ugps: add quality measurement parameters
[project/ugps.git] / nmea.c
diff --git a/nmea.c b/nmea.c
index 8df77929f422dfe17d3625da8d8c6f622b899867..195753e80773d5feb940d7080fd8c3851ecf184c 100644 (file)
--- a/nmea.c
+++ b/nmea.c
@@ -52,8 +52,9 @@ struct nmea_param {
 } nmea_params[MAX_NMEA_PARAM];
 
 static int nmea_bad_time;
-char longitude[33] = { 0 }, latitude[33] = { 0 }, course[17] = { 0 }, speed[17] = { 0 }, elevation[17] = { 0 };
+char longitude[33] = { 0 }, latitude[33] = { 0 }, course[17] = { 0 }, speed[17] = { 0 }, elevation[17] = { 0 }, satellites[3] = { 0 }, hdop[5] = { 0 };
 int gps_valid = 0;
+char gps_fields = 0;
 
 static void
 nmea_txt_cb(void)
@@ -66,11 +67,68 @@ nmea_txt_cb(void)
        DEBUG(3, "%s: %s\n", ids[nmea_params[3].num], nmea_params[4].str);
 }
 
+static void
+do_adjust_clock(struct tm *tm)
+{
+       char tmp[256];
+
+       strftime(tmp, 256, "%Y-%m-%dT%H:%M:%S", tm);
+       DEBUG(3, "date: %s UTC\n", tmp);
+
+       if (adjust_clock) {
+               time_t sec = timegm(tm);
+               struct timeval cur;
+
+               gettimeofday(&cur, NULL);
+
+               if ((sec < 0) || (llabs(cur.tv_sec - sec) > MAX_TIME_OFFSET)) {
+                       struct timeval tv = { 0 };
+                       tv.tv_sec = sec;
+                       if (++nmea_bad_time > MAX_BAD_TIME) {
+                               LOG("system time differs from GPS time by more than %d seconds. Using %s UTC as the new time\n", MAX_TIME_OFFSET, tmp);
+                               /* only set datetime if specified by command line argument! */
+                               settimeofday(&tv, NULL);
+                       }
+               } else {
+                       nmea_bad_time = 0;
+               }
+       }
+}
+
+static void
+parse_gps_coords(char *latstr, char *vhem, char *lonstr, char *hhem)
+{
+       float minutes;
+       float degrees;
+       float lat = strtof(latstr, NULL);
+       float lon = strtof(lonstr, NULL);
+
+       degrees = floor(lat / 100.0);
+       minutes = lat - (degrees * 100.0);
+       lat = degrees + minutes / 60.0;
+
+       degrees = floor(lon / 100.0);
+       minutes = lon - (degrees * 100.0);
+       lon = degrees + minutes / 60.0;
+
+       if (*vhem == 'S')
+               lat *= -1.0;
+       if (*hhem == 'W')
+               lon *= -1.0;
+
+       snprintf(latitude, sizeof(latitude), "%f", lat);
+       snprintf(longitude, sizeof(longitude), "%f", lon);
+
+       DEBUG(3, "position: %s %s\n", latitude, longitude);
+       gps_fields |= GPS_FIELD_LAT | GPS_FIELD_LON;
+
+       gps_timestamp();
+}
+
 static void
 nmea_rmc_cb(void)
 {
        struct tm tm;
-       char tmp[256];
 
        if (*nmea_params[2].str != 'A') {
                gps_valid = 0;
@@ -98,57 +156,65 @@ nmea_rmc_cb(void)
                tm.tm_year += 100; /* year starts with 1900 */
                tm.tm_mon -= 1; /* month starts with 0 */
 
-               strftime(tmp, 256, "%Y-%m-%dT%H:%M:%S", &tm);
-               DEBUG(3, "date: %s UTC\n", tmp);
-
-               if (adjust_clock) {
-                       time_t sec = timegm(&tm);
-                       struct timeval cur;
-
-                       gettimeofday(&cur, NULL);
-
-                       if ((sec < 0) || (abs(cur.tv_sec - sec) > MAX_TIME_OFFSET)) {
-                               struct timeval tv = { 0 };
-                               tv.tv_sec = sec;
-                               if (++nmea_bad_time > MAX_BAD_TIME) {
-                                       LOG("system time differs from GPS time by more than %d seconds. Using %s UTC as the new time\n", MAX_TIME_OFFSET, tmp);
-                                       /* only set datetime if specified by command line argument! */
-                                       settimeofday(&tv, NULL);
-                               }
-                       } else {
-                               nmea_bad_time = 0;
-                       }
-               }
+               do_adjust_clock(&tm);
        }
 
        if (strlen(nmea_params[3].str) < 9 || strlen(nmea_params[5].str) < 10) {
                ERROR("lat/lng have invalid string length %zu<9, %zu<10\n",
                       strlen(nmea_params[3].str), strlen(nmea_params[5].str));
        } else {
-               float minutes;
-               float degrees;
-               float lat = strtof(nmea_params[3].str, NULL);
-               float lon = strtof(nmea_params[5].str, NULL);
+               parse_gps_coords(nmea_params[3].str, nmea_params[4].str, nmea_params[5].str, nmea_params[6].str);
+       }
+}
+
+static void
+nmea_zda_cb(void)
+{
+       struct tm tm;
+
+       if (!gps_valid)
+               return;
 
-               degrees = floor(lat / 100.0);
-               minutes = lat - (degrees * 100.0);
-               lat = degrees + minutes / 60.0;
+       memset(&tm, 0, sizeof(tm));
+       tm.tm_isdst = 1;
+
+       if (sscanf(nmea_params[1].str, "%02d%02d%02d",
+               &tm.tm_hour, &tm.tm_min, &tm.tm_sec) != 3) {
+               ERROR("failed to parse time '%s'\n", nmea_params[1].str);
+               return;
+       }
+
+       if ((sscanf(nmea_params[2].str, "%02d", &tm.tm_mday) != 1) ||
+           (sscanf(nmea_params[3].str, "%02d", &tm.tm_mon) != 1) ||
+           (sscanf(nmea_params[4].str, "%04d", &tm.tm_year) != 1)) {
+               ERROR("failed to parse time '%s,%s,%s'\n",
+                       nmea_params[2].str, nmea_params[3].str, nmea_params[4].str);
+               return;
+       }
 
-               degrees = floor(lon / 100.0);
-               minutes = lon - (degrees * 100.0);
-               lon = degrees + minutes / 60.0;
+       if (tm.tm_year == 0) {
+               DEBUG(4, "waiting for valid date\n");
+               return;
+       }
 
-               if (*nmea_params[4].str == 'S')
-                       lat *= -1.0;
-               if (*nmea_params[6].str == 'W')
-                       lon *= -1.0;
+       tm.tm_mon -= 1; /* month starts with 0 */
+       tm.tm_year -= 1900; /* full 4-digit year, tm expects years till 1900 */
 
-               snprintf(latitude, sizeof(latitude), "%f", lat);
-               snprintf(longitude, sizeof(longitude), "%f", lon);
+       do_adjust_clock(&tm);
+}
 
-               DEBUG(3, "position: %s %s\n", latitude, longitude);
-               gps_timestamp();
+static void
+nmea_gll_cb(void)
+{
+       if (*nmea_params[6].str != 'A') {
+               gps_valid = 0;
+               DEBUG(4, "waiting for valid signal\n");
+               return;
        }
+
+       gps_valid = 1;
+
+       parse_gps_coords(nmea_params[1].str, nmea_params[2].str, nmea_params[3].str, nmea_params[4].str);
 }
 
 static void
@@ -156,7 +222,12 @@ nmea_gga_cb(void)
 {
        if (!gps_valid)
                return;
+       strncpy(satellites, nmea_params[7].str, sizeof(satellites));
+       strncpy(hdop, nmea_params[8].str, sizeof(hdop));
        strncpy(elevation, nmea_params[9].str, sizeof(elevation));
+       gps_fields |= GPS_FIELD_SAT | GPS_FIELD_HDP | GPS_FIELD_ALT;
+       DEBUG(4, "satellites: %s\n", satellites);
+       DEBUG(4, "HDOP: %s\n", hdop);
        DEBUG(4, "height: %s\n", elevation);
 }
 
@@ -167,6 +238,7 @@ nmea_vtg_cb(void)
                return;
        strncpy(course, nmea_params[1].str, sizeof(course));
        strncpy(speed, nmea_params[7].str, sizeof(speed));
+       gps_fields |= GPS_FIELD_COG | GPS_FIELD_SPD;
        DEBUG(4, "course: %s\n", course);
        DEBUG(4, "speed: %s\n", speed);
 }
@@ -188,10 +260,18 @@ static struct nmea_msg {
                .msg = "GGA",
                .cnt = 14,
                .handler = nmea_gga_cb,
+       }, {
+               .msg = "GLL",
+               .cnt = 7,
+               .handler = nmea_gll_cb,
        }, {
                .msg = "VTG",
                .cnt = 9,
                .handler = nmea_vtg_cb,
+       }, {
+               .msg = "ZDA",
+               .cnt = 5,
+               .handler = nmea_zda_cb,
        },
 };
 
@@ -240,7 +320,8 @@ nmea_process(char *a)
        int cnt;
        unsigned int i;
 
-       if (strncmp(a, "$GP", 3))
+       if (strncmp(a, "$GP", 3) &&
+           strncmp(a, "$GN", 3))
                return;
 
        a++;
@@ -260,7 +341,8 @@ nmea_process(char *a)
        }
 
        for (i = 0; i < ARRAY_SIZE(nmea_msgs); i++) {
-               if (strcmp(nmea_params[0].str, nmea_msgs[i].msg))
+               if (strcmp(nmea_params[0].str, nmea_msgs[i].msg) &&
+                   strcmp(nmea_params[3].str, nmea_msgs[i].msg))
                        continue;
                if (nmea_msgs[i].cnt <= cnt)
                        nmea_msgs[i].handler();