/*-*- 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 2020 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/internal.h"
#include "libc/intrin/fds.h"
#include "libc/dce.h"
#include "libc/intrin/strace.h"
#include "libc/sock/internal.h"
#include "libc/sock/sock.h"
#include "libc/sock/syscall_fd.internal.h"
#include "libc/sysv/errfuns.h"

/**
 * Disables sends or receives on a socket, without closing.
 *
 * @param fd is the open file descriptor for the socket
 * @param how can be SHUT_RD, SHUT_WR, or SHUT_RDWR
 * @return 0 on success or -1 on error
 * @asyncsignalsafe
 */
int shutdown(int fd, int how) {
  int rc;
  if (fd < g_fds.n && g_fds.p[fd].kind == kFdZip) {
    rc = enotsock();
  } else if (!IsWindows()) {
    rc = sys_shutdown(fd, how);
  } else if (!__isfdopen(fd)) {
    rc = ebadf();
  } else if (__isfdkind(fd, kFdSocket)) {
    rc = sys_shutdown_nt(&g_fds.p[fd], how);
  } else {
    rc = enotsock();
  }
  STRACE("shutdown(%d, %d) -> %d% lm", fd, how, rc);
  return rc;
}
