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Diffstat (limited to 'sysdeps/mach/clock_nanosleep.c')
-rw-r--r--sysdeps/mach/clock_nanosleep.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/sysdeps/mach/clock_nanosleep.c b/sysdeps/mach/clock_nanosleep.c
new file mode 100644
index 0000000000..6dc67d649f
--- /dev/null
+++ b/sysdeps/mach/clock_nanosleep.c
@@ -0,0 +1,111 @@
+/* clock_nanosleep - high-resolution sleep with specifiable clock.
+ Copyright (C) 2002-2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <mach.h>
+#include <time.h>
+#include <unistd.h>
+#include <posix-timer.h>
+#include <shlib-compat.h>
+
+static int
+nanosleep_call (const struct timespec *req, struct timespec *rem)
+{
+ mach_port_t recv;
+ struct timespec before;
+ error_t err;
+
+ const mach_msg_timeout_t ms
+ = req->tv_sec * 1000
+ + (req->tv_nsec + 999999) / 1000000;
+
+ recv = __mach_reply_port ();
+
+ if (rem != NULL)
+ __clock_gettime (CLOCK_REALTIME, &before);
+
+ err = __mach_msg (NULL, MACH_RCV_MSG|MACH_RCV_TIMEOUT|MACH_RCV_INTERRUPT,
+ 0, 0, recv, ms, MACH_PORT_NULL);
+ __mach_port_destroy (mach_task_self (), recv);
+ if (err == EMACH_RCV_INTERRUPTED)
+ {
+ if (rem != NULL)
+ {
+ struct timespec after, elapsed;
+ __clock_gettime (CLOCK_REALTIME, &after);
+ timespec_sub (&elapsed, &after, &before);
+ timespec_sub (rem, req, &elapsed);
+ }
+
+ return EINTR;
+ }
+
+ return 0;
+}
+
+int
+__clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
+ struct timespec *rem)
+{
+ if (clock_id != CLOCK_REALTIME
+ || !valid_nanoseconds (req->tv_nsec)
+ || (flags != 0 && flags != TIMER_ABSTIME))
+ return EINVAL;
+
+ struct timespec now;
+
+ /* If we got an absolute time, remap it. */
+ if (flags == TIMER_ABSTIME)
+ {
+ long int nsec;
+ long int sec;
+
+ /* Make sure we use safe data types. */
+ assert (sizeof (sec) >= sizeof (now.tv_sec));
+
+ /* Get the current time for this clock. */
+ if (__clock_gettime (clock_id, &now) != 0)
+ return errno;
+
+ /* Compute the difference. */
+ nsec = req->tv_nsec - now.tv_nsec;
+ sec = req->tv_sec - now.tv_sec - (nsec < 0);
+ if (sec < 0)
+ /* The time has already elapsed. */
+ return 0;
+
+ now.tv_sec = sec;
+ now.tv_nsec = nsec + (nsec < 0 ? 1000000000 : 0);
+
+ /* From now on this is our time. */
+ req = &now;
+
+ /* Make sure we are not modifying the struct pointed to by REM. */
+ rem = NULL;
+ }
+
+ return nanosleep_call (req, rem);
+}
+libc_hidden_def (__clock_nanosleep)
+versioned_symbol (libc, __clock_nanosleep, clock_nanosleep, GLIBC_2_17);
+/* clock_nanosleep moved to libc in version 2.17;
+ old binaries may expect the symbol version it had in librt. */
+#if SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_17)
+strong_alias (__clock_nanosleep, __clock_nanosleep_2);
+compat_symbol (libc, __clock_nanosleep_2, clock_nanosleep, GLIBC_2_2);
+#endif