i460: pass more context to call-back functions

When calling a user-provided call-back function for the i460 mux
or demux, always pass a pointer to the osmo_i460_subchan the callback
relates to.  This way, the user can walk the i460 data structures
to obtain information about which mux/demux instances is calling.

Change-Id: Id842c72ce371a67fe5df6694e195c281aaf607ab

3 files changed, 14 insertions, 9 deletions

diff --git a/include/osmocom/gsm/i460_mux.h b/include/osmocom/gsm/i460_mux.h
index e7ea9bd5..8e392434 100644
--- a/include/osmocom/gsm/i460_mux.h
+++ b/include/osmocom/gsm/i460_mux.h
@@ -36,8 +36,12 @@ enum osmo_i460_rate {
 	OSMO_I460_RATE_8k,
 };
 
-typedef void (*out_cb_bits_t)(void *user_data, const ubit_t *bits, unsigned int num_bits);
-typedef void (*out_cb_bytes_t)(void *user_data, const uint8_t *bytes, unsigned int num_bytes);
+struct osmo_i460_subchan;
+
+typedef void (*out_cb_bits_t)(struct osmo_i460_subchan *schan, void *user_data,
+			      const ubit_t *bits, unsigned int num_bits);
+typedef void (*out_cb_bytes_t)(struct osmo_i460_subchan *schan, void *user_data,
+			       const uint8_t *bytes, unsigned int num_bytes);
 
 struct osmo_i460_subchan_demux {
 	/*! bit-buffer for output bits */
@@ -52,7 +56,7 @@ struct osmo_i460_subchan_demux {
 	void *user_data;
 };
 
-typedef void (*in_cb_queue_empty_t)(void *user_data);
+typedef void (*in_cb_queue_empty_t)(struct osmo_i460_subchan *schan, void *user_data);
 
 struct osmo_i460_subchan_mux {
 	/*! list of to-be-transmitted message buffers */
diff --git a/src/gsm/i460_mux.c b/src/gsm/i460_mux.c
index 3b2a589f..320e781b 100644
--- a/src/gsm/i460_mux.c
+++ b/src/gsm/i460_mux.c
@@ -69,14 +69,14 @@ static void demux_subchan_append_bit(struct osmo_i460_subchan *schan, uint8_t bi
 
 	if (demux->out_idx >= demux->out_bitbuf_size) {
 		if (demux->out_cb_bits)
-			demux->out_cb_bits(demux->user_data, demux->out_bitbuf, demux->out_idx);
+			demux->out_cb_bits(schan, demux->user_data, demux->out_bitbuf, demux->out_idx);
 		else {
 			/* pack bits into bytes */
 			OSMO_ASSERT((demux->out_idx % 8) == 0);
 			unsigned int num_bytes = demux->out_idx / 8;
 			uint8_t bytes[num_bytes];
 			osmo_ubit2pbit(bytes, demux->out_bitbuf, demux->out_idx);
-			demux->out_cb_bytes(demux->user_data, bytes, num_bytes);
+			demux->out_cb_bytes(schan, demux->user_data, bytes, num_bytes);
 		}
 		demux->out_idx = 0;
 	}
@@ -137,11 +137,11 @@ void osmo_i460_demux_in(struct osmo_i460_timeslot *ts, const uint8_t *data, size
 		schan = &ts->schan[0];
 		demux = &schan->demux;
 		if (demux->out_cb_bytes)
-			demux->out_cb_bytes(demux->user_data, data, data_len);
+			demux->out_cb_bytes(schan, demux->user_data, data, data_len);
 		else {
 			ubit_t bits[data_len*8];
 			osmo_pbit2ubit(bits, data, data_len*8);
-			demux->out_cb_bits(demux->user_data, bits, data_len*8);
+			demux->out_cb_bits(schan, demux->user_data, bits, data_len*8);
 		}
 		return;
 	}
@@ -178,7 +178,7 @@ static ubit_t mux_schan_provide_bit(struct osmo_i460_subchan *schan)
 	if (llist_empty(&mux->tx_queue)) {
 		/* User code now has a last chance to put something into the queue. */
 		if (mux->in_cb_queue_empty)
-			mux->in_cb_queue_empty(mux->user_data);
+			mux->in_cb_queue_empty(schan, mux->user_data);
 
 		/* If the queue is still empty, return idle bits */
 		if (llist_empty(&mux->tx_queue))
diff --git a/tests/i460_mux/i460_mux_test.c b/tests/i460_mux/i460_mux_test.c
index 53144fde..d63b2ae6 100644
--- a/tests/i460_mux/i460_mux_test.c
+++ b/tests/i460_mux/i460_mux_test.c
@@ -3,7 +3,8 @@
 
 #include <osmocom/gsm/i460_mux.h>
 
-static void bits_cb(void *user_data, const ubit_t *bits, unsigned int num_bits)
+static void bits_cb(struct osmo_i460_subchan *schan, void *user_data,
+		    const ubit_t *bits, unsigned int num_bits)
 {
 	char *str = user_data;
 	printf("demux_bits_cb '%s': %s\n", str, osmo_ubit_dump(bits, num_bits));