LiXiaoqi/minmea
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minmea: don't include talker id in sentence type.

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This is a backwards-incompatible change that I knew I'd have to
introduce sooner or later. Which means now.

Long story short: when I first started writing this library, I wanted to
make things simpler by treating the entire talker+sentence as one big
ID. Of course, this is an oversimplification, as there are different
talkers out there.

Turns out they're more common than I initially thought. I just came
across a module (read: I had one soldered to my board by our crazy
hardware guy) that spits out GPRMC, GLRMC or GNRMC depending on where it
got the data. I could have kludged around this, but here's this change,
for the purity of code.

Fortunately, we're the only users of this codebase as far as I know, so
no real harm is done - but it's a lesson to design my interfaces right
from the very start so I don't have to break compatibility and write
apologetic messages later on.
This commit is contained in:
Kosma Moczek 2014-03-24 22:40:25 +01:00
parent 3b3179a000
commit d973b98d66
5 changed files with 74 additions and 77 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
README.md
View File

@ -53,10 +53,10 @@ The library doesn't perform this conversion automatically for the following reas
char line[MINMEA_MAX_LENGTH]; char line[MINMEA_MAX_LENGTH];
while (fgets(line, sizeof(line), stdin) != NULL) { while (fgets(line, sizeof(line), stdin) != NULL) {
printf("%s", line); printf("%s", line);
switch (minmea_type(line)) { switch (minmea_sentence_id(line)) {
case MINMEA_GPRMC: { case MINMEA_SENTENCE_RMC: {
struct minmea_gprmc frame; struct minmea_sentence_rmc frame;
if (minmea_parse_gprmc(&frame, line)) { if (minmea_parse_rmc(&frame, line)) {
printf("+++ raw coordinates and speed: (%d/%d,%d/%d) %d/%d\n", printf("+++ raw coordinates and speed: (%d/%d,%d/%d) %d/%d\n",
frame.latitude, frame.latitude_scale, frame.latitude, frame.latitude_scale,
frame.longitude, frame.longitude_scale, frame.longitude, frame.longitude_scale,
@ -72,15 +72,12 @@ The library doesn't perform this conversion automatically for the following reas
} }
} break; } break;
case MINMEA_GPGGA: { case MINMEA_SENTENCE_GGA: {
struct minmea_gpgga frame; struct minmea_sentence_gga frame;
if (minmea_parse_gpgga(&frame, line)) { if (minmea_parse_gga(&frame, line)) {
printf("$GPGGA: fix quality: %d\n", frame.fix_quality); printf("$GPGGA: fix quality: %d\n", frame.fix_quality);
} }
} break; } break;
default: {
} break;
} }
} }
``` ```

14
example.c
View File

@ -17,10 +17,10 @@ int main()
char line[MINMEA_MAX_LENGTH]; char line[MINMEA_MAX_LENGTH];
while (fgets(line, sizeof(line), stdin) != NULL) { while (fgets(line, sizeof(line), stdin) != NULL) {
printf("%s", line); printf("%s", line);
switch (minmea_type(line)) { switch (minmea_sentence_id(line)) {
case MINMEA_GPRMC: { case MINMEA_SENTENCE_RMC: {
struct minmea_gprmc frame; struct minmea_sentence_rmc frame;
if (minmea_parse_gprmc(&frame, line)) { if (minmea_parse_rmc(&frame, line)) {
printf("+++ raw coordinates and speed: (%d/%d,%d/%d) %d/%d\n", printf("+++ raw coordinates and speed: (%d/%d,%d/%d) %d/%d\n",
frame.latitude, frame.latitude_scale, frame.latitude, frame.latitude_scale,
frame.longitude, frame.longitude_scale, frame.longitude, frame.longitude_scale,
@ -36,9 +36,9 @@ int main()
} }
} break; } break;
case MINMEA_GPGGA: { case MINMEA_SENTENCE_GGA: {
struct minmea_gpgga frame; struct minmea_sentence_gga frame;
if (minmea_parse_gpgga(&frame, line)) { if (minmea_parse_gga(&frame, line)) {
printf("$GPGGA: fix quality: %d\n", frame.fix_quality); printf("$GPGGA: fix quality: %d\n", frame.fix_quality);
} }
} break; } break;

28
minmea.c
View File

@ -175,7 +175,7 @@ bool minmea_scan(const char *sentence, const char *format, ...)
*buf = '\0'; *buf = '\0';
} break; } break;
case 't': { // NMEA talker+sequence identifier (char *). case 't': { // NMEA talker+sentence identifier (char *).
if (field[0] != '$') if (field[0] != '$')
goto end; goto end;
for (int i=0; i<5; i++) for (int i=0; i<5; i++)
@ -259,7 +259,7 @@ end:
return result; return result;
} }
enum minmea_type minmea_type(const char *sentence) enum minmea_sentence_id minmea_sentence_id(const char *sentence)
{ {
if (!minmea_check(sentence)) if (!minmea_check(sentence))
return MINMEA_INVALID; return MINMEA_INVALID;
@ -268,17 +268,17 @@ enum minmea_type minmea_type(const char *sentence)
if (!minmea_scan(sentence, "t", type)) if (!minmea_scan(sentence, "t", type))
return MINMEA_INVALID; return MINMEA_INVALID;
if (!strcmp(type, "GPRMC")) if (!strcmp(type+2, "RMC"))
return MINMEA_GPRMC; return MINMEA_SENTENCE_RMC;
if (!strcmp(type, "GPGGA")) if (!strcmp(type+2, "GGA"))
return MINMEA_GPGGA; return MINMEA_SENTENCE_GGA;
if (!strcmp(type, "GPGSA")) if (!strcmp(type+2, "GSA"))
return MINMEA_GPGSA; return MINMEA_SENTENCE_GSA;
return MINMEA_UNKNOWN; return MINMEA_UNKNOWN;
} }
bool minmea_parse_gprmc(struct minmea_gprmc *frame, const char *sentence) 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 // $GPRMC,081836,A,3751.65,S,14507.36,E,000.0,360.0,130998,011.3,E*62
char type[6]; char type[6];
@ -297,7 +297,7 @@ bool minmea_parse_gprmc(struct minmea_gprmc *frame, const char *sentence)
&frame->date, &frame->date,
&frame->variation, &frame->variation_scale, &variation_direction)) &frame->variation, &frame->variation_scale, &variation_direction))
return false; return false;
if (strcmp(type, "GPRMC")) if (strcmp(type+2, "RMC"))
return false; return false;
frame->valid = (validity == 'A'); frame->valid = (validity == 'A');
@ -308,7 +308,7 @@ bool minmea_parse_gprmc(struct minmea_gprmc *frame, const char *sentence)
return true; return true;
} }
bool minmea_parse_gpgga(struct minmea_gpgga *frame, const char *sentence) 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 // $GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47
char type[6]; char type[6];
@ -327,7 +327,7 @@ bool minmea_parse_gpgga(struct minmea_gpgga *frame, const char *sentence)
&frame->height, &frame->height_scale, &frame->height_units, &frame->height, &frame->height_scale, &frame->height_units,
&frame->dgps_age)) &frame->dgps_age))
return false; return false;
if (strcmp(type, "GPGGA")) if (strcmp(type+2, "GGA"))
return false; return false;
frame->latitude *= latitude_direction; frame->latitude *= latitude_direction;
@ -336,7 +336,7 @@ bool minmea_parse_gpgga(struct minmea_gpgga *frame, const char *sentence)
return true; return true;
} }
bool minmea_parse_gpgsa(struct minmea_gpgsa *frame, const char *sentence) 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 // $GPGSA,A,3,04,05,,09,12,,,24,,,,,2.5,1.3,2.1*39
char type[6]; char type[6];
@ -366,7 +366,7 @@ bool minmea_parse_gpgsa(struct minmea_gpgsa *frame, const char *sentence)
)){ )){
return false; return false;
} }
if (strcmp(type, "GPGSA")) if (strcmp(type+2, "GSA"))
return false; return false;
return true; return true;

32
minmea.h
View File

@ -23,12 +23,12 @@ extern "C" {
#define MINMEA_MAX_LENGTH 80 #define MINMEA_MAX_LENGTH 80
enum minmea_type { enum minmea_sentence_id {
MINMEA_INVALID = -1, MINMEA_INVALID = -1,
MINMEA_UNKNOWN = 0, MINMEA_UNKNOWN = 0,
MINMEA_GPRMC, MINMEA_SENTENCE_RMC,
MINMEA_GPGGA, MINMEA_SENTENCE_GGA,
MINMEA_GPGSA, MINMEA_SENTENCE_GSA,
}; };
struct minmea_date { struct minmea_date {
@ -44,7 +44,7 @@ struct minmea_time {
int microseconds; int microseconds;
}; };
struct minmea_gprmc { struct minmea_sentence_rmc {
struct minmea_time time; struct minmea_time time;
bool valid; bool valid;
int latitude, latitude_scale; int latitude, latitude_scale;
@ -55,7 +55,7 @@ struct minmea_gprmc {
int variation, variation_scale; int variation, variation_scale;
}; };
struct minmea_gpgga { struct minmea_sentence_gga {
struct minmea_time time; struct minmea_time time;
int latitude, latitude_scale; int latitude, latitude_scale;
int longitude, longitude_scale; int longitude, longitude_scale;
@ -67,18 +67,18 @@ struct minmea_gpgga {
int dgps_age; int dgps_age;
}; };
enum minmea_gpgsa_mode { enum minmea_gsa_mode {
MINMEA_GPGSA_MODE_AUTO = 'A', MINMEA_GPGSA_MODE_AUTO = 'A',
MINMEA_GPGSA_MODE_FORCED = 'M', MINMEA_GPGSA_MODE_FORCED = 'M',
}; };
enum minmea_gpgsa_fix_type { enum minmea_gsa_fix_type {
MINMEA_GPGSA_FIX_NONE = 1, MINMEA_GPGSA_FIX_NONE = 1,
MINMEA_GPGSA_FIX_2D = 2, MINMEA_GPGSA_FIX_2D = 2,
MINMEA_GPGSA_FIX_3D = 3, MINMEA_GPGSA_FIX_3D = 3,
}; };
struct minmea_gpgsa { struct minmea_sentence_gsa {
char mode; char mode;
int fix_type; int fix_type;
int sats[12]; int sats[12];
@ -88,14 +88,14 @@ struct minmea_gpgsa {
}; };
/** /**
* Check sequence validity and checksum. Returns true for valid sequences. * Check sentence validity and checksum. Returns true for valid sentences.
*/ */
bool minmea_check(const char *sentence); bool minmea_check(const char *sentence);
/** /**
* Determine sequence type. * Determine sentence identifier.
*/ */
enum minmea_type minmea_type(const char *sequence); enum minmea_sentence_id minmea_sentence_id(const char *sentence);
/** /**
* Scanf-like processor for NMEA sentences. Supports the following formats: * Scanf-like processor for NMEA sentences. Supports the following formats:
@ -111,11 +111,11 @@ enum minmea_type minmea_type(const char *sequence);
bool minmea_scan(const char *sentence, const char *format, ...); bool minmea_scan(const char *sentence, const char *format, ...);
/* /*
* Parse a specific type of frame. Return true on success. * Parse a specific type of sentence. Return true on success.
*/ */
bool minmea_parse_gprmc(struct minmea_gprmc *frame, const char *sentence); bool minmea_parse_rmc(struct minmea_sentence_rmc *frame, const char *sentence);
bool minmea_parse_gpgga(struct minmea_gpgga *frame, const char *sentence); bool minmea_parse_gga(struct minmea_sentence_gga *frame, const char *sentence);
bool minmea_parse_gpgsa(struct minmea_gpgsa *frame, const char *sentence); bool minmea_parse_gsa(struct minmea_sentence_gsa *frame, const char *sentence);
/** /**
* Convert GPS UTC date/time representation to a UNIX timestamp. * Convert GPS UTC date/time representation to a UNIX timestamp.

60
tests.c
View File

@ -284,11 +284,11 @@ START_TEST(test_minmea_scan_complex2)
} }
END_TEST END_TEST
START_TEST(test_minmea_parse_gprmc1) START_TEST(test_minmea_parse_rmc1)
{ {
const char *sentence = "$GPRMC,081836.75,A,3751.65,S,14507.36,E,000.0,360.0,130998,011.3,E"; const char *sentence = "$GPRMC,081836.75,A,3751.65,S,14507.36,E,000.0,360.0,130998,011.3,E";
struct minmea_gprmc frame = {}; struct minmea_sentence_rmc frame = {};
struct minmea_gprmc expected = { struct minmea_sentence_rmc expected = {
.time = { 8, 18, 36, 750000 }, .time = { 8, 18, 36, 750000 },
.valid = true, .valid = true,
.latitude = -375165, .latitude = -375165,
@ -304,16 +304,16 @@ START_TEST(test_minmea_parse_gprmc1)
.variation_scale = 10, .variation_scale = 10,
}; };
ck_assert(minmea_check(sentence) == true); ck_assert(minmea_check(sentence) == true);
ck_assert(minmea_parse_gprmc(&frame, sentence) == true); ck_assert(minmea_parse_rmc(&frame, sentence) == true);
ck_assert(!memcmp(&frame, &expected, sizeof(frame))); ck_assert(!memcmp(&frame, &expected, sizeof(frame)));
} }
END_TEST END_TEST
START_TEST(test_minmea_parse_gprmc2) START_TEST(test_minmea_parse_rmc2)
{ {
const char *sentence = "$GPRMC,,A,3751.65,N,14507.36,W,,,,,"; const char *sentence = "$GPRMC,,A,3751.65,N,14507.36,W,,,,,";
struct minmea_gprmc frame = {}; struct minmea_sentence_rmc frame = {};
struct minmea_gprmc expected = { struct minmea_sentence_rmc expected = {
.time = { -1, -1, -1, -1 }, .time = { -1, -1, -1, -1 },
.valid = true, .valid = true,
.latitude = 375165, .latitude = 375165,
@ -323,16 +323,16 @@ START_TEST(test_minmea_parse_gprmc2)
.date = { -1, -1, -1 }, .date = { -1, -1, -1 },
}; };
ck_assert(minmea_check(sentence) == true); ck_assert(minmea_check(sentence) == true);
ck_assert(minmea_parse_gprmc(&frame, sentence) == true); ck_assert(minmea_parse_rmc(&frame, sentence) == true);
ck_assert(!memcmp(&frame, &expected, sizeof(frame))); ck_assert(!memcmp(&frame, &expected, sizeof(frame)));
} }
END_TEST END_TEST
START_TEST(test_minmea_parse_gpgga1) START_TEST(test_minmea_parse_gga1)
{ {
const char *sentence = "$GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47"; const char *sentence = "$GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47";
struct minmea_gpgga frame = {}; struct minmea_sentence_gga frame = {};
struct minmea_gpgga expected = { struct minmea_sentence_gga expected = {
.time = { 12, 35, 19, 0 }, .time = { 12, 35, 19, 0 },
.latitude = 4807038, .latitude = 4807038,
.latitude_scale = 1000, .latitude_scale = 1000,
@ -351,16 +351,16 @@ START_TEST(test_minmea_parse_gpgga1)
.dgps_age = 0, .dgps_age = 0,
}; };
ck_assert(minmea_check(sentence) == true); ck_assert(minmea_check(sentence) == true);
ck_assert(minmea_parse_gpgga(&frame, sentence) == true); ck_assert(minmea_parse_gga(&frame, sentence) == true);
ck_assert(!memcmp(&frame, &expected, sizeof(frame))); ck_assert(!memcmp(&frame, &expected, sizeof(frame)));
} }
END_TEST END_TEST
START_TEST(test_minmea_parse_gpgsa1) START_TEST(test_minmea_parse_gsa1)
{ {
const char *sentence = "$GPGSA,A,3,04,05,,09,12,,,24,,,,,2.5,1.3,2.1*39"; const char *sentence = "$GPGSA,A,3,04,05,,09,12,,,24,,,,,2.5,1.3,2.1*39";
struct minmea_gpgsa frame = {}; struct minmea_sentence_gsa frame = {};
struct minmea_gpgsa expected = { struct minmea_sentence_gsa expected = {
.mode = MINMEA_GPGSA_MODE_AUTO, .mode = MINMEA_GPGSA_MODE_AUTO,
.fix_type = MINMEA_GPGSA_FIX_3D, .fix_type = MINMEA_GPGSA_FIX_3D,
.sats = { 4, 5, 0, 9, 12, 0, 0, 24, 0, 0, 0, 0 }, .sats = { 4, 5, 0, 9, 12, 0, 0, 24, 0, 0, 0, 0 },
@ -372,7 +372,7 @@ START_TEST(test_minmea_parse_gpgsa1)
.vdop_scale = 10 .vdop_scale = 10
}; };
ck_assert(minmea_check(sentence) == true); ck_assert(minmea_check(sentence) == true);
ck_assert(minmea_parse_gpgsa(&frame, sentence) == true); ck_assert(minmea_parse_gsa(&frame, sentence) == true);
ck_assert(!memcmp(&frame, &expected, sizeof(frame))); ck_assert(!memcmp(&frame, &expected, sizeof(frame)));
} }
END_TEST END_TEST
@ -387,20 +387,20 @@ START_TEST(test_minmea_usage1)
}; };
for (const char **sentence=sentences; *sentence; sentence++) { for (const char **sentence=sentences; *sentence; sentence++) {
switch (minmea_type(*sentence)) { switch (minmea_sentence_id(*sentence)) {
case MINMEA_GPRMC: { case MINMEA_SENTENCE_RMC: {
struct minmea_gprmc frame; struct minmea_sentence_rmc frame;
ck_assert(minmea_parse_gprmc(&frame, *sentence) == true); ck_assert(minmea_parse_rmc(&frame, *sentence) == true);
} break; } break;
case MINMEA_GPGGA: { case MINMEA_SENTENCE_GGA: {
struct minmea_gpgga frame; struct minmea_sentence_gga frame;
ck_assert(minmea_parse_gpgga(&frame, *sentence) == true); ck_assert(minmea_parse_gga(&frame, *sentence) == true);
} break; } break;
case MINMEA_GPGSA: { case MINMEA_SENTENCE_GSA: {
struct minmea_gpgsa frame; struct minmea_sentence_gsa frame;
ck_assert(minmea_parse_gpgsa(&frame, *sentence) == true); ck_assert(minmea_parse_gsa(&frame, *sentence) == true);
} break; } break;
@ -486,10 +486,10 @@ Suite *minmea_suite(void)
suite_add_tcase(s, tc_scan); suite_add_tcase(s, tc_scan);
TCase *tc_parse = tcase_create("minmea_parse"); TCase *tc_parse = tcase_create("minmea_parse");
tcase_add_test(tc_parse, test_minmea_parse_gprmc1); tcase_add_test(tc_parse, test_minmea_parse_rmc1);
tcase_add_test(tc_parse, test_minmea_parse_gprmc2); tcase_add_test(tc_parse, test_minmea_parse_rmc2);
tcase_add_test(tc_parse, test_minmea_parse_gpgga1); tcase_add_test(tc_parse, test_minmea_parse_gga1);
tcase_add_test(tc_parse, test_minmea_parse_gpgsa1); tcase_add_test(tc_parse, test_minmea_parse_gsa1);
suite_add_tcase(s, tc_parse); suite_add_tcase(s, tc_parse);
TCase *tc_usage = tcase_create("minmea_usage"); TCase *tc_usage = tcase_create("minmea_usage");