cosmopolitan/libc/calls/sched_setparam.c

/*-*- 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/sched-sysv.internal.h"
#include "libc/calls/struct/sched_param.h"
#include "libc/calls/struct/sched_param.internal.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/intrin/strace.internal.h"
#include "libc/sysv/errfuns.h"

/**
 * Sets scheduler policy parameter.
 *
 * @return 0 on success, or -1 w/ errno
 * @raise ENOSYS on XNU, Windows, OpenBSD
 * @vforksafe
 */
int sched_setparam(int pid, const struct sched_param *param) {
  int rc, policy;
  struct sched_param p;
  if (!param || (IsAsan() && !__asan_is_valid(param, sizeof(*param)))) {
    rc = efault();
  } else if (IsNetbsd()) {
    if ((rc = policy = sys_sched_getscheduler_netbsd(pid, &p)) != -1) {
      rc = sys_sched_setparam_netbsd(pid, P_ALL_LWPS, policy, param);
    }
  } else {
    rc = sys_sched_setparam(pid, param);
  }
  STRACE("sched_setparam(%d, %s) → %d% m", pid, DescribeSchedParam(param), rc);
  return rc;
}