/**
* See if more data needs to be written from a previous call to netconn_write.
* Called initially from lwip_netconn_do_write. If the first call can't send all data
* (because of low memory or empty send-buffer), this function is called again
* from sent_tcp() or poll_tcp() to send more data. If all data is sent, the
* blocking application thread (waiting in netconn_write) is released.
*
* @param conn netconn (that is currently in state NETCONN_WRITE) to process
* @return ERR_OK
* ERR_MEM if LWIP_TCPIP_CORE_LOCKING=1 and sending hasn't yet finished
*/
static err_t
lwip_netconn_do_writemore(struct netconn *conn)
{
err_t err;
void *dataptr;
u16_t len, available;
u8_t write_finished = 0;
size_t diff;
u8_t dontblock = netconn_is_nonblocking(conn) ||
(conn->current_msg->msg.w.apiflags & NETCONN_DONTBLOCK);
u8_t apiflags = conn->current_msg->msg.w.apiflags;
LWIP_ASSERT("conn != NULL", conn != NULL);
LWIP_ASSERT("conn->state == NETCONN_WRITE", (conn->state == NETCONN_WRITE));
LWIP_ASSERT("conn->current_msg != NULL", conn->current_msg != NULL);
LWIP_ASSERT("conn->pcb.tcp != NULL", conn->pcb.tcp != NULL);
LWIP_ASSERT("conn->write_offset < conn->current_msg->msg.w.len",
conn->write_offset < conn->current_msg->msg.w.len);
#if LWIP_SO_SNDTIMEO
if ((conn->send_timeout != 0) &&
((s32_t)(sys_now() - conn->current_msg->msg.w.time_started) >= conn->send_timeout)) {
write_finished = 1;
if (conn->write_offset == 0) {
/* nothing has been written */
err = ERR_WOULDBLOCK;
conn->current_msg->msg.w.len = 0;
} else {
/* partial write */
err = ERR_OK;
conn->current_msg->msg.w.len = conn->write_offset;
}
} else
#endif /* LWIP_SO_SNDTIMEO */
{
dataptr = (u8_t*)conn->current_msg->msg.w.dataptr + conn->write_offset;
diff = conn->current_msg->msg.w.len - conn->write_offset;
if (diff > 0xffffUL) { /* max_u16_t */
len = 0xffff;
#if LWIP_TCPIP_CORE_LOCKING
conn->flags |= NETCONN_FLAG_WRITE_DELAYED;
#endif
apiflags |= TCP_WRITE_FLAG_MORE;
} else {
len = (u16_t)diff;
}
available = tcp_sndbuf(conn->pcb.tcp);
if (available < len) {
/* don't try to write more than sendbuf */
len = available;
if (dontblock){
if (!len) {
err = ERR_WOULDBLOCK;
goto err_mem;
}
} else {
#if LWIP_TCPIP_CORE_LOCKING
conn->flags |= NETCONN_FLAG_WRITE_DELAYED;
#endif
apiflags |= TCP_WRITE_FLAG_MORE;
}
}
LWIP_ASSERT("lwip_netconn_do_writemore: invalid length!", ((conn->write_offset + len) <= conn->current_msg->msg.w.len));
err = tcp_write(conn->pcb.tcp, dataptr, len, apiflags);
/* if OK or memory error, check available space */
if ((err == ERR_OK) || (err == ERR_MEM)) {
err_mem:
if (dontblock && (len < conn->current_msg->msg.w.len)) {
/* non-blocking write did not write everything: mark the pcb non-writable
and let poll_tcp check writable space to mark the pcb writable again */
API_EVENT(conn, NETCONN_EVT_SENDMINUS, len);
conn->flags |= NETCONN_FLAG_CHECK_WRITESPACE;
} else if ((tcp_sndbuf(conn->pcb.tcp) <= TCP_SNDLOWAT) ||
(tcp_sndqueuelen(conn->pcb.tcp) >= TCP_SNDQUEUELOWAT)) {
/* The queued byte- or pbuf-count exceeds the configured low-water limit,
let select mark this pcb as non-writable. */
API_EVENT(conn, NETCONN_EVT_SENDMINUS, len);
}
}
if (err == ERR_OK) {
conn->write_offset += len;
if ((conn->write_offset == conn->current_msg->msg.w.len) || dontblock) {
/* return sent length */
conn->current_msg->msg.w.len = conn->write_offset;
/* everything was written */
write_finished = 1;
conn->write_offset = 0;
}
tcp_output(conn->pcb.tcp);
} else if ((err == ERR_MEM) && !dontblock) {
/* If ERR_MEM, we wait for sent_tcp or poll_tcp to be called
we do NOT return to the application thread, since ERR_MEM is
only a temporary error! */
/* tcp_write returned ERR_MEM, try tcp_output anyway */
tcp_output(conn->pcb.tcp);
#if LWIP_TCPIP_CORE_LOCKING
conn->flags |= NETCONN_FLAG_WRITE_DELAYED;
#endif
} else {
/* On errors != ERR_MEM, we don't try writing any more but return
the error to the application thread. */
write_finished = 1;
conn->current_msg->msg.w.len = 0;
}
}
if (write_finished) {
/* everything was written: set back connection state
and back to application task */
conn->current_msg->err = err;
conn->current_msg = NULL;
conn->state = NETCONN_NONE;
#if LWIP_TCPIP_CORE_LOCKING
if ((conn->flags & NETCONN_FLAG_WRITE_DELAYED) != 0)
#endif
{
sys_sem_signal(&conn->op_completed);
}
}
#if LWIP_TCPIP_CORE_LOCKING
else
return ERR_MEM;
#endif
return ERR_OK;
}
/**
* Internal helper function to close a TCP netconn: since this sometimes
* doesn't work at the first attempt, this function is called from multiple
* places.
*
* @param conn the TCP netconn to close
*/
static void
do_close_internal(struct netconn *conn)
{
err_t err;
u8_t shut, shut_rx, shut_tx, close;
LWIP_ASSERT("invalid conn", (conn != NULL));
LWIP_ASSERT("this is for tcp netconns only", (conn->type == NETCONN_TCP));
LWIP_ASSERT("conn must be in state NETCONN_CLOSE", (conn->state == NETCONN_CLOSE));
LWIP_ASSERT("pcb already closed", (conn->pcb.tcp != NULL));
LWIP_ASSERT("conn->current_msg != NULL", conn->current_msg != NULL);
shut = conn->current_msg->msg.sd.shut;
shut_rx = shut & NETCONN_SHUT_RD;
shut_tx = shut & NETCONN_SHUT_WR;
/* shutting down both ends is the same as closing */
close = shut == NETCONN_SHUT_RDWR;
/* Set back some callback pointers */
if (close) {
tcp_arg(conn->pcb.tcp, NULL);
}
if (conn->pcb.tcp->state == LISTEN) {
tcp_accept(conn->pcb.tcp, NULL);
} else {
/* some callbacks have to be reset if tcp_close is not successful */
if (shut_rx) {
tcp_recv(conn->pcb.tcp, NULL);
tcp_accept(conn->pcb.tcp, NULL);
}
if (shut_tx) {
tcp_sent(conn->pcb.tcp, NULL);
}
if (close) {
tcp_poll(conn->pcb.tcp, NULL, 4);
tcp_err(conn->pcb.tcp, NULL);
}
}
/* Try to close the connection */
if (close) {
err = tcp_close(conn->pcb.tcp);
} else {
err = tcp_shutdown(conn->pcb.tcp, shut_rx, shut_tx);
}
if (err == ERR_OK) {
/* Closing succeeded */
conn->current_msg->err = ERR_OK;
conn->current_msg = NULL;
conn->state = NETCONN_NONE;
if (close) {
/* Set back some callback pointers as conn is going away */
conn->pcb.tcp = NULL;
/* Trigger select() in socket layer. Make sure everybody notices activity
on the connection, error first! */
API_EVENT(conn, NETCONN_EVT_ERROR, 0);
}
if (shut_rx) {
API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
}
if (shut_tx) {
API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
}
/* wake up the application task */
sys_sem_signal(&conn->op_completed);
} else {
/* Closing failed, restore some of the callbacks */
/* Closing of listen pcb will never fail! */
LWIP_ASSERT("Closing a listen pcb may not fail!", (conn->pcb.tcp->state != LISTEN));
tcp_sent(conn->pcb.tcp, sent_tcp);
tcp_poll(conn->pcb.tcp, poll_tcp, 4);
tcp_err(conn->pcb.tcp, err_tcp);
tcp_arg(conn->pcb.tcp, conn);
/* don't restore recv callback: we don't want to receive any more data */
}
/* If closing didn't succeed, we get called again either
from poll_tcp or from sent_tcp */
}
/**
* Receive callback function for UDP netconns.
* Posts the packet to conn->recvmbox or deletes it on memory error.
*
* @see udp.h (struct udp_pcb.recv) for parameters
*/
static void
recv_udp(void *arg, struct udp_pcb *pcb, struct pbuf *p,
ip_addr_t *addr, u16_t port)
{
struct netbuf *buf;
struct netconn *conn;
u16_t len;
#if LWIP_SO_RCVBUF
int recv_avail;
#endif /* LWIP_SO_RCVBUF */
LWIP_UNUSED_ARG(pcb); /* only used for asserts... */
LWIP_ASSERT("recv_udp must have a pcb argument", pcb != NULL);
LWIP_ASSERT("recv_udp must have an argument", arg != NULL);
conn = (struct netconn *)arg;
LWIP_ASSERT("recv_udp: recv for wrong pcb!", conn->pcb.udp == pcb);
#if LWIP_SO_RCVBUF
SYS_ARCH_GET(conn->recv_avail, recv_avail);
if ((conn == NULL) || !sys_mbox_valid(&conn->recvmbox) ||
((recv_avail + (int)(p->tot_len)) > conn->recv_bufsize)) {
#else /* LWIP_SO_RCVBUF */
if ((conn == NULL) || !sys_mbox_valid(&conn->recvmbox)) {
#endif /* LWIP_SO_RCVBUF */
pbuf_free(p);
return;
}
buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
if (buf == NULL) {
pbuf_free(p);
return;
} else {
buf->p = p;
buf->ptr = p;
ip_addr_set(&buf->addr, addr);
buf->port = port;
#if LWIP_NETBUF_RECVINFO
{
const struct ip_hdr* iphdr = ip_current_header();
/* get the UDP header - always in the first pbuf, ensured by udp_input */
const struct udp_hdr* udphdr = (void*)(((char*)iphdr) + IPH_LEN(iphdr));
#if LWIP_CHECKSUM_ON_COPY
buf->flags = NETBUF_FLAG_DESTADDR;
#endif /* LWIP_CHECKSUM_ON_COPY */
ip_addr_set(&buf->toaddr, ip_current_dest_addr());
buf->toport_chksum = udphdr->dest;
}
#endif /* LWIP_NETBUF_RECVINFO */
}
len = p->tot_len;
if (sys_mbox_trypost(&conn->recvmbox, buf) != ERR_OK) {
netbuf_delete(buf);
return;
} else {
#if LWIP_SO_RCVBUF
SYS_ARCH_INC(conn->recv_avail, len);
#endif /* LWIP_SO_RCVBUF */
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, len);
}
}
#endif /* LWIP_UDP */
#if LWIP_TCP
/**
* Receive callback function for TCP netconns.
* Posts the packet to conn->recvmbox, but doesn't delete it on errors.
*
* @see tcp.h (struct tcp_pcb.recv) for parameters and return value
*/
static err_t
recv_tcp(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
{
struct netconn *conn;
u16_t len;
LWIP_UNUSED_ARG(pcb);
LWIP_ASSERT("recv_tcp must have a pcb argument", pcb != NULL);
LWIP_ASSERT("recv_tcp must have an argument", arg != NULL);
conn = (struct netconn *)arg;
if (conn == NULL) {
return ERR_VAL;
}
LWIP_ASSERT("recv_tcp: recv for wrong pcb!", conn->pcb.tcp == pcb);
if (!sys_mbox_valid(&conn->recvmbox)) {
/* recvmbox already deleted */
if (p != NULL) {
tcp_recved(pcb, p->tot_len);
pbuf_free(p);
}
return ERR_OK;
}
/* Unlike for UDP or RAW pcbs, don't check for available space
using recv_avail since that could break the connection
(data is already ACKed) */
/* don't overwrite fatal errors! */
NETCONN_SET_SAFE_ERR(conn, err);
if (p != NULL) {
len = p->tot_len;
} else {
len = 0;
}
if (sys_mbox_trypost(&conn->recvmbox, p) != ERR_OK) {
/* don't deallocate p: it is presented to us later again from tcp_fasttmr! */
return ERR_MEM;
} else {
#if LWIP_SO_RCVBUF
SYS_ARCH_INC(conn->recv_avail, len);
#endif /* LWIP_SO_RCVBUF */
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, len);
}
return ERR_OK;
}
/**
* Poll callback function for TCP netconns.
* Wakes up an application thread that waits for a connection to close
* or data to be sent. The application thread then takes the
* appropriate action to go on.
*
* Signals the conn->sem.
* netconn_close waits for conn->sem if closing failed.
*
* @see tcp.h (struct tcp_pcb.poll) for parameters and return value
*/
static err_t
poll_tcp(void *arg, struct tcp_pcb *pcb)
{
struct netconn *conn = (struct netconn *)arg;
LWIP_UNUSED_ARG(pcb);
LWIP_ASSERT("conn != NULL", (conn != NULL));
if (conn->state == NETCONN_WRITE) {
do_writemore(conn);
} else if (conn->state == NETCONN_CLOSE) {
do_close_internal(conn);
}
/* @todo: implement connect timeout here? */
/* Did a nonblocking write fail before? Then check available write-space. */
if (conn->flags & NETCONN_FLAG_CHECK_WRITESPACE) {
/* If the queued byte- or pbuf-count drops below the configured low-water limit,
let select mark this pcb as writable again. */
if ((conn->pcb.tcp != NULL) && (tcp_sndbuf(conn->pcb.tcp) > TCP_SNDLOWAT) &&
(tcp_sndqueuelen(conn->pcb.tcp) < TCP_SNDQUEUELOWAT)) {
conn->flags &= ~NETCONN_FLAG_CHECK_WRITESPACE;
API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
}
}
return ERR_OK;
}
/**
* Sent callback function for TCP netconns.
* Signals the conn->sem and calls API_EVENT.
* netconn_write waits for conn->sem if send buffer is low.
*
* @see tcp.h (struct tcp_pcb.sent) for parameters and return value
*/
static err_t
sent_tcp(void *arg, struct tcp_pcb *pcb, u16_t len)
{
struct netconn *conn = (struct netconn *)arg;
LWIP_UNUSED_ARG(pcb);
LWIP_ASSERT("conn != NULL", (conn != NULL));
if (conn) {
if (conn->state == NETCONN_WRITE) {
do_writemore(conn);
} else if (conn->state == NETCONN_CLOSE) {
do_close_internal(conn);
}
/* If the queued byte- or pbuf-count drops below the configured low-water limit,
let select mark this pcb as writable again. */
if ((conn->pcb.tcp != NULL) && (tcp_sndbuf(conn->pcb.tcp) > TCP_SNDLOWAT) &&
(tcp_sndqueuelen(conn->pcb.tcp) < TCP_SNDQUEUELOWAT)) {
conn->flags &= ~NETCONN_FLAG_CHECK_WRITESPACE;
API_EVENT(conn, NETCONN_EVT_SENDPLUS, len);
}
}
return ERR_OK;
}
/**
* Error callback function for TCP netconns.
* Signals conn->sem, posts to all conn mboxes and calls API_EVENT.
* The application thread has then to decide what to do.
*
* @see tcp.h (struct tcp_pcb.err) for parameters
*/
static void
err_tcp(void *arg, err_t err)
{
struct netconn *conn;
enum netconn_state old_state;
SYS_ARCH_DECL_PROTECT(lev);
conn = (struct netconn *)arg;
LWIP_ASSERT("conn != NULL", (conn != NULL));
conn->pcb.tcp = NULL;
/* no check since this is always fatal! */
SYS_ARCH_PROTECT(lev);
conn->last_err = err;
SYS_ARCH_UNPROTECT(lev);
/* reset conn->state now before waking up other threads */
old_state = conn->state;
conn->state = NETCONN_NONE;
/* Notify the user layer about a connection error. Used to signal
select. */
API_EVENT(conn, NETCONN_EVT_ERROR, 0);
/* Try to release selects pending on 'read' or 'write', too.
They will get an error if they actually try to read or write. */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
/* pass NULL-message to recvmbox to wake up pending recv */
if (sys_mbox_valid(&conn->recvmbox)) {
/* use trypost to prevent deadlock */
sys_mbox_trypost(&conn->recvmbox, NULL);
}
/* pass NULL-message to acceptmbox to wake up pending accept */
if (sys_mbox_valid(&conn->acceptmbox)) {
/* use trypost to preven deadlock */
sys_mbox_trypost(&conn->acceptmbox, NULL);
}
if ((old_state == NETCONN_WRITE) || (old_state == NETCONN_CLOSE) ||
(old_state == NETCONN_CONNECT)) {
/* calling do_writemore/do_close_internal is not necessary
since the pcb has already been deleted! */
int was_nonblocking_connect = IN_NONBLOCKING_CONNECT(conn);
SET_NONBLOCKING_CONNECT(conn, 0);
if (!was_nonblocking_connect) {
/* set error return code */
LWIP_ASSERT("conn->current_msg != NULL", conn->current_msg != NULL);
conn->current_msg->err = err;
conn->current_msg = NULL;
/* wake up the waiting task */
sys_sem_signal(&conn->op_completed);
}
} else {
LWIP_ASSERT("conn->current_msg == NULL", conn->current_msg == NULL);
}
}
/**
* Setup a tcp_pcb with the correct callback function pointers
* and their arguments.
*
* @param conn the TCP netconn to setup
*/
static void
setup_tcp(struct netconn *conn)
{
struct tcp_pcb *pcb;
pcb = conn->pcb.tcp;
tcp_arg(pcb, conn);
tcp_recv(pcb, recv_tcp);
tcp_sent(pcb, sent_tcp);
tcp_poll(pcb, poll_tcp, 4);
tcp_err(pcb, err_tcp);
}
/**
* Accept callback function for TCP netconns.
* Allocates a new netconn and posts that to conn->acceptmbox.
*
* @see tcp.h (struct tcp_pcb_listen.accept) for parameters and return value
*/
static err_t
accept_function(void *arg, struct tcp_pcb *newpcb, err_t err)
{
struct netconn *newconn;
struct netconn *conn = (struct netconn *)arg;
LWIP_DEBUGF(API_MSG_DEBUG, ("accept_function: newpcb->tate: %s\n", tcp_debug_state_str(newpcb->state)));
if (!sys_mbox_valid(&conn->acceptmbox)) {
LWIP_DEBUGF(API_MSG_DEBUG, ("accept_function: acceptmbox already deleted\n"));
return ERR_VAL;
}
/* We have to set the callback here even though
* the new socket is unknown. conn->socket is marked as -1. */
newconn = netconn_alloc(conn->type, conn->callback);
if (newconn == NULL) {
return ERR_MEM;
}
newconn->pcb.tcp = newpcb;
setup_tcp(newconn);
/* no protection: when creating the pcb, the netconn is not yet known
to the application thread */
newconn->last_err = err;
if (sys_mbox_trypost(&conn->acceptmbox, newconn) != ERR_OK) {
/* When returning != ERR_OK, the pcb is aborted in tcp_process(),
so do nothing here! */
/* remove all references to this netconn from the pcb */
struct tcp_pcb* pcb = newconn->pcb.tcp;
tcp_arg(pcb, NULL);
tcp_recv(pcb, NULL);
tcp_sent(pcb, NULL);
tcp_poll(pcb, NULL, 4);
tcp_err(pcb, NULL);
/* remove reference from to the pcb from this netconn */
newconn->pcb.tcp = NULL;
/* no need to drain since we know the recvmbox is empty. */
sys_mbox_free(&newconn->recvmbox);
sys_mbox_set_invalid(&newconn->recvmbox);
netconn_free(newconn);
return ERR_MEM;
} else {
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
}
return ERR_OK;
}
#endif /* LWIP_TCP */
/**
* Create a new pcb of a specific type.
* Called from do_newconn().
*
* @param msg the api_msg_msg describing the connection type
* @return msg->conn->err, but the return value is currently ignored
*/
static void
pcb_new(struct api_msg_msg *msg)
{
LWIP_ASSERT("pcb_new: pcb already allocated", msg->conn->pcb.tcp == NULL);
/* Allocate a PCB for this connection */
switch(NETCONNTYPE_GROUP(msg->conn->type)) {
#if LWIP_RAW
case NETCONN_RAW:
msg->conn->pcb.raw = raw_new(msg->msg.n.proto);
if(msg->conn->pcb.raw == NULL) {
msg->err = ERR_MEM;
break;
}
raw_recv(msg->conn->pcb.raw, recv_raw, msg->conn);
break;
#endif /* LWIP_RAW */
#if LWIP_UDP
case NETCONN_UDP:
msg->conn->pcb.udp = udp_new();
if(msg->conn->pcb.udp == NULL) {
msg->err = ERR_MEM;
break;
}
#if LWIP_UDPLITE
if (msg->conn->type==NETCONN_UDPLITE) {
udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_UDPLITE);
}
#endif /* LWIP_UDPLITE */
if (msg->conn->type==NETCONN_UDPNOCHKSUM) {
udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_NOCHKSUM);
}
udp_recv(msg->conn->pcb.udp, recv_udp, msg->conn);
break;
#endif /* LWIP_UDP */
#if LWIP_TCP
case NETCONN_TCP:
msg->conn->pcb.tcp = tcp_new();
if(msg->conn->pcb.tcp == NULL) {
msg->err = ERR_MEM;
break;
}
setup_tcp(msg->conn);
break;
#endif /* LWIP_TCP */
default:
/* Unsupported netconn type, e.g. protocol disabled */
msg->err = ERR_VAL;
break;
}
}
/**
* See if more data needs to be written from a previous call to netconn_write.
* Called initially from do_write. If the first call can't send all data
* (because of low memory or empty send-buffer), this function is called again
* from sent_tcp() or poll_tcp() to send more data. If all data is sent, the
* blocking application thread (waiting in netconn_write) is released.
*
* @param conn netconn (that is currently in state NETCONN_WRITE) to process
* @return ERR_OK
* ERR_MEM if LWIP_TCPIP_CORE_LOCKING=1 and sending hasn't yet finished
*/
static err_t
do_writemore(struct netconn *conn)
{
err_t err;
void *dataptr;
u16_t len, available;
u8_t write_finished = 0;
size_t diff;
LWIP_ASSERT("conn->state == NETCONN_WRITE", (conn->state == NETCONN_WRITE));
dataptr = (u8_t*)conn->write_msg->msg.w.dataptr + conn->write_offset;
diff = conn->write_msg->msg.w.len - conn->write_offset;
if (diff > 0xffffUL) { /* max_u16_t */
len = 0xffff;
#if LWIP_TCPIP_CORE_LOCKING
conn->write_delayed = 1;
#endif
} else {
len = (u16_t)diff;
}
available = tcp_sndbuf(conn->pcb.tcp);
if (available < len) {
/* don't try to write more than sendbuf */
len = available;
#if LWIP_TCPIP_CORE_LOCKING
conn->write_delayed = 1;
#endif
}
err = tcp_write(conn->pcb.tcp, dataptr, len, conn->write_msg->msg.w.apiflags);
LWIP_ASSERT("do_writemore: invalid length!", ((conn->write_offset + len) <= conn->write_msg->msg.w.len));
if (err == ERR_OK) {
conn->write_offset += len;
if (conn->write_offset == conn->write_msg->msg.w.len) {
/* everything was written */
write_finished = 1;
conn->write_msg = NULL;
conn->write_offset = 0;
/* API_EVENT might call tcp_tmr, so reset conn->state now */
conn->state = NETCONN_NONE;
}
err = tcp_output_nagle(conn->pcb.tcp);
conn->err = err;
if ((err == ERR_OK) && (tcp_sndbuf(conn->pcb.tcp) <= TCP_SNDLOWAT)) {
API_EVENT(conn, NETCONN_EVT_SENDMINUS, len);
}
} else if (err == ERR_MEM) {
/* If ERR_MEM, we wait for sent_tcp or poll_tcp to be called
we do NOT return to the application thread, since ERR_MEM is
only a temporary error! */
/* tcp_enqueue returned ERR_MEM, try tcp_output anyway */
err = tcp_output(conn->pcb.tcp);
#if LWIP_TCPIP_CORE_LOCKING
conn->write_delayed = 1;
#endif
} else {
/* On errors != ERR_MEM, we don't try writing any more but return
the error to the application thread. */
conn->err = err;
write_finished = 1;
}
if (write_finished) {
/* everything was written: set back connection state
and back to application task */
conn->state = NETCONN_NONE;
#if LWIP_TCPIP_CORE_LOCKING
if (conn->write_delayed != 0)
#endif
{
sys_sem_signal(conn->op_completed);
}
}
#if LWIP_TCPIP_CORE_LOCKING
else
return ERR_MEM;
#endif
return ERR_OK;
}
/**
* Receive callback function for RAW netconns.
* Doesn't 'eat' the packet, only references it and sends it to
* conn->recvmbox
*
* @see raw.h (struct raw_pcb.recv) for parameters and return value
*/
static u8_t
recv_raw(void *arg, struct raw_pcb *pcb, struct pbuf *p,
struct ip_addr *addr)
{
struct pbuf *q;
struct netbuf *buf;
struct netconn *conn;
#if LWIP_SO_RCVBUF
int recv_avail;
#endif /* LWIP_SO_RCVBUF */
LWIP_UNUSED_ARG(addr);
conn = arg;
#if LWIP_SO_RCVBUF
SYS_ARCH_GET(conn->recv_avail, recv_avail);
if ((conn != NULL) && (conn->recvmbox != SYS_MBOX_NULL) &&
((recv_avail + (int)(p->tot_len)) <= conn->recv_bufsize)) {
#else /* LWIP_SO_RCVBUF */
if ((conn != NULL) && (conn->recvmbox != SYS_MBOX_NULL)) {
#endif /* LWIP_SO_RCVBUF */
/* copy the whole packet into new pbufs */
q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
if(q != NULL) {
if (pbuf_copy(q, p) != ERR_OK) {
pbuf_free(q);
q = NULL;
}
}
if(q != NULL) {
buf = memp_malloc(MEMP_NETBUF);
if (buf == NULL) {
pbuf_free(q);
return 0;
}
buf->p = q;
buf->ptr = q;
buf->addr = &(((struct ip_hdr*)(q->payload))->src);
buf->port = pcb->protocol;
if (sys_mbox_trypost(conn->recvmbox, buf) != ERR_OK) {
netbuf_delete(buf);
return 0;
} else {
SYS_ARCH_INC(conn->recv_avail, q->tot_len);
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, q->tot_len);
}
}
}
return 0; /* do not eat the packet */
}
#endif /* LWIP_RAW*/
#if LWIP_UDP
/**
* Receive callback function for UDP netconns.
* Posts the packet to conn->recvmbox or deletes it on memory error.
*
* @see udp.h (struct udp_pcb.recv) for parameters
*/
static void
recv_udp(void *arg, struct udp_pcb *pcb, struct pbuf *p,
struct ip_addr *addr, u16_t port)
{
struct netbuf *buf;
struct netconn *conn;
#if LWIP_SO_RCVBUF
int recv_avail;
#endif /* LWIP_SO_RCVBUF */
LWIP_UNUSED_ARG(pcb); /* only used for asserts... */
LWIP_ASSERT("recv_udp must have a pcb argument", pcb != NULL);
LWIP_ASSERT("recv_udp must have an argument", arg != NULL);
conn = arg;
LWIP_ASSERT("recv_udp: recv for wrong pcb!", conn->pcb.udp == pcb);
#if LWIP_SO_RCVBUF
SYS_ARCH_GET(conn->recv_avail, recv_avail);
if ((conn == NULL) || (conn->recvmbox == SYS_MBOX_NULL) ||
((recv_avail + (int)(p->tot_len)) > conn->recv_bufsize)) {
#else /* LWIP_SO_RCVBUF */
if ((conn == NULL) || (conn->recvmbox == SYS_MBOX_NULL)) {
#endif /* LWIP_SO_RCVBUF */
pbuf_free(p);
return;
}
buf = memp_malloc(MEMP_NETBUF);
if (buf == NULL) {
pbuf_free(p);
return;
} else {
buf->p = p;
buf->ptr = p;
buf->addr = addr;
buf->port = port;
#if LWIP_NETBUF_RECVINFO
{
const struct ip_hdr* iphdr = ip_current_header();
/* get the UDP header - always in the first pbuf, ensured by udp_input */
const struct udp_hdr* udphdr = (void*)(((char*)iphdr) + IPH_LEN(iphdr));
buf->toaddr = (struct ip_addr*)&iphdr->dest;
buf->toport = udphdr->dest;
}
#endif /* LWIP_NETBUF_RECVINFO */
}
if (sys_mbox_trypost(conn->recvmbox, buf) != ERR_OK) {
netbuf_delete(buf);
return;
} else {
SYS_ARCH_INC(conn->recv_avail, p->tot_len);
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, p->tot_len);
}
}
#endif /* LWIP_UDP */
#if LWIP_TCP
/**
* Receive callback function for TCP netconns.
* Posts the packet to conn->recvmbox, but doesn't delete it on errors.
*
* @see tcp.h (struct tcp_pcb.recv) for parameters and return value
*/
static err_t
recv_tcp(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
{
struct netconn *conn;
u16_t len;
LWIP_UNUSED_ARG(pcb);
LWIP_ASSERT("recv_tcp must have a pcb argument", pcb != NULL);
LWIP_ASSERT("recv_tcp must have an argument", arg != NULL);
conn = arg;
LWIP_ASSERT("recv_tcp: recv for wrong pcb!", conn->pcb.tcp == pcb);
if ((conn == NULL) || (conn->recvmbox == SYS_MBOX_NULL)) {
return ERR_VAL;
}
conn->err = err;
if (p != NULL) {
len = p->tot_len;
SYS_ARCH_INC(conn->recv_avail, len);
} else {
len = 0;
}
if (sys_mbox_trypost(conn->recvmbox, p) != ERR_OK) {
return ERR_MEM;
} else {
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, len);
}
return ERR_OK;
}
/**
* Poll callback function for TCP netconns.
* Wakes up an application thread that waits for a connection to close
* or data to be sent. The application thread then takes the
* appropriate action to go on.
*
* Signals the conn->sem.
* netconn_close waits for conn->sem if closing failed.
*
* @see tcp.h (struct tcp_pcb.poll) for parameters and return value
*/
static err_t
poll_tcp(void *arg, struct tcp_pcb *pcb)
{
struct netconn *conn = arg;
LWIP_UNUSED_ARG(pcb);
LWIP_ASSERT("conn != NULL", (conn != NULL));
if (conn->state == NETCONN_WRITE) {
do_writemore(conn);
} else if (conn->state == NETCONN_CLOSE) {
do_close_internal(conn);
}
return ERR_OK;
}
/**
* Sent callback function for TCP netconns.
* Signals the conn->sem and calls API_EVENT.
* netconn_write waits for conn->sem if send buffer is low.
*
* @see tcp.h (struct tcp_pcb.sent) for parameters and return value
*/
static err_t
sent_tcp(void *arg, struct tcp_pcb *pcb, u16_t len)
{
struct netconn *conn = arg;
LWIP_UNUSED_ARG(pcb);
LWIP_ASSERT("conn != NULL", (conn != NULL));
if (conn->state == NETCONN_WRITE) {
LWIP_ASSERT("conn->pcb.tcp != NULL", conn->pcb.tcp != NULL);
do_writemore(conn);
} else if (conn->state == NETCONN_CLOSE) {
do_close_internal(conn);
}
if (conn) {
if ((conn->pcb.tcp != NULL) && (tcp_sndbuf(conn->pcb.tcp) > TCP_SNDLOWAT)) {
API_EVENT(conn, NETCONN_EVT_SENDPLUS, len);
}
}
return ERR_OK;
}
/**
* Error callback function for TCP netconns.
* Signals conn->sem, posts to all conn mboxes and calls API_EVENT.
* The application thread has then to decide what to do.
*
* @see tcp.h (struct tcp_pcb.err) for parameters
*/
static void
err_tcp(void *arg, err_t err)
{
struct netconn *conn;
conn = arg;
LWIP_ASSERT("conn != NULL", (conn != NULL));
conn->pcb.tcp = NULL;
conn->err = err;
if (conn->recvmbox != SYS_MBOX_NULL) {
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
sys_mbox_post(conn->recvmbox, NULL);
}
if (conn->op_completed != SYS_SEM_NULL && conn->state == NETCONN_CONNECT) {
conn->state = NETCONN_NONE;
sys_sem_signal(conn->op_completed);
}
if (conn->acceptmbox != SYS_MBOX_NULL) {
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
sys_mbox_post(conn->acceptmbox, NULL);
}
if ((conn->state == NETCONN_WRITE) || (conn->state == NETCONN_CLOSE)) {
/* calling do_writemore/do_close_internal is not necessary
since the pcb has already been deleted! */
conn->state = NETCONN_NONE;
/* wake up the waiting task */
sys_sem_signal(conn->op_completed);
}
}
/**
* Setup a tcp_pcb with the correct callback function pointers
* and their arguments.
*
* @param conn the TCP netconn to setup
*/
static void
setup_tcp(struct netconn *conn)
{
struct tcp_pcb *pcb;
pcb = conn->pcb.tcp;
tcp_arg(pcb, conn);
tcp_recv(pcb, recv_tcp);
tcp_sent(pcb, sent_tcp);
tcp_poll(pcb, poll_tcp, 4);
tcp_err(pcb, err_tcp);
}
/**
* Accept callback function for TCP netconns.
* Allocates a new netconn and posts that to conn->acceptmbox.
*
* @see tcp.h (struct tcp_pcb_listen.accept) for parameters and return value
*/
static err_t
accept_function(void *arg, struct tcp_pcb *newpcb, err_t err)
{
struct netconn *newconn;
struct netconn *conn;
#if API_MSG_DEBUG
#if TCP_DEBUG
tcp_debug_print_state(newpcb->state);
#endif /* TCP_DEBUG */
#endif /* API_MSG_DEBUG */
conn = (struct netconn *)arg;
LWIP_ERROR("accept_function: invalid conn->acceptmbox",
conn->acceptmbox != SYS_MBOX_NULL, return ERR_VAL;);
/* We have to set the callback here even though
* the new socket is unknown. conn->socket is marked as -1. */
newconn = netconn_alloc(conn->type, conn->callback);
if (newconn == NULL) {
return ERR_MEM;
}
newconn->pcb.tcp = newpcb;
setup_tcp(newconn);
newconn->err = err;
if (sys_mbox_trypost(conn->acceptmbox, newconn) != ERR_OK) {
/* When returning != ERR_OK, the connection is aborted in tcp_process(),
so do nothing here! */
newconn->pcb.tcp = NULL;
netconn_free(newconn);
return ERR_MEM;
} else {
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
}
return ERR_OK;
}
#endif /* LWIP_TCP */
/**
* Create a new pcb of a specific type.
* Called from do_newconn().
*
* @param msg the api_msg_msg describing the connection type
* @return msg->conn->err, but the return value is currently ignored
*/
static err_t
pcb_new(struct api_msg_msg *msg)
{
msg->conn->err = ERR_OK;
LWIP_ASSERT("pcb_new: pcb already allocated", msg->conn->pcb.tcp == NULL);
/* Allocate a PCB for this connection */
switch(NETCONNTYPE_GROUP(msg->conn->type)) {
#if LWIP_RAW
case NETCONN_RAW:
msg->conn->pcb.raw = raw_new(msg->msg.n.proto);
if(msg->conn->pcb.raw == NULL) {
msg->conn->err = ERR_MEM;
break;
}
raw_recv(msg->conn->pcb.raw, recv_raw, msg->conn);
break;
#endif /* LWIP_RAW */
#if LWIP_UDP
case NETCONN_UDP:
msg->conn->pcb.udp = udp_new();
if(msg->conn->pcb.udp == NULL) {
msg->conn->err = ERR_MEM;
break;
}
#if LWIP_UDPLITE
if (msg->conn->type==NETCONN_UDPLITE) {
udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_UDPLITE);
}
#endif /* LWIP_UDPLITE */
if (msg->conn->type==NETCONN_UDPNOCHKSUM) {
udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_NOCHKSUM);
}
udp_recv(msg->conn->pcb.udp, recv_udp, msg->conn);
break;
#endif /* LWIP_UDP */
#if LWIP_TCP
case NETCONN_TCP:
msg->conn->pcb.tcp = tcp_new();
if(msg->conn->pcb.tcp == NULL) {
msg->conn->err = ERR_MEM;
break;
}
setup_tcp(msg->conn);
break;
#endif /* LWIP_TCP */
default:
/* Unsupported netconn type, e.g. protocol disabled */
msg->conn->err = ERR_VAL;
break;
}
return msg->conn->err;
}
/**
* Internal helper function to close a TCP netconn: since this sometimes
* doesn't work at the first attempt, this function is called from multiple
* places.
*
* @param conn the TCP netconn to close
*/
static void
do_close_internal(struct netconn *conn)
{
LWIP_DEBUGF(ALII_4573_CLOSE_DEBUG, ("Begin do_close_internal conn=%08x conn->pcb.tcp=%08x localport=%d remoteip=%08x remoteport=%d\n", conn, conn->pcb.tcp, conn->pcb.tcp->local_port, conn->pcb.tcp->remote_ip, conn->pcb.tcp->remote_port));
err_t err;
u8_t shut, shut_rx, shut_tx, close;
LWIP_ASSERT("invalid conn", (conn != NULL));
LWIP_ASSERT("this is for tcp netconns only", (conn->type == NETCONN_TCP));
LWIP_ASSERT("conn must be in state NETCONN_CLOSE", (conn->state == NETCONN_CLOSE));
LWIP_ASSERT("pcb already closed", (conn->pcb.tcp != NULL));
LWIP_ASSERT("conn->current_msg != NULL", conn->current_msg != NULL);
shut = conn->current_msg->msg.sd.shut;
shut_rx = shut & NETCONN_SHUT_RD;
shut_tx = shut & NETCONN_SHUT_WR;
/* shutting down both ends is the same as closing */
close = shut == NETCONN_SHUT_RDWR;
/* Set back some callback pointers */
if (close) {
tcp_arg(conn->pcb.tcp, NULL);
}
if (conn->pcb.tcp->state == LISTEN) {
tcp_accept(conn->pcb.tcp, NULL);
} else {
/* some callbacks have to be reset if tcp_close is not successful */
if (shut_rx) {
tcp_recv(conn->pcb.tcp, NULL);
tcp_accept(conn->pcb.tcp, NULL);
}
if (shut_tx) {
tcp_sent(conn->pcb.tcp, NULL);
}
if (close) {
tcp_poll(conn->pcb.tcp, NULL, 4);
tcp_err(conn->pcb.tcp, NULL);
}
}
/* Try to close the connection */
if (close) {
LWIP_DEBUGF(ALII_4573_CLOSE_DEBUG, ("close:calling tcp_close conn=%08x conn->pcb.tcp=%08x\n", conn, conn->pcb.tcp));
err = tcp_close(conn->pcb.tcp);
} else {
LWIP_DEBUGF(ALII_4573_CLOSE_DEBUG, ("close:shutdown:calling tcp_shutdown conn=%08x conn->pcb.tcp=%08x\n", conn, conn->pcb.tcp));
err = tcp_shutdown(conn->pcb.tcp, shut_rx, shut_tx);
}
int close_always_returns = 0;
#if defined ALII_4573_CLOSE_ALWAYS_RETURNS && ALII_4573_CLOSE_ALWAYS_RETURNS
close_always_returns = 1;
#endif
if ((close_always_returns)||(err == ERR_OK)) {
LWIP_DEBUGF(ALII_4573_CLOSE_DEBUG, ("Closing succeeded conn=%08x conn->pcb.tcp=%08x err=%d\n", conn, conn->pcb.tcp, err));
/* Closing succeeded */
conn->current_msg->err = err;
conn->current_msg = NULL;
conn->state = NETCONN_NONE;
if (close) {
/* Set back some callback pointers as conn is going away */
conn->pcb.tcp = NULL;
/* Trigger select() in socket layer. Make sure everybody notices activity
on the connection, error first! */
API_EVENT(conn, NETCONN_EVT_ERROR, 0);
}
if (shut_rx) {
API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
}
if (shut_tx) {
API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
}
/* wake up the application task */
LWIP_DEBUGF(ALII_4573_CLOSE_DEBUG, ("wake up the application task conn=%08x conn->pcb.tcp=%08x NETCONN_EVT_SENDPLUS\n", conn, conn->pcb.tcp));
conn_op_completed(conn);
} else {
/* Closing failed, restore some of the callbacks */
/* Closing of listen pcb will never fail! */
LWIP_DEBUGF(ALII_4573_CLOSE_DEBUG, ("close failed conn=%08x conn->pcb.tcp=%08x\n", conn, conn->pcb.tcp));
LWIP_ASSERT("Closing a listen pcb may not fail!", (conn->pcb.tcp->state != LISTEN));
tcp_sent(conn->pcb.tcp, sent_tcp);
tcp_poll(conn->pcb.tcp, poll_tcp, 4);
tcp_err(conn->pcb.tcp, err_tcp);
tcp_arg(conn->pcb.tcp, conn);
/* don't restore recv callback: we don't want to receive any more data */
}
/* If closing didn't succeed, we get called again either
from poll_tcp or from sent_tcp */
LWIP_DEBUGF(ALII_4573_CLOSE_DEBUG, ("End do_close_internal conn=%08x conn->pcb.tcp=%08x\n", conn, conn->pcb.tcp));
}
