`12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788` ``````#include "tommath_private.h" #ifdef BN_MP_READ_RADIX_C /* LibTomMath, multiple-precision integer library -- Tom St Denis * * LibTomMath is a library that provides multiple-precision * integer arithmetic as well as number theoretic functionality. * * The library was designed directly after the MPI library by * Michael Fromberger but has been written from scratch with * additional optimizations in place. * * SPDX-License-Identifier: Unlicense */ /* read a string [ASCII] in a given radix */ int mp_read_radix(mp_int *a, const char *str, int radix) { int y, res, neg; unsigned pos; char ch; /* zero the digit bignum */ mp_zero(a); /* make sure the radix is ok */ if ((radix < 2) || (radix > 64)) { return MP_VAL; } /* if the leading digit is a * minus set the sign to negative. */ if (*str == '-') { ++str; neg = MP_NEG; } else { neg = MP_ZPOS; } /* set the integer to the default of zero */ mp_zero(a); /* process each digit of the string */ while (*str != '\0') { /* if the radix <= 36 the conversion is case insensitive * this allows numbers like 1AB and 1ab to represent the same value * [e.g. in hex] */ ch = (radix <= 36) ? (char)toupper((int)*str) : *str; pos = (unsigned)(ch - '('); if (mp_s_rmap_reverse_sz < pos) { break; } y = (int)mp_s_rmap_reverse[pos]; /* if the char was found in the map * and is less than the given radix add it * to the number, otherwise exit the loop. */ if ((y == 0xff) || (y >= radix)) { break; } if ((res = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) { return res; } if ((res = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) { return res; } ++str; } /* if an illegal character was found, fail. */ if (!((*str == '\0') || (*str == '\r') || (*str == '\n'))) { mp_zero(a); return MP_VAL; } /* set the sign only if a != 0 */ if (mp_iszero(a) != MP_YES) { a->sign = neg; } return MP_OKAY; } #endif /* ref: HEAD -> master, tag: v1.1.0 */ /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */ /* commit time: 2019-01-28 20:32:32 +0100 */ ``````