Change common/ folder structure

1 files changed, 597 insertions, 0 deletions

diff --git a/src/common/GPS/minmea.c b/src/common/GPS/minmea.c
new file mode 100644
index 0000000..4d4aeb8
--- /dev/null
+++ b/src/common/GPS/minmea.c
@@ -0,0 +1,597 @@
+/*
+ * 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.
+ */
+
+// We are lacking timegm, but we only handle UTC and use mktime instead. See
+// https://github.com/cloudyourcar/minmea-t/ README.md
+#define timegm mktime
+
+#include "GPS/minmea.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <stdarg.h>
+
+#define boolstr(s) ((s) ? "true" : "false")
+
+static int hex2int(char c)
+{
+    if (c >= '0' && c <= '9')
+        return c - '0';
+    if (c >= 'A' && c <= 'F')
+        return c - 'A' + 10;
+    if (c >= 'a' && c <= 'f')
+        return c - 'a' + 10;
+    return -1;
+}
+
+uint8_t minmea_checksum(const char *sentence)
+{
+    // Support senteces with or without the starting dollar sign.
+    if (*sentence == '$')
+        sentence++;
+
+    uint8_t checksum = 0x00;
+
+    // The optional checksum is an XOR of all bytes between "$" and "*".
+    while (*sentence && *sentence != '*')
+        checksum ^= *sentence++;
+
+    return checksum;
+}
+
+bool minmea_check(const char *sentence, bool strict)
+{
+    uint8_t checksum = 0x00;
+
+    // Sequence length is limited.
+    if (strlen(sentence) > MINMEA_MAX_LENGTH + 3)
+        return false;
+
+    // A valid sentence starts with "$".
+    if (*sentence++ != '$')
+        return false;
+
+    // The optional checksum is an XOR of all bytes between "$" and "*".
+    while (*sentence && *sentence != '*' && isprint((unsigned char) *sentence))
+        checksum ^= *sentence++;
+
+    // If checksum is present...
+    if (*sentence == '*') {
+        // Extract checksum.
+        sentence++;
+        int upper = hex2int(*sentence++);
+        if (upper == -1)
+            return false;
+        int lower = hex2int(*sentence++);
+        if (lower == -1)
+            return false;
+        int expected = upper << 4 | lower;
+
+        // Check for checksum mismatch.
+        if (checksum != expected)
+            return false;
+    } else if (strict) {
+        // Discard non-checksummed frames in strict mode.
+        return false;
+    }
+
+    // The only stuff allowed at this point is a newline.
+    if (*sentence && strcmp(sentence, "\n") && strcmp(sentence, "\r\n"))
+        return false;
+
+    return true;
+}
+
+static inline bool minmea_isfield(char c) {
+    return isprint((unsigned char) c) && c != ',' && c != '*';
+}
+
+bool minmea_scan(const char *sentence, const char *format, ...)
+{
+    bool result = false;
+    bool optional = false;
+    va_list ap;
+    va_start(ap, format);
+
+    const char *field = sentence;
+#define next_field() \
+    do { \
+        /* Progress to the next field. */ \
+        while (minmea_isfield(*sentence)) \
+            sentence++; \
+        /* Make sure there is a field there. */ \
+        if (*sentence == ',') { \
+            sentence++; \
+            field = sentence; \
+        } else { \
+            field = NULL; \
+        } \
+    } while (0)
+
+    while (*format) {
+        char type = *format++;
+
+        if (type == ';') {
+            // All further fields are optional.
+            optional = true;
+            continue;
+        }
+
+        if (!field && !optional) {
+            // Field requested but we ran out if input. Bail out.
+            goto parse_error;
+        }
+
+        switch (type) {
+            case 'c': { // Single character field (char).
+                char value = '\0';
+
+                if (field && minmea_isfield(*field))
+                    value = *field;
+
+                *va_arg(ap, char *) = value;
+            } break;
+
+            case 'd': { // Single character direction field (int).
+                int value = 0;
+
+                if (field && minmea_isfield(*field)) {
+                    switch (*field) {
+                        case 'N':
+                        case 'E':
+                            value = 1;
+                            break;
+                        case 'S':
+                        case 'W':
+                            value = -1;
+                            break;
+                        default:
+                            goto parse_error;
+                    }
+                }
+
+                *va_arg(ap, int *) = value;
+            } break;
+
+            case 'f': { // Fractional value with scale (struct minmea_float).
+                int sign = 0;
+                int_least32_t value = -1;
+                int_least32_t scale = 0;
+
+                if (field) {
+                    while (minmea_isfield(*field)) {
+                        if (*field == '+' && !sign && value == -1) {
+                            sign = 1;
+                        } else if (*field == '-' && !sign && value == -1) {
+                            sign = -1;
+                        } else if (isdigit((unsigned char) *field)) {
+                            int digit = *field - '0';
+                            if (value == -1)
+                                value = 0;
+                            if (value > (INT_LEAST32_MAX-digit) / 10) {
+                                /* we ran out of bits, what do we do? */
+                                if (scale) {
+                                    /* truncate extra precision */
+                                    break;
+                                } else {
+                                    /* integer overflow. bail out. */
+                                    goto parse_error;
+                                }
+                            }
+                            value = (10 * value) + digit;
+                            if (scale)
+                                scale *= 10;
+                        } else if (*field == '.' && scale == 0) {
+                            scale = 1;
+                        } else if (*field == ' ') {
+                            /* Allow spaces at the start of the field. Not NMEA
+                             * conformant, but some modules do this. */
+                            if (sign != 0 || value != -1 || scale != 0)
+                                goto parse_error;
+                        } else {
+                            goto parse_error;
+                        }
+                        field++;
+                    }
+                }
+
+                if ((sign || scale) && value == -1)
+                    goto parse_error;
+
+                if (value == -1) {
+                    /* No digits were scanned. */
+                    value = 0;
+                    scale = 0;
+                } else if (scale == 0) {
+                    /* No decimal point. */
+                    scale = 1;
+                }
+                if (sign)
+                    value *= sign;
+
+                *va_arg(ap, struct minmea_float *) = (struct minmea_float) {value, scale};
+            } break;
+
+            case 'i': { // Integer value, default 0 (int).
+                int value = 0;
+
+                if (field) {
+                    char *endptr;
+                    value = strtol(field, &endptr, 10);
+                    if (minmea_isfield(*endptr))
+                        goto parse_error;
+                }
+
+                *va_arg(ap, int *) = value;
+            } break;
+
+            case 's': { // String value (char *).
+                char *buf = va_arg(ap, char *);
+
+                if (field) {
+                    while (minmea_isfield(*field))
+                        *buf++ = *field++;
+                }
+
+                *buf = '\0';
+            } break;
+
+            case 't': { // NMEA talker+sentence identifier (char *).
+                // This field is always mandatory.
+                if (!field)
+                    goto parse_error;
+
+                if (field[0] != '$')
+                    goto parse_error;
+                for (int f=0; f<5; f++)
+                    if (!minmea_isfield(field[1+f]))
+                        goto parse_error;
+
+                char *buf = va_arg(ap, char *);
+                memcpy(buf, field+1, 5);
+                buf[5] = '\0';
+            } break;
+
+            case 'D': { // Date (int, int, int), -1 if empty.
+                struct minmea_date *date = va_arg(ap, struct minmea_date *);
+
+                int d = -1, m = -1, y = -1;
+
+                if (field && minmea_isfield(*field)) {
+                    // Always six digits.
+                    for (int f=0; f<6; f++)
+                        if (!isdigit((unsigned char) field[f]))
+                            goto parse_error;
+
+                    d = strtol((char[]) {field[0], field[1], '\0'}, NULL, 10);
+                    m = strtol((char[]) {field[2], field[3], '\0'}, NULL, 10);
+                    y = strtol((char[]) {field[4], field[5], '\0'}, NULL, 10);
+                }
+
+                date->day = d;
+                date->month = m;
+                date->year = y;
+            } break;
+
+            case 'T': { // Time (int, int, int, int), -1 if empty.
+                struct minmea_time *time_ = va_arg(ap, struct minmea_time *);
+
+                int h = -1, i = -1, s = -1, u = -1;
+
+                if (field && minmea_isfield(*field)) {
+                    // Minimum required: integer time.
+                    for (int f=0; f<6; f++)
+                        if (!isdigit((unsigned char) field[f]))
+                            goto parse_error;
+
+                    h = strtol((char[]) {field[0], field[1], '\0'}, NULL, 10);
+                    i = strtol((char[]) {field[2], field[3], '\0'}, NULL, 10);
+                    s = strtol((char[]) {field[4], field[5], '\0'}, NULL, 10);
+                    field += 6;
+
+                    // Extra: fractional time. Saved as microseconds.
+                    if (*field++ == '.') {
+                        int value = 0;
+                        int scale = 1000000;
+                        while (isdigit((unsigned char) *field) && scale > 1) {
+                            value = (value * 10) + (*field++ - '0');
+                            scale /= 10;
+                        }
+                        u = value * scale;
+                    } else {
+                        u = 0;
+                    }
+                }
+
+                time_->hours = h;
+                time_->minutes = i;
+                time_->seconds = s;
+                time_->microseconds = u;
+            } break;
+
+            case '_': { // Ignore the field.
+            } break;
+
+            default: { // Unknown.
+                goto parse_error;
+            } break;
+        }
+
+        next_field();
+    }
+
+    result = true;
+
+parse_error:
+    va_end(ap);
+    return result;
+}
+
+bool minmea_talker_id(char talker[3], const char *sentence)
+{
+    char type[6];
+    if (!minmea_scan(sentence, "t", type))
+        return false;
+
+    talker[0] = type[0];
+    talker[1] = type[1];
+    talker[2] = '\0';
+
+    return true;
+}
+
+enum minmea_sentence_id minmea_sentence_id(const char *sentence, bool strict)
+{
+    if (!minmea_check(sentence, strict))
+        return MINMEA_INVALID;
+
+    char type[6];
+    if (!minmea_scan(sentence, "t", type))
+        return MINMEA_INVALID;
+
+    if (!strcmp(type+2, "RMC"))
+        return MINMEA_SENTENCE_RMC;
+    if (!strcmp(type+2, "GGA"))
+        return MINMEA_SENTENCE_GGA;
+    if (!strcmp(type+2, "GSA"))
+        return MINMEA_SENTENCE_GSA;
+    if (!strcmp(type+2, "GLL"))
+        return MINMEA_SENTENCE_GLL;
+    if (!strcmp(type+2, "GST"))
+        return MINMEA_SENTENCE_GST;
+    if (!strcmp(type+2, "GSV"))
+        return MINMEA_SENTENCE_GSV;
+    if (!strcmp(type+2, "TXT"))
+        return MINMEA_SENTENCE_TXT;
+
+    return MINMEA_UNKNOWN;
+}
+
+bool minmea_parse_rmc(struct minmea_sentence_rmc *frame, const char *sentence)
+{
+    // $GPRMC,081836,A,3751.65,S,14507.36,E,000.0,360.0,130998,011.3,E*62
+    char type[6];
+    char validity;
+    int latitude_direction;
+    int longitude_direction;
+    int variation_direction;
+    if (!minmea_scan(sentence, "tTcfdfdffDfd",
+            type,
+            &frame->time,
+            &validity,
+            &frame->latitude, &latitude_direction,
+            &frame->longitude, &longitude_direction,
+            &frame->speed,
+            &frame->course,
+            &frame->date,
+            &frame->variation, &variation_direction))
+        return false;
+    if (strcmp(type+2, "RMC"))
+        return false;
+
+    frame->valid = (validity == 'A');
+    frame->latitude.value *= latitude_direction;
+    frame->longitude.value *= longitude_direction;
+    frame->variation.value *= variation_direction;
+
+    return true;
+}
+
+bool minmea_parse_gga(struct minmea_sentence_gga *frame, const char *sentence)
+{
+    // $GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47
+    char type[6];
+    int latitude_direction;
+    int longitude_direction;
+
+    if (!minmea_scan(sentence, "tTfdfdiiffcfci_",
+            type,
+            &frame->time,
+            &frame->latitude, &latitude_direction,
+            &frame->longitude, &longitude_direction,
+            &frame->fix_quality,
+            &frame->satellites_tracked,
+            &frame->hdop,
+            &frame->altitude, &frame->altitude_units,
+            &frame->height, &frame->height_units,
+            &frame->dgps_age))
+        return false;
+    if (strcmp(type+2, "GGA"))
+        return false;
+
+    frame->latitude.value *= latitude_direction;
+    frame->longitude.value *= longitude_direction;
+
+    return true;
+}
+
+bool minmea_parse_gsa(struct minmea_sentence_gsa *frame, const char *sentence)
+{
+    // $GPGSA,A,3,04,05,,09,12,,,24,,,,,2.5,1.3,2.1*39
+    char type[6];
+
+    if (!minmea_scan(sentence, "tciiiiiiiiiiiiifff",
+            type,
+            &frame->mode,
+            &frame->fix_type,
+            &frame->sats[0],
+            &frame->sats[1],
+            &frame->sats[2],
+            &frame->sats[3],
+            &frame->sats[4],
+            &frame->sats[5],
+            &frame->sats[6],
+            &frame->sats[7],
+            &frame->sats[8],
+            &frame->sats[9],
+            &frame->sats[10],
+            &frame->sats[11],
+            &frame->pdop,
+            &frame->hdop,
+            &frame->vdop))
+        return false;
+    if (strcmp(type+2, "GSA"))
+        return false;
+
+    return true;
+}
+
+bool minmea_parse_gll(struct minmea_sentence_gll *frame, const char *sentence)
+{
+    // $GPGLL,3723.2475,N,12158.3416,W,161229.487,A,A*41$;
+    char type[6];
+    int latitude_direction;
+    int longitude_direction;
+
+    if (!minmea_scan(sentence, "tfdfdTc;c",
+            type,
+            &frame->latitude, &latitude_direction,
+            &frame->longitude, &longitude_direction,
+            &frame->time,
+            &frame->status,
+            &frame->mode))
+        return false;
+    if (strcmp(type+2, "GLL"))
+        return false;
+
+    frame->latitude.value *= latitude_direction;
+    frame->longitude.value *= longitude_direction;
+
+    return true;
+}
+
+bool minmea_parse_gst(struct minmea_sentence_gst *frame, const char *sentence)
+{
+    // $GPGST,024603.00,3.2,6.6,4.7,47.3,5.8,5.6,22.0*58
+    char type[6];
+
+    if (!minmea_scan(sentence, "tTfffffff",
+            type,
+            &frame->time,
+            &frame->rms_deviation,
+            &frame->semi_major_deviation,
+            &frame->semi_minor_deviation,
+            &frame->semi_major_orientation,
+            &frame->latitude_error_deviation,
+            &frame->longitude_error_deviation,
+            &frame->altitude_error_deviation))
+        return false;
+    if (strcmp(type+2, "GST"))
+        return false;
+
+    return true;
+}
+
+bool minmea_parse_gsv(struct minmea_sentence_gsv *frame, const char *sentence)
+{
+    // $GPGSV,3,1,11,03,03,111,00,04,15,270,00,06,01,010,00,13,06,292,00*74
+    // $GPGSV,3,3,11,22,42,067,42,24,14,311,43,27,05,244,00,,,,*4D
+    // $GPGSV,4,2,11,08,51,203,30,09,45,215,28*75
+    // $GPGSV,4,4,13,39,31,170,27*40
+    // $GPGSV,4,4,13*7B
+    char type[6];
+
+    if (!minmea_scan(sentence, "tiii;iiiiiiiiiiiiiiii",
+            type,
+            &frame->total_msgs,
+            &frame->msg_nr,
+            &frame->total_sats,
+            &frame->sats[0].nr,
+            &frame->sats[0].elevation,
+            &frame->sats[0].azimuth,
+            &frame->sats[0].snr,
+            &frame->sats[1].nr,
+            &frame->sats[1].elevation,
+            &frame->sats[1].azimuth,
+            &frame->sats[1].snr,
+            &frame->sats[2].nr,
+            &frame->sats[2].elevation,
+            &frame->sats[2].azimuth,
+            &frame->sats[2].snr,
+            &frame->sats[3].nr,
+            &frame->sats[3].elevation,
+            &frame->sats[3].azimuth,
+            &frame->sats[3].snr
+            )) {
+        return false;
+    }
+    if (strcmp(type+2, "GSV"))
+        return false;
+
+    return true;
+}
+
+bool minmea_parse_txt(struct minmea_sentence_txt *frame, const char *sentence)
+{
+    // Example
+    // $GPTXT,01,01,02,u-blox  ag - www.u-blox.com*50
+    char type[6];
+
+    if (!minmea_scan(sentence, "tiii",
+            type,
+            &frame->num_msg,
+            &frame->msg_num,
+            &frame->msgtype)) {
+        return false;
+    }
+    if (strcmp(type+2, "TXT")) {
+        return false;
+    }
+
+    frame->text = sentence + MINMEA_TXT_START_IX;
+    frame->text_len = strlen(sentence) - MINMEA_TXT_START_IX - 5;
+
+    return true;
+}
+
+int minmea_gettime(struct timespec *ts, const struct minmea_date *date, const struct minmea_time *time_)
+{
+    if (date->year == -1 || time_->hours == -1)
+        return -1;
+
+    struct tm tm;
+    memset(&tm, 0, sizeof(tm));
+    tm.tm_year = 2000 + date->year - 1900;
+    tm.tm_mon = date->month - 1;
+    tm.tm_mday = date->day;
+    tm.tm_hour = time_->hours;
+    tm.tm_min = time_->minutes;
+    tm.tm_sec = time_->seconds;
+
+    time_t timestamp = timegm(&tm); /* See README.md if your system lacks timegm(). */
+    if (timestamp != -1) {
+        ts->tv_sec = timestamp;
+        ts->tv_nsec = time_->microseconds * 1000;
+        return 0;
+    } else {
+        return -1;
+    }
+}
+
+/* vim: set ts=4 sw=4 et: */