1 /* 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright 2023 Baptiste Daroussin <bapt@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted providing that the following conditions~ 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 23 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 24 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25 * POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <sys/wait.h> 29 30 #include <errno.h> 31 #include <fcntl.h> 32 #include <spawn.h> 33 #include <string.h> 34 #include <stdio.h> 35 #include <unistd.h> 36 37 #include <lua.h> 38 #include "lauxlib.h" 39 #include "lfbsd.h" 40 41 extern char **environ; 42 43 static const char** 44 luaL_checkarraystrings(lua_State *L, int arg) 45 { 46 const char **ret; 47 lua_Integer n, i; 48 int t; 49 int abs_arg = lua_absindex(L, arg); 50 luaL_checktype(L, abs_arg, LUA_TTABLE); 51 n = lua_rawlen(L, abs_arg); 52 ret = lua_newuserdata(L, (n+1)*sizeof(char*)); 53 for (i=0; i<n; i++) { 54 t = lua_rawgeti(L, abs_arg, i+1); 55 if (t == LUA_TNIL) 56 break; 57 luaL_argcheck(L, t == LUA_TSTRING, arg, "expected array of strings"); 58 ret[i] = lua_tostring(L, -1); 59 lua_pop(L, 1); 60 } 61 ret[i] = NULL; 62 return ret; 63 } 64 65 static int 66 lua_exec(lua_State *L) 67 { 68 int r, pstat; 69 posix_spawn_file_actions_t action; 70 int stdin_pipe[2] = {-1, -1}; 71 pid_t pid; 72 const char **argv; 73 int n = lua_gettop(L); 74 luaL_argcheck(L, n == 1, n > 1 ? 2 : n, 75 "fbsd.exec takes exactly one argument"); 76 77 if (pipe(stdin_pipe) < 0) { 78 lua_pushnil(L); 79 lua_pushstring(L, strerror(errno)); 80 lua_pushinteger(L, errno); 81 return (3); 82 } 83 84 posix_spawn_file_actions_init(&action); 85 posix_spawn_file_actions_adddup2(&action, stdin_pipe[0], STDIN_FILENO); 86 posix_spawn_file_actions_addclose(&action, stdin_pipe[1]); 87 88 argv = luaL_checkarraystrings(L, 1); 89 if (0 != (r = posix_spawnp(&pid, argv[0], &action, NULL, 90 (char*const*)argv, environ))) { 91 lua_pushnil(L); 92 lua_pushstring(L, strerror(r)); 93 lua_pushinteger(L, r); 94 return (3); 95 } 96 while (waitpid(pid, &pstat, 0) == -1) { 97 if (errno != EINTR) { 98 lua_pushnil(L); 99 lua_pushstring(L, strerror(r)); 100 lua_pushinteger(L, r); 101 return (3); 102 } 103 } 104 105 if (WEXITSTATUS(pstat) != 0) { 106 lua_pushnil(L); 107 lua_pushstring(L, "Abnormal termination"); 108 lua_pushinteger(L, r); 109 return (3); 110 } 111 112 posix_spawn_file_actions_destroy(&action); 113 114 if (stdin_pipe[0] != -1) 115 close(stdin_pipe[0]); 116 if (stdin_pipe[1] != -1) 117 close(stdin_pipe[1]); 118 lua_pushinteger(L, pid); 119 return 1; 120 } 121 122 #define REG_SIMPLE(n) { #n, lua_ ## n } 123 static const struct luaL_Reg fbsd_lib[] = { 124 REG_SIMPLE(exec), 125 { NULL, NULL }, 126 }; 127 #undef REG_SIMPLE 128 129 int 130 luaopen_fbsd(lua_State *L) 131 { 132 luaL_newlib(L, fbsd_lib); 133 return (1); 134 } 135