39 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			39 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "tommath_private.h"
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| #ifdef BN_MP_GROW_C
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| /* LibTomMath, multiple-precision integer library -- Tom St Denis */
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| /* SPDX-License-Identifier: Unlicense */
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| 
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| /* grow as required */
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| mp_err mp_grow(mp_int *a, int size)
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| {
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|    int     i;
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|    mp_digit *tmp;
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| 
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|    /* if the alloc size is smaller alloc more ram */
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|    if (a->alloc < size) {
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|       /* reallocate the array a->dp
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|        *
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|        * We store the return in a temporary variable
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|        * in case the operation failed we don't want
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|        * to overwrite the dp member of a.
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|        */
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|       tmp = (mp_digit *) MP_REALLOC(a->dp,
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|                                     (size_t)a->alloc * sizeof(mp_digit),
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|                                     (size_t)size * sizeof(mp_digit));
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|       if (tmp == NULL) {
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|          /* reallocation failed but "a" is still valid [can be freed] */
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|          return MP_MEM;
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|       }
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| 
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|       /* reallocation succeeded so set a->dp */
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|       a->dp = tmp;
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| 
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|       /* zero excess digits */
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|       i        = a->alloc;
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|       a->alloc = size;
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|       MP_ZERO_DIGITS(a->dp + i, a->alloc - i);
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|    }
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|    return MP_OKAY;
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| }
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| #endif
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