api_msg.c

00001 /**
00002  * @file
00003  * Sequential API Internal 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 #include "lwip/opt.h"
00040 
00041 #if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
00042 
00043 #include "lwip/api_msg.h"
00044 
00045 #include "lwip/ip.h"
00046 #include "lwip/udp.h"
00047 #include "lwip/tcp.h"
00048 #include "lwip/raw.h"
00049 
00050 #include "lwip/memp.h"
00051 #include "lwip/tcpip.h"
00052 #include "lwip/igmp.h"
00053 #include "lwip/dns.h"
00054 
00055 #include <string.h>
00056 
00057 #define SET_NONBLOCKING_CONNECT(conn, val)  do { if(val) { \
00058   (conn)->flags |= NETCONN_FLAG_IN_NONBLOCKING_CONNECT; \
00059 } else { \
00060   (conn)->flags &= ~ NETCONN_FLAG_IN_NONBLOCKING_CONNECT; }} while(0)
00061 #define IN_NONBLOCKING_CONNECT(conn) (((conn)->flags & NETCONN_FLAG_IN_NONBLOCKING_CONNECT) != 0)
00062 
00063 /* forward declarations */
00064 #if LWIP_TCP
00065 static err_t do_writemore(struct netconn *conn);
00066 static void do_close_internal(struct netconn *conn);
00067 #endif
00068 
00069 #if LWIP_RAW
00070 /**
00071  * Receive callback function for RAW netconns.
00072  * Doesn't 'eat' the packet, only references it and sends it to
00073  * conn->recvmbox
00074  *
00075  * @see raw.h (struct raw_pcb.recv) for parameters and return value
00076  */
00077 static u8_t
00078 recv_raw(void *arg, struct raw_pcb *pcb, struct pbuf *p,
00079     ip_addr_t *addr)
00080 {
00081   struct pbuf *q;
00082   struct netbuf *buf;
00083   struct netconn *conn;
00084 
00085   LWIP_UNUSED_ARG(addr);
00086   conn = (struct netconn *)arg;
00087 
00088   if ((conn != NULL) && sys_mbox_valid(&conn->recvmbox)) {
00089 #if LWIP_SO_RCVBUF
00090     int recv_avail;
00091     SYS_ARCH_GET(conn->recv_avail, recv_avail);
00092     if ((recv_avail + (int)(p->tot_len)) > conn->recv_bufsize) {
00093       return 0;
00094     }
00095 #endif /* LWIP_SO_RCVBUF */
00096     /* copy the whole packet into new pbufs */
00097     q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
00098     if(q != NULL) {
00099       if (pbuf_copy(q, p) != ERR_OK) {
00100         pbuf_free(q);
00101         q = NULL;
00102       }
00103     }
00104 
00105     if (q != NULL) {
00106       u16_t len;
00107       buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
00108       if (buf == NULL) {
00109         pbuf_free(q);
00110         return 0;
00111       }
00112 
00113       buf->p = q;
00114       buf->ptr = q;
00115       ip_addr_copy(buf->addr, *ip_current_src_addr());
00116       buf->port = pcb->protocol;
00117 
00118       len = q->tot_len;
00119       if (sys_mbox_trypost(&conn->recvmbox, buf) != ERR_OK) {
00120         netbuf_delete(buf);
00121         return 0;
00122       } else {
00123 #if LWIP_SO_RCVBUF
00124         SYS_ARCH_INC(conn->recv_avail, len);
00125 #endif /* LWIP_SO_RCVBUF */
00126         /* Register event with callback */
00127         API_EVENT(conn, NETCONN_EVT_RCVPLUS, len);
00128       }
00129     }
00130   }
00131 
00132   return 0; /* do not eat the packet */
00133 }
00134 #endif /* LWIP_RAW*/
00135 
00136 #if LWIP_UDP
00137 /**
00138  * Receive callback function for UDP netconns.
00139  * Posts the packet to conn->recvmbox or deletes it on memory error.
00140  *
00141  * @see udp.h (struct udp_pcb.recv) for parameters
00142  */
00143 static void
00144 recv_udp(void *arg, struct udp_pcb *pcb, struct pbuf *p,
00145    ip_addr_t *addr, u16_t port)
00146 {
00147   struct netbuf *buf;
00148   struct netconn *conn;
00149   u16_t len;
00150 #if LWIP_SO_RCVBUF
00151   int recv_avail;
00152 #endif /* LWIP_SO_RCVBUF */
00153 
00154   LWIP_UNUSED_ARG(pcb); /* only used for asserts... */
00155   LWIP_ASSERT("recv_udp must have a pcb argument", pcb != NULL);
00156   LWIP_ASSERT("recv_udp must have an argument", arg != NULL);
00157   conn = (struct netconn *)arg;
00158   LWIP_ASSERT("recv_udp: recv for wrong pcb!", conn->pcb.udp == pcb);
00159 
00160 #if LWIP_SO_RCVBUF
00161   SYS_ARCH_GET(conn->recv_avail, recv_avail);
00162   if ((conn == NULL) || !sys_mbox_valid(&conn->recvmbox) ||
00163       ((recv_avail + (int)(p->tot_len)) > conn->recv_bufsize)) {
00164 #else  /* LWIP_SO_RCVBUF */
00165   if ((conn == NULL) || !sys_mbox_valid(&conn->recvmbox)) {
00166 #endif /* LWIP_SO_RCVBUF */
00167     pbuf_free(p);
00168     return;
00169   }
00170 
00171   buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
00172   if (buf == NULL) {
00173     pbuf_free(p);
00174     return;
00175   } else {
00176     buf->p = p;
00177     buf->ptr = p;
00178     ip_addr_set(&buf->addr, addr);
00179     buf->port = port;
00180 #if LWIP_NETBUF_RECVINFO
00181     {
00182       const struct ip_hdr* iphdr = ip_current_header();
00183       /* get the UDP header - always in the first pbuf, ensured by udp_input */
00184       const struct udp_hdr* udphdr = (void*)(((char*)iphdr) + IPH_LEN(iphdr));
00185 #if LWIP_CHECKSUM_ON_COPY
00186       buf->flags = NETBUF_FLAG_DESTADDR;
00187 #endif /* LWIP_CHECKSUM_ON_COPY */
00188       ip_addr_set(&buf->toaddr, ip_current_dest_addr());
00189       buf->toport_chksum = udphdr->dest;
00190     }
00191 #endif /* LWIP_NETBUF_RECVINFO */
00192   }
00193 
00194   len = p->tot_len;
00195   if (sys_mbox_trypost(&conn->recvmbox, buf) != ERR_OK) {
00196     netbuf_delete(buf);
00197     return;
00198   } else {
00199 #if LWIP_SO_RCVBUF
00200     SYS_ARCH_INC(conn->recv_avail, len);
00201 #endif /* LWIP_SO_RCVBUF */
00202     /* Register event with callback */
00203     API_EVENT(conn, NETCONN_EVT_RCVPLUS, len);
00204   }
00205 }
00206 #endif /* LWIP_UDP */
00207 
00208 #if LWIP_TCP
00209 /**
00210  * Receive callback function for TCP netconns.
00211  * Posts the packet to conn->recvmbox, but doesn't delete it on errors.
00212  *
00213  * @see tcp.h (struct tcp_pcb.recv) for parameters and return value
00214  */
00215 static err_t
00216 recv_tcp(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
00217 {
00218   struct netconn *conn;
00219   u16_t len;
00220 
00221   LWIP_UNUSED_ARG(pcb);
00222   LWIP_ASSERT("recv_tcp must have a pcb argument", pcb != NULL);
00223   LWIP_ASSERT("recv_tcp must have an argument", arg != NULL);
00224   conn = (struct netconn *)arg;
00225   LWIP_ASSERT("recv_tcp: recv for wrong pcb!", conn->pcb.tcp == pcb);
00226 
00227   if (conn == NULL) {
00228     return ERR_VAL;
00229   }
00230   if (!sys_mbox_valid(&conn->recvmbox)) {
00231     /* recvmbox already deleted */
00232     if (p != NULL) {
00233       tcp_recved(pcb, p->tot_len);
00234       pbuf_free(p);
00235     }
00236     return ERR_OK;
00237   }
00238   /* Unlike for UDP or RAW pcbs, don't check for available space
00239      using recv_avail since that could break the connection
00240      (data is already ACKed) */
00241 
00242   /* don't overwrite fatal errors! */
00243   NETCONN_SET_SAFE_ERR(conn, err);
00244 
00245   if (p != NULL) {
00246     len = p->tot_len;
00247   } else {
00248     len = 0;
00249   }
00250 
00251   if (sys_mbox_trypost(&conn->recvmbox, p) != ERR_OK) {
00252     /* don't deallocate p: it is presented to us later again from tcp_fasttmr! */
00253     return ERR_MEM;
00254   } else {
00255 #if LWIP_SO_RCVBUF
00256     SYS_ARCH_INC(conn->recv_avail, len);
00257 #endif /* LWIP_SO_RCVBUF */
00258     /* Register event with callback */
00259     API_EVENT(conn, NETCONN_EVT_RCVPLUS, len);
00260   }
00261 
00262   return ERR_OK;
00263 }
00264 
00265 /**
00266  * Poll callback function for TCP netconns.
00267  * Wakes up an application thread that waits for a connection to close
00268  * or data to be sent. The application thread then takes the
00269  * appropriate action to go on.
00270  *
00271  * Signals the conn->sem.
00272  * netconn_close waits for conn->sem if closing failed.
00273  *
00274  * @see tcp.h (struct tcp_pcb.poll) for parameters and return value
00275  */
00276 static err_t
00277 poll_tcp(void *arg, struct tcp_pcb *pcb)
00278 {
00279   struct netconn *conn = (struct netconn *)arg;
00280 
00281   LWIP_UNUSED_ARG(pcb);
00282   LWIP_ASSERT("conn != NULL", (conn != NULL));
00283 
00284   if (conn->state == NETCONN_WRITE) {
00285     do_writemore(conn);
00286   } else if (conn->state == NETCONN_CLOSE) {
00287     do_close_internal(conn);
00288   }
00289   /* @todo: implement connect timeout here? */
00290 
00291   /* Did a nonblocking write fail before? Then check available write-space. */
00292   if (conn->flags & NETCONN_FLAG_CHECK_WRITESPACE) {
00293     /* If the queued byte- or pbuf-count drops below the configured low-water limit,
00294        let select mark this pcb as writable again. */
00295     if ((conn->pcb.tcp != NULL) && (tcp_sndbuf(conn->pcb.tcp) > TCP_SNDLOWAT) &&
00296       (tcp_sndqueuelen(conn->pcb.tcp) < TCP_SNDQUEUELOWAT)) {
00297       conn->flags &= ~NETCONN_FLAG_CHECK_WRITESPACE;
00298       API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
00299     }
00300   }
00301 
00302   return ERR_OK;
00303 }
00304 
00305 /**
00306  * Sent callback function for TCP netconns.
00307  * Signals the conn->sem and calls API_EVENT.
00308  * netconn_write waits for conn->sem if send buffer is low.
00309  *
00310  * @see tcp.h (struct tcp_pcb.sent) for parameters and return value
00311  */
00312 static err_t
00313 sent_tcp(void *arg, struct tcp_pcb *pcb, u16_t len)
00314 {
00315   struct netconn *conn = (struct netconn *)arg;
00316 
00317   LWIP_UNUSED_ARG(pcb);
00318   LWIP_ASSERT("conn != NULL", (conn != NULL));
00319 
00320   if (conn->state == NETCONN_WRITE) {
00321     do_writemore(conn);
00322   } else if (conn->state == NETCONN_CLOSE) {
00323     do_close_internal(conn);
00324   }
00325 
00326   if (conn) {
00327     /* If the queued byte- or pbuf-count drops below the configured low-water limit,
00328        let select mark this pcb as writable again. */
00329     if ((conn->pcb.tcp != NULL) && (tcp_sndbuf(conn->pcb.tcp) > TCP_SNDLOWAT) &&
00330       (tcp_sndqueuelen(conn->pcb.tcp) < TCP_SNDQUEUELOWAT)) {
00331       conn->flags &= ~NETCONN_FLAG_CHECK_WRITESPACE;
00332       API_EVENT(conn, NETCONN_EVT_SENDPLUS, len);
00333     }
00334   }
00335   
00336   return ERR_OK;
00337 }
00338 
00339 /**
00340  * Error callback function for TCP netconns.
00341  * Signals conn->sem, posts to all conn mboxes and calls API_EVENT.
00342  * The application thread has then to decide what to do.
00343  *
00344  * @see tcp.h (struct tcp_pcb.err) for parameters
00345  */
00346 static void
00347 err_tcp(void *arg, err_t err)
00348 {
00349   struct netconn *conn;
00350   enum netconn_state old_state;
00351   SYS_ARCH_DECL_PROTECT(lev);
00352 
00353   conn = (struct netconn *)arg;
00354   LWIP_ASSERT("conn != NULL", (conn != NULL));
00355 
00356   conn->pcb.tcp = NULL;
00357 
00358   /* no check since this is always fatal! */
00359   SYS_ARCH_PROTECT(lev);
00360   conn->last_err = err;
00361   SYS_ARCH_UNPROTECT(lev);
00362 
00363   /* reset conn->state now before waking up other threads */
00364   old_state = conn->state;
00365   conn->state = NETCONN_NONE;
00366 
00367   /* Notify the user layer about a connection error. Used to signal
00368      select. */
00369   API_EVENT(conn, NETCONN_EVT_ERROR, 0);
00370   /* Try to release selects pending on 'read' or 'write', too.
00371      They will get an error if they actually try to read or write. */
00372   API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
00373   API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
00374 
00375   /* pass NULL-message to recvmbox to wake up pending recv */
00376   if (sys_mbox_valid(&conn->recvmbox)) {
00377     /* use trypost to prevent deadlock */
00378     sys_mbox_trypost(&conn->recvmbox, NULL);
00379   }
00380   /* pass NULL-message to acceptmbox to wake up pending accept */
00381   if (sys_mbox_valid(&conn->acceptmbox)) {
00382     /* use trypost to preven deadlock */
00383     sys_mbox_trypost(&conn->acceptmbox, NULL);
00384   }
00385 
00386   if ((old_state == NETCONN_WRITE) || (old_state == NETCONN_CLOSE) ||
00387       (old_state == NETCONN_CONNECT)) {
00388     /* calling do_writemore/do_close_internal is not necessary
00389        since the pcb has already been deleted! */
00390     int was_nonblocking_connect = IN_NONBLOCKING_CONNECT(conn);
00391     SET_NONBLOCKING_CONNECT(conn, 0);
00392 
00393     if (!was_nonblocking_connect) {
00394       /* set error return code */
00395       LWIP_ASSERT("conn->current_msg != NULL", conn->current_msg != NULL);
00396       conn->current_msg->err = err;
00397       conn->current_msg = NULL;
00398       /* wake up the waiting task */
00399       sys_sem_signal(&conn->op_completed);
00400     }
00401   } else {
00402     LWIP_ASSERT("conn->current_msg == NULL", conn->current_msg == NULL);
00403   }
00404 }
00405 
00406 /**
00407  * Setup a tcp_pcb with the correct callback function pointers
00408  * and their arguments.
00409  *
00410  * @param conn the TCP netconn to setup
00411  */
00412 static void
00413 setup_tcp(struct netconn *conn)
00414 {
00415   struct tcp_pcb *pcb;
00416 
00417   pcb = conn->pcb.tcp;
00418   tcp_arg(pcb, conn);
00419   tcp_recv(pcb, recv_tcp);
00420   tcp_sent(pcb, sent_tcp);
00421   tcp_poll(pcb, poll_tcp, 4);
00422   tcp_err(pcb, err_tcp);
00423 }
00424 
00425 /**
00426  * Accept callback function for TCP netconns.
00427  * Allocates a new netconn and posts that to conn->acceptmbox.
00428  *
00429  * @see tcp.h (struct tcp_pcb_listen.accept) for parameters and return value
00430  */
00431 static err_t
00432 accept_function(void *arg, struct tcp_pcb *newpcb, err_t err)
00433 {
00434   struct netconn *newconn;
00435   struct netconn *conn = (struct netconn *)arg;
00436 
00437   LWIP_DEBUGF(API_MSG_DEBUG, ("accept_function: newpcb->tate: %s\n", tcp_debug_state_str(newpcb->state)));
00438 
00439   if (!sys_mbox_valid(&conn->acceptmbox)) {
00440     LWIP_DEBUGF(API_MSG_DEBUG, ("accept_function: acceptmbox already deleted\n"));
00441     return ERR_VAL;
00442   }
00443 
00444   /* We have to set the callback here even though
00445    * the new socket is unknown. conn->socket is marked as -1. */
00446   newconn = netconn_alloc(conn->type, conn->callback);
00447   if (newconn == NULL) {
00448     return ERR_MEM;
00449   }
00450   newconn->pcb.tcp = newpcb;
00451   setup_tcp(newconn);
00452   /* no protection: when creating the pcb, the netconn is not yet known
00453      to the application thread */
00454   newconn->last_err = err;
00455 
00456   if (sys_mbox_trypost(&conn->acceptmbox, newconn) != ERR_OK) {
00457     /* When returning != ERR_OK, the pcb is aborted in tcp_process(),
00458        so do nothing here! */
00459     newconn->pcb.tcp = NULL;
00460     /* no need to drain since we know the recvmbox is empty. */
00461     sys_mbox_free(&newconn->recvmbox);
00462     sys_mbox_set_invalid(&newconn->recvmbox);
00463     netconn_free(newconn);
00464     return ERR_MEM;
00465   } else {
00466     /* Register event with callback */
00467     API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
00468   }
00469 
00470   return ERR_OK;
00471 }
00472 #endif /* LWIP_TCP */
00473 
00474 /**
00475  * Create a new pcb of a specific type.
00476  * Called from do_newconn().
00477  *
00478  * @param msg the api_msg_msg describing the connection type
00479  * @return msg->conn->err, but the return value is currently ignored
00480  */
00481 static void
00482 pcb_new(struct api_msg_msg *msg)
00483 {
00484   LWIP_ASSERT("pcb_new: pcb already allocated", msg->conn->pcb.tcp == NULL);
00485 
00486   /* Allocate a PCB for this connection */
00487   switch(NETCONNTYPE_GROUP(msg->conn->type)) {
00488 #if LWIP_RAW
00489   case NETCONN_RAW:
00490     msg->conn->pcb.raw = raw_new(msg->msg.n.proto);
00491     if(msg->conn->pcb.raw == NULL) {
00492       msg->err = ERR_MEM;
00493       break;
00494     }
00495     raw_recv(msg->conn->pcb.raw, recv_raw, msg->conn);
00496     break;
00497 #endif /* LWIP_RAW */
00498 #if LWIP_UDP
00499   case NETCONN_UDP:
00500     msg->conn->pcb.udp = udp_new();
00501     if(msg->conn->pcb.udp == NULL) {
00502       msg->err = ERR_MEM;
00503       break;
00504     }
00505 #if LWIP_UDPLITE
00506     if (msg->conn->type==NETCONN_UDPLITE) {
00507       udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_UDPLITE);
00508     }
00509 #endif /* LWIP_UDPLITE */
00510     if (msg->conn->type==NETCONN_UDPNOCHKSUM) {
00511       udp_setflags(msg->conn->pcb.udp, UDP_FLAGS_NOCHKSUM);
00512     }
00513     udp_recv(msg->conn->pcb.udp, recv_udp, msg->conn);
00514     break;
00515 #endif /* LWIP_UDP */
00516 #if LWIP_TCP
00517   case NETCONN_TCP:
00518     msg->conn->pcb.tcp = tcp_new();
00519     if(msg->conn->pcb.tcp == NULL) {
00520       msg->err = ERR_MEM;
00521       break;
00522     }
00523     setup_tcp(msg->conn);
00524     break;
00525 #endif /* LWIP_TCP */
00526   default:
00527     /* Unsupported netconn type, e.g. protocol disabled */
00528     msg->err = ERR_VAL;
00529     break;
00530   }
00531 }
00532 
00533 /**
00534  * Create a new pcb of a specific type inside a netconn.
00535  * Called from netconn_new_with_proto_and_callback.
00536  *
00537  * @param msg the api_msg_msg describing the connection type
00538  */
00539 void
00540 do_newconn(struct api_msg_msg *msg)
00541 {
00542   msg->err = ERR_OK;
00543   if(msg->conn->pcb.tcp == NULL) {
00544     pcb_new(msg);
00545   }
00546   /* Else? This "new" connection already has a PCB allocated. */
00547   /* Is this an error condition? Should it be deleted? */
00548   /* We currently just are happy and return. */
00549 
00550   TCPIP_APIMSG_ACK(msg);
00551 }
00552 
00553 /**
00554  * Create a new netconn (of a specific type) that has a callback function.
00555  * The corresponding pcb is NOT created!
00556  *
00557  * @param t the type of 'connection' to create (@see enum netconn_type)
00558  * @param proto the IP protocol for RAW IP pcbs
00559  * @param callback a function to call on status changes (RX available, TX'ed)
00560  * @return a newly allocated struct netconn or
00561  *         NULL on memory error
00562  */
00563 struct netconn*
00564 netconn_alloc(enum netconn_type t, netconn_callback callback)
00565 {
00566   struct netconn *conn;
00567   int size;
00568 
00569   conn = (struct netconn *)memp_malloc(MEMP_NETCONN);
00570   if (conn == NULL) {
00571     return NULL;
00572   }
00573 
00574   conn->last_err = ERR_OK;
00575   conn->type = t;
00576   conn->pcb.tcp = NULL;
00577 
00578 #if (DEFAULT_RAW_RECVMBOX_SIZE == DEFAULT_UDP_RECVMBOX_SIZE) && \
00579     (DEFAULT_RAW_RECVMBOX_SIZE == DEFAULT_TCP_RECVMBOX_SIZE)
00580   size = DEFAULT_RAW_RECVMBOX_SIZE;
00581 #else
00582   switch(NETCONNTYPE_GROUP(t)) {
00583 #if LWIP_RAW
00584   case NETCONN_RAW:
00585     size = DEFAULT_RAW_RECVMBOX_SIZE;
00586     break;
00587 #endif /* LWIP_RAW */
00588 #if LWIP_UDP
00589   case NETCONN_UDP:
00590     size = DEFAULT_UDP_RECVMBOX_SIZE;
00591     break;
00592 #endif /* LWIP_UDP */
00593 #if LWIP_TCP
00594   case NETCONN_TCP:
00595     size = DEFAULT_TCP_RECVMBOX_SIZE;
00596     break;
00597 #endif /* LWIP_TCP */
00598   default:
00599     LWIP_ASSERT("netconn_alloc: undefined netconn_type", 0);
00600     break;
00601   }
00602 #endif
00603 
00604   if (sys_sem_new(&conn->op_completed, 0) != ERR_OK) {
00605     memp_free(MEMP_NETCONN, conn);
00606     return NULL;
00607   }
00608   if (sys_mbox_new(&conn->recvmbox, size) != ERR_OK) {
00609     sys_sem_free(&conn->op_completed);
00610     memp_free(MEMP_NETCONN, conn);
00611     return NULL;
00612   }
00613 
00614 #if LWIP_TCP
00615   sys_mbox_set_invalid(&conn->acceptmbox);
00616 #endif
00617   conn->state        = NETCONN_NONE;
00618 #if LWIP_SOCKET
00619   /* initialize socket to -1 since 0 is a valid socket */
00620   conn->socket       = -1;
00621 #endif /* LWIP_SOCKET */
00622   conn->callback     = callback;
00623 #if LWIP_TCP
00624   conn->current_msg  = NULL;
00625   conn->write_offset = 0;
00626 #endif /* LWIP_TCP */
00627 #if LWIP_SO_RCVTIMEO
00628   conn->recv_timeout = 0;
00629 #endif /* LWIP_SO_RCVTIMEO */
00630 #if LWIP_SO_RCVBUF
00631   conn->recv_bufsize = RECV_BUFSIZE_DEFAULT;
00632   conn->recv_avail   = 0;
00633 #endif /* LWIP_SO_RCVBUF */
00634   conn->flags = 0;
00635   return conn;
00636 }
00637 
00638 /**
00639  * Delete a netconn and all its resources.
00640  * The pcb is NOT freed (since we might not be in the right thread context do this).
00641  *
00642  * @param conn the netconn to free
00643  */
00644 void
00645 netconn_free(struct netconn *conn)
00646 {
00647   LWIP_ASSERT("PCB must be deallocated outside this function", conn->pcb.tcp == NULL);
00648   LWIP_ASSERT("recvmbox must be deallocated before calling this function",
00649     !sys_mbox_valid(&conn->recvmbox));
00650 #if LWIP_TCP
00651   LWIP_ASSERT("acceptmbox must be deallocated before calling this function",
00652     !sys_mbox_valid(&conn->acceptmbox));
00653 #endif /* LWIP_TCP */
00654 
00655   sys_sem_free(&conn->op_completed);
00656   sys_sem_set_invalid(&conn->op_completed);
00657 
00658   memp_free(MEMP_NETCONN, conn);
00659 }
00660 
00661 /**
00662  * Delete rcvmbox and acceptmbox of a netconn and free the left-over data in
00663  * these mboxes
00664  *
00665  * @param conn the netconn to free
00666  * @bytes_drained bytes drained from recvmbox
00667  * @accepts_drained pending connections drained from acceptmbox
00668  */
00669 static void
00670 netconn_drain(struct netconn *conn)
00671 {
00672   void *mem;
00673 #if LWIP_TCP
00674   struct pbuf *p;
00675 #endif /* LWIP_TCP */
00676 
00677   /* This runs in tcpip_thread, so we don't need to lock against rx packets */
00678 
00679   /* Delete and drain the recvmbox. */
00680   if (sys_mbox_valid(&conn->recvmbox)) {
00681     while (sys_mbox_tryfetch(&conn->recvmbox, &mem) != SYS_MBOX_EMPTY) {
00682 #if LWIP_TCP
00683       if (conn->type == NETCONN_TCP) {
00684         if(mem != NULL) {
00685           p = (struct pbuf*)mem;
00686           /* pcb might be set to NULL already by err_tcp() */
00687           if (conn->pcb.tcp != NULL) {
00688             tcp_recved(conn->pcb.tcp, p->tot_len);
00689           }
00690           pbuf_free(p);
00691         }
00692       } else
00693 #endif /* LWIP_TCP */
00694       {
00695         netbuf_delete((struct netbuf *)mem);
00696       }
00697     }
00698     sys_mbox_free(&conn->recvmbox);
00699     sys_mbox_set_invalid(&conn->recvmbox);
00700   }
00701 
00702   /* Delete and drain the acceptmbox. */
00703 #if LWIP_TCP
00704   if (sys_mbox_valid(&conn->acceptmbox)) {
00705     while (sys_mbox_tryfetch(&conn->acceptmbox, &mem) != SYS_MBOX_EMPTY) {
00706       struct netconn *newconn = (struct netconn *)mem;
00707       /* Only tcp pcbs have an acceptmbox, so no need to check conn->type */
00708       /* pcb might be set to NULL already by err_tcp() */
00709       if (conn->pcb.tcp != NULL) {
00710         tcp_accepted(conn->pcb.tcp);
00711       }
00712       /* drain recvmbox */
00713       netconn_drain(newconn);
00714       if (newconn->pcb.tcp != NULL) {
00715         tcp_abort(newconn->pcb.tcp);
00716         newconn->pcb.tcp = NULL;
00717       }
00718       netconn_free(newconn);
00719     }
00720     sys_mbox_free(&conn->acceptmbox);
00721     sys_mbox_set_invalid(&conn->acceptmbox);
00722   }
00723 #endif /* LWIP_TCP */
00724 }
00725 
00726 #if LWIP_TCP
00727 /**
00728  * Internal helper function to close a TCP netconn: since this sometimes
00729  * doesn't work at the first attempt, this function is called from multiple
00730  * places.
00731  *
00732  * @param conn the TCP netconn to close
00733  */
00734 static void
00735 do_close_internal(struct netconn *conn)
00736 {
00737   err_t err;
00738   u8_t shut, shut_rx, shut_tx, close;
00739 
00740   LWIP_ASSERT("invalid conn", (conn != NULL));
00741   LWIP_ASSERT("this is for tcp netconns only", (conn->type == NETCONN_TCP));
00742   LWIP_ASSERT("conn must be in state NETCONN_CLOSE", (conn->state == NETCONN_CLOSE));
00743   LWIP_ASSERT("pcb already closed", (conn->pcb.tcp != NULL));
00744   LWIP_ASSERT("conn->current_msg != NULL", conn->current_msg != NULL);
00745 
00746   shut = conn->current_msg->msg.sd.shut;
00747   shut_rx = shut & NETCONN_SHUT_RD;
00748   shut_tx = shut & NETCONN_SHUT_WR;
00749   /* shutting down both ends is the same as closing */
00750   close = shut == NETCONN_SHUT_RDWR;
00751 
00752   /* Set back some callback pointers */
00753   if (close) {
00754     tcp_arg(conn->pcb.tcp, NULL);
00755   }
00756   if (conn->pcb.tcp->state == LISTEN) {
00757     tcp_accept(conn->pcb.tcp, NULL);
00758   } else {
00759     /* some callbacks have to be reset if tcp_close is not successful */
00760     if (shut_rx) {
00761       tcp_recv(conn->pcb.tcp, NULL);
00762       tcp_accept(conn->pcb.tcp, NULL);
00763     }
00764     if (shut_tx) {
00765       tcp_sent(conn->pcb.tcp, NULL);
00766     }
00767     if (close) {
00768       tcp_poll(conn->pcb.tcp, NULL, 4);
00769       tcp_err(conn->pcb.tcp, NULL);
00770     }
00771   }
00772   /* Try to close the connection */
00773   if (shut == NETCONN_SHUT_RDWR) {
00774     err = tcp_close(conn->pcb.tcp);
00775   } else {
00776     err = tcp_shutdown(conn->pcb.tcp, shut & NETCONN_SHUT_RD, shut & NETCONN_SHUT_WR);
00777   }
00778   if (err == ERR_OK) {
00779     /* Closing succeeded */
00780     conn->current_msg->err = ERR_OK;
00781     conn->current_msg = NULL;
00782     conn->state = NETCONN_NONE;
00783     /* Set back some callback pointers as conn is going away */
00784     conn->pcb.tcp = NULL;
00785     /* Trigger select() in socket layer. Make sure everybody notices activity
00786        on the connection, error first! */
00787     if (close) {
00788       API_EVENT(conn, NETCONN_EVT_ERROR, 0);
00789     }
00790     if (shut_rx) {
00791       API_EVENT(conn, NETCONN_EVT_RCVPLUS, 0);
00792     }
00793     if (shut_tx) {
00794       API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
00795     }
00796     /* wake up the application task */
00797     sys_sem_signal(&conn->op_completed);
00798   } else {
00799     /* Closing failed, restore some of the callbacks */
00800     /* Closing of listen pcb will never fail! */
00801     LWIP_ASSERT("Closing a listen pcb may not fail!", (conn->pcb.tcp->state != LISTEN));
00802     tcp_sent(conn->pcb.tcp, sent_tcp);
00803     tcp_poll(conn->pcb.tcp, poll_tcp, 4);
00804     tcp_err(conn->pcb.tcp, err_tcp);
00805     tcp_arg(conn->pcb.tcp, conn);
00806     /* don't restore recv callback: we don't want to receive any more data */
00807   }
00808   /* If closing didn't succeed, we get called again either
00809      from poll_tcp or from sent_tcp */
00810 }
00811 #endif /* LWIP_TCP */
00812 
00813 /**
00814  * Delete the pcb inside a netconn.
00815  * Called from netconn_delete.
00816  *
00817  * @param msg the api_msg_msg pointing to the connection
00818  */
00819 void
00820 do_delconn(struct api_msg_msg *msg)
00821 {
00822   /* @todo TCP: abort running write/connect? */
00823  if ((msg->conn->state != NETCONN_NONE) &&
00824      (msg->conn->state != NETCONN_LISTEN) &&
00825      (msg->conn->state != NETCONN_CONNECT)) {
00826     /* this only happens for TCP netconns */
00827     LWIP_ASSERT("msg->conn->type == NETCONN_TCP", msg->conn->type == NETCONN_TCP);
00828     msg->err = ERR_INPROGRESS;
00829   } else {
00830     LWIP_ASSERT("blocking connect in progress",
00831       (msg->conn->state != NETCONN_CONNECT) || IN_NONBLOCKING_CONNECT(msg->conn));
00832     /* Drain and delete mboxes */
00833     netconn_drain(msg->conn);
00834 
00835     if (msg->conn->pcb.tcp != NULL) {
00836 
00837       switch (NETCONNTYPE_GROUP(msg->conn->type)) {
00838 #if LWIP_RAW
00839       case NETCONN_RAW:
00840         raw_remove(msg->conn->pcb.raw);
00841         break;
00842 #endif /* LWIP_RAW */
00843 #if LWIP_UDP
00844       case NETCONN_UDP:
00845         msg->conn->pcb.udp->recv_arg = NULL;
00846         udp_remove(msg->conn->pcb.udp);
00847         break;
00848 #endif /* LWIP_UDP */
00849 #if LWIP_TCP
00850       case NETCONN_TCP:
00851         LWIP_ASSERT("already writing or closing", msg->conn->current_msg == NULL &&
00852           msg->conn->write_offset == 0);
00853         msg->conn->state = NETCONN_CLOSE;
00854         msg->msg.sd.shut = NETCONN_SHUT_RDWR;
00855         msg->conn->current_msg = msg;
00856         do_close_internal(msg->conn);
00857         /* API_EVENT is called inside do_close_internal, before releasing
00858            the application thread, so we can return at this point! */
00859         return;
00860 #endif /* LWIP_TCP */
00861       default:
00862         break;
00863       }
00864       msg->conn->pcb.tcp = NULL;
00865     }
00866     /* tcp netconns don't come here! */
00867 
00868     /* @todo: this lets select make the socket readable and writable,
00869        which is wrong! errfd instead? */
00870     API_EVENT(msg->conn, NETCONN_EVT_RCVPLUS, 0);
00871     API_EVENT(msg->conn, NETCONN_EVT_SENDPLUS, 0);
00872   }
00873   if (sys_sem_valid(&msg->conn->op_completed)) {
00874     sys_sem_signal(&msg->conn->op_completed);
00875   }
00876 }
00877 
00878 /**
00879  * Bind a pcb contained in a netconn
00880  * Called from netconn_bind.
00881  *
00882  * @param msg the api_msg_msg pointing to the connection and containing
00883  *            the IP address and port to bind to
00884  */
00885 void
00886 do_bind(struct api_msg_msg *msg)
00887 {
00888   if (ERR_IS_FATAL(msg->conn->last_err)) {
00889     msg->err = msg->conn->last_err;
00890   } else {
00891     msg->err = ERR_VAL;
00892     if (msg->conn->pcb.tcp != NULL) {
00893       switch (NETCONNTYPE_GROUP(msg->conn->type)) {
00894 #if LWIP_RAW
00895       case NETCONN_RAW:
00896         msg->err = raw_bind(msg->conn->pcb.raw, msg->msg.bc.ipaddr);
00897         break;
00898 #endif /* LWIP_RAW */
00899 #if LWIP_UDP
00900       case NETCONN_UDP:
00901         msg->err = udp_bind(msg->conn->pcb.udp, msg->msg.bc.ipaddr, msg->msg.bc.port);
00902         break;
00903 #endif /* LWIP_UDP */
00904 #if LWIP_TCP
00905       case NETCONN_TCP:
00906         msg->err = tcp_bind(msg->conn->pcb.tcp, msg->msg.bc.ipaddr, msg->msg.bc.port);
00907         break;
00908 #endif /* LWIP_TCP */
00909       default:
00910         break;
00911       }
00912     }
00913   }
00914   TCPIP_APIMSG_ACK(msg);
00915 }
00916 
00917 #if LWIP_TCP
00918 /**
00919  * TCP callback function if a connection (opened by tcp_connect/do_connect) has
00920  * been established (or reset by the remote host).
00921  *
00922  * @see tcp.h (struct tcp_pcb.connected) for parameters and return values
00923  */
00924 static err_t
00925 do_connected(void *arg, struct tcp_pcb *pcb, err_t err)
00926 {
00927   struct netconn *conn;
00928   int was_blocking;
00929 
00930   LWIP_UNUSED_ARG(pcb);
00931 
00932   conn = (struct netconn *)arg;
00933 
00934   if (conn == NULL) {
00935     return ERR_VAL;
00936   }
00937 
00938   LWIP_ASSERT("conn->state == NETCONN_CONNECT", conn->state == NETCONN_CONNECT);
00939   LWIP_ASSERT("(conn->current_msg != NULL) || conn->in_non_blocking_connect",
00940     (conn->current_msg != NULL) || IN_NONBLOCKING_CONNECT(conn));
00941 
00942   if (conn->current_msg != NULL) {
00943     conn->current_msg->err = err;
00944   }
00945   if ((conn->type == NETCONN_TCP) && (err == ERR_OK)) {
00946     setup_tcp(conn);
00947   }
00948   was_blocking = !IN_NONBLOCKING_CONNECT(conn);
00949   SET_NONBLOCKING_CONNECT(conn, 0);
00950   conn->current_msg = NULL;
00951   conn->state = NETCONN_NONE;
00952   if (!was_blocking) {
00953     NETCONN_SET_SAFE_ERR(conn, ERR_OK);
00954   }
00955   API_EVENT(conn, NETCONN_EVT_SENDPLUS, 0);
00956 
00957   if (was_blocking) {
00958     sys_sem_signal(&conn->op_completed);
00959   }
00960   return ERR_OK;
00961 }
00962 #endif /* LWIP_TCP */
00963 
00964 /**
00965  * Connect a pcb contained inside a netconn
00966  * Called from netconn_connect.
00967  *
00968  * @param msg the api_msg_msg pointing to the connection and containing
00969  *            the IP address and port to connect to
00970  */
00971 void
00972 do_connect(struct api_msg_msg *msg)
00973 {
00974   if (msg->conn->pcb.tcp == NULL) {
00975     /* This may happen when calling netconn_connect() a second time */
00976     msg->err = ERR_CLSD;
00977   } else {
00978     switch (NETCONNTYPE_GROUP(msg->conn->type)) {
00979 #if LWIP_RAW
00980   case NETCONN_RAW:
00981     msg->err = raw_connect(msg->conn->pcb.raw, msg->msg.bc.ipaddr);
00982     break;
00983 #endif /* LWIP_RAW */
00984 #if LWIP_UDP
00985   case NETCONN_UDP:
00986     msg->err = udp_connect(msg->conn->pcb.udp, msg->msg.bc.ipaddr, msg->msg.bc.port);
00987     break;
00988 #endif /* LWIP_UDP */
00989 #if LWIP_TCP
00990   case NETCONN_TCP:
00991     /* Prevent connect while doing any other action. */
00992     if (msg->conn->state != NETCONN_NONE) {
00993       msg->err = ERR_ISCONN;
00994     } else {
00995       setup_tcp(msg->conn);
00996       msg->err = tcp_connect(msg->conn->pcb.tcp, msg->msg.bc.ipaddr,
00997         msg->msg.bc.port, do_connected);
00998       if (msg->err == ERR_OK) {
00999         u8_t non_blocking = netconn_is_nonblocking(msg->conn);
01000         msg->conn->state = NETCONN_CONNECT;
01001         SET_NONBLOCKING_CONNECT(msg->conn, non_blocking);
01002         if (non_blocking) {
01003           msg->err = ERR_INPROGRESS;
01004         } else {
01005           msg->conn->current_msg = msg;
01006           /* sys_sem_signal() is called from do_connected (or err_tcp()),
01007           * when the connection is established! */
01008           return;
01009         }
01010       }
01011     }
01012     break;
01013 #endif /* LWIP_TCP */
01014   default:
01015     LWIP_ERROR("Invalid netconn type", 0, do{ msg->err = ERR_VAL; }while(0));
01016     break;
01017     }
01018   }
01019   sys_sem_signal(&msg->conn->op_completed);
01020 }
01021 
01022 /**
01023  * Connect a pcb contained inside a netconn
01024  * Only used for UDP netconns.
01025  * Called from netconn_disconnect.
01026  *
01027  * @param msg the api_msg_msg pointing to the connection to disconnect
01028  */
01029 void
01030 do_disconnect(struct api_msg_msg *msg)
01031 {
01032 #if LWIP_UDP
01033   if (NETCONNTYPE_GROUP(msg->conn->type) == NETCONN_UDP) {
01034     udp_disconnect(msg->conn->pcb.udp);
01035     msg->err = ERR_OK;
01036   } else
01037 #endif /* LWIP_UDP */
01038   {
01039     msg->err = ERR_VAL;
01040   }
01041   TCPIP_APIMSG_ACK(msg);
01042 }
01043 
01044 #if LWIP_TCP
01045 /**
01046  * Set a TCP pcb contained in a netconn into listen mode
01047  * Called from netconn_listen.
01048  *
01049  * @param msg the api_msg_msg pointing to the connection
01050  */
01051 void
01052 do_listen(struct api_msg_msg *msg)
01053 {
01054   if (ERR_IS_FATAL(msg->conn->last_err)) {
01055     msg->err = msg->conn->last_err;
01056   } else {
01057     msg->err = ERR_CONN;
01058     if (msg->conn->pcb.tcp != NULL) {
01059       if (msg->conn->type == NETCONN_TCP) {
01060         if (msg->conn->state == NETCONN_NONE) {
01061 #if TCP_LISTEN_BACKLOG
01062           struct tcp_pcb* lpcb = tcp_listen_with_backlog(msg->conn->pcb.tcp, msg->msg.lb.backlog);
01063 #else  /* TCP_LISTEN_BACKLOG */
01064           struct tcp_pcb* lpcb = tcp_listen(msg->conn->pcb.tcp);
01065 #endif /* TCP_LISTEN_BACKLOG */
01066           if (lpcb == NULL) {
01067             /* in this case, the old pcb is still allocated */
01068             msg->err = ERR_MEM;
01069           } else {
01070             /* delete the recvmbox and allocate the acceptmbox */
01071             if (sys_mbox_valid(&msg->conn->recvmbox)) {
01072               /** @todo: should we drain the recvmbox here? */
01073               sys_mbox_free(&msg->conn->recvmbox);
01074               sys_mbox_set_invalid(&msg->conn->recvmbox);
01075             }
01076             msg->err = ERR_OK;
01077             if (!sys_mbox_valid(&msg->conn->acceptmbox)) {
01078               msg->err = sys_mbox_new(&msg->conn->acceptmbox, DEFAULT_ACCEPTMBOX_SIZE);
01079             }
01080             if (msg->err == ERR_OK) {
01081               msg->conn->state = NETCONN_LISTEN;
01082               msg->conn->pcb.tcp = lpcb;
01083               tcp_arg(msg->conn->pcb.tcp, msg->conn);
01084               tcp_accept(msg->conn->pcb.tcp, accept_function);
01085             } else {
01086               /* since the old pcb is already deallocated, free lpcb now */
01087               tcp_close(lpcb);
01088               msg->conn->pcb.tcp = NULL;
01089             }
01090           }
01091         }
01092       }
01093     }
01094   }
01095   TCPIP_APIMSG_ACK(msg);
01096 }
01097 #endif /* LWIP_TCP */
01098 
01099 /**
01100  * Send some data on a RAW or UDP pcb contained in a netconn
01101  * Called from netconn_send
01102  *
01103  * @param msg the api_msg_msg pointing to the connection
01104  */
01105 void
01106 do_send(struct api_msg_msg *msg)
01107 {
01108   if (ERR_IS_FATAL(msg->conn->last_err)) {
01109     msg->err = msg->conn->last_err;
01110   } else {
01111     msg->err = ERR_CONN;
01112     if (msg->conn->pcb.tcp != NULL) {
01113       switch (NETCONNTYPE_GROUP(msg->conn->type)) {
01114 #if LWIP_RAW
01115       case NETCONN_RAW:
01116         if (ip_addr_isany(&msg->msg.b->addr)) {
01117           msg->err = raw_send(msg->conn->pcb.raw, msg->msg.b->p);
01118         } else {
01119           msg->err = raw_sendto(msg->conn->pcb.raw, msg->msg.b->p, &msg->msg.b->addr);
01120         }
01121         break;
01122 #endif
01123 #if LWIP_UDP
01124       case NETCONN_UDP:
01125 #if LWIP_CHECKSUM_ON_COPY
01126         if (ip_addr_isany(&msg->msg.b->addr)) {
01127           msg->err = udp_send_chksum(msg->conn->pcb.udp, msg->msg.b->p,
01128             msg->msg.b->flags & NETBUF_FLAG_CHKSUM, msg->msg.b->toport_chksum);
01129         } else {
01130           msg->err = udp_sendto_chksum(msg->conn->pcb.udp, msg->msg.b->p,
01131             &msg->msg.b->addr, msg->msg.b->port,
01132             msg->msg.b->flags & NETBUF_FLAG_CHKSUM, msg->msg.b->toport_chksum);
01133         }
01134 #else /* LWIP_CHECKSUM_ON_COPY */
01135         if (ip_addr_isany(&msg->msg.b->addr)) {
01136           msg->err = udp_send(msg->conn->pcb.udp, msg->msg.b->p);
01137         } else {
01138           msg->err = udp_sendto(msg->conn->pcb.udp, msg->msg.b->p, &msg->msg.b->addr, msg->msg.b->port);
01139         }
01140 #endif /* LWIP_CHECKSUM_ON_COPY */
01141         break;
01142 #endif /* LWIP_UDP */
01143       default:
01144         break;
01145       }
01146     }
01147   }
01148   TCPIP_APIMSG_ACK(msg);
01149 }
01150 
01151 #if LWIP_TCP
01152 /**
01153  * Indicate data has been received from a TCP pcb contained in a netconn
01154  * Called from netconn_recv
01155  *
01156  * @param msg the api_msg_msg pointing to the connection
01157  */
01158 void
01159 do_recv(struct api_msg_msg *msg)
01160 {
01161   msg->err = ERR_OK;
01162   if (msg->conn->pcb.tcp != NULL) {
01163     if (msg->conn->type == NETCONN_TCP) {
01164 #if TCP_LISTEN_BACKLOG
01165       if (msg->conn->pcb.tcp->state == LISTEN) {
01166         tcp_accepted(msg->conn->pcb.tcp);
01167       } else
01168 #endif /* TCP_LISTEN_BACKLOG */
01169       {
01170         u32_t remaining = msg->msg.r.len;
01171         do {
01172           u16_t recved = (remaining > 0xffff) ? 0xffff : (u16_t)remaining;
01173           tcp_recved(msg->conn->pcb.tcp, recved);
01174           remaining -= recved;
01175         }while(remaining != 0);
01176       }
01177     }
01178   }
01179   TCPIP_APIMSG_ACK(msg);
01180 }
01181 
01182 /**
01183  * See if more data needs to be written from a previous call to netconn_write.
01184  * Called initially from do_write. If the first call can't send all data
01185  * (because of low memory or empty send-buffer), this function is called again
01186  * from sent_tcp() or poll_tcp() to send more data. If all data is sent, the
01187  * blocking application thread (waiting in netconn_write) is released.
01188  *
01189  * @param conn netconn (that is currently in state NETCONN_WRITE) to process
01190  * @return ERR_OK
01191  *         ERR_MEM if LWIP_TCPIP_CORE_LOCKING=1 and sending hasn't yet finished
01192  */
01193 static err_t
01194 do_writemore(struct netconn *conn)
01195 {
01196   err_t err = ERR_OK;
01197   void *dataptr;
01198   u16_t len, available;
01199   u8_t write_finished = 0;
01200   size_t diff;
01201   u8_t dontblock = netconn_is_nonblocking(conn) ||
01202        (conn->current_msg->msg.w.apiflags & NETCONN_DONTBLOCK);
01203   u8_t apiflags = conn->current_msg->msg.w.apiflags;
01204 
01205   LWIP_ASSERT("conn != NULL", conn != NULL);
01206   LWIP_ASSERT("conn->state == NETCONN_WRITE", (conn->state == NETCONN_WRITE));
01207   LWIP_ASSERT("conn->current_msg != NULL", conn->current_msg != NULL);
01208   LWIP_ASSERT("conn->pcb.tcp != NULL", conn->pcb.tcp != NULL);
01209   LWIP_ASSERT("conn->write_offset < conn->current_msg->msg.w.len",
01210     conn->write_offset < conn->current_msg->msg.w.len);
01211 
01212   dataptr = (u8_t*)conn->current_msg->msg.w.dataptr + conn->write_offset;
01213   diff = conn->current_msg->msg.w.len - conn->write_offset;
01214   if (diff > 0xffffUL) { /* max_u16_t */
01215     len = 0xffff;
01216 #if LWIP_TCPIP_CORE_LOCKING
01217     conn->flags |= NETCONN_FLAG_WRITE_DELAYED;
01218 #endif
01219     apiflags |= TCP_WRITE_FLAG_MORE;
01220   } else {
01221     len = (u16_t)diff;
01222   }
01223   available = tcp_sndbuf(conn->pcb.tcp);
01224   if (available < len) {
01225     /* don't try to write more than sendbuf */
01226     len = available;
01227 #if LWIP_TCPIP_CORE_LOCKING
01228     conn->flags |= NETCONN_FLAG_WRITE_DELAYED;
01229 #endif
01230     apiflags |= TCP_WRITE_FLAG_MORE;
01231   }
01232   if (dontblock && (len < conn->current_msg->msg.w.len)) {
01233     /* failed to send all data at once -> nonblocking write not possible */
01234     err = ERR_MEM;
01235   }
01236   if (err == ERR_OK) {
01237     LWIP_ASSERT("do_writemore: invalid length!", ((conn->write_offset + len) <= conn->current_msg->msg.w.len));
01238     err = tcp_write(conn->pcb.tcp, dataptr, len, apiflags);
01239   }
01240   if (dontblock && (err == ERR_MEM)) {
01241     /* nonblocking write failed */
01242     write_finished = 1;
01243     err = ERR_WOULDBLOCK;
01244     /* let poll_tcp check writable space to mark the pcb
01245        writable again */
01246     conn->flags |= NETCONN_FLAG_CHECK_WRITESPACE;
01247     /* let select mark this pcb as non-writable. */
01248     API_EVENT(conn, NETCONN_EVT_SENDMINUS, len);
01249   } else {
01250     /* if OK or memory error, check available space */
01251     if (((err == ERR_OK) || (err == ERR_MEM)) &&
01252         ((tcp_sndbuf(conn->pcb.tcp) <= TCP_SNDLOWAT) ||
01253          (tcp_sndqueuelen(conn->pcb.tcp) >= TCP_SNDQUEUELOWAT))) {
01254       /* The queued byte- or pbuf-count exceeds the configured low-water limit,
01255          let select mark this pcb as non-writable. */
01256       API_EVENT(conn, NETCONN_EVT_SENDMINUS, len);
01257     }
01258 
01259     if (err == ERR_OK) {
01260       conn->write_offset += len;
01261       if (conn->write_offset == conn->current_msg->msg.w.len) {
01262         /* everything was written */
01263         write_finished = 1;
01264         conn->write_offset = 0;
01265       }
01266       tcp_output(conn->pcb.tcp);
01267     } else if (err == ERR_MEM) {
01268       /* If ERR_MEM, we wait for sent_tcp or poll_tcp to be called
01269          we do NOT return to the application thread, since ERR_MEM is
01270          only a temporary error! */
01271 
01272       /* tcp_write returned ERR_MEM, try tcp_output anyway */
01273       tcp_output(conn->pcb.tcp);
01274 
01275   #if LWIP_TCPIP_CORE_LOCKING
01276       conn->flags |= NETCONN_FLAG_WRITE_DELAYED;
01277   #endif
01278     } else {
01279       /* On errors != ERR_MEM, we don't try writing any more but return
01280          the error to the application thread. */
01281       write_finished = 1;
01282     }
01283   }
01284 
01285   if (write_finished) {
01286     /* everything was written: set back connection state
01287        and back to application task */
01288     conn->current_msg->err = err;
01289     conn->current_msg = NULL;
01290     conn->state = NETCONN_NONE;
01291 #if LWIP_TCPIP_CORE_LOCKING
01292     if ((conn->flags & NETCONN_FLAG_WRITE_DELAYED) != 0)
01293 #endif
01294     {
01295       sys_sem_signal(&conn->op_completed);
01296     }
01297   }
01298 #if LWIP_TCPIP_CORE_LOCKING
01299   else
01300     return ERR_MEM;
01301 #endif
01302   return ERR_OK;
01303 }
01304 #endif /* LWIP_TCP */
01305 
01306 /**
01307  * Send some data on a TCP pcb contained in a netconn
01308  * Called from netconn_write
01309  *
01310  * @param msg the api_msg_msg pointing to the connection
01311  */
01312 void
01313 do_write(struct api_msg_msg *msg)
01314 {
01315   if (ERR_IS_FATAL(msg->conn->last_err)) {
01316     msg->err = msg->conn->last_err;
01317   } else {
01318     if (msg->conn->type == NETCONN_TCP) {
01319 #if LWIP_TCP
01320       if (msg->conn->state != NETCONN_NONE) {
01321         /* netconn is connecting, closing or in blocking write */
01322         msg->err = ERR_INPROGRESS;
01323       } else if (msg->conn->pcb.tcp != NULL) {
01324         msg->conn->state = NETCONN_WRITE;
01325         /* set all the variables used by do_writemore */
01326         LWIP_ASSERT("already writing or closing", msg->conn->current_msg == NULL &&
01327           msg->conn->write_offset == 0);
01328         LWIP_ASSERT("msg->msg.w.len != 0", msg->msg.w.len != 0);
01329         msg->conn->current_msg = msg;
01330         msg->conn->write_offset = 0;
01331 #if LWIP_TCPIP_CORE_LOCKING
01332         msg->conn->flags &= ~NETCONN_FLAG_WRITE_DELAYED;
01333         if (do_writemore(msg->conn) != ERR_OK) {
01334           LWIP_ASSERT("state!", msg->conn->state == NETCONN_WRITE);
01335           UNLOCK_TCPIP_CORE();
01336           sys_arch_sem_wait(&msg->conn->op_completed, 0);
01337           LOCK_TCPIP_CORE();
01338           LWIP_ASSERT("state!", msg->conn->state == NETCONN_NONE);
01339         }
01340 #else /* LWIP_TCPIP_CORE_LOCKING */
01341         do_writemore(msg->conn);
01342 #endif /* LWIP_TCPIP_CORE_LOCKING */
01343         /* for both cases: if do_writemore was called, don't ACK the APIMSG
01344            since do_writemore ACKs it! */
01345         return;
01346       } else {
01347         msg->err = ERR_CONN;
01348       }
01349 #else /* LWIP_TCP */
01350       msg->err = ERR_VAL;
01351 #endif /* LWIP_TCP */
01352 #if (LWIP_UDP || LWIP_RAW)
01353     } else {
01354       msg->err = ERR_VAL;
01355 #endif /* (LWIP_UDP || LWIP_RAW) */
01356     }
01357   }
01358   TCPIP_APIMSG_ACK(msg);
01359 }
01360 
01361 /**
01362  * Return a connection's local or remote address
01363  * Called from netconn_getaddr
01364  *
01365  * @param msg the api_msg_msg pointing to the connection
01366  */
01367 void
01368 do_getaddr(struct api_msg_msg *msg)
01369 {
01370   if (msg->conn->pcb.ip != NULL) {
01371     *(msg->msg.ad.ipaddr) = (msg->msg.ad.local ? msg->conn->pcb.ip->local_ip :
01372                              msg->conn->pcb.ip->remote_ip);
01373 
01374     msg->err = ERR_OK;
01375     switch (NETCONNTYPE_GROUP(msg->conn->type)) {
01376 #if LWIP_RAW
01377     case NETCONN_RAW:
01378       if (msg->msg.ad.local) {
01379         *(msg->msg.ad.port) = msg->conn->pcb.raw->protocol;
01380       } else {
01381         /* return an error as connecting is only a helper for upper layers */
01382         msg->err = ERR_CONN;
01383       }
01384       break;
01385 #endif /* LWIP_RAW */
01386 #if LWIP_UDP
01387     case NETCONN_UDP:
01388       if (msg->msg.ad.local) {
01389         *(msg->msg.ad.port) = msg->conn->pcb.udp->local_port;
01390       } else {
01391         if ((msg->conn->pcb.udp->flags & UDP_FLAGS_CONNECTED) == 0) {
01392           msg->err = ERR_CONN;
01393         } else {
01394           *(msg->msg.ad.port) = msg->conn->pcb.udp->remote_port;
01395         }
01396       }
01397       break;
01398 #endif /* LWIP_UDP */
01399 #if LWIP_TCP
01400     case NETCONN_TCP:
01401       *(msg->msg.ad.port) = (msg->msg.ad.local?msg->conn->pcb.tcp->local_port:msg->conn->pcb.tcp->remote_port);
01402       break;
01403 #endif /* LWIP_TCP */
01404     default:
01405       LWIP_ASSERT("invalid netconn_type", 0);
01406       break;
01407     }
01408   } else {
01409     msg->err = ERR_CONN;
01410   }
01411   TCPIP_APIMSG_ACK(msg);
01412 }
01413 
01414 /**
01415  * Close a TCP pcb contained in a netconn
01416  * Called from netconn_close
01417  *
01418  * @param msg the api_msg_msg pointing to the connection
01419  */
01420 void
01421 do_close(struct api_msg_msg *msg)
01422 {
01423 #if LWIP_TCP
01424   /* @todo: abort running write/connect? */
01425   if ((msg->conn->state != NETCONN_NONE) && (msg->conn->state != NETCONN_LISTEN)) {
01426     /* this only happens for TCP netconns */
01427     LWIP_ASSERT("msg->conn->type == NETCONN_TCP", msg->conn->type == NETCONN_TCP);
01428     msg->err = ERR_INPROGRESS;
01429   } else if ((msg->conn->pcb.tcp != NULL) && (msg->conn->type == NETCONN_TCP)) {
01430     if ((msg->msg.sd.shut != NETCONN_SHUT_RDWR) && (msg->conn->state == NETCONN_LISTEN)) {
01431       /* LISTEN doesn't support half shutdown */
01432       msg->err = ERR_CONN;
01433     } else {
01434       if (msg->msg.sd.shut & NETCONN_SHUT_RD) {
01435         /* Drain and delete mboxes */
01436         netconn_drain(msg->conn);
01437       }
01438       LWIP_ASSERT("already writing or closing", msg->conn->current_msg == NULL &&
01439         msg->conn->write_offset == 0);
01440       msg->conn->state = NETCONN_CLOSE;
01441       msg->conn->current_msg = msg;
01442       do_close_internal(msg->conn);
01443       /* for tcp netconns, do_close_internal ACKs the message */
01444       return;
01445     }
01446   } else
01447 #endif /* LWIP_TCP */
01448   {
01449     msg->err = ERR_VAL;
01450   }
01451   sys_sem_signal(&msg->conn->op_completed);
01452 }
01453 
01454 #if LWIP_IGMP
01455 /**
01456  * Join multicast groups for UDP netconns.
01457  * Called from netconn_join_leave_group
01458  *
01459  * @param msg the api_msg_msg pointing to the connection
01460  */
01461 void
01462 do_join_leave_group(struct api_msg_msg *msg)
01463 { 
01464   if (ERR_IS_FATAL(msg->conn->last_err)) {
01465     msg->err = msg->conn->last_err;
01466   } else {
01467     if (msg->conn->pcb.tcp != NULL) {
01468       if (NETCONNTYPE_GROUP(msg->conn->type) == NETCONN_UDP) {
01469 #if LWIP_UDP
01470         if (msg->msg.jl.join_or_leave == NETCONN_JOIN) {
01471           msg->err = igmp_joingroup(msg->msg.jl.netif_addr, msg->msg.jl.multiaddr);
01472         } else {
01473           msg->err = igmp_leavegroup(msg->msg.jl.netif_addr, msg->msg.jl.multiaddr);
01474         }
01475 #endif /* LWIP_UDP */
01476 #if (LWIP_TCP || LWIP_RAW)
01477       } else {
01478         msg->err = ERR_VAL;
01479 #endif /* (LWIP_TCP || LWIP_RAW) */
01480       }
01481     } else {
01482       msg->err = ERR_CONN;
01483     }
01484   }
01485   TCPIP_APIMSG_ACK(msg);
01486 }
01487 #endif /* LWIP_IGMP */
01488 
01489 #if LWIP_DNS
01490 /**
01491  * Callback function that is called when DNS name is resolved
01492  * (or on timeout). A waiting application thread is waked up by
01493  * signaling the semaphore.
01494  */
01495 static void
01496 do_dns_found(const char *name, ip_addr_t *ipaddr, void *arg)
01497 {
01498   struct dns_api_msg *msg = (struct dns_api_msg*)arg;
01499 
01500   LWIP_ASSERT("DNS response for wrong host name", strcmp(msg->name, name) == 0);
01501   LWIP_UNUSED_ARG(name);
01502 
01503   if (ipaddr == NULL) {
01504     /* timeout or memory error */
01505     *msg->err = ERR_VAL;
01506   } else {
01507     /* address was resolved */
01508     *msg->err = ERR_OK;
01509     *msg->addr = *ipaddr;
01510   }
01511   /* wake up the application task waiting in netconn_gethostbyname */
01512   sys_sem_signal(msg->sem);
01513 }
01514 
01515 /**
01516  * Execute a DNS query
01517  * Called from netconn_gethostbyname
01518  *
01519  * @param arg the dns_api_msg pointing to the query
01520  */
01521 void
01522 do_gethostbyname(void *arg)
01523 {
01524   struct dns_api_msg *msg = (struct dns_api_msg*)arg;
01525 
01526   *msg->err = dns_gethostbyname(msg->name, msg->addr, do_dns_found, msg);
01527   if (*msg->err != ERR_INPROGRESS) {
01528     /* on error or immediate success, wake up the application
01529      * task waiting in netconn_gethostbyname */
01530     sys_sem_signal(msg->sem);
01531   }
01532 }
01533 #endif /* LWIP_DNS */
01534 
01535 #endif /* LWIP_NETCONN */