assert_return(errno > 0, -EINVAL);
return -errno;
}
+
+/* Hint #1: ENETUNREACH happens if we try to connect to "non-existing" special IP addresses, such as ::5.
+ *
+ * Hint #2: The kernel sends e.g., EHOSTUNREACH or ENONET to userspace in some ICMP error cases. See the
+ * icmp_err_convert[] in net/ipv4/icmp.c in the kernel sources */
+#define ERRNO_IS_DISCONNECT(r) \
+ IN_SET(abs(r), \
+ ENOTCONN, ECONNRESET, ECONNREFUSED, ECONNABORTED, EPIPE, \
+ ENETUNREACH, EHOSTUNREACH, ENOPROTOOPT, EHOSTDOWN, ENONET)
+
+/* Resource exhaustion, could be our fault or general system trouble */
+#define ERRNO_IS_RESOURCE(r) \
+ IN_SET(abs(r), ENOMEM, EMFILE, ENFILE)