X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/2b26f2d79b3c5342a0daaba359cc00e13de2a9ca..f1140c41e9297d14386ee18fbed7a9686d223024:/mptext.c

diff --git a/mptext.c b/mptext.c
index f408b90..a55f1c0 100644
--- a/mptext.c
+++ b/mptext.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: mptext.c,v 1.5 2000/06/17 11:46:19 mdw Exp $
+ * $Id: mptext.c,v 1.8 2000/12/06 20:32:42 mdw Exp $
  *
  * Textual representation of multiprecision numbers
  *
@@ -30,6 +30,16 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: mptext.c,v $
+ * Revision 1.8  2000/12/06 20:32:42  mdw
+ * Reduce binary bytes (to allow marker bits to be ignored).  Fix error
+ * message string a bit.  Allow leading `+' signs.
+ *
+ * Revision 1.7  2000/07/15 10:01:08  mdw
+ * Bug fix in binary input.
+ *
+ * Revision 1.6  2000/06/25 12:58:23  mdw
+ * Fix the derivation of `depth' commentary.
+ *
  * Revision 1.5  2000/06/17 11:46:19  mdw
  * New and much faster stack-based algorithm for reading integers.  Support
  * reading and writing binary integers in bases between 2 and 256.
@@ -64,12 +74,13 @@
  *
  * This is the number of bits in a @size_t@ object.  Why? 
  *
- * Just to convince yourself that this is correct: let @b = MPW_MAX + 1@.
- * Then the largest possible @mp@ is %$M - 1$% where %$M = b^Z$%.  Let %$r$%
- * be a radix to read or write.  Since the recursion squares the radix at
- * each step, the highest number reached by the recursion is %$d$%, where:
+ * To see this, let %$b = \mathit{MPW\_MAX} + 1$% and let %$Z$% be the
+ * largest @size_t@ value.  Then the largest possible @mp@ is %$M - 1$% where
+ * %$M = b^Z$%.  Let %$r$% be a radix to read or write.  Since the recursion
+ * squares the radix at each step, the highest number reached by the
+ * recursion is %$d$%, where:
  *
- *   %$r^(2^d) = b^Z$%.
+ *   %$r^{2^d} = b^Z$%.
  *
  * Solving gives that %$d = \lg \log_r b^Z$%.  If %$r = 2$%, this is maximum,
  * so choosing %$d = \lg \lg b^Z = \lg (Z \lg b) = \lg Z + \lg \lg b$%.
@@ -162,11 +173,10 @@ mp *mp_read(mp *m, int radix, const mptext_ops *ops, void *p)
 
   /* --- Handle an initial sign --- */
 
-  if (ch == '-') {
-    f |= f_neg;
-    ch = ops->get(p);
-    while (isspace(ch))
-      ch = ops->get(p);
+  if (radix >= 0 && (ch == '-' || ch == '+')) {
+    if (ch == '-')
+      f |= f_neg;
+    do ch = ops->get(p); while isspace(ch);
   }
 
   /* --- If the radix is zero, look for leading zeros --- */
@@ -177,7 +187,7 @@ mp *mp_read(mp *m, int radix, const mptext_ops *ops, void *p)
     r = -1;
   } else if (radix < 0) {
     rd = -radix;
-    assert(((void)"binary radix must fit in a byte ", rd < UCHAR_MAX));
+    assert(((void)"binary radix must fit in a byte", rd < UCHAR_MAX));
     r = -1;
   } else if (ch != '0') {
     rd = 10;
@@ -199,6 +209,9 @@ mp *mp_read(mp *m, int radix, const mptext_ops *ops, void *p)
   for (;; ch = ops->get(p)) {
     int x;
 
+    if (ch < 0)
+      break;
+
     /* --- An underscore indicates a numbered base --- */
 
     if (ch == '_' && r > 0 && r <= 36) {
@@ -224,7 +237,7 @@ mp *mp_read(mp *m, int radix, const mptext_ops *ops, void *p)
     /* --- Check that the character is a digit and in range --- */
 
     if (radix < 0)
-      x = ch;
+      x = ch % rd;
     else {
       if (!isalnum(ch))
 	break;