use size_t

When dealing with in-memory lengths, the standard type "size_t" should
be used.  Missing one can be quite dangerous, because an attacker
could provoke an integer under-/overflow, which may provide an attack
vector.

git-svn-id: https://svn.musicpd.org/mpd/trunk@7205 09075e82-0dd4-0310-85a5-a0d7c8717e4f

src/myfprintf.c

@@ -30,7 +30,7 @@ static void blockingWrite(const int fd, const char *string, size_t len)
 {
 	while (len) {
 		ssize_t ret = xwrite(fd, string, len);
-		if (ret == len)
+		if (ret == (ssize_t)len)
 			return;
 		if (ret >= 0) {
 			len -= ret;