input: Add sr_input_end().

This signifies to the module instance no more input will come. This
will cause the module to process any data it may have buffered. The
SR_DF_END packet will also typically be sent at this time.

include/libsigrok/proto.h

@@ -137,6 +137,7 @@ SR_API int sr_input_scan_buffer(GString *buf, const struct sr_input **in);
 SR_API int sr_input_scan_file(const char *filename, const struct sr_input **in);
 SR_API struct sr_dev_inst *sr_input_dev_inst_get(const struct sr_input *in);
 SR_API int sr_input_send(const struct sr_input *in, GString *buf);
+SR_API int sr_input_end(const struct sr_input *in);
 SR_API int sr_input_free(const struct sr_input *in);
 
 /*--- output/output.c -------------------------------------------------------*/

src/backend.c

@@ -246,6 +246,10 @@ static int sanity_check_all_input_modules(void)
 			sr_err("No receive in module %d ('%s').", i, d);
 			errors++;
 		}
+		if (!inputs[i]->end) {
+			sr_err("No end in module %d ('%s').", i, d);
+			errors++;
+		}
 
 		if (errors == 0)
 			continue;

src/input/binary.c

@@ -64,7 +64,7 @@ static int init(struct sr_input *in, GHashTable *options)
 	return SR_OK;
 }
 
-static int receive(struct sr_input *in, GString *buf)
+static int process_buffer(struct sr_input *in)
 {
 	struct sr_datafeed_packet packet;
 	struct sr_datafeed_meta meta;
@@ -72,20 +72,9 @@ static int receive(struct sr_input *in, GString *buf)
 	struct sr_config *src;
 	struct context *inc;
 	gsize chunk_size, i;
-	int chunk, num_channels;
+	int chunk;
 
 	inc = in->priv;
-
-	g_string_append_len(in->buf, buf->str, buf->len);
-
-	num_channels = g_slist_length(in->sdi->channels);
-
-	if (!in->sdi_ready) {
-		/* sdi is ready, notify frontend. */
-		in->sdi_ready = TRUE;
-		return SR_OK;
-	}
-
 	if (!inc->started) {
 		std_session_send_df_header(in->sdi, LOG_PREFIX);
 
@@ -103,7 +92,7 @@ static int receive(struct sr_input *in, GString *buf)
 
 	packet.type = SR_DF_LOGIC;
 	packet.payload = &logic;
-	logic.unitsize = (num_channels + 7) / 8;
+	logic.unitsize = (g_slist_length(in->sdi->channels) + 7) / 8;
 
 	/* Cut off at multiple of unitsize. */
 	chunk_size = in->buf->len / logic.unitsize * logic.unitsize;
@@ -120,21 +109,41 @@ static int receive(struct sr_input *in, GString *buf)
 	return SR_OK;
 }
 
-static int cleanup(struct sr_input *in)
+static int receive(struct sr_input *in, GString *buf)
+{
+	int ret;
+
+	g_string_append_len(in->buf, buf->str, buf->len);
+
+	if (!in->sdi_ready) {
+		/* sdi is ready, notify frontend. */
+		in->sdi_ready = TRUE;
+		return SR_OK;
+	}
+
+	ret = process_buffer(in);
+
+	return ret;
+}
+
+static int end(struct sr_input *in)
 {
 	struct context *inc;
 	struct sr_datafeed_packet packet;
+	int ret;
+
+	if (in->sdi_ready)
+		ret = process_buffer(in);
+	else
+		ret = SR_OK;
 
 	inc = in->priv;
-	if (!inc)
-		return SR_OK;
-
 	if (inc->started) {
 		packet.type = SR_DF_END;
 		sr_session_send(in->sdi, &packet);
 	}
 
-	return SR_OK;
+	return ret;
 }
 
 static struct sr_option options[] = {
@@ -160,5 +169,5 @@ SR_PRIV struct sr_input_module input_binary = {
 	.options = get_options,
 	.init = init,
 	.receive = receive,
-	.cleanup = cleanup,
+	.end = end,
 };

src/input/chronovu_la8.c

@@ -76,7 +76,7 @@ static int init(struct sr_input *in, GHashTable *options)
 	return SR_OK;
 }
 
-static int receive(struct sr_input *in, GString *buf)
+static int process_buffer(struct sr_input *in)
 {
 	struct sr_datafeed_packet packet;
 	struct sr_datafeed_meta meta;
@@ -84,20 +84,9 @@ static int receive(struct sr_input *in, GString *buf)
 	struct sr_config *src;
 	struct context *inc;
 	gsize chunk_size, i;
-	int chunk, num_channels;
+	int chunk;
 
 	inc = in->priv;
-
-	g_string_append_len(in->buf, buf->str, buf->len);
-
-	num_channels = g_slist_length(in->sdi->channels);
-
-	if (!in->sdi_ready) {
-		/* sdi is ready, notify frontend. */
-		in->sdi_ready = TRUE;
-		return SR_OK;
-	}
-
 	if (!inc->started) {
 		std_session_send_df_header(in->sdi, LOG_PREFIX);
 
@@ -115,7 +104,7 @@ static int receive(struct sr_input *in, GString *buf)
 
 	packet.type = SR_DF_LOGIC;
 	packet.payload = &logic;
-	logic.unitsize = (num_channels + 7) / 8;
+	logic.unitsize = (g_slist_length(in->sdi->channels) + 7) / 8;
 
 	/* Cut off at multiple of unitsize. */
 	chunk_size = in->buf->len / logic.unitsize * logic.unitsize;
@@ -132,21 +121,41 @@ static int receive(struct sr_input *in, GString *buf)
 	return SR_OK;
 }
 
-static int cleanup(struct sr_input *in)
+static int receive(struct sr_input *in, GString *buf)
+{
+	int ret;
+
+	g_string_append_len(in->buf, buf->str, buf->len);
+
+	if (!in->sdi_ready) {
+		/* sdi is ready, notify frontend. */
+		in->sdi_ready = TRUE;
+		return SR_OK;
+	}
+
+	ret = process_buffer(in);
+
+	return ret;
+}
+
+static int end(struct sr_input *in)
 {
 	struct context *inc;
 	struct sr_datafeed_packet packet;
+	int ret;
+
+	if (in->sdi_ready)
+		ret = process_buffer(in);
+	else
+		ret = SR_OK;
 
 	inc = in->priv;
-	if (!inc)
-		return SR_OK;
-
 	if (inc->started) {
 		packet.type = SR_DF_END;
 		sr_session_send(in->sdi, &packet);
 	}
 
-	return SR_OK;
+	return ret;
 }
 
 static struct sr_option options[] = {
@@ -174,5 +183,5 @@ SR_PRIV struct sr_input_module input_chronovu_la8 = {
 	.format_match = format_match,
 	.init = init,
 	.receive = receive,
-	.cleanup = cleanup,
+	.end = end,
 };

src/input/csv.c

@@ -610,7 +610,7 @@ static int initial_receive(const struct sr_input *in)
 	return ret;
 }
 
-static int receive(struct sr_input *in, GString *buf)
+static int process_buffer(struct sr_input *in)
 {
 	struct sr_datafeed_packet packet;
 	struct sr_datafeed_meta meta;
@@ -621,21 +621,7 @@ static int receive(struct sr_input *in, GString *buf)
 	int max_columns, ret, l;
 	char *p, **lines, **columns;
 
-	g_string_append_len(in->buf, buf->str, buf->len);
-
 	inc = in->priv;
-	if (!inc->termination) {
-		if ((ret = initial_receive(in)) == SR_ERR_NA)
-			/* Not enough data yet. */
-			return SR_OK;
-		else if (ret != SR_OK)
-			return SR_ERR;
-
-		/* sdi is ready, notify frontend. */
-		in->sdi_ready = TRUE;
-		return SR_OK;
-	}
-
 	if (!inc->started) {
 		std_session_send_df_header(in->sdi, LOG_PREFIX);
 
@@ -723,24 +709,61 @@ static int receive(struct sr_input *in, GString *buf)
 	g_strfreev(lines);
 	g_string_erase(in->buf, 0, p - in->buf->str + 1);
 
-	return SR_OK;
+	return ret;
 }
 
-static int cleanup(struct sr_input *in)
+static int receive(struct sr_input *in, GString *buf)
+{
+	struct context *inc;
+	int ret;
+
+	g_string_append_len(in->buf, buf->str, buf->len);
+
+	inc = in->priv;
+	if (!inc->termination) {
+		if ((ret = initial_receive(in)) == SR_ERR_NA)
+			/* Not enough data yet. */
+			return SR_OK;
+		else if (ret != SR_OK)
+			return SR_ERR;
+
+		/* sdi is ready, notify frontend. */
+		in->sdi_ready = TRUE;
+		return SR_OK;
+	}
+
+	ret = process_buffer(in);
+
+	return ret;
+}
+
+static int end(struct sr_input *in)
 {
 	struct context *inc;
 	struct sr_datafeed_packet packet;
+	int ret;
+
+	if (in->sdi_ready)
+		ret = process_buffer(in);
+	else
+		ret = SR_OK;
 
 	inc = in->priv;
-	if (!inc)
-		return SR_OK;
-
 	if (inc->started) {
 		/* End of stream. */
 		packet.type = SR_DF_END;
 		sr_session_send(in->sdi, &packet);
 	}
 
+	return ret;
+}
+
+static int cleanup(struct sr_input *in)
+{
+	struct context *inc;
+
+	inc = in->priv;
+
 	if (inc->delimiter)
 		g_string_free(inc->delimiter, TRUE);
 
@@ -795,5 +818,6 @@ SR_PRIV struct sr_input_module input_csv = {
 	.format_match = format_match,
 	.init = init,
 	.receive = receive,
+	.end = end,
 	.cleanup = cleanup,
 };

src/input/input.c

@@ -529,6 +529,20 @@ SR_API int sr_input_send(const struct sr_input *in, GString *buf)
 	return in->module->receive((struct sr_input *)in, buf);
 }
 
+/**
+ * Signal the input module no more data will come.
+ *
+ * This will cause the module to process any data it may have buffered.
+ * The SR_DF_END packet will also typically be sent at this time.
+ *
+ * @since 0.4.0
+ */
+SR_API int sr_input_end(const struct sr_input *in)
+{
+	sr_spew("Calling end() on %s module.", in->module->id);
+	return in->module->end((struct sr_input *)in);
+}
+
 /**
  * Free the specified input instance and all associated resources.
  *

src/input/vcd.c

@@ -457,7 +457,7 @@ static gboolean have_header(GString *buf)
 	return FALSE;
 }
 
-static int receive(struct sr_input *in, GString *buf)
+static int process_buffer(struct sr_input *in)
 {
 	struct sr_datafeed_packet packet;
 	struct sr_datafeed_meta meta;
@@ -466,21 +466,7 @@ static int receive(struct sr_input *in, GString *buf)
 	uint64_t samplerate;
 	char *p;
 
-	g_string_append_len(in->buf, buf->str, buf->len);
-
 	inc = in->priv;
-	if (!inc->got_header) {
-		if (!have_header(in->buf))
-			return SR_OK;
-		if (!parse_header(in, in->buf) != SR_OK)
-			/* There was a header in there, but it was malformed. */
-			return SR_ERR;
-
-		in->sdi_ready = TRUE;
-		/* sdi is ready, notify frontend. */
-		return SR_OK;
-	}
-
 	if (!inc->started) {
 		std_session_send_df_header(in->sdi, LOG_PREFIX);
 
@@ -506,18 +492,56 @@ static int receive(struct sr_input *in, GString *buf)
 	return SR_OK;
 }
 
-static int cleanup(struct sr_input *in)
+static int receive(struct sr_input *in, GString *buf)
+{
+	struct context *inc;
+	int ret;
+
+	g_string_append_len(in->buf, buf->str, buf->len);
+
+	inc = in->priv;
+	if (!inc->got_header) {
+		if (!have_header(in->buf))
+			return SR_OK;
+		if (!parse_header(in, in->buf) != SR_OK)
+			/* There was a header in there, but it was malformed. */
+			return SR_ERR;
+
+		in->sdi_ready = TRUE;
+		/* sdi is ready, notify frontend. */
+		return SR_OK;
+	}
+
+	ret = process_buffer(in);
+
+	return ret;
+}
+
+static int end(struct sr_input *in)
 {
 	struct sr_datafeed_packet packet;
 	struct context *inc;
+	int ret;
+
+	if (in->sdi_ready)
+		ret = process_buffer(in);
+	else
+		ret = SR_OK;
 
 	inc = in->priv;
 	if (inc->started) {
-		/* End of stream. */
 		packet.type = SR_DF_END;
 		sr_session_send(in->sdi, &packet);
 	}
 
+	return ret;
+}
+
+static int cleanup(struct sr_input *in)
+{
+	struct context *inc;
+
+	inc = in->priv;
 	g_slist_free_full(inc->channels, free_channel);
 
 	return SR_OK;
@@ -552,5 +576,6 @@ SR_PRIV struct sr_input_module input_vcd = {
 	.format_match = format_match,
 	.init = init,
 	.receive = receive,
+	.end = end,
 	.cleanup = cleanup,
 };

src/input/wav.c

@@ -235,40 +235,18 @@ static void send_chunk(const struct sr_input *in, int offset, int num_samples)
 	sr_session_send(in->sdi, &packet);
 }
 
-static int receive(struct sr_input *in, GString *buf)
+static int process_buffer(struct sr_input *in)
 {
+	struct context *inc;
 	struct sr_datafeed_packet packet;
 	struct sr_datafeed_meta meta;
 	struct sr_channel *ch;
 	struct sr_config *src;
-	struct context *inc;
 	int offset, chunk_samples, total_samples, processed, max_chunk_samples;
-	int num_samples, ret, i;
+	int num_samples, i;
 	char channelname[8];
 
-	g_string_append_len(in->buf, buf->str, buf->len);
-
-	if (in->buf->len < MIN_DATA_CHUNK_OFFSET) {
-		/*
-		 * Don't even try until there's enough room
-		 * for the data segment to start.
-		 */
-		return SR_OK;
-	}
-
 	inc = in->priv;
-	if (!in->sdi_ready) {
-		if ((ret = parse_wav_header(in->buf, inc)) == SR_ERR_NA)
-			/* Not enough data yet. */
-			return SR_OK;
-		else if (ret != SR_OK)
-			return ret;
-
-		/* sdi is ready, notify frontend. */
-		in->sdi_ready = TRUE;
-		return SR_OK;
-	}
-
 	if (!inc->started) {
 		for (i = 0; i < inc->num_channels; i++) {
 			snprintf(channelname, 8, "CH%d", i + 1);
@@ -330,19 +308,57 @@ static int receive(struct sr_input *in, GString *buf)
 	return SR_OK;
 }
 
-static int cleanup(struct sr_input *in)
+static int receive(struct sr_input *in, GString *buf)
+{
+	struct context *inc;
+	int ret;
+
+	g_string_append_len(in->buf, buf->str, buf->len);
+
+	if (in->buf->len < MIN_DATA_CHUNK_OFFSET) {
+		/*
+		 * Don't even try until there's enough room
+		 * for the data segment to start.
+		 */
+		return SR_OK;
+	}
+
+	inc = in->priv;
+	if (!in->sdi_ready) {
+		if ((ret = parse_wav_header(in->buf, inc)) == SR_ERR_NA)
+			/* Not enough data yet. */
+			return SR_OK;
+		else if (ret != SR_OK)
+			return ret;
+
+		/* sdi is ready, notify frontend. */
+		in->sdi_ready = TRUE;
+		return SR_OK;
+	}
+
+	ret = process_buffer(in);
+
+	return SR_OK;
+}
+
+static int end(struct sr_input *in)
 {
 	struct sr_datafeed_packet packet;
 	struct context *inc;
+	int ret;
+
+	if (in->sdi_ready)
+		ret = process_buffer(in);
+	else
+		ret = SR_OK;
 
 	inc = in->priv;
 	if (inc->started) {
-		/* End of stream. */
 		packet.type = SR_DF_END;
 		sr_session_send(in->sdi, &packet);
 	}
 
-	return SR_OK;
+	return ret;
 }
 
 SR_PRIV struct sr_input_module input_wav = {
@@ -353,6 +369,6 @@ SR_PRIV struct sr_input_module input_wav = {
 	.format_match = format_match,
 	.init = init,
 	.receive = receive,
-	.cleanup = cleanup,
+	.end = end,
 };
 

src/libsigrok-internal.h

@@ -309,6 +309,8 @@ struct sr_input_module {
 	 */
 	int (*receive) (struct sr_input *in, GString *buf);
 
+	int (*end) (struct sr_input *in);
+
 	/**
 	 * This function is called after the caller is finished using
 	 * the input module, and can be used to free any internal