/**
* There is data available on the feed. Read it into the buffer
* then deal with what we got.
*
* @param ifd [in] File-descriptor of the input data-feed
* @retval 0 Success
* @retval ENOMEM Out of memory
* @retval ENODATA End of input data-feed
*/
int
feedTheXbuf(const int ifd)
{
int status;
size_t nn = 0;
/* space available in buffer */
ptrdiff_t remaining = (ptrdiff_t)theBuf->bufsiz - (theBuf->get - theBuf->base);
if (remaining <= CHUNKSIZE) {
if (theBuf->bufsiz >= maxProductSize) {
log_warning_q(
"Data-product would exceed %lu bytes. Resetting input buffer.",
maxProductSize);
justify_xbuf(theBuf, 0);
}
log_info_q("Expanding input buffer size to %lu\n",
(unsigned long)(2 * theBuf->bufsiz));
theBuf = expand_xbuf(theBuf, theBuf->bufsiz);
if (theBuf == NULL) {
status = errno == 0 ? ENOMEM : errno;
log_add_syserr("expand_xbuf");
log_flush_error();
return status;
}
}
status = (*read_feed)(ifd, (char *)theBuf->put, CHUNKSIZE, &nn);
if(status != ENOERR)
{
log_add_errno(status, "read_feed");
log_flush_error();
return status;
}
/* else */
if(nn == 0)
return ENODATA; /* end of file */
/* else */
/* usual case */
/* assert(nn > 0); */
theBuf->cnt += nn;
theBuf->put += nn;
return ENOERR;
}
int
scan_faa604 (xbuf * buf)
{
extern char *parity;
int sent = 0;
int ch;
static enum state
{
SKIP,
SEARCH,
HEADER_SEEN
}
state = SEARCH;
while ((ch = nextc (buf)) != EOB)
{
switch(ch) {
case SOH:
switch (state) {
case SKIP:
log_debug("Resync skipped %05ld bytes",
(long) (buf->get - buf->base) - 1);
break;
case HEADER_SEEN:
sohetx_missed++;
log_error("Lone SOH error - %s",
faa604_err_ident(buf));
break;
}
justify_xbuf (buf, 1);
state = HEADER_SEEN;
break;
case ETX:
switch (state) {
case SKIP:
#if 0
case SEARCH:
#endif
sohetx_missed++;
log_error("Lone ETX error - %s",
faa604_err_ident(buf));
break;
case HEADER_SEEN:
{
const long plen = buf->get - buf->base;
if(plen >= MIN_FAA604_MSG_LEN)
{
faa604_send_buf (buf);
sent++;
}
else
{
not_faa604++;
log_error("scan_faa604 - length %ld too short",
plen);
}
justify_xbuf (buf, 0);
state = SEARCH;
}
break;
}
justify_xbuf (buf, 0);
state = SEARCH;
break;
#if defined(PARITY_ERR_CH)
case 0:
/*
* Backward compatibility
* except it can change file feeds
*/
if(state == HEADER_SEEN
&& (parity != NULL && *parity != 'n'))
{
*(buf->get -1) = PARITY_ERR_CH;
}
break;
#endif
default:
if(state == SEARCH && isgraph(ch))
state = SKIP;
break;
}
} /* input character loop */
return sent;
}
scan_wmo_binary(xbuf *buf)
#endif
{
int sent = 0;
int ch;
while ((ch = nextc(buf)) != EOB) {
# if defined(SCAN_CHECK)
unsigned prev_crc;
static unsigned crc;
static unsigned offset;
# endif
static enum state {
START,
SEARCH,
SOH_,
SOH_CR_,
SOH_CR_CR_,
HEADER_SEEN,
CR_,
CR_CR_,
CR_CR_NL_
# if defined(SCAN_CHECK)
,
TRAILER_SEEN,
CHECKBYTE_SEEN
# endif
} state = START;
/*
* Incrementing the checksum at this point is not always necessary
* but is done to reduce the number of ADD_CRC() invocations and,
* consequently and hopefully, to reduce problems with maintenance
* and understanding.
*/
# if defined(SCAN_CHECK)
prev_crc = crc;
ADD_CRC(crc, ch);
# endif
switch (state) {
case START:
if (SOH == ch) {
# if defined(SCAN_CHECK)
RESET(offset, crc, ch);
# endif
state = SOH_;
} else {
if (CR != ch && NL != ch) {
udebug("garbage encountered while searching for header");
}
state = SEARCH;
}
break;
case SEARCH:
if (SOH == ch) {
# if defined(SCAN_CHECK)
RESET(offset, crc, ch);
# endif
state = SOH_;
}
break;
case SOH_:
# if defined(SCAN_CHECK)
if (SOH == ch) {
RESET(offset, crc, ch);
} else
# endif
if (CR == ch) {
state = SOH_CR_;
} else {
state = SEARCH;
}
break;
case SOH_CR_:
if (CR == ch) {
state = SOH_CR_CR_;
} else {
state = SEARCH;
}
break;
case SOH_CR_CR_:
if (NL == ch) {
justify_xbuf(buf, 4);
state = HEADER_SEEN;
} else if (CR != ch) {
state = SEARCH;
}
break;
case HEADER_SEEN:
if (CR == ch)
state = CR_;
break;
case CR_:
state = CR == ch
? CR_CR_
: HEADER_SEEN;
break;
case CR_CR_:
if (NL == ch) {
state = CR_CR_NL_;
} else if (CR != ch) {
state = HEADER_SEEN;
}
break;
case CR_CR_NL_:
if (ETX == ch)
{
/* see if we can peek ahead, and if so, does it look like
the start of a new product? */
if(! peek_ahead(buf))
{
state = HEADER_SEEN;
break;
}
}
if (ETX == ch) {
# if defined(SCAN_CHECK)
state = TRAILER_SEEN;
# else
const long plen = buf->get - buf->base;
if(plen >= MIN_WMO_MSG_LEN)
{
wmo_send_buf (buf, 0);
sent++;
}
else
{
not_wmo++;
uerror("scan_wmo_binary: length %ld too short",
plen);
}
justify_xbuf(buf, 0);
state = START;
# endif
} else if (CR == ch) {
state = CR_;
} else {
if (ESC == ch) {
xbuf_rubout(buf);
# if defined(SCAN_CHECK)
crc = prev_crc;
# endif
}
state = HEADER_SEEN;
}
break;
# if defined(SCAN_CHECK)
case TRAILER_SEEN:
state = CHECKBYTE_SEEN;
break;
case CHECKBYTE_SEEN:
if (0 != crc) {
uerror("Checksum (0x%04x) error %s",
crc, wmo_err_ident(buf));
bad_cksum++;
}
else {
const long plen = buf->get - buf->base;
if(plen >= MIN_WMO_MSG_LEN)
{
wmo_send_buf (buf, 2);
sent++;
}
else
{
not_wmo++;
uerror("scan_wmo_binary_crc: length %ld too short",
plen);
}
}
justify_xbuf(buf, 0);
state = START;
break;
# endif
} /* state switch */
# if defined(SCAN_CHECK)
offset++;
# endif
} /* input character loop */
return sent ;
}
int
scan_faa604_parity (xbuf * buf)
{
extern char *parity;
int sent = 0;
int ch;
static enum state
{
SKIP,
SEARCH,
HEADER_SEEN,
PARITY_PIP
}
state = SEARCH;
while ((ch = nextc (buf)) != EOB)
{
switch(ch) {
case SOH:
switch (state) {
case SKIP:
log_debug("Resync skipped %05ld bytes",
(long) (buf->get - buf->base) - 1);
break;
case HEADER_SEEN:
sohetx_missed++;
log_error("Lone SOH error - %s",
faa604_err_ident(buf));
break;
case PARITY_PIP:
parity_errs++;
log_error("Parity error - %s",
faa604_err_ident(buf));
break;
}
justify_xbuf (buf, 1);
state = HEADER_SEEN;
break;
case ETX:
switch (state) {
case SKIP:
#if 0
case SEARCH:
#endif
sohetx_missed++;
log_error("Lone ETX error - %s",
faa604_err_ident(buf));
break;
case HEADER_SEEN:
{
const long plen = buf->get - buf->base;
if(plen >= MIN_FAA604_MSG_LEN)
{
faa604_send_buf (buf);
sent++;
}
else
{
not_faa604++;
log_error("scan_faa604 - length %ld too short",
plen);
}
justify_xbuf (buf, 0);
state = SEARCH;
}
break;
case PARITY_PIP:
parity_errs++;
log_error("Parity error - %s",
faa604_err_ident(buf));
break;
}
justify_xbuf (buf, 0);
state = SEARCH;
break;
case 0:
if(state == HEADER_SEEN
/* && (parity != NULL && *parity != 'n') */
)
{
state = PARITY_PIP;
}
break;
default:
if(state == SEARCH && isgraph(ch))
state = SKIP;
break;
}
} /* input character loop */
return sent;
}
scan_wmo_parity (xbuf * buf)
#endif
{
extern char *parity;
int sent = 0;
int ch;
static enum state
{
SKIP,
SEARCH,
HEADER_SEEN,
PARITY_PIP
}
state = SEARCH;
while ((ch = nextc (buf)) != EOB)
{
switch(ch) {
case SOH:
switch (state) {
case SKIP:
udebug ("Resync skipped %05ld bytes",
(long) (buf->get - buf->base) - 1);
break;
#if 0
case SEARCH:
udebug ("Search %05ld bytes",
(long) (buf->get - buf->base) - 1);
break;
#endif
case HEADER_SEEN:
sohetx_missed++;
uerror("Lone SOH error %s",
wmo_err_ident(buf));
break;
case PARITY_PIP:
bad_cksum++;
uerror("Parity error %s",
wmo_err_ident(buf));
break;
}
justify_xbuf (buf, 1);
state = HEADER_SEEN;
break;
case ETX:
switch (state) {
case SKIP:
#if 0
case SEARCH:
#endif
sohetx_missed++;
uerror("Lone ETX error %s",
wmo_err_ident(buf));
break;
case HEADER_SEEN:
{
const long plen = buf->get - buf->base;
if(plen >= MIN_WMO_MSG_LEN)
{
wmo_send_buf (buf, 0);
sent++;
}
else
{
not_wmo++;
uerror("scan_wmo: length %ld too short",
plen);
}
justify_xbuf (buf, 0);
state = SEARCH;
}
break;
case PARITY_PIP:
bad_cksum++;
uerror("Parity error %s",
wmo_err_ident(buf));
break;
}
justify_xbuf (buf, 0);
state = SEARCH;
break;
#if defined(SCAN_CHECK)
case 0:
if(state == HEADER_SEEN
/* && (parity != NULL && *parity != 'n') */
)
{
state = PARITY_PIP;
}
break;
#elif defined(PARITY_ERR_CH)
case 0:
/*
* Backward compatibility
* except it can change file feeds
*/
if(state == HEADER_SEEN
&& (parity != NULL && *parity != 'n'))
{
*(buf->get -1) = PARITY_ERR_CH;
}
break;
#endif
default:
if(state == SEARCH && isgraph(ch))
state = SKIP;
break;
}
} /* input character loop */
return sent;
}
