From 31587f7c869c75d1a37aa269739618232490cef2 Mon Sep 17 00:00:00 2001
From: emaste <emaste@FreeBSD.org>
Date: Fri, 13 Mar 2020 15:40:35 +0000
Subject: [PATCH] flua: implement chmod

Lua does not provide a native way to change the permission of a file.

Submitted by:	Yang Wang <2333@outlook.jp>
Reviewed by:	kevans
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D24036
---
 libexec/flua/linit_flua.c     |  1 +
 libexec/flua/modules/lposix.c | 38 +++++++++++++++++++++++++++++++++++
 libexec/flua/modules/lposix.h |  1 +
 3 files changed, 40 insertions(+)

diff --git a/libexec/flua/linit_flua.c b/libexec/flua/linit_flua.c
index 4b4069e9ad62..99818c3b4db7 100644
--- a/libexec/flua/linit_flua.c
+++ b/libexec/flua/linit_flua.c
@@ -57,6 +57,7 @@ static const luaL_Reg loadedlibs[] = {
 #endif
   /* FreeBSD Extensions */
   {"lfs", luaopen_lfs},
+  {"posix.sys.stat", luaopen_posix_sys_stat},
   {"posix.unistd", luaopen_posix_unistd},
   {NULL, NULL}
 };
diff --git a/libexec/flua/modules/lposix.c b/libexec/flua/modules/lposix.c
index 208802456fed..adf3a7bb9a1f 100644
--- a/libexec/flua/modules/lposix.c
+++ b/libexec/flua/modules/lposix.c
@@ -27,6 +27,10 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <string.h>
 #include <unistd.h>
 
 #include <lua.h>
@@ -37,6 +41,28 @@ __FBSDID("$FreeBSD$");
  * Minimal implementation of luaposix needed for internal FreeBSD bits.
  */
 
+static int
+lua_chmod(lua_State *L)
+{
+	int n;
+	const char *path;
+	mode_t mode;
+
+	n = lua_gettop(L);
+	luaL_argcheck(L, n == 2, n > 2 ? 3 : n,
+	    "chmod takes exactly two arguments");
+	path = luaL_checkstring(L, 1);
+	mode = (mode_t)luaL_checkinteger(L, 2);
+	if (chmod(path, mode) == -1) {
+		lua_pushnil(L);
+		lua_pushstring(L, strerror(errno));
+		lua_pushinteger(L, errno);
+		return 3;
+	}
+	lua_pushinteger(L, 0);
+	return 1;
+}
+
 static int
 lua_getpid(lua_State *L)
 {
@@ -49,12 +75,24 @@ lua_getpid(lua_State *L)
 }
 
 #define REG_SIMPLE(n)	{ #n, lua_ ## n }
+static const struct luaL_Reg sys_statlib[] = {
+	REG_SIMPLE(chmod),
+	{ NULL, NULL },
+};
+
 static const struct luaL_Reg unistdlib[] = {
 	REG_SIMPLE(getpid),
 	{ NULL, NULL },
 };
 #undef REG_SIMPLE
 
+int
+luaopen_posix_sys_stat(lua_State *L)
+{
+	luaL_newlib(L, sys_statlib);
+	return 1;
+}
+
 int
 luaopen_posix_unistd(lua_State *L)
 {
diff --git a/libexec/flua/modules/lposix.h b/libexec/flua/modules/lposix.h
index 4c771d79769f..d2d9ec0cd677 100644
--- a/libexec/flua/modules/lposix.h
+++ b/libexec/flua/modules/lposix.h
@@ -8,4 +8,5 @@
 
 #include <lua.h>
 
+int luaopen_posix_sys_stat(lua_State *L);
 int luaopen_posix_unistd(lua_State *L);