interp.c revision 38716 
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 *	$Id: interp.c,v 1.1.1.1 1998/08/21 03:17:41 msmith Exp $
27 */
28/*
29 * Simple commandline interpreter, toplevel and misc.
30 *
31 * XXX may be obsoleted by BootFORTH
32 */
33
34#include <stand.h>
35#include <string.h>
36#include "bootstrap.h"
37
38#define	MAXARGS	20			/* maximum number of arguments allowed */
39
40extern int	parse(int *argc, char ***argv, char *str);	/* interp_parse.c */
41
42static void	prompt(void);
43
44/*
45 * Perform the command
46 */
47static int
48perform(int argc, char *argv[])
49{
50    int				i, result;
51    struct bootblk_command	**cmdp;
52    bootblk_cmd_t		*cmd;
53
54    if (argc < 1)
55	return(CMD_OK);
56
57    /* set return defaults; a successful command will override these */
58    command_errmsg = command_errbuf;
59    strcpy(command_errbuf, "no error message");
60    cmd = NULL;
61    result = CMD_ERROR;
62
63    cmdp = (struct bootblk_command **)Xcommand_set.ls_items;
64    for (i = 0; i < Xcommand_set.ls_length; i++) {
65	if ((cmdp[i]->c_name != NULL) && !strcmp(argv[0], cmdp[i]->c_name))
66	    cmd = cmdp[i]->c_fn;
67    }
68    if (cmd != NULL) {
69	result = (cmd)(argc, argv);
70    } else {
71	command_errmsg = "unknown command";
72    }
73    return(result);
74}
75
76/*
77 * Interactive mode
78 */
79void
80interact(void)
81{
82    char	input[256];			/* big enough? */
83    int		argc;
84    char	**argv;
85
86    for (;;) {
87	input[0] = '\0';
88	prompt();
89	ngets(input, sizeof(input));
90	if (!parse(&argc, &argv, input)) {
91	    if (perform(argc, argv))
92		printf("%s: %s\n", argv[0], command_errmsg);
93	    free(argv);
94	} else {
95	    printf("parse error\n");
96	}
97    }
98}
99
100/*
101 * Read command from a file
102 */
103COMMAND_SET(source, "source", "read commands from a file", command_source);
104
105static int
106command_source(int argc, char *argv[])
107{
108    int		i;
109
110    for (i = 1; i < argc; i++)
111	source(argv[i]);
112    return(CMD_OK);
113}
114
115void
116source(char *filename)
117{
118    char	input[256];			/* big enough? */
119    int		argc;
120    char	**argv, *cp;
121    int		fd;
122
123    if (((fd = open(filename, O_RDONLY)) == -1)) {
124	printf("can't open '%s': %s\n", filename, strerror(errno));
125    } else {
126	while (fgetstr(input, sizeof(input), fd) > 0) {
127
128	    /* Discard comments */
129	    if (input[0] == '#')
130		continue;
131	    cp = input;
132	    /* Echo? */
133	    if (input[0] == '@') {
134		cp++;
135	    } else {
136		prompt();
137		printf("%s\n", input);
138	    }
139
140	    if (!parse(&argc, &argv, cp)) {
141		if ((argc > 0) &&
142		    (perform(argc, argv) != 0))
143		    printf("%s: %s\n", argv[0], command_errmsg);
144		free(argv);
145	    }
146	}
147	close(fd);
148    }
149}
150
151/*
152 * Emit the current prompt; support primitive embedding of
153 * environment variables.
154 * We're a little rude here, modifying the return from getenv().
155 */
156static void
157prompt(void)
158{
159    char	*p, *cp, *ev, c;
160
161    if ((p = getenv("prompt")) == NULL)
162	p = ">";
163
164    while (*p != 0) {
165	if (*p == '$') {
166	    for (cp = p + 1; (*cp != 0) && isalpha(*cp); cp++)
167		;
168	    c = *cp;
169	    *cp = 0;
170	    ev = getenv(p + 1);
171	    *cp = c;
172
173	    if (ev != NULL) {
174		printf(ev);
175		p = cp;
176		continue;
177	    }
178	}
179	putchar(*p++);
180    }
181    putchar(' ');
182}
183