Refactor headers

[wimlib] / include / wimlib / timestamp.h

diff --git a/include/wimlib/timestamp.h b/include/wimlib/timestamp.h
new file mode 100644 (file)
index 0000000..14a2eb1
--- /dev/null
+++ b/include/wimlib/timestamp.h
@@ -0,0 +1,77 @@
+#ifndef _WIMLIB_TIMESTAMP_H
+#define _WIMLIB_TIMESTAMP_H
+
+#include "wimlib/types.h"
+#include <sys/types.h>
+#include <sys/time.h>
+#include <time.h>
+
+#define intervals_per_second (1000000000ULL / 100ULL)
+#define intervals_per_microsecond (10)
+#define nanoseconds_per_interval (100)
+#define days_per_year (365ULL)
+#define seconds_per_day (3600ULL * 24ULL)
+#define intervals_per_day (seconds_per_day * intervals_per_second)
+#define intervals_per_year (intervals_per_day * days_per_year)
+#define years_1601_to_1970 (1970ULL - 1601ULL)
+#define leap_years_1601_to_1970 (years_1601_to_1970 / 4ULL - 3ULL)
+#define intervals_1601_to_1970 (years_1601_to_1970 * intervals_per_year \
+                               + leap_years_1601_to_1970 * intervals_per_day)
+
+static inline u64
+unix_timestamp_to_wim(time_t t)
+{
+       return (u64)intervals_1601_to_1970 + t * intervals_per_second;
+}
+
+/* Converts a timestamp as used in the WIM file to a UNIX timestamp as used in
+ * the time() function. */
+static inline time_t
+wim_timestamp_to_unix(u64 timestamp)
+{
+       return (timestamp - intervals_1601_to_1970) / intervals_per_second;
+}
+
+static inline u64
+timeval_to_wim_timestamp(const struct timeval tv)
+{
+       return intervals_1601_to_1970
+              + (u64)tv.tv_sec * intervals_per_second
+              + (u64)tv.tv_usec * intervals_per_microsecond;
+}
+
+static inline struct timeval
+wim_timestamp_to_timeval(u64 timestamp)
+{
+       struct timeval tv;
+       tv.tv_sec = (timestamp - intervals_1601_to_1970) / intervals_per_second;
+       tv.tv_usec = ((timestamp - intervals_1601_to_1970) /
+                       intervals_per_microsecond) % 1000000;
+       return tv;
+}
+
+static inline u64
+timespec_to_wim_timestamp(const struct timespec ts)
+{
+       return intervals_1601_to_1970
+              + (u64)ts.tv_sec * intervals_per_second
+              + (u64)ts.tv_nsec / nanoseconds_per_interval;
+}
+
+static inline struct timespec
+wim_timestamp_to_timespec(u64 timestamp)
+{
+       struct timespec ts;
+       ts.tv_sec = (timestamp - intervals_1601_to_1970) / intervals_per_second;
+       ts.tv_nsec = ((timestamp - intervals_1601_to_1970) % intervals_per_second) *
+                       nanoseconds_per_interval;
+       return ts;
+}
+
+extern u64
+get_wim_timestamp(void);
+
+extern void
+wim_timestamp_to_str(u64 timestamp, tchar *buf, size_t len);
+
+#endif