1 files changed, 141 insertions, 0 deletions
diff --git a/lib/libdvben50221/en50221_app_teletext.c b/lib/libdvben50221/en50221_app_teletext.c
new file mode 100644
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--- /dev/null
+++ b/lib/libdvben50221/en50221_app_teletext.c
@@ -0,0 +1,141 @@
+/*
+    en50221 encoder An implementation for libdvb
+    an implementation for the en50221 transport layer
+
+    Copyright (C) 2004, 2005 Manu Abraham <abraham.manu@gmail.com>
+    Copyright (C) 2005 Julian Scheel (julian at jusst dot de)
+    Copyright (C) 2006 Andrew de Quincey (adq_dvb@lidskialf.net)
+
+    This library is free software; you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as
+    published by the Free Software Foundation; either version 2.1 of
+    the License, or (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+*/
+
+#include <string.h>
+#include <libdvbmisc/dvbmisc.h>
+#include <pthread.h>
+#include "en50221_app_teletext.h"
+#include "en50221_app_tags.h"
+#include "asn_1.h"
+
+struct en50221_app_teletext {
+	struct en50221_app_send_functions *funcs;
+
+	en50221_app_teletext_callback callback;
+	void *callback_arg;
+
+	pthread_mutex_t lock;
+};
+
+static int en50221_app_teletext_parse_ebu(struct en50221_app_teletext *teletext,
+					  uint8_t slot_id,
+					  uint16_t session_number,
+					  uint8_t * data,
+					  uint32_t data_length);
+
+
+
+struct en50221_app_teletext *
+	en50221_app_teletext_create(struct en50221_app_send_functions *funcs)
+{
+	struct en50221_app_teletext *teletext = NULL;
+
+	// create structure and set it up
+	teletext = malloc(sizeof(struct en50221_app_teletext));
+	if (teletext == NULL) {
+		return NULL;
+	}
+	teletext->funcs = funcs;
+	teletext->callback = NULL;
+
+	pthread_mutex_init(&teletext->lock, NULL);
+
+	// done
+	return teletext;
+}
+
+void en50221_app_teletext_destroy(struct en50221_app_teletext *teletext)
+{
+	pthread_mutex_destroy(&teletext->lock);
+	free(teletext);
+}
+
+void en50221_app_teletext_register_callback(struct en50221_app_teletext *teletext,
+					    en50221_app_teletext_callback callback, void *arg)
+{
+	pthread_mutex_lock(&teletext->lock);
+	teletext->callback = callback;
+	teletext->callback_arg = arg;
+	pthread_mutex_unlock(&teletext->lock);
+}
+
+int en50221_app_teletext_message(struct en50221_app_teletext *teletext,
+				 uint8_t slot_id,
+				 uint16_t session_number,
+				 uint32_t resource_id,
+				 uint8_t * data, uint32_t data_length)
+{
+	(void) resource_id;
+
+	// get the tag
+	if (data_length < 3) {
+		print(LOG_LEVEL, ERROR, 1, "Received short data\n");
+		return -1;
+	}
+	uint32_t tag = (data[0] << 16) | (data[1] << 8) | data[2];
+
+	switch (tag) {
+	case TAG_TELETEXT_EBU:
+		return en50221_app_teletext_parse_ebu(teletext, slot_id,
+						      session_number,
+						      data + 3,
+						      data_length - 3);
+	}
+
+	print(LOG_LEVEL, ERROR, 1, "Received unexpected tag %x\n", tag);
+	return -1;
+}
+
+
+static int en50221_app_teletext_parse_ebu(struct en50221_app_teletext *teletext,
+					  uint8_t slot_id,
+					  uint16_t session_number,
+					  uint8_t *data,
+					  uint32_t data_length)
+{
+	// first of all, decode the length field
+	uint16_t asn_data_length;
+	int length_field_len;
+	if ((length_field_len = asn_1_decode(&asn_data_length, data, data_length)) < 0) {
+		print(LOG_LEVEL, ERROR, 1, "ASN.1 decode error\n");
+		return -1;
+	}
+
+	// check it
+	if (asn_data_length > (data_length - length_field_len)) {
+		print(LOG_LEVEL, ERROR, 1, "Received short data\n");
+		return -1;
+	}
+	uint8_t *teletext_data = data + length_field_len;
+
+	// tell the app
+	pthread_mutex_lock(&teletext->lock);
+	en50221_app_teletext_callback cb = teletext->callback;
+	void *cb_arg = teletext->callback_arg;
+	pthread_mutex_unlock(&teletext->lock);
+	if (cb) {
+		return cb(cb_arg, slot_id, session_number, teletext_data,
+			  asn_data_length);
+	}
+	return 0;
+}