LAPD: Propagate lapd_receive() errors to the E1 driver
Scenario: BTS are configured and working, then the BSC stops working
for some reason (crash or administrative stop).
If the BSC comes back to life, LAPD among other things does not know
about the previous existing TEIs. Instead of ignoring these frames,
we notify the driver that we are seeing frames with unknown TEIs, so
it can try to recover, e.g. by resending the SABM message.
diff --git a/include/osmocom/abis/lapd.h b/include/osmocom/abis/lapd.h
index fb980d1..dd22028 100644
--- a/include/osmocom/abis/lapd.h
+++ b/include/osmocom/abis/lapd.h
@@ -26,8 +26,20 @@
struct llist_head tei_list; /* list of TEI in this LAPD instance */
};
-extern uint8_t *lapd_receive(struct lapd_instance *li, uint8_t *data, unsigned int len,
- int *ilen, lapd_mph_type *prim);
+enum lapd_recv_errors {
+ LAPD_ERR_NONE = 0,
+ LAPD_ERR_BAD_LEN,
+ LAPD_ERR_BAD_ADDR,
+ LAPD_ERR_UNKNOWN_S_CMD,
+ LAPD_ERR_UNKNOWN_U_CMD,
+ LAPD_ERR_UNKNOWN_TEI,
+ LAPD_ERR_BAD_CMD,
+ __LAPD_ERR_MAX
+};
+
+extern uint8_t *lapd_receive(struct lapd_instance *li, uint8_t *data,
+ unsigned int len, int *ilen, lapd_mph_type *prim,
+ int *error);
extern void lapd_transmit(struct lapd_instance *li, uint8_t tei, uint8_t sapi,
uint8_t *data, unsigned int len);