/*
* pj_ioqueue_recv()
*
* Start asynchronous recv() from the socket.
*/
PJ_DEF(pj_status_t) pj_ioqueue_recv( pj_ioqueue_key_t *key,
pj_ioqueue_op_key_t *op_key,
void *buffer,
pj_ssize_t *length,
unsigned flags )
{
struct read_operation *read_op;
PJ_ASSERT_RETURN(key && op_key && buffer && length, PJ_EINVAL);
PJ_CHECK_STACK();
/* Check if key is closing (need to do this first before accessing
* other variables, since they might have been destroyed. See ticket
* #469).
*/
if (IS_CLOSING(key))
return PJ_ECANCELLED;
read_op = (struct read_operation*)op_key;
read_op->op = PJ_IOQUEUE_OP_NONE;
/* Try to see if there's data immediately available.
*/
if ((flags & PJ_IOQUEUE_ALWAYS_ASYNC) == 0) {
pj_status_t status;
pj_ssize_t size;
size = *length;
status = pj_sock_recv(key->fd, buffer, &size, flags);
if (status == PJ_SUCCESS) {
/* Yes! Data is available! */
*length = size;
return PJ_SUCCESS;
} else {
/* If error is not EWOULDBLOCK (or EAGAIN on Linux), report
* the error to caller.
*/
if (status != PJ_STATUS_FROM_OS(PJ_BLOCKING_ERROR_VAL))
return status;
}
}
flags &= ~(PJ_IOQUEUE_ALWAYS_ASYNC);
/*
* No data is immediately available.
* Must schedule asynchronous operation to the ioqueue.
*/
read_op->op = PJ_IOQUEUE_OP_RECV;
read_op->buf = buffer;
read_op->size = *length;
read_op->flags = flags;
pj_mutex_lock(key->mutex);
pj_list_insert_before(&key->read_list, read_op);
ioqueue_add_to_set(key->ioqueue, key, READABLE_EVENT);
pj_mutex_unlock(key->mutex);
return PJ_EPENDING;
}
/*
* Initiate overlapped connect() operation (well, it's non-blocking actually,
* since there's no overlapped version of connect()).
*/
PJ_DEF(pj_status_t) pj_ioqueue_connect( pj_ioqueue_key_t *key,
const pj_sockaddr_t *addr,
int addrlen )
{
pj_status_t status;
/* check parameters. All must be specified! */
PJ_ASSERT_RETURN(key && addr && addrlen, PJ_EINVAL);
/* Check if key is closing. */
if (IS_CLOSING(key))
return PJ_ECANCELLED;
/* Check if socket has not been marked for connecting */
if (key->connecting != 0)
return PJ_EPENDING;
status = pj_sock_connect(key->fd, addr, addrlen);
if (status == PJ_SUCCESS) {
/* Connected! */
return PJ_SUCCESS;
} else {
if (status == PJ_STATUS_FROM_OS(PJ_BLOCKING_CONNECT_ERROR_VAL)) {
/* Pending! */
pj_ioqueue_lock_key(key);
/* Check again. Handle may have been closed after the previous
* check in multithreaded app. See #913
*/
if (IS_CLOSING(key)) {
pj_ioqueue_unlock_key(key);
return PJ_ECANCELLED;
}
key->connecting = PJ_TRUE;
ioqueue_add_to_set(key->ioqueue, key, WRITEABLE_EVENT);
ioqueue_add_to_set(key->ioqueue, key, EXCEPTION_EVENT);
pj_ioqueue_unlock_key(key);
return PJ_EPENDING;
} else {
/* Error! */
return status;
}
}
}
/*
* Initiate overlapped accept() operation.
*/
PJ_DEF(pj_status_t) pj_ioqueue_accept( pj_ioqueue_key_t *key,
pj_ioqueue_op_key_t *op_key,
pj_sock_t *new_sock,
pj_sockaddr_t *local,
pj_sockaddr_t *remote,
int *addrlen)
{
struct accept_operation *accept_op;
pj_status_t status;
/* check parameters. All must be specified! */
PJ_ASSERT_RETURN(key && op_key && new_sock, PJ_EINVAL);
/* Check if key is closing. */
if (IS_CLOSING(key))
return PJ_ECANCELLED;
accept_op = (struct accept_operation*)op_key;
accept_op->op = PJ_IOQUEUE_OP_NONE;
/* Fast track:
* See if there's new connection available immediately.
*/
if (pj_list_empty(&key->accept_list)) {
status = pj_sock_accept(key->fd, new_sock, remote, addrlen);
if (status == PJ_SUCCESS) {
/* Yes! New connection is available! */
if (local && addrlen) {
status = pj_sock_getsockname(*new_sock, local, addrlen);
if (status != PJ_SUCCESS) {
pj_sock_close(*new_sock);
*new_sock = PJ_INVALID_SOCKET;
return status;
}
}
return PJ_SUCCESS;
} else {
/* If error is not EWOULDBLOCK (or EAGAIN on Linux), report
* the error to caller.
*/
if (status != PJ_STATUS_FROM_OS(PJ_BLOCKING_ERROR_VAL)) {
return status;
}
}
}
/*
* No connection is available immediately.
* Schedule accept() operation to be completed when there is incoming
* connection available.
*/
accept_op->op = PJ_IOQUEUE_OP_ACCEPT;
accept_op->accept_fd = new_sock;
accept_op->rmt_addr = remote;
accept_op->addrlen= addrlen;
accept_op->local_addr = local;
pj_mutex_lock(key->mutex);
pj_list_insert_before(&key->accept_list, accept_op);
ioqueue_add_to_set(key->ioqueue, key, READABLE_EVENT);
pj_mutex_unlock(key->mutex);
return PJ_EPENDING;
}
/*
* pj_ioqueue_sendto()
*
* Start asynchronous write() to the descriptor.
*/
PJ_DEF(pj_status_t) pj_ioqueue_sendto( pj_ioqueue_key_t *key,
pj_ioqueue_op_key_t *op_key,
const void *data,
pj_ssize_t *length,
pj_uint32_t flags,
const pj_sockaddr_t *addr,
int addrlen)
{
struct write_operation *write_op;
unsigned retry;
pj_status_t status;
pj_ssize_t sent;
PJ_ASSERT_RETURN(key && op_key && data && length, PJ_EINVAL);
PJ_CHECK_STACK();
/* Check if key is closing. */
if (IS_CLOSING(key))
return PJ_ECANCELLED;
/* We can not use PJ_IOQUEUE_ALWAYS_ASYNC for socket write */
flags &= ~(PJ_IOQUEUE_ALWAYS_ASYNC);
/* Fast track:
* Try to send data immediately, only if there's no pending write!
* Note:
* We are speculating that the list is empty here without properly
* acquiring ioqueue's mutex first. This is intentional, to maximize
* performance via parallelism.
*
* This should be safe, because:
* - by convention, we require caller to make sure that the
* key is not unregistered while other threads are invoking
* an operation on the same key.
* - pj_list_empty() is safe to be invoked by multiple threads,
* even when other threads are modifying the list.
*/
if (pj_list_empty(&key->write_list)) {
/*
* See if data can be sent immediately.
*/
sent = *length;
status = pj_sock_sendto(key->fd, data, &sent, flags, addr, addrlen);
if (status == PJ_SUCCESS) {
/* Success! */
*length = sent;
return PJ_SUCCESS;
} else {
/* If error is not EWOULDBLOCK (or EAGAIN on Linux), report
* the error to caller.
*/
if (status != PJ_STATUS_FROM_OS(PJ_BLOCKING_ERROR_VAL)) {
return status;
}
status = status;
}
}
/*
* Check that address storage can hold the address parameter.
*/
PJ_ASSERT_RETURN(addrlen <= (int)sizeof(pj_sockaddr_in), PJ_EBUG);
/*
* Schedule asynchronous send.
*/
write_op = (struct write_operation*)op_key;
/* Spin if write_op has pending operation */
for (retry=0; write_op->op != 0 && retry<PENDING_RETRY; ++retry)
pj_thread_sleep(0);
/* Last chance */
if (write_op->op) {
/* Unable to send packet because there is already pending write on the
* write_op. We could not put the operation into the write_op
* because write_op already contains a pending operation! And
* we could not send the packet directly with sendto() either,
* because that will break the order of the packet. So we can
* only return error here.
*
* This could happen for example in multithreads program,
* where polling is done by one thread, while other threads are doing
* the sending only. If the polling thread runs on lower priority
* than the sending thread, then it's possible that the pending
* write flag is not cleared in-time because clearing is only done
* during polling.
*
* Aplication should specify multiple write operation keys on
* situation like this.
*/
//pj_assert(!"ioqueue: there is pending operation on this key!");
return PJ_EBUSY;
}
write_op->op = PJ_IOQUEUE_OP_SEND_TO;
write_op->buf = (char*)data;
write_op->size = *length;
write_op->written = 0;
write_op->flags = flags;
pj_memcpy(&write_op->rmt_addr, addr, addrlen);
write_op->rmt_addrlen = addrlen;
pj_mutex_lock(key->mutex);
pj_list_insert_before(&key->write_list, write_op);
ioqueue_add_to_set(key->ioqueue, key, WRITEABLE_EVENT);
pj_mutex_unlock(key->mutex);
return PJ_EPENDING;
}
/*
* pj_ioqueue_recvfrom()
*
* Start asynchronous recvfrom() from the socket.
*/
PJ_DEF(pj_status_t) pj_ioqueue_recvfrom( pj_ioqueue_key_t *key,
pj_ioqueue_op_key_t *op_key,
void *buffer,
pj_ssize_t *length,
unsigned flags,
pj_sockaddr_t *addr,
int *addrlen)
{
struct read_operation *read_op;
PJ_ASSERT_RETURN(key && op_key && buffer && length, PJ_EINVAL);
PJ_CHECK_STACK();
/* Check if key is closing. */
if (IS_CLOSING(key))
return PJ_ECANCELLED;
read_op = (struct read_operation*)op_key;
read_op->op = PJ_IOQUEUE_OP_NONE;
/* Try to see if there's data immediately available.
*/
if ((flags & PJ_IOQUEUE_ALWAYS_ASYNC) == 0) {
pj_status_t status;
pj_ssize_t size;
size = *length;
status = pj_sock_recvfrom(key->fd, buffer, &size, flags,
addr, addrlen);
if (status == PJ_SUCCESS) {
/* Yes! Data is available! */
*length = size;
return PJ_SUCCESS;
} else {
/* If error is not EWOULDBLOCK (or EAGAIN on Linux), report
* the error to caller.
*/
if (status != PJ_STATUS_FROM_OS(PJ_BLOCKING_ERROR_VAL))
return status;
}
}
flags &= ~(PJ_IOQUEUE_ALWAYS_ASYNC);
/*
* No data is immediately available.
* Must schedule asynchronous operation to the ioqueue.
*/
read_op->op = PJ_IOQUEUE_OP_RECV_FROM;
read_op->buf = buffer;
read_op->size = *length;
read_op->flags = flags;
read_op->rmt_addr = addr;
read_op->rmt_addrlen = addrlen;
pj_ioqueue_lock_key(key);
/* Check again. Handle may have been closed after the previous check
* in multithreaded app. If we add bad handle to the set it will
* corrupt the ioqueue set. See #913
*/
if (IS_CLOSING(key)) {
pj_ioqueue_unlock_key(key);
return PJ_ECANCELLED;
}
pj_list_insert_before(&key->read_list, read_op);
ioqueue_add_to_set(key->ioqueue, key, READABLE_EVENT);
pj_ioqueue_unlock_key(key);
return PJ_EPENDING;
}