FreeRTOS/Common/ethernet/FreeTCPIP/psock.c

   1 /*
   2  * Copyright (c) 2004, Swedish Institute of Computer Science.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the Institute nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * This file is part of the uIP TCP/IP stack
  30  *
  31  * Author: Adam Dunkels <adam@sics.se>
  32  *
  33  * $Id: psock.c,v 1.2 2006/06/12 08:00:30 adam Exp $
  34  */
  35
  36 #include <stdio.h>
  37 #include <string.h>
  38
  39 #include "net/uipopt.h"
  40 #include "net/psock.h"
  41 #include "net/uip.h"
  42
  43 #define STATE_NONE 0
  44 #define STATE_ACKED 1
  45 #define STATE_READ 2
  46 #define STATE_BLOCKED_NEWDATA 3
  47 #define STATE_BLOCKED_CLOSE 4
  48 #define STATE_BLOCKED_SEND 5
  49 #define STATE_DATA_SENT 6
  50
  51 /*
  52  * Return value of the buffering functions that indicates that a
  53  * buffer was not filled by incoming data.
  54  *
  55  */
  56 #define BUF_NOT_FULL 0
  57 #define BUF_NOT_FOUND 0
  58
  59 /*
  60  * Return value of the buffering functions that indicates that a
  61  * buffer was completely filled by incoming data.
  62  *
  63  */
  64 #define BUF_FULL 1
  65
  66 /*
  67  * Return value of the buffering functions that indicates that an
  68  * end-marker byte was found.
  69  *
  70  */
  71 #define BUF_FOUND 2
  72
  73 /*---------------------------------------------------------------------------*/
  74 static void
  75 buf_setup(struct psock_buf *buf,
  76           u8_t *bufptr, u16_t bufsize)
  77 {
  78   buf->ptr = bufptr;
  79   buf->left = bufsize;
  80 }
  81 /*---------------------------------------------------------------------------*/
  82 static u8_t
  83 buf_bufdata(struct psock_buf *buf, u16_t len,
  84             u8_t **dataptr, u16_t *datalen)
  85 {
  86   ( void ) len;
  87   if(*datalen < buf->left) {
  88     memcpy(buf->ptr, *dataptr, *datalen);
  89     buf->ptr += *datalen;
  90     buf->left -= *datalen;
  91     *dataptr += *datalen;
  92     *datalen = 0;
  93     return BUF_NOT_FULL;
  94   } else if(*datalen == buf->left) {
  95     memcpy(buf->ptr, *dataptr, *datalen);
  96     buf->ptr += *datalen;
  97     buf->left = 0;
  98     *dataptr += *datalen;
  99     *datalen = 0;
 100     return BUF_FULL;
 101   } else {
 102     memcpy(buf->ptr, *dataptr, buf->left);
 103     buf->ptr += buf->left;
 104     *datalen -= buf->left;
 105     *dataptr += buf->left;
 106     buf->left = 0;
 107     return BUF_FULL;
 108   }
 109 }
 110 /*---------------------------------------------------------------------------*/
 111 static u8_t
 112 buf_bufto(register struct psock_buf *buf, u8_t endmarker,
 113           register u8_t **dataptr, register u16_t *datalen)
 114 {
 115   u8_t c;
 116   while(buf->left > 0 && *datalen > 0) {
 117     c = *buf->ptr = **dataptr;
 118     ++*dataptr;
 119     ++buf->ptr;
 120     --*datalen;
 121     --buf->left;
 122
 123     if(c == endmarker) {
 124       return BUF_FOUND;
 125     }
 126   }
 127
 128   if(*datalen == 0) {
 129     return BUF_NOT_FOUND;
 130   }
 131
 132   while(*datalen > 0) {
 133     c = **dataptr;
 134     --*datalen;
 135     ++*dataptr;
 136
 137     if(c == endmarker) {
 138       return BUF_FOUND | BUF_FULL;
 139     }
 140   }
 141
 142   return BUF_FULL;
 143 }
 144 /*---------------------------------------------------------------------------*/
 145 static char
 146 send_data(register struct psock *s)
 147 {
 148   if(s->state != STATE_DATA_SENT || uip_rexmit()) {
 149     if(s->sendlen > uip_mss()) {
 150       uip_send(s->sendptr, uip_mss());
 151     } else {
 152       uip_send(s->sendptr, s->sendlen);
 153     }
 154     s->state = STATE_DATA_SENT;
 155     return 1;
 156   }
 157   return 0;
 158 }
 159 /*---------------------------------------------------------------------------*/
 160 static char
 161 data_acked(register struct psock *s)
 162 {
 163   if(s->state == STATE_DATA_SENT && uip_acked()) {
 164     if(s->sendlen > uip_mss()) {
 165       s->sendlen -= uip_mss();
 166       s->sendptr += uip_mss();
 167     } else {
 168       s->sendptr += s->sendlen;
 169       s->sendlen = 0;
 170     }
 171     s->state = STATE_ACKED;
 172     return 1;
 173   }
 174   return 0;
 175 }
 176 /*---------------------------------------------------------------------------*/
 177 PT_THREAD(psock_send(register struct psock *s, const char *buf,
 178                      unsigned int len))
 179 {
 180   PT_BEGIN(&s->psockpt);
 181
 182   /* If there is no data to send, we exit immediately. */
 183   if(len == 0) {
 184     PT_EXIT(&s->psockpt);
 185   }
 186
 187   /* Save the length of and a pointer to the data that is to be
 188      sent. */
 189   s->sendptr = (unsigned char*)buf;
 190   s->sendlen = (unsigned short)len;
 191
 192   s->state = STATE_NONE;
 193
 194   /* We loop here until all data is sent. The s->sendlen variable is
 195      updated by the data_sent() function. */
 196   while(s->sendlen > 0) {
 197
 198     /*
 199      * The condition for this PT_WAIT_UNTIL is a little tricky: the
 200      * protothread will wait here until all data has been acknowledged
 201      * (data_acked() returns true) and until all data has been sent
 202      * (send_data() returns true). The two functions data_acked() and
 203      * send_data() must be called in succession to ensure that all
 204      * data is sent. Therefore the & operator is used instead of the
 205      * && operator, which would cause only the data_acked() function
 206      * to be called when it returns false.
 207      */
 208     PT_WAIT_UNTIL(&s->psockpt, data_acked(s) & send_data(s));
 209   }
 210
 211   s->state = STATE_NONE;
 212
 213   PT_END(&s->psockpt);
 214 }
 215 /*---------------------------------------------------------------------------*/
 216 PT_THREAD(psock_generator_send(register struct psock *s,
 217                                unsigned short (*generate)(void *), void *arg))
 218 {
 219   PT_BEGIN(&s->psockpt);
 220
 221   /* Ensure that there is a generator function to call. */
 222   if(generate == NULL) {
 223     PT_EXIT(&s->psockpt);
 224   }
 225
 226   /* Call the generator function to generate the data in the
 227      uip_appdata buffer. */
 228   s->sendlen = generate(arg);
 229   s->sendptr = uip_appdata;
 230
 231   s->state = STATE_NONE;
 232   do {
 233     /* Call the generator function again if we are called to perform a
 234        retransmission. */
 235     if(uip_rexmit()) {
 236       generate(arg);
 237     }
 238     /* Wait until all data is sent and acknowledged. */
 239     PT_WAIT_UNTIL(&s->psockpt, data_acked(s) & send_data(s));
 240   } while(s->sendlen > 0);
 241
 242   s->state = STATE_NONE;
 243
 244   PT_END(&s->psockpt);
 245 }
 246 /*---------------------------------------------------------------------------*/
 247 u16_t
 248 psock_datalen(struct psock *psock)
 249 {
 250   return psock->bufsize - psock->buf.left;
 251 }
 252 /*---------------------------------------------------------------------------*/
 253 char
 254 psock_newdata(struct psock *s)
 255 {
 256   if(s->readlen > 0) {
 257     /* There is data in the uip_appdata buffer that has not yet been
 258        read with the PSOCK_READ functions. */
 259     return 1;
 260   } else if(s->state == STATE_READ) {
 261     /* All data in uip_appdata buffer already consumed. */
 262     s->state = STATE_BLOCKED_NEWDATA;
 263     return 0;
 264   } else if(uip_newdata()) {
 265     /* There is new data that has not been consumed. */
 266     return 1;
 267   } else {
 268     /* There is no new data. */
 269     return 0;
 270   }
 271 }
 272 /*---------------------------------------------------------------------------*/
 273 PT_THREAD(psock_readto(register struct psock *psock, unsigned char c))
 274 {
 275   PT_BEGIN(&psock->psockpt);
 276
 277   buf_setup(&psock->buf, (unsigned char*)psock->bufptr, psock->bufsize);
 278
 279   /* XXX: Should add buf_checkmarker() before do{} loop, if
 280      incoming data has been handled while waiting for a write. */
 281
 282   do {
 283     if(psock->readlen == 0) {
 284       PT_WAIT_UNTIL(&psock->psockpt, psock_newdata(psock));
 285       psock->state = STATE_READ;
 286       psock->readptr = (u8_t *)uip_appdata;
 287       psock->readlen = uip_datalen();
 288     }
 289   } while((buf_bufto(&psock->buf, c,
 290                      &psock->readptr,
 291                      &psock->readlen) & BUF_FOUND) == 0);
 292
 293   if(psock_datalen(psock) == 0) {
 294     psock->state = STATE_NONE;
 295     PT_RESTART(&psock->psockpt);
 296   }
 297   PT_END(&psock->psockpt);
 298 }
 299 /*---------------------------------------------------------------------------*/
 300 PT_THREAD(psock_readbuf(register struct psock *psock))
 301 {
 302   PT_BEGIN(&psock->psockpt);
 303
 304   buf_setup(&psock->buf, (unsigned char * ) psock->bufptr, psock->bufsize);
 305
 306   /* XXX: Should add buf_checkmarker() before do{} loop, if
 307      incoming data has been handled while waiting for a write. */
 308
 309   do {
 310     if(psock->readlen == 0) {
 311       PT_WAIT_UNTIL(&psock->psockpt, psock_newdata(psock));
 312       psock->state = STATE_READ;
 313       psock->readptr = (u8_t *)uip_appdata;
 314       psock->readlen = uip_datalen();
 315     }
 316   } while(buf_bufdata(&psock->buf, psock->bufsize,
 317                          &psock->readptr,
 318                          &psock->readlen) != BUF_FULL);
 319
 320   if(psock_datalen(psock) == 0) {
 321     psock->state = STATE_NONE;
 322     PT_RESTART(&psock->psockpt);
 323   }
 324   PT_END(&psock->psockpt);
 325 }
 326 /*---------------------------------------------------------------------------*/
 327 void
 328 psock_init(register struct psock *psock, char *buffer, unsigned int buffersize)
 329 {
 330   psock->state = STATE_NONE;
 331   psock->readlen = 0;
 332   psock->bufptr = buffer;
 333   psock->bufsize = buffersize;
 334   buf_setup(&psock->buf, (unsigned char*) buffer, buffersize);
 335   PT_INIT(&psock->pt);
 336   PT_INIT(&psock->psockpt);
 337 }
 338 /*---------------------------------------------------------------------------*/