X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=tv.c;fp=tv.c;h=ec2cdc2f470ab02a5416293a790988aa938d4528;hb=6c76799c7334a12926dc1cf0c32670423cbc954f;hp=0000000000000000000000000000000000000000;hpb=66cdd5bc99a53d2b408a6cdc2d501fe27f9db13b;p=dss.git

diff --git a/tv.c b/tv.c
new file mode 100644
index 0000000..ec2cdc2
--- /dev/null
+++ b/tv.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+
+#include <sys/time.h>
+#include <time.h>
+#include <inttypes.h>
+#include <assert.h>
+#include <string.h>
+
+#include "gcc-compat.h"
+#include "err.h"
+#include "str.h"
+#include "log.h"
+#include "time.h"
+
+/**
+ * Convert struct timeval to milliseconds.
+ *
+ * \param tv The time value value to convert.
+ *
+ * \return The number off milliseconds in \a tv.
+ */
+long unsigned tv2ms(const struct timeval *tv)
+{
+	return tv->tv_sec * 1000 + (tv->tv_usec + 500)/ 1000;
+}
+
+/**
+ * Convert milliseconds to a struct timeval.
+ *
+ * \param n The number of milliseconds.
+ * \param tv Result pointer.
+ */
+void ms2tv(long unsigned n, struct timeval *tv)
+{
+	tv->tv_sec = n / 1000;
+	tv->tv_usec = (n % 1000) * 1000;
+}
+
+/**
+ * Convert a double to a struct timeval.
+ *
+ * \param x The value to convert.
+ * \param tv Result pointer.
+ */
+void d2tv(double x, struct timeval *tv)
+{
+	tv->tv_sec = x;
+	tv->tv_usec = (x - (double)tv->tv_sec) * 1000.0 * 1000.0 + 0.5;
+}
+
+/**
+ * Compute the difference of two time values.
+ *
+ * \param b Minuend.
+ * \param a Subtrahend.
+ * \param diff Result pointer.
+ *
+ * If \a diff is not \p NULL, it contains the absolute value |\a b - \a a| on
+ * return.
+ *
+ * \return If \a b < \a a, this function returns -1, otherwise it returns 1.
+ */
+int tv_diff(const struct timeval *b, const struct timeval *a, struct timeval *diff)
+{
+	int ret = 1;
+
+	if ((b->tv_sec < a->tv_sec) ||
+		((b->tv_sec == a->tv_sec) && (b->tv_usec < a->tv_usec))) {
+		const struct timeval *tmp = a;
+		a = b;
+		b = tmp;
+		ret = -1;
+	}
+	if (!diff)
+		return ret;
+	diff->tv_sec = b->tv_sec - a->tv_sec;
+	if (b->tv_usec < a->tv_usec) {
+		diff->tv_sec--;
+		diff->tv_usec = 1000 * 1000 - a->tv_usec + b->tv_usec;
+	} else
+		diff->tv_usec = b->tv_usec - a->tv_usec;
+	return ret;
+}
+
+/**
+ * Add two time values.
+ *
+ * \param a First addend.
+ * \param b Second addend.
+ * \param sum Contains the sum \a + \a b on return.
+ */
+void tv_add(const struct timeval *a, const struct timeval *b,
+	struct timeval *sum)
+{
+	sum->tv_sec = a->tv_sec + b->tv_sec;
+	if (a->tv_usec + b->tv_usec >= 1000 * 1000) {
+		sum->tv_sec++;
+		sum->tv_usec = a->tv_usec + b->tv_usec - 1000 * 1000;
+	} else
+		sum->tv_usec = a->tv_usec + b->tv_usec;
+}
+
+/**
+ * Compute integer multiple of given struct timeval.
+ *
+ * \param mult The integer value to multiply with.
+ * \param tv The timevalue to multiply.
+ *
+ * \param result Contains \a mult * \a tv on return.
+ */
+void tv_scale(const unsigned long mult, const struct timeval *tv,
+	struct timeval *result)
+{
+	result->tv_sec = mult * tv->tv_sec;
+	result->tv_sec += tv->tv_usec * mult / 1000 / 1000;
+	result->tv_usec = tv->tv_usec * mult % (1000 * 1000);
+}
+
+/**
+ * Compute a fraction of given struct timeval.
+ *
+ * \param divisor The integer value to divide by.
+ * \param tv The timevalue to divide.
+ * \param result Contains (1 / mult) * tv on return.
+ */
+void tv_divide(const unsigned long divisor, const struct timeval *tv,
+	struct timeval *result)
+{
+	uint64_t x = ((uint64_t)tv->tv_sec * 1000 * 1000 + tv->tv_usec) / divisor;
+
+	result->tv_sec = x / 1000 / 1000;
+	result->tv_usec = x % (1000 * 1000);
+}
+
+int64_t get_current_time(void)
+{
+	time_t now;
+	time(&now);
+	DSS_DEBUG_LOG(("now: %jd\n", (intmax_t)now));
+	return (int64_t)now;
+}