44 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			44 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <tommath_private.h>
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| #ifdef BN_MP_GET_INT_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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| 
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| /* get the lower 32-bits of an mp_int */
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| unsigned long mp_get_int(const mp_int *a)
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| {
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|    int i;
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|    mp_min_u32 res;
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| 
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|    if (a->used == 0) {
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|       return 0;
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|    }
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| 
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|    /* get number of digits of the lsb we have to read */
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|    i = MIN(a->used, ((((int)sizeof(unsigned long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
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| 
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|    /* get most significant digit of result */
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|    res = DIGIT(a, i);
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| 
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|    while (--i >= 0) {
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|       res = (res << DIGIT_BIT) | DIGIT(a, i);
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|    }
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| 
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|    /* force result to 32-bits always so it is consistent on non 32-bit platforms */
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|    return res & 0xFFFFFFFFUL;
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| }
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| #endif
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| 
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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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