Fix time zone issues in 32bit builds

The bug is obvious, tracking it down wasn't.
A simple thinko brought us time_t instead of timestamp_t - which doesn't
matter on 64bit builds, but makes things fail in weird ways on 32bit
builds - like our Windows binaries.
In this case instead of checking today's date to detect the timezone
offset we happened to be using a date in December 1969, so no dailight
savings, so the times were off.

Fixes #655
Fixes #667
See #670

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

1 files changed, 1 insertions, 1 deletions

diff --git a/helpers.h b/helpers.h
index 06a431779..56532d5c4 100644
--- a/helpers.h
+++ b/helpers.h
@@ -27,7 +27,7 @@ void set_default_dive_computer(const char *vendor, const char *product);
 void set_default_dive_computer_device(const char *name);
 QString getSubsurfaceDataPath(QString folderToFind);
 extern const QString get_dc_nickname(const char *model, uint32_t deviceid);
-int gettimezoneoffset(time_t when = 0);
+int gettimezoneoffset(timestamp_t when = 0);
 int parseTemperatureToMkelvin(const QString &text);
 QString get_dive_date_string(timestamp_t when);
 QString get_short_dive_date_string(timestamp_t when);