interp.c revision 329183 
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: stable/11/stand/common/interp.c 329183 2018-02-12 20:51:28Z kevans $");
29
30/*
31 * Simple commandline interpreter, toplevel and misc.
32 *
33 * XXX may be obsoleted by BootFORTH or some other, better, interpreter.
34 */
35
36#include <stand.h>
37#include <string.h>
38#include "bootstrap.h"
39
40#define	MAXARGS	20			/* maximum number of arguments allowed */
41
42/*
43 * Interactive mode
44 */
45void
46interact(void)
47{
48	static char	input[256];			/* big enough? */
49
50	interp_init();
51
52	printf("\n");
53
54	/*
55	 * Before interacting, we might want to autoboot.
56	 */
57	autoboot_maybe();
58
59	/*
60	 * Not autobooting, go manual
61	 */
62	printf("\nType '?' for a list of commands, 'help' for more detailed help.\n");
63	if (getenv("prompt") == NULL)
64		setenv("prompt", "${interpret}", 1);
65	if (getenv("interpret") == NULL)
66		setenv("interpret", "OK", 1);
67
68	for (;;) {
69		input[0] = '\0';
70		interp_emit_prompt();
71		ngets(input, sizeof(input));
72		interp_run(input);
73	}
74}
75
76/*
77 * Read commands from a file, then execute them.
78 *
79 * We store the commands in memory and close the source file so that the media
80 * holding it can safely go away while we are executing.
81 *
82 * Commands may be prefixed with '@' (so they aren't displayed) or '-' (so
83 * that the script won't stop if they fail).
84 */
85COMMAND_SET(include, "include", "read commands from a file", command_include);
86
87static int
88command_include(int argc, char *argv[])
89{
90	int		i;
91	int		res;
92	char		**argvbuf;
93
94	/*
95	 * Since argv is static, we need to save it here.
96	 */
97	argvbuf = (char**) calloc((u_int)argc, sizeof(char*));
98	for (i = 0; i < argc; i++)
99		argvbuf[i] = strdup(argv[i]);
100
101	res=CMD_OK;
102	for (i = 1; (i < argc) && (res == CMD_OK); i++)
103		res = interp_include(argvbuf[i]);
104
105	for (i = 0; i < argc; i++)
106		free(argvbuf[i]);
107	free(argvbuf);
108
109	return(res);
110}
111
112/*
113 * Emit the current prompt; use the same syntax as the parser
114 * for embedding environment variables. Does not accept input.
115 */
116void
117interp_emit_prompt(void)
118{
119	char		*pr, *p, *cp, *ev;
120
121	if ((cp = getenv("prompt")) == NULL)
122		cp = ">";
123	pr = p = strdup(cp);
124
125	while (*p != 0) {
126		if ((*p == '$') && (*(p+1) == '{')) {
127			for (cp = p + 2; (*cp != 0) && (*cp != '}'); cp++)
128				;
129			*cp = 0;
130			ev = getenv(p + 2);
131
132			if (ev != NULL)
133				printf("%s", ev);
134			p = cp + 1;
135			continue;
136		}
137		putchar(*p++);
138	}
139	putchar(' ');
140	free(pr);
141}
142
143/*
144 * Perform a builtin command
145 */
146int
147interp_builtin_cmd(int argc, char *argv[])
148{
149	int			result;
150	struct bootblk_command	**cmdp;
151	bootblk_cmd_t		*cmd;
152
153	if (argc < 1)
154		return(CMD_OK);
155
156	/* set return defaults; a successful command will override these */
157	command_errmsg = command_errbuf;
158	strcpy(command_errbuf, "no error message");
159	cmd = NULL;
160	result = CMD_ERROR;
161
162	/* search the command set for the command */
163	SET_FOREACH(cmdp, Xcommand_set) {
164		if (((*cmdp)->c_name != NULL) && !strcmp(argv[0], (*cmdp)->c_name))
165			cmd = (*cmdp)->c_fn;
166	}
167	if (cmd != NULL) {
168		result = (cmd)(argc, argv);
169	} else {
170		command_errmsg = "unknown command";
171	}
172	return(result);
173}
174