xref: /freebsd/libexec/flua/modules/lposix.c (revision 657729a89dd578d8cfc70d6616f5c65a48a8b33a)
1 /*-
2  * Copyright (c) 2019 Kyle Evans <kevans@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  *
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/stat.h>
31 
32 #include <errno.h>
33 #include <grp.h>
34 #include <pwd.h>
35 #include <string.h>
36 #include <unistd.h>
37 
38 #include <lua.h>
39 #include "lauxlib.h"
40 #include "lposix.h"
41 
42 /*
43  * Minimal implementation of luaposix needed for internal FreeBSD bits.
44  */
45 
46 static int
47 lua_chmod(lua_State *L)
48 {
49 	int n;
50 	const char *path;
51 	mode_t mode;
52 
53 	n = lua_gettop(L);
54 	luaL_argcheck(L, n == 2, n > 2 ? 3 : n,
55 	    "chmod takes exactly two arguments");
56 	path = luaL_checkstring(L, 1);
57 	mode = (mode_t)luaL_checkinteger(L, 2);
58 	if (chmod(path, mode) == -1) {
59 		lua_pushnil(L);
60 		lua_pushstring(L, strerror(errno));
61 		lua_pushinteger(L, errno);
62 		return 3;
63 	}
64 	lua_pushinteger(L, 0);
65 	return 1;
66 }
67 
68 static int
69 lua_chown(lua_State *L)
70 {
71 	int n;
72 	const char *path;
73 	uid_t owner = (uid_t) -1;
74 	gid_t group = (gid_t) -1;
75 
76 	n = lua_gettop(L);
77 	luaL_argcheck(L, n > 1, n,
78 	   "chown takes at least two arguments");
79 	path = luaL_checkstring(L, 1);
80 	if (lua_isinteger(L, 2))
81 		owner = (uid_t) lua_tointeger(L, 2);
82 	else if (lua_isstring(L, 2)) {
83 		struct passwd *p = getpwnam(lua_tostring(L, 2));
84 		if (p != NULL)
85 			owner = p->pw_uid;
86 		else
87 			return (luaL_argerror(L, 2,
88 			    lua_pushfstring(L, "unknown user %s",
89 			    lua_tostring(L, 2))));
90 	} else if (!lua_isnoneornil(L, 2)) {
91 		const char *type = luaL_typename(L, 2);
92 		return (luaL_argerror(L, 2,
93 		    lua_pushfstring(L, "integer or string expected, got %s",
94 		    type)));
95 	}
96 
97 	if (lua_isinteger(L, 3))
98 		group = (gid_t) lua_tointeger(L, 3);
99 	else if (lua_isstring(L, 3)) {
100 		struct group *g = getgrnam(lua_tostring(L, 3));
101 		if (g != NULL)
102 			group = g->gr_gid;
103 		else
104 			return (luaL_argerror(L, 3,
105 			    lua_pushfstring(L, "unknown group %s",
106 			    lua_tostring(L, 3))));
107 	} else if (!lua_isnoneornil(L, 3)) {
108 		const char *type = luaL_typename(L, 3);
109 		return (luaL_argerror(L, 3,
110 		    lua_pushfstring(L, "integer or string expected, got %s",
111 		    type)));
112 	}
113 
114 	if (chown(path, owner, group) == -1) {
115 		lua_pushnil(L);
116 		lua_pushstring(L, strerror(errno));
117 		lua_pushinteger(L, errno);
118 		return (3);
119 	}
120 	lua_pushinteger(L, 0);
121 	return (1);
122 }
123 
124 static int
125 lua_getpid(lua_State *L)
126 {
127 	int n;
128 
129 	n = lua_gettop(L);
130 	luaL_argcheck(L, n == 0, 1, "too many arguments");
131 	lua_pushinteger(L, getpid());
132 	return 1;
133 }
134 
135 #define REG_SIMPLE(n)	{ #n, lua_ ## n }
136 static const struct luaL_Reg sys_statlib[] = {
137 	REG_SIMPLE(chmod),
138 	{ NULL, NULL },
139 };
140 
141 static const struct luaL_Reg unistdlib[] = {
142 	REG_SIMPLE(getpid),
143 	REG_SIMPLE(chown),
144 	{ NULL, NULL },
145 };
146 #undef REG_SIMPLE
147 
148 int
149 luaopen_posix_sys_stat(lua_State *L)
150 {
151 	luaL_newlib(L, sys_statlib);
152 	return 1;
153 }
154 
155 int
156 luaopen_posix_unistd(lua_State *L)
157 {
158 	luaL_newlib(L, unistdlib);
159 	return 1;
160 }
161