Fix depth calculations in SDA import

stole and fixed Linus' code in the uemis XML importer

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/uemis.c b/uemis.c
index 7f431cba6b82e2599e5abb21a010a3082ca28237..5cede0facce9b161bde15db1e1ab2b8903cff38e 100644 (file)
--- a/uemis.c
+++ b/uemis.c
@@ -134,6 +134,24 @@ int matchit(FILE *infd, char *regex, char *typeregex, char **found) {
        return 0;
 }
 
+/*
+ * pressure_to_depth: In centibar. And when converting to
+ * depth, I'm just going to always use saltwater, because I
+ * think "true depth" is just stupid. From a diving standpoint,
+ * "true depth" is pretty much completely pointless, unless
+ * you're doing some kind of underwater surveying work.
+ *
+ * So I give water depths in "pressure depth", always assuming
+ * salt water. So one atmosphere per 10m.
+ */
+static int pressure_to_depth(uint16_t value)
+{
+       double atm, cm;
+
+       atm = (value / 100.0) / 1.01325;
+       cm = 100 * atm + 0.5;
+       return( (cm > 0) ? 10 * (long)cm : 0);
+}
 
 /*
  * convert the base64 data blog
@@ -170,6 +188,7 @@ static void parse_divelog_binary(char *base64, struct dive **divep) {
        int i;
        uint8_t *data;
        struct sample *sample;
+       struct dive *dive = *divep;
 
        datalen = uemis_convert_base64(base64, &data);
 
@@ -177,15 +196,21 @@ static void parse_divelog_binary(char *base64, struct dive **divep) {
        i = 0x123;
        while ((i < datalen) && (*(uint16_t *)(data+i))) {
                /* it seems that a dive_time of 0 indicates the end of the valid readings */
+               /* the SDA usually records more samples after the end of the dive --
+                * we want to discard those, but not cut the dive short; sadly the dive
+                * duration in the header is a) in minutes and b) up to 3 minutes short */
+               if (*(uint16_t *)(data+i) > dive->duration.seconds + 180)
+                       break;
                sample = prepare_sample(divep);
                sample->time.seconds = *(uint16_t *)(data+i);
-               sample->depth.mm = (*(uint16_t *)(data+i+2) - 100) / 0.101428571 + 0.5;
+               sample->depth.mm = pressure_to_depth(*(uint16_t *)(data+i+2));
                sample->temperature.mkelvin = (*(uint16_t *)(data+i+4) * 100) + 273150;
                sample->cylinderpressure.mbar= *(uint16_t *)(data+i+23) * 10;
                sample->cylinderindex = *(uint8_t *)(data+i+22);
                finish_sample(*divep, sample);
                i += 0x25;
        }
+       dive->duration.seconds = sample->time.seconds - 1;
        return;
 }
 
@@ -217,7 +242,7 @@ parse_uemis_file(char *divelogfilename,GError **error) {
                /* some error handling */
                goto bail;
        }
-       dive->maxdepth.mm = atof(found) / 0.10143 + 0.5;
+       dive->maxdepth.mm = pressure_to_depth(atoi(found));
 
        if (! matchit(divelogfile,"<val key=\"file_content\">",
                        ">\\([a-zA-Z0-9+/]*\\)<", &found)) {