/* Copyright (c) 2014, Michael Santos <michael.santos@gmail.com>
 *
 * 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 "alcove.h"
#include "alcove_call.h"

#include "alcove_prio_constants.h"

/*
 * getpriority(2)
 */
ssize_t alcove_sys_getpriority(alcove_state_t *ap, const char *arg, size_t len,
                               char *reply, size_t rlen) {
  int index = 0;
  int rindex = 0;

  int which = 0;
  int who = 0;
  int prio = 0;

  UNUSED(ap);

  /* which */
  switch (
      alcove_decode_constant(arg, len, &index, &which, alcove_prio_constants)) {
  case 0:
    break;
  case 1:
    return alcove_mk_error(reply, rlen, "enotsup");
  default:
    return -1;
  }

  /* who */
  switch (
      alcove_decode_constant(arg, len, &index, &who, alcove_prio_constants)) {
  case 0:
    break;
  case 1:
    return alcove_mk_error(reply, rlen, "enotsup");
  default:
    return -1;
  }

  errno = 0;
  prio = getpriority(which, who);

  if (errno != 0)
    return alcove_mk_errno(reply, rlen, errno);

  ALCOVE_OK(reply, rlen, &rindex,
            alcove_encode_long(reply, rlen, &rindex, prio));

  return rindex;
}