public static bool exists(string serviceName, bool logFailureReason = false)
{
string mappedName = Names.Resolve(serviceName);
string host = "";
int port = 0;
if (ServiceManager.Instance.LookUpService(mappedName, ref host, ref port))
{
var transport = new TcpTransport();
if (transport.connect(host, port))
{
var m = new Dictionary <string, string>
{
{ "probe", "1" },
{ "md5sum", "*" },
{ "callerid", ThisNode.Name },
{ "service", mappedName }
};
var h = new Header();
h.Write(m, out byte[] headerbuf, out int size);
byte[] sizebuf = BitConverter.GetBytes(size);
transport.write(sizebuf, 0, sizebuf.Length);
transport.write(headerbuf, 0, size);
return(true);
}
if (logFailureReason)
{
ROS.Info()($"[{ThisNode.Name}] waitForService: Service[{mappedName}] could not connect to host [{host}:{port}], waiting...");
}
}
else if (logFailureReason)
{
ROS.Info()($"[{ThisNode.Name}] waitForService: Service[{mappedName}] has not been advertised, waiting...");
}
return(false);
}
private void writeTransport()
{
lock ( writing )
{
if (dropped)
{
return;
}
bool can_write_more = true;
while (write_callback != null && can_write_more && !dropped)
{
int to_write = write_size - write_sent;
int bytes_sent = transport.write(write_buffer, write_sent, to_write);
if (bytes_sent <= 0)
{
return;
}
write_sent += (int)bytes_sent;
if (bytes_sent < write_size - write_sent)
{
can_write_more = false;
}
if (write_sent == write_size && !dropped)
{
WriteFinishedFunc callback = write_callback;
write_callback = null;
write_buffer = null;
write_sent = 0;
write_size = 0;
if (!callback(this))
{
ROS.Error()($"[{ThisNode.Name}] Failed to invoke {callback.GetMethodInfo().Name}");
}
}
}
}
}
