xref: /csrg-svn/usr.sbin/lpr/lpc/lpc.c (revision 22428)
1 /*
2  * Copyright (c) 1983 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  */
6 
7 #ifndef lint
8 char copyright[] =
9 "@(#) Copyright (c) 1983 Regents of the University of California.\n\
10  All rights reserved.\n";
11 #endif not lint
12 
13 #ifndef lint
14 static char sccsid[] = "@(#)lpc.c	5.1 (Berkeley) 06/06/85";
15 #endif not lint
16 
17 /*
18  * lpc -- line printer control program
19  */
20 #include <stdio.h>
21 #include <signal.h>
22 #include <ctype.h>
23 #include <setjmp.h>
24 
25 #include "lpc.h"
26 
27 int	fromatty;
28 
29 char	cmdline[200];
30 int	margc;
31 char	*margv[20];
32 int	top;
33 int	intr();
34 struct	cmd *getcmd();
35 
36 jmp_buf	toplevel;
37 
38 main(argc, argv)
39 	char *argv[];
40 {
41 	register struct cmd *c;
42 	extern char *name;
43 
44 	name = argv[0];
45 
46 	if (--argc > 0) {
47 		c = getcmd(*++argv);
48 		if (c == (struct cmd *)-1) {
49 			printf("?Ambiguous command\n");
50 			exit(1);
51 		}
52 		if (c == 0) {
53 			printf("?Invalid command\n");
54 			exit(1);
55 		}
56 		if (c->c_priv && getuid()) {
57 			printf("?Privileged command\n");
58 			exit(1);
59 		}
60 		(*c->c_handler)(argc, argv);
61 		exit(0);
62 	}
63 	fromatty = isatty(fileno(stdin));
64 	top = setjmp(toplevel) == 0;
65 	if (top)
66 		signal(SIGINT, intr);
67 	for (;;) {
68 		cmdscanner(top);
69 		top = 1;
70 	}
71 }
72 
73 intr()
74 {
75 	if (!fromatty)
76 		exit(0);
77 	longjmp(toplevel, 1);
78 }
79 
80 /*
81  * Command parser.
82  */
83 cmdscanner(top)
84 	int top;
85 {
86 	register struct cmd *c;
87 	extern struct cmd cmdtab[];
88 	extern int help();
89 
90 	if (!top)
91 		putchar('\n');
92 	for (;;) {
93 		if (fromatty) {
94 			printf("lpc> ");
95 			fflush(stdout);
96 		}
97 		if (gets(cmdline) == 0)
98 			quit();
99 		if (cmdline[0] == 0)
100 			break;
101 		makeargv();
102 		c = getcmd(margv[0]);
103 		if (c == (struct cmd *)-1) {
104 			printf("?Ambiguous command\n");
105 			continue;
106 		}
107 		if (c == 0) {
108 			printf("?Invalid command\n");
109 			continue;
110 		}
111 		if (c->c_priv && getuid()) {
112 			printf("?Privileged command\n");
113 			continue;
114 		}
115 		(*c->c_handler)(margc, margv);
116 	}
117 	longjmp(toplevel, 0);
118 }
119 
120 struct cmd *
121 getcmd(name)
122 	register char *name;
123 {
124 	register char *p, *q;
125 	register struct cmd *c, *found;
126 	register int nmatches, longest;
127 
128 	longest = 0;
129 	nmatches = 0;
130 	found = 0;
131 	for (c = cmdtab; p = c->c_name; c++) {
132 		for (q = name; *q == *p++; q++)
133 			if (*q == 0)		/* exact match? */
134 				return(c);
135 		if (!*q) {			/* the name was a prefix */
136 			if (q - name > longest) {
137 				longest = q - name;
138 				nmatches = 1;
139 				found = c;
140 			} else if (q - name == longest)
141 				nmatches++;
142 		}
143 	}
144 	if (nmatches > 1)
145 		return((struct cmd *)-1);
146 	return(found);
147 }
148 
149 /*
150  * Slice a string up into argc/argv.
151  */
152 makeargv()
153 {
154 	register char *cp;
155 	register char **argp = margv;
156 
157 	margc = 0;
158 	for (cp = cmdline; *cp;) {
159 		while (isspace(*cp))
160 			cp++;
161 		if (*cp == '\0')
162 			break;
163 		*argp++ = cp;
164 		margc += 1;
165 		while (*cp != '\0' && !isspace(*cp))
166 			cp++;
167 		if (*cp == '\0')
168 			break;
169 		*cp++ = '\0';
170 	}
171 	*argp++ = 0;
172 }
173 
174 #define HELPINDENT (sizeof ("directory"))
175 
176 /*
177  * Help command.
178  */
179 help(argc, argv)
180 	int argc;
181 	char *argv[];
182 {
183 	register struct cmd *c;
184 
185 	if (argc == 1) {
186 		register int i, j, w;
187 		int columns, width = 0, lines;
188 		extern int NCMDS;
189 
190 		printf("Commands may be abbreviated.  Commands are:\n\n");
191 		for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
192 			int len = strlen(c->c_name);
193 
194 			if (len > width)
195 				width = len;
196 		}
197 		width = (width + 8) &~ 7;
198 		columns = 80 / width;
199 		if (columns == 0)
200 			columns = 1;
201 		lines = (NCMDS + columns - 1) / columns;
202 		for (i = 0; i < lines; i++) {
203 			for (j = 0; j < columns; j++) {
204 				c = cmdtab + j * lines + i;
205 				printf("%s", c->c_name);
206 				if (c + lines >= &cmdtab[NCMDS]) {
207 					printf("\n");
208 					break;
209 				}
210 				w = strlen(c->c_name);
211 				while (w < width) {
212 					w = (w + 8) &~ 7;
213 					putchar('\t');
214 				}
215 			}
216 		}
217 		return;
218 	}
219 	while (--argc > 0) {
220 		register char *arg;
221 		arg = *++argv;
222 		c = getcmd(arg);
223 		if (c == (struct cmd *)-1)
224 			printf("?Ambiguous help command %s\n", arg);
225 		else if (c == (struct cmd *)0)
226 			printf("?Invalid help command %s\n", arg);
227 		else
228 			printf("%-*s\t%s\n", HELPINDENT,
229 				c->c_name, c->c_help);
230 	}
231 }
232