commit files needed for zpm-fetchurl

[zpackage] / tomsfastmath / src / bin / fp_toradix_n.c

diff --git a/tomsfastmath/src/bin/fp_toradix_n.c b/tomsfastmath/src/bin/fp_toradix_n.c
new file mode 100644 (file)
index 0000000..5c9bf62
--- /dev/null
+++ b/tomsfastmath/src/bin/fp_toradix_n.c
@@ -0,0 +1,71 @@
+/* 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_private.h>
+
+int fp_toradix_n(fp_int *a, char *str, int radix, int maxlen)
+{
+   int digs;
+   fp_int t;
+   fp_digit d;
+   char *_s = str;
+
+   /* check range of the radix */
+   if (maxlen < 2 || radix < 2 || radix > 64)
+      return FP_VAL;
+
+   /* quick check for zero */
+   if (fp_iszero(a) == FP_YES) {
+      *str++ = '0';
+      *str = '\0';
+      return FP_OKAY;
+   }
+
+   fp_init_copy(&t, a);
+
+   /* if it is negative output a - */
+   if (t.sign == FP_NEG) {
+      /* we have to reverse our digits later... but not the - sign!! */
+      ++_s;
+
+      /* store the flag and mark the number as positive */
+      *str++ = '-';
+      t.sign = FP_ZPOS;
+
+      /* subtract a char */
+      --maxlen;
+   }
+
+   digs = 0;
+   while (fp_iszero (&t) == FP_NO) {
+      if (--maxlen < 1) {
+         /* no more room */
+         break;
+      }
+      fp_div_d(&t, (fp_digit) radix, &t, &d);
+      *str++ = fp_s_rmap[d];
+      ++digs;
+   }
+
+   /* reverse the digits of the string.  In this case _s points
+    * to the first digit [exluding the sign] of the number]
+    */
+   fp_reverse((unsigned char *) _s, digs);
+
+   /* append a NULL so the string is properly terminated */
+   *str = '\0';
+
+   if (maxlen < 1)
+      return FP_VAL;
+   return FP_OKAY;
+}
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */