/*!
* \file rtklib_rtcm.cc
* \brief RTCM functions
* \authors
* - 2007-2013, T. Takasu
*
- 2017, Javier Arribas
*
- 2017, Carles Fernandez
*
*
* This is a derived work from RTKLIB http://www.rtklib.com/
* The original source code at https://github.com/tomojitakasu/RTKLIB is
* released under the BSD 2-clause license with an additional exclusive clause
* that does not apply here. This additional clause is reproduced below:
*
* " The software package includes some companion executive binaries or shared
* libraries necessary to execute APs on Windows. These licenses succeed to the
* original ones of these software. "
*
* Neither the executive binaries nor the shared libraries are required by, used
* or included in GNSS-SDR.
*
* -------------------------------------------------------------------------
* Copyright (C) 2007-2013, T. Takasu
* Copyright (C) 2017, Javier Arribas
* Copyright (C) 2017, Carles Fernandez
* All rights reserved.
*
* SPDX-License-Identifier: BSD-2-Clause
*
*
*----------------------------------------------------------------------------*/
#include "rtklib_rtcm.h"
#include "rtklib_rtkcmn.h"
// extern int encode_rtcm3(rtcm_t *rtcm, int type, int sync);
/* initialize rtcm control -----------------------------------------------------
* initialize rtcm control struct and reallocate memory for observation and
* ephemeris buffer in rtcm control struct
* args : rtcm_t *raw IO rtcm control struct
* return : status (1:ok,0:memory allocation error)
*-----------------------------------------------------------------------------*/
int init_rtcm(rtcm_t *rtcm)
{
gtime_t time0 = {0, 0.0};
obsd_t data0 = {{0, 0.0}, 0, 0, {0}, {0}, {0}, {0.0}, {0.0}, {0.0}};
eph_t eph0 = {0, -1, -1, 0, 0, 0, 0, 0, {0, 0.0}, {0, 0.0}, {0, 0.0},
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, {0.0}, {0.0}, 0.0, 0.0};
geph_t geph0 = {0, -1, 0, 0, 0, 0, {0, 0.0}, {0, 0.0}, {0.0}, {0.0}, {0.0},
0.0, 0.0, 0.0};
ssr_t ssr0 = {{{0, 0.0}}, {0.0}, {0}, 0, 0, 0, 0, {0.0}, {0.0}, {0.0}, 0.0, {0.0}, {0.0}, {0.0}, 0.0, 0.0, '0'};
int i;
int j;
trace(3, "init_rtcm:\n");
rtcm->staid = rtcm->stah = rtcm->seqno = rtcm->outtype = 0;
rtcm->time = rtcm->time_s = time0;
rtcm->sta.name[0] = rtcm->sta.marker[0] = '\0';
rtcm->sta.antdes[0] = rtcm->sta.antsno[0] = '\0';
rtcm->sta.rectype[0] = rtcm->sta.recver[0] = rtcm->sta.recsno[0] = '\0';
rtcm->sta.antsetup = rtcm->sta.itrf = rtcm->sta.deltype = 0;
for (i = 0; i < 3; i++)
{
rtcm->sta.pos[i] = rtcm->sta.del[i] = 0.0;
}
rtcm->sta.hgt = 0.0;
rtcm->dgps = nullptr;
for (i = 0; i < MAXSAT; i++)
{
rtcm->ssr[i] = ssr0;
}
rtcm->msg[0] = rtcm->msgtype[0] = rtcm->opt[0] = '\0';
for (i = 0; i < 6; i++)
{
rtcm->msmtype[i][0] = '\0';
}
rtcm->obsflag = rtcm->ephsat = 0;
for (i = 0; i < MAXSAT; i++)
{
for (j = 0; j < NFREQ + NEXOBS; j++)
{
rtcm->cp[i][j] = 0.0;
rtcm->lock[i][j] = rtcm->loss[i][j] = 0;
rtcm->lltime[i][j] = time0;
}
}
rtcm->nbyte = rtcm->nbit = rtcm->len = 0;
rtcm->word = 0;
for (i = 0; i < 100; i++)
{
rtcm->nmsg2[i] = 0;
}
for (i = 0; i < 300; i++)
{
rtcm->nmsg3[i] = 0;
}
rtcm->obs.data = nullptr;
rtcm->nav.eph = nullptr;
rtcm->nav.geph = nullptr;
/* reallocate memory for observation and ephemris buffer */
if (!(rtcm->obs.data = static_cast(malloc(sizeof(obsd_t) * MAXOBS))) ||
!(rtcm->nav.eph = static_cast(malloc(sizeof(eph_t) * MAXSAT))) ||
!(rtcm->nav.geph = static_cast(malloc(sizeof(geph_t) * MAXPRNGLO))))
{
free_rtcm(rtcm);
return 0;
}
rtcm->obs.n = 0;
rtcm->nav.n = MAXSAT;
rtcm->nav.ng = MAXPRNGLO;
for (i = 0; i < MAXOBS; i++)
{
rtcm->obs.data[i] = data0;
}
for (i = 0; i < MAXSAT; i++)
{
rtcm->nav.eph[i] = eph0;
}
for (i = 0; i < MAXPRNGLO; i++)
{
rtcm->nav.geph[i] = geph0;
}
return 1;
}
/* free rtcm control ----------------------------------------------------------
* free observation and ephemris buffer in rtcm control struct
* args : rtcm_t *raw IO rtcm control struct
* return : none
*-----------------------------------------------------------------------------*/
void free_rtcm(rtcm_t *rtcm)
{
trace(3, "free_rtcm:\n");
/* free memory for observation and ephemeris buffer */
free(rtcm->obs.data);
rtcm->obs.data = nullptr;
rtcm->obs.n = 0;
free(rtcm->nav.eph);
rtcm->nav.eph = nullptr;
rtcm->nav.n = 0;
free(rtcm->nav.geph);
rtcm->nav.geph = nullptr;
rtcm->nav.ng = 0;
}
/* input rtcm 2 message from stream --------------------------------------------
* fetch next rtcm 2 message and input a message from byte stream
* args : rtcm_t *rtcm IO rtcm control struct
* unsigned char data I stream data (1 byte)
* return : status (-1: error message, 0: no message, 1: input observation data,
* 2: input ephemeris, 5: input station pos/ant parameters,
* 6: input time parameter, 7: input dgps corrections,
* 9: input special message)
* notes : before firstly calling the function, time in rtcm control struct has
* to be set to the approximate time within 1/2 hour in order to resolve
* ambiguity of time in rtcm messages.
* supported msgs RTCM ver.2: 1,3,9,14,16,17,18,19,22
* refer [1] for RTCM ver.2
*-----------------------------------------------------------------------------*/
int input_rtcm2(rtcm_t *rtcm, unsigned char data)
{
unsigned char preamb;
int i;
trace(5, "input_rtcm2: data=%02x\n", data);
if ((data & 0xC0) != 0x40)
{
return 0; /* ignore if upper 2bit != 01 */
}
for (i = 0; i < 6; i++, data >>= 1)
{ /* decode 6-of-8 form */
rtcm->word = (rtcm->word << 1) + (data & 1);
/* synchronize frame */
if (rtcm->nbyte == 0)
{
preamb = static_cast(rtcm->word >> 22);
if (rtcm->word & 0x40000000)
{
preamb ^= 0xFF; /* decode preamble */
}
if (preamb != RTCM2PREAMB)
{
continue;
}
/* check parity */
if (!decode_word(rtcm->word, rtcm->buff))
{
continue;
}
rtcm->nbyte = 3;
rtcm->nbit = 0;
continue;
}
if (++rtcm->nbit < 30)
{
continue;
}
rtcm->nbit = 0;
/* check parity */
if (!decode_word(rtcm->word, rtcm->buff + rtcm->nbyte))
{
trace(2, "rtcm2 partity error: i=%d word=%08x\n", i, rtcm->word);
rtcm->nbyte = 0;
rtcm->word &= 0x3;
continue;
}
rtcm->nbyte += 3;
if (rtcm->nbyte == 6)
{
rtcm->len = (rtcm->buff[5] >> 3) * 3 + 6;
}
if (rtcm->nbyte < rtcm->len)
{
continue;
}
rtcm->nbyte = 0;
rtcm->word &= 0x3;
/* decode rtcm2 message */
return decode_rtcm2(rtcm);
}
return 0;
}
/* input rtcm 3 message from stream --------------------------------------------
* fetch next rtcm 3 message and input a message from byte stream
* args : rtcm_t *rtcm IO rtcm control struct
* unsigned char data I stream data (1 byte)
* return : status (-1: error message, 0: no message, 1: input observation data,
* 2: input ephemeris, 5: input station pos/ant parameters,
* 10: input ssr messages)
* notes : before firstly calling the function, time in rtcm control struct has
* to be set to the approximate time within 1/2 week in order to resolve
* ambiguity of time in rtcm messages.
*
* to specify input options, set rtcm->opt to the following option
* strings separated by spaces.
*
* -EPHALL : input all ephemerides
* -STA=nnn : input only message with STAID=nnn
* -GLss : select signal ss for GPS MSM (ss=1C,1P,...)
* -RLss : select signal ss for GLO MSM (ss=1C,1P,...)
* -ELss : select signal ss for GAL MSM (ss=1C,1B,...)
* -JLss : select signal ss for QZS MSM (ss=1C,2C,...)
* -CLss : select signal ss for BDS MSM (ss=2I,7I,...)
*
* supported RTCM 3 messages
* (ref [2][3][4][5][6][7][8][9][10][11][12][13][14][15])
*
* TYPE GPS GLOASS GALILEO QZSS BEIDOU SBAS
* ----------------------------------------------------------------------
* OBS C-L1 : 1001~ 1009~ - - - -
* F-L1 : 1002 1010 - - - -
* C-L12 : 1003~ 1011~ - - - -
* F-L12 : 1004 1012 - - - -
*
* NAV : 1019 1020 1045* 1044* 1047* -
* - - 1046* - - -
*
* MSM 1 : 1071~ 1081~ 1091~ 1111*~ 1121*~ 1101*~
* 2 : 1072~ 1082~ 1092~ 1112*~ 1122*~ 1102*~
* 3 : 1073~ 1083~ 1093~ 1113*~ 1123*~ 1103*~
* 4 : 1074 1084 1094 1114* 1124* 1104*
* 5 : 1075 1085 1095 1115* 1125* 1105*
* 6 : 1076 1086 1096 1116* 1126* 1106*
* 7 : 1077 1087 1097 1117* 1127* 1107*
*
* SSR OBT : 1057 1063 1240* 1246* 1258* -
* CLK : 1058 1064 1241* 1247* 1259* -
* BIAS : 1059 1065 1242* 1248* 1260* -
* OBTCLK: 1060 1066 1243* 1249* 1261* -
* URA : 1061 1067 1244* 1250* 1262* -
* HRCLK : 1062 1068 1245* 1251* 1263* -
*
* ANT INFO : 1005 1006 1007 1008 1033
* ----------------------------------------------------------------------
* (* draft, ~ only encode)
*
* for MSM observation data with multiple signals for a frequency,
* a signal is selected according to internal priority. to select
* a specified signal, use the input options.
*
* rtcm3 message format:
* +----------+--------+-----------+--------------------+----------+
* | preamble | 000000 | length | data message | parity |
* +----------+--------+-----------+--------------------+----------+
* |<-- 8 --->|<- 6 -->|<-- 10 --->|<--- length x 8 --->|<-- 24 -->|
*
*-----------------------------------------------------------------------------*/
int input_rtcm3(rtcm_t *rtcm, unsigned char data)
{
trace(5, "input_rtcm3: data=%02x\n", data);
/* synchronize frame */
if (rtcm->nbyte == 0)
{
if (data != RTCM3PREAMB)
{
return 0;
}
rtcm->buff[rtcm->nbyte++] = data;
return 0;
}
rtcm->buff[rtcm->nbyte++] = data;
if (rtcm->nbyte == 3)
{
rtcm->len = getbitu(rtcm->buff, 14, 10) + 3; /* length without parity */
}
if (rtcm->nbyte < 3 || rtcm->nbyte < rtcm->len + 3)
{
return 0;
}
rtcm->nbyte = 0;
/* check parity */
if (rtk_crc24q(rtcm->buff, rtcm->len) != getbitu(rtcm->buff, rtcm->len * 8, 24))
{
trace(2, "rtcm3 parity error: len=%d\n", rtcm->len);
return 0;
}
/* decode rtcm3 message */
return decode_rtcm3(rtcm);
}
/* input rtcm 2 message from file ----------------------------------------------
* fetch next rtcm 2 message and input a message from file
* args : rtcm_t *rtcm IO rtcm control struct
* FILE *fp I file pointer
* return : status (-2: end of file, -1...10: same as above)
* notes : same as above
*-----------------------------------------------------------------------------*/
int input_rtcm2f(rtcm_t *rtcm, FILE *fp)
{
int i;
int data = 0;
int ret;
trace(4, "input_rtcm2f: data=%02x\n", data);
for (i = 0; i < 4096; i++)
{
if ((data = fgetc(fp)) == EOF)
{
return -2;
}
if ((ret = input_rtcm2(rtcm, static_cast(data))))
{
return ret;
}
}
return 0; /* return at every 4k bytes */
}
/* input rtcm 3 message from file ----------------------------------------------
* fetch next rtcm 3 message and input a message from file
* args : rtcm_t *rtcm IO rtcm control struct
* FILE *fp I file pointer
* return : status (-2: end of file, -1...10: same as above)
* notes : same as above
*-----------------------------------------------------------------------------*/
int input_rtcm3f(rtcm_t *rtcm, FILE *fp)
{
int i;
int data = 0;
int ret;
trace(4, "input_rtcm3f: data=%02x\n", data);
for (i = 0; i < 4096; i++)
{
if ((data = fgetc(fp)) == EOF)
{
return -2;
}
if ((ret = input_rtcm3(rtcm, static_cast(data))))
{
return ret;
}
}
return 0; /* return at every 4k bytes */
}
/* generate rtcm 2 message -----------------------------------------------------
* generate rtcm 2 message
* args : rtcm_t *rtcm IO rtcm control struct
* int type I message type
* int sync I sync flag (1:another message follows)
* return : status (1:ok,0:error)
*-----------------------------------------------------------------------------*/
int gen_rtcm2(rtcm_t *rtcm, int type, int sync)
{
trace(4, "gen_rtcm2: type=%d sync=%d\n", type, sync);
rtcm->nbit = rtcm->len = rtcm->nbyte = 0;
/* not yet implemented */
return 0;
}
// /* generate rtcm 3 message -----------------------------------------------------
// * generate rtcm 3 message
// * args : rtcm_t *rtcm IO rtcm control struct
// * int type I message type
// * int sync I sync flag (1:another message follows)
// * return : status (1:ok,0:error)
// *-----------------------------------------------------------------------------*/
// int gen_rtcm3(rtcm_t *rtcm, int type, int sync)
// {
// unsigned int crc;
// int i = 0;
//
// trace(4, "gen_rtcm3: type=%d sync=%d\n", type, sync);
//
// rtcm->nbit = rtcm->len = rtcm->nbyte = 0;
//
// /* set preamble and reserved */
// setbitu(rtcm->buff, i, 8, RTCM3PREAMB); i += 8;
// setbitu(rtcm->buff, i, 6, 0 ); i += 6;
// setbitu(rtcm->buff, i, 10, 0 ); i += 10;
//
// /* encode rtcm 3 message body */
// if (!encode_rtcm3(rtcm, type, sync)) return 0;
//
// /* padding to align 8 bit boundary */
// for (i = rtcm->nbit;i%8;i++)
// {
// setbitu(rtcm->buff, i, 1, 0);
// }
// /* message length (header+data) (bytes) */
// if ((rtcm->len = i/8) >= 3+1024)
// {
// trace(2, "generate rtcm 3 message length error len=%d\n", rtcm->len-3);
// rtcm->nbit = rtcm->len = 0;
// return 0;
// }
// /* message length without header and parity */
// setbitu(rtcm->buff, 14, 10, rtcm->len-3);
//
// /* crc-24q */
// crc = rtk_crc24q(rtcm->buff, rtcm->len);
// setbitu(rtcm->buff, i, 24, crc);
//
// /* length total (bytes) */
// rtcm->nbyte = rtcm->len+3;
//
// return 1;
// }