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authorSteffen Jaeckel <s@jaeckel.eu>2020-05-26 17:36:47 +0200
committerSteffen Jaeckel <s@jaeckel.eu>2020-05-26 17:36:47 +0200
commit4f11c927dfb74496017fd1d2e2b18e3afb2a93fd (patch)
treeb448865b4989998f041b159bd913b79542f8623a /libtommath/bn_mp_decr.c
parent1de4c3c6588830f9c2c4c7236596f5e0c639e588 (diff)
downloaddropbear-4f11c927dfb74496017fd1d2e2b18e3afb2a93fd.tar.gz
Update LibTomMath to 1.2.0 (#84)
* update C files * update other files * update headers * update makefiles * remove mp_set/get_double() * use ltm 1.2.0 API * update ltm_desc * use bundled tommath if system-tommath is too old * XMALLOC etc. were changed to MP_MALLOC etc.
Diffstat (limited to 'libtommath/bn_mp_decr.c')
-rw-r--r--libtommath/bn_mp_decr.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/libtommath/bn_mp_decr.c b/libtommath/bn_mp_decr.c
new file mode 100644
index 0000000..c6a1572
--- /dev/null
+++ b/libtommath/bn_mp_decr.c
@@ -0,0 +1,34 @@
+#include "tommath_private.h"
+#ifdef BN_MP_DECR_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+
+/* Decrement "a" by one like "a--". Changes input! */
+mp_err mp_decr(mp_int *a)
+{
+ if (MP_IS_ZERO(a)) {
+ mp_set(a,1uL);
+ a->sign = MP_NEG;
+ return MP_OKAY;
+ } else if (a->sign == MP_NEG) {
+ mp_err err;
+ a->sign = MP_ZPOS;
+ if ((err = mp_incr(a)) != MP_OKAY) {
+ return err;
+ }
+ /* There is no -0 in LTM */
+ if (!MP_IS_ZERO(a)) {
+ a->sign = MP_NEG;
+ }
+ return MP_OKAY;
+ } else if (a->dp[0] > 1uL) {
+ a->dp[0]--;
+ if (a->dp[0] == 0u) {
+ mp_zero(a);
+ }
+ return MP_OKAY;
+ } else {
+ return mp_sub_d(a, 1uL,a);
+ }
+}
+#endif