X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/71458b3b2492943349f7693a46792756d5013c69..10c5b65eb8fefdf84cdb631edcd18160effcdf7e:/sbr/uprf.c

diff --git a/sbr/uprf.c b/sbr/uprf.c
index 500b036d..c74af7bd 100644
--- a/sbr/uprf.c
+++ b/sbr/uprf.c
@@ -1,6 +1,4 @@
-
-/*
- * uprf.c -- "unsigned" lexical prefix
+/* uprf.c -- "unsigned" lexical prefix
  *
  * This code is Copyright (c) 2002, by the authors of nmh.  See the
  * COPYRIGHT file in the root directory of the nmh distribution for
@@ -10,24 +8,22 @@
 #include <h/mh.h>
 
 
+/* uprf returns true if s starts with prefix, ignoring case.
+ * Otherwise false.  If s or prefix are NULL then false results. */
 int
-uprf (char *c1, char *c2)
+uprf(const char *s, const char *prefix)
 {
-    int c, mask;
+    unsigned char *us, *up;
 
-    if (!(c1 && c2))
+    if (!s || !prefix)
 	return 0;
+    us = (unsigned char *)s;
+    up = (unsigned char *)prefix;
 
-    while ((c = *c2++))
-    {
-	c &= 0xff;
-	mask = *c1 & 0xff;
-	c = (isalpha(c) && isupper(c)) ? tolower(c) : c;
-	mask = (isalpha(mask) && isupper(mask)) ? tolower(mask) : mask;
-	if (c != mask)
-	    return 0;
-	else
-	    c1++;
+    while (*us && tolower(*us) == tolower(*up)) {
+        us++;
+        up++;
     }
-    return 1;
+
+    return *up == '\0';
 }