/*-
 * Copyright (c) 2018 Conrad Meyer <cem@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#define _WANT_KERNEL_ERRNO      1
#include <errno.h>

#include <lua.h>
#include "lauxlib.h"
#include "lerrno.h"

#ifndef nitems
#define nitems(x)       (sizeof((x)) / sizeof((x)[0]))
#endif

/*
 * Populated with:
 * $ egrep "^#define.E" sys/sys/errno.h | \
 *   awk '{ print "\tENTRY(" $2 ")," }' >> lerrno.c
 */
#define ENTRY(name)     { #name, name }
static const struct err_name_number {
        const char *err_name;
        int err_num;
} errnoconstants[] = {
        ENTRY(EPERM),
        ENTRY(ENOENT),
        ENTRY(ESRCH),
        ENTRY(EINTR),
        ENTRY(EIO),
        ENTRY(ENXIO),
        ENTRY(E2BIG),
        ENTRY(ENOEXEC),
        ENTRY(EBADF),
        ENTRY(ECHILD),
        ENTRY(EDEADLK),
        ENTRY(ENOMEM),
        ENTRY(EACCES),
        ENTRY(EFAULT),
        ENTRY(ENOTBLK),
        ENTRY(EBUSY),
        ENTRY(EEXIST),
        ENTRY(EXDEV),
        ENTRY(ENODEV),
        ENTRY(ENOTDIR),
        ENTRY(EISDIR),
        ENTRY(EINVAL),
        ENTRY(ENFILE),
        ENTRY(EMFILE),
        ENTRY(ENOTTY),
        ENTRY(ETXTBSY),
        ENTRY(EFBIG),
        ENTRY(ENOSPC),
        ENTRY(ESPIPE),
        ENTRY(EROFS),
        ENTRY(EMLINK),
        ENTRY(EPIPE),
        ENTRY(EDOM),
        ENTRY(ERANGE),
        ENTRY(EAGAIN),
        ENTRY(EWOULDBLOCK),
        ENTRY(EINPROGRESS),
        ENTRY(EALREADY),
        ENTRY(ENOTSOCK),
        ENTRY(EDESTADDRREQ),
        ENTRY(EMSGSIZE),
        ENTRY(EPROTOTYPE),
        ENTRY(ENOPROTOOPT),
        ENTRY(EPROTONOSUPPORT),
        ENTRY(ESOCKTNOSUPPORT),
        ENTRY(EOPNOTSUPP),
        ENTRY(ENOTSUP),
        ENTRY(EPFNOSUPPORT),
        ENTRY(EAFNOSUPPORT),
        ENTRY(EADDRINUSE),
        ENTRY(EADDRNOTAVAIL),
        ENTRY(ENETDOWN),
        ENTRY(ENETUNREACH),
        ENTRY(ENETRESET),
        ENTRY(ECONNABORTED),
        ENTRY(ECONNRESET),
        ENTRY(ENOBUFS),
        ENTRY(EISCONN),
        ENTRY(ENOTCONN),
        ENTRY(ESHUTDOWN),
        ENTRY(ETOOMANYREFS),
        ENTRY(ETIMEDOUT),
        ENTRY(ECONNREFUSED),
        ENTRY(ELOOP),
        ENTRY(ENAMETOOLONG),
        ENTRY(EHOSTDOWN),
        ENTRY(EHOSTUNREACH),
        ENTRY(ENOTEMPTY),
        ENTRY(EPROCLIM),
        ENTRY(EUSERS),
        ENTRY(EDQUOT),
        ENTRY(ESTALE),
        ENTRY(EREMOTE),
        ENTRY(EBADRPC),
        ENTRY(ERPCMISMATCH),
        ENTRY(EPROGUNAVAIL),
        ENTRY(EPROGMISMATCH),
        ENTRY(EPROCUNAVAIL),
        ENTRY(ENOLCK),
        ENTRY(ENOSYS),
        ENTRY(EFTYPE),
        ENTRY(EAUTH),
        ENTRY(ENEEDAUTH),
        ENTRY(EIDRM),
        ENTRY(ENOMSG),
        ENTRY(EOVERFLOW),
        ENTRY(ECANCELED),
        ENTRY(EILSEQ),
        ENTRY(ENOATTR),
        ENTRY(EDOOFUS),
        ENTRY(EBADMSG),
        ENTRY(EMULTIHOP),
        ENTRY(ENOLINK),
        ENTRY(EPROTO),
        ENTRY(ENOTCAPABLE),
        ENTRY(ECAPMODE),
        ENTRY(ENOTRECOVERABLE),
        ENTRY(EOWNERDEAD),
        ENTRY(EINTEGRITY),
        ENTRY(ELAST),
        ENTRY(ERESTART),
        ENTRY(EJUSTRETURN),
        ENTRY(ENOIOCTL),
        ENTRY(EDIRIOCTL),
        ENTRY(ERELOOKUP),
};
#undef ENTRY

static void
lerrno_register(lua_State *L)
{
        size_t i;

        for (i = 0; i < nitems(errnoconstants); i++) {
                lua_pushinteger(L, errnoconstants[i].err_num);
                lua_setfield(L, -2, errnoconstants[i].err_name);
        }
}

static const struct luaL_Reg errnolib[] = {
        /* Extra bogus entry required by luaL_newlib API */
        { NULL, NULL },
};

int
luaopen_errno(lua_State *L)
{
        luaL_newlib(L, errnolib);
        lerrno_register(L);
        return 1;
}