Add flua to the base system, install to /usr/libexec

FreeBSDlua ("flua") is a FreeBSD-private lua, flavored with whatever
extensions we need for base system operations. We currently support a subset
of lfs and lposix that are used in the rewrite of makesyscall.sh into lua,
added in r354786.

flua is intentionally written such that one can install standard lua and
some set of lua modules from ports and achieve the same effect.

linit_flua is a copy of linit.c from contrib/lua with lfs and lposix added
in. This is similar to what we do in stand/. linit.c has been renamed to
make it clear that this has flua-specific bits.

luaconf has been slightly obfuscated to make extensions more difficult. Part
of the problem is that flua is already hard enough to use as a bootstrap
tool because it's not in PATH- attempting to do extension loading would
require a special bootstrap version of flua with paths changed to protect
the innocent.

src.lua.mk has been added to make it easy for in-tree stuff to find flua,
whether it's bootstrap-flua or relying on PATH frobbing by Makefile.inc1.

Reviewed by:	brooks, emaste (both earlier version), imp
Differential Revision:	https://reviews.freebsd.org/D21893

3 files changed, 4 insertions, 376 deletions

diff --git a/stand/liblua/Makefile b/stand/liblua/Makefile
index 49ed02709299..9693f579f801 100644
--- a/stand/liblua/Makefile
+++ b/stand/liblua/Makefile
@@ -23,7 +23,10 @@ SRCS+=	lauxlib.c lbaselib.c lstrlib.c loadlib.c
 #SRCS+=	lbitlib.c liolib.c lmathlib.c loslib.c ltablib.c
 
 # Our utilities.
-SRCS+=	lerrno.c lfs.c lstd.c lutils.c
+SRCS+=	lerrno.c lstd.c lutils.c
+
+.PATH:	${FLUASRC}/modules
+SRCS+=	lfs.c
 
 WARNS=	3
 
diff --git a/stand/liblua/lfs.c b/stand/liblua/lfs.c
deleted file mode 100644
index bc557b96a6ef..000000000000
--- a/stand/liblua/lfs.c
+++ /dev/null
@@ -1,342 +0,0 @@
-/*-
- * 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.
- *
- * Portions derived from https://github.com/keplerproject/luafilesystem under
- * the terms of the MIT license:
- *
- * Copyright (c) 2003-2014 Kepler Project.
- *
- * Permission is hereby granted, free of charge, to any person
- * obtaining a copy of this software and associated documentation
- * files (the "Software"), to deal in the Software without
- * restriction, including without limitation the rights to use, copy,
- * modify, merge, publish, distribute, sublicense, and/or sell copies
- * of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be
- * included in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
- * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
- * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
-#include <lua.h>
-#include "lauxlib.h"
-#include "lfs.h"
-#include "lstd.h"
-#include "lutils.h"
-#include "bootstrap.h"
-
-#ifndef nitems
-#define	nitems(x)	(sizeof((x)) / sizeof((x)[0]))
-#endif
-
-/*
- * The goal is to emulate a subset of the upstream Lua FileSystem library, as
- * faithfully as possible in the boot environment.  Only APIs that seem useful
- * need to emulated.
- *
- * Example usage:
- *
- *     for file in lfs.dir("/boot") do
- *         print("\t"..file)
- *     end
- *
- * Prints:
- *     .
- *     ..
- * (etc.)
- *
- * The other available API is lfs.attributes(), which functions somewhat like
- * stat(2) and returns a table of values.  Example code:
- *
- *     attrs, errormsg, errorcode = lfs.attributes("/boot")
- *     if attrs == nil then
- *         print(errormsg)
- *         return errorcode
- *     end
- *
- *     for k, v in pairs(attrs) do
- *         print(k .. ":\t" .. v)
- *     end
- *     return 0
- *
- * Prints (on success):
- *     gid:    0
- *     change: 140737488342640
- *     mode:   directory
- *     rdev:   0
- *     ino:    4199275
- *     dev:    140737488342544
- *     modification:   140737488342576
- *     size:   512
- *     access: 140737488342560
- *     permissions:    755
- *     nlink:  58283552
- *     uid:    1001
- */
-
-#define DIR_METATABLE "directory iterator metatable"
-
-static int
-lua_dir_iter_next(lua_State *L)
-{
-	struct dirent *entry;
-	DIR *dp, **dpp;
-
-	dpp = (DIR **)luaL_checkudata(L, 1, DIR_METATABLE);
-	dp = *dpp;
-	luaL_argcheck(L, dp != NULL, 1, "closed directory");
-
-	entry = readdirfd(dp->fd);
-	if (entry == NULL) {
-		closedir(dp);
-		*dpp = NULL;
-		return 0;
-	}
-
-	lua_pushstring(L, entry->d_name);
-	return 1;
-}
-
-static int
-lua_dir_iter_close(lua_State *L)
-{
-	DIR *dp, **dpp;
-
-	dpp = (DIR **)lua_touserdata(L, 1);
-	dp = *dpp;
-	if (dp == NULL)
-		return 0;
-
-	closedir(dp);
-	*dpp = NULL;
-	return 0;
-}
-
-static int
-lua_dir(lua_State *L)
-{
-	const char *path;
-	DIR *dp;
-
-	if (lua_gettop(L) != 1) {
-		lua_pushnil(L);
-		return 1;
-	}
-
-	path = luaL_checkstring(L, 1);
-	dp = opendir(path);
-	if (dp == NULL) {
-		lua_pushnil(L);
-		return 1;
-	}
-
-	lua_pushcfunction(L, lua_dir_iter_next);
-	*(DIR **)lua_newuserdata(L, sizeof(DIR **)) = dp;
-	luaL_getmetatable(L, DIR_METATABLE);
-	lua_setmetatable(L, -2);
-	return 2;
-}
-
-static void
-register_metatable(lua_State *L)
-{
-	/*
-	 * Create so-called metatable for iterator object returned by
-	 * lfs.dir().
-	 */
-	luaL_newmetatable(L, DIR_METATABLE);
-
-	lua_newtable(L);
-	lua_pushcfunction(L, lua_dir_iter_next);
-	lua_setfield(L, -2, "next");
-	lua_pushcfunction(L, lua_dir_iter_close);
-	lua_setfield(L, -2, "close");
-
-	/* Magically associate anonymous method table with metatable. */
-	lua_setfield(L, -2, "__index");
-	/* Implement magic destructor method */
-	lua_pushcfunction(L, lua_dir_iter_close);
-	lua_setfield(L, -2, "__gc");
-
-	lua_pop(L, 1);
-}
-
-#define PUSH_INTEGER(lname, stname)				\
-static void							\
-push_st_ ## lname (lua_State *L, struct stat *sb)		\
-{								\
-	lua_pushinteger(L, (lua_Integer)sb->st_ ## stname);	\
-}
-PUSH_INTEGER(dev, dev)
-PUSH_INTEGER(ino, ino)
-PUSH_INTEGER(nlink, nlink)
-PUSH_INTEGER(uid, uid)
-PUSH_INTEGER(gid, gid)
-PUSH_INTEGER(rdev, rdev)
-PUSH_INTEGER(access, atime)
-PUSH_INTEGER(modification, mtime)
-PUSH_INTEGER(change, ctime)
-PUSH_INTEGER(size, size)
-#undef PUSH_INTEGER
-
-static void
-push_st_mode(lua_State *L, struct stat *sb)
-{
-	const char *mode_s;
-	mode_t mode;
-
-	mode = (sb->st_mode & S_IFMT);
-	if (S_ISREG(mode))
-		mode_s = "file";
-	else if (S_ISDIR(mode))
-		mode_s = "directory";
-	else if (S_ISLNK(mode))
-		mode_s = "link";
-	else if (S_ISSOCK(mode))
-		mode_s = "socket";
-	else if (S_ISFIFO(mode))
-		mode_s = "fifo";
-	else if (S_ISCHR(mode))
-		mode_s = "char device";
-	else if (S_ISBLK(mode))
-		mode_s = "block device";
-	else
-		mode_s = "other";
-
-	lua_pushstring(L, mode_s);
-}
-
-static void
-push_st_permissions(lua_State *L, struct stat *sb)
-{
-	char buf[20];
-
-	/*
-	 * XXX
-	 * Could actually format as "-rwxrwxrwx" -- do we care?
-	 */
-	snprintf(buf, sizeof(buf), "%o", sb->st_mode & ~S_IFMT);
-	lua_pushstring(L, buf);
-}
-
-#define PUSH_ENTRY(n)	{ #n, push_st_ ## n }
-struct stat_members {
-	const char *name;
-	void (*push)(lua_State *, struct stat *);
-} members[] = {
-	PUSH_ENTRY(mode),
-	PUSH_ENTRY(dev),
-	PUSH_ENTRY(ino),
-	PUSH_ENTRY(nlink),
-	PUSH_ENTRY(uid),
-	PUSH_ENTRY(gid),
-	PUSH_ENTRY(rdev),
-	PUSH_ENTRY(access),
-	PUSH_ENTRY(modification),
-	PUSH_ENTRY(change),
-	PUSH_ENTRY(size),
-	PUSH_ENTRY(permissions),
-};
-#undef PUSH_ENTRY
-
-static int
-lua_attributes(lua_State *L)
-{
-	struct stat sb;
-	const char *path, *member;
-	size_t i;
-	int rc;
-
-	path = luaL_checkstring(L, 1);
-	if (path == NULL) {
-		lua_pushnil(L);
-		lua_pushfstring(L, "cannot convert first argument to string");
-		lua_pushinteger(L, EINVAL);
-		return 3;
-	}
-
-	rc = stat(path, &sb);
-	if (rc != 0) {
-		lua_pushnil(L);
-		lua_pushfstring(L,
-		    "cannot obtain information from file '%s': %s", path,
-		    strerror(errno));
-		lua_pushinteger(L, errno);
-		return 3;
-	}
-
-	if (lua_isstring(L, 2)) {
-		member = lua_tostring(L, 2);
-		for (i = 0; i < nitems(members); i++) {
-			if (strcmp(members[i].name, member) != 0)
-				continue;
-
-			members[i].push(L, &sb);
-			return 1;
-		}
-		return luaL_error(L, "invalid attribute name '%s'", member);
-	}
-
-	/* Create or reuse existing table */
-	lua_settop(L, 2);
-	if (!lua_istable(L, 2))
-		lua_newtable(L);
-
-	/* Export all stat data to caller */
-	for (i = 0; i < nitems(members); i++) {
-		lua_pushstring(L, members[i].name);
-		members[i].push(L, &sb);
-		lua_rawset(L, -3);
-	}
-	return 1;
-}
-
-#define REG_SIMPLE(n)	{ #n, lua_ ## n }
-static const struct luaL_Reg fslib[] = {
-	REG_SIMPLE(attributes),
-	REG_SIMPLE(dir),
-	{ NULL, NULL },
-};
-#undef REG_SIMPLE
-
-int
-luaopen_lfs(lua_State *L)
-{
-	register_metatable(L);
-	luaL_newlib(L, fslib);
-	return 1;
-}
diff --git a/stand/liblua/lfs.h b/stand/liblua/lfs.h
deleted file mode 100644
index 59fa5d4c92c0..000000000000
--- a/stand/liblua/lfs.h
+++ /dev/null
@@ -1,33 +0,0 @@
-/*-
- * 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.
- *
- * $FreeBSD$
- */
-
-#pragma once
-
-#include <lua.h>
-
-int luaopen_lfs(lua_State *L);