Don't trust isspace() unless isascii() approves

We have seen isspace(0xC3) return true on windows so we need to do
something about this.

As a wise man said:
Using "isspace()" and friends on anything but the 0-127 range is just
fraught with danger, regardless of platform.

We remedy this by checking that isascii() says that its a 7-bit ascii
character, something isspace() knows how to handle

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

save-xml.c

@@ -35,12 +35,15 @@ static void show_utf8(struct membuffer *b, const char *text, const char *pre, co
 	if (!text)
 		return;
 	/* remove leading and trailing space */
-	while (isspace(*text))
+	/* We need to combine isascii() with isspace(),
+	 * because we can only trust isspace() with 7-bit ascii,
+	 * on windows for example */
+	while (isascii(*text) && isspace(*text))
 		text++;
 	len = strlen(text);
 	if (!len)
 		return;
-	while (len && isspace(text[len - 1]))
+	while (len && isascii(text[len - 1]) && isspace(text[len - 1]))
 		len--;
 	/* strndup would be easier, but that doesn't appear to exist on Windows / Mac */
 	cleaned = strdup(text);