Store the user's unit preferences in git storage

Save and load a usually unused copy of the preferences with the units that
were active the last time the dive list was saved to git storage (this
isn't used in XML files); storing the unit preferences in the data file is
usually pointless (that's a setting of the software, not a property of the
data), but it's a great hint of what the user might expect to see when
creating a backend service that visualizes the dive list without
Subsurface running - so this is basically a functionality for the core
library that Subsurface itself doesn't use but that another consumer of
the library (like an HTML exporter) will need.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/dive.h b/dive.h
index 6d142fd3e..36d9a1200 100644
--- a/dive.h
+++ b/dive.h
@@ -858,6 +858,7 @@ extern double strtod_flags(const char *str, const char **ptr, unsigned int flags
 
 extern void set_save_userid_local(short value);
 extern void set_userid(char *user_id);
+extern void set_informational_units(char *units);
 
 extern const char *get_dive_date_c_string(timestamp_t when);
 extern void update_setpoint_events(struct divecomputer *dc);