[aravis] gvcp: avoid 0 for packet_count, as it is an error value.

[Emmanuel Pacaud <emmanuel src gnome org>]

commit 2e16eb6c2c25bd886c92a42328b3269517ef6d25
Author: Emmanuel Pacaud <emmanuel gnome org>
Date:   Mon Jul 4 16:45:43 2011 +0200

    gvcp: avoid 0 for packet_count, as it is an error value.
    
    This commit should really fix the lost of connection after a period
    of time.

 docs/reference/aravis/aravis-sections.txt |    1 +
 src/arvgvcp.h                             |    9 +++++++++
 src/arvgvdevice.c                         |   14 +++++++++-----
 src/arvgvstream.c                         |    6 ++++--
 4 files changed, 23 insertions(+), 7 deletions(-)
---
diff --git a/docs/reference/aravis/aravis-sections.txt b/docs/reference/aravis/aravis-sections.txt
index b6afe16..4b5dbb6 100644
--- a/docs/reference/aravis/aravis-sections.txt
+++ b/docs/reference/aravis/aravis-sections.txt
@@ -802,6 +802,7 @@ arv_gvcp_packet_new_discovery_ack
 arv_gvcp_packet_new_packet_resend_cmd
 arv_gvcp_packet_to_string
 arv_gvcp_packet_debug
+arv_gvcp_next_packet_count
 <SUBSECTION Private>
 ARV_GVBS_CONTROL_CHANNEL_PRIVILEGE_CONTROL
 ARV_GVBS_CONTROL_CHANNEL_PRIVILEGE_EXCLUSIVE
diff --git a/src/arvgvcp.h b/src/arvgvcp.h
index b195437..1467cb8 100644
--- a/src/arvgvcp.h
+++ b/src/arvgvcp.h
@@ -313,6 +313,15 @@ arv_gvcp_packet_get_write_register_cmd_infos (const ArvGvcpPacket *packet, guint
 		*value = g_ntohl (*((guint32 *) ((char *) packet + sizeof (ArvGvcpPacket) + sizeof (guint32))));
 }
 
+static inline guint16
+arv_gvcp_next_packet_count (guint16 packet_count)
+{
+	/* packet_count == 0 is an error value */
+	if (packet_count == 0xffff)
+		return 1;
+	return packet_count++;
+}
+
 G_END_DECLS
 
 #endif
diff --git a/src/arvgvdevice.c b/src/arvgvdevice.c
index 96a6066..495b299 100644
--- a/src/arvgvdevice.c
+++ b/src/arvgvdevice.c
@@ -93,7 +93,8 @@ _read_memory (ArvGvDeviceIOData *io_data, guint32 address, guint32 size, void *b
 						      0, &packet_size);
 
 	do {
-		arv_gvcp_packet_set_packet_count (packet, ++io_data->packet_count);
+		io_data->packet_count = arv_gvcp_next_packet_count (io_data->packet_count);
+		arv_gvcp_packet_set_packet_count (packet, io_data->packet_count);
 
 		arv_gvcp_packet_debug (packet, ARV_DEBUG_LEVEL_LOG);
 
@@ -157,7 +158,8 @@ _write_memory (ArvGvDeviceIOData *io_data, guint32 address, guint32 size, void *
 	memcpy (arv_gvcp_packet_get_write_memory_cmd_data (packet), buffer, size);
 
 	do {
-		arv_gvcp_packet_set_packet_count (packet, ++io_data->packet_count);
+		io_data->packet_count = arv_gvcp_next_packet_count (io_data->packet_count);
+		arv_gvcp_packet_set_packet_count (packet, io_data->packet_count);
 
 		arv_gvcp_packet_debug (packet, ARV_DEBUG_LEVEL_LOG);
 
@@ -215,7 +217,8 @@ _read_register (ArvGvDeviceIOData *io_data, guint32 address, guint32 *value_plac
 	packet = arv_gvcp_packet_new_read_register_cmd (address, 0, &packet_size);
 
 	do {
-		arv_gvcp_packet_set_packet_count (packet, ++io_data->packet_count);
+		io_data->packet_count = arv_gvcp_next_packet_count (io_data->packet_count);
+		arv_gvcp_packet_set_packet_count (packet, io_data->packet_count);
 
 		arv_gvcp_packet_debug (packet, ARV_DEBUG_LEVEL_LOG);
 
@@ -277,7 +280,8 @@ _write_register (ArvGvDeviceIOData *io_data, guint32 address, guint32 value)
 	packet = arv_gvcp_packet_new_write_register_cmd (address, value, io_data->packet_count, &packet_size);
 
 	do {
-		arv_gvcp_packet_set_packet_count (packet, ++io_data->packet_count);
+		io_data->packet_count = arv_gvcp_next_packet_count (io_data->packet_count);
+		arv_gvcp_packet_set_packet_count (packet, io_data->packet_count);
 
 		arv_gvcp_packet_debug (packet, ARV_DEBUG_LEVEL_LOG);
 
@@ -688,7 +692,7 @@ arv_gv_device_new (GInetAddress *interface_address, GInetAddress *device_address
 	io_data = g_new0 (ArvGvDeviceIOData, 1);
 
 	io_data->mutex = g_mutex_new ();
-	io_data->packet_count = 0;
+	io_data->packet_count = 65300; /* Start near the end of the circular counter */
 
 	io_data->interface_address = g_inet_socket_address_new (interface_address, 0);
 	io_data->device_address = g_inet_socket_address_new (device_address, ARV_GVCP_PORT);
diff --git a/src/arvgvstream.c b/src/arvgvstream.c
index 0965a8b..007af54 100644
--- a/src/arvgvstream.c
+++ b/src/arvgvstream.c
@@ -134,8 +134,10 @@ _send_packet_request (ArvGvStreamThreadData *thread_data,
 	ArvGvcpPacket *packet;
 	size_t packet_size;
 
+	thread_data->packet_count = arv_gvcp_next_packet_count (thread_data->packet_count);
+
 	packet = arv_gvcp_packet_new_packet_resend_cmd (frame_id, first_block, last_block,
-							thread_data->packet_count++, &packet_size);
+							thread_data->packet_count, &packet_size);
 
 	arv_log_stream_thread ("[GvStream::send_packet_request] frame_id = %u (%d - %d)",
 			       frame_id, first_block, last_block);
@@ -734,7 +736,7 @@ arv_gv_stream_new (GInetAddress *device_address, guint16 port,
 	thread_data->data_size = packet_size - ARV_GVSP_PACKET_PROTOCOL_OVERHEAD;
 	thread_data->cancel = FALSE;
 
-	thread_data->packet_count = 1;
+	thread_data->packet_count = 65300;
 	thread_data->last_frame_id = 0;
 
 	thread_data->n_completed_buffers = 0;