Start populating the maintab Dive Info widget

Establish some useful helpers and use them when updating the values.

One of the helpers (from statistics.c) puzzlingly doesn't link - so that's
ifdefed out.

Also had to re-arrange the settings reading code (it came too late) and to
extract the expanding code of the top dive from the settings reading code
(as it had no business being there to begin with).

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/statistics.c b/statistics.c
index 7532e346e..bee5837d6 100644
--- a/statistics.c
+++ b/statistics.c
@@ -267,3 +267,18 @@ void get_selected_dives_text(char *buffer, int size)
 	}
 }
 
+volume_t get_gas_used(struct dive *dive)
+{
+	int idx;
+	volume_t gas_used = { 0 };
+	for (idx = 0; idx < MAX_CYLINDERS; idx++) {
+		cylinder_t *cyl = &dive->cylinder[idx];
+		pressure_t start, end;
+
+		start = cyl->start.mbar ? cyl->start : cyl->sample_start;
+		end = cyl->end.mbar ?cyl->sample_end : cyl->sample_end;
+		if (start.mbar && end.mbar)
+			gas_used.mliter += gas_volume(cyl, start) - gas_volume(cyl, end);
+	}
+	return gas_used;
+}