tweak to zero-width tables

git-svn-id: https://svn.r-project.org/R/trunk@80276 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: ripley

src/main/rlocale.c

@@ -128,9 +128,9 @@ static int wcwidthsearch(int wint, const struct interval_wcwidth *table,
     int mid;
     max--;
 
-    /* This quickly gives one for ASCII characters since the table
-       starts at 0xa1 */
-    if (wint < table[0].first || wint > table[max].last) return 1;
+    /* This quickly gives one for printing ASCII characters */
+    if (wint > 0x1F && wint < 0x7F) return 1;
+    else if (wint < table[min].first || wint > table[max].last) return -1;
     while (max >= min) {
 	mid = (min + max) / 2;
 	if (wint > table[mid].last)