diff tomsfastmath/src/bit/fp_rshd.c @ 643:a362b62d38b2 dropbear-tfm

Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a with Makefile.in renamed
author Matt Johnston <matt@ucc.asn.au>
date Wed, 23 Nov 2011 18:10:20 +0700
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tomsfastmath/src/bit/fp_rshd.c	Wed Nov 23 18:10:20 2011 +0700
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+/* TomsFastMath, a fast ISO C bignum library.
+ * 
+ * This project is meant to fill in where LibTomMath
+ * falls short.  That is speed ;-)
+ *
+ * This project is public domain and free for all purposes.
+ * 
+ * Tom St Denis, [email protected]
+ */
+#include <tfm.h>
+
+void fp_rshd(fp_int *a, int x)
+{
+  int y;
+
+  /* too many digits just zero and return */
+  if (x >= a->used) {
+     fp_zero(a);
+     return;
+  }
+
+   /* shift */
+   for (y = 0; y < a->used - x; y++) {
+      a->dp[y] = a->dp[y+x];
+   }
+
+   /* zero rest */
+   for (; y < a->used; y++) {
+      a->dp[y] = 0;
+   }
+   
+   /* decrement count */
+   a->used -= x;
+   fp_clamp(a);
+}
+
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */