summaryrefslogtreecommitdiff
path: root/gpsdclient.c
blob: 4e99123268c60dd0bdac86a99ea21084dc826f10 (plain)
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
/*
 * gpsdclient.c -- support functions for GPSD clients
 *
 * This file is Copyright (c) 2010 by the GPSD project
 * BSD terms apply: see the file COPYING in the distribution root for details.
 */
#include <sys/time.h>
#include <stdio.h>
#ifndef S_SPLINT_S
#include <unistd.h>
#endif /* S_SPLINT_S */
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdarg.h>
#include <math.h>
#include <assert.h>

#include "gpsd_config.h"
#include "gps.h"
#include "gpsdclient.h"

#ifdef HAVE_SETLOCALE
#include <locale.h>
#endif

/* convert double degrees to a static string and return a pointer to it
 *
 * deg_str_type:
 *   	deg_dd     : return DD.dddddd
 *      deg_ddmm   : return DD MM.mmmm'
 *      deg_ddmmss : return DD MM' SS.sss"
 *
 */
/*@observer@*/ char *deg_to_str(enum deg_str_type type, double f)
{
    static char str[40];
    int dsec, sec, deg, min;
    long frac_deg;
    double fdsec, fsec, fdeg, fmin;

    if (f < 0 || f > 360) {
	(void)strlcpy(str, "nan", 40);
	return str;
    }

    fmin = modf(f, &fdeg);
    deg = (int)fdeg;
    frac_deg = (long)(fmin * 1000000);

    if (deg_dd == type) {
	/* DD.dddddd */
	(void)snprintf(str, sizeof(str), "%3d.%06ld", deg, frac_deg);
	return str;
    }
    fsec = modf(fmin * 60, &fmin);
    min = (int)fmin;
    sec = (int)(fsec * 10000.0);

    if (deg_ddmm == type) {
	/* DD MM.mmmm */
	(void)snprintf(str, sizeof(str), "%3d %02d.%04d'", deg, min, sec);
	return str;
    }
    /* else DD MM SS.sss */
    fdsec = modf(fsec * 60, &fsec);
    sec = (int)fsec;
    dsec = (int)(fdsec * 1000.0);
    (void)snprintf(str, sizeof(str), "%3d %02d' %02d.%03d\"", deg, min, sec,
		   dsec);

    return str;
}

/* 
 * check the environment to determine proper GPS units
 *
 * clients should only call this if no user preference is specified on 
 * the command line or via X resources.
 *
 * return imperial    - Use miles/feet
 *        nautical    - Use knots/feet
 *        metric      - Use km/meters
 *        unspecified - use compiled default
 * 
 * In order check these environment vars:
 *    GPSD_UNITS one of: 
 *            	imperial   = miles/feet
 *              nautical   = knots/feet
 *              metric     = km/meters
 *    LC_MEASUREMENT
 *		en_US      = miles/feet
 *              C          = miles/feet
 *              POSIX      = miles/feet
 *              [other]    = km/meters
 *    LANG
 *		en_US      = miles/feet
 *              C          = miles/feet
 *              POSIX      = miles/feet
 *              [other]    = km/meters
 *
 * if none found then return compiled in default
 */
enum unit gpsd_units(void)
{
    char *envu = NULL;

#ifdef HAVE_SETLOCALE
    (void)setlocale(LC_NUMERIC, "C");
#endif
    if ((envu = getenv("GPSD_UNITS")) != NULL && *envu != '\0') {
	if (0 == strcasecmp(envu, "imperial")) {
	    return imperial;
	}
	if (0 == strcasecmp(envu, "nautical")) {
	    return nautical;
	}
	if (0 == strcasecmp(envu, "metric")) {
	    return metric;
	}
	/* unrecognized, ignore it */
    }
    if (((envu = getenv("LC_MEASUREMENT")) != NULL && *envu != '\0')
	|| ((envu = getenv("LANG")) != NULL && *envu != '\0')) {
	if (strncasecmp(envu, "en_US", 5) == 0
	    || strcasecmp(envu, "C") == 0 || strcasecmp(envu, "POSIX") == 0) {
	    return imperial;
	}
	/* Other, must be metric */
	return metric;
    }
    /* TODO: allow a compile time default here */
    return unspecified;
}

/*@ -observertrans -statictrans -mustfreeonly -branchstate -kepttrans @*/
void gpsd_source_spec(const char *arg, struct fixsource_t *source)
/* standard parsing of a GPS data source spec */
{
    source->server = "localhost";
    source->port = DEFAULT_GPSD_PORT;
    source->device = NULL;

    /*@-usedef@ Sigh, splint is buggy */
    if (arg != NULL) {
	char *colon1, *skipto, *rbrk;
	source->spec = strdup(arg);
	assert(source->spec != NULL);

	skipto = source->spec;
	if (*skipto == '[' && (rbrk = strchr(skipto, ']')) != NULL) {
	    skipto = rbrk;
	}
	colon1 = strchr(skipto, ':');

	if (colon1 != NULL) {
	    char *colon2;
	    *colon1 = '\0';
	    if (colon1 != source->spec) {
		source->server = source->spec;
	    }
	    source->port = colon1 + 1;
	    colon2 = strchr(source->port, ':');
	    if (colon2 != NULL) {
		*colon2 = '\0';
		source->device = colon2 + 1;
	    }
	} else if (strchr(source->spec, '/') != NULL) {
	    source->device = source->spec;
	} else {
	    source->server = source->spec;
	}
    }

    /*@-modobserver@*/
    if (*source->server == '[') {
	char *rbrk = strchr(source->server, ']');
	++source->server;
	if (rbrk != NULL)
	    *rbrk = '\0';
    }
    /*@+modobserver@*/
    /*@+usedef@*/
}

/*@ +observertrans -statictrans +mustfreeonly +branchstate +kepttrans @*/

/* gpsclient.c ends here */