xref: /freebsd/stand/common/interp_simple.c (revision d34048812292b714a0bf99967270d18fe3097c62)
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 INTERP_DEFINE("simp");
39 
40 void
41 interp_init(void)
42 {
43 
44 	setenv("script.lang", "simple", 1);
45 	/* Read our default configuration. */
46 	interp_include("/boot/loader.rc");
47 }
48 
49 int
50 interp_run(const char *input)
51 {
52 	int			argc;
53 	char			**argv;
54 
55 	if (parse(&argc, &argv, input)) {
56 		printf("parse error\n");
57 		return CMD_ERROR;
58 	}
59 
60 	if (interp_builtin_cmd(argc, argv)) {
61 		printf("%s: %s\n", argv[0], command_errmsg);
62 		free(argv);
63 		return CMD_ERROR;
64 	}
65 	free(argv);
66 	return CMD_OK;
67 }
68 
69 /*
70  * Header prepended to each line. The text immediately follows the header.
71  * We try to make this short in order to save memory -- the loader has
72  * limited memory available, and some of the forth files are very long.
73  */
74 struct includeline
75 {
76 	struct includeline	*next;
77 	int			flags;
78 	int			line;
79 #define SL_QUIET	(1<<0)
80 #define SL_IGNOREERR	(1<<1)
81 	char			text[0];
82 };
83 
84 int
85 interp_include(const char *filename)
86 {
87 	struct includeline	*script, *se, *sp;
88 	char			input[256];			/* big enough? */
89 	int			argc,res;
90 	char			**argv, *cp;
91 	int			fd, flags, line;
92 
93 	if (((fd = open(filename, O_RDONLY)) == -1)) {
94 		snprintf(command_errbuf, sizeof(command_errbuf),
95 		    "can't open '%s': %s", filename, strerror(errno));
96 		return(CMD_ERROR);
97 	}
98 
99 	/*
100 	 * Read the script into memory.
101 	 */
102 	script = se = NULL;
103 	line = 0;
104 
105 	while (fgetstr(input, sizeof(input), fd) >= 0) {
106 		line++;
107 		flags = 0;
108 		/* Discard comments */
109 		if (strncmp(input+strspn(input, " "), "\\ ", 2) == 0)
110 			continue;
111 		cp = input;
112 		/* Echo? */
113 		if (input[0] == '@') {
114 			cp++;
115 			flags |= SL_QUIET;
116 		}
117 		/* Error OK? */
118 		if (input[0] == '-') {
119 			cp++;
120 			flags |= SL_IGNOREERR;
121 		}
122 
123 		/* Allocate script line structure and copy line, flags */
124 		if (*cp == '\0')
125 			continue;	/* ignore empty line, save memory */
126 		sp = malloc(sizeof(struct includeline) + strlen(cp) + 1);
127 		/* On malloc failure (it happens!), free as much as possible and exit */
128 		if (sp == NULL) {
129 			while (script != NULL) {
130 				se = script;
131 				script = script->next;
132 				free(se);
133 			}
134 			snprintf(command_errbuf, sizeof(command_errbuf),
135 			    "file '%s' line %d: memory allocation failure - aborting",
136 			    filename, line);
137 			close(fd);
138 			return (CMD_ERROR);
139 		}
140 		strcpy(sp->text, cp);
141 		sp->flags = flags;
142 		sp->line = line;
143 		sp->next = NULL;
144 
145 		if (script == NULL) {
146 			script = sp;
147 		} else {
148 			se->next = sp;
149 		}
150 		se = sp;
151 	}
152 	close(fd);
153 
154 	/*
155 	 * Execute the script
156 	 */
157 	argv = NULL;
158 	res = CMD_OK;
159 	for (sp = script; sp != NULL; sp = sp->next) {
160 
161 		/* print if not being quiet */
162 		if (!(sp->flags & SL_QUIET)) {
163 			interp_emit_prompt();
164 			printf("%s\n", sp->text);
165 		}
166 
167 		/* Parse the command */
168 		if (!parse(&argc, &argv, sp->text)) {
169 			if ((argc > 0) && (interp_builtin_cmd(argc, argv) != 0)) {
170 				/* normal command */
171 				printf("%s: %s\n", argv[0], command_errmsg);
172 				if (!(sp->flags & SL_IGNOREERR)) {
173 					res=CMD_ERROR;
174 					break;
175 				}
176 			}
177 			free(argv);
178 			argv = NULL;
179 		} else {
180 			printf("%s line %d: parse error\n", filename, sp->line);
181 			res=CMD_ERROR;
182 			break;
183 		}
184 	}
185 	if (argv != NULL)
186 		free(argv);
187 
188 	while (script != NULL) {
189 		se = script;
190 		script = script->next;
191 		free(se);
192 	}
193 	return(res);
194 }
195