2005-04-05 Dave Korn <dave.korn@artimi.com>

        * libc/stdio/vfscanf.c (__svfscanf_r): If an error occurs processing
        something that looks like a "NaN", put back the characters processed.

diff --git a/newlib/libc/stdio/vfscanf.c b/newlib/libc/stdio/vfscanf.c
index 621ea23..80c652a 100644 (file)
--- a/newlib/libc/stdio/vfscanf.c
+++ b/newlib/libc/stdio/vfscanf.c
@@ -1111,7 +1111,24 @@ _DEFUN(__SVFSCANF_R, (rptr, fp, fmt0, ap),
            }
          if (zeroes)
            flags &= ~NDIGITS;
-         /*
+          /* We may have a 'N' or possibly even a 'Na' as the start of 'NaN', 
+            only to run out of chars before it was complete (or having 
+            encountered a non- matching char).  So check here if we have an 
+            outstanding nancount, and if so put back the chars we did 
+            swallow and treat as a failed match. */
+          if (nancount && nancount != 3)
+            {
+              /* Ok... what are we supposed to do in the event that the
+              __srefill call above was triggered in the middle of the partial
+              'NaN' and so we can't put it all back? */
+              while (nancount-- && (p > buf))
+                {
+                  ungetc (*(u_char *)--p, fp);
+                  --nread;
+                }
+              goto match_failure;
+            }
+          /*
           * If no digits, might be missing exponent digits
           * (just give back the exponent) or might be missing
           * regular digits, but had sign and/or decimal point.
@@ -1123,7 +1140,7 @@ _DEFUN(__SVFSCANF_R, (rptr, fp, fmt0, ap),
                  /* no digits at all */
                  while (p > buf)
                     {
-                     ungetc (*(u_char *)-- p, fp);
+                     ungetc (*(u_char *)--p, fp);
                       --nread;
                     }
                  goto match_failure;