X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=include%2Fbabeltrace%2Fclock-internal.h;h=4bd46111c8ab6ab0df757ef97426e75dc94bd690;hb=61cf588beae752e5ddfc60b6b5310f769ac9e852;hp=6fbc7c32c95143ba2e8ef455a2c65bc358e89432;hpb=bb919dd077169b5ee049ba3fc82f8555648cb22e;p=babeltrace.git

diff --git a/include/babeltrace/clock-internal.h b/include/babeltrace/clock-internal.h
index 6fbc7c32..4bd46111 100644
--- a/include/babeltrace/clock-internal.h
+++ b/include/babeltrace/clock-internal.h
@@ -20,6 +20,14 @@
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
  */
 
 static inline
@@ -34,4 +42,18 @@ uint64_t clock_cycles_to_ns(struct ctf_clock *clock, uint64_t cycles)
 	}
 }
 
+/*
+ * Note: if using a frequency different from 1GHz for clock->offset, it
+ * is recommended to express the seconds in offset_s, otherwise there
+ * will be a loss of precision caused by the limited size of the double
+ * mantissa.
+ * This offset can be negative.
+ */
+static inline
+int64_t clock_offset_ns(struct ctf_clock *clock)
+{
+	return clock->offset_s * 1000000000ULL
+			+ clock_cycles_to_ns(clock, clock->offset);
+}
+
 #endif /* _BABELTRACE_CLOCK_INTERNAL_H */