Diff: math/bin/fp_radix_size.c

Revision:

0:35aa5be3b78d

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/math/bin/fp_radix_size.c	Fri Jun 06 10:49:02 2014 +0000
@@ -0,0 +1,53 @@
+/* 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, tomstdenis@gmail.com
+ */
+#include <tfm.h>
+
+int fp_radix_size(fp_int *a, int radix, int *size)
+{
+  int     digs;
+  fp_int  t;
+  fp_digit d;
+   
+  *size = 0;
+
+  /* check range of the radix */
+  if (radix < 2 || radix > 64) {
+    return FP_VAL;
+  }
+
+  /* quick out if its zero */
+  if (fp_iszero(a) == 1) {
+     *size = 2;
+     return FP_OKAY;
+  }
+
+  fp_init_copy(&t, a);
+
+  /* if it is negative output a - */
+  if (t.sign == FP_NEG) {
+    (*size)++;
+    t.sign = FP_ZPOS;
+  }
+
+  digs = 0;
+  while (fp_iszero (&t) == FP_NO) {
+    fp_div_d (&t, (fp_digit) radix, &t, &d);
+    (*size)++;
+  }
+
+  /* append a NULL so the string is properly terminated */
+  (*size)++;
+  return FP_OKAY;
+
+}
+
+/* $Source: /cvs/libtom/tomsfastmath/src/bin/fp_radix_size.c,v $ */
+/* $Revision: 1.1 $ */
+/* $Date: 2006/12/31 21:25:53 $ */