X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=dive.c;h=54784cdbabfb01fbb5c5a8db539cdc481f20c613;hb=refs%2Fheads%2Fmaster;hp=f4bf497a7da0edeafb91b5a26b1de067f87d64b7;hpb=d2d4364afcc3fb310ea43573f0d455f90c9212ce;p=ext%2Fsubsurface.git

diff --git a/dive.c b/dive.c
index f4bf497..54784cd 100644
--- a/dive.c
+++ b/dive.c
@@ -472,11 +472,19 @@ struct dive *fixup_dive(struct dive *dive)
 			cyl->sample_end.mbar = 0;
 		}
 	}
-	if (end < 0)
-	{
+	if (end < 0) {
 		/* Assume an ascent/descent rate of 9 m/min */
-		int asc_desc_time = dive->maxdepth.mm*60/9000;
-		dive->meandepth.mm = dive->maxdepth.mm*(dive->duration.seconds-asc_desc_time)/dive->duration.seconds;
+		int depth = dive->maxdepth.mm;
+		int asc_desc_time = depth*60/9000;
+		int duration = dive->duration.seconds;
+
+		/* Some sanity checks against insane dives */
+		if (duration < 2)
+			duration = 2;
+		if (asc_desc_time * 2 >= duration)
+			asc_desc_time = duration/2;
+
+		dive->meandepth.mm = depth*(duration-asc_desc_time)/duration;
 		return dive;
 	}