diff options
Diffstat (limited to 'libtommath/bn_mp_mul_d.c')
-rw-r--r-- | libtommath/bn_mp_mul_d.c | 89 |
1 files changed, 46 insertions, 43 deletions
diff --git a/libtommath/bn_mp_mul_d.c b/libtommath/bn_mp_mul_d.c index ba45a0c..0f6d03e 100644 --- a/libtommath/bn_mp_mul_d.c +++ b/libtommath/bn_mp_mul_d.c @@ -1,4 +1,4 @@ -#include <tommath.h> +#include <tommath_private.h> #ifdef BN_MP_MUL_D_C /* LibTomMath, multiple-precision integer library -- Tom St Denis * @@ -12,64 +12,67 @@ * The library is free for all purposes without any express * guarantee it works. * - * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com + * Tom St Denis, tstdenis82@gmail.com, http://libtom.org */ /* multiply by a digit */ -int -mp_mul_d (mp_int * a, mp_digit b, mp_int * c) +int mp_mul_d(const mp_int *a, mp_digit b, mp_int *c) { - mp_digit u, *tmpa, *tmpc; - mp_word r; - int ix, res, olduse; + mp_digit u, *tmpa, *tmpc; + mp_word r; + int ix, res, olduse; - /* make sure c is big enough to hold a*b */ - if (c->alloc < a->used + 1) { - if ((res = mp_grow (c, a->used + 1)) != MP_OKAY) { - return res; - } - } + /* make sure c is big enough to hold a*b */ + if (c->alloc < (a->used + 1)) { + if ((res = mp_grow(c, a->used + 1)) != MP_OKAY) { + return res; + } + } - /* get the original destinations used count */ - olduse = c->used; + /* get the original destinations used count */ + olduse = c->used; - /* set the sign */ - c->sign = a->sign; + /* set the sign */ + c->sign = a->sign; - /* alias for a->dp [source] */ - tmpa = a->dp; + /* alias for a->dp [source] */ + tmpa = a->dp; - /* alias for c->dp [dest] */ - tmpc = c->dp; + /* alias for c->dp [dest] */ + tmpc = c->dp; - /* zero carry */ - u = 0; + /* zero carry */ + u = 0; - /* compute columns */ - for (ix = 0; ix < a->used; ix++) { - /* compute product and carry sum for this term */ - r = ((mp_word) u) + ((mp_word)*tmpa++) * ((mp_word)b); + /* compute columns */ + for (ix = 0; ix < a->used; ix++) { + /* compute product and carry sum for this term */ + r = (mp_word)u + ((mp_word)*tmpa++ * (mp_word)b); - /* mask off higher bits to get a single digit */ - *tmpc++ = (mp_digit) (r & ((mp_word) MP_MASK)); + /* mask off higher bits to get a single digit */ + *tmpc++ = (mp_digit)(r & ((mp_word)MP_MASK)); - /* send carry into next iteration */ - u = (mp_digit) (r >> ((mp_word) DIGIT_BIT)); - } + /* send carry into next iteration */ + u = (mp_digit)(r >> ((mp_word)DIGIT_BIT)); + } - /* store final carry [if any] and increment ix offset */ - *tmpc++ = u; - ++ix; + /* store final carry [if any] and increment ix offset */ + *tmpc++ = u; + ++ix; - /* now zero digits above the top */ - while (ix++ < olduse) { - *tmpc++ = 0; - } + /* now zero digits above the top */ + while (ix++ < olduse) { + *tmpc++ = 0; + } - /* set used count */ - c->used = a->used + 1; - mp_clamp(c); + /* set used count */ + c->used = a->used + 1; + mp_clamp(c); - return MP_OKAY; + return MP_OKAY; } #endif + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */ |