xref: /freebsd/stand/common/interp_lua.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
1 /*-
2  * Copyright (c) 2011 Wojciech A. Koszek <wkoszek@FreeBSD.org>
3  * Copyright (c) 2014 Pedro Souza <pedrosouza@freebsd.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided 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 AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY 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, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <stand.h>
32 #include "bootstrap.h"
33 
34 #define lua_c
35 
36 #include "lstd.h"
37 
38 #include <lua.h>
39 #include <ldebug.h>
40 #include <lauxlib.h>
41 #include <lualib.h>
42 
43 #include <lerrno.h>
44 #include <lfs.h>
45 #include <lutils.h>
46 
47 struct interp_lua_softc {
48 	lua_State	*luap;
49 };
50 
51 static struct interp_lua_softc lua_softc;
52 
53 #ifdef LUA_DEBUG
54 #define	LDBG(...)	do {			\
55 	printf("%s(%d): ", __func__, __LINE__);	\
56 	printf(__VA_ARGS__);			\
57 	printf("\n");				\
58 } while (0)
59 #else
60 #define	LDBG(...)
61 #endif
62 
63 
64 static void *
65 interp_lua_realloc(void *ud __unused, void *ptr, size_t osize __unused, size_t nsize)
66 {
67 
68 	if (nsize == 0) {
69 		free(ptr);
70 		return NULL;
71 	}
72 	return realloc(ptr, nsize);
73 }
74 
75 /*
76  * The libraries commented out below either lack the proper
77  * support from libsa, or they are unlikely to be useful
78  * in the bootloader, so have been commented out.
79  */
80 static const luaL_Reg loadedlibs[] = {
81   {"_G", luaopen_base},
82   {LUA_LOADLIBNAME, luaopen_package},
83 //  {LUA_COLIBNAME, luaopen_coroutine},
84 //  {LUA_TABLIBNAME, luaopen_table},
85   {LUA_STRLIBNAME, luaopen_string},
86 //  {LUA_IOLIBNAME, luaopen_io},
87 //  {LUA_OSLIBNAME, luaopen_os},
88 //  {LUA_MATHLIBNAME, luaopen_math},
89 //  {LUA_UTF8LIBNAME, luaopen_utf8},
90 //  {LUA_DBLIBNAME, luaopen_debug},
91   {"errno", luaopen_errno},
92   {"io", luaopen_io},
93   {"lfs", luaopen_lfs},
94   {"loader", luaopen_loader},
95   {NULL, NULL}
96 };
97 
98 void
99 interp_init(void)
100 {
101 	lua_State *luap;
102 	struct interp_lua_softc	*softc = &lua_softc;
103 	const char *filename;
104 	const luaL_Reg *lib;
105 
106 	setenv("script.lang", "lua", 1);
107 	LDBG("creating context");
108 
109 	luap = lua_newstate(interp_lua_realloc, NULL);
110 	if (luap == NULL) {
111 		printf("problem initializing the Lua interpreter\n");
112 		abort();
113 	}
114 	softc->luap = luap;
115 
116 	/* "require" functions from 'loadedlibs' and set results to global table */
117 	for (lib = loadedlibs; lib->func; lib++) {
118 		luaL_requiref(luap, lib->name, lib->func, 1);
119 		lua_pop(luap, 1);  /* remove lib */
120 	}
121 
122 	filename = "/boot/lua/loader.lua";
123 	if (interp_include(filename) != 0) {
124                 const char *errstr = lua_tostring(luap, -1);
125                 errstr = errstr == NULL ? "unknown" : errstr;
126                 printf("Startup error in %s:\nLUA ERROR: %s.\n", filename, errstr);
127                 lua_pop(luap, 1);
128 	}
129 }
130 
131 int
132 interp_run(const char *line)
133 {
134 	int	argc, nargc;
135 	char	**argv;
136 	lua_State *luap;
137 	struct interp_lua_softc	*softc = &lua_softc;
138 	int status;
139 
140 	luap = softc->luap;
141 	LDBG("executing line...");
142 	if ((status = luaL_dostring(luap, line)) != 0) {
143                 lua_pop(luap, 1);
144 		/*
145 		 * The line wasn't executable as lua; run it through parse to
146 		 * to get consistent parsing of command line arguments, then
147 		 * run it through cli_execute. If that fails, then we'll try it
148 		 * as a builtin.
149 		 */
150 		if (parse(&argc, &argv, line) == 0) {
151 			lua_getglobal(luap, "cli_execute");
152 			for (nargc = 0; nargc < argc; ++nargc) {
153 				lua_pushstring(luap, argv[nargc]);
154 			}
155 			status = lua_pcall(luap, argc, 1, 0);
156 			lua_pop(luap, 1);
157 			if (status != 0) {
158 				/*
159 				 * Lua cli_execute will pass the function back
160 				 * through loader.command, which is a proxy to
161 				 * interp_builtin_cmd. If we failed to interpret
162 				 * the command, though, then there's a chance
163 				 * that didn't happen. Call interp_builtin_cmd
164 				 * directly if our lua_pcall was not successful.
165 				 */
166 				status = interp_builtin_cmd(argc, argv);
167 			}
168 			if (status != 0) {
169 				printf("Command failed\n");
170 				status = CMD_ERROR;
171 			}
172 			free(argv);
173 		} else {
174 			printf("Failed to parse \'%s\'\n", line);
175 			status = CMD_ERROR;
176 		}
177 	}
178 
179 	return (status == 0 ? CMD_OK : CMD_ERROR);
180 }
181 
182 int
183 interp_include(const char *filename)
184 {
185 	struct interp_lua_softc	*softc = &lua_softc;
186 
187 	LDBG("loading file %s", filename);
188 
189 	return (luaL_dofile(softc->luap, filename));
190 }
191