| 1 | /* XMODEM support for GDB, the GNU debugger. |
| 2 | Copyright 1995, 2000, 2001 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program 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., 59 Temple Place - Suite 330, |
| 19 | Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "serial.h" |
| 23 | #include "target.h" |
| 24 | #include "xmodem.h" |
| 25 | |
| 26 | /* These definitions are for xmodem protocol. */ |
| 27 | |
| 28 | #define SOH 0x01 |
| 29 | #define STX 0x02 |
| 30 | #define ACK 0x06 |
| 31 | #define NAK 0x15 |
| 32 | #define EOT 0x04 |
| 33 | #define CANCEL 0x18 |
| 34 | |
| 35 | static int blknum; /* XMODEM block number */ |
| 36 | static int crcflag; /* Sez we are using CRC's instead of cksums */ |
| 37 | |
| 38 | static int |
| 39 | readchar (serial_t desc, int timeout) |
| 40 | { |
| 41 | int c; |
| 42 | |
| 43 | c = SERIAL_READCHAR (desc, timeout); |
| 44 | |
| 45 | if (remote_debug > 0) |
| 46 | fputc_unfiltered (c, gdb_stdlog); |
| 47 | |
| 48 | if (c >= 0) |
| 49 | return c; |
| 50 | |
| 51 | if (c == SERIAL_TIMEOUT) |
| 52 | error ("Timeout reading from remote system."); |
| 53 | |
| 54 | perror_with_name ("xmodem.c:readchar()"); |
| 55 | } |
| 56 | |
| 57 | #define CRC16 0x1021 /* Generator polynomial (X^16 + X^12 + X^5 + 1) */ |
| 58 | |
| 59 | static unsigned short *crctab; |
| 60 | |
| 61 | /* Call this to init the fast CRC-16 calculation table. */ |
| 62 | |
| 63 | static void |
| 64 | crcinit (void) |
| 65 | { |
| 66 | static int crctab_inited = 0; |
| 67 | int val; |
| 68 | |
| 69 | if (crctab_inited == 1) |
| 70 | return; |
| 71 | |
| 72 | crctab = xmalloc (256 * sizeof (short)); |
| 73 | |
| 74 | for (val = 0; val <= 255; val++) |
| 75 | { |
| 76 | int i; |
| 77 | unsigned int crc; |
| 78 | |
| 79 | crc = val << 8; |
| 80 | |
| 81 | for (i = 0; i < 8; ++i) |
| 82 | { |
| 83 | crc <<= 1; |
| 84 | |
| 85 | if (crc & 0x10000) |
| 86 | crc ^= CRC16; |
| 87 | } |
| 88 | |
| 89 | crctab[val] = crc; |
| 90 | } |
| 91 | |
| 92 | crctab_inited = 1; |
| 93 | } |
| 94 | |
| 95 | /* Calculate a CRC-16 for the LEN byte message pointed at by P. */ |
| 96 | |
| 97 | static unsigned short |
| 98 | docrc (unsigned char *p, int len) |
| 99 | { |
| 100 | unsigned short crc = 0; |
| 101 | |
| 102 | while (len-- > 0) |
| 103 | crc = (crc << 8) ^ crctab[(crc >> 8) ^ *p++]; |
| 104 | |
| 105 | return crc; |
| 106 | } |
| 107 | |
| 108 | /* Start up the transmit process. Reset state variables. Wait for receiver to |
| 109 | send NAK or CRC request. */ |
| 110 | |
| 111 | int |
| 112 | xmodem_init_xfer (serial_t desc) |
| 113 | { |
| 114 | int c; |
| 115 | int i; |
| 116 | |
| 117 | blknum = 1; |
| 118 | crcflag = 0; |
| 119 | crcinit (); |
| 120 | |
| 121 | for (i = 1; i <= 10; i++) |
| 122 | { |
| 123 | c = readchar (desc, 6); |
| 124 | |
| 125 | switch (c) |
| 126 | { |
| 127 | case 'C': |
| 128 | crcflag = 1; |
| 129 | case NAK: |
| 130 | return 0; |
| 131 | default: |
| 132 | fprintf_unfiltered (gdb_stderr, "xmodem_init_xfer: Got unexpected character %c (0%o)\n", c, c); |
| 133 | continue; |
| 134 | case CANCEL: /* target aborted load */ |
| 135 | fprintf_unfiltered (gdb_stderr, "Got a CANCEL from the target.\n"); |
| 136 | continue; |
| 137 | } |
| 138 | } |
| 139 | error ("xmodem_init_xfer: Too many unexpected characters."); |
| 140 | } |
| 141 | |
| 142 | /* Take 128 bytes of data and make a packet out of it. |
| 143 | |
| 144 | * Each packet looks like this: |
| 145 | * +-----+-------+-------+------+-----+ |
| 146 | * | SOH | Seq1. | Seq2. | data | SUM | |
| 147 | * +-----+-------+-------+------+-----+ |
| 148 | * SOH = 0x01 |
| 149 | * Seq1 = The sequence number. |
| 150 | * Seq2 = The complement of the sequence number. |
| 151 | * Data = A 128 bytes of data. |
| 152 | * SUM = Add the contents of the 128 bytes and use the low-order |
| 153 | * 8 bits of the result. |
| 154 | * |
| 155 | * send_xmodem_packet fills in the XMODEM fields of PACKET and sends it to the |
| 156 | * remote system. PACKET must be XMODEM_PACKETSIZE bytes long. The data must |
| 157 | * start 3 bytes after the beginning of the packet to leave room for the |
| 158 | * XMODEM header. LEN is the length of the data portion of the packet (and |
| 159 | * must be <= 128 bytes). If it is < 128 bytes, ^Z padding will be added. |
| 160 | */ |
| 161 | |
| 162 | void |
| 163 | xmodem_send_packet (serial_t desc, unsigned char *packet, int len, int hashmark) |
| 164 | { |
| 165 | int i; |
| 166 | int retries; |
| 167 | int pktlen; |
| 168 | int datasize; |
| 169 | |
| 170 | /* build the packet header */ |
| 171 | |
| 172 | packet[1] = blknum; |
| 173 | packet[2] = ~blknum; |
| 174 | |
| 175 | blknum++; |
| 176 | |
| 177 | if (len <= XMODEM_DATASIZE) |
| 178 | { |
| 179 | packet[0] = SOH; |
| 180 | datasize = XMODEM_DATASIZE; |
| 181 | } |
| 182 | else if (len <= XMODEM_1KDATASIZE) |
| 183 | { |
| 184 | packet[0] = STX; |
| 185 | datasize = XMODEM_1KDATASIZE; |
| 186 | } |
| 187 | else |
| 188 | internal_error (__FILE__, __LINE__, "failed internal consistency check"); /* Packet way too large */ |
| 189 | |
| 190 | /* Add ^Z padding if packet < 128 (or 1024) bytes */ |
| 191 | |
| 192 | memset (packet + 3 + len, '\026', datasize - len); |
| 193 | |
| 194 | if (crcflag) |
| 195 | { |
| 196 | int crc; |
| 197 | |
| 198 | crc = docrc (packet + 3, datasize); |
| 199 | |
| 200 | packet[3 + datasize] = crc >> 8; |
| 201 | packet[3 + datasize + 1] = crc; |
| 202 | pktlen = datasize + 5; |
| 203 | } |
| 204 | else |
| 205 | { |
| 206 | int sum; |
| 207 | |
| 208 | sum = 0; |
| 209 | for (i = 3; i < datasize + 3; i++) |
| 210 | sum += packet[i]; |
| 211 | |
| 212 | packet[3 + datasize] = sum; /* add the checksum */ |
| 213 | pktlen = datasize + 4; |
| 214 | } |
| 215 | |
| 216 | for (retries = 3; retries >= 0; retries--) |
| 217 | { |
| 218 | int c; |
| 219 | |
| 220 | SERIAL_WRITE (desc, packet, pktlen); |
| 221 | |
| 222 | c = readchar (desc, 3); |
| 223 | switch (c) |
| 224 | { |
| 225 | case ACK: |
| 226 | return; |
| 227 | case NAK: |
| 228 | if (!hashmark) |
| 229 | continue; |
| 230 | putchar_unfiltered ('-'); |
| 231 | gdb_flush (gdb_stdout); |
| 232 | continue; |
| 233 | case CANCEL: |
| 234 | error ("xmodem_send_packet: Transfer aborted by receiver."); |
| 235 | default: |
| 236 | fprintf_unfiltered (gdb_stderr, "xmodem_send_packet: Got unexpected character %c (0%o)\n", c, c); |
| 237 | continue; |
| 238 | } |
| 239 | } |
| 240 | |
| 241 | SERIAL_WRITE (desc, "\004", 1); /* Send an EOT */ |
| 242 | |
| 243 | error ("xmodem_send_packet: Excessive retries."); |
| 244 | } |
| 245 | |
| 246 | /* Finish off the transfer. Send out the EOT, and wait for an ACK. */ |
| 247 | |
| 248 | void |
| 249 | xmodem_finish_xfer (serial_t desc) |
| 250 | { |
| 251 | int retries; |
| 252 | |
| 253 | for (retries = 10; retries >= 0; retries--) |
| 254 | { |
| 255 | int c; |
| 256 | |
| 257 | SERIAL_WRITE (desc, "\004", 1); /* Send an EOT */ |
| 258 | |
| 259 | c = readchar (desc, 3); |
| 260 | switch (c) |
| 261 | { |
| 262 | case ACK: |
| 263 | return; |
| 264 | case NAK: |
| 265 | continue; |
| 266 | case CANCEL: |
| 267 | error ("xmodem_finish_xfer: Transfer aborted by receiver."); |
| 268 | default: |
| 269 | fprintf_unfiltered (gdb_stderr, "xmodem_send_packet: Got unexpected character %c (0%o)\n", c, c); |
| 270 | continue; |
| 271 | } |
| 272 | } |
| 273 | |
| 274 | error ("xmodem_finish_xfer: Excessive retries."); |
| 275 | } |