wider selftest coverage

ext/picotcp/include/pico_stack.h

@@ -9,7 +9,7 @@
 #include "pico_config.h"
 #include "pico_frame.h"
 
-#define PICO_MAX_TIMERS 20
+#define PICO_MAX_TIMERS 128
 
 #define PICO_ETH_MRU (1514u)
 #define PICO_IP_MRU (1500u)
@@ -78,6 +78,16 @@ int pico_notify_ttl_expired(struct pico_frame *f);
 int pico_notify_frag_expired(struct pico_frame *f);
 int pico_notify_pkt_too_big(struct pico_frame *f);
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int pico_ntimers();
+
+#ifdef __cplusplus
+}
+#endif
+
 /* Various. */
 int pico_source_is_local(struct pico_frame *f);
 int pico_frame_dst_is_unicast(struct pico_frame *f);