task #7865 (implement non-blocking send operation)

This commit is contained in:
goldsimon 2010-02-13 17:08:40 +00:00
parent 49c6ce3703
commit 0792effc2a
5 changed files with 92 additions and 40 deletions

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@ -19,6 +19,10 @@ HISTORY
++ New features:
2010-02-13: Simon Goldschmidt
* api.h, api_lib.c, api_msg.c, sockets.c: task #7865 (implement non-
blocking send operation)
2010-02-12: Simon Goldschmidt
* sockets.c/.h: Added a minimal version of posix fctl() to have a
standardised way to set O_NONBLOCK for nonblocking sockets.

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@ -527,6 +527,8 @@ netconn_write(struct netconn *conn, const void *dataptr, size_t size, u8_t apifl
return ERR_OK;
}
/* @todo: for non-blocking write, check if 'size' would ever fit into
snd_queue or snd_buf */
msg.function = do_write;
msg.msg.conn = conn;
msg.msg.msg.w.dataptr = dataptr;

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@ -279,6 +279,17 @@ poll_tcp(void *arg, struct tcp_pcb *pcb)
}
/* @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;
}
@ -308,6 +319,7 @@ sent_tcp(void *arg, struct tcp_pcb *pcb, u16_t len)
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);
}
}
@ -1128,11 +1140,13 @@ do_recv(struct api_msg_msg *msg)
static err_t
do_writemore(struct netconn *conn)
{
err_t err;
err_t err = ERR_OK;
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);
LWIP_ASSERT("conn != NULL", conn != NULL);
LWIP_ASSERT("conn->state == NETCONN_WRITE", (conn->state == NETCONN_WRITE));
@ -1159,41 +1173,57 @@ do_writemore(struct netconn *conn)
conn->flags |= NETCONN_FLAG_WRITE_DELAYED;
#endif
}
err = tcp_write(conn->pcb.tcp, dataptr, len, conn->current_msg->msg.w.apiflags);
LWIP_ASSERT("do_writemore: invalid length!", ((conn->write_offset + len) <= conn->current_msg->msg.w.len));
/* if OK or memory error, check available space */
if (((err == ERR_OK) || (err == ERR_MEM)) &&
((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 (dontblock && (len < conn->current_msg->msg.w.len)) {
/* failed to send all data at once -> nonblocking write not possible */
err = ERR_MEM;
}
if (err == ERR_OK) {
conn->write_offset += len;
if (conn->write_offset == conn->current_msg->msg.w.len) {
/* everything was written */
write_finished = 1;
conn->write_offset = 0;
}
tcp_output_nagle(conn->pcb.tcp);
} 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 */
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. */
LWIP_ASSERT("do_writemore: invalid length!", ((conn->write_offset + len) <= conn->current_msg->msg.w.len));
err = tcp_write(conn->pcb.tcp, dataptr, len, conn->current_msg->msg.w.apiflags);
}
if (dontblock && (err == ERR_MEM)) {
/* nonblocking write failed */
write_finished = 1;
err = ERR_WOULBLOCK;
/* let poll_tcp check writable space to mark the pcb
writable again */
conn->flags |= NETCONN_FLAG_CHECK_WRITESPACE;
/* let select mark this pcb as non-writable. */
API_EVENT(conn, NETCONN_EVT_SENDMINUS, len);
} else {
/* if OK or memory error, check available space */
if (((err == ERR_OK) || (err == ERR_MEM)) &&
((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) {
/* everything was written */
write_finished = 1;
conn->write_offset = 0;
}
tcp_output_nagle(conn->pcb.tcp);
} 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 */
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;
}
}
if (write_finished) {
@ -1232,6 +1262,7 @@ do_write(struct api_msg_msg *msg)
if (msg->conn->type == NETCONN_TCP) {
#if LWIP_TCP
if (msg->conn->state != NETCONN_NONE) {
/* netconn is connecting, closing or in blocking write */
msg->err = ERR_INPROGRESS;
} else if (msg->conn->pcb.tcp != NULL) {
msg->conn->state = NETCONN_WRITE;

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@ -683,6 +683,7 @@ lwip_send(int s, const void *data, size_t size, int flags)
{
struct lwip_socket *sock;
err_t err;
u8_t write_flags;
LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d, data=%p, size=%"SZT_F", flags=0x%x)\n",
s, data, size, flags));
@ -700,7 +701,18 @@ lwip_send(int s, const void *data, size_t size, int flags)
#endif /* (LWIP_UDP || LWIP_RAW) */
}
err = netconn_write(sock->conn, data, size, NETCONN_COPY | ((flags & MSG_MORE)?NETCONN_MORE:0));
if ((flags & MSG_DONTWAIT) || netconn_is_nonblocking(sock->conn)) {
if ((size > TCP_SND_BUF) || ((size / TCP_MSS) > TCP_SND_QUEUELEN)) {
/* too much data to ever send nonblocking! */
sock_set_errno(sock, EMSGSIZE);
return -1;
}
}
write_flags = NETCONN_COPY |
((flags & MSG_MORE) ? NETCONN_MORE : 0) |
((flags & MSG_DONTWAIT) ? NETCONN_DONTBLOCK : 0);
err = netconn_write(sock->conn, data, size, write_flags);
LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) err=%d size=%"SZT_F"\n", s, err, size));
sock_set_errno(sock, err_to_errno(err));

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@ -51,14 +51,14 @@ extern "C" {
* the same byte order as in the corresponding pcb.
*/
/* Flags for netconn_write */
#define NETCONN_NOFLAG 0x00
#define NETCONN_NOCOPY 0x00 /* Only for source code compatibility */
#define NETCONN_COPY 0x01
#define NETCONN_MORE 0x02
/* Flags for netconn_write (u8_t) */
#define NETCONN_NOFLAG 0x00
#define NETCONN_NOCOPY 0x00 /* Only for source code compatibility */
#define NETCONN_COPY 0x01
#define NETCONN_MORE 0x02
#define NETCONN_DONTBLOCK 0x04
/* Flags for struct netconn.flags (u8_t) */
/** TCP: when data passed to netconn_write doesn't fit into the send buffer,
this temporarily stores whether to wake up the original application task
if data couldn't be sent in the first try. */
@ -70,6 +70,9 @@ extern "C" {
/** If this is set, a TCP netconn must call netconn_recved() to update
the TCP receive window (done automatically if not set). */
#define NETCONN_FLAG_NO_AUTO_RECVED 0x08
/** If a nonblocking write has been rejected before, poll_tcp needs to
check if the netconn is writable again */
#define NETCONN_FLAG_CHECK_WRITESPACE 0x10
/* Helpers to process several netconn_types by the same code */