1 files changed, 234 insertions, 0 deletions
diff --git a/src/common/includes/GPS/minmea.h b/src/common/includes/GPS/minmea.h
new file mode 100644
index 0000000..6d7fe18
--- /dev/null
+++ b/src/common/includes/GPS/minmea.h
@@ -0,0 +1,234 @@
+/*
+ * Copyright © 2014 Kosma Moczek <kosma@cloudyourcar.com>
+ * This program is free software. It comes without any warranty, to the extent
+ * permitted by applicable law. You can redistribute it and/or modify it under
+ * the terms of the Do What The Fuck You Want To Public License, Version 2, as
+ * published by Sam Hocevar. See the COPYING file for more details.
+ */
+
+#ifndef MINMEA_H
+#define MINMEA_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <time.h>
+#include <math.h>
+
+#define MINMEA_MAX_LENGTH 80
+
+enum minmea_sentence_id {
+    MINMEA_INVALID = -1,
+    MINMEA_UNKNOWN = 0,
+    MINMEA_SENTENCE_RMC,
+    MINMEA_SENTENCE_GGA,
+    MINMEA_SENTENCE_GSA,
+    MINMEA_SENTENCE_GLL,
+    MINMEA_SENTENCE_GST,
+    MINMEA_SENTENCE_GSV,
+};
+
+struct minmea_float {
+    int_least32_t value;
+    int_least32_t scale;
+};
+
+struct minmea_date {
+    int day;
+    int month;
+    int year;
+};
+
+struct minmea_time {
+    int hours;
+    int minutes;
+    int seconds;
+    int microseconds;
+};
+
+struct minmea_sentence_rmc {
+    struct minmea_time time;
+    bool valid;
+    struct minmea_float latitude;
+    struct minmea_float longitude;
+    struct minmea_float speed;
+    struct minmea_float course;
+    struct minmea_date date;
+    struct minmea_float variation;
+};
+
+struct minmea_sentence_gga {
+    struct minmea_time time;
+    struct minmea_float latitude;
+    struct minmea_float longitude;
+    int fix_quality;
+    int satellites_tracked;
+    struct minmea_float hdop;
+    struct minmea_float altitude; char altitude_units;
+    struct minmea_float height; char height_units;
+    int dgps_age;
+};
+
+enum minmea_gll_status {
+    MINMEA_GLL_STATUS_DATA_VALID = 'A',
+    MINMEA_GLL_STATUS_DATA_NOT_VALID = 'V',
+};
+
+enum minmea_gll_mode {
+    MINMEA_GLL_MODE_AUTONOMOUS = 'A',
+    MINMEA_GLL_MODE_DPGS = 'D',
+    MINMEA_GLL_MODE_DR = 'E',
+};
+
+struct minmea_sentence_gll {
+    struct minmea_float latitude;
+    struct minmea_float longitude;
+    struct minmea_time time;
+    char status;
+    char mode;
+};
+
+struct minmea_sentence_gst {
+    struct minmea_time time;
+    struct minmea_float rms_deviation;
+    struct minmea_float semi_major_deviation;
+    struct minmea_float semi_minor_deviation;
+    struct minmea_float semi_major_orientation;
+    struct minmea_float latitude_error_deviation;
+    struct minmea_float longitude_error_deviation;
+    struct minmea_float altitude_error_deviation;
+};
+
+enum minmea_gsa_mode {
+    MINMEA_GPGSA_MODE_AUTO = 'A',
+    MINMEA_GPGSA_MODE_FORCED = 'M',
+};
+
+enum minmea_gsa_fix_type {
+    MINMEA_GPGSA_FIX_NONE = 1,
+    MINMEA_GPGSA_FIX_2D = 2,
+    MINMEA_GPGSA_FIX_3D = 3,
+};
+
+struct minmea_sentence_gsa {
+    char mode;
+    int fix_type;
+    int sats[12];
+    struct minmea_float pdop;
+    struct minmea_float hdop;
+    struct minmea_float vdop;
+};
+
+struct minmea_sat_info {
+    int nr;
+    int elevation;
+    int azimuth;
+    int snr;
+};
+
+struct minmea_sentence_gsv {
+    int total_msgs;
+    int msg_nr;
+    int total_sats;
+    struct minmea_sat_info sats[4];
+};
+
+/**
+ * Calculate raw sentence checksum. Does not check sentence integrity.
+ */
+uint8_t minmea_checksum(const char *sentence);
+
+/**
+ * Check sentence validity and checksum. Returns true for valid sentences.
+ */
+bool minmea_check(const char *sentence, bool strict);
+
+/**
+ * Determine talker identifier.
+ */
+bool minmea_talker_id(char talker[3], const char *sentence);
+
+/**
+ * Determine sentence identifier.
+ */
+enum minmea_sentence_id minmea_sentence_id(const char *sentence, bool strict);
+
+/**
+ * Scanf-like processor for NMEA sentences. Supports the following formats:
+ * c - single character (char *)
+ * d - direction, returned as 1/-1, default 0 (int *)
+ * f - fractional, returned as value + scale (int *, int *)
+ * i - decimal, default zero (int *)
+ * s - string (char *)
+ * t - talker identifier and type (char *)
+ * T - date/time stamp (int *, int *, int *)
+ * Returns true on success. See library source code for details.
+ */
+bool minmea_scan(const char *sentence, const char *format, ...);
+
+/*
+ * Parse a specific type of sentence. Return true on success.
+ */
+bool minmea_parse_rmc(struct minmea_sentence_rmc *frame, const char *sentence);
+bool minmea_parse_gga(struct minmea_sentence_gga *frame, const char *sentence);
+bool minmea_parse_gsa(struct minmea_sentence_gsa *frame, const char *sentence);
+bool minmea_parse_gll(struct minmea_sentence_gll *frame, const char *sentence);
+bool minmea_parse_gst(struct minmea_sentence_gst *frame, const char *sentence);
+bool minmea_parse_gsv(struct minmea_sentence_gsv *frame, const char *sentence);
+
+/**
+ * Convert GPS UTC date/time representation to a UNIX timestamp.
+ */
+int minmea_gettime(struct timespec *ts, const struct minmea_date *date, const struct minmea_time *time_);
+
+/**
+ * Rescale a fixed-point value to a different scale. Rounds towards zero.
+ */
+static inline int_least32_t minmea_rescale(struct minmea_float *f, int_least32_t new_scale)
+{
+    if (f->scale == 0)
+        return 0;
+    if (f->scale == new_scale)
+        return f->value;
+    if (f->scale > new_scale)
+        return (f->value + ((f->value > 0) - (f->value < 0)) * f->scale/new_scale/2) / (f->scale/new_scale);
+    else
+        return f->value * (new_scale/f->scale);
+}
+
+/**
+ * Convert a fixed-point value to a floating-point value.
+ * Returns NaN for "unknown" values.
+ */
+static inline float minmea_tofloat(struct minmea_float *f)
+{
+    if (f->scale == 0)
+        return NAN;
+    return (float) f->value / (float) f->scale;
+}
+
+/**
+ * Convert a raw coordinate to a floating point DD.DDD... value.
+ * Returns NaN for "unknown" values.
+ */
+static inline float minmea_tocoord(struct minmea_float *f)
+{
+    if (f->scale == 0)
+        return NAN;
+    int_least32_t degrees = f->value / (f->scale * 100);
+    int_least32_t minutes = f->value % (f->scale * 100);
+    return (float) degrees + (float) minutes / (60 * f->scale);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MINMEA_H */
+
+/* vim: set ts=4 sw=4 et: */