common/xyzModem.c

   1 /*
   2  *==========================================================================
   3  *
   4  *      xyzModem.c
   5  *
   6  *      RedBoot stream handler for xyzModem protocol
   7  *
   8  *==========================================================================
   9  *####ECOSGPLCOPYRIGHTBEGIN####
  10  * -------------------------------------------
  11  * This file is part of eCos, the Embedded Configurable Operating System.
  12  * Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
  13  * Copyright (C) 2002 Gary Thomas
  14  *
  15  * eCos is free software; you can redistribute it and/or modify it under
  16  * the terms of the GNU General Public License as published by the Free
  17  * Software Foundation; either version 2 or (at your option) any later version.
  18  *
  19  * eCos is distributed in the hope that it will be useful, but WITHOUT ANY
  20  * WARRANTY; without even the implied warranty of MERCHANTABILITY or
  21  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  22  * for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License along
  25  * with eCos; if not, write to the Free Software Foundation, Inc.,
  26  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  27  *
  28  * As a special exception, if other files instantiate templates or use macros
  29  * or inline functions from this file, or you compile this file and link it
  30  * with other works to produce a work based on this file, this file does not
  31  * by itself cause the resulting work to be covered by the GNU General Public
  32  * License. However the source code for this file must still be made available
  33  * in accordance with section (3) of the GNU General Public License.
  34  *
  35  * This exception does not invalidate any other reasons why a work based on
  36  * this file might be covered by the GNU General Public License.
  37  *
  38  * Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
  39  * at http: *sources.redhat.com/ecos/ecos-license/
  40  * -------------------------------------------
  41  *####ECOSGPLCOPYRIGHTEND####
  42  *==========================================================================
  43  *#####DESCRIPTIONBEGIN####
  44  *
  45  * Author(s):    gthomas
  46  * Contributors: gthomas, tsmith, Yoshinori Sato
  47  * Date:         2000-07-14
  48  * Purpose:
  49  * Description:
  50  *
  51  * This code is part of RedBoot (tm).
  52  *
  53  *####DESCRIPTIONEND####
  54  *
  55  *==========================================================================
  56  */
  57 #include <common.h>
  58 #include <xyzModem.h>
  59 #include <stdarg.h>
  60 #include <crc.h>
  61
  62 /* Assumption - run xyzModem protocol over the console port */
  63
  64 /* Values magic to the protocol */
  65 #define SOH 0x01
  66 #define STX 0x02
  67 #define EOT 0x04
  68 #define ACK 0x06
  69 #define BSP 0x08
  70 #define NAK 0x15
  71 #define CAN 0x18
  72 #define EOF 0x1A                /* ^Z for DOS officionados */
  73
  74 #define USE_YMODEM_LENGTH
  75
  76 /* Data & state local to the protocol */
  77 static struct
  78 {
  79 #ifdef REDBOOT
  80   hal_virtual_comm_table_t *__chan;
  81 #else
  82   int *__chan;
  83 #endif
  84   unsigned char pkt[1024], *bufp;
  85   unsigned char blk, cblk, crc1, crc2;
  86   unsigned char next_blk;       /* Expected block */
  87   int len, mode, total_retries;
  88   int total_SOH, total_STX, total_CAN;
  89   bool crc_mode, at_eof, tx_ack;
  90 #ifdef USE_YMODEM_LENGTH
  91   unsigned long file_length, read_length;
  92 #endif
  93 } xyz;
  94
  95 #define xyzModem_CHAR_TIMEOUT            2000   /* 2 seconds */
  96 #define xyzModem_MAX_RETRIES             20
  97 #define xyzModem_MAX_RETRIES_WITH_CRC    10
  98 #define xyzModem_CAN_COUNT                3     /* Wait for 3 CAN before quitting */
  99
 100
 101 #ifndef REDBOOT                 /*SB */
 102 typedef int cyg_int32;
 103 int
 104 CYGACC_COMM_IF_GETC_TIMEOUT (char chan, char *c)
 105 {
 106 #define DELAY 20
 107   unsigned long counter = 0;
 108   while (!tstc () && (counter < xyzModem_CHAR_TIMEOUT * 1000 / DELAY))
 109     {
 110       udelay (DELAY);
 111       counter++;
 112     }
 113   if (tstc ())
 114     {
 115       *c = getc ();
 116       return 1;
 117     }
 118   return 0;
 119 }
 120
 121 void
 122 CYGACC_COMM_IF_PUTC (char x, char y)
 123 {
 124   putc (y);
 125 }
 126
 127 /* Validate a hex character */
 128 __inline__ static bool
 129 _is_hex (char c)
 130 {
 131   return (((c >= '0') && (c <= '9')) ||
 132           ((c >= 'A') && (c <= 'F')) || ((c >= 'a') && (c <= 'f')));
 133 }
 134
 135 /* Convert a single hex nibble */
 136 __inline__ static int
 137 _from_hex (char c)
 138 {
 139   int ret = 0;
 140
 141   if ((c >= '0') && (c <= '9'))
 142     {
 143       ret = (c - '0');
 144     }
 145   else if ((c >= 'a') && (c <= 'f'))
 146     {
 147       ret = (c - 'a' + 0x0a);
 148     }
 149   else if ((c >= 'A') && (c <= 'F'))
 150     {
 151       ret = (c - 'A' + 0x0A);
 152     }
 153   return ret;
 154 }
 155
 156 /* Convert a character to lower case */
 157 __inline__ static char
 158 _tolower (char c)
 159 {
 160   if ((c >= 'A') && (c <= 'Z'))
 161     {
 162       c = (c - 'A') + 'a';
 163     }
 164   return c;
 165 }
 166
 167 /* Parse (scan) a number */
 168 bool
 169 parse_num (char *s, unsigned long *val, char **es, char *delim)
 170 {
 171   bool first = true;
 172   int radix = 10;
 173   char c;
 174   unsigned long result = 0;
 175   int digit;
 176
 177   while (*s == ' ')
 178     s++;
 179   while (*s)
 180     {
 181       if (first && (s[0] == '0') && (_tolower (s[1]) == 'x'))
 182         {
 183           radix = 16;
 184           s += 2;
 185         }
 186       first = false;
 187       c = *s++;
 188       if (_is_hex (c) && ((digit = _from_hex (c)) < radix))
 189         {
 190           /* Valid digit */
 191 #ifdef CYGPKG_HAL_MIPS
 192           /* FIXME: tx49 compiler generates 0x2539018 for MUL which */
 193           /* isn't any good. */
 194           if (16 == radix)
 195             result = result << 4;
 196           else
 197             result = 10 * result;
 198           result += digit;
 199 #else
 200           result = (result * radix) + digit;
 201 #endif
 202         }
 203       else
 204         {
 205           if (delim != (char *) 0)
 206             {
 207               /* See if this character is one of the delimiters */
 208               char *dp = delim;
 209               while (*dp && (c != *dp))
 210                 dp++;
 211               if (*dp)
 212                 break;          /* Found a good delimiter */
 213             }
 214           return false;         /* Malformatted number */
 215         }
 216     }
 217   *val = result;
 218   if (es != (char **) 0)
 219     {
 220       *es = s;
 221     }
 222   return true;
 223 }
 224
 225 #endif
 226
 227 #define USE_SPRINTF
 228 #ifdef DEBUG
 229 #ifndef USE_SPRINTF
 230 /*
 231  * Note: this debug setup only works if the target platform has two serial ports
 232  * available so that the other one (currently only port 1) can be used for debug
 233  * messages.
 234  */
 235 static int
 236 zm_dprintf (char *fmt, ...)
 237 {
 238   int cur_console;
 239   va_list args;
 240
 241   va_start (args, fmt);
 242 #ifdef REDBOOT
 243   cur_console =
 244     CYGACC_CALL_IF_SET_CONSOLE_COMM
 245     (CYGNUM_CALL_IF_SET_COMM_ID_QUERY_CURRENT);
 246   CYGACC_CALL_IF_SET_CONSOLE_COMM (1);
 247 #endif
 248   diag_vprintf (fmt, args);
 249 #ifdef REDBOOT
 250   CYGACC_CALL_IF_SET_CONSOLE_COMM (cur_console);
 251 #endif
 252 }
 253
 254 static void
 255 zm_flush (void)
 256 {
 257 }
 258
 259 #else
 260 /*
 261  * Note: this debug setup works by storing the strings in a fixed buffer
 262  */
 263 #define FINAL
 264 #ifdef FINAL
 265 static char *zm_out = (char *) 0x00380000;
 266 static char *zm_out_start = (char *) 0x00380000;
 267 #else
 268 static char zm_buf[8192];
 269 static char *zm_out = zm_buf;
 270 static char *zm_out_start = zm_buf;
 271
 272 #endif
 273 static int
 274 zm_dprintf (char *fmt, ...)
 275 {
 276   int len;
 277   va_list args;
 278
 279   va_start (args, fmt);
 280   len = diag_vsprintf (zm_out, fmt, args);
 281   zm_out += len;
 282   return len;
 283 }
 284
 285 static void
 286 zm_flush (void)
 287 {
 288 #ifdef REDBOOT
 289   char *p = zm_out_start;
 290   while (*p)
 291     mon_write_char (*p++);
 292 #endif
 293   zm_out = zm_out_start;
 294 }
 295 #endif
 296
 297 static void
 298 zm_dump_buf (void *buf, int len)
 299 {
 300 #ifdef REDBOOT
 301   diag_vdump_buf_with_offset (zm_dprintf, buf, len, 0);
 302 #else
 303
 304 #endif
 305 }
 306
 307 static unsigned char zm_buf[2048];
 308 static unsigned char *zm_bp;
 309
 310 static void
 311 zm_new (void)
 312 {
 313   zm_bp = zm_buf;
 314 }
 315
 316 static void
 317 zm_save (unsigned char c)
 318 {
 319   *zm_bp++ = c;
 320 }
 321
 322 static void
 323 zm_dump (int line)
 324 {
 325   zm_dprintf ("Packet at line: %d\n", line);
 326   zm_dump_buf (zm_buf, zm_bp - zm_buf);
 327 }
 328
 329 #define ZM_DEBUG(x) x
 330 #else
 331 #define ZM_DEBUG(x)
 332 #endif
 333
 334 /* Wait for the line to go idle */
 335 static void
 336 xyzModem_flush (void)
 337 {
 338   int res;
 339   char c;
 340   while (true)
 341     {
 342       res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
 343       if (!res)
 344         return;
 345     }
 346 }
 347
 348 static int
 349 xyzModem_get_hdr (void)
 350 {
 351   char c;
 352   int res;
 353   bool hdr_found = false;
 354   int i, can_total, hdr_chars;
 355   unsigned short cksum;
 356
 357   ZM_DEBUG (zm_new ());
 358   /* Find the start of a header */
 359   can_total = 0;
 360   hdr_chars = 0;
 361
 362   if (xyz.tx_ack)
 363     {
 364       CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
 365       xyz.tx_ack = false;
 366     }
 367   while (!hdr_found)
 368     {
 369       res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
 370       ZM_DEBUG (zm_save (c));
 371       if (res)
 372         {
 373           hdr_chars++;
 374           switch (c)
 375             {
 376             case SOH:
 377               xyz.total_SOH++;
 378             case STX:
 379               if (c == STX)
 380                 xyz.total_STX++;
 381               hdr_found = true;
 382               break;
 383             case CAN:
 384               xyz.total_CAN++;
 385               ZM_DEBUG (zm_dump (__LINE__));
 386               if (++can_total == xyzModem_CAN_COUNT)
 387                 {
 388                   return xyzModem_cancel;
 389                 }
 390               else
 391                 {
 392                   /* Wait for multiple CAN to avoid early quits */
 393                   break;
 394                 }
 395             case EOT:
 396               /* EOT only supported if no noise */
 397               if (hdr_chars == 1)
 398                 {
 399                   CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
 400                   ZM_DEBUG (zm_dprintf ("ACK on EOT #%d\n", __LINE__));
 401                   ZM_DEBUG (zm_dump (__LINE__));
 402                   return xyzModem_eof;
 403                 }
 404             default:
 405               /* Ignore, waiting for start of header */
 406               ;
 407             }
 408         }
 409       else
 410         {
 411           /* Data stream timed out */
 412           xyzModem_flush ();    /* Toss any current input */
 413           ZM_DEBUG (zm_dump (__LINE__));
 414           CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000);
 415           return xyzModem_timeout;
 416         }
 417     }
 418
 419   /* Header found, now read the data */
 420   res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.blk);
 421   ZM_DEBUG (zm_save (xyz.blk));
 422   if (!res)
 423     {
 424       ZM_DEBUG (zm_dump (__LINE__));
 425       return xyzModem_timeout;
 426     }
 427   res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.cblk);
 428   ZM_DEBUG (zm_save (xyz.cblk));
 429   if (!res)
 430     {
 431       ZM_DEBUG (zm_dump (__LINE__));
 432       return xyzModem_timeout;
 433     }
 434   xyz.len = (c == SOH) ? 128 : 1024;
 435   xyz.bufp = xyz.pkt;
 436   for (i = 0; i < xyz.len; i++)
 437     {
 438       res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
 439       ZM_DEBUG (zm_save (c));
 440       if (res)
 441         {
 442           xyz.pkt[i] = c;
 443         }
 444       else
 445         {
 446           ZM_DEBUG (zm_dump (__LINE__));
 447           return xyzModem_timeout;
 448         }
 449     }
 450   res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc1);
 451   ZM_DEBUG (zm_save (xyz.crc1));
 452   if (!res)
 453     {
 454       ZM_DEBUG (zm_dump (__LINE__));
 455       return xyzModem_timeout;
 456     }
 457   if (xyz.crc_mode)
 458     {
 459       res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc2);
 460       ZM_DEBUG (zm_save (xyz.crc2));
 461       if (!res)
 462         {
 463           ZM_DEBUG (zm_dump (__LINE__));
 464           return xyzModem_timeout;
 465         }
 466     }
 467   ZM_DEBUG (zm_dump (__LINE__));
 468   /* Validate the message */
 469   if ((xyz.blk ^ xyz.cblk) != (unsigned char) 0xFF)
 470     {
 471       ZM_DEBUG (zm_dprintf
 472                 ("Framing error - blk: %x/%x/%x\n", xyz.blk, xyz.cblk,
 473                  (xyz.blk ^ xyz.cblk)));
 474       ZM_DEBUG (zm_dump_buf (xyz.pkt, xyz.len));
 475       xyzModem_flush ();
 476       return xyzModem_frame;
 477     }
 478   /* Verify checksum/CRC */
 479   if (xyz.crc_mode)
 480     {
 481       cksum = cyg_crc16 (xyz.pkt, xyz.len);
 482       if (cksum != ((xyz.crc1 << 8) | xyz.crc2))
 483         {
 484           ZM_DEBUG (zm_dprintf ("CRC error - recvd: %02x%02x, computed: %x\n",
 485                                 xyz.crc1, xyz.crc2, cksum & 0xFFFF));
 486           return xyzModem_cksum;
 487         }
 488     }
 489   else
 490     {
 491       cksum = 0;
 492       for (i = 0; i < xyz.len; i++)
 493         {
 494           cksum += xyz.pkt[i];
 495         }
 496       if (xyz.crc1 != (cksum & 0xFF))
 497         {
 498           ZM_DEBUG (zm_dprintf
 499                     ("Checksum error - recvd: %x, computed: %x\n", xyz.crc1,
 500                      cksum & 0xFF));
 501           return xyzModem_cksum;
 502         }
 503     }
 504   /* If we get here, the message passes [structural] muster */
 505   return 0;
 506 }
 507
 508 int
 509 xyzModem_stream_open (connection_info_t * info, int *err)
 510 {
 511 #ifdef REDBOOT
 512   int console_chan;
 513 #endif
 514   int stat = 0;
 515   int retries = xyzModem_MAX_RETRIES;
 516   int crc_retries = xyzModem_MAX_RETRIES_WITH_CRC;
 517
 518 /*    ZM_DEBUG(zm_out = zm_out_start); */
 519 #ifdef xyzModem_zmodem
 520   if (info->mode == xyzModem_zmodem)
 521     {
 522       *err = xyzModem_noZmodem;
 523       return -1;
 524     }
 525 #endif
 526
 527 #ifdef REDBOOT
 528   /* Set up the I/O channel.  Note: this allows for using a different port in the future */
 529   console_chan =
 530     CYGACC_CALL_IF_SET_CONSOLE_COMM
 531     (CYGNUM_CALL_IF_SET_COMM_ID_QUERY_CURRENT);
 532   if (info->chan >= 0)
 533     {
 534       CYGACC_CALL_IF_SET_CONSOLE_COMM (info->chan);
 535     }
 536   else
 537     {
 538       CYGACC_CALL_IF_SET_CONSOLE_COMM (console_chan);
 539     }
 540   xyz.__chan = CYGACC_CALL_IF_CONSOLE_PROCS ();
 541
 542   CYGACC_CALL_IF_SET_CONSOLE_COMM (console_chan);
 543   CYGACC_COMM_IF_CONTROL (*xyz.__chan, __COMMCTL_SET_TIMEOUT,
 544                           xyzModem_CHAR_TIMEOUT);
 545 #else
 546 /* TODO: CHECK ! */
 547   int dummy;
 548   xyz.__chan = &dummy;
 549 #endif
 550   xyz.len = 0;
 551   xyz.crc_mode = true;
 552   xyz.at_eof = false;
 553   xyz.tx_ack = false;
 554   xyz.mode = info->mode;
 555   xyz.total_retries = 0;
 556   xyz.total_SOH = 0;
 557   xyz.total_STX = 0;
 558   xyz.total_CAN = 0;
 559 #ifdef USE_YMODEM_LENGTH
 560   xyz.read_length = 0;
 561   xyz.file_length = 0;
 562 #endif
 563
 564   CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
 565
 566   if (xyz.mode == xyzModem_xmodem)
 567     {
 568       /* X-modem doesn't have an information header - exit here */
 569       xyz.next_blk = 1;
 570       return 0;
 571     }
 572
 573   while (retries-- > 0)
 574     {
 575       stat = xyzModem_get_hdr ();
 576       if (stat == 0)
 577         {
 578           /* Y-modem file information header */
 579           if (xyz.blk == 0)
 580             {
 581 #ifdef USE_YMODEM_LENGTH
 582               /* skip filename */
 583               while (*xyz.bufp++);
 584               /* get the length */
 585               parse_num ((char *) xyz.bufp, &xyz.file_length, NULL, " ");
 586 #endif
 587               /* The rest of the file name data block quietly discarded */
 588               xyz.tx_ack = true;
 589             }
 590           xyz.next_blk = 1;
 591           xyz.len = 0;
 592           return 0;
 593         }
 594       else if (stat == xyzModem_timeout)
 595         {
 596           if (--crc_retries <= 0)
 597             xyz.crc_mode = false;
 598           CYGACC_CALL_IF_DELAY_US (5 * 100000); /* Extra delay for startup */
 599           CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
 600           xyz.total_retries++;
 601           ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__));
 602         }
 603       if (stat == xyzModem_cancel)
 604         {
 605           break;
 606         }
 607     }
 608   *err = stat;
 609   ZM_DEBUG (zm_flush ());
 610   return -1;
 611 }
 612
 613 int
 614 xyzModem_stream_read (char *buf, int size, int *err)
 615 {
 616   int stat, total, len;
 617   int retries;
 618
 619   total = 0;
 620   stat = xyzModem_cancel;
 621   /* Try and get 'size' bytes into the buffer */
 622   while (!xyz.at_eof && (size > 0))
 623     {
 624       if (xyz.len == 0)
 625         {
 626           retries = xyzModem_MAX_RETRIES;
 627           while (retries-- > 0)
 628             {
 629               stat = xyzModem_get_hdr ();
 630               if (stat == 0)
 631                 {
 632                   if (xyz.blk == xyz.next_blk)
 633                     {
 634                       xyz.tx_ack = true;
 635                       ZM_DEBUG (zm_dprintf
 636                                 ("ACK block %d (%d)\n", xyz.blk, __LINE__));
 637                       xyz.next_blk = (xyz.next_blk + 1) & 0xFF;
 638
 639 #if defined(xyzModem_zmodem) || defined(USE_YMODEM_LENGTH)
 640                       if (xyz.mode == xyzModem_xmodem || xyz.file_length == 0)
 641                         {
 642 #else
 643                       if (1)
 644                         {
 645 #endif
 646                           /* Data blocks can be padded with ^Z (EOF) characters */
 647                           /* This code tries to detect and remove them */
 648                           if ((xyz.bufp[xyz.len - 1] == EOF) &&
 649                               (xyz.bufp[xyz.len - 2] == EOF) &&
 650                               (xyz.bufp[xyz.len - 3] == EOF))
 651                             {
 652                               while (xyz.len
 653                                      && (xyz.bufp[xyz.len - 1] == EOF))
 654                                 {
 655                                   xyz.len--;
 656                                 }
 657                             }
 658                         }
 659
 660 #ifdef USE_YMODEM_LENGTH
 661                       /*
 662                        * See if accumulated length exceeds that of the file.
 663                        * If so, reduce size (i.e., cut out pad bytes)
 664                        * Only do this for Y-modem (and Z-modem should it ever
 665                        * be supported since it can fall back to Y-modem mode).
 666                        */
 667                       if (xyz.mode != xyzModem_xmodem && 0 != xyz.file_length)
 668                         {
 669                           xyz.read_length += xyz.len;
 670                           if (xyz.read_length > xyz.file_length)
 671                             {
 672                               xyz.len -= (xyz.read_length - xyz.file_length);
 673                             }
 674                         }
 675 #endif
 676                       break;
 677                     }
 678                   else if (xyz.blk == ((xyz.next_blk - 1) & 0xFF))
 679                     {
 680                       /* Just re-ACK this so sender will get on with it */
 681                       CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
 682                       continue; /* Need new header */
 683                     }
 684                   else
 685                     {
 686                       stat = xyzModem_sequence;
 687                     }
 688                 }
 689               if (stat == xyzModem_cancel)
 690                 {
 691                   break;
 692                 }
 693               if (stat == xyzModem_eof)
 694                 {
 695                   CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
 696                   ZM_DEBUG (zm_dprintf ("ACK (%d)\n", __LINE__));
 697                   if (xyz.mode == xyzModem_ymodem)
 698                     {
 699                       CYGACC_COMM_IF_PUTC (*xyz.__chan,
 700                                            (xyz.crc_mode ? 'C' : NAK));
 701                       xyz.total_retries++;
 702                       ZM_DEBUG (zm_dprintf ("Reading Final Header\n"));
 703                       stat = xyzModem_get_hdr ();
 704                       CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
 705                       ZM_DEBUG (zm_dprintf ("FINAL ACK (%d)\n", __LINE__));
 706                     }
 707                   xyz.at_eof = true;
 708                   break;
 709                 }
 710               CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
 711               xyz.total_retries++;
 712               ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__));
 713             }
 714           if (stat < 0)
 715             {
 716               *err = stat;
 717               xyz.len = -1;
 718               return total;
 719             }
 720         }
 721       /* Don't "read" data from the EOF protocol package */
 722       if (!xyz.at_eof)
 723         {
 724           len = xyz.len;
 725           if (size < len)
 726             len = size;
 727           memcpy (buf, xyz.bufp, len);
 728           size -= len;
 729           buf += len;
 730           total += len;
 731           xyz.len -= len;
 732           xyz.bufp += len;
 733         }
 734     }
 735   return total;
 736 }
 737
 738 void
 739 xyzModem_stream_close (int *err)
 740 {
 741   diag_printf
 742     ("xyzModem - %s mode, %d(SOH)/%d(STX)/%d(CAN) packets, %d retries\n",
 743      xyz.crc_mode ? "CRC" : "Cksum", xyz.total_SOH, xyz.total_STX,
 744      xyz.total_CAN, xyz.total_retries);
 745   ZM_DEBUG (zm_flush ());
 746 }
 747
 748 /* Need to be able to clean out the input buffer, so have to take the */
 749 /* getc */
 750 void
 751 xyzModem_stream_terminate (bool abort, int (*getc) (void))
 752 {
 753   int c;
 754
 755   if (abort)
 756     {
 757       ZM_DEBUG (zm_dprintf ("!!!! TRANSFER ABORT !!!!\n"));
 758       switch (xyz.mode)
 759         {
 760         case xyzModem_xmodem:
 761         case xyzModem_ymodem:
 762           /* The X/YMODEM Spec seems to suggest that multiple CAN followed by an equal */
 763           /* number of Backspaces is a friendly way to get the other end to abort. */
 764           CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
 765           CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
 766           CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
 767           CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
 768           CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
 769           CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
 770           CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
 771           CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
 772           /* Now consume the rest of what's waiting on the line. */
 773           ZM_DEBUG (zm_dprintf ("Flushing serial line.\n"));
 774           xyzModem_flush ();
 775           xyz.at_eof = true;
 776           break;
 777 #ifdef xyzModem_zmodem
 778         case xyzModem_zmodem:
 779           /* Might support it some day I suppose. */
 780 #endif
 781           break;
 782         }
 783     }
 784   else
 785     {
 786       ZM_DEBUG (zm_dprintf ("Engaging cleanup mode...\n"));
 787       /*
 788        * Consume any trailing crap left in the inbuffer from
 789        * previous recieved blocks. Since very few files are an exact multiple
 790        * of the transfer block size, there will almost always be some gunk here.
 791        * If we don't eat it now, RedBoot will think the user typed it.
 792        */
 793       ZM_DEBUG (zm_dprintf ("Trailing gunk:\n"));
 794       while ((c = (*getc) ()) > -1);
 795       ZM_DEBUG (zm_dprintf ("\n"));
 796       /*
 797        * Make a small delay to give terminal programs like minicom
 798        * time to get control again after their file transfer program
 799        * exits.
 800        */
 801       CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000);
 802     }
 803 }
 804
 805 char *
 806 xyzModem_error (int err)
 807 {
 808   switch (err)
 809     {
 810     case xyzModem_access:
 811       return "Can't access file";
 812       break;
 813     case xyzModem_noZmodem:
 814       return "Sorry, zModem not available yet";
 815       break;
 816     case xyzModem_timeout:
 817       return "Timed out";
 818       break;
 819     case xyzModem_eof:
 820       return "End of file";
 821       break;
 822     case xyzModem_cancel:
 823       return "Cancelled";
 824       break;
 825     case xyzModem_frame:
 826       return "Invalid framing";
 827       break;
 828     case xyzModem_cksum:
 829       return "CRC/checksum error";
 830       break;
 831     case xyzModem_sequence:
 832       return "Block sequence error";
 833       break;
 834     default:
 835       return "Unknown error";
 836       break;
 837     }
 838 }
 839
 840 /*
 841  * RedBoot interface
 842  */
 843 #if 0                           /* SB */
 844 GETC_IO_FUNCS (xyzModem_io, xyzModem_stream_open, xyzModem_stream_close,
 845                xyzModem_stream_terminate, xyzModem_stream_read,
 846                xyzModem_error);
 847 RedBoot_load (xmodem, xyzModem_io, false, false, xyzModem_xmodem);
 848 RedBoot_load (ymodem, xyzModem_io, false, false, xyzModem_ymodem);
 849 #endif