Generally use NULL instead of explicitly casting 0 to some pointer type.
[dragonfly.git] / usr.sbin / timed / timedc / timedc.c
1 /*-
2  * Copyright (c) 1985, 1993
3  *      The Regents of the University of California.  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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *      This product includes software developed by the University of
16  *      California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#) Copyright (c) 1985, 1993 The Regents of the University of California.  All rights reserved.
34  * @(#)timedc.c 8.1 (Berkeley) 6/6/93
35  * $FreeBSD: src/usr.sbin/timed/timedc/timedc.c,v 1.5 2003/10/11 07:35:35 tjr Exp $
36  * $DragonFly: src/usr.sbin/timed/timedc/timedc.c,v 1.8 2004/05/11 19:22:25 cpressey Exp $
37  */
38
39 #include "timedc.h"
40 #include <ctype.h>
41 #include <err.h>
42 #include <setjmp.h>
43 #include <signal.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <syslog.h>
47 #include <unistd.h>
48
49 int trace = 0;
50 FILE *fd = 0;
51 int     margc;
52 int     fromatty;
53 #define MAX_MARGV       20
54 char    *margv[MAX_MARGV];
55 char    cmdline[200];
56 jmp_buf toplevel;
57 static struct cmd *getcmd(char *);
58
59 int
60 main(int argc, char **argv)
61 {
62         struct cmd *c;
63
64         openlog("timedc", LOG_ODELAY, LOG_AUTH);
65
66         /*
67          * security dictates!
68          */
69         if (priv_resources() < 0)
70                 errx(1, "could not get privileged resources");
71         setuid(getuid());
72
73         if (--argc > 0) {
74                 c = getcmd(*++argv);
75                 if (c == (struct cmd *)-1) {
76                         printf("?Ambiguous command\n");
77                         exit(1);
78                 }
79                 if (c == 0) {
80                         printf("?Invalid command\n");
81                         exit(1);
82                 }
83                 if (c->c_priv && getuid()) {
84                         printf("?Privileged command\n");
85                         exit(1);
86                 }
87                 (*c->c_handler)(argc, argv);
88                 exit(0);
89         }
90
91         fromatty = isatty(fileno(stdin));
92         if (setjmp(toplevel))
93                 putchar('\n');
94         signal(SIGINT, intr);
95         for (;;) {
96                 if (fromatty) {
97                         printf("timedc> ");
98                         fflush(stdout);
99                 }
100                 if (fgets(cmdline, sizeof(cmdline), stdin) == 0)
101                         quit();
102                 if (cmdline[0] == 0)
103                         break;
104                 makeargv();
105                 if (margv[0] == 0)
106                         continue;
107                 c = getcmd(margv[0]);
108                 if (c == (struct cmd *)-1) {
109                         printf("?Ambiguous command\n");
110                         continue;
111                 }
112                 if (c == 0) {
113                         printf("?Invalid command\n");
114                         continue;
115                 }
116                 if (c->c_priv && getuid()) {
117                         printf("?Privileged command\n");
118                         continue;
119                 }
120                 (*c->c_handler)(margc, margv);
121         }
122         return 0;
123 }
124
125 void
126 intr(int signo)
127 {
128         if (!fromatty)
129                 exit(0);
130         longjmp(toplevel, 1);
131 }
132
133 static struct cmd *
134 getcmd(char *name)
135 {
136         char *p, *q;
137         struct cmd *c, *found;
138         int nmatches, longest;
139         extern int NCMDS;
140
141         longest = 0;
142         nmatches = 0;
143         found = 0;
144         for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
145                 p = c->c_name;
146                 for (q = name; *q == *p++; q++)
147                         if (*q == 0)            /* exact match? */
148                                 return(c);
149                 if (!*q) {                      /* the name was a prefix */
150                         if (q - name > longest) {
151                                 longest = q - name;
152                                 nmatches = 1;
153                                 found = c;
154                         } else if (q - name == longest)
155                                 nmatches++;
156                 }
157         }
158         if (nmatches > 1)
159                 return((struct cmd *)-1);
160         return(found);
161 }
162
163 /*
164  * Slice a string up into argc/argv.
165  */
166 void
167 makeargv(void)
168 {
169         char *cp;
170         char **argp = margv;
171
172         margc = 0;
173         for (cp = cmdline; margc < MAX_MARGV - 1 && *cp;) {
174                 while (isspace(*cp))
175                         cp++;
176                 if (*cp == '\0')
177                         break;
178                 *argp++ = cp;
179                 margc += 1;
180                 while (*cp != '\0' && !isspace(*cp))
181                         cp++;
182                 if (*cp == '\0')
183                         break;
184                 *cp++ = '\0';
185         }
186         *argp++ = 0;
187 }
188
189 #define HELPINDENT (sizeof("directory"))
190
191 /*
192  * Help command.
193  */
194 void
195 help(int argc, char **argv)
196 {
197         struct cmd *c;
198
199         if (argc == 1) {
200                 int i, j, w;
201                 int columns, width = 0, lines;
202                 extern int NCMDS;
203
204                 printf("Commands may be abbreviated.  Commands are:\n\n");
205                 for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
206                         int len = strlen(c->c_name);
207
208                         if (len > width)
209                                 width = len;
210                 }
211                 width = (width + 8) &~ 7;
212                 columns = 80 / width;
213                 if (columns == 0)
214                         columns = 1;
215                 lines = (NCMDS + columns - 1) / columns;
216                 for (i = 0; i < lines; i++) {
217                         for (j = 0; j < columns; j++) {
218                                 c = cmdtab + j * lines + i;
219                                 printf("%s", c->c_name);
220                                 if (c + lines >= &cmdtab[NCMDS]) {
221                                         printf("\n");
222                                         break;
223                                 }
224                                 w = strlen(c->c_name);
225                                 while (w < width) {
226                                         w = (w + 8) &~ 7;
227                                         putchar('\t');
228                                 }
229                         }
230                 }
231                 return;
232         }
233         while (--argc > 0) {
234                 char *arg;
235                 arg = *++argv;
236                 c = getcmd(arg);
237                 if (c == (struct cmd *)-1)
238                         printf("?Ambiguous help command %s\n", arg);
239                 else if (c == NULL)
240                         printf("?Invalid help command %s\n", arg);
241                 else
242                         printf("%-*s\t%s\n", (int)HELPINDENT,
243                                 c->c_name, c->c_help);
244         }
245 }