 u64 quotient;374 375 /* Exit if either operand is zero */376 377 *out_product = 0;378 if (!multiplicand || !base) {379 return (AE_OK);380 }381 382 /*383 * Check for 64-bit overflow before the actual multiplication.384 *385 * Notes: 64-bit division is often not supported on 32-bit platforms386 * (it requires a library function), Therefore ACPICA has a local387 * 64-bit divide function. Also, Multiplier is currently only used388 * as the radix (8/10/16), to the 64/32 divide will always work.389 */390 acpi_ut_short_divide(ACPI_UINT64_MAX, base, "ient, NULL);391 if (multiplicand > quotient) {392 return (AE_NUMERIC_OVERFLOW);393 }394 395 product = multiplicand * base;396 397 /* Check for 32-bit overflow if necessary */398 399 if ((acpi_gbl_integer_bit_width == 32) && (product > ACPI_UINT32_MAX)) {400 return (AE_NUMERIC_OVERFLOW);401 }402 403 *out_product = product;404 return (AE_OK);405}406 407/*******************************************************************************408 *409 * FUNCTION: acpi_ut_strtoul_add64410 *411 * PARAMETERS: addend1 - Current accumulated converted integer412 * digit - New hex value/char413 * out_sum - Where sum is returned (Accumulator)414 *415 * RETURN: Status and 64-bit sum416 *417 * DESCRIPTION: Add two 64-bit values, with checking for 64-bit overflow as418 * well as 32-bit overflow if necessary (if the current global419 * integer width is 32).420 *421 ******************************************************************************/422 423static acpi_status acpi_ut_strtoul_add64(u64 addend1, u32 digit, u64 *out_sum)424{425 u64 sum;426 427 /* Check for 64-bit overflow before the actual addition */428 429 if ((addend1 > 0) && (digit > (ACPI_UINT64_MAX - addend1))) {430 return (AE_NUMERIC_OVERFLOW);431 }432 433 sum = addend1 + digit;434 435 /* Check for 32-bit overflow if necessary */436 437 if ((acpi_gbl_integer_bit_width == 32) && (sum > ACPI_UINT32_MAX)) {438 return (AE_NUMERIC_OVERFLOW);439 }440 441 *out_sum = sum;442 return (AE_OK);443}444