X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fbasic%2Ftime-util.h;h=a6df932ad2040cbfabe6bd1b2514749d6451a39f;hb=401d49ceb8a3ccc6a4bae6279ca2cf4dc22e6671;hp=aa600099337cb06f40d427b81eb73ee68b721c47;hpb=d72545b2a0c29e5844c508101cd4720c356193b4;p=elogind.git

diff --git a/src/basic/time-util.h b/src/basic/time-util.h
index aa6000993..a6df932ad 100644
--- a/src/basic/time-util.h
+++ b/src/basic/time-util.h
@@ -29,8 +29,10 @@
 typedef uint64_t usec_t;
 typedef uint64_t nsec_t;
 
-#define NSEC_FMT "%" PRIu64
-#define USEC_FMT "%" PRIu64
+#define PRI_NSEC PRIu64
+#define PRI_USEC PRIu64
+#define NSEC_FMT "%" PRI_NSEC
+#define USEC_FMT "%" PRI_USEC
 
 #include "macro.h"
 
@@ -115,6 +117,9 @@ static inline bool triple_timestamp_is_set(triple_timestamp *ts) {
 usec_t triple_timestamp_by_clock(triple_timestamp *ts, clockid_t clock);
 
 usec_t timespec_load(const struct timespec *ts) _pure_;
+#if 0 /// UNNEEDED by elogind
+nsec_t timespec_load_nsec(const struct timespec *ts) _pure_;
+#endif // 0
 struct timespec *timespec_store(struct timespec *ts, usec_t u);
 
 usec_t timeval_load(const struct timeval *tv) _pure_;
@@ -186,15 +191,30 @@ static inline usec_t usec_add(usec_t a, usec_t b) {
         return c;
 }
 
-static inline usec_t usec_sub(usec_t timestamp, int64_t delta) {
-        if (delta < 0)
-                return usec_add(timestamp, (usec_t) (-delta));
+static inline usec_t usec_sub_unsigned(usec_t timestamp, usec_t delta) {
 
         if (timestamp == USEC_INFINITY) /* Make sure infinity doesn't degrade */
                 return USEC_INFINITY;
-
-        if (timestamp < (usec_t) delta)
+        if (timestamp < delta)
                 return 0;
 
         return timestamp - delta;
 }
+
+static inline usec_t usec_sub_signed(usec_t timestamp, int64_t delta) {
+        if (delta < 0)
+                return usec_add(timestamp, (usec_t) (-delta));
+        else
+                return usec_sub_unsigned(timestamp, (usec_t) delta);
+}
+
+#if SIZEOF_TIME_T == 8
+/* The last second we can format is 31. Dec 9999, 1s before midnight, because otherwise we'd enter 5 digit year
+ * territory. However, since we want to stay away from this in all timezones we take one day off. */
+#define USEC_TIMESTAMP_FORMATTABLE_MAX ((usec_t) 253402214399000000)
+#elif SIZEOF_TIME_T == 4
+/* With a 32bit time_t we can't go beyond 2038... */
+#define USEC_TIMESTAMP_FORMATTABLE_MAX ((usec_t) 2147483647000000)
+#else
+#error "Yuck, time_t is neither 4 not 8 bytes wide?"
+#endif