aboutsummaryrefslogtreecommitdiffstats
path: root/com32/sysdump/be_ymodem.c
blob: 632758d9a267a612ea867764fbc5e03bb9b787e4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
/*
 * Ymodem send routine.  Only supports 1K blocks and CRC mode.
 */

#include <string.h>
#include <stdio.h>
#include <inttypes.h>
#include "backend.h"
#include "serial.h"

enum {
    SOH = 0x01,
    STX = 0x02,
    EOT = 0x04,
    ACK = 0x06,
    NAK = 0x15,
    CAN = 0x18,
};

/*
 * Append a CRC16 to a block
 */
static void add_crc16(uint8_t * blk, int len)
{
    static const uint16_t crctab[256] = {
	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
	0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
	0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
	0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
	0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
	0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
	0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
	0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
	0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
	0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
	0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
	0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
	0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
    };
    uint16_t crc = 0;

    while (len--)
	crc = crctab[(crc >> 8) ^ *blk++] ^ crc << 8;

    *blk++ = crc >> 8;
    *blk = crc;
}

static void send_ack(struct backend *be, const uint8_t *blk, size_t bytes);

static void send_ack_blk(struct backend *be, uint8_t *blk)
{
    printf("Sending block %u...\r", be->ymodem.seq);

    blk[0] = STX;
    blk[1] = be->ymodem.seq++;
    blk[2] = ~blk[1];
    add_crc16(blk+3, 1024);

    send_ack(be, blk, 1024+5);
}

static void send_ack(struct backend *be, const uint8_t *blk, size_t bytes)
{
    uint8_t ack_buf;

    serial_write(&be->ymodem.serial, blk, bytes);

    do {
	do {
	    serial_read(&be->ymodem.serial, &ack_buf, 1);
	} while (ack_buf != ACK && ack_buf != NAK);
    } while (ack_buf == NAK);
}

static int be_ymodem_open(struct backend *be, const char *argv[], size_t len)
{
    uint8_t ack_buf, blk_buf[1024 + 5];

    be->ymodem.seq = 0;

    /* Initialize serial port */
    if (serial_init(&be->ymodem.serial, argv+1))
	return -1;
    
    /* Wait for initial handshake */
    printf("Waiting for handshake...\n");
    do {
	serial_read(&be->ymodem.serial, &ack_buf, 1);
    } while (ack_buf != 'C');

    snprintf((char *)blk_buf+3, 1024, "%s%c%zu", argv[0], 0, len);
    send_ack_blk(be, blk_buf);

    return 0;
}

static int be_ymodem_write(struct backend *be, const char *buf, size_t len)
{
    static const uint8_t eot_buf = EOT;
    uint8_t ack_buf;
    uint8_t blk_buf[1024 + 5];
    
    memcpy(blk_buf+3, buf, len);
    if (len < 1024)
	memset(blk_buf+3+1024-len, 0x1a, 1024-len);

    send_ack_blk(be, blk_buf);

    if (len < 1024) {
	printf("\nSending EOT...\n");
	send_ack(be, &eot_buf, 1);

	printf("Waiting for handshake...\n");
	do {
	    serial_read(&be->ymodem.serial, &ack_buf, 1);
	} while (ack_buf != 'C');
	be->ymodem.seq = 0;
	
	printf("Sending batch termination block...\n");
	memset(blk_buf+3, 0, 128);
	blk_buf[0] = SOH;
	blk_buf[1] = 0;
	blk_buf[2] = 0xff;
	add_crc16(blk_buf + 3, 128);
	serial_write(&be->ymodem.serial, blk_buf, 128 + 5);
	/*
	 * rb doesn't seem to ack the EOT for an end batch transfer,
	 * contrary to spec.
	 */
	printf("Done.\n");
	serial_cleanup(&be->ymodem.serial);
    }

    return 0;
}	

struct backend be_ymodem = {
    .name       = "ymodem",
    .helpmsg    = "filename port [speed]",
    .minargs    = 2,
    .blocksize  = 1024,
	.flags  = BE_NEEDLEN,
    .open       = be_ymodem_open,
    .write      = be_ymodem_write,
};