minix/lib/liblwip/api/api_lib.c

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/**
* @file
* Sequential API External module
*
*/
/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
/* This is the part of the API that is linked with
the application */
#include "lwip/opt.h"
#if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
#include "lwip/api.h"
#include "lwip/tcpip.h"
#include "lwip/memp.h"
#include "lwip/ip.h"
#include "lwip/raw.h"
#include "lwip/udp.h"
#include "lwip/tcp.h"
#include <string.h>
/**
* Create a new netconn (of a specific type) that has a callback function.
* The corresponding pcb is also created.
*
* @param t the type of 'connection' to create (@see enum netconn_type)
* @param proto the IP protocol for RAW IP pcbs
* @param callback a function to call on status changes (RX available, TX'ed)
* @return a newly allocated struct netconn or
* NULL on memory error
*/
struct netconn*
netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto, netconn_callback callback)
{
struct netconn *conn;
struct api_msg msg;
conn = netconn_alloc(t, callback);
if (conn != NULL) {
msg.function = do_newconn;
msg.msg.msg.n.proto = proto;
msg.msg.conn = conn;
if (TCPIP_APIMSG(&msg) != ERR_OK) {
LWIP_ASSERT("freeing conn without freeing pcb", conn->pcb.tcp == NULL);
LWIP_ASSERT("conn has no op_completed", sys_sem_valid(&conn->op_completed));
LWIP_ASSERT("conn has no recvmbox", sys_mbox_valid(&conn->recvmbox));
#if LWIP_TCP
LWIP_ASSERT("conn->acceptmbox shouldn't exist", !sys_mbox_valid(&conn->acceptmbox));
#endif /* LWIP_TCP */
sys_sem_free(&conn->op_completed);
sys_mbox_free(&conn->recvmbox);
memp_free(MEMP_NETCONN, conn);
return NULL;
}
}
return conn;
}
/**
* Close a netconn 'connection' and free its resources.
* UDP and RAW connection are completely closed, TCP pcbs might still be in a waitstate
* after this returns.
*
* @param conn the netconn to delete
* @return ERR_OK if the connection was deleted
*/
err_t
netconn_delete(struct netconn *conn)
{
struct api_msg msg;
/* No ASSERT here because possible to get a (conn == NULL) if we got an accept error */
if (conn == NULL) {
return ERR_OK;
}
msg.function = do_delconn;
msg.msg.conn = conn;
tcpip_apimsg(&msg);
netconn_free(conn);
/* don't care for return value of do_delconn since it only calls void functions */
return ERR_OK;
}
/**
* Get the local or remote IP address and port of a netconn.
* For RAW netconns, this returns the protocol instead of a port!
*
* @param conn the netconn to query
* @param addr a pointer to which to save the IP address
* @param port a pointer to which to save the port (or protocol for RAW)
* @param local 1 to get the local IP address, 0 to get the remote one
* @return ERR_CONN for invalid connections
* ERR_OK if the information was retrieved
*/
err_t
netconn_getaddr(struct netconn *conn, ip_addr_t *addr, u16_t *port, u8_t local)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_getaddr: invalid conn", (conn != NULL), return ERR_ARG;);
LWIP_ERROR("netconn_getaddr: invalid addr", (addr != NULL), return ERR_ARG;);
LWIP_ERROR("netconn_getaddr: invalid port", (port != NULL), return ERR_ARG;);
msg.function = do_getaddr;
msg.msg.conn = conn;
msg.msg.msg.ad.ipaddr = addr;
msg.msg.msg.ad.port = port;
msg.msg.msg.ad.local = local;
err = TCPIP_APIMSG(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Bind a netconn to a specific local IP address and port.
* Binding one netconn twice might not always be checked correctly!
*
* @param conn the netconn to bind
* @param addr the local IP address to bind the netconn to (use IP_ADDR_ANY
* to bind to all addresses)
* @param port the local port to bind the netconn to (not used for RAW)
* @return ERR_OK if bound, any other err_t on failure
*/
err_t
netconn_bind(struct netconn *conn, ip_addr_t *addr, u16_t port)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_bind: invalid conn", (conn != NULL), return ERR_ARG;);
msg.function = do_bind;
msg.msg.conn = conn;
msg.msg.msg.bc.ipaddr = addr;
msg.msg.msg.bc.port = port;
err = TCPIP_APIMSG(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Connect a netconn to a specific remote IP address and port.
*
* @param conn the netconn to connect
* @param addr the remote IP address to connect to
* @param port the remote port to connect to (no used for RAW)
* @return ERR_OK if connected, return value of tcp_/udp_/raw_connect otherwise
*/
err_t
netconn_connect(struct netconn *conn, ip_addr_t *addr, u16_t port)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_connect: invalid conn", (conn != NULL), return ERR_ARG;);
msg.function = do_connect;
msg.msg.conn = conn;
msg.msg.msg.bc.ipaddr = addr;
msg.msg.msg.bc.port = port;
/* This is the only function which need to not block tcpip_thread */
err = tcpip_apimsg(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Disconnect a netconn from its current peer (only valid for UDP netconns).
*
* @param conn the netconn to disconnect
* @return TODO: return value is not set here...
*/
err_t
netconn_disconnect(struct netconn *conn)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_disconnect: invalid conn", (conn != NULL), return ERR_ARG;);
msg.function = do_disconnect;
msg.msg.conn = conn;
err = TCPIP_APIMSG(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Set a TCP netconn into listen mode
*
* @param conn the tcp netconn to set to listen mode
* @param backlog the listen backlog, only used if TCP_LISTEN_BACKLOG==1
* @return ERR_OK if the netconn was set to listen (UDP and RAW netconns
* don't return any error (yet?))
*/
err_t
netconn_listen_with_backlog(struct netconn *conn, u8_t backlog)
{
struct api_msg msg;
err_t err;
/* This does no harm. If TCP_LISTEN_BACKLOG is off, backlog is unused. */
LWIP_UNUSED_ARG(backlog);
LWIP_ERROR("netconn_listen: invalid conn", (conn != NULL), return ERR_ARG;);
msg.function = do_listen;
msg.msg.conn = conn;
#if TCP_LISTEN_BACKLOG
msg.msg.msg.lb.backlog = backlog;
#endif /* TCP_LISTEN_BACKLOG */
err = TCPIP_APIMSG(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Accept a new connection on a TCP listening netconn.
*
* @param conn the TCP listen netconn
* @param new_conn pointer where the new connection is stored
* @return ERR_OK if a new connection has been received or an error
* code otherwise
*/
err_t
netconn_accept(struct netconn *conn, struct netconn **new_conn)
{
#if LWIP_TCP
struct netconn *newconn;
err_t err;
#if TCP_LISTEN_BACKLOG
struct api_msg msg;
#endif /* TCP_LISTEN_BACKLOG */
LWIP_ERROR("netconn_accept: invalid pointer", (new_conn != NULL), return ERR_ARG;);
*new_conn = NULL;
LWIP_ERROR("netconn_accept: invalid conn", (conn != NULL), return ERR_ARG;);
LWIP_ERROR("netconn_accept: invalid acceptmbox", sys_mbox_valid(&conn->acceptmbox), return ERR_ARG;);
err = conn->last_err;
if (ERR_IS_FATAL(err)) {
/* don't recv on fatal errors: this might block the application task
waiting on acceptmbox forever! */
return err;
}
#if LWIP_SO_RCVTIMEO
if (sys_arch_mbox_fetch(&conn->acceptmbox, (void **)&newconn, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
NETCONN_SET_SAFE_ERR(conn, ERR_TIMEOUT);
return ERR_TIMEOUT;
}
#else
sys_arch_mbox_fetch(&conn->acceptmbox, (void **)&newconn, 0);
#endif /* LWIP_SO_RCVTIMEO*/
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
if (newconn == NULL) {
/* connection has been closed */
NETCONN_SET_SAFE_ERR(conn, ERR_CLSD);
return ERR_CLSD;
}
#if TCP_LISTEN_BACKLOG
/* Let the stack know that we have accepted the connection. */
msg.function = do_recv;
msg.msg.conn = conn;
/* don't care for the return value of do_recv */
TCPIP_APIMSG(&msg);
#endif /* TCP_LISTEN_BACKLOG */
*new_conn = newconn;
/* don't set conn->last_err: it's only ERR_OK, anyway */
return ERR_OK;
#else /* LWIP_TCP */
LWIP_UNUSED_ARG(conn);
LWIP_UNUSED_ARG(new_conn);
return ERR_ARG;
#endif /* LWIP_TCP */
}
/**
* Receive data: actual implementation that doesn't care whether pbuf or netbuf
* is received
*
* @param conn the netconn from which to receive data
* @param new_buf pointer where a new pbuf/netbuf is stored when received data
* @return ERR_OK if data has been received, an error code otherwise (timeout,
* memory error or another error)
*/
static err_t
netconn_recv_data(struct netconn *conn, void **new_buf)
{
void *buf = NULL;
u16_t len;
err_t err;
#if LWIP_TCP
struct api_msg msg;
#endif /* LWIP_TCP */
LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
*new_buf = NULL;
LWIP_ERROR("netconn_recv: invalid conn", (conn != NULL), return ERR_ARG;);
LWIP_ERROR("netconn_accept: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);
err = conn->last_err;
if (ERR_IS_FATAL(err)) {
/* don't recv on fatal errors: this might block the application task
waiting on recvmbox forever! */
/* @todo: this does not allow us to fetch data that has been put into recvmbox
before the fatal error occurred - is that a problem? */
return err;
}
#if LWIP_SO_RCVTIMEO
if (sys_arch_mbox_fetch(&conn->recvmbox, &buf, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
NETCONN_SET_SAFE_ERR(conn, ERR_TIMEOUT);
return ERR_TIMEOUT;
}
#else
sys_arch_mbox_fetch(&conn->recvmbox, &buf, 0);
#endif /* LWIP_SO_RCVTIMEO*/
#if LWIP_TCP
if (conn->type == NETCONN_TCP) {
if (!netconn_get_noautorecved(conn) || (buf == NULL)) {
/* Let the stack know that we have taken the data. */
/* TODO: Speedup: Don't block and wait for the answer here
(to prevent multiple thread-switches). */
msg.function = do_recv;
msg.msg.conn = conn;
if (buf != NULL) {
msg.msg.msg.r.len = ((struct pbuf *)buf)->tot_len;
} else {
msg.msg.msg.r.len = 1;
}
/* don't care for the return value of do_recv */
TCPIP_APIMSG(&msg);
}
/* If we are closed, we indicate that we no longer wish to use the socket */
if (buf == NULL) {
API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
/* Avoid to lose any previous error code */
NETCONN_SET_SAFE_ERR(conn, ERR_CLSD);
return ERR_CLSD;
}
len = ((struct pbuf *)buf)->tot_len;
}
#endif /* LWIP_TCP */
#if LWIP_TCP && (LWIP_UDP || LWIP_RAW)
else
#endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
#if (LWIP_UDP || LWIP_RAW)
{
LWIP_ASSERT("buf != NULL", buf != NULL);
len = netbuf_len((struct netbuf *)buf);
}
#endif /* (LWIP_UDP || LWIP_RAW) */
SYS_ARCH_DEC(conn->recv_avail, len);
/* Register event with callback */
API_EVENT(conn, NETCONN_EVT_RCVMINUS, len);
LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_recv_data: received %p, len=%"U16_F"\n", buf, len));
*new_buf = buf;
/* don't set conn->last_err: it's only ERR_OK, anyway */
return ERR_OK;
}
/**
* Receive data (in form of a pbuf) from a TCP netconn
*
* @param conn the netconn from which to receive data
* @param new_buf pointer where a new pbuf is stored when received data
* @return ERR_OK if data has been received, an error code otherwise (timeout,
* memory error or another error)
* ERR_ARG if conn is not a TCP netconn
*/
err_t
netconn_recv_tcp_pbuf(struct netconn *conn, struct pbuf **new_buf)
{
LWIP_ERROR("netconn_recv: invalid conn", (conn != NULL) &&
netconn_type(conn) == NETCONN_TCP, return ERR_ARG;);
return netconn_recv_data(conn, (void **)new_buf);
}
/**
* Receive data (in form of a netbuf containing a packet buffer) from a netconn
*
* @param conn the netconn from which to receive data
* @param new_buf pointer where a new netbuf is stored when received data
* @return ERR_OK if data has been received, an error code otherwise (timeout,
* memory error or another error)
*/
err_t
netconn_recv(struct netconn *conn, struct netbuf **new_buf)
{
#if LWIP_TCP
struct netbuf *buf = NULL;
err_t err;
#endif /* LWIP_TCP */
LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
*new_buf = NULL;
LWIP_ERROR("netconn_recv: invalid conn", (conn != NULL), return ERR_ARG;);
LWIP_ERROR("netconn_accept: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);
#if LWIP_TCP
if (conn->type == NETCONN_TCP) {
struct pbuf *p = NULL;
/* This is not a listening netconn, since recvmbox is set */
buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
if (buf == NULL) {
NETCONN_SET_SAFE_ERR(conn, ERR_MEM);
return ERR_MEM;
}
err = netconn_recv_data(conn, (void **)&p);
if (err != ERR_OK) {
memp_free(MEMP_NETBUF, buf);
return err;
}
LWIP_ASSERT("p != NULL", p != NULL);
buf->p = p;
buf->ptr = p;
buf->port = 0;
ip_addr_set_any(&buf->addr);
*new_buf = buf;
/* don't set conn->last_err: it's only ERR_OK, anyway */
return ERR_OK;
} else
#endif /* LWIP_TCP */
{
#if (LWIP_UDP || LWIP_RAW)
return netconn_recv_data(conn, (void **)new_buf);
#endif /* (LWIP_UDP || LWIP_RAW) */
}
}
/**
* TCP: update the receive window: by calling this, the application
* tells the stack that it has processed data and is able to accept
* new data.
* ATTENTION: use with care, this is mainly used for sockets!
* Can only be used when calling netconn_set_noautorecved(conn, 1) before.
*
* @param conn the netconn for which to update the receive window
* @param length amount of data processed (ATTENTION: this must be accurate!)
*/
void
netconn_recved(struct netconn *conn, u32_t length)
{
if ((conn != NULL) && (conn->type == NETCONN_TCP) &&
(netconn_get_noautorecved(conn))) {
struct api_msg msg;
/* Let the stack know that we have taken the data. */
/* TODO: Speedup: Don't block and wait for the answer here
(to prevent multiple thread-switches). */
msg.function = do_recv;
msg.msg.conn = conn;
msg.msg.msg.r.len = length;
/* don't care for the return value of do_recv */
TCPIP_APIMSG(&msg);
}
}
/**
* Send data (in form of a netbuf) to a specific remote IP address and port.
* Only to be used for UDP and RAW netconns (not TCP).
*
* @param conn the netconn over which to send data
* @param buf a netbuf containing the data to send
* @param addr the remote IP address to which to send the data
* @param port the remote port to which to send the data
* @return ERR_OK if data was sent, any other err_t on error
*/
err_t
netconn_sendto(struct netconn *conn, struct netbuf *buf, ip_addr_t *addr, u16_t port)
{
if (buf != NULL) {
ip_addr_set(&buf->addr, addr);
buf->port = port;
return netconn_send(conn, buf);
}
return ERR_VAL;
}
/**
* Send data over a UDP or RAW netconn (that is already connected).
*
* @param conn the UDP or RAW netconn over which to send data
* @param buf a netbuf containing the data to send
* @return ERR_OK if data was sent, any other err_t on error
*/
err_t
netconn_send(struct netconn *conn, struct netbuf *buf)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_send: invalid conn", (conn != NULL), return ERR_ARG;);
LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_send: sending %"U16_F" bytes\n", buf->p->tot_len));
msg.function = do_send;
msg.msg.conn = conn;
msg.msg.msg.b = buf;
err = TCPIP_APIMSG(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Send data over a TCP netconn.
*
* @param conn the TCP netconn over which to send data
* @param dataptr pointer to the application buffer that contains the data to send
* @param size size of the application data to send
* @param apiflags combination of following flags :
* - NETCONN_COPY: data will be copied into memory belonging to the stack
* - NETCONN_MORE: for TCP connection, PSH flag will be set on last segment sent
* - NETCONN_DONTBLOCK: only write the data if all dat can be written at once
* @return ERR_OK if data was sent, any other err_t on error
*/
err_t
netconn_write(struct netconn *conn, const void *dataptr, size_t size, u8_t apiflags)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_write: invalid conn", (conn != NULL), return ERR_ARG;);
LWIP_ERROR("netconn_write: invalid conn->type", (conn->type == NETCONN_TCP), return ERR_VAL;);
if (size == 0) {
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;
msg.msg.msg.w.apiflags = apiflags;
msg.msg.msg.w.len = size;
/* For locking the core: this _can_ be delayed on low memory/low send buffer,
but if it is, this is done inside api_msg.c:do_write(), so we can use the
non-blocking version here. */
err = TCPIP_APIMSG(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Close ot shutdown a TCP netconn (doesn't delete it).
*
* @param conn the TCP netconn to close or shutdown
* @param how fully close or only shutdown one side?
* @return ERR_OK if the netconn was closed, any other err_t on error
*/
static err_t
netconn_close_shutdown(struct netconn *conn, u8_t how)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_close: invalid conn", (conn != NULL), return ERR_ARG;);
msg.function = do_close;
msg.msg.conn = conn;
/* shutting down both ends is the same as closing */
msg.msg.msg.sd.shut = how;
/* because of the LWIP_TCPIP_CORE_LOCKING implementation of do_close,
don't use TCPIP_APIMSG here */
err = tcpip_apimsg(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
/**
* Close a TCP netconn (doesn't delete it).
*
* @param conn the TCP netconn to close
* @return ERR_OK if the netconn was closed, any other err_t on error
*/
err_t
netconn_close(struct netconn *conn)
{
/* shutting down both ends is the same as closing */
return netconn_close_shutdown(conn, NETCONN_SHUT_RDWR);
}
/**
* Shut down one or both sides of a TCP netconn (doesn't delete it).
*
* @param conn the TCP netconn to shut down
* @return ERR_OK if the netconn was closed, any other err_t on error
*/
err_t
netconn_shutdown(struct netconn *conn, u8_t shut_rx, u8_t shut_tx)
{
return netconn_close_shutdown(conn, (shut_rx ? NETCONN_SHUT_RD : 0) | (shut_tx ? NETCONN_SHUT_WR : 0));
}
#if LWIP_IGMP
/**
* Join multicast groups for UDP netconns.
*
* @param conn the UDP netconn for which to change multicast addresses
* @param multiaddr IP address of the multicast group to join or leave
* @param netif_addr the IP address of the network interface on which to send
* the igmp message
* @param join_or_leave flag whether to send a join- or leave-message
* @return ERR_OK if the action was taken, any err_t on error
*/
err_t
netconn_join_leave_group(struct netconn *conn,
ip_addr_t *multiaddr,
ip_addr_t *netif_addr,
enum netconn_igmp join_or_leave)
{
struct api_msg msg;
err_t err;
LWIP_ERROR("netconn_join_leave_group: invalid conn", (conn != NULL), return ERR_ARG;);
msg.function = do_join_leave_group;
msg.msg.conn = conn;
msg.msg.msg.jl.multiaddr = multiaddr;
msg.msg.msg.jl.netif_addr = netif_addr;
msg.msg.msg.jl.join_or_leave = join_or_leave;
err = TCPIP_APIMSG(&msg);
NETCONN_SET_SAFE_ERR(conn, err);
return err;
}
#endif /* LWIP_IGMP */
#if LWIP_DNS
/**
* Execute a DNS query, only one IP address is returned
*
* @param name a string representation of the DNS host name to query
* @param addr a preallocated ip_addr_t where to store the resolved IP address
* @return ERR_OK: resolving succeeded
* ERR_MEM: memory error, try again later
* ERR_ARG: dns client not initialized or invalid hostname
* ERR_VAL: dns server response was invalid
*/
err_t
netconn_gethostbyname(const char *name, ip_addr_t *addr)
{
struct dns_api_msg msg;
err_t err;
sys_sem_t sem;
LWIP_ERROR("netconn_gethostbyname: invalid name", (name != NULL), return ERR_ARG;);
LWIP_ERROR("netconn_gethostbyname: invalid addr", (addr != NULL), return ERR_ARG;);
err = sys_sem_new(&sem, 0);
if (err != ERR_OK) {
return err;
}
msg.name = name;
msg.addr = addr;
msg.err = &err;
msg.sem = &sem;
tcpip_callback(do_gethostbyname, &msg);
sys_sem_wait(&sem);
sys_sem_free(&sem);
return err;
}
#endif /* LWIP_DNS*/
#endif /* LWIP_NETCONN */