[libc-commits] [libc] [libc] move abs_timesout and monotonicity out of linux dir (PR #167719)

[via libc-commits]

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@@ -16,6 +16,28 @@
 namespace LIBC_NAMESPACE_DECL {
 namespace internal {
 
+/**
+ * @brief Convert a timespec value from one clock domain to another.
+ *
+ * The function takes a timestamp that is expressed in terms of the clock
+ * identified by param from and returns an equivalent timestamp expressed
+ * in terms of the clock identified by param to.
+ *
+ * Internally it obtains the current time of both clocks with
+ * clock_gettime, then subtracts the source clock’s value and
+ * adds the target clock’s value. The result is normalised so that
+ * the nanoseconds field is always in the range [0, 1 s).
+ *
+ * This is useful, for example, for converting a value obtained from
+ * CLOCK_MONOTONIC to CLOCK_REALTIME (or vice‑versa) so that the
+ * timestamp can be displayed to a user or stored in a format that
+ * is independent of the original clock domain.
+ *
+ * @param input The timestamp to convert
+ * @param from Clock ID of the original timestamp (e.g. CLOCK_MONOTONIC).
+ * @param to Clock ID of the desired timestamp (e.g. CLOCK_REALTIME).
+ * @return The converted timespec
+ */
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lntue wrote:

Can this comment use C++'s `//` to match other files' style?

https://github.com/llvm/llvm-project/pull/167719