#define _GNU_SOURCE
#include <fcntl.h>
#include <stdarg.h>
#include <errno.h>
#include "syscall.h"
#include "libc.h"

int fcntl(int fd, int cmd, ...) {
  unsigned long arg;
  va_list ap;
  va_start(ap, cmd);
  arg = va_arg(ap, unsigned long);
  va_end(ap);
  if (cmd == F_SETFL)
    arg |= O_LARGEFILE;
  if (cmd == F_SETLKW)
    return syscall_cp(SYS_fcntl, fd, cmd, (void*)arg);
  if (cmd == F_GETOWN) {
    struct f_owner_ex ex;
    int ret = __syscall(SYS_fcntl, fd, F_GETOWN_EX, &ex);
    if (ret == -EINVAL)
      return __syscall(SYS_fcntl, fd, cmd, (void*)arg);
    if (ret)
      return __syscall_ret(ret);
    return ex.type == F_OWNER_PGRP ? -ex.pid : ex.pid;
  }
  if (cmd == F_DUPFD_CLOEXEC) {
    int ret = __syscall(SYS_fcntl, fd, F_DUPFD_CLOEXEC, arg);
    if (ret != -EINVAL) {
      if (ret >= 0)
        __syscall(SYS_fcntl, ret, F_SETFD, FD_CLOEXEC);
      return __syscall_ret(ret);
    }
    ret = __syscall(SYS_fcntl, fd, F_DUPFD_CLOEXEC, 0);
    if (ret != -EINVAL) {
      if (ret >= 0)
        __syscall(SYS_close, ret);
      return __syscall_ret(-EINVAL);
    }
    ret = __syscall(SYS_fcntl, fd, F_DUPFD, arg);
    if (ret >= 0)
      __syscall(SYS_fcntl, ret, F_SETFD, FD_CLOEXEC);
    return __syscall_ret(ret);
  }
  switch (cmd) {
    case F_SETLK:
    case F_GETLK:
    case F_GETOWN_EX:
    case F_SETOWN_EX:
      return syscall(SYS_fcntl, fd, cmd, (void*)arg);
    default:
      return syscall(SYS_fcntl, fd, cmd, arg);
  }
}