diff options
Diffstat (limited to 'sysdeps/mach/clock_nanosleep.c')
-rw-r--r-- | sysdeps/mach/clock_nanosleep.c | 111 |
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 |