X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/f654f4218ac36981a1174b1f09823997239b0358..2b645fb792c62ae0d38fcde4c39e1bd0889b0e06:/mptext.h

diff --git a/mptext.h b/mptext.h
index c6e8275..57c4dc2 100644
--- a/mptext.h
+++ b/mptext.h
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: mptext.h,v 1.4 2000/06/17 11:46:58 mdw Exp $
+ * $Id: mptext.h,v 1.6 2002/10/15 22:58:29 mdw Exp $
  *
  * Textual representation of multiprecision numbers
  *
@@ -30,6 +30,12 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: mptext.h,v $
+ * Revision 1.6  2002/10/15 22:58:29  mdw
+ * Fast estimation of number representation lengths.
+ *
+ * Revision 1.5  2000/10/08 12:04:58  mdw
+ * (MP_DOFPRINTFR): cope with null pointers.
+ *
  * Revision 1.4  2000/06/17 11:46:58  mdw
  * Convenience macros for producing debugging output containing MP
  * integers.
@@ -104,6 +110,20 @@ extern mp *mp_read(mp */*m*/, int /*radix*/,
 extern int mp_write(mp */*m*/, int /*radix*/,
 		    const mptext_ops */*ops*/, void */*p*/);
 
+/* --- @mptext_len@ --- *
+ *
+ * Arguments:	@mp *x@ = number to work on
+ *		@int r@ = radix the number will be expressed in
+ *
+ * Returns:	The number of digits needed to represent the number in the
+ *		given base.  This will not include space for a leading sign
+ *		(use @MP_ISNEG@ to check that, or just add one on for luck);
+ *		neither will it add space for a terminating null.  In general
+ *		the answer will be an overestimate.
+ */
+
+extern size_t mptext_len(mp */*x*/, int /*r*/);
+
 /*----- File I/O ----------------------------------------------------------*/
 
 #include <stdio.h>
@@ -122,7 +142,10 @@ extern int mp_writefile(mp */*m*/, FILE */*fp*/, int /*radix*/);
 
 #define MP_DOFPRINTFR(fp, args, m, r) do {				\
   fprintf args;								\
-  mp_writefile(m, fp, r);						\
+  if (m)								\
+    mp_writefile(m, fp, r);						\
+  else									\
+    fputs("<null>", fp);						\
   fputc('\n', fp);							\
 } while (0)