Refactor time_* into nstime_*.

Use a single uint64_t in nstime_t to store nanoseconds rather than using
struct timespec.  This reduces fragility around conversions between long
and uint64_t, especially missing casts that only cause problems on
32-bit platforms.

src/nstime.c

@@ -0,0 +1,148 @@
+#include "jemalloc/internal/jemalloc_internal.h"
+
+#define	BILLION	UINT64_C(1000000000)
+
+void
+nstime_init(nstime_t *time, uint64_t ns)
+{
+
+	time->ns = ns;
+}
+
+void
+nstime_init2(nstime_t *time, uint64_t sec, uint64_t nsec)
+{
+
+	time->ns = sec * BILLION + nsec;
+}
+
+uint64_t
+nstime_ns(const nstime_t *time)
+{
+
+	return (time->ns);
+}
+
+uint64_t
+nstime_sec(const nstime_t *time)
+{
+
+	return (time->ns / BILLION);
+}
+
+uint64_t
+nstime_nsec(const nstime_t *time)
+{
+
+	return (time->ns % BILLION);
+}
+
+void
+nstime_copy(nstime_t *time, const nstime_t *source)
+{
+
+	*time = *source;
+}
+
+int
+nstime_compare(const nstime_t *a, const nstime_t *b)
+{
+
+	return ((a->ns > b->ns) - (a->ns < b->ns));
+}
+
+void
+nstime_add(nstime_t *time, const nstime_t *addend)
+{
+
+	assert(UINT64_MAX - time->ns >= addend->ns);
+
+	time->ns += addend->ns;
+}
+
+void
+nstime_subtract(nstime_t *time, const nstime_t *subtrahend)
+{
+
+	assert(nstime_compare(time, subtrahend) >= 0);
+
+	time->ns -= subtrahend->ns;
+}
+
+void
+nstime_imultiply(nstime_t *time, uint64_t multiplier)
+{
+
+	assert((((time->ns | multiplier) & (UINT64_MAX << (sizeof(uint64_t) <<
+	    2))) == 0) || ((time->ns * multiplier) / multiplier == time->ns));
+
+	time->ns *= multiplier;
+}
+
+void
+nstime_idivide(nstime_t *time, uint64_t divisor)
+{
+
+	assert(divisor != 0);
+
+	time->ns /= divisor;
+}
+
+uint64_t
+nstime_divide(const nstime_t *time, const nstime_t *divisor)
+{
+
+	assert(divisor->ns != 0);
+
+	return (time->ns / divisor->ns);
+}
+
+#ifdef JEMALLOC_JET
+#undef nstime_update
+#define	nstime_update JEMALLOC_N(nstime_update_impl)
+#endif
+bool
+nstime_update(nstime_t *time)
+{
+	nstime_t old_time;
+
+	nstime_copy(&old_time, time);
+
+#ifdef _WIN32
+	{
+		FILETIME ft;
+		uint64_t ticks;
+		GetSystemTimeAsFileTime(&ft);
+		ticks = (((uint64_t)ft.dwHighDateTime) << 32) |
+		    ft.dwLowDateTime;
+		time->ns = ticks * 100;
+	}
+#elif JEMALLOC_CLOCK_GETTIME
+	{
+		struct timespec ts;
+
+		if (sysconf(_SC_MONOTONIC_CLOCK) > 0)
+			clock_gettime(CLOCK_MONOTONIC, &ts);
+		else
+			clock_gettime(CLOCK_REALTIME, &ts);
+		time->ns = ts.tv_sec * BILLION + ts.tv_nsec;
+	}
+#else
+	struct timeval tv;
+	gettimeofday(&tv, NULL);
+	time->ns = tv.tv_sec * BILLION + tv.tv_usec * 1000;
+#endif
+
+	/* Handle non-monotonic clocks. */
+	if (unlikely(nstime_compare(&old_time, time) > 0)) {
+		nstime_copy(time, &old_time);
+		return (true);
+	}
+
+	return (false);
+}
+#ifdef JEMALLOC_JET
+#undef nstime_update
+#define	nstime_update JEMALLOC_N(nstime_update)
+nstime_update_t *nstime_update = JEMALLOC_N(nstime_update_impl);
+#endif