summaryrefslogtreecommitdiffstats
path: root/libtommath/bn_s_mp_sub.c
diff options
context:
space:
mode:
authorNikos Mavrogiannopoulos <nmav@gnutls.org>2010-09-06 17:20:33 +0200
committerNikos Mavrogiannopoulos <nmav@gnutls.org>2010-09-06 17:26:58 +0200
commite6177630198eb1eea2def0374fae1196da0e40ec (patch)
tree704951804609999fb6ef7a956b04921b9f84c320 /libtommath/bn_s_mp_sub.c
parent943f9ab50c110133a5cd1118b5b19cb09301168f (diff)
downloadcryptodev-linux-e6177630198eb1eea2def0374fae1196da0e40ec.tar.gz
cryptodev-linux-e6177630198eb1eea2def0374fae1196da0e40ec.tar.xz
cryptodev-linux-e6177630198eb1eea2def0374fae1196da0e40ec.zip
Run Lindent on libtom(*)
Diffstat (limited to 'libtommath/bn_s_mp_sub.c')
-rw-r--r--libtommath/bn_s_mp_sub.c103
1 files changed, 52 insertions, 51 deletions
diff --git a/libtommath/bn_s_mp_sub.c b/libtommath/bn_s_mp_sub.c
index 6a60c39..d8e473f 100644
--- a/libtommath/bn_s_mp_sub.c
+++ b/libtommath/bn_s_mp_sub.c
@@ -16,70 +16,71 @@
*/
/* low level subtraction (assumes |a| > |b|), HAC pp.595 Algorithm 14.9 */
-int
-s_mp_sub (mp_int * a, mp_int * b, mp_int * c)
+int s_mp_sub(mp_int * a, mp_int * b, mp_int * c)
{
- int olduse, res, min, max;
+ int olduse, res, min, max;
- /* find sizes */
- min = b->used;
- max = a->used;
+ /* find sizes */
+ min = b->used;
+ max = a->used;
- /* init result */
- if (c->alloc < max) {
- if ((res = mp_grow (c, max)) != MP_OKAY) {
- return res;
- }
- }
- olduse = c->used;
- c->used = max;
+ /* init result */
+ if (c->alloc < max) {
+ if ((res = mp_grow(c, max)) != MP_OKAY) {
+ return res;
+ }
+ }
+ olduse = c->used;
+ c->used = max;
- {
- register mp_digit u, *tmpa, *tmpb, *tmpc;
- register int i;
+ {
+ register mp_digit u, *tmpa, *tmpb, *tmpc;
+ register int i;
- /* alias for digit pointers */
- tmpa = a->dp;
- tmpb = b->dp;
- tmpc = c->dp;
+ /* alias for digit pointers */
+ tmpa = a->dp;
+ tmpb = b->dp;
+ tmpc = c->dp;
- /* set carry to zero */
- u = 0;
- for (i = 0; i < min; i++) {
- /* T[i] = A[i] - B[i] - U */
- *tmpc = *tmpa++ - *tmpb++ - u;
+ /* set carry to zero */
+ u = 0;
+ for (i = 0; i < min; i++) {
+ /* T[i] = A[i] - B[i] - U */
+ *tmpc = *tmpa++ - *tmpb++ - u;
- /* U = carry bit of T[i]
- * Note this saves performing an AND operation since
- * if a carry does occur it will propagate all the way to the
- * MSB. As a result a single shift is enough to get the carry
- */
- u = *tmpc >> ((mp_digit)(CHAR_BIT * sizeof (mp_digit) - 1));
+ /* U = carry bit of T[i]
+ * Note this saves performing an AND operation since
+ * if a carry does occur it will propagate all the way to the
+ * MSB. As a result a single shift is enough to get the carry
+ */
+ u = *tmpc >>
+ ((mp_digit) (CHAR_BIT * sizeof(mp_digit) - 1));
- /* Clear carry from T[i] */
- *tmpc++ &= MP_MASK;
- }
+ /* Clear carry from T[i] */
+ *tmpc++ &= MP_MASK;
+ }
- /* now copy higher words if any, e.g. if A has more digits than B */
- for (; i < max; i++) {
- /* T[i] = A[i] - U */
- *tmpc = *tmpa++ - u;
+ /* now copy higher words if any, e.g. if A has more digits than B */
+ for (; i < max; i++) {
+ /* T[i] = A[i] - U */
+ *tmpc = *tmpa++ - u;
- /* U = carry bit of T[i] */
- u = *tmpc >> ((mp_digit)(CHAR_BIT * sizeof (mp_digit) - 1));
+ /* U = carry bit of T[i] */
+ u = *tmpc >>
+ ((mp_digit) (CHAR_BIT * sizeof(mp_digit) - 1));
- /* Clear carry from T[i] */
- *tmpc++ &= MP_MASK;
- }
+ /* Clear carry from T[i] */
+ *tmpc++ &= MP_MASK;
+ }
- /* clear digits above used (since we may not have grown result above) */
- for (i = c->used; i < olduse; i++) {
- *tmpc++ = 0;
- }
- }
+ /* clear digits above used (since we may not have grown result above) */
+ for (i = c->used; i < olduse; i++) {
+ *tmpc++ = 0;
+ }
+ }
- mp_clamp (c);
- return MP_OKAY;
+ mp_clamp(c);
+ return MP_OKAY;
}
#endif