support: Provide xclock_settime test helper function

The xclock_settime is a wrapper function on the clock_settime syscall
to be used in the test code.

It checks if the GLIBC_TEST_ALLOW_TIME_SETTING env variable is defined
in the environment in which test is executed. If it is not - the test
ends as unsupported. Otherwise, the clock-settime is executed and return
value is assessed.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/support/xtime.h b/support/xtime.h
index 2482837dee..b4ac3b59e2 100644
--- a/support/xtime.h
+++ b/support/xtime.h
@@ -23,10 +23,15 @@
 
 __BEGIN_DECLS
 
+/* Name of the env variable, which indicates if it is possible to
+   adjust time on target machine.  */
+#define SETTIME_ENV_NAME "GLIBC_TEST_ALLOW_TIME_SETTING"
+
 /* The following functions call the corresponding libc functions and
    terminate the process on error.  */
 
 void xclock_gettime (clockid_t clock, struct timespec *ts);
+void xclock_settime (clockid_t clock, const struct timespec *ts);
 
 /* This helper can often simplify tests by avoiding an explicit
    variable declaration or allowing that declaration to be const. */