/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8                               :vi │
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2021 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/syscall-sysv.internal.h"
#include "libc/dce.h"
#include "libc/intrin/describeflags.h"
#include "libc/intrin/directmap.h"
#include "libc/intrin/strace.h"
#include "libc/runtime/runtime.h"
#include "libc/runtime/syslib.internal.h"

/**
 * Unmaps memory directly with system.
 *
 * This function bypasses memtrack. Therefore it won't work on Windows,
 * but it works on everything else including bare metal.
 *
 * @asyncsignalsafe
 */
int sys_munmap(void *p, size_t n) {
  int rc;
  if (IsXnuSilicon()) {
    rc = _sysret(__syslib->__munmap(p, n));
  } else if (IsMetal()) {
    rc = sys_munmap_metal(p, n);
  } else {
    rc = __sys_munmap(p, n);
  }
  if (!rc)
    __virtualsize -= n;
  KERNTRACE("sys_munmap(%p, %'zu) → %d", p, n, rc);
  return rc;
}