lwip_api_lib.c

00001 /**
00002  * @file
00003  * Sequential API External module
00004  */
00005 
00006 /*
00007  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
00008  * All rights reserved.
00009  *
00010  * Redistribution and use in source and binary forms, with or without modification,
00011  * are permitted provided that the following conditions are met:
00012  *
00013  * 1. Redistributions of source code must retain the above copyright notice,
00014  *    this list of conditions and the following disclaimer.
00015  * 2. Redistributions in binary form must reproduce the above copyright notice,
00016  *    this list of conditions and the following disclaimer in the documentation
00017  *    and/or other materials provided with the distribution.
00018  * 3. The name of the author may not be used to endorse or promote products
00019  *    derived from this software without specific prior written permission.
00020  *
00021  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
00022  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
00023  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
00024  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00025  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
00026  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00027  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00028  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
00029  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
00030  * OF SUCH DAMAGE.
00031  *
00032  * This file is part of the lwIP TCP/IP stack.
00033  *
00034  * Author: Adam Dunkels <adam@sics.se>
00035  */
00036 
00037 /**
00038  * @defgroup netconn Netconn API
00039  * @ingroup threadsafe_api
00040  * Thread-safe, to be called from non-TCPIP threads only.
00041  * TX/RX handling based on @ref netbuf (containing @ref pbuf)
00042  * to avoid copying data around.
00043  * 
00044  * @defgroup netconn_common Common functions
00045  * @ingroup netconn
00046  * For use with TCP and UDP
00047  * 
00048  * @defgroup netconn_tcp TCP only
00049  * @ingroup netconn
00050  * TCP only functions
00051  * 
00052  * @defgroup netconn_udp UDP only
00053  * @ingroup netconn
00054  * UDP only functions
00055  */
00056 
00057 /* This is the part of the API that is linked with
00058    the application */
00059 
00060 #include "lwip/opt.h"
00061 
00062 #if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
00063 
00064 #include "lwip/api.h"
00065 #include "lwip/memp.h"
00066 
00067 #include "lwip/ip.h"
00068 #include "lwip/raw.h"
00069 #include "lwip/udp.h"
00070 #include "lwip/priv/api_msg.h"
00071 #include "lwip/priv/tcp_priv.h"
00072 #include "lwip/priv/tcpip_priv.h"
00073 
00074 #include <string.h>
00075 
00076 #define API_MSG_VAR_REF(name)               API_VAR_REF(name)
00077 #define API_MSG_VAR_DECLARE(name)           API_VAR_DECLARE(struct api_msg, name)
00078 #define API_MSG_VAR_ALLOC(name)             API_VAR_ALLOC(struct api_msg, MEMP_API_MSG, name, ERR_MEM)
00079 #define API_MSG_VAR_ALLOC_RETURN_NULL(name) API_VAR_ALLOC(struct api_msg, MEMP_API_MSG, name, NULL)
00080 #define API_MSG_VAR_FREE(name)              API_VAR_FREE(MEMP_API_MSG, name)
00081 
00082 static err_t netconn_close_shutdown(struct netconn *conn, u8_t how);
00083 
00084 /**
00085  * Call the lower part of a netconn_* function
00086  * This function is then running in the thread context
00087  * of tcpip_thread and has exclusive access to lwIP core code.
00088  *
00089  * @param fn function to call
00090  * @param apimsg a struct containing the function to call and its parameters
00091  * @return ERR_OK if the function was called, another err_t if not
00092  */
00093 static err_t
00094 netconn_apimsg(tcpip_callback_fn fn, struct api_msg *apimsg)
00095 {
00096   err_t err;
00097 
00098 #ifdef LWIP_DEBUG
00099   /* catch functions that don't set err */
00100   apimsg->err = ERR_VAL;
00101 #endif /* LWIP_DEBUG */
00102 
00103 #if LWIP_NETCONN_SEM_PER_THREAD
00104   apimsg->op_completed_sem = LWIP_NETCONN_THREAD_SEM_GET();
00105 #endif /* LWIP_NETCONN_SEM_PER_THREAD */
00106 
00107   err = tcpip_send_msg_wait_sem(fn, apimsg, LWIP_API_MSG_SEM(apimsg));
00108   if (err == ERR_OK) {
00109     return apimsg->err;
00110   }
00111   return err;
00112 }
00113 
00114 /**
00115  * Create a new netconn (of a specific type) that has a callback function.
00116  * The corresponding pcb is also created.
00117  *
00118  * @param t the type of 'connection' to create (@see enum netconn_type)
00119  * @param proto the IP protocol for RAW IP pcbs
00120  * @param callback a function to call on status changes (RX available, TX'ed)
00121  * @return a newly allocated struct netconn or
00122  *         NULL on memory error
00123  */
00124 struct netconn*
00125 netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto, netconn_callback callback)
00126 {
00127   struct netconn *conn;
00128   API_MSG_VAR_DECLARE(msg);
00129   API_MSG_VAR_ALLOC_RETURN_NULL(msg);
00130 
00131   conn = netconn_alloc(t, callback);
00132   if (conn != NULL) {
00133     err_t err;
00134 
00135     API_MSG_VAR_REF(msg).msg.n.proto = proto;
00136     API_MSG_VAR_REF(msg).conn = conn;
00137     err = netconn_apimsg(lwip_netconn_do_newconn, &API_MSG_VAR_REF(msg));
00138     if (err != ERR_OK) {
00139       LWIP_ASSERT("freeing conn without freeing pcb", conn->pcb.tcp == NULL);
00140       LWIP_ASSERT("conn has no recvmbox", sys_mbox_valid(&conn->recvmbox));
00141 #if LWIP_TCP
00142       LWIP_ASSERT("conn->acceptmbox shouldn't exist", !sys_mbox_valid(&conn->acceptmbox));
00143 #endif /* LWIP_TCP */
00144 #if !LWIP_NETCONN_SEM_PER_THREAD
00145       LWIP_ASSERT("conn has no op_completed", sys_sem_valid(&conn->op_completed));
00146       sys_sem_free(&conn->op_completed);
00147 #endif /* !LWIP_NETCONN_SEM_PER_THREAD */
00148       sys_mbox_free(&conn->recvmbox);
00149       memp_free(MEMP_NETCONN, conn);
00150       API_MSG_VAR_FREE(msg);
00151       return NULL;
00152     }
00153   }
00154   API_MSG_VAR_FREE(msg);
00155   return conn;
00156 }
00157 
00158 /**
00159  * @ingroup netconn_common
00160  * Close a netconn 'connection' and free its resources.
00161  * UDP and RAW connection are completely closed, TCP pcbs might still be in a waitstate
00162  * after this returns.
00163  *
00164  * @param conn the netconn to delete
00165  * @return ERR_OK if the connection was deleted
00166  */
00167 err_t
00168 netconn_delete(struct netconn *conn)
00169 {
00170   err_t err;
00171   API_MSG_VAR_DECLARE(msg);
00172 
00173   /* No ASSERT here because possible to get a (conn == NULL) if we got an accept error */
00174   if (conn == NULL) {
00175     return ERR_OK;
00176   }
00177 
00178   API_MSG_VAR_ALLOC(msg);
00179   API_MSG_VAR_REF(msg).conn = conn;
00180 #if LWIP_SO_SNDTIMEO || LWIP_SO_LINGER
00181   /* get the time we started, which is later compared to
00182      sys_now() + conn->send_timeout */
00183   API_MSG_VAR_REF(msg).msg.sd.time_started = sys_now();
00184 #else /* LWIP_SO_SNDTIMEO || LWIP_SO_LINGER */
00185 #if LWIP_TCP
00186   API_MSG_VAR_REF(msg).msg.sd.polls_left =
00187     ((LWIP_TCP_CLOSE_TIMEOUT_MS_DEFAULT + TCP_SLOW_INTERVAL - 1) / TCP_SLOW_INTERVAL) + 1;
00188 #endif /* LWIP_TCP */
00189 #endif /* LWIP_SO_SNDTIMEO || LWIP_SO_LINGER */
00190   err = netconn_apimsg(lwip_netconn_do_delconn, &API_MSG_VAR_REF(msg));
00191   API_MSG_VAR_FREE(msg);
00192 
00193   if (err != ERR_OK) {
00194     return err;
00195   }
00196 
00197   netconn_free(conn);
00198 
00199   return ERR_OK;
00200 }
00201 
00202 /**
00203  * Get the local or remote IP address and port of a netconn.
00204  * For RAW netconns, this returns the protocol instead of a port!
00205  *
00206  * @param conn the netconn to query
00207  * @param addr a pointer to which to save the IP address
00208  * @param port a pointer to which to save the port (or protocol for RAW)
00209  * @param local 1 to get the local IP address, 0 to get the remote one
00210  * @return ERR_CONN for invalid connections
00211  *         ERR_OK if the information was retrieved
00212  */
00213 err_t
00214 netconn_getaddr(struct netconn *conn, ip_addr_t *addr, u16_t *port, u8_t local)
00215 {
00216   API_MSG_VAR_DECLARE(msg);
00217   err_t err;
00218 
00219   LWIP_ERROR("netconn_getaddr: invalid conn", (conn != NULL), return ERR_ARG;);
00220   LWIP_ERROR("netconn_getaddr: invalid addr", (addr != NULL), return ERR_ARG;);
00221   LWIP_ERROR("netconn_getaddr: invalid port", (port != NULL), return ERR_ARG;);
00222 
00223   API_MSG_VAR_ALLOC(msg);
00224   API_MSG_VAR_REF(msg).conn = conn;
00225   API_MSG_VAR_REF(msg).msg.ad.local = local;
00226 #if LWIP_MPU_COMPATIBLE
00227   err = netconn_apimsg(lwip_netconn_do_getaddr, &API_MSG_VAR_REF(msg));
00228   *addr = msg->msg.ad.ipaddr;
00229   *port = msg->msg.ad.port;
00230 #else /* LWIP_MPU_COMPATIBLE */
00231   msg.msg.ad.ipaddr = addr;
00232   msg.msg.ad.port = port;
00233   err = netconn_apimsg(lwip_netconn_do_getaddr, &msg);
00234 #endif /* LWIP_MPU_COMPATIBLE */
00235   API_MSG_VAR_FREE(msg);
00236 
00237   return err;
00238 }
00239 
00240 /**
00241  * @ingroup netconn_common
00242  * Bind a netconn to a specific local IP address and port.
00243  * Binding one netconn twice might not always be checked correctly!
00244  *
00245  * @param conn the netconn to bind
00246  * @param addr the local IP address to bind the netconn to (use IP_ADDR_ANY
00247  *             to bind to all addresses)
00248  * @param port the local port to bind the netconn to (not used for RAW)
00249  * @return ERR_OK if bound, any other err_t on failure
00250  */
00251 err_t
00252 netconn_bind(struct netconn *conn, const ip_addr_t *addr, u16_t port)
00253 {
00254   API_MSG_VAR_DECLARE(msg);
00255   err_t err;
00256   
00257   LWIP_ERROR("netconn_bind: invalid conn", (conn != NULL), return ERR_ARG;);
00258 
00259   /* Don't propagate NULL pointer (IP_ADDR_ANY alias) to subsequent functions */
00260   if (addr == NULL) {
00261     addr = IP_ADDR_ANY;
00262   }
00263 
00264   API_MSG_VAR_ALLOC(msg);
00265   API_MSG_VAR_REF(msg).conn = conn;
00266   API_MSG_VAR_REF(msg).msg.bc.ipaddr = API_MSG_VAR_REF(addr);
00267   API_MSG_VAR_REF(msg).msg.bc.port = port;
00268   err = netconn_apimsg(lwip_netconn_do_bind, &API_MSG_VAR_REF(msg));
00269   API_MSG_VAR_FREE(msg);
00270 
00271   return err;
00272 }
00273 
00274 /**
00275  * @ingroup netconn_common
00276  * Connect a netconn to a specific remote IP address and port.
00277  *
00278  * @param conn the netconn to connect
00279  * @param addr the remote IP address to connect to
00280  * @param port the remote port to connect to (no used for RAW)
00281  * @return ERR_OK if connected, return value of tcp_/udp_/raw_connect otherwise
00282  */
00283 err_t
00284 netconn_connect(struct netconn *conn, const ip_addr_t *addr, u16_t port)
00285 {
00286   API_MSG_VAR_DECLARE(msg);
00287   err_t err;
00288 
00289   LWIP_ERROR("netconn_connect: invalid conn", (conn != NULL), return ERR_ARG;);
00290 
00291   /* Don't propagate NULL pointer (IP_ADDR_ANY alias) to subsequent functions */
00292   if (addr == NULL) {
00293     addr = IP_ADDR_ANY;
00294   }
00295 
00296   API_MSG_VAR_ALLOC(msg);
00297   API_MSG_VAR_REF(msg).conn = conn;
00298   API_MSG_VAR_REF(msg).msg.bc.ipaddr = API_MSG_VAR_REF(addr);
00299   API_MSG_VAR_REF(msg).msg.bc.port = port;
00300   err = netconn_apimsg(lwip_netconn_do_connect, &API_MSG_VAR_REF(msg));
00301   API_MSG_VAR_FREE(msg);
00302 
00303   return err;
00304 }
00305 
00306 /**
00307  * @ingroup netconn_udp
00308  * Disconnect a netconn from its current peer (only valid for UDP netconns).
00309  *
00310  * @param conn the netconn to disconnect
00311  * @return @todo: return value is not set here...
00312  */
00313 err_t
00314 netconn_disconnect(struct netconn *conn)
00315 {
00316   API_MSG_VAR_DECLARE(msg);
00317   err_t err;
00318 
00319   LWIP_ERROR("netconn_disconnect: invalid conn", (conn != NULL), return ERR_ARG;);
00320 
00321   API_MSG_VAR_ALLOC(msg);
00322   API_MSG_VAR_REF(msg).conn = conn;
00323   err = netconn_apimsg(lwip_netconn_do_disconnect, &API_MSG_VAR_REF(msg));
00324   API_MSG_VAR_FREE(msg);
00325 
00326   return err;
00327 }
00328 
00329 /**
00330  * @ingroup netconn_tcp
00331  * Set a TCP netconn into listen mode
00332  *
00333  * @param conn the tcp netconn to set to listen mode
00334  * @param backlog the listen backlog, only used if TCP_LISTEN_BACKLOG==1
00335  * @return ERR_OK if the netconn was set to listen (UDP and RAW netconns
00336  *         don't return any error (yet?))
00337  */
00338 err_t
00339 netconn_listen_with_backlog(struct netconn *conn, u8_t backlog)
00340 {
00341 #if LWIP_TCP
00342   API_MSG_VAR_DECLARE(msg);
00343   err_t err;
00344 
00345   /* This does no harm. If TCP_LISTEN_BACKLOG is off, backlog is unused. */
00346   LWIP_UNUSED_ARG(backlog);
00347 
00348   LWIP_ERROR("netconn_listen: invalid conn", (conn != NULL), return ERR_ARG;);
00349 
00350   API_MSG_VAR_ALLOC(msg);
00351   API_MSG_VAR_REF(msg).conn = conn;
00352 #if TCP_LISTEN_BACKLOG
00353   API_MSG_VAR_REF(msg).msg.lb.backlog = backlog;
00354 #endif /* TCP_LISTEN_BACKLOG */
00355   err = netconn_apimsg(lwip_netconn_do_listen, &API_MSG_VAR_REF(msg));
00356   API_MSG_VAR_FREE(msg);
00357 
00358   return err;
00359 #else /* LWIP_TCP */
00360   LWIP_UNUSED_ARG(conn);
00361   LWIP_UNUSED_ARG(backlog);
00362   return ERR_ARG;
00363 #endif /* LWIP_TCP */
00364 }
00365 
00366 /**
00367  * @ingroup netconn_tcp
00368  * Accept a new connection on a TCP listening netconn.
00369  *
00370  * @param conn the TCP listen netconn
00371  * @param new_conn pointer where the new connection is stored
00372  * @return ERR_OK if a new connection has been received or an error
00373  *                code otherwise
00374  */
00375 err_t
00376 netconn_accept(struct netconn *conn, struct netconn **new_conn)
00377 {
00378 #if LWIP_TCP
00379   void *accept_ptr;
00380   struct netconn *newconn;
00381   err_t err;
00382 #if TCP_LISTEN_BACKLOG
00383   API_MSG_VAR_DECLARE(msg);
00384 #endif /* TCP_LISTEN_BACKLOG */
00385 
00386   LWIP_ERROR("netconn_accept: invalid pointer",    (new_conn != NULL),                  return ERR_ARG;);
00387   *new_conn = NULL;
00388   LWIP_ERROR("netconn_accept: invalid conn",       (conn != NULL),                      return ERR_ARG;);
00389 
00390   err = conn->last_err;
00391   if (ERR_IS_FATAL(err)) {
00392     /* don't recv on fatal errors: this might block the application task
00393        waiting on acceptmbox forever! */
00394     return err;
00395   }
00396   if (!sys_mbox_valid(&conn->acceptmbox)) {
00397     return ERR_CLSD;
00398   }
00399 
00400 #if TCP_LISTEN_BACKLOG
00401   API_MSG_VAR_ALLOC(msg);
00402 #endif /* TCP_LISTEN_BACKLOG */
00403 
00404 #if LWIP_SO_RCVTIMEO
00405   if (sys_arch_mbox_fetch(&conn->acceptmbox, &accept_ptr, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
00406 #if TCP_LISTEN_BACKLOG
00407     API_MSG_VAR_FREE(msg);
00408 #endif /* TCP_LISTEN_BACKLOG */
00409     return ERR_TIMEOUT;
00410   }
00411 #else
00412   sys_arch_mbox_fetch(&conn->acceptmbox, &accept_ptr, 0);
00413 #endif /* LWIP_SO_RCVTIMEO*/
00414   newconn = (struct netconn *)accept_ptr;
00415   /* Register event with callback */
00416   API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
00417 
00418   if (accept_ptr == &netconn_aborted) {
00419     /* a connection has been aborted: out of pcbs or out of netconns during accept */
00420     /* @todo: set netconn error, but this would be fatal and thus block further accepts */
00421 #if TCP_LISTEN_BACKLOG
00422     API_MSG_VAR_FREE(msg);
00423 #endif /* TCP_LISTEN_BACKLOG */
00424     return ERR_ABRT;
00425   }
00426   if (newconn == NULL) {
00427     /* connection has been aborted */
00428     /* in this special case, we set the netconn error from application thread, as
00429        on a ready-to-accept listening netconn, there should not be anything running
00430        in tcpip_thread */
00431     NETCONN_SET_SAFE_ERR(conn, ERR_CLSD);
00432 #if TCP_LISTEN_BACKLOG
00433     API_MSG_VAR_FREE(msg);
00434 #endif /* TCP_LISTEN_BACKLOG */
00435     return ERR_CLSD;
00436   }
00437 #if TCP_LISTEN_BACKLOG
00438   /* Let the stack know that we have accepted the connection. */
00439   API_MSG_VAR_REF(msg).conn = newconn;
00440   /* don't care for the return value of lwip_netconn_do_recv */
00441   netconn_apimsg(lwip_netconn_do_accepted, &API_MSG_VAR_REF(msg));
00442   API_MSG_VAR_FREE(msg);
00443 #endif /* TCP_LISTEN_BACKLOG */
00444 
00445   *new_conn = newconn;
00446   /* don't set conn->last_err: it's only ERR_OK, anyway */
00447   return ERR_OK;
00448 #else /* LWIP_TCP */
00449   LWIP_UNUSED_ARG(conn);
00450   LWIP_UNUSED_ARG(new_conn);
00451   return ERR_ARG;
00452 #endif /* LWIP_TCP */
00453 }
00454 
00455 /**
00456  * @ingroup netconn_common
00457  * Receive data: actual implementation that doesn't care whether pbuf or netbuf
00458  * is received
00459  *
00460  * @param conn the netconn from which to receive data
00461  * @param new_buf pointer where a new pbuf/netbuf is stored when received data
00462  * @return ERR_OK if data has been received, an error code otherwise (timeout,
00463  *                memory error or another error)
00464  */
00465 static err_t
00466 netconn_recv_data(struct netconn *conn, void **new_buf)
00467 {
00468   void *buf = NULL;
00469   u16_t len;
00470   err_t err;
00471 #if LWIP_TCP
00472   API_MSG_VAR_DECLARE(msg);
00473 #if LWIP_MPU_COMPATIBLE
00474   msg = NULL;
00475 #endif
00476 #endif /* LWIP_TCP */
00477 
00478   LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
00479   *new_buf = NULL;
00480   LWIP_ERROR("netconn_recv: invalid conn",    (conn != NULL),    return ERR_ARG;);
00481 #if LWIP_TCP
00482 #if (LWIP_UDP || LWIP_RAW)
00483   if (NETCONNTYPE_GROUP(conn->type) == NETCONN_TCP)
00484 #endif /* (LWIP_UDP || LWIP_RAW) */
00485   {
00486     if (!sys_mbox_valid(&conn->recvmbox)) {
00487       /* This happens when calling this function after receiving FIN */
00488       return sys_mbox_valid(&conn->acceptmbox) ? ERR_CONN : ERR_CLSD;
00489     }
00490   }
00491 #endif /* LWIP_TCP */
00492   LWIP_ERROR("netconn_recv: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);
00493 
00494   err = conn->last_err;
00495   if (ERR_IS_FATAL(err)) {
00496     /* don't recv on fatal errors: this might block the application task
00497        waiting on recvmbox forever! */
00498     /* @todo: this does not allow us to fetch data that has been put into recvmbox
00499        before the fatal error occurred - is that a problem? */
00500     return err;
00501   }
00502 #if LWIP_TCP
00503 #if (LWIP_UDP || LWIP_RAW)
00504   if (NETCONNTYPE_GROUP(conn->type) == NETCONN_TCP)
00505 #endif /* (LWIP_UDP || LWIP_RAW) */
00506   {
00507     API_MSG_VAR_ALLOC(msg);
00508   }
00509 #endif /* LWIP_TCP */
00510 
00511 #if LWIP_SO_RCVTIMEO
00512   if (sys_arch_mbox_fetch(&conn->recvmbox, &buf, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
00513 #if LWIP_TCP
00514 #if (LWIP_UDP || LWIP_RAW)
00515     if (NETCONNTYPE_GROUP(conn->type) == NETCONN_TCP)
00516 #endif /* (LWIP_UDP || LWIP_RAW) */
00517     {
00518       API_MSG_VAR_FREE(msg);
00519     }
00520 #endif /* LWIP_TCP */
00521     return ERR_TIMEOUT;
00522   }
00523 #else
00524   sys_arch_mbox_fetch(&conn->recvmbox, &buf, 0);
00525 #endif /* LWIP_SO_RCVTIMEO*/
00526 
00527 #if LWIP_TCP
00528 #if (LWIP_UDP || LWIP_RAW)
00529   if (NETCONNTYPE_GROUP(conn->type) == NETCONN_TCP)
00530 #endif /* (LWIP_UDP || LWIP_RAW) */
00531   {
00532     /* Let the stack know that we have taken the data. */
00533     /* @todo: Speedup: Don't block and wait for the answer here
00534        (to prevent multiple thread-switches). */
00535     API_MSG_VAR_REF(msg).conn = conn;
00536     if (buf != NULL) {
00537       API_MSG_VAR_REF(msg).msg.r.len = ((struct pbuf *)buf)->tot_len;
00538     } else {
00539       API_MSG_VAR_REF(msg).msg.r.len = 1;
00540     }
00541 
00542     /* don't care for the return value of lwip_netconn_do_recv */
00543     netconn_apimsg(lwip_netconn_do_recv, &API_MSG_VAR_REF(msg));
00544     API_MSG_VAR_FREE(msg);
00545 
00546     /* If we are closed, we indicate that we no longer wish to use the socket */
00547     if (buf == NULL) {
00548       API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
00549       /* RX side is closed, so deallocate the recvmbox */
00550       netconn_close_shutdown(conn, NETCONN_SHUT_RD);
00551       /* Don' store ERR_CLSD as conn->err since we are only half-closed */
00552       return ERR_CLSD;
00553     }
00554     len = ((struct pbuf *)buf)->tot_len;
00555   }
00556 #endif /* LWIP_TCP */
00557 #if LWIP_TCP && (LWIP_UDP || LWIP_RAW)
00558   else
00559 #endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
00560 #if (LWIP_UDP || LWIP_RAW)
00561   {
00562     LWIP_ASSERT("buf != NULL", buf != NULL);
00563     len = netbuf_len((struct netbuf *)buf);
00564   }
00565 #endif /* (LWIP_UDP || LWIP_RAW) */
00566 
00567 #if LWIP_SO_RCVBUF
00568   SYS_ARCH_DEC(conn->recv_avail, len);
00569 #endif /* LWIP_SO_RCVBUF */
00570   /* Register event with callback */
00571   API_EVENT(conn, NETCONN_EVT_RCVMINUS, len);
00572 
00573   LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_recv_data: received %p, len=%"U16_F"\n", buf, len));
00574 
00575   *new_buf = buf;
00576   /* don't set conn->last_err: it's only ERR_OK, anyway */
00577   return ERR_OK;
00578 }
00579 
00580 /**
00581  * @ingroup netconn_tcp
00582  * Receive data (in form of a pbuf) from a TCP netconn
00583  *
00584  * @param conn the netconn from which to receive data
00585  * @param new_buf pointer where a new pbuf is stored when received data
00586  * @return ERR_OK if data has been received, an error code otherwise (timeout,
00587  *                memory error or another error)
00588  *         ERR_ARG if conn is not a TCP netconn
00589  */
00590 err_t
00591 netconn_recv_tcp_pbuf(struct netconn *conn, struct pbuf **new_buf)
00592 {
00593   LWIP_ERROR("netconn_recv: invalid conn", (conn != NULL) &&
00594              NETCONNTYPE_GROUP(netconn_type(conn)) == NETCONN_TCP, return ERR_ARG;);
00595 
00596   return netconn_recv_data(conn, (void **)new_buf);
00597 }
00598 
00599 /**
00600  * @ingroup netconn_common
00601  * Receive data (in form of a netbuf containing a packet buffer) from a netconn
00602  *
00603  * @param conn the netconn from which to receive data
00604  * @param new_buf pointer where a new netbuf is stored when received data
00605  * @return ERR_OK if data has been received, an error code otherwise (timeout,
00606  *                memory error or another error)
00607  */
00608 err_t
00609 netconn_recv(struct netconn *conn, struct netbuf **new_buf)
00610 {
00611 #if LWIP_TCP
00612   struct netbuf *buf = NULL;
00613   err_t err;
00614 #endif /* LWIP_TCP */
00615 
00616   LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
00617   *new_buf = NULL;
00618   LWIP_ERROR("netconn_recv: invalid conn",    (conn != NULL),    return ERR_ARG;);
00619 
00620 #if LWIP_TCP
00621 #if (LWIP_UDP || LWIP_RAW)
00622   if (NETCONNTYPE_GROUP(conn->type) == NETCONN_TCP)
00623 #endif /* (LWIP_UDP || LWIP_RAW) */
00624   {
00625     struct pbuf *p = NULL;
00626     /* This is not a listening netconn, since recvmbox is set */
00627 
00628     buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
00629     if (buf == NULL) {
00630       return ERR_MEM;
00631     }
00632 
00633     err = netconn_recv_data(conn, (void **)&p);
00634     if (err != ERR_OK) {
00635       memp_free(MEMP_NETBUF, buf);
00636       return err;
00637     }
00638     LWIP_ASSERT("p != NULL", p != NULL);
00639 
00640     buf->p = p;
00641     buf->ptr = p;
00642     buf->port = 0;
00643     ip_addr_set_zero(&buf->addr);
00644     *new_buf = buf;
00645     /* don't set conn->last_err: it's only ERR_OK, anyway */
00646     return ERR_OK;
00647   }
00648 #endif /* LWIP_TCP */
00649 #if LWIP_TCP && (LWIP_UDP || LWIP_RAW)
00650   else
00651 #endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
00652   {
00653 #if (LWIP_UDP || LWIP_RAW)
00654     return netconn_recv_data(conn, (void **)new_buf);
00655 #endif /* (LWIP_UDP || LWIP_RAW) */
00656   }
00657 }
00658 
00659 /**
00660  * @ingroup netconn_udp
00661  * Send data (in form of a netbuf) to a specific remote IP address and port.
00662  * Only to be used for UDP and RAW netconns (not TCP).
00663  *
00664  * @param conn the netconn over which to send data
00665  * @param buf a netbuf containing the data to send
00666  * @param addr the remote IP address to which to send the data
00667  * @param port the remote port to which to send the data
00668  * @return ERR_OK if data was sent, any other err_t on error
00669  */
00670 err_t
00671 netconn_sendto(struct netconn *conn, struct netbuf *buf, const ip_addr_t *addr, u16_t port)
00672 {
00673   if (buf != NULL) {
00674     ip_addr_set(&buf->addr, addr);
00675     buf->port = port;
00676     return netconn_send(conn, buf);
00677   }
00678   return ERR_VAL;
00679 }
00680 
00681 /**
00682  * @ingroup netconn_udp
00683  * Send data over a UDP or RAW netconn (that is already connected).
00684  *
00685  * @param conn the UDP or RAW netconn over which to send data
00686  * @param buf a netbuf containing the data to send
00687  * @return ERR_OK if data was sent, any other err_t on error
00688  */
00689 err_t
00690 netconn_send(struct netconn *conn, struct netbuf *buf)
00691 {
00692   API_MSG_VAR_DECLARE(msg);
00693   err_t err;
00694 
00695   LWIP_ERROR("netconn_send: invalid conn",  (conn != NULL), return ERR_ARG;);
00696 
00697   LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_send: sending %"U16_F" bytes\n", buf->p->tot_len));
00698   API_MSG_VAR_ALLOC(msg);
00699   API_MSG_VAR_REF(msg).conn = conn;
00700   API_MSG_VAR_REF(msg).msg.b = buf;
00701   err = netconn_apimsg(lwip_netconn_do_send, &API_MSG_VAR_REF(msg));
00702   API_MSG_VAR_FREE(msg);
00703 
00704   return err;
00705 }
00706 
00707 /**
00708  * @ingroup netconn_tcp
00709  * Send data over a TCP netconn.
00710  *
00711  * @param conn the TCP netconn over which to send data
00712  * @param dataptr pointer to the application buffer that contains the data to send
00713  * @param size size of the application data to send
00714  * @param apiflags combination of following flags :
00715  * - NETCONN_COPY: data will be copied into memory belonging to the stack
00716  * - NETCONN_MORE: for TCP connection, PSH flag will be set on last segment sent
00717  * - NETCONN_DONTBLOCK: only write the data if all data can be written at once
00718  * @param bytes_written pointer to a location that receives the number of written bytes
00719  * @return ERR_OK if data was sent, any other err_t on error
00720  */
00721 err_t
00722 netconn_write_partly(struct netconn *conn, const void *dataptr, size_t size,
00723                      u8_t apiflags, size_t *bytes_written)
00724 {
00725   API_MSG_VAR_DECLARE(msg);
00726   err_t err;
00727   u8_t dontblock;
00728 
00729   LWIP_ERROR("netconn_write: invalid conn",  (conn != NULL), return ERR_ARG;);
00730   LWIP_ERROR("netconn_write: invalid conn->type",  (NETCONNTYPE_GROUP(conn->type)== NETCONN_TCP), return ERR_VAL;);
00731   if (size == 0) {
00732     return ERR_OK;
00733   }
00734   dontblock = netconn_is_nonblocking(conn) || (apiflags & NETCONN_DONTBLOCK);
00735   if (dontblock && !bytes_written) {
00736     /* This implies netconn_write() cannot be used for non-blocking send, since
00737        it has no way to return the number of bytes written. */
00738     return ERR_VAL;
00739   }
00740 
00741   API_MSG_VAR_ALLOC(msg);
00742   /* non-blocking write sends as much  */
00743   API_MSG_VAR_REF(msg).conn = conn;
00744   API_MSG_VAR_REF(msg).msg.w.dataptr = dataptr;
00745   API_MSG_VAR_REF(msg).msg.w.apiflags = apiflags;
00746   API_MSG_VAR_REF(msg).msg.w.len = size;
00747 #if LWIP_SO_SNDTIMEO
00748   if (conn->send_timeout != 0) {
00749     /* get the time we started, which is later compared to
00750         sys_now() + conn->send_timeout */
00751     API_MSG_VAR_REF(msg).msg.w.time_started = sys_now();
00752   } else {
00753     API_MSG_VAR_REF(msg).msg.w.time_started = 0;
00754   }
00755 #endif /* LWIP_SO_SNDTIMEO */
00756 
00757   /* For locking the core: this _can_ be delayed on low memory/low send buffer,
00758      but if it is, this is done inside api_msg.c:do_write(), so we can use the
00759      non-blocking version here. */
00760   err = netconn_apimsg(lwip_netconn_do_write, &API_MSG_VAR_REF(msg));
00761   if ((err == ERR_OK) && (bytes_written != NULL)) {
00762     if (dontblock
00763 #if LWIP_SO_SNDTIMEO
00764         || (conn->send_timeout != 0)
00765 #endif /* LWIP_SO_SNDTIMEO */
00766        ) {
00767       /* nonblocking write: maybe the data has been sent partly */
00768       *bytes_written = API_MSG_VAR_REF(msg).msg.w.len;
00769     } else {
00770       /* blocking call succeeded: all data has been sent if it */
00771       *bytes_written = size;
00772     }
00773   }
00774   API_MSG_VAR_FREE(msg);
00775 
00776   return err;
00777 }
00778 
00779 /**
00780  * @ingroup netconn_tcp
00781  * Close or shutdown a TCP netconn (doesn't delete it).
00782  *
00783  * @param conn the TCP netconn to close or shutdown
00784  * @param how fully close or only shutdown one side?
00785  * @return ERR_OK if the netconn was closed, any other err_t on error
00786  */
00787 static err_t
00788 netconn_close_shutdown(struct netconn *conn, u8_t how)
00789 {
00790   API_MSG_VAR_DECLARE(msg);
00791   err_t err;
00792   LWIP_UNUSED_ARG(how);
00793 
00794   LWIP_ERROR("netconn_close: invalid conn",  (conn != NULL), return ERR_ARG;);
00795 
00796   API_MSG_VAR_ALLOC(msg);
00797   API_MSG_VAR_REF(msg).conn = conn;
00798 #if LWIP_TCP
00799   /* shutting down both ends is the same as closing */
00800   API_MSG_VAR_REF(msg).msg.sd.shut = how;
00801 #if LWIP_SO_SNDTIMEO || LWIP_SO_LINGER
00802   /* get the time we started, which is later compared to
00803      sys_now() + conn->send_timeout */
00804   API_MSG_VAR_REF(msg).msg.sd.time_started = sys_now();
00805 #else /* LWIP_SO_SNDTIMEO || LWIP_SO_LINGER */
00806   API_MSG_VAR_REF(msg).msg.sd.polls_left =
00807     ((LWIP_TCP_CLOSE_TIMEOUT_MS_DEFAULT + TCP_SLOW_INTERVAL - 1) / TCP_SLOW_INTERVAL) + 1;
00808 #endif /* LWIP_SO_SNDTIMEO || LWIP_SO_LINGER */
00809 #endif /* LWIP_TCP */
00810   err = netconn_apimsg(lwip_netconn_do_close, &API_MSG_VAR_REF(msg));
00811   API_MSG_VAR_FREE(msg);
00812 
00813   return err;
00814 }
00815 
00816 /**
00817  * @ingroup netconn_tcp
00818  * Close a TCP netconn (doesn't delete it).
00819  *
00820  * @param conn the TCP netconn to close
00821  * @return ERR_OK if the netconn was closed, any other err_t on error
00822  */
00823 err_t
00824 netconn_close(struct netconn *conn)
00825 {
00826   /* shutting down both ends is the same as closing */
00827   return netconn_close_shutdown(conn, NETCONN_SHUT_RDWR);
00828 }
00829 
00830 /**
00831  * @ingroup netconn_tcp
00832  * Shut down one or both sides of a TCP netconn (doesn't delete it).
00833  *
00834  * @param conn the TCP netconn to shut down
00835  * @param shut_rx shut down the RX side (no more read possible after this)
00836  * @param shut_tx shut down the TX side (no more write possible after this)
00837  * @return ERR_OK if the netconn was closed, any other err_t on error
00838  */
00839 err_t
00840 netconn_shutdown(struct netconn *conn, u8_t shut_rx, u8_t shut_tx)
00841 {
00842   return netconn_close_shutdown(conn, (shut_rx ? NETCONN_SHUT_RD : 0) | (shut_tx ? NETCONN_SHUT_WR : 0));
00843 }
00844 
00845 #if LWIP_IGMP || (LWIP_IPV6 && LWIP_IPV6_MLD)
00846 /**
00847  * @ingroup netconn_udp
00848  * Join multicast groups for UDP netconns.
00849  *
00850  * @param conn the UDP netconn for which to change multicast addresses
00851  * @param multiaddr IP address of the multicast group to join or leave
00852  * @param netif_addr the IP address of the network interface on which to send
00853  *                  the igmp message
00854  * @param join_or_leave flag whether to send a join- or leave-message
00855  * @return ERR_OK if the action was taken, any err_t on error
00856  */
00857 err_t
00858 netconn_join_leave_group(struct netconn *conn,
00859                          const ip_addr_t *multiaddr,
00860                          const ip_addr_t *netif_addr,
00861                          enum netconn_igmp join_or_leave)
00862 {
00863   API_MSG_VAR_DECLARE(msg);
00864   err_t err;
00865 
00866   LWIP_ERROR("netconn_join_leave_group: invalid conn",  (conn != NULL), return ERR_ARG;);
00867 
00868   API_MSG_VAR_ALLOC(msg);
00869 
00870   /* Don't propagate NULL pointer (IP_ADDR_ANY alias) to subsequent functions */
00871   if (multiaddr == NULL) {
00872     multiaddr = IP_ADDR_ANY;
00873   }
00874   if (netif_addr == NULL) {
00875     netif_addr = IP_ADDR_ANY;
00876   }
00877 
00878   API_MSG_VAR_REF(msg).conn = conn;
00879   API_MSG_VAR_REF(msg).msg.jl.multiaddr = API_MSG_VAR_REF(multiaddr);
00880   API_MSG_VAR_REF(msg).msg.jl.netif_addr = API_MSG_VAR_REF(netif_addr);
00881   API_MSG_VAR_REF(msg).msg.jl.join_or_leave = join_or_leave;
00882   err = netconn_apimsg(lwip_netconn_do_join_leave_group, &API_MSG_VAR_REF(msg));
00883   API_MSG_VAR_FREE(msg);
00884 
00885   return err;
00886 }
00887 #endif /* LWIP_IGMP || (LWIP_IPV6 && LWIP_IPV6_MLD) */
00888 
00889 #if LWIP_DNS
00890 /**
00891  * @ingroup netconn_common
00892  * Execute a DNS query, only one IP address is returned
00893  *
00894  * @param name a string representation of the DNS host name to query
00895  * @param addr a preallocated ip_addr_t where to store the resolved IP address
00896  * @param dns_addrtype IP address type (IPv4 / IPv6)
00897  * @return ERR_OK: resolving succeeded
00898  *         ERR_MEM: memory error, try again later
00899  *         ERR_ARG: dns client not initialized or invalid hostname
00900  *         ERR_VAL: dns server response was invalid
00901  */
00902 #if LWIP_IPV4 && LWIP_IPV6
00903 err_t
00904 netconn_gethostbyname_addrtype(const char *name, ip_addr_t *addr, u8_t dns_addrtype)
00905 #else
00906 err_t
00907 netconn_gethostbyname(const char *name, ip_addr_t *addr)
00908 #endif
00909 {
00910   API_VAR_DECLARE(struct dns_api_msg, msg);
00911 #if !LWIP_MPU_COMPATIBLE
00912   sys_sem_t sem;
00913 #endif /* LWIP_MPU_COMPATIBLE */
00914   err_t err;
00915 
00916   LWIP_ERROR("netconn_gethostbyname: invalid name", (name != NULL), return ERR_ARG;);
00917   LWIP_ERROR("netconn_gethostbyname: invalid addr", (addr != NULL), return ERR_ARG;);
00918 #if LWIP_MPU_COMPATIBLE
00919   if (strlen(name) >= DNS_MAX_NAME_LENGTH) {
00920     return ERR_ARG;
00921   }
00922 #endif
00923 
00924   API_VAR_ALLOC(struct dns_api_msg, MEMP_DNS_API_MSG, msg, ERR_MEM);
00925 #if LWIP_MPU_COMPATIBLE
00926   strncpy(API_VAR_REF(msg).name, name, DNS_MAX_NAME_LENGTH-1);
00927   API_VAR_REF(msg).name[DNS_MAX_NAME_LENGTH-1] = 0;
00928 #else /* LWIP_MPU_COMPATIBLE */
00929   msg.err = &err;
00930   msg.sem = &sem;
00931   API_VAR_REF(msg).addr = API_VAR_REF(addr);
00932   API_VAR_REF(msg).name = name;
00933 #endif /* LWIP_MPU_COMPATIBLE */
00934 #if LWIP_IPV4 && LWIP_IPV6
00935   API_VAR_REF(msg).dns_addrtype = dns_addrtype;
00936 #endif /* LWIP_IPV4 && LWIP_IPV6 */
00937 #if LWIP_NETCONN_SEM_PER_THREAD
00938   API_VAR_REF(msg).sem = LWIP_NETCONN_THREAD_SEM_GET();
00939 #else /* LWIP_NETCONN_SEM_PER_THREAD*/
00940   err = sys_sem_new(API_EXPR_REF(API_VAR_REF(msg).sem), 0);
00941   if (err != ERR_OK) {
00942     API_VAR_FREE(MEMP_DNS_API_MSG, msg);
00943     return err;
00944   }
00945 #endif /* LWIP_NETCONN_SEM_PER_THREAD */
00946 
00947   err = tcpip_callback(lwip_netconn_do_gethostbyname, &API_VAR_REF(msg));
00948   if (err != ERR_OK) {
00949 #if !LWIP_NETCONN_SEM_PER_THREAD
00950     sys_sem_free(API_EXPR_REF(API_VAR_REF(msg).sem));
00951 #endif /* !LWIP_NETCONN_SEM_PER_THREAD */
00952     API_VAR_FREE(MEMP_DNS_API_MSG, msg);
00953     return err;
00954   }
00955   sys_sem_wait(API_EXPR_REF_SEM(API_VAR_REF(msg).sem));
00956 #if !LWIP_NETCONN_SEM_PER_THREAD
00957   sys_sem_free(API_EXPR_REF(API_VAR_REF(msg).sem));
00958 #endif /* !LWIP_NETCONN_SEM_PER_THREAD */
00959 
00960 #if LWIP_MPU_COMPATIBLE
00961   *addr = msg->addr;
00962   err = msg->err;
00963 #endif /* LWIP_MPU_COMPATIBLE */
00964 
00965   API_VAR_FREE(MEMP_DNS_API_MSG, msg);
00966   return err;
00967 }
00968 #endif /* LWIP_DNS*/
00969 
00970 #if LWIP_NETCONN_SEM_PER_THREAD
00971 void
00972 netconn_thread_init(void)
00973 {
00974   sys_sem_t *sem = LWIP_NETCONN_THREAD_SEM_GET();
00975   if ((sem == NULL) || !sys_sem_valid(sem)) {
00976     /* call alloc only once */
00977     LWIP_NETCONN_THREAD_SEM_ALLOC();
00978     LWIP_ASSERT("LWIP_NETCONN_THREAD_SEM_ALLOC() failed", sys_sem_valid(LWIP_NETCONN_THREAD_SEM_GET()));
00979   }
00980 }
00981 
00982 void
00983 netconn_thread_cleanup(void)
00984 {
00985   sys_sem_t *sem = LWIP_NETCONN_THREAD_SEM_GET();
00986   if ((sem != NULL) && sys_sem_valid(sem)) {
00987     /* call free only once */
00988     LWIP_NETCONN_THREAD_SEM_FREE();
00989   }
00990 }
00991 #endif /* LWIP_NETCONN_SEM_PER_THREAD */
00992 
00993 #endif /* LWIP_NETCONN */