libs/libc/time: add gethrtime() support

Change-Id: I8882207d3a7e5062f70c7b4b95205361c71f8744
Signed-off-by: ligd <liguiding1@xiaomi.com>

include/sys/time.h

@@ -44,6 +44,7 @@
 
 #include <time.h>
 #include <sys/select.h>
+#include <sys/types.h>
 
 /****************************************************************************
  * Pre-processor Definitions
@@ -138,6 +139,8 @@
  * Public Type Definitions
  ****************************************************************************/
 
+typedef clock_t hrtime_t;
+
 /* struct timeval represents time as seconds plus microseconds */
 
 struct timeval
@@ -383,6 +386,19 @@ int setitimer(int which, FAR const struct itimerval *value,
 
 int utimes(FAR const char *path, const struct timeval times[2]);
 
+/****************************************************************************
+ * Name: gethrtime
+ *
+ * Description:
+ *   Get the current time
+ *
+ * Returned Value:
+ *   The current value of the system time in ns
+ *
+ ****************************************************************************/
+
+hrtime_t gethrtime(void);
+
 #undef EXTERN
 #if defined(__cplusplus)
 }

libs/libc/time/Make.defs

@@ -40,6 +40,7 @@ CSRCS += lib_strftime.c lib_calendar2utc.c lib_daysbeforemonth.c
 CSRCS += lib_gettimeofday.c lib_isleapyear.c lib_settimeofday.c lib_time.c
 CSRCS += lib_timespec_get.c lib_nanosleep.c lib_difftime.c lib_dayofweek.c
 CSRCS += lib_asctime.c lib_asctimer.c lib_ctime.c lib_ctimer.c
+CSRCS += lib_gethrtime.c
 
 ifdef CONFIG_LIBC_LOCALTIME
 CSRCS += lib_localtime.c

libs/libc/time/lib_gethrtime.c

@@ -0,0 +1,56 @@
+/****************************************************************************
+ * libs/libc/time/lib_gethrtime.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/time.h>
+#include <time.h>
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: gethrtime
+ *
+ * Description:
+ *   Get the current time
+ *
+ * Returned Value:
+ *   The current value of the system time in ns
+ *
+ ****************************************************************************/
+
+hrtime_t gethrtime(void)
+{
+  struct timespec ts;
+
+#ifdef CONFIG_CLOCK_MONOTONIC
+  clock_gettime(CLOCK_MONOTONIC, &ts);
+#else
+  clock_gettime(CLOCK_REALTIME, &ts);
+#endif
+
+  return (hrtime_t)1000000000 * ts.tv_sec + ts.tv_nsec;
+}