Mercurial > dropbear
view libtommath/bn_mp_lcm.c @ 1088:f2a3570b5110
Test struct existance against sizeof() operator
Instead of declaring an "unused-variable" or "unused-but-set-variable"
structure.
This avoid unexpected broken configurations when using something like:
$ ./configure CFLAGS="-Wall -Wextra -Werror"
It causes AC_COMPILE_IFELSE to fail and thus leading to a mismatch
configuration (because the CFLAGS are passed to the macro).
author | Gaël PORTAY <gael.portay@gmail.com> |
---|---|
date | Sat, 02 May 2015 13:33:34 +0200 |
parents | 5ff8218bcee9 |
children | 60fc6476e044 |
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#include <tommath.h> #ifdef BN_MP_LCM_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, [email protected], http://math.libtomcrypt.com */ /* computes least common multiple as |a*b|/(a, b) */ int mp_lcm (mp_int * a, mp_int * b, mp_int * c) { int res; mp_int t1, t2; if ((res = mp_init_multi (&t1, &t2, NULL)) != MP_OKAY) { return res; } /* t1 = get the GCD of the two inputs */ if ((res = mp_gcd (a, b, &t1)) != MP_OKAY) { goto LBL_T; } /* divide the smallest by the GCD */ if (mp_cmp_mag(a, b) == MP_LT) { /* store quotient in t2 such that t2 * b is the LCM */ if ((res = mp_div(a, &t1, &t2, NULL)) != MP_OKAY) { goto LBL_T; } res = mp_mul(b, &t2, c); } else { /* store quotient in t2 such that t2 * a is the LCM */ if ((res = mp_div(b, &t1, &t2, NULL)) != MP_OKAY) { goto LBL_T; } res = mp_mul(a, &t2, c); } /* fix the sign to positive */ c->sign = MP_ZPOS; LBL_T: mp_clear_multi (&t1, &t2, NULL); return res; } #endif /* $Source: /cvs/libtom/libtommath/bn_mp_lcm.c,v $ */ /* $Revision: 1.3 $ */ /* $Date: 2006/03/31 14:18:44 $ */