`12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667` ``````#include #ifdef BN_MP_FREAD_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. * * The library is free for all purposes without any express * guarantee it works. * * Tom St Denis, tomstdenis@gmail.com, http://libtom.org */ /* read a bigint from a file stream in ASCII */ int mp_fread(mp_int *a, int radix, FILE *stream) { int err, ch, neg, y; /* clear a */ mp_zero(a); /* if first digit is - then set negative */ ch = fgetc(stream); if (ch == '-') { neg = MP_NEG; ch = fgetc(stream); } else { neg = MP_ZPOS; } for (;;) { /* find y in the radix map */ for (y = 0; y < radix; y++) { if (mp_s_rmap[y] == ch) { break; } } if (y == radix) { break; } /* shift up and add */ if ((err = mp_mul_d(a, radix, a)) != MP_OKAY) { return err; } if ((err = mp_add_d(a, y, a)) != MP_OKAY) { return err; } ch = fgetc(stream); } if (mp_cmp_d(a, 0) != MP_EQ) { a->sign = neg; } return MP_OKAY; } #endif /* \$Source\$ */ /* \$Revision: 0.41 \$ */ /* \$Date: 2007-04-18 09:58:18 +0000 \$ */ ``````