/**
* Continue an outstanding write for a particular socket
* @param socket that socket
* @return completion code
*/
int Socket_continueWrite(int socket)
{
int rc = 0;
pending_writes* pw;
unsigned long curbuflen = 0L, /* cumulative total of buffer lengths */
bytes;
int curbuf = -1, i;
iobuf iovecs1[5];
FUNC_ENTRY;
pw = SocketBuffer_getWrite(socket);
#if defined(OPENSSL)
if (pw->ssl)
{
rc = SSLSocket_continueWrite(pw);
goto exit;
}
#endif
for (i = 0; i < pw->count; ++i)
{
if (pw->bytes <= curbuflen)
{ /* if previously written length is less than the buffer we are currently looking at,
add the whole buffer */
iovecs1[++curbuf].iov_len = pw->iovecs[i].iov_len;
iovecs1[curbuf].iov_base = pw->iovecs[i].iov_base;
}
else if (pw->bytes < curbuflen + pw->iovecs[i].iov_len)
{ /* if previously written length is in the middle of the buffer we are currently looking at,
add some of the buffer */
int offset = pw->bytes - curbuflen;
iovecs1[++curbuf].iov_len = pw->iovecs[i].iov_len - offset;
iovecs1[curbuf].iov_base = pw->iovecs[i].iov_base + offset;
break;
}
curbuflen += pw->iovecs[i].iov_len;
}
if ((rc = Socket_writev(socket, iovecs1, curbuf+1, &bytes)) != SOCKET_ERROR)
{
pw->bytes += bytes;
if ((rc = (pw->bytes == pw->total)))
{ /* topic and payload buffers are freed elsewhere, when all references to them have been removed */
free(pw->iovecs[0].iov_base);
free(pw->iovecs[1].iov_base);
if (pw->count == 5)
free(pw->iovecs[3].iov_base);
Log(TRACE_MIN, -1, "ContinueWrite: partial write now complete for socket %d", socket);
}
else
Log(TRACE_MIN, -1, "ContinueWrite wrote +%lu bytes on socket %d", bytes, socket);
}
#if defined(OPENSSL)
exit:
#endif
FUNC_EXIT_RC(rc);
return rc;
}
int MQTTClient_publish(MQTTClient handle, const char* topicName, int payloadlen, void* payload,
int qos, int retained, MQTTClient_deliveryToken* deliveryToken)
{
int rc = MQTTCLIENT_SUCCESS;
MQTTClients* m = handle;
Messages* msg = NULL;
Publish* p = NULL;
int blocked = 0;
int msgid = 0;
FUNC_ENTRY;
Thread_lock_mutex(mqttclient_mutex);
if (m == NULL || m->c == NULL)
rc = MQTTCLIENT_FAILURE;
else if (m->c->connected == 0)
rc = MQTTCLIENT_DISCONNECTED;
else if (!UTF8_validateString(topicName))
rc = MQTTCLIENT_BAD_UTF8_STRING;
if (rc != MQTTCLIENT_SUCCESS)
goto exit;
/* If outbound queue is full, block until it is not */
while (m->c->outboundMsgs->count >= m->c->maxInflightMessages ||
Socket_noPendingWrites(m->c->net.socket) == 0) /* wait until the socket is free of large packets being written */
{
if (blocked == 0)
{
blocked = 1;
Log(TRACE_MIN, -1, "Blocking publish on queue full for client %s", m->c->clientID);
}
Thread_unlock_mutex(mqttclient_mutex);
MQTTClient_yield();
Thread_lock_mutex(mqttclient_mutex);
if (m->c->connected == 0)
{
rc = MQTTCLIENT_FAILURE;
goto exit;
}
}
if (blocked == 1)
Log(TRACE_MIN, -1, "Resuming publish now queue not full for client %s", m->c->clientID);
if (qos > 0 && (msgid = MQTTProtocol_assignMsgId(m->c)) == 0)
{ /* this should never happen as we've waited for spaces in the queue */
rc = MQTTCLIENT_MAX_MESSAGES_INFLIGHT;
goto exit;
}
p = malloc(sizeof(Publish));
p->payload = payload;
p->payloadlen = payloadlen;
p->topic = (char*)topicName;
p->msgId = msgid;
rc = MQTTProtocol_startPublish(m->c, p, qos, retained, &msg);
/* If the packet was partially written to the socket, wait for it to complete.
* However, if the client is disconnected during this time and qos is not 0, still return success, as
* the packet has already been written to persistence and assigned a message id so will
* be sent when the client next connects.
*/
if (rc == TCPSOCKET_INTERRUPTED)
{
while (m->c->connected == 1 && SocketBuffer_getWrite(m->c->net.socket))
{
Thread_unlock_mutex(mqttclient_mutex);
MQTTClient_yield();
Thread_lock_mutex(mqttclient_mutex);
}
rc = (qos > 0 || m->c->connected == 1) ? MQTTCLIENT_SUCCESS : MQTTCLIENT_FAILURE;
}
if (deliveryToken && qos > 0)
*deliveryToken = msg->msgid;
free(p);
if (rc == SOCKET_ERROR)
{
Thread_unlock_mutex(mqttclient_mutex);
MQTTClient_disconnect_internal(handle, 0);
Thread_lock_mutex(mqttclient_mutex);
/* Return success for qos > 0 as the send will be retried automatically */
rc = (qos > 0) ? MQTTCLIENT_SUCCESS : MQTTCLIENT_FAILURE;
}
exit:
Thread_unlock_mutex(mqttclient_mutex);
FUNC_EXIT_RC(rc);
return rc;
}
