// SPDX-License-Identifier: eCos-2.0
/*
*==========================================================================
*
* xyzModem.c
*
* RedBoot stream handler for xyzModem protocol
*
*==========================================================================
*#####DESCRIPTIONBEGIN####
*
* Author(s): gthomas
* Contributors: gthomas, tsmith, Yoshinori Sato
* Date: 2000-07-14
* Purpose:
* Description:
*
* This code is part of RedBoot (tm).
*
*####DESCRIPTIONEND####
*
*==========================================================================
*/
#include <common.h>
#include <xyzModem.h>
#include <stdarg.h>
#include <crc.h>
/* Assumption - run xyzModem protocol over the console port */
/* Values magic to the protocol */
#define SOH 0x01
#define STX 0x02
#define EOT 0x04
#define ACK 0x06
#define BSP 0x08
#define NAK 0x15
#define CAN 0x18
#define EOF 0x1A /* ^Z for DOS officionados */
/* Data & state local to the protocol */
static struct
{
int *__chan;
unsigned char pkt[1024], *bufp;
unsigned char blk, cblk, crc1, crc2;
unsigned char next_blk; /* Expected block */
int len, mode, total_retries;
int total_SOH, total_STX, total_CAN;
bool crc_mode, at_eof, tx_ack;
unsigned long file_length, read_length;
} xyz;
#define xyzModem_CHAR_TIMEOUT 2000 /* 2 seconds */
#define xyzModem_MAX_RETRIES 20
#define xyzModem_MAX_RETRIES_WITH_CRC 10
#define xyzModem_CAN_COUNT 3 /* Wait for 3 CAN before quitting */
typedef int cyg_int32;
static int
CYGACC_COMM_IF_GETC_TIMEOUT (char chan, char *c)
{
ulong now = get_timer(0);
while (!tstc ())
{
if (get_timer(now) > xyzModem_CHAR_TIMEOUT)
break;
}
if (tstc ())
{
*c = getc ();
return 1;
}
return 0;
}
static void
CYGACC_COMM_IF_PUTC (char x, char y)
{
putc (y);
}
/* Validate a hex character */
__inline__ static bool
_is_hex (char c)
{
return (((c >= '0') && (c <= '9')) ||
((c >= 'A') && (c <= 'F')) || ((c >= 'a') && (c <= 'f')));
}
/* Convert a single hex nibble */
__inline__ static int
_from_hex (char c)
{
int ret = 0;
if ((c >= '0') && (c <= '9'))
{
ret = (c - '0');
}
else if ((c >= 'a') && (c <= 'f'))
{
ret = (c - 'a' + 0x0a);
}
else if ((c >= 'A') && (c <= 'F'))
{
ret = (c - 'A' + 0x0A);
}
return ret;
}
/* Convert a character to lower case */
__inline__ static char
_tolower (char c)
{
if ((c >= 'A') && (c <= 'Z'))
{
c = (c - 'A') + 'a';
}
return c;
}
/* Parse (scan) a number */
static bool
parse_num (char *s, unsigned long *val, char **es, char *delim)
{
bool first = true;
int radix = 10;
char c;
unsigned long result = 0;
int digit;
while (*s == ' ')
s++;
while (*s)
{
if (first && (s[0] == '0') && (_tolower (s[1]) == 'x'))
{
radix = 16;
s += 2;
}
first = false;
c = *s++;
if (_is_hex (c) && ((digit = _from_hex (c)) < radix))
{
/* Valid digit */
result = (result * radix) + digit;
}
else
{
if (delim != (char *) 0)
{
/* See if this character is one of the delimiters */
char *dp = delim;
while (*dp && (c != *dp))
dp++;
if (*dp)
break; /* Found a good delimiter */
}
return false; /* Malformatted number */
}
}
*val = result;
if (es != (char **) 0)
{
*es = s;
}
return true;
}
#if defined(DEBUG) && !defined(CONFIG_USE_TINY_PRINTF)
/*
* Note: this debug setup works by storing the strings in a fixed buffer
*/
static char zm_debug_buf[8192];
static char *zm_out = zm_debug_buf;
static char *zm_out_start = zm_debug_buf;
static int
zm_dprintf(char *fmt, ...)
{
int len;
va_list args;
va_start(args, fmt);
len = diag_vsprintf(zm_out, fmt, args);
va_end(args);
zm_out += len;
return len;
}
static void
zm_flush (void)
{
zm_out = zm_out_start;
}
static void
zm_dump_buf (void *buf, int len)
{
}
static unsigned char zm_buf[2048];
static unsigned char *zm_bp;
static void
zm_new (void)
{
zm_bp = zm_buf;
}
static void
zm_save (unsigned char c)
{
*zm_bp++ = c;
}
static void
zm_dump (int line)
{
zm_dprintf ("Packet at line: %d\n", line);
zm_dump_buf (zm_buf, zm_bp - zm_buf);
}
#define ZM_DEBUG(x) x
#else
#define ZM_DEBUG(x)
#endif
/* Wait for the line to go idle */
static void
xyzModem_flush (void)
{
int res;
char c;
while (true)
{
res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
if (!res)
return;
}
}
static int
xyzModem_get_hdr (void)
{
char c;
int res;
bool hdr_found = false;
int i, can_total, hdr_chars;
unsigned short cksum;
ZM_DEBUG (zm_new ());
/* Find the start of a header */
can_total = 0;
hdr_chars = 0;
if (xyz.tx_ack)
{
CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
xyz.tx_ack = false;
}
while (!hdr_found)
{
res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
ZM_DEBUG (zm_save (c));
if (res)
{
hdr_chars++;
switch (c)
{
case SOH:
xyz.total_SOH++;
case STX:
if (c == STX)
xyz.total_STX++;
hdr_found = true;
break;
case CAN:
xyz.total_CAN++;
ZM_DEBUG (zm_dump (__LINE__));
if (++can_total == xyzModem_CAN_COUNT)
{
return xyzModem_cancel;
}
else
{
/* Wait for multiple CAN to avoid early quits */
break;
}
case EOT:
/* EOT only supported if no noise */
if (hdr_chars == 1)
{
CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
ZM_DEBUG (zm_dprintf ("ACK on EOT #%d\n", __LINE__));
ZM_DEBUG (zm_dump (__LINE__));
return xyzModem_eof;
}
default:
/* Ignore, waiting for start of header */
;
}
}
else
{
/* Data stream timed out */
xyzModem_flush (); /* Toss any current input */
ZM_DEBUG (zm_dump (__LINE__));
CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000);
return xyzModem_timeout;
}
}
/* Header found, now read the data */
res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.blk);
ZM_DEBUG (zm_save (xyz.blk));
if (!res)
{
ZM_DEBUG (zm_dump (__LINE__));
return xyzModem_timeout;
}
res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.cblk);
ZM_DEBUG (zm_save (xyz.cblk));
if (!res)
{
ZM_DEBUG (zm_dump (__LINE__));
return xyzModem_timeout;
}
xyz.len = (c == SOH) ? 128 : 1024;
xyz.bufp = xyz.pkt;
for (i = 0; i < xyz.len; i++)
{
res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
ZM_DEBUG (zm_save (c));
if (res)
{
xyz.pkt[i] = c;
}
else
{
ZM_DEBUG (zm_dump (__LINE__));
return xyzModem_timeout;
}
}
res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc1);
ZM_DEBUG (zm_save (xyz.crc1));
if (!res)
{
ZM_DEBUG (zm_dump (__LINE__));
return xyzModem_timeout;
}
if (xyz.crc_mode)
{
res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc2);
ZM_DEBUG (zm_save (xyz.crc2));
if (!res)
{
ZM_DEBUG (zm_dump (__LINE__));
return xyzModem_timeout;
}
}
ZM_DEBUG (zm_dump (__LINE__));
/* Validate the message */
if ((xyz.blk ^ xyz.cblk) != (unsigned char) 0xFF)
{
ZM_DEBUG (zm_dprintf
("Framing error - blk: %x/%x/%x\n", xyz.blk, xyz.cblk,
(xyz.blk ^ xyz.cblk)));
ZM_DEBUG (zm_dump_buf (xyz.pkt, xyz.len));
xyzModem_flush ();
return xyzModem_frame;
}
/* Verify checksum/CRC */
if (xyz.crc_mode)
{
cksum = crc16_ccitt(0, xyz.pkt, xyz.len);
if (cksum != ((xyz.crc1 << 8) | xyz.crc2))
{
ZM_DEBUG (zm_dprintf ("CRC error - recvd: %02x%02x, computed: %x\n",
xyz.crc1, xyz.crc2, cksum & 0xFFFF));
return xyzModem_cksum;
}
}
else
{
cksum = 0;
for (i = 0; i < xyz.len; i++)
{
cksum += xyz.pkt[i];
}
if (xyz.crc1 != (cksum & 0xFF))
{
ZM_DEBUG (zm_dprintf
("Checksum error - recvd: %x, computed: %x\n", xyz.crc1,
cksum & 0xFF));
return xyzModem_cksum;
}
}
/* If we get here, the message passes [structural] muster */
return 0;
}
int
xyzModem_stream_open (connection_info_t * info, int *err)
{
int stat = 0;
int retries = xyzModem_MAX_RETRIES;
int crc_retries = xyzModem_MAX_RETRIES_WITH_CRC;
/* ZM_DEBUG(zm_out = zm_out_start); */
#ifdef xyzModem_zmodem
if (info->mode == xyzModem_zmodem)
{
*err = xyzModem_noZmodem;
return -1;
}
#endif
/* TODO: CHECK ! */
int dummy = 0;
xyz.__chan = &dummy;
xyz.len = 0;
xyz.crc_mode = true;
xyz.at_eof = false;
xyz.tx_ack = false;
xyz.mode = info->mode;
xyz.total_retries = 0;
xyz.total_SOH = 0;
xyz.total_STX = 0;
xyz.total_CAN = 0;
xyz.read_length = 0;
xyz.file_length = 0;
CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
if (xyz.mode == xyzModem_xmodem)
{
/* X-modem doesn't have an information header - exit here */
xyz.next_blk = 1;
return 0;
}
while (retries-- > 0)
{
stat = xyzModem_get_hdr ();
if (stat == 0)
{
/* Y-modem file information header */
if (xyz.blk == 0)
{
/* skip filename */
while (*xyz.bufp++);
/* get the length */
parse_num ((char *) xyz.bufp, &xyz.file_length, NULL, " ");
/* The rest of the file name data block quietly discarded */
xyz.tx_ack = true;
}
xyz.next_blk = 1;
xyz.len = 0;
return 0;
}
else if (stat == xyzModem_timeout)
{
if (--crc_retries <= 0)
xyz.crc_mode = false;
CYGACC_CALL_IF_DELAY_US (5 * 100000); /* Extra delay for startup */
CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
xyz.total_retries++;
ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__));
}
if (stat == xyzModem_cancel)
{
break;
}
}
*err = stat;
ZM_DEBUG (zm_flush ());
return -1;
}
int
xyzModem_stream_read (char *buf, int size, int *err)
{
int stat, total, len;
int retries;
total = 0;
stat = xyzModem_cancel;
/* Try and get 'size' bytes into the buffer */
while (!xyz.at_eof && (size > 0))
{
if (xyz.len == 0)
{
retries = xyzModem_MAX_RETRIES;
while (retries-- > 0)
{
stat = xyzModem_get_hdr ();
if (stat == 0)
{
if (xyz.blk == xyz.next_blk)
{
xyz.tx_ack = true;
ZM_DEBUG (zm_dprintf
("ACK block %d (%d)\n", xyz.blk, __LINE__));
xyz.next_blk = (xyz.next_blk + 1) & 0xFF;
if (xyz.mode == xyzModem_xmodem || xyz.file_length == 0)
{
/* Data blocks can be padded with ^Z (EOF) characters */
/* This code tries to detect and remove them */
if ((xyz.bufp[xyz.len - 1] == EOF) &&
(xyz.bufp[xyz.len - 2] == EOF) &&
(xyz.bufp[xyz.len - 3] == EOF))
{
while (xyz.len
&& (xyz.bufp[xyz.len - 1] == EOF))
{
xyz.len--;
}
}
}
/*
* See if accumulated length exceeds that of the file.
* If so, reduce size (i.e., cut out pad bytes)
* Only do this for Y-modem (and Z-modem should it ever
* be supported since it can fall back to Y-modem mode).
*/
if (xyz.mode != xyzModem_xmodem && 0 != xyz.file_length)
{
xyz.read_length += xyz.len;
if (xyz.read_length > xyz.file_length)
{
xyz.len -= (xyz.read_length - xyz.file_length);
}
}
break;
}
else if (xyz.blk == ((xyz.next_blk - 1) & 0xFF))
{
/* Just re-ACK this so sender will get on with it */
CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
continue; /* Need new header */
}
else
{
stat = xyzModem_sequence;
}
}
if (stat == xyzModem_cancel)
{
break;
}
if (stat == xyzModem_eof)
{
CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
ZM_DEBUG (zm_dprintf ("ACK (%d)\n", __LINE__));
if (xyz.mode == xyzModem_ymodem)
{
CYGACC_COMM_IF_PUTC (*xyz.__chan,
(xyz.crc_mode ? 'C' : NAK));
xyz.total_retries++;
ZM_DEBUG (zm_dprintf ("Reading Final Header\n"));
stat = xyzModem_get_hdr ();
CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
ZM_DEBUG (zm_dprintf ("FINAL ACK (%d)\n", __LINE__));
}
xyz.at_eof = true;
break;
}
CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
xyz.total_retries++;
ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__));
}
if (stat < 0)
{
*err = stat;
xyz.len = -1;
return total;
}
}
/* Don't "read" data from the EOF protocol package */
if (!xyz.at_eof)
{
len = xyz.len;
if (size < len)
len = size;
memcpy (buf, xyz.bufp, len);
size -= len;
buf += len;
total += len;
xyz.len -= len;
xyz.bufp += len;
}
}
return total;
}
void
xyzModem_stream_close (int *err)
{
diag_printf
("xyzModem - %s mode, %d(SOH)/%d(STX)/%d(CAN) packets, %d retries\n",
xyz.crc_mode ? "CRC" : "Cksum", xyz.total_SOH, xyz.total_STX,
xyz.total_CAN, xyz.total_retries);
ZM_DEBUG (zm_flush ());
}
/* Need to be able to clean out the input buffer, so have to take the */
/* getc */
void
xyzModem_stream_terminate (bool abort, int (*getc) (void))
{
int c;
if (abort)
{
ZM_DEBUG (zm_dprintf ("!!!! TRANSFER ABORT !!!!\n"));
switch (xyz.mode)
{
case xyzModem_xmodem:
case xyzModem_ymodem:
/* The X/YMODEM Spec seems to suggest that multiple CAN followed by an equal */
/* number of Backspaces is a friendly way to get the other end to abort. */
CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
/* Now consume the rest of what's waiting on the line. */
ZM_DEBUG (zm_dprintf ("Flushing serial line.\n"));
xyzModem_flush ();
xyz.at_eof = true;
break;
#ifdef xyzModem_zmodem
case xyzModem_zmodem:
/* Might support it some day I suppose. */
#endif
break;
}
}
else
{
ZM_DEBUG (zm_dprintf ("Engaging cleanup mode...\n"));
/*
* Consume any trailing crap left in the inbuffer from
* previous received blocks. Since very few files are an exact multiple
* of the transfer block size, there will almost always be some gunk here.
* If we don't eat it now, RedBoot will think the user typed it.
*/
ZM_DEBUG (zm_dprintf ("Trailing gunk:\n"));
while ((c = (*getc) ()) > -1)
;
ZM_DEBUG (zm_dprintf ("\n"));
/*
* Make a small delay to give terminal programs like minicom
* time to get control again after their file transfer program
* exits.
*/
CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000);
}
}
char *
xyzModem_error (int err)
{
switch (err)
{
case xyzModem_access:
return "Can't access file";
break;
case xyzModem_noZmodem:
return "Sorry, zModem not available yet";
break;
case xyzModem_timeout:
return "Timed out";
break;
case xyzModem_eof:
return "End of file";
break;
case xyzModem_cancel:
return "Cancelled";
break;
case xyzModem_frame:
return "Invalid framing";
break;
case xyzModem_cksum:
return "CRC/checksum error";
break;
case xyzModem_sequence:
return "Block sequence error";
break;
default:
return "Unknown error";
break;
}
}
/*
* RedBoot interface
*/