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freebsd-skq/libparse/clk_meinberg.c

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Virgin import of ntpd 4.0.98f
1999-12-09 13:01:21 +00:00
/*
Virgin import of ntpd 4.0.99b
2000-01-28 14:55:50 +00:00
* /src/NTP/ntp-4/libparse/clk_meinberg.c,v 4.8 1999/11/28 09:13:50 kardel RELEASE_19991128_A
Virgin import of ntpd 4.0.98f
1999-12-09 13:01:21 +00:00
*
Virgin import of ntpd 4.0.99b
2000-01-28 14:55:50 +00:00
* clk_meinberg.c,v 4.8 1999/11/28 09:13:50 kardel RELEASE_19991128_A
Virgin import of ntpd 4.0.98f
1999-12-09 13:01:21 +00:00
*
* Meinberg clock support
*
* Copyright (C) 1995-1999 by Frank Kardel <kardel@acm.org>
* Copyright (C) 1992-1994 by Frank Kardel, Friedrich-Alexander Universit<EFBFBD>t Erlangen-N<EFBFBD>rnberg, Germany
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#if defined(REFCLOCK) && defined(CLOCK_PARSE) && defined(CLOCK_MEINBERG)
#include "ntp_fp.h"
#include "ntp_unixtime.h"
#include "ntp_calendar.h"
#include "ntp_machine.h"
#include "parse.h"
#ifndef PARSESTREAM
#include <stdio.h>
#else
#include "sys/parsestreams.h"
#endif
#include "ntp_stdlib.h"
#include "ntp_stdlib.h"
#include "mbg_gps166.h"
#include "binio.h"
#include "ascii.h"
/*
* The Meinberg receiver every second sends a datagram of the following form
* (Standard Format)
*
* <STX>D:<dd>.<mm>.<yy>;T:<w>;U:<hh>:<mm>:<ss>;<S><F><D><A><ETX>
* pos: 0 00 00 0 00 0 11 111 1 111 12 2 22 2 22 2 2 2 3 3 3
* 1 23 45 6 78 9 01 234 5 678 90 1 23 4 56 7 8 9 0 1 2
* <STX> = '\002' ASCII start of text
* <ETX> = '\003' ASCII end of text
* <dd>,<mm>,<yy> = day, month, year(2 digits!!)
* <w> = day of week (sunday= 0)
* <hh>,<mm>,<ss> = hour, minute, second
* <S> = '#' if never synced since powerup for DCF C51
* = '#' if not PZF sychronisation available for PZF 535/509
* = ' ' if ok
* <F> = '*' if time comes from internal quartz
* = ' ' if completely synched
* <D> = 'S' if daylight saving time is active
* = 'U' if time is represented in UTC
* = ' ' if no special condition exists
* <A> = '!' during the hour preceeding an daylight saving time
* start/end change
* = 'A' leap second insert warning
* = ' ' if no special condition exists
*
* Extended data format (PZFUERL for PZF type clocks)
*
* <STX><dd>.<mm>.<yy>; <w>; <hh>:<mm>:<ss>; <U><S><F><D><A><L><R><ETX>
* pos: 0 00 0 00 0 00 11 1 11 11 1 11 2 22 22 2 2 2 2 2 3 3 3
* 1 23 4 56 7 89 01 2 34 56 7 89 0 12 34 5 6 7 8 9 0 1 2
* <STX> = '\002' ASCII start of text
* <ETX> = '\003' ASCII end of text
* <dd>,<mm>,<yy> = day, month, year(2 digits!!)
* <w> = day of week (sunday= 0)
* <hh>,<mm>,<ss> = hour, minute, second
* <U> = 'U' UTC time display
* <S> = '#' if never synced since powerup else ' ' for DCF C51
* '#' if not PZF sychronisation available else ' ' for PZF 535/509
* <F> = '*' if time comes from internal quartz else ' '
* <D> = 'S' if daylight saving time is active else ' '
* <A> = '!' during the hour preceeding an daylight saving time
* start/end change
* <L> = 'A' LEAP second announcement
* <R> = 'R' alternate antenna
*
* Meinberg GPS166 receiver
*
* You must get the Uni-Erlangen firmware for the GPS receiver support
* to work to full satisfaction !
*
* <STX><dd>.<mm>.<yy>; <w>; <hh>:<mm>:<ss>; <+/-><00:00>; <U><S><F><D><A><L><R><L>; <position...><ETX>
*
* 000000000111111111122222222223333333333444444444455555555556666666
* 123456789012345678901234567890123456789012345678901234567890123456
* \x0209.07.93; 5; 08:48:26; +00:00; #*S!A L; 49.5736N 11.0280E 373m\x03
*
*
* <STX> = '\002' ASCII start of text
* <ETX> = '\003' ASCII end of text
* <dd>,<mm>,<yy> = day, month, year(2 digits!!)
* <w> = day of week (sunday= 0)
* <hh>,<mm>,<ss> = hour, minute, second
* <+/->,<00:00> = offset to UTC
* <S> = '#' if never synced since powerup else ' '
* <F> = '*' if position is not confirmed else ' '
* <D> = 'S' if daylight saving time is active else ' '
* <A> = '!' during the hour preceeding an daylight saving time
* start/end change
* <L> = 'A' LEAP second announcement
* <R> = 'R' alternate antenna (reminiscent of PZF535) usually ' '
* <L> = 'L' on 23:59:60
*
* Binary messages have a lead in for a fixed header of SOH
*/
/*--------------------------------------------------------------*/
/* Name: csum() */
/* */
/* Purpose: Compute a checksum about a number of bytes */
/* */
/* Input: uchar *p address of the first byte */
/* short n the number of bytes */
/* */
/* Output: -- */
/* */
/* Ret val: the checksum */
/*+-------------------------------------------------------------*/
unsigned long
mbg_csum(
unsigned char *p,
unsigned int n
)
{
unsigned long sum = 0;
short i;
for ( i = 0; i < n; i++ )
sum += *p++;
return( sum );
} /* csum */
void
get_mbg_header(
unsigned char **bufpp,
GPS_MSG_HDR *headerp
)
{
headerp->gps_cmd = get_lsb_short(bufpp);
headerp->gps_len = get_lsb_short(bufpp);
headerp->gps_data_csum = get_lsb_short(bufpp);
headerp->gps_hdr_csum = get_lsb_short(bufpp);
}
static struct format meinberg_fmt[] =
{
{
{
{ 3, 2}, { 6, 2}, { 9, 2},
{ 18, 2}, { 21, 2}, { 24, 2},
{ 14, 1}, { 27, 4}, { 29, 1},
},
(const unsigned char *)"\2D: . . ;T: ;U: . . ; \3",
0
},
{ /* special extended FAU Erlangen extended format */
{
{ 1, 2}, { 4, 2}, { 7, 2},
{ 14, 2}, { 17, 2}, { 20, 2},
{ 11, 1}, { 25, 4}, { 27, 1},
},
(const unsigned char *)"\2 . . ; ; : : ; \3",
MBG_EXTENDED
},
{ /* special extended FAU Erlangen GPS format */
{
{ 1, 2}, { 4, 2}, { 7, 2},
{ 14, 2}, { 17, 2}, { 20, 2},
{ 11, 1}, { 32, 7}, { 35, 1},
{ 25, 2}, { 28, 2}, { 24, 1}
},
(const unsigned char *)"\2 . . ; ; : : ; : ; ; . . ",
0
}
};
static u_long cvt_meinberg P((unsigned char *, int, struct format *, clocktime_t *, void *));
static u_long cvt_mgps P((unsigned char *, int, struct format *, clocktime_t *, void *));
static u_long mbg_input P((parse_t *, unsigned int, timestamp_t *));
static u_long gps_input P((parse_t *, unsigned int, timestamp_t *));
struct msg_buf
{
unsigned short len; /* len to fill */
unsigned short phase; /* current input phase */
};
#define MBG_NONE 0 /* no data input */
#define MBG_HEADER 1 /* receiving header */
#define MBG_DATA 2 /* receiving data */
#define MBG_STRING 3 /* receiving standard data message */
clockformat_t clock_meinberg[] =
{
{
mbg_input, /* normal input handling */
cvt_meinberg, /* Meinberg conversion */
pps_one, /* easy PPS monitoring */
0, /* conversion configuration */
"Meinberg Standard", /* Meinberg simple format - beware */
32, /* string buffer */
0 /* no private data (complete pakets) */
},
{
mbg_input, /* normal input handling */
cvt_meinberg, /* Meinberg conversion */
pps_one, /* easy PPS monitoring */
0, /* conversion configuration */
"Meinberg Extended", /* Meinberg enhanced format */
32, /* string buffer */
0 /* no private data (complete pakets) */
},
{
gps_input, /* no input handling */
cvt_mgps, /* Meinberg GPS166 conversion */
pps_one, /* easy PPS monitoring */
(void *)&meinberg_fmt[2], /* conversion configuration */
"Meinberg GPS Extended", /* Meinberg FAU GPS format */
512, /* string buffer */
sizeof(struct msg_buf) /* no private data (complete pakets) */
}
};
/*
* cvt_meinberg
*
* convert simple type format
*/
static u_long
cvt_meinberg(
unsigned char *buffer,
int size,
struct format *unused,
clocktime_t *clock_time,
void *local
)
{
struct format *format;
/*
* select automagically correct data format
*/
if (Strok(buffer, meinberg_fmt[0].fixed_string))
{
format = &meinberg_fmt[0];
}
else
{
if (Strok(buffer, meinberg_fmt[1].fixed_string))
{
format = &meinberg_fmt[1];
}
else
{
return CVT_FAIL|CVT_BADFMT;
}
}
/*
* collect data
*/
if (Stoi(&buffer[format->field_offsets[O_DAY].offset], &clock_time->day,
format->field_offsets[O_DAY].length) ||
Stoi(&buffer[format->field_offsets[O_MONTH].offset], &clock_time->month,
format->field_offsets[O_MONTH].length) ||
Stoi(&buffer[format->field_offsets[O_YEAR].offset], &clock_time->year,
format->field_offsets[O_YEAR].length) ||
Stoi(&buffer[format->field_offsets[O_HOUR].offset], &clock_time->hour,
format->field_offsets[O_HOUR].length) ||
Stoi(&buffer[format->field_offsets[O_MIN].offset], &clock_time->minute,
format->field_offsets[O_MIN].length) ||
Stoi(&buffer[format->field_offsets[O_SEC].offset], &clock_time->second,
format->field_offsets[O_SEC].length))
{
return CVT_FAIL|CVT_BADFMT;
}
else
{
unsigned char *f = &buffer[format->field_offsets[O_FLAGS].offset];
clock_time->usecond = 0;
clock_time->flags = PARSEB_S_LEAP;
if (clock_time->second == 60)
clock_time->flags |= PARSEB_LEAPSECOND;
/*
* in the extended timecode format we have also the
* indication that the timecode is in UTC
* for compatibilty reasons we start at the USUAL
* offset (POWERUP flag) and know that the UTC indication
* is the character before the powerup flag
*/
if ((format->flags & MBG_EXTENDED) && (f[-1] == 'U'))
{
/*
* timecode is in UTC
*/
clock_time->utcoffset = 0; /* UTC */
clock_time->flags |= PARSEB_UTC;
}
else
{
/*
* only calculate UTC offset if MET/MED is in time code
* or we have the old time code format, where we do not
* know whether it is UTC time or MET/MED
* pray that nobody switches to UTC in the *old* standard time code
* ROMS !!!! The new ROMS have 'U' at the ZONE field - good.
*/
switch (buffer[format->field_offsets[O_ZONE].offset])
{
case ' ':
clock_time->utcoffset = -1*60*60; /* MET */
break;
case 'S':
clock_time->utcoffset = -2*60*60; /* MED */
break;
case 'U':
/*
* timecode is in UTC
*/
clock_time->utcoffset = 0; /* UTC */
clock_time->flags |= PARSEB_UTC;
break;
default:
return CVT_FAIL|CVT_BADFMT;
}
}
/*
* gather status flags
*/
if (buffer[format->field_offsets[O_ZONE].offset] == 'S')
clock_time->flags |= PARSEB_DST;
if (f[0] == '#')
clock_time->flags |= PARSEB_POWERUP;
if (f[1] == '*')
clock_time->flags |= PARSEB_NOSYNC;
if (f[3] == '!')
clock_time->flags |= PARSEB_ANNOUNCE;
/*
* oncoming leap second
* 'a' code not confirmed - earth is not
* expected to speed up
*/
if (f[3] == 'A')
clock_time->flags |= PARSEB_LEAPADD;
if (f[3] == 'a')
clock_time->flags |= PARSEB_LEAPDEL;
if (format->flags & MBG_EXTENDED)
{
clock_time->flags |= PARSEB_S_ANTENNA;
/*
* DCF77 does not encode the direction -
* so we take the current default -
* earth slowing down
*/
clock_time->flags &= ~PARSEB_LEAPDEL;
if (f[4] == 'A')
clock_time->flags |= PARSEB_LEAPADD;
if (f[5] == 'R')
clock_time->flags |= PARSEB_ALTERNATE;
}
return CVT_OK;
}
}
/*
* mbg_input
*
* grep data from input stream
*/
static u_long
mbg_input(
parse_t *parseio,
unsigned int ch,
timestamp_t *tstamp
)
{
unsigned int rtc;
Virgin import of ntpd 4.1.0
2001-08-29 14:35:15 +00:00
parseprintf(DD_PARSE, ("mbg_input(0x%lx, 0x%x, ...)\n", (long)parseio, ch));
Virgin import of ntpd 4.0.98f
1999-12-09 13:01:21 +00:00
switch (ch)
{
case STX:
parseprintf(DD_PARSE, ("mbg_input: STX seen\n"));
parseio->parse_index = 1;
parseio->parse_data[0] = ch;
parseio->parse_dtime.parse_stime = *tstamp; /* collect timestamp */
return PARSE_INP_SKIP;
case ETX:
parseprintf(DD_PARSE, ("mbg_input: ETX seen\n"));
if ((rtc = parse_addchar(parseio, ch)) == PARSE_INP_SKIP)
return parse_end(parseio);
else
return rtc;
default:
return parse_addchar(parseio, ch);
}
}
/*
* cvt_mgps
*
* convert Meinberg GPS format
*/
static u_long
cvt_mgps(
unsigned char *buffer,
int size,
struct format *format,
clocktime_t *clock_time,
void *local
)
{
if (!Strok(buffer, format->fixed_string))
{
return cvt_meinberg(buffer, size, format, clock_time, local);
}
else
{
if (Stoi(&buffer[format->field_offsets[O_DAY].offset], &clock_time->day,
format->field_offsets[O_DAY].length) ||
Stoi(&buffer[format->field_offsets[O_MONTH].offset], &clock_time->month,
format->field_offsets[O_MONTH].length) ||
Stoi(&buffer[format->field_offsets[O_YEAR].offset], &clock_time->year,
format->field_offsets[O_YEAR].length) ||
Stoi(&buffer[format->field_offsets[O_HOUR].offset], &clock_time->hour,
format->field_offsets[O_HOUR].length) ||
Stoi(&buffer[format->field_offsets[O_MIN].offset], &clock_time->minute,
format->field_offsets[O_MIN].length) ||
Stoi(&buffer[format->field_offsets[O_SEC].offset], &clock_time->second,
format->field_offsets[O_SEC].length))
{
return CVT_FAIL|CVT_BADFMT;
}
else
{
long h;
unsigned char *f = &buffer[format->field_offsets[O_FLAGS].offset];
clock_time->flags = PARSEB_S_LEAP|PARSEB_S_POSITION;
clock_time->usecond = 0;
/*
* calculate UTC offset
*/
if (Stoi(&buffer[format->field_offsets[O_UTCHOFFSET].offset], &h,
format->field_offsets[O_UTCHOFFSET].length))
{
return CVT_FAIL|CVT_BADFMT;
}
else
{
if (Stoi(&buffer[format->field_offsets[O_UTCMOFFSET].offset], &clock_time->utcoffset,
format->field_offsets[O_UTCMOFFSET].length))
{
return CVT_FAIL|CVT_BADFMT;
}
clock_time->utcoffset += TIMES60(h);
clock_time->utcoffset = TIMES60(clock_time->utcoffset);
if (buffer[format->field_offsets[O_UTCSOFFSET].offset] != '-')
{
clock_time->utcoffset = -clock_time->utcoffset;
}
}
/*
* gather status flags
*/
if (buffer[format->field_offsets[O_ZONE].offset] == 'S')
clock_time->flags |= PARSEB_DST;
if (clock_time->utcoffset == 0)
clock_time->flags |= PARSEB_UTC;
/*
* no sv's seen - no time & position
*/
if (f[0] == '#')
clock_time->flags |= PARSEB_POWERUP;
/*
* at least one sv seen - time (for last position)
*/
if (f[1] == '*')
clock_time->flags |= PARSEB_NOSYNC;
else
if (!(clock_time->flags & PARSEB_POWERUP))
clock_time->flags |= PARSEB_POSITION;
/*
* oncoming zone switch
*/
if (f[3] == '!')
clock_time->flags |= PARSEB_ANNOUNCE;
/*
* oncoming leap second
* 'a' code not confirmed - earth is not
* expected to speed up
*/
if (f[4] == 'A')
clock_time->flags |= PARSEB_LEAPADD;
if (f[4] == 'a')
clock_time->flags |= PARSEB_LEAPDEL;
/*
* f[5] == ' '
*/
/*
* this is the leap second
*/
if ((f[6] == 'L') || (clock_time->second == 60))
clock_time->flags |= PARSEB_LEAPSECOND;
return CVT_OK;
}
}
}
/*
* gps_input
*
* grep binary data from input stream
*/
static u_long
gps_input(
parse_t *parseio,
unsigned int ch,
timestamp_t *tstamp
)
{
CSUM calc_csum; /* used to compare the incoming csums */
GPS_MSG_HDR header;
struct msg_buf *msg_buf;
msg_buf = (struct msg_buf *)parseio->parse_pdata;
Virgin import of ntpd 4.1.0
2001-08-29 14:35:15 +00:00
parseprintf(DD_PARSE, ("gps_input(0x%lx, 0x%x, ...)\n", (long)parseio, ch));
Virgin import of ntpd 4.0.98f
1999-12-09 13:01:21 +00:00
if (!msg_buf)
return PARSE_INP_SKIP;
if ( msg_buf->phase == MBG_NONE )
{ /* not receiving yet */
switch (ch)
{
case SOH:
parseprintf(DD_PARSE, ("gps_input: SOH seen\n"));
msg_buf->len = sizeof( header ); /* prepare to receive msg header */
msg_buf->phase = MBG_HEADER; /* receiving header */
break;
case STX:
parseprintf(DD_PARSE, ("gps_input: STX seen\n"));
msg_buf->len = 0;
msg_buf->phase = MBG_STRING; /* prepare to receive ASCII ETX delimited message */
parseio->parse_index = 1;
parseio->parse_data[0] = ch;
break;
default:
return PARSE_INP_SKIP; /* keep searching */
}
parseio->parse_dtime.parse_msglen = 1; /* reset buffer pointer */
parseio->parse_dtime.parse_msg[0] = ch; /* fill in first character */
parseio->parse_dtime.parse_stime = *tstamp; /* collect timestamp */
return PARSE_INP_SKIP;
}
/* SOH/STX has already been received */
/* save incoming character in both buffers if needbe */
if ((msg_buf->phase == MBG_STRING) &&
(parseio->parse_index < parseio->parse_dsize))
parseio->parse_data[parseio->parse_index++] = ch;
parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;
if (parseio->parse_dtime.parse_msglen > sizeof(parseio->parse_dtime.parse_msg))
{
msg_buf->phase = MBG_NONE; /* buffer overflow - discard */
parseio->parse_data[parseio->parse_index] = '\0';
memcpy(parseio->parse_ldata, parseio->parse_data, (unsigned)(parseio->parse_index+1));
parseio->parse_ldsize = parseio->parse_index+1;
return PARSE_INP_DATA;
}
switch (msg_buf->phase)
{
case MBG_HEADER:
case MBG_DATA:
msg_buf->len--;
if ( msg_buf->len ) /* transfer not complete */
return PARSE_INP_SKIP;
parseprintf(DD_PARSE, ("gps_input: %s complete\n", (msg_buf->phase == MBG_DATA) ? "data" : "header"));
break;
case MBG_STRING:
if ((ch == ETX) || (parseio->parse_index >= parseio->parse_dsize))
{
msg_buf->phase = MBG_NONE;
parseprintf(DD_PARSE, ("gps_input: string complete\n"));
parseio->parse_data[parseio->parse_index] = '\0';
memcpy(parseio->parse_ldata, parseio->parse_data, (unsigned)(parseio->parse_index+1));
parseio->parse_ldsize = parseio->parse_index+1;
parseio->parse_index = 0;
return PARSE_INP_TIME;
}
else
{
return PARSE_INP_SKIP;
}
}
/* cnt == 0, so the header or the whole message is complete */
if ( msg_buf->phase == MBG_HEADER )
{ /* header complete now */
unsigned char *datap = parseio->parse_dtime.parse_msg + 1;
get_mbg_header(&datap, &header);
parseprintf(DD_PARSE, ("gps_input: header: cmd 0x%x, len %d, dcsum 0x%x, hcsum 0x%x\n",
(int)header.gps_cmd, (int)header.gps_len, (int)header.gps_data_csum,
(int)header.gps_hdr_csum));
calc_csum = mbg_csum( (unsigned char *) parseio->parse_dtime.parse_msg + 1, (unsigned short)6 );
if ( calc_csum != header.gps_hdr_csum )
{
parseprintf(DD_PARSE, ("gps_input: header checksum mismatch expected 0x%x, got 0x%x\n",
(int)calc_csum, (int)mbg_csum( (unsigned char *) parseio->parse_dtime.parse_msg, (unsigned short)6 )));
msg_buf->phase = MBG_NONE; /* back to hunting mode */
return PARSE_INP_DATA; /* invalid header checksum received - pass up for detection */
}
if ((header.gps_len == 0) || /* no data to wait for */
(header.gps_len >= (sizeof (parseio->parse_dtime.parse_msg) - sizeof(header) - 1))) /* blows anything we have space for */
{
msg_buf->phase = MBG_NONE; /* back to hunting mode */
return (header.gps_len == 0) ? PARSE_INP_DATA : PARSE_INP_SKIP; /* message complete/throwaway */
}
parseprintf(DD_PARSE, ("gps_input: expecting %d bytes of data message\n", (int)header.gps_len));
msg_buf->len = header.gps_len;/* save number of bytes to wait for */
msg_buf->phase = MBG_DATA; /* flag header already complete */
return PARSE_INP_SKIP;
}
parseprintf(DD_PARSE, ("gps_input: message data complete\n"));
/* Header and data have been received. The header checksum has been */
/* checked */
msg_buf->phase = MBG_NONE; /* back to hunting mode */
return PARSE_INP_DATA; /* message complete, must be evaluated */
}
#else /* not (REFCLOCK && CLOCK_PARSE && CLOCK_MEINBERG) */
int clk_meinberg_bs;
#endif /* not (REFCLOCK && CLOCK_PARSE && CLOCK_MEINBERG) */
/*
* History:
*
* clk_meinberg.c,v
Virgin import of ntpd 4.0.99b
2000-01-28 14:55:50 +00:00
* Revision 4.8 1999/11/28 09:13:50 kardel
* RECON_4_0_98F
*
Virgin import of ntpd 4.0.98f
1999-12-09 13:01:21 +00:00
* Revision 4.7 1999/02/21 11:09:14 kardel
* cleanup
*
* Revision 4.6 1998/06/14 21:09:36 kardel
* Sun acc cleanup
*
* Revision 4.5 1998/06/13 15:18:54 kardel
* fix mem*() to b*() function macro emulation
*
* Revision 4.4 1998/06/13 12:03:23 kardel
* fix SYSV clock name clash
*
* Revision 4.3 1998/06/12 15:22:28 kardel
* fix prototypes
*
* Revision 4.2 1998/05/24 16:14:42 kardel
* support current Meinberg standard data formats
*
* Revision 4.1 1998/05/24 09:39:52 kardel
* implementation of the new IO handling model
*
* Revision 4.0 1998/04/10 19:45:29 kardel
* Start 4.0 release version numbering
*
* from V3 3.23 - log info deleted 1998/04/11 kardel
*
*/
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