/*
* call-seq:
* socket.getsockopt(option)
*
* Retrieves the value of the specified 0MQ socket option.
*
* The following options can be retrievesd with the getsockopt() function:
*
* == ZMQ::RCVMORE: More message parts to follow
* The ZMQ::RCVMORE option shall return a boolean value indicating if the
* multi-part message currently being read from the specified socket has more
* message parts to follow. If there are no message parts to follow or if the
* message currently being read is not a multi-part message a value of false
* shall be returned. Otherwise, a value of true shall be returned.
*
* Refer to send() and recv() for a detailed description of sending/receiving
* multi-part messages.
*
* [Option value type] Boolean
* [Option value unit] N/A
* [Default value] N/A
* [Applicable socket types] all
*
* == ZMQ::HWM: Retrieve high water mark
* The ZMQ::HWM option shall retrieve the high water mark for the specified
* _socket_. The high water mark is a hard limit on the maximum number of
* outstanding messages 0MQ shall queue in memory for any single peer that the
* specified _socket_ is communicating with.
*
* If this limit has been reached the socket shall enter an exceptional state
* and depending on the socket type, 0MQ shall take appropriate action such as
* blocking or dropping sent messages. Refer to the individual socket
* descriptions in ZMQ::Socket for details on the exact action taken for each
* socket type.
*
* The default ZMQ::HWM value of zero means "no limit".
*
* [Option value type] Integer
* [Option value unit] messages
* [Default value] 0
* [Applicable socket types] all
*
* == ZMQ::SWAP: Retrieve disk offload size
* The ZMQ::SWAP option shall retrieve the disk offload (swap) size for the
* specified _socket_. A socket which has ZMQ::SWAP set to a non-zero value may
* exceed it’s high water mark; in this case outstanding messages shall be
* offloaded to storage on disk rather than held in memory.
*
* The value of ZMQ::SWAP defines the maximum size of the swap space in bytes.
*
* [Option value type] Integer
* [Option value unit] bytes
* [Default value] 0
* [Applicable socket types] all
*
* == ZMQ::AFFINITY: Retrieve I/O thread affinity
* The ZMQ::AFFINITY option shall retrieve the I/O thread affinity for newly
* created connections on the specified _socket_.
*
* Affinity determines which threads from the 0MQ I/O thread pool associated
* with the socket’s _context_ shall handle newly created connections. A value of
* zero specifies no affinity, meaning that work shall be distributed fairly
* among all 0MQ I/O threads in the thread pool. For non-zero values, the lowest
* bit corresponds to thread 1, second lowest bit to thread 2 and so on. For
* example, a value of 3 specifies that subsequent connections on _socket_ shall
* be handled exclusively by I/O threads 1 and 2.
*
* See also ZMQ::Context#new for details on allocating the number of
* I/O threads for a specific _context_.
*
* [Option value type] Integer
* [Option value unit] N/A (bitmap)
* [Default value] 0
* [Applicable socket types] all
*
* == ZMQ::IDENTITY: Retrieve socket identity
* The ZMQ::IDENTITY option shall retrieve the identity of the specified _socket_.
* Socket identity determines if existing 0MQ infastructure (<em>message queues</em>,
* <em>forwarding devices</em>) shall be identified with a specific application and
* persist across multiple runs of the application.
*
* If the socket has no identity, each run of an application is completely
* separate from other runs. However, with identity set the socket shall re-use
* any existing 0MQ infrastructure configured by the previous run(s). Thus the
* application may receive messages that were sent in the meantime, <em>message
* queue</em> limits shall be shared with previous run(s) and so on.
*
* Identity can be at least one byte and at most 255 bytes long. Identities
* starting with binary zero are reserved for use by 0MQ infrastructure.
*
* [Option value type] String
* [Option value unit] N/A
* [Default value] nil
* [Applicable socket types] all
*
* == ZMQ::RATE: Retrieve multicast data rate
*
* The ZMQ::Rate option shall retrieve the maximum send or receive data
* rate for multicast transports using the specified _socket_.
*
* [Option value type] Integer
* [Option value unit] kilobits per second
* [Default value] 100
* [Applicable socket types] all, when using multicast transports
*
* == ZMQ::RECOVERY_IVL: Get multicast recovery interval
*
* The ZMQ::RECOVERY_IVL option shall retrieve the recovery interval for
* multicast transports using the specified _socket_. The recovery interval
* determines the maximum time in seconds that a receiver can be absent from a
* multicast group before unrecoverable data loss will occur.
*
* [Option value type] Integer
* [Option value unit] seconds
* [Default value] 10
* [Applicable socket types] all, when using multicast transports
*
* == ZMQ::MCAST_LOOP: Control multicast loopback
* The ZMQ::MCAST_LOOP option controls whether data sent via multicast transports
* can also be received by the sending host via loopback. A value of zero
* indicates that the loopback functionality is disabled, while the default
* value of 1 indicates that the loopback functionality is enabled. Leaving
* multicast loopback enabled when it is not required can have a negative impact
* on performance. Where possible, disable ZMQ::MCAST_LOOP in production
* environments.
*
* [Option value type] Boolean
* [Option value unit] N/A
* [Default value] true
* [Applicable socket types] all, when using multicast transports
*
* == ZMQ::SNDBUF: Retrieve kernel transmit buffer size
* The ZMQ::SNDBUF option shall retrieve the underlying kernel transmit buffer
* size for the specified _socket_. A value of zero means that the OS default is
* in effect. For details refer to your operating system documentation for the
* SO_SNDBUF socket option.
*
* [Option value type] Integer
* [Option value unit] bytes
* [Default value] 0
* [Applicable socket types] all
*
* == ZMQ::RCVBUF: Retrieve kernel receive buffer size
* The ZMQ::RCVBUF option shall retrieve the underlying kernel receive buffer
* size for the specified _socket_. A value of zero means that the OS default is
* in effect. For details refer to your operating system documentation for the
* SO_RCVBUF socket option.
*
* [Option value type] Integer
* [Option value unit] bytes
* [Default value] 0
* [Applicable socket types] all
*
*/
static VALUE socket_getsockopt (VALUE self_, VALUE option_)
{
int rc = 0;
VALUE retval;
void * s;
Data_Get_Struct (self_, void, s);
Check_Socket (s);
switch (NUM2INT (option_)) {
case ZMQ_RCVMORE:
case ZMQ_HWM:
case ZMQ_SWAP:
case ZMQ_AFFINITY:
case ZMQ_RATE:
case ZMQ_RECOVERY_IVL:
case ZMQ_MCAST_LOOP:
case ZMQ_SNDBUF:
case ZMQ_RCVBUF:
{
int64_t optval;
size_t optvalsize = sizeof(optval);
rc = zmq_getsockopt (s, NUM2INT (option_), (void *)&optval,
&optvalsize);
if (rc != 0) {
rb_raise (rb_eRuntimeError, "%s", zmq_strerror (zmq_errno ()));
return Qnil;
}
if (NUM2INT (option_) == ZMQ_RCVMORE)
retval = optval ? Qtrue : Qfalse;
else
retval = INT2NUM (optval);
}
break;
case ZMQ_IDENTITY:
{
char identity[255];
size_t optvalsize = sizeof (identity);
rc = zmq_getsockopt (s, NUM2INT (option_), (void *)identity,
&optvalsize);
if (rc != 0) {
rb_raise (rb_eRuntimeError, "%s", zmq_strerror (zmq_errno ()));
return Qnil;
}
if (optvalsize > sizeof (identity))
optvalsize = sizeof (identity);
retval = rb_str_new (identity, optvalsize);
}
break;
default:
rb_raise (rb_eRuntimeError, "%s", zmq_strerror (EINVAL));
return Qnil;
}
return retval;
}