/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
│                                                                              │
│ Permission to use, copy, modify, and/or distribute this software for         │
│ any purpose with or without fee is hereby granted, provided that the         │
│ above copyright notice and this permission notice appear in all copies.      │
│                                                                              │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
│ PERFORMANCE OF THIS SOFTWARE.                                                │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/strace.internal.h"
#include "libc/intrin/describeflags.internal.h"

int sys_sched_rr_get_interval(int, struct timespec *) hidden;

/**
 * Returns round-robin `SCHED_RR` quantum for `pid`.
 *
 * @param pid is id of process (where 0 is same as getpid())
 * @param tp receives output interval
 * @return 0 on success, or -1 w/ errno
 * @error ENOSYS if not Linux or FreeBSD
 * @error EFAULT if `tp` memory is invalid
 * @error EINVAL if invalid `pid`
 * @error ESRCH if could not find `pid`
 */
int sched_rr_get_interval(int pid, struct timespec *tp) {
  int rc;
  rc = sys_sched_rr_get_interval(pid, tp);
  STRACE("sched_rr_get_interval(%d, [%s]) → %d% m", pid,
         DescribeTimespec(rc, tp), rc);
  return rc;
}