72 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			72 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
#include <tommath_private.h>
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#ifdef BN_MP_FREAD_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis
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 *
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 * LibTomMath is a library that provides multiple-precision
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 * integer arithmetic as well as number theoretic functionality.
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 *
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 * The library was designed directly after the MPI library by
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 * Michael Fromberger but has been written from scratch with
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 * additional optimizations in place.
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 *
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 * The library is free for all purposes without any express
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 * guarantee it works.
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 *
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 * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
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 */
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#ifndef LTM_NO_FILE
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/* read a bigint from a file stream in ASCII */
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int mp_fread(mp_int *a, int radix, FILE *stream)
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{
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   int err, ch, neg, y;
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   unsigned pos;
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   /* clear a */
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   mp_zero(a);
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   /* if first digit is - then set negative */
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   ch = fgetc(stream);
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   if (ch == (int)'-') {
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      neg = MP_NEG;
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      ch = fgetc(stream);
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   } else {
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      neg = MP_ZPOS;
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   }
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   for (;;) {
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      pos = (unsigned)(ch - (int)'(');
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      if (mp_s_rmap_reverse_sz < pos) {
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         break;
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      }
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      y = (int)mp_s_rmap_reverse[pos];
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      if ((y == 0xff) || (y >= radix)) {
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         break;
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      }
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      /* shift up and add */
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      if ((err = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
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         return err;
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      }
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      if ((err = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
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         return err;
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      }
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      ch = fgetc(stream);
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   }
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   if (mp_cmp_d(a, 0uL) != MP_EQ) {
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      a->sign = neg;
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   }
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   return MP_OKAY;
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}
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#endif
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#endif
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/* ref:         $Format:%D$ */
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/* git commit:  $Format:%H$ */
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/* commit time: $Format:%ai$ */
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