src: add generic channel infrastructure and A-bis IPA server support

This patch adds the generic channel infrastructure that allows to
create channel of different types. Each channel has their own
configuration functions.

  struct osmo_chan *chan;
  chan = osmo_chan_create(tall_example, CHAN_ABIS_IPA_SERVER);
  ...

  /* specific configuration functions per supported channel. */
  osmo_chan_abis_ipa_server_set_cb_signalmsg(chan, signal_msg_cb);
  osmo_chan_abis_ipa_unit_add(chan, 1801, 0);

  /* open channel. */
  osmo_chan_open(chan);

The input path requires a callback to be registered. The output path
is handled through:

  int osmo_chan_enqueue(struct osmo_chan *c, struct msgb *msg);

The msg->dst must be set (it can be taken from the original message
to route one reply).

This patch also adds A-bis IPA server support. It has been tested with
e1inp_ipa_bsc_test available in libosmo-abis.

1 files changed, 14 insertions, 0 deletions

diff --git a/include/osmocom/netif/channel/abis_ipa_server.h b/include/osmocom/netif/channel/abis_ipa_server.h
new file mode 100644
index 0000000..0338021
--- /dev/null
+++ b/include/osmocom/netif/channel/abis_ipa_server.h
@@ -0,0 +1,14 @@
+#ifndef _ABIS_IPA_SERVER_H_
+#define _ABIS_IPA_SERVER_H_
+
+void osmo_chan_abis_ipa_server_set_oml_addr(struct osmo_chan *c, const char *addr);
+void osmo_chan_abis_ipa_server_set_oml_port(struct osmo_chan *c, uint16_t port);
+
+void osmo_chan_abis_ipa_server_set_rsl_addr(struct osmo_chan *c, const char *addr);
+void osmo_chan_abis_ipa_server_set_rsl_port(struct osmo_chan *c, uint16_t port);
+
+void osmo_chan_abis_ipa_server_set_cb_signalmsg(struct osmo_chan *c, void (*signal_msg)(struct msgb *msg, int type));
+
+int osmo_chan_abis_ipa_unit_add(struct osmo_chan *c, uint16_t site_id, uint16_t bts_id);
+
+#endif