Changeset 7f9d97f3 in mainline for uspace/lib/c/generic/time.c

Timestamp:

2015-03-14T21:48:01Z (9 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

270bf4f

Parents:

c0c38c7c

Message:

Make gettimeofday() return the actual microseconds.

Enhance struct tm to also have a field to hold microseconds and make
sure that this information propagates from the RTC driver.

File:

• uspace/lib/c/generic/time.c (modified) (16 diffs)

uspace/lib/c/generic/time.c

@@ -59 +59 @@
 #define MINS_PER_HOUR  60
 #define SECS_PER_MIN   60
+#define USECS_PER_SEC  1000000
 #define MINS_PER_DAY   (MINS_PER_HOUR * HOURS_PER_DAY)
 #define SECS_PER_HOUR  (SECS_PER_MIN * MINS_PER_HOUR)
@@ -252 +253 @@
  * Optionally add specified amount of seconds.
  *
- * @param tm      Broken-down time to normalize.
- * @param sec_add Seconds to add.
+ * @param tm Broken-down time to normalize.
+ * @param tv Timeval to add.
  *
  * @return 0 on success, -1 on overflow
  *
  */
-static int normalize_time(struct tm *tm, time_t sec_add)
+static int normalize_tm_tv(struct tm *tm, const struct timeval *tv)
 {
         // TODO: DST correction
         
         /* Set initial values. */
-        time_t sec = tm->tm_sec + sec_add;
+        time_t usec = tm->tm_usec + tv->tv_usec;
+        time_t sec = tm->tm_sec + tv->tv_sec;
         time_t min = tm->tm_min;
         time_t hour = tm->tm_hour;
@@ -271 +273 @@
         
         /* Adjust time. */
+        sec += floor_div(usec, USECS_PER_SEC);
+        usec = floor_mod(usec, USECS_PER_SEC);
         min += floor_div(sec, SECS_PER_MIN);
         sec = floor_mod(sec, SECS_PER_MIN);
@@ -319 +323 @@
         
         /* And put the values back to the struct. */
+        tm->tm_usec = (int) usec;
         tm->tm_sec = (int) sec;
         tm->tm_min = (int) min;
@@ -335 +340 @@
 }
 
+static int normalize_tm_time(struct tm *tm, time_t time)
+{
+        struct timeval tv = {
+                .tv_sec = time,
+                .tv_usec = 0
+        };
+
+        return normalize_tm_tv(tm, &tv);
+}
+
+
 /** Which day the week-based year starts on.
  *
@@ -442 +458 @@
 }
 
+static void tv_normalize(struct timeval *tv)
+{
+        while (tv->tv_usec > USECS_PER_SEC) {
+                tv->tv_sec++;
+                tv->tv_usec -= USECS_PER_SEC;
+        }
+        while (tv->tv_usec < 0) {
+                tv->tv_sec--;
+                tv->tv_usec += USECS_PER_SEC;
+        }
+}
+
 /** Add microseconds to given timeval.
  *
@@ -448 +476 @@
  *
  */
-void tv_add(struct timeval *tv, suseconds_t usecs)
-{
-        tv->tv_sec += usecs / 1000000;
-        tv->tv_usec += usecs % 1000000;
-        
-        if (tv->tv_usec > 1000000) {
-                tv->tv_sec++;
-                tv->tv_usec -= 1000000;
-        }
-}
-
-/** Subtract two timevals.
+void tv_add_diff(struct timeval *tv, suseconds_t usecs)
+{
+        tv->tv_sec += usecs / USECS_PER_SEC;
+        tv->tv_usec += usecs % USECS_PER_SEC;
+        tv_normalize(tv);
+}
+
+/** Add two timevals.
  *
  * @param tv1 First timeval.
  * @param tv2 Second timeval.
+ */
+void tv_add(struct timeval *tv1, struct timeval *tv2)
+{
+        tv1->tv_sec += tv2->tv_sec;
+        tv1->tv_usec += tv2->tv_usec;
+        tv_normalize(tv1);
+}
+
+/** Subtract two timevals.
+ *
+ * @param tv1 First timeval.
+ * @param tv2 Second timeval.
  *
  * @return Difference between tv1 and tv2 (tv1 - tv2) in
@@ -468 +504 @@
  *
  */
-suseconds_t tv_sub(struct timeval *tv1, struct timeval *tv2)
+suseconds_t tv_sub_diff(struct timeval *tv1, struct timeval *tv2)
 {
         return (tv1->tv_usec - tv2->tv_usec) +
-            ((tv1->tv_sec - tv2->tv_sec) * 1000000);
+            ((tv1->tv_sec - tv2->tv_sec) * USECS_PER_SEC);
+}
+
+/** Subtract two timevals.
+ *
+ * @param tv1 First timeval.
+ * @param tv2 Second timeval.
+ *
+ */
+void tv_sub(struct timeval *tv1, struct timeval *tv2)
+{
+        tv1->tv_sec -= tv2->tv_sec;
+        tv1->tv_usec -= tv2->tv_usec;
+        tv_normalize(tv1);
 }
 
@@ -573 +622 @@
                 goto fallback;
         
-        tv->tv_usec = 0;
+        tv->tv_usec = time.tm_usec;
         tv->tv_sec = mktime(&time);
         
@@ -689 +738 @@
         // TODO: detect overflow
         
-        normalize_time(tm, 0);
+        normalize_tm_time(tm, 0);
         return secs_since_epoch(tm);
 }
@@ -944 +993 @@
         
         /* Set result to epoch. */
+        result->tm_usec = 0;
         result->tm_sec = 0;
         result->tm_min = 0;
@@ -951 +1001 @@
         result->tm_year = 70; /* 1970 */
         
-        if (normalize_time(result, time) == -1)
+        if (normalize_tm_time(result, time) == -1)
                 return EOVERFLOW;
         
@@ -1014 +1064 @@
  * Time is expressed relative to the user's specified timezone.
  *
- * @param timer  Time to convert.
+ * @param tv     Timeval to convert.
  * @param result Structure to store the result to.
  *
@@ -1020 +1070 @@
  *
  */
-int time_local2tm(const time_t time, struct tm *restrict result)
+int time_tv2tm(const struct timeval *tv, struct tm *restrict result)
 {
         // TODO: Deal with timezones.
@@ -1026 +1076 @@
         
         /* Set result to epoch. */
+        result->tm_usec = 0;
         result->tm_sec = 0;
         result->tm_min = 0;
@@ -1033 +1084 @@
         result->tm_year = 70; /* 1970 */
         
-        if (normalize_time(result, time) == -1)
+        if (normalize_tm_tv(result, tv) == -1)
                 return EOVERFLOW;
         
         return EOK;
+}
+
+/** Converts a time value to a broken-down local time.
+ *
+ * Time is expressed relative to the user's specified timezone.
+ *
+ * @param timer  Time to convert.
+ * @param result Structure to store the result to.
+ *
+ * @return EOK on success or a negative error code.
+ *
+ */
+int time_local2tm(const time_t time, struct tm *restrict result)
+{
+        struct timeval tv = {
+                .tv_sec = time,
+                .tv_usec = 0
+        };
+
+        return time_tv2tm(&tv, result);
 }