}
-/*
- * Scan for any 8-bit characters. Return 1 if they exist.
- *
- * Scan up until the given endpoint (but not the actual endpoint itself).
- * If the endpoint is NULL, scan until a '\0' is reached.
- */
-
-int
-contains8bit(const char *start, const char *end)
+/* contains8bit returns true if any byte from start onwards fails
+ * isascii(3), i.e. is outside [0, 0x7f]. If start is NULL it returns
+ * false. Bytes are examined until a NUL byte, or, if end is not NULL,
+ * whilst start is before end. */
+bool contains8bit(const char *start, const char *end)
{
- if (! start)
- return 0;
+ const char *p;
+ char c;
- while (*start != '\0' && (!end || (start < end)))
- if (! isascii((unsigned char) *start++))
- return 1;
+ if (!start)
+ return false;
- return 0;
+ p = start;
+ if (end) {
+ while (p < end && (c = (*p++)))
+ if (!isascii((unsigned char)c))
+ return true;
+ } else {
+ while ((c = (*p++)))
+ if (!isascii((unsigned char)c))
+ return true;
+ }
+
+ return false;
}