diff --git a/configure.ac b/configure.ac
index 34cba11..a9c4005 100644
--- a/configure.ac
+++ b/configure.ac
@@ -38,6 +38,9 @@ AM_CONDITIONAL([IRDA], [test "$irda_win32" = "yes" || test "$irda_linux" = "yes"
 AM_CONDITIONAL([IRDA_WIN32], [test "$irda_win32" = "yes"])
 AM_CONDITIONAL([IRDA_LINUX], [test "$irda_linux" = "yes"])
 
+# Checks for library functions.
+AC_CHECK_FUNCS([localtime_r gmtime_r])
+
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_FILES([
    libdivecomputer.pc
diff --git a/msvc/libdivecomputer.vcproj b/msvc/libdivecomputer.vcproj
index 1d62dae..3c46f11 100644
--- a/msvc/libdivecomputer.vcproj
+++ b/msvc/libdivecomputer.vcproj
@@ -192,6 +192,10 @@
 				RelativePath="..\src\cressi_edy.c"
 				>
 			</File>
+			<File
+				RelativePath="..\src\datetime.c"
+				>
+			</File>
 			<File
 				RelativePath="..\src\device.c"
 				>
@@ -378,6 +382,10 @@
 				RelativePath="..\src\cressi_edy.h"
 				>
 			</File>
+			<File
+				RelativePath="..\src\datetime.h"
+				>
+			</File>
 			<File
 				RelativePath="..\src\device-private.h"
 				>
diff --git a/src/Makefile.am b/src/Makefile.am
index b8d6720..ae847b1 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -8,6 +8,7 @@ libdivecomputer_HEADERS = 	\
 	buffer.h \
 	device.h \
 	parser.h \
+	datetime.h \
 	units.h \
 	suunto.h \
 	suunto_solution.h \
@@ -48,6 +49,7 @@ libdivecomputer_la_LDFLAGS = \
 libdivecomputer_la_SOURCES = \
 	device.h device-private.h device.c \
 	parser.h parser-private.h parser.c \
+	datetime.h datetime.c \
 	suunto.h \
 	suunto_common.h suunto_common.c \
 	suunto_common2.h suunto_common2.c \
diff --git a/src/datetime.c b/src/datetime.c
new file mode 100644
index 0000000..619051c
--- /dev/null
+++ b/src/datetime.c
@@ -0,0 +1,112 @@
+/*
+ * libdivecomputer
+ *
+ * Copyright (C) 2010 Jef Driesen
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <time.h>
+
+#include "datetime.h"
+
+static struct tm *
+dc_localtime_r (const time_t *t, struct tm *tm)
+{
+#ifdef HAVE_LOCALTIME_R
+	return localtime_r (t, tm);
+#else
+	struct tm *p = localtime (t);
+	if (p == NULL)
+		return NULL;
+
+	if (tm)
+		*tm = *p;
+
+	return tm;
+#endif
+}
+
+static struct tm *
+dc_gmtime_r (const time_t *t, struct tm *tm)
+{
+#ifdef HAVE_GMTIME_R
+	return gmtime_r (t, tm);
+#else
+	struct tm *p = gmtime (t);
+	if (p == NULL)
+		return NULL;
+
+	if (tm)
+		*tm = *p;
+
+	return tm;
+#endif
+}
+
+dc_ticks_t
+dc_datetime_now (void)
+{
+	return time (NULL);
+}
+
+dc_datetime_t *
+dc_datetime_localtime (dc_datetime_t *result,
+                       dc_ticks_t ticks)
+{
+	time_t t = ticks;
+
+	struct tm tm;
+	if (dc_localtime_r (&t, &tm) == NULL)
+		return NULL;
+
+	if (result) {
+		result->year = tm.tm_year + 1900;
+		result->month = tm.tm_mon + 1;
+		result->day = tm.tm_mday;
+		result->hour = tm.tm_hour;
+		result->minute = tm.tm_min;
+		result->second = tm.tm_sec;
+	}
+
+	return result;
+}
+
+dc_datetime_t *
+dc_datetime_gmtime (dc_datetime_t *result,
+                    dc_ticks_t ticks)
+{
+	time_t t = ticks;
+
+	struct tm tm;
+	if (dc_gmtime_r (&t, &tm) == NULL)
+		return NULL;
+
+	if (result) {
+		result->year = tm.tm_year + 1900;
+		result->month = tm.tm_mon + 1;
+		result->day = tm.tm_mday;
+		result->hour = tm.tm_hour;
+		result->minute = tm.tm_min;
+		result->second = tm.tm_sec;
+	}
+
+	return result;
+}
diff --git a/src/datetime.h b/src/datetime.h
new file mode 100644
index 0000000..ba4dcfd
--- /dev/null
+++ b/src/datetime.h
@@ -0,0 +1,58 @@
+/*
+ * libdivecomputer
+ *
+ * Copyright (C) 2010 Jef Driesen
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#ifndef DC_DATETIME_H
+#define DC_DATETIME_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#ifdef _WIN32
+typedef __int64 dc_ticks_t;
+#else
+typedef long long int dc_ticks_t;
+#endif
+
+typedef struct dc_datetime_t {
+	int year;
+	int month;
+	int day;
+	int hour;
+	int minute;
+	int second;
+} dc_datetime_t;
+
+dc_ticks_t
+dc_datetime_now (void);
+
+dc_datetime_t *
+dc_datetime_localtime (dc_datetime_t *result,
+                       dc_ticks_t ticks);
+
+dc_datetime_t *
+dc_datetime_gmtime (dc_datetime_t *result,
+                    dc_ticks_t ticks);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+#endif /* DC_DATETIME_H */
diff --git a/src/libdivecomputer.symbols b/src/libdivecomputer.symbols
index 0df2290..450c1b9 100644
--- a/src/libdivecomputer.symbols
+++ b/src/libdivecomputer.symbols
@@ -9,6 +9,10 @@ dc_buffer_slice
 dc_buffer_get_size
 dc_buffer_get_data
 
+dc_datetime_now
+dc_datetime_localtime
+dc_datetime_gmtime
+
 parser_get_type
 parser_set_data
 parser_samples_foreach