/* Copyright (c) 2015, 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 <fcntl.h>

#include "alcove_fcntl_constants.h"

typedef struct {
  u_char type;
  int arg;
  char data[MAXMSGLEN];
  size_t len;
} alcove_fcntl_arg_t;

enum { ALCOVE_FCNTL_INT, ALCOVE_FCNTL_CSTRUCT, ALCOVE_FCNTL_BINARY };

/*
 * fcntl(2)
 *
 */
ssize_t alcove_sys_fcntl(alcove_state_t *ap, const char *arg, size_t len,
                         char *reply, size_t rlen) {
  int index = 0;
  int rindex = 0;
  int type = 0;
  int arity = 0;

  int fd = 0;
  int cmd = 0;
  alcove_fcntl_arg_t argp = {0};

  int rv = 0;

  UNUSED(ap);

  /* fd */
  if (alcove_decode_int(arg, len, &index, &fd) < 0)
    return -1;

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

  /* argp */
  if (alcove_get_type(arg, len, &index, &type, &arity) < 0)
    return -1;

  switch (type) {
  case ERL_SMALL_INTEGER_EXT:
  case ERL_INTEGER_EXT:
    argp.type = ALCOVE_FCNTL_INT;
    if (alcove_decode_int(arg, len, &index, &argp.arg) < 0)
      return -1;

    break;

  default:
    return -1;
  }

  rv = fcntl(fd, cmd, argp.arg);

  if (rv < 0)
    return alcove_mk_errno(reply, rlen, errno);

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

  return rindex;
}