First commit

Signed-off-by: Mattias Andrée <m@maandree.se>

1 files changed, 38 insertions, 0 deletions

diff --git a/libgeome_get_from_time.c b/libgeome_get_from_time.c
new file mode 100644
index 0000000..b512a34
--- /dev/null
+++ b/libgeome_get_from_time.c
@@ -0,0 +1,38 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+int
+libgeome_get_from_time(struct libgeome_context *ctx, struct libgeome_data *out)
+{
+	time_t utc, local, uoff;
+	struct tm tm;
+
+	utc = time(NULL);
+	if (utc < 0) {
+		ctx->print_error(ctx, "time: %s\n", strerror(errno));
+		return -1;
+        }
+        if (!localtime_r(&utc, &tm)) {
+		ctx->print_error(ctx, "localtime_r: %s\n", strerror(errno));
+                return -1;
+        }
+
+	local = (time_t)(tm.tm_hour * 60 * 60);
+	local += (time_t)(tm.tm_min * 60);
+	local += (time_t)tm.tm_sec;
+	utc %= (time_t)(24 * 60 * 60);
+	uoff = local - utc;
+
+	out->requested_data &= LIBGEOME_DATUM_LONGITUDE;
+	if (out->requested_data) {
+		out->longitude = (double)uoff / (24 * 60 * 60 / 360);
+		out->longitude = fmod(out->longitude, 360);
+		if (out->longitude < -180)
+			out->longitude += 360;
+		else if (out->longitude > 180)
+			out->longitude -= 360;
+	}
+
+	return 0;
+}