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Diffstat (limited to 'libtommath/bn_mp_init_size.c')
-rw-r--r-- | libtommath/bn_mp_init_size.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/libtommath/bn_mp_init_size.c b/libtommath/bn_mp_init_size.c new file mode 100644 index 0000000..8ed2c2a --- /dev/null +++ b/libtommath/bn_mp_init_size.c @@ -0,0 +1,44 @@ +#include <tommath.h> +#ifdef BN_MP_INIT_SIZE_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://math.libtomcrypt.com + */ + +/* init an mp_init for a given size */ +int mp_init_size (mp_int * a, int size) +{ + int x; + + /* pad size so there are always extra digits */ + size += (MP_PREC * 2) - (size % MP_PREC); + + /* alloc mem */ + a->dp = OPT_CAST(mp_digit) XMALLOC (sizeof (mp_digit) * size); + if (a->dp == NULL) { + return MP_MEM; + } + + /* set the members */ + a->used = 0; + a->alloc = size; + a->sign = MP_ZPOS; + + /* zero the digits */ + for (x = 0; x < size; x++) { + a->dp[x] = 0; + } + + return MP_OKAY; +} +#endif |