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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
|
/* gpsutils.c -- code shared between low-level and high-level interfaces
*
* This file is Copyright (c) 2010 by the GPSD project
* BSD terms apply: see the file COPYING in the distribution root for details.
*/
#include <stdio.h>
#include <time.h>
#include <sys/time.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "gpsd.h"
#ifdef USE_QT
#include <QDateTime>
#include <QStringList>
#endif
#define MONTHSPERYEAR 12 /* months per calendar year */
void gps_clear_fix( /*@out@*/ struct gps_fix_t *fixp)
/* stuff a fix structure with recognizable out-of-band values */
{
fixp->time = NAN;
fixp->mode = MODE_NOT_SEEN;
fixp->latitude = fixp->longitude = NAN;
fixp->track = NAN;
fixp->speed = NAN;
fixp->climb = NAN;
fixp->altitude = NAN;
fixp->ept = NAN;
fixp->epx = NAN;
fixp->epy = NAN;
fixp->epv = NAN;
fixp->epd = NAN;
fixp->eps = NAN;
fixp->epc = NAN;
}
void gps_merge_fix( /*@ out @*/ struct gps_fix_t *to,
gps_mask_t transfer,
/*@ in @*/ struct gps_fix_t *from)
/* merge new data into an old fix */
{
if ((NULL == to) || (NULL == from))
return;
if ((transfer & TIME_SET) != 0)
to->time = from->time;
if ((transfer & LATLON_SET) != 0) {
to->latitude = from->latitude;
to->longitude = from->longitude;
}
if ((transfer & MODE_SET) != 0)
to->mode = from->mode;
if ((transfer & ALTITUDE_SET) != 0)
to->altitude = from->altitude;
if ((transfer & TRACK_SET) != 0)
to->track = from->track;
if ((transfer & SPEED_SET) != 0)
to->speed = from->speed;
if ((transfer & CLIMB_SET) != 0)
to->climb = from->climb;
if ((transfer & TIMERR_SET) != 0)
to->ept = from->ept;
if ((transfer & HERR_SET) != 0) {
to->epx = from->epx;
to->epy = from->epy;
}
if ((transfer & VERR_SET) != 0)
to->epv = from->epv;
if ((transfer & SPEEDERR_SET) != 0)
to->eps = from->eps;
}
timestamp_t timestamp(void)
{
struct timeval tv;
(void)gettimeofday(&tv, NULL);
return (timestamp_t)(tv.tv_sec + tv.tv_usec * 1e-6);
}
time_t mkgmtime(register struct tm * t)
/* struct tm to seconds since Unix epoch */
{
register int year;
register time_t result;
static const int cumdays[MONTHSPERYEAR] =
{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
/*@ +matchanyintegral @*/
year = 1900 + t->tm_year + t->tm_mon / MONTHSPERYEAR;
result = (year - 1970) * 365 + cumdays[t->tm_mon % MONTHSPERYEAR];
result += (year - 1968) / 4;
result -= (year - 1900) / 100;
result += (year - 1600) / 400;
if ((year % 4) == 0 && ((year % 100) != 0 || (year % 400) == 0) &&
(t->tm_mon % MONTHSPERYEAR) < 2)
result--;
result += t->tm_mday - 1;
result *= 24;
result += t->tm_hour;
result *= 60;
result += t->tm_min;
result *= 60;
result += t->tm_sec;
/*@ -matchanyintegral @*/
return (result);
}
timestamp_t iso8601_to_unix( /*@in@*/ char *isotime)
/* ISO8601 UTC to Unix UTC */
{
#ifndef USE_QT
char *dp = NULL;
double usec;
struct tm tm;
/*@i1@*/ dp = strptime(isotime, "%Y-%m-%dT%H:%M:%S", &tm);
if (dp != NULL && *dp == '.')
usec = strtod(dp, NULL);
else
usec = 0;
return (timestamp_t)mkgmtime(&tm) + usec;
#else
double usec = 0;
QString t(isotime);
QDateTime d = QDateTime::fromString(isotime, Qt::ISODate);
QStringList sl = t.split(".");
if (sl.size() > 1)
usec = sl[1].toInt() / pow(10., (double)sl[1].size());
return (timestamp_t)(d.toTime_t() + usec);
#endif
}
/* *INDENT-OFF* */
/*@observer@*/char *unix_to_iso8601(timestamp_t fixtime, /*@ out @*/
char isotime[], size_t len)
/* Unix UTC time to ISO8601, no timezone adjustment */
/* example: 2007-12-11T23:38:51.033Z */
{
struct tm when;
double integral, fractional;
time_t intfixtime;
char timestr[30];
char fractstr[10];
fractional = modf(fixtime, &integral);
intfixtime = (time_t) integral;
(void)gmtime_r(&intfixtime, &when);
(void)strftime(timestr, sizeof(timestr), "%Y-%m-%dT%H:%M:%S", &when);
/*
* Do not mess casually with the number of decimal digits in the
* format! Most GPSes report over serial links at 0.01s or 0.001s
* precision.
*/
(void)snprintf(fractstr, sizeof(fractstr), "%.3f", fractional);
/* add fractional part, ignore leading 0; "0.2" -> ".2" */
/*@i2@*/(void)snprintf(isotime, len, "%s%sZ",timestr, strchr(fractstr,'.'));
return isotime;
}
/* *INDENT-ON* */
#define Deg2Rad(n) ((n) * DEG_2_RAD)
/* Distance in meters between two points specified in degrees, optionally
with initial and final bearings. */
/*@-mustdefine@*/
double earth_distance_and_bearings(double lat1, double lon1, double lat2, double lon2, double *ib, double *fb)
{
/*
* this is a translation of the javascript implementation of the
* Vincenty distance formula by Chris Veness. See
* http://www.movable-type.co.uk/scripts/latlong-vincenty.html
*/
double a, b, f; // WGS-84 ellipsoid params
double L, L_P, U1, U2, s_U1, c_U1, s_U2, c_U2;
double uSq, A, B, d_S, lambda;
double s_L, c_L, s_S, C;
double c_S, S, s_A, c_SqA, c_2SM;
int i = 100;
a = WGS84A;
b = WGS84B;
f = 1 / WGS84F;
L = Deg2Rad(lon2 - lon1);
U1 = atan((1 - f) * tan(Deg2Rad(lat1)));
U2 = atan((1 - f) * tan(Deg2Rad(lat2)));
s_U1 = sin(U1);
c_U1 = cos(U1);
s_U2 = sin(U2);
c_U2 = cos(U2);
lambda = L;
do {
s_L = sin(lambda);
c_L = cos(lambda);
s_S = sqrt((c_U2 * s_L) * (c_U2 * s_L) +
(c_U1 * s_U2 - s_U1 * c_U2 * c_L) *
(c_U1 * s_U2 - s_U1 * c_U2 * c_L));
if (s_S == 0)
return 0;
c_S = s_U1 * s_U2 + c_U1 * c_U2 * c_L;
S = atan2(s_S, c_S);
s_A = c_U1 * c_U2 * s_L / s_S;
c_SqA = 1 - s_A * s_A;
c_2SM = c_S - 2 * s_U1 * s_U2 / c_SqA;
if (isnan(c_2SM))
c_2SM = 0;
C = f / 16 * c_SqA * (4 + f * (4 - 3 * c_SqA));
L_P = lambda;
lambda = L + (1 - C) * f * s_A *
(S + C * s_S * (c_2SM + C * c_S * (2 * c_2SM * c_2SM - 1)));
} while ((fabs(lambda - L_P) > 1.0e-12) && (--i > 0));
if (i == 0)
return NAN; // formula failed to converge
uSq = c_SqA * ((a * a) - (b * b)) / (b * b);
A = 1 + uSq / 16384 * (4096 + uSq * (-768 + uSq * (320 - 175 * uSq)));
B = uSq / 1024 * (256 + uSq * (-128 + uSq * (74 - 47 * uSq)));
d_S = B * s_S * (c_2SM + B / 4 *
(c_S * (-1 + 2 * c_2SM * c_2SM) - B / 6 * c_2SM *
(-3 + 4 * s_S * s_S) * (-3 + 4 * c_2SM * c_2SM)));
if (ib != NULL)
*ib = atan2(c_U2 * sin(lambda), c_U1 * s_U2 - s_U1 * c_U2 * cos(lambda));
if (fb != NULL)
*fb = atan2(c_U1 * sin(lambda), c_U1 * s_U2 * cos(lambda) - s_U1 * c_U2);
return (WGS84B * A * (S - d_S));
}
/*@+mustdefine@*/
/* Distance in meters between two points specified in degrees. */
double earth_distance(double lat1, double lon1, double lat2, double lon2)
{
return earth_distance_and_bearings(lat1, lon1, lat2, lon2, NULL, NULL);
}
|
