bertos/net/xmodem.c

   1 /**
   2  * \file
   3  * <!--
   4  * This file is part of BeRTOS.
   5  *
   6  * Bertos is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  * As a special exception, you may use this file as part of a free software
  21  * library without restriction.  Specifically, if other files instantiate
  22  * templates or use macros or inline functions from this file, or you compile
  23  * this file and link it with other files to produce an executable, this
  24  * file does not by itself cause the resulting executable to be covered by
  25  * the GNU General Public License.  This exception does not however
  26  * invalidate any other reasons why the executable file might be covered by
  27  * the GNU General Public License.
  28  *
  29  * Copyright 2004, 2005, 2006, 2007 Develer S.r.l. (http://www.develer.com/)
  30  * Copyright 1999, 2001 Bernie Innocenti <bernie@codewiz.org>
  31  *
  32  * -->
  33  *
  34  * \brief X-Modem serial transmission protocol (implementation)
  35  *
  36  * Supports the CRC-16 and 1K-blocks variants of the standard.
  37  * \see ymodem.txt for the protocol description.
  38  *
  39  * \todo Break xmodem_send() and xmodem_recv() in smaller functions.
  40  *
  41  * \version $Id$
  42  *
  43  * \author Bernie Innocenti <bernie@codewiz.org>
  44  * \author Francesco Sacchi <batt@develer.com>
  45  */
  46
  47
  48 #include "xmodem.h"
  49
  50 #include <cfg/debug.h>
  51 #include "cfg/cfg_xmodem.h"
  52
  53 #include <drv/ser.h>
  54
  55 #include <algo/crc.h>
  56
  57 #include <string.h> /* for memset() */
  58
  59 /**
  60  * \name Protocol control codes
  61  * \{
  62  */
  63 #define XM_SOH  0x01  /**< Start Of Header (128-byte block) */
  64 #define XM_STX  0x02  /**< Start Of Header (1024-byte block) */
  65 #define XM_EOT  0x04  /**< End Of Transmission */
  66 #define XM_ACK  0x06  /**< Acknowledge block */
  67 #define XM_NAK  0x15  /**< Negative Acknowledge */
  68 #define XM_C    0x43  /**< Request CRC-16 transmission */
  69 #define XM_CAN  0x18  /**< CANcel transmission */
  70 /*\}*/
  71
  72 #if CONFIG_XMODEM_1KCRC == 1
  73         #define XM_BUFSIZE       1024  /**< 1024 bytes of block buffer */
  74 #else
  75         #define XM_BUFSIZE       128   /**< 128 bytes of block buffer */
  76 #endif
  77
  78
  79 #if CONFIG_XMODEM_RECV
  80 /**
  81  * \brief Receive a file using the XModem protocol.
  82  *
  83  * \param port Serial port to use for transfer
  84  * \param fd Destination file
  85  *
  86  * \note This function allocates a large amount of stack (\see XM_BUFSIZE).
  87  */
  88 bool xmodem_recv(struct Serial *port, KFile *fd)
  89 {
  90         char block_buffer[XM_BUFSIZE]; /* Buffer to hold a block of data */
  91         int c, i, blocksize;
  92         int blocknr = 0, last_block_done = 0, retries = 0;
  93         char *buf;
  94         uint8_t checksum;
  95         uint16_t crc;
  96         bool purge = false;
  97         bool usecrc = true;
  98
  99
 100         XMODEM_PROGRESS("Starting Transfer...\n");
 101         purge = true;
 102         kfile_clearerr(&port->fd);
 103
 104         /* Send initial NAK to start transmission */
 105         for(;;)
 106         {
 107                 if (XMODEM_CHECK_ABORT)
 108                 {
 109                         kfile_putc(XM_CAN, &port->fd);
 110                         kfile_putc(XM_CAN, &port->fd);
 111                         XMODEM_PROGRESS("Transfer aborted\n");
 112                         return false;
 113                 }
 114
 115                 /*
 116                  * Discard incoming input until a timeout occurs, then send
 117                  * a NAK to the transmitter.
 118                  */
 119                 if (purge)
 120                 {
 121                         purge = false;
 122
 123                         if (kfile_error(&port->fd))
 124                                 XMODEM_PROGRESS("Retries %d\n", retries);
 125
 126                         ser_resync(port, 200);
 127                         retries++;
 128
 129                         if (retries >= CONFIG_XMODEM_MAXRETRIES)
 130                         {
 131                                 kfile_putc(XM_CAN, &port->fd);
 132                                 kfile_putc(XM_CAN, &port->fd);
 133                                 XMODEM_PROGRESS("Transfer aborted\n");
 134                                 return false;
 135                         }
 136
 137                         /* Transmission start? */
 138                         if (blocknr == 0)
 139                         {
 140                                 if (retries < CONFIG_XMODEM_MAXCRCRETRIES)
 141                                 {
 142                                         XMODEM_PROGRESS("Request Tx (CRC)\n");
 143                                         kfile_putc(XM_C, &port->fd);
 144                                 }
 145                                 else
 146                                 {
 147                                         /* Give up with CRC and fall back to checksum */
 148                                         usecrc = false;
 149                                         XMODEM_PROGRESS("Request Tx (BCC)\n");
 150                                         kfile_putc(XM_NAK, &port->fd);
 151                                 }
 152                         }
 153                         else
 154                                 kfile_putc(XM_NAK, &port->fd);
 155                 }
 156
 157                 switch (kfile_getc(&port->fd))
 158                 {
 159                 #if XM_BUFSIZE >= 1024
 160                 case XM_STX:  /* Start of header (1024-byte block) */
 161                         blocksize = 1024;
 162                         goto getblock;
 163                 #endif
 164
 165                 case XM_SOH:  /* Start of header (128-byte block) */
 166                         blocksize = 128;
 167                         /* Needed to avoid warning if XM_BUFSIZE < 1024 */
 168
 169                 getblock:
 170                         /* Get block number */
 171                         c = kfile_getc(&port->fd);
 172
 173                         /* Check complemented block number */
 174                         if ((~c & 0xff) != kfile_getc(&port->fd))
 175                         {
 176                                 XMODEM_PROGRESS("Bad blk (%d)\n", c);
 177                                 purge = true;
 178                                 break;
 179                         }
 180
 181                         /* Determine which block is being sent */
 182                         if (c == (blocknr & 0xff))
 183                                 /* Last block repeated */
 184                                 XMODEM_PROGRESS("Repeat blk %d\n", blocknr);
 185                         else if (c == ((blocknr + 1) & 0xff))
 186                                 /* Next block */
 187                                 XMODEM_PROGRESS("Recv blk %d\n", ++blocknr);
 188                         else
 189                         {
 190                                 /* Sync lost */
 191                                 XMODEM_PROGRESS("Sync lost (%d/%d)\n", c, blocknr);
 192                                 purge = true;
 193                                 break;
 194                         }
 195
 196                         buf = block_buffer;     /* Reset pointer to start of buffer */
 197                         checksum = 0;
 198                         crc = 0;
 199                         for (i = 0; i < blocksize; i++)
 200                         {
 201                                 if ((c = kfile_getc(&port->fd)) == EOF)
 202                                 {
 203                                         purge = true;
 204                                         break;
 205                                 }
 206
 207                                 /* Store in buffer */
 208                                 *buf++ = (char)c;
 209
 210                                 /* Calculate block checksum or CRC */
 211                                 if (usecrc)
 212                                         crc = UPDCRC16(c, crc);
 213                                 else
 214                                         checksum += (char)c;
 215                         }
 216
 217                         if (purge)
 218                                 break;
 219
 220                         /* Get the checksum byte or the CRC-16 MSB */
 221                         if ((c = kfile_getc(&port->fd)) == EOF)
 222                         {
 223                                 purge = true;
 224                                 break;
 225                         }
 226
 227                         if (usecrc)
 228                         {
 229                                 crc = UPDCRC16(c, crc);
 230
 231                                 /* Get CRC-16 LSB */
 232                                 if ((c = kfile_getc(&port->fd)) == EOF)
 233                                 {
 234                                         purge = true;
 235                                         break;
 236                                 }
 237
 238                                 crc = UPDCRC16(c, crc);
 239
 240                                 if (crc)
 241                                 {
 242                                         XMODEM_PROGRESS("Bad CRC: %04x\n", crc);
 243                                         purge = true;
 244                                         break;
 245                                 }
 246                         }
 247                         /* Compare the checksum */
 248                         else if (c != checksum)
 249                         {
 250                                 XMODEM_PROGRESS("Bad sum: %04x/%04x\n", checksum, c);
 251                                 purge = true;
 252                                 break;
 253                         }
 254
 255                         /*
 256                          * Avoid flushing the same block twice.
 257                          * This could happen when the sender does not receive our
 258                          * acknowledge and resends the same block.
 259                          */
 260                         if (last_block_done < blocknr)
 261                         {
 262                                 /* Call user function to flush the buffer */
 263                                 if (kfile_write(fd, block_buffer, blocksize))
 264                                 {
 265                                         /* Acknowledge block and clear error counter */
 266                                         kfile_putc(XM_ACK, &port->fd);
 267                                         retries = 0;
 268                                         last_block_done = blocknr;
 269                                 }
 270                                 else
 271                                 {
 272                                         /* User callback failed: abort transfer immediately */
 273                                         retries = CONFIG_XMODEM_MAXRETRIES;
 274                                         purge = true;
 275                                 }
 276                         }
 277                         break;
 278
 279                 case XM_EOT:    /* End of transmission */
 280                         kfile_putc(XM_ACK, &port->fd);
 281                         XMODEM_PROGRESS("Transfer completed\n");
 282                         return true;
 283
 284                 case EOF: /* Timeout or serial error */
 285                         purge = true;
 286                         break;
 287
 288                 default:
 289                         XMODEM_PROGRESS("Skipping garbage\n");
 290                         purge = true;
 291                         break;
 292                 }
 293         } /* End forever */
 294 }
 295 #endif
 296
 297
 298 #if CONFIG_XMODEM_SEND
 299 /**
 300  * \brief Transmit some data using the XModem protocol.
 301  *
 302  * \param port Serial port to use for transfer
 303  * \param fd Source file
 304  *
 305  * \note This function allocates a large amount of stack for
 306  *       the XModem transfer buffer (\see XM_BUFSIZE).
 307  */
 308 bool xmodem_send(struct Serial *port, KFile *fd)
 309 {
 310         char block_buffer[XM_BUFSIZE]; /* Buffer to hold a block of data */
 311         size_t size = -1;
 312         int blocknr = 1, retries = 0, c, i;
 313         bool proceed, usecrc = false;
 314         uint16_t crc;
 315         uint8_t sum;
 316
 317         /*
 318          * Reading a block can be very slow, so we read the first block early
 319          * to avoid receiving double XM_C char.
 320          * This could happen if we check for XM_C and then read the block, giving
 321          * the receiving device time to send another XM_C char misinterpretating
 322          * the blocks sent.
 323          */
 324         size = kfile_read(fd, block_buffer, XM_BUFSIZE);
 325
 326         kfile_clearerr(&port->fd);
 327         ser_purge(port);
 328         XMODEM_PROGRESS("Wait remote host\n");
 329
 330         for(;;)
 331         {
 332                 proceed = false;
 333                 do
 334                 {
 335                         if (XMODEM_CHECK_ABORT)
 336                                 return false;
 337
 338                         switch (c = kfile_getc(&port->fd))
 339                         {
 340                         case XM_NAK:
 341                                 XMODEM_PROGRESS("Resend blk %d\n", blocknr);
 342                                 proceed = true;
 343                                 break;
 344
 345                         case XM_C:
 346                                 if (c == XM_C)
 347                                 {
 348                                         XMODEM_PROGRESS("Tx start (CRC)\n");
 349                                         usecrc = true;
 350                                 }
 351                                 else
 352                                         XMODEM_PROGRESS("Tx start (BCC)\n");
 353
 354                                 proceed = true;
 355                                 break;
 356
 357                         case XM_ACK:
 358                                 /* End of transfer? */
 359                                 if (!size)
 360                                         return true;
 361
 362                                 /* Call user function to read in one block */
 363                                 size = kfile_read(fd, block_buffer, XM_BUFSIZE);
 364                                 XMODEM_PROGRESS("Send blk %d\n", blocknr);
 365                                 blocknr++;
 366                                 retries = 0;
 367                                 proceed = true;
 368                                 break;
 369
 370                         case EOF:
 371                                 kfile_clearerr(&port->fd);
 372                                 retries++;
 373                                 XMODEM_PROGRESS("Retries %d\n", retries);
 374                                 if (retries <= CONFIG_XMODEM_MAXRETRIES)
 375                                         break;
 376                                 /* falling through! */
 377
 378                         case XM_CAN:
 379                                 XMODEM_PROGRESS("Transfer aborted\n");
 380                                 return false;
 381
 382                         default:
 383                                 XMODEM_PROGRESS("Skipping garbage\n");
 384                                 break;
 385                         }
 386                 }
 387                 while (!proceed);
 388
 389                 if (!size)
 390                 {
 391                         kfile_putc(XM_EOT, &port->fd);
 392                         continue;
 393                 }
 394
 395                 /* Pad block with 0xFF if it's partially full */
 396                 memset(block_buffer + size, 0xFF, XM_BUFSIZE - size);
 397
 398                 /* Send block header (STX, blocknr, ~blocknr) */
 399                 #if XM_BUFSIZE == 128
 400                         kfile_putc(XM_SOH, &port->fd);
 401                 #else
 402                         kfile_putc(XM_STX, &port->fd);
 403                 #endif
 404                 kfile_putc(blocknr & 0xFF, &port->fd);
 405                 kfile_putc(~blocknr & 0xFF, &port->fd);
 406
 407                 /* Send block and compute its CRC/checksum */
 408                 sum = 0;
 409                 crc = 0;
 410                 for (i = 0; i < XM_BUFSIZE; i++)
 411                 {
 412                         kfile_putc(block_buffer[i], &port->fd);
 413                         crc = UPDCRC16(block_buffer[i], crc);
 414                         sum += block_buffer[i];
 415                 }
 416
 417                 /* Send CRC/Checksum */
 418                 if (usecrc)
 419                 {
 420                         crc = UPDCRC16(0, crc);
 421                         crc = UPDCRC16(0, crc);
 422                         kfile_putc(crc >> 8, &port->fd);
 423                         kfile_putc(crc & 0xFF, &port->fd);
 424                 }
 425                 else
 426                         kfile_putc(sum, &port->fd);
 427         }
 428 }
 429 #endif