xref: /freebsd/stand/common/interp_simple.c (revision 63a938566d524836885917d95bd491aa4400b181)
1 /*-
2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 /*
31  * Simple commandline interpreter, toplevel and misc.
32  */
33 
34 #include <stand.h>
35 #include <string.h>
36 #include "bootstrap.h"
37 
38 void
39 interp_init(void)
40 {
41 
42 	setenv("script.lang", "simple", 1);
43 	/* Read our default configuration. */
44 	interp_include("/boot/loader.rc");
45 }
46 
47 int
48 interp_run(const char *input)
49 {
50 	int			argc;
51 	char			**argv;
52 
53 	if (parse(&argc, &argv, input)) {
54 		printf("parse error\n");
55 		return CMD_ERROR;
56 	}
57 
58 	if (interp_builtin_cmd(argc, argv)) {
59 		printf("%s: %s\n", argv[0], command_errmsg);
60 		free(argv);
61 		return CMD_ERROR;
62 	}
63 	free(argv);
64 	return CMD_OK;
65 }
66 
67 /*
68  * Header prepended to each line. The text immediately follows the header.
69  * We try to make this short in order to save memory -- the loader has
70  * limited memory available, and some of the forth files are very long.
71  */
72 struct includeline
73 {
74 	struct includeline	*next;
75 	int			flags;
76 	int			line;
77 #define SL_QUIET	(1<<0)
78 #define SL_IGNOREERR	(1<<1)
79 	char			text[0];
80 };
81 
82 int
83 interp_include(const char *filename)
84 {
85 	struct includeline	*script, *se, *sp;
86 	char			input[256];			/* big enough? */
87 	int			argc,res;
88 	char			**argv, *cp;
89 	int			fd, flags, line;
90 
91 	if (((fd = open(filename, O_RDONLY)) == -1)) {
92 		snprintf(command_errbuf, sizeof(command_errbuf),
93 		    "can't open '%s': %s", filename, strerror(errno));
94 		return(CMD_ERROR);
95 	}
96 
97 	/*
98 	 * Read the script into memory.
99 	 */
100 	script = se = NULL;
101 	line = 0;
102 
103 	while (fgetstr(input, sizeof(input), fd) >= 0) {
104 		line++;
105 		flags = 0;
106 		/* Discard comments */
107 		if (strncmp(input+strspn(input, " "), "\\ ", 2) == 0)
108 			continue;
109 		cp = input;
110 		/* Echo? */
111 		if (input[0] == '@') {
112 			cp++;
113 			flags |= SL_QUIET;
114 		}
115 		/* Error OK? */
116 		if (input[0] == '-') {
117 			cp++;
118 			flags |= SL_IGNOREERR;
119 		}
120 
121 		/* Allocate script line structure and copy line, flags */
122 		if (*cp == '\0')
123 			continue;	/* ignore empty line, save memory */
124 		sp = malloc(sizeof(struct includeline) + strlen(cp) + 1);
125 		/* On malloc failure (it happens!), free as much as possible and exit */
126 		if (sp == NULL) {
127 			while (script != NULL) {
128 				se = script;
129 				script = script->next;
130 				free(se);
131 			}
132 			snprintf(command_errbuf, sizeof(command_errbuf),
133 			    "file '%s' line %d: memory allocation failure - aborting",
134 			    filename, line);
135 			close(fd);
136 			return (CMD_ERROR);
137 		}
138 		strcpy(sp->text, cp);
139 		sp->flags = flags;
140 		sp->line = line;
141 		sp->next = NULL;
142 
143 		if (script == NULL) {
144 			script = sp;
145 		} else {
146 			se->next = sp;
147 		}
148 		se = sp;
149 	}
150 	close(fd);
151 
152 	/*
153 	 * Execute the script
154 	 */
155 	argv = NULL;
156 	res = CMD_OK;
157 	for (sp = script; sp != NULL; sp = sp->next) {
158 
159 		/* print if not being quiet */
160 		if (!(sp->flags & SL_QUIET)) {
161 			interp_emit_prompt();
162 			printf("%s\n", sp->text);
163 		}
164 
165 		/* Parse the command */
166 		if (!parse(&argc, &argv, sp->text)) {
167 			if ((argc > 0) && (interp_builtin_cmd(argc, argv) != 0)) {
168 				/* normal command */
169 				printf("%s: %s\n", argv[0], command_errmsg);
170 				if (!(sp->flags & SL_IGNOREERR)) {
171 					res=CMD_ERROR;
172 					break;
173 				}
174 			}
175 			free(argv);
176 			argv = NULL;
177 		} else {
178 			printf("%s line %d: parse error\n", filename, sp->line);
179 			res=CMD_ERROR;
180 			break;
181 		}
182 	}
183 	if (argv != NULL)
184 		free(argv);
185 
186 	while (script != NULL) {
187 		se = script;
188 		script = script->next;
189 		free(se);
190 	}
191 	return(res);
192 }
193