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api_lib.c

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00001 /**
00002  * @file
00003  * Sequential API External module
00004  *
00005  */
00006  
00007 /*
00008  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
00009  * All rights reserved. 
00010  * 
00011  * Redistribution and use in source and binary forms, with or without modification, 
00012  * are permitted provided that the following conditions are met:
00013  *
00014  * 1. Redistributions of source code must retain the above copyright notice,
00015  *    this list of conditions and the following disclaimer.
00016  * 2. Redistributions in binary form must reproduce the above copyright notice,
00017  *    this list of conditions and the following disclaimer in the documentation
00018  *    and/or other materials provided with the distribution.
00019  * 3. The name of the author may not be used to endorse or promote products
00020  *    derived from this software without specific prior written permission. 
00021  *
00022  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
00023  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
00024  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
00025  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
00026  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
00027  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
00028  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
00029  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
00030  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
00031  * OF SUCH DAMAGE.
00032  *
00033  * This file is part of the lwIP TCP/IP stack.
00034  * 
00035  * Author: Adam Dunkels <adam@sics.se>
00036  *
00037  */
00038 
00039 /* This is the part of the API that is linked with
00040    the application */
00041 
00042 #include "lwip/opt.h"
00043 
00044 #if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
00045 
00046 #include "lwip/api.h"
00047 #include "lwip/tcpip.h"
00048 #include "lwip/memp.h"
00049 
00050 #include "lwip/ip.h"
00051 #include "lwip/raw.h"
00052 #include "lwip/udp.h"
00053 #include "lwip/tcp.h"
00054 
00055 #include <string.h>
00056 
00057 /**
00058  * Create a new netconn (of a specific type) that has a callback function.
00059  * The corresponding pcb is also created.
00060  *
00061  * @param t the type of 'connection' to create (@see enum netconn_type)
00062  * @param proto the IP protocol for RAW IP pcbs
00063  * @param callback a function to call on status changes (RX available, TX'ed)
00064  * @return a newly allocated struct netconn or
00065  *         NULL on memory error
00066  */
00067 struct netconn*
00068 netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto, netconn_callback callback)
00069 {
00070   struct netconn *conn;
00071   struct api_msg msg;
00072 
00073   conn = netconn_alloc(t, callback);
00074   if (conn != NULL) {
00075     msg.function = do_newconn;
00076     msg.msg.msg.n.proto = proto;
00077     msg.msg.conn = conn;
00078     if (TCPIP_APIMSG(&msg) != ERR_OK) {
00079       LWIP_ASSERT("freeing conn without freeing pcb", conn->pcb.tcp == NULL);
00080       LWIP_ASSERT("conn has no op_completed", sys_sem_valid(&conn->op_completed));
00081       LWIP_ASSERT("conn has no recvmbox", sys_mbox_valid(&conn->recvmbox));
00082 #if LWIP_TCP
00083       LWIP_ASSERT("conn->acceptmbox shouldn't exist", !sys_mbox_valid(&conn->acceptmbox));
00084 #endif /* LWIP_TCP */
00085       sys_sem_free(&conn->op_completed);
00086       sys_mbox_free(&conn->recvmbox);
00087       memp_free(MEMP_NETCONN, conn);
00088       return NULL;
00089     }
00090   }
00091   return conn;
00092 }
00093 
00094 /**
00095  * Close a netconn 'connection' and free its resources.
00096  * UDP and RAW connection are completely closed, TCP pcbs might still be in a waitstate
00097  * after this returns.
00098  *
00099  * @param conn the netconn to delete
00100  * @return ERR_OK if the connection was deleted
00101  */
00102 err_t
00103 netconn_delete(struct netconn *conn)
00104 {
00105   struct api_msg msg;
00106 
00107   /* No ASSERT here because possible to get a (conn == NULL) if we got an accept error */
00108   if (conn == NULL) {
00109     return ERR_OK;
00110   }
00111 
00112   msg.function = do_delconn;
00113   msg.msg.conn = conn;
00114   tcpip_apimsg(&msg);
00115 
00116   netconn_free(conn);
00117 
00118   /* don't care for return value of do_delconn since it only calls void functions */
00119 
00120   return ERR_OK;
00121 }
00122 
00123 /**
00124  * Get the local or remote IP address and port of a netconn.
00125  * For RAW netconns, this returns the protocol instead of a port!
00126  *
00127  * @param conn the netconn to query
00128  * @param addr a pointer to which to save the IP address
00129  * @param port a pointer to which to save the port (or protocol for RAW)
00130  * @param local 1 to get the local IP address, 0 to get the remote one
00131  * @return ERR_CONN for invalid connections
00132  *         ERR_OK if the information was retrieved
00133  */
00134 err_t
00135 netconn_getaddr(struct netconn *conn, ip_addr_t *addr, u16_t *port, u8_t local)
00136 {
00137   struct api_msg msg;
00138   err_t err;
00139 
00140   LWIP_ERROR("netconn_getaddr: invalid conn", (conn != NULL), return ERR_ARG;);
00141   LWIP_ERROR("netconn_getaddr: invalid addr", (addr != NULL), return ERR_ARG;);
00142   LWIP_ERROR("netconn_getaddr: invalid port", (port != NULL), return ERR_ARG;);
00143 
00144   msg.function = do_getaddr;
00145   msg.msg.conn = conn;
00146   msg.msg.msg.ad.ipaddr = addr;
00147   msg.msg.msg.ad.port = port;
00148   msg.msg.msg.ad.local = local;
00149   err = TCPIP_APIMSG(&msg);
00150 
00151   NETCONN_SET_SAFE_ERR(conn, err);
00152   return err;
00153 }
00154 
00155 /**
00156  * Bind a netconn to a specific local IP address and port.
00157  * Binding one netconn twice might not always be checked correctly!
00158  *
00159  * @param conn the netconn to bind
00160  * @param addr the local IP address to bind the netconn to (use IP_ADDR_ANY
00161  *             to bind to all addresses)
00162  * @param port the local port to bind the netconn to (not used for RAW)
00163  * @return ERR_OK if bound, any other err_t on failure
00164  */
00165 err_t
00166 netconn_bind(struct netconn *conn, ip_addr_t *addr, u16_t port)
00167 {
00168   struct api_msg msg;
00169   err_t err;
00170 
00171   LWIP_ERROR("netconn_bind: invalid conn", (conn != NULL), return ERR_ARG;);
00172 
00173   msg.function = do_bind;
00174   msg.msg.conn = conn;
00175   msg.msg.msg.bc.ipaddr = addr;
00176   msg.msg.msg.bc.port = port;
00177   err = TCPIP_APIMSG(&msg);
00178 
00179   NETCONN_SET_SAFE_ERR(conn, err);
00180   return err;
00181 }
00182 
00183 /**
00184  * Connect a netconn to a specific remote IP address and port.
00185  *
00186  * @param conn the netconn to connect
00187  * @param addr the remote IP address to connect to
00188  * @param port the remote port to connect to (no used for RAW)
00189  * @return ERR_OK if connected, return value of tcp_/udp_/raw_connect otherwise
00190  */
00191 err_t
00192 netconn_connect(struct netconn *conn, ip_addr_t *addr, u16_t port)
00193 {
00194   struct api_msg msg;
00195   err_t err;
00196 
00197   LWIP_ERROR("netconn_connect: invalid conn", (conn != NULL), return ERR_ARG;);
00198 
00199   msg.function = do_connect;
00200   msg.msg.conn = conn;
00201   msg.msg.msg.bc.ipaddr = addr;
00202   msg.msg.msg.bc.port = port;
00203   /* This is the only function which need to not block tcpip_thread */
00204   err = tcpip_apimsg(&msg);
00205 
00206   NETCONN_SET_SAFE_ERR(conn, err);
00207   return err;
00208 }
00209 
00210 /**
00211  * Disconnect a netconn from its current peer (only valid for UDP netconns).
00212  *
00213  * @param conn the netconn to disconnect
00214  * @return TODO: return value is not set here...
00215  */
00216 err_t
00217 netconn_disconnect(struct netconn *conn)
00218 {
00219   struct api_msg msg;
00220   err_t err;
00221 
00222   LWIP_ERROR("netconn_disconnect: invalid conn", (conn != NULL), return ERR_ARG;);
00223 
00224   msg.function = do_disconnect;
00225   msg.msg.conn = conn;
00226   err = TCPIP_APIMSG(&msg);
00227 
00228   NETCONN_SET_SAFE_ERR(conn, err);
00229   return err;
00230 }
00231 
00232 /**
00233  * Set a TCP netconn into listen mode
00234  *
00235  * @param conn the tcp netconn to set to listen mode
00236  * @param backlog the listen backlog, only used if TCP_LISTEN_BACKLOG==1
00237  * @return ERR_OK if the netconn was set to listen (UDP and RAW netconns
00238  *         don't return any error (yet?))
00239  */
00240 err_t
00241 netconn_listen_with_backlog(struct netconn *conn, u8_t backlog)
00242 {
00243 #if LWIP_TCP
00244   struct api_msg msg;
00245   err_t err;
00246 
00247   /* This does no harm. If TCP_LISTEN_BACKLOG is off, backlog is unused. */
00248   LWIP_UNUSED_ARG(backlog);
00249 
00250   LWIP_ERROR("netconn_listen: invalid conn", (conn != NULL), return ERR_ARG;);
00251 
00252   msg.function = do_listen;
00253   msg.msg.conn = conn;
00254 #if TCP_LISTEN_BACKLOG
00255   msg.msg.msg.lb.backlog = backlog;
00256 #endif /* TCP_LISTEN_BACKLOG */
00257   err = TCPIP_APIMSG(&msg);
00258 
00259   NETCONN_SET_SAFE_ERR(conn, err);
00260   return err;
00261 #else /* LWIP_TCP */
00262   LWIP_UNUSED_ARG(conn);
00263   LWIP_UNUSED_ARG(backlog);
00264   return ERR_ARG;
00265 #endif /* LWIP_TCP */
00266 }
00267 
00268 /**
00269  * Accept a new connection on a TCP listening netconn.
00270  *
00271  * @param conn the TCP listen netconn
00272  * @param new_conn pointer where the new connection is stored
00273  * @return ERR_OK if a new connection has been received or an error
00274  *                code otherwise
00275  */
00276 err_t
00277 netconn_accept(struct netconn *conn, struct netconn **new_conn)
00278 {
00279 #if LWIP_TCP
00280   struct netconn *newconn;
00281   err_t err;
00282 #if TCP_LISTEN_BACKLOG
00283   struct api_msg msg;
00284 #endif /* TCP_LISTEN_BACKLOG */
00285 
00286   LWIP_ERROR("netconn_accept: invalid pointer",    (new_conn != NULL),                  return ERR_ARG;);
00287   *new_conn = NULL;
00288   LWIP_ERROR("netconn_accept: invalid conn",       (conn != NULL),                      return ERR_ARG;);
00289   LWIP_ERROR("netconn_accept: invalid acceptmbox", sys_mbox_valid(&conn->acceptmbox),   return ERR_ARG;);
00290 
00291   err = conn->last_err;
00292   if (ERR_IS_FATAL(err)) {
00293     /* don't recv on fatal errors: this might block the application task
00294        waiting on acceptmbox forever! */
00295     return err;
00296   }
00297 
00298 #if LWIP_SO_RCVTIMEO
00299   if (sys_arch_mbox_fetch(&conn->acceptmbox, (void **)&newconn, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
00300     NETCONN_SET_SAFE_ERR(conn, ERR_TIMEOUT);
00301     return ERR_TIMEOUT;
00302   }
00303 #else
00304   sys_arch_mbox_fetch(&conn->acceptmbox, (void **)&newconn, 0);
00305 #endif /* LWIP_SO_RCVTIMEO*/
00306   /* Register event with callback */
00307   API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
00308 
00309   if (newconn == NULL) {
00310     /* connection has been aborted */
00311     NETCONN_SET_SAFE_ERR(conn, ERR_ABRT);
00312     return ERR_ABRT;
00313   }
00314 #if TCP_LISTEN_BACKLOG
00315   /* Let the stack know that we have accepted the connection. */
00316   msg.function = do_recv;
00317   msg.msg.conn = conn;
00318   /* don't care for the return value of do_recv */
00319   TCPIP_APIMSG(&msg);
00320 #endif /* TCP_LISTEN_BACKLOG */
00321 
00322   *new_conn = newconn;
00323   /* don't set conn->last_err: it's only ERR_OK, anyway */
00324   return ERR_OK;
00325 #else /* LWIP_TCP */
00326   LWIP_UNUSED_ARG(conn);
00327   LWIP_UNUSED_ARG(new_conn);
00328   return ERR_ARG;
00329 #endif /* LWIP_TCP */
00330 }
00331 
00332 /**
00333  * Receive data: actual implementation that doesn't care whether pbuf or netbuf
00334  * is received
00335  *
00336  * @param conn the netconn from which to receive data
00337  * @param new_buf pointer where a new pbuf/netbuf is stored when received data
00338  * @return ERR_OK if data has been received, an error code otherwise (timeout,
00339  *                memory error or another error)
00340  */
00341 static err_t
00342 netconn_recv_data(struct netconn *conn, void **new_buf)
00343 {
00344   void *buf = NULL;
00345   u16_t len;
00346   err_t err;
00347 #if LWIP_TCP
00348   struct api_msg msg;
00349 #endif /* LWIP_TCP */
00350 
00351   LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
00352   *new_buf = NULL;
00353   LWIP_ERROR("netconn_recv: invalid conn",    (conn != NULL),    return ERR_ARG;);
00354   LWIP_ERROR("netconn_accept: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);
00355 
00356   err = conn->last_err;
00357   if (ERR_IS_FATAL(err)) {
00358     /* don't recv on fatal errors: this might block the application task
00359        waiting on recvmbox forever! */
00360     /* @todo: this does not allow us to fetch data that has been put into recvmbox
00361        before the fatal error occurred - is that a problem? */
00362     return err;
00363   }
00364 
00365 #if LWIP_SO_RCVTIMEO
00366   if (sys_arch_mbox_fetch(&conn->recvmbox, &buf, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
00367     NETCONN_SET_SAFE_ERR(conn, ERR_TIMEOUT);
00368     return ERR_TIMEOUT;
00369   }
00370 #else
00371   sys_arch_mbox_fetch(&conn->recvmbox, &buf, 0);
00372 #endif /* LWIP_SO_RCVTIMEO*/
00373 
00374 #if LWIP_TCP
00375   if (conn->type == NETCONN_TCP) {
00376     if (!netconn_get_noautorecved(conn) || (buf == NULL)) {
00377       /* Let the stack know that we have taken the data. */
00378       /* TODO: Speedup: Don't block and wait for the answer here
00379          (to prevent multiple thread-switches). */
00380       msg.function = do_recv;
00381       msg.msg.conn = conn;
00382       if (buf != NULL) {
00383         msg.msg.msg.r.len = ((struct pbuf *)buf)->tot_len;
00384       } else {
00385         msg.msg.msg.r.len = 1;
00386       }
00387       /* don't care for the return value of do_recv */
00388       TCPIP_APIMSG(&msg);
00389     }
00390 
00391     /* If we are closed, we indicate that we no longer wish to use the socket */
00392     if (buf == NULL) {
00393       API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
00394       /* Avoid to lose any previous error code */
00395       NETCONN_SET_SAFE_ERR(conn, ERR_CLSD);
00396       return ERR_CLSD;
00397     }
00398     len = ((struct pbuf *)buf)->tot_len;
00399   }
00400 #endif /* LWIP_TCP */
00401 #if LWIP_TCP && (LWIP_UDP || LWIP_RAW)
00402   else
00403 #endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
00404 #if (LWIP_UDP || LWIP_RAW)
00405   {
00406     LWIP_ASSERT("buf != NULL", buf != NULL);
00407     len = netbuf_len((struct netbuf *)buf);
00408   }
00409 #endif /* (LWIP_UDP || LWIP_RAW) */
00410 
00411 #if LWIP_SO_RCVBUF
00412   SYS_ARCH_DEC(conn->recv_avail, len);
00413 #endif /* LWIP_SO_RCVBUF */
00414   /* Register event with callback */
00415   API_EVENT(conn, NETCONN_EVT_RCVMINUS, len);
00416 
00417   LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_recv_data: received %p, len=%"U16_F"\n", buf, len));
00418 
00419   *new_buf = buf;
00420   /* don't set conn->last_err: it's only ERR_OK, anyway */
00421   return ERR_OK;
00422 }
00423 
00424 /**
00425  * Receive data (in form of a pbuf) from a TCP netconn
00426  *
00427  * @param conn the netconn from which to receive data
00428  * @param new_buf pointer where a new pbuf is stored when received data
00429  * @return ERR_OK if data has been received, an error code otherwise (timeout,
00430  *                memory error or another error)
00431  *         ERR_ARG if conn is not a TCP netconn
00432  */
00433 err_t
00434 netconn_recv_tcp_pbuf(struct netconn *conn, struct pbuf **new_buf)
00435 {
00436   LWIP_ERROR("netconn_recv: invalid conn", (conn != NULL) &&
00437              netconn_type(conn) == NETCONN_TCP, return ERR_ARG;);
00438 
00439   return netconn_recv_data(conn, (void **)new_buf);
00440 }
00441 
00442 /**
00443  * Receive data (in form of a netbuf containing a packet buffer) from a netconn
00444  *
00445  * @param conn the netconn from which to receive data
00446  * @param new_buf pointer where a new netbuf is stored when received data
00447  * @return ERR_OK if data has been received, an error code otherwise (timeout,
00448  *                memory error or another error)
00449  */
00450 err_t
00451 netconn_recv(struct netconn *conn, struct netbuf **new_buf)
00452 {
00453 #if LWIP_TCP
00454   struct netbuf *buf = NULL;
00455   err_t err;
00456 #endif /* LWIP_TCP */
00457 
00458   LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
00459   *new_buf = NULL;
00460   LWIP_ERROR("netconn_recv: invalid conn",    (conn != NULL),    return ERR_ARG;);
00461   LWIP_ERROR("netconn_accept: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);
00462 
00463 #if LWIP_TCP
00464   if (conn->type == NETCONN_TCP) {
00465     struct pbuf *p = NULL;
00466     /* This is not a listening netconn, since recvmbox is set */
00467 
00468     buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
00469     if (buf == NULL) {
00470       NETCONN_SET_SAFE_ERR(conn, ERR_MEM);
00471       return ERR_MEM;
00472     }
00473 
00474     err = netconn_recv_data(conn, (void **)&p);
00475     if (err != ERR_OK) {
00476       memp_free(MEMP_NETBUF, buf);
00477       return err;
00478     }
00479     LWIP_ASSERT("p != NULL", p != NULL);
00480 
00481     buf->p = p;
00482     buf->ptr = p;
00483     buf->port = 0;
00484     ip_addr_set_any(&buf->addr);
00485     *new_buf = buf;
00486     /* don't set conn->last_err: it's only ERR_OK, anyway */
00487     return ERR_OK;
00488   } else
00489 #endif /* LWIP_TCP */
00490   {
00491 #if (LWIP_UDP || LWIP_RAW)
00492     return netconn_recv_data(conn, (void **)new_buf);
00493 #endif /* (LWIP_UDP || LWIP_RAW) */
00494   }
00495 }
00496 
00497 /**
00498  * TCP: update the receive window: by calling this, the application
00499  * tells the stack that it has processed data and is able to accept
00500  * new data.
00501  * ATTENTION: use with care, this is mainly used for sockets!
00502  * Can only be used when calling netconn_set_noautorecved(conn, 1) before.
00503  *
00504  * @param conn the netconn for which to update the receive window
00505  * @param length amount of data processed (ATTENTION: this must be accurate!)
00506  */
00507 void
00508 netconn_recved(struct netconn *conn, u32_t length)
00509 {
00510 #if LWIP_TCP
00511   if ((conn != NULL) && (conn->type == NETCONN_TCP) &&
00512       (netconn_get_noautorecved(conn))) {
00513     struct api_msg msg;
00514     /* Let the stack know that we have taken the data. */
00515     /* TODO: Speedup: Don't block and wait for the answer here
00516        (to prevent multiple thread-switches). */
00517     msg.function = do_recv;
00518     msg.msg.conn = conn;
00519     msg.msg.msg.r.len = length;
00520     /* don't care for the return value of do_recv */
00521     TCPIP_APIMSG(&msg);
00522   }
00523 #else /* LWIP_TCP */
00524   LWIP_UNUSED_ARG(conn);
00525   LWIP_UNUSED_ARG(length);
00526 #endif /* LWIP_TCP */
00527 }
00528 
00529 /**
00530  * Send data (in form of a netbuf) to a specific remote IP address and port.
00531  * Only to be used for UDP and RAW netconns (not TCP).
00532  *
00533  * @param conn the netconn over which to send data
00534  * @param buf a netbuf containing the data to send
00535  * @param addr the remote IP address to which to send the data
00536  * @param port the remote port to which to send the data
00537  * @return ERR_OK if data was sent, any other err_t on error
00538  */
00539 err_t
00540 netconn_sendto(struct netconn *conn, struct netbuf *buf, ip_addr_t *addr, u16_t port)
00541 {
00542   if (buf != NULL) {
00543     ip_addr_set(&buf->addr, addr);
00544     buf->port = port;
00545     return netconn_send(conn, buf);
00546   }
00547   return ERR_VAL;
00548 }
00549 
00550 /**
00551  * Send data over a UDP or RAW netconn (that is already connected).
00552  *
00553  * @param conn the UDP or RAW netconn over which to send data
00554  * @param buf a netbuf containing the data to send
00555  * @return ERR_OK if data was sent, any other err_t on error
00556  */
00557 err_t
00558 netconn_send(struct netconn *conn, struct netbuf *buf)
00559 {
00560   struct api_msg msg;
00561   err_t err;
00562 
00563   LWIP_ERROR("netconn_send: invalid conn",  (conn != NULL), return ERR_ARG;);
00564 
00565   LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_send: sending %"U16_F" bytes\n", buf->p->tot_len));
00566   msg.function = do_send;
00567   msg.msg.conn = conn;
00568   msg.msg.msg.b = buf;
00569   err = TCPIP_APIMSG(&msg);
00570 
00571   NETCONN_SET_SAFE_ERR(conn, err);
00572   return err;
00573 }
00574 
00575 /**
00576  * Send data over a TCP netconn.
00577  *
00578  * @param conn the TCP netconn over which to send data
00579  * @param dataptr pointer to the application buffer that contains the data to send
00580  * @param size size of the application data to send
00581  * @param apiflags combination of following flags :
00582  * - NETCONN_COPY: data will be copied into memory belonging to the stack
00583  * - NETCONN_MORE: for TCP connection, PSH flag will be set on last segment sent
00584  * - NETCONN_DONTBLOCK: only write the data if all dat can be written at once
00585  * @return ERR_OK if data was sent, any other err_t on error
00586  */
00587 err_t
00588 netconn_write(struct netconn *conn, const void *dataptr, size_t size, u8_t apiflags)
00589 {
00590   struct api_msg msg;
00591   err_t err;
00592 
00593   LWIP_ERROR("netconn_write: invalid conn",  (conn != NULL), return ERR_ARG;);
00594   LWIP_ERROR("netconn_write: invalid conn->type",  (conn->type == NETCONN_TCP), return ERR_VAL;);
00595   if (size == 0) {
00596     return ERR_OK;
00597   }
00598 
00599   /* @todo: for non-blocking write, check if 'size' would ever fit into
00600             snd_queue or snd_buf */
00601   msg.function = do_write;
00602   msg.msg.conn = conn;
00603   msg.msg.msg.w.dataptr = dataptr;
00604   msg.msg.msg.w.apiflags = apiflags;
00605   msg.msg.msg.w.len = size;
00606   /* For locking the core: this _can_ be delayed on low memory/low send buffer,
00607      but if it is, this is done inside api_msg.c:do_write(), so we can use the
00608      non-blocking version here. */
00609   err = TCPIP_APIMSG(&msg);
00610 
00611   NETCONN_SET_SAFE_ERR(conn, err);
00612   return err;
00613 }
00614 
00615 /**
00616  * Close ot shutdown a TCP netconn (doesn't delete it).
00617  *
00618  * @param conn the TCP netconn to close or shutdown
00619  * @param how fully close or only shutdown one side?
00620  * @return ERR_OK if the netconn was closed, any other err_t on error
00621  */
00622 static err_t
00623 netconn_close_shutdown(struct netconn *conn, u8_t how)
00624 {
00625   struct api_msg msg;
00626   err_t err;
00627 
00628   LWIP_ERROR("netconn_close: invalid conn",  (conn != NULL), return ERR_ARG;);
00629 
00630   msg.function = do_close;
00631   msg.msg.conn = conn;
00632   /* shutting down both ends is the same as closing */
00633   msg.msg.msg.sd.shut = how;
00634   /* because of the LWIP_TCPIP_CORE_LOCKING implementation of do_close,
00635      don't use TCPIP_APIMSG here */
00636   err = tcpip_apimsg(&msg);
00637 
00638   NETCONN_SET_SAFE_ERR(conn, err);
00639   return err;
00640 }
00641 
00642 /**
00643  * Close a TCP netconn (doesn't delete it).
00644  *
00645  * @param conn the TCP netconn to close
00646  * @return ERR_OK if the netconn was closed, any other err_t on error
00647  */
00648 err_t
00649 netconn_close(struct netconn *conn)
00650 {
00651   /* shutting down both ends is the same as closing */
00652   return netconn_close_shutdown(conn, NETCONN_SHUT_RDWR);
00653 }
00654 
00655 /**
00656  * Shut down one or both sides of a TCP netconn (doesn't delete it).
00657  *
00658  * @param conn the TCP netconn to shut down
00659  * @return ERR_OK if the netconn was closed, any other err_t on error
00660  */
00661 err_t
00662 netconn_shutdown(struct netconn *conn, u8_t shut_rx, u8_t shut_tx)
00663 {
00664   return netconn_close_shutdown(conn, (shut_rx ? NETCONN_SHUT_RD : 0) | (shut_tx ? NETCONN_SHUT_WR : 0));
00665 }
00666 
00667 #if LWIP_IGMP
00668 /**
00669  * Join multicast groups for UDP netconns.
00670  *
00671  * @param conn the UDP netconn for which to change multicast addresses
00672  * @param multiaddr IP address of the multicast group to join or leave
00673  * @param netif_addr the IP address of the network interface on which to send
00674  *                  the igmp message
00675  * @param join_or_leave flag whether to send a join- or leave-message
00676  * @return ERR_OK if the action was taken, any err_t on error
00677  */
00678 err_t
00679 netconn_join_leave_group(struct netconn *conn,
00680                          ip_addr_t *multiaddr,
00681                          ip_addr_t *netif_addr,
00682                          enum netconn_igmp join_or_leave)
00683 {
00684   struct api_msg msg;
00685   err_t err;
00686 
00687   LWIP_ERROR("netconn_join_leave_group: invalid conn",  (conn != NULL), return ERR_ARG;);
00688 
00689   msg.function = do_join_leave_group;
00690   msg.msg.conn = conn;
00691   msg.msg.msg.jl.multiaddr = multiaddr;
00692   msg.msg.msg.jl.netif_addr = netif_addr;
00693   msg.msg.msg.jl.join_or_leave = join_or_leave;
00694   err = TCPIP_APIMSG(&msg);
00695 
00696   NETCONN_SET_SAFE_ERR(conn, err);
00697   return err;
00698 }
00699 #endif /* LWIP_IGMP */
00700 
00701 #if LWIP_DNS
00702 /**
00703  * Execute a DNS query, only one IP address is returned
00704  *
00705  * @param name a string representation of the DNS host name to query
00706  * @param addr a preallocated ip_addr_t where to store the resolved IP address
00707  * @return ERR_OK: resolving succeeded
00708  *         ERR_MEM: memory error, try again later
00709  *         ERR_ARG: dns client not initialized or invalid hostname
00710  *         ERR_VAL: dns server response was invalid
00711  */
00712 err_t
00713 netconn_gethostbyname(const char *name, ip_addr_t *addr)
00714 {
00715   struct dns_api_msg msg;
00716   err_t err;
00717   sys_sem_t sem;
00718 
00719   LWIP_ERROR("netconn_gethostbyname: invalid name", (name != NULL), return ERR_ARG;);
00720   LWIP_ERROR("netconn_gethostbyname: invalid addr", (addr != NULL), return ERR_ARG;);
00721 
00722   err = sys_sem_new(&sem, 0);
00723   if (err != ERR_OK) {
00724     return err;
00725   }
00726 
00727   msg.name = name;
00728   msg.addr = addr;
00729   msg.err = &err;
00730   msg.sem = &sem;
00731 
00732   tcpip_callback(do_gethostbyname, &msg);
00733   sys_sem_wait(&sem);
00734   sys_sem_free(&sem);
00735 
00736   return err;
00737 }
00738 #endif /* LWIP_DNS*/
00739 
00740 #endif /* LWIP_NETCONN */