xref: /freebsd/usr.bin/apply/apply.c (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
1 /*-
2  * Copyright (c) 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Jan-Simon Pendry.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 #if 0
39 static const char sccsid[] = "@(#)apply.c	8.4 (Berkeley) 4/4/94";
40 #endif
41 static const char rcsid[] =
42   "$FreeBSD$";
43 #endif /* not lint */
44 
45 #include <sys/types.h>
46 
47 #include <sys/wait.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <paths.h>
52 #include <signal.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 
58 void	usage __P((void));
59 int	system __P((const char *));
60 
61 int
62 main(argc, argv)
63 	int argc;
64 	char *argv[];
65 {
66 	int ch, clen, debug, i, l, magic, n, nargs, rval;
67 	char *c, *cmd, *p, *q;
68 
69 	debug = 0;
70 	magic = '%';		/* Default magic char is `%'. */
71 	nargs = -1;
72 	while ((ch = getopt(argc, argv, "a:d0123456789")) != -1)
73 		switch (ch) {
74 		case 'a':
75 			if (optarg[1] != '\0')
76 				errx(1,
77 				    "illegal magic character specification");
78 			magic = optarg[0];
79 			break;
80 		case 'd':
81 			debug = 1;
82 			break;
83 		case '0': case '1': case '2': case '3': case '4':
84 		case '5': case '6': case '7': case '8': case '9':
85 			if (nargs != -1)
86 				errx(1,
87 				    "only one -# argument may be specified");
88 			nargs = optopt - '0';
89 			break;
90 		default:
91 			usage();
92 		}
93 	argc -= optind;
94 	argv += optind;
95 
96 	if (argc < 2)
97 		usage();
98 
99 	/*
100 	 * The command to run is argv[0], and the args are argv[1..].
101 	 * Look for %digit references in the command, remembering the
102 	 * largest one.
103 	 */
104 	for (n = 0, p = argv[0]; *p != '\0'; ++p)
105 		if (p[0] == magic && isdigit(p[1]) && p[1] != '0') {
106 			++p;
107 			if (p[0] - '0' > n)
108 				n = p[0] - '0';
109 		}
110 
111 	/*
112 	 * If there were any %digit references, then use those, otherwise
113 	 * build a new command string with sufficient %digit references at
114 	 * the end to consume (nargs) arguments each time round the loop.
115 	 * Allocate enough space to hold the maximum command.
116 	 */
117 	if ((cmd = malloc(sizeof("exec ") - 1 +
118 	    strlen(argv[0]) + 9 * (sizeof(" %1") - 1) + 1)) == NULL)
119 		err(1, NULL);
120 
121 	if (n == 0) {
122 		/* If nargs not set, default to a single argument. */
123 		if (nargs == -1)
124 			nargs = 1;
125 
126 		p = cmd;
127 		p += sprintf(cmd, "exec %s", argv[0]);
128 		for (i = 1; i <= nargs; i++)
129 			p += sprintf(p, " %c%d", magic, i);
130 
131 		/*
132 		 * If nargs set to the special value 0, eat a single
133 		 * argument for each command execution.
134 		 */
135 		if (nargs == 0)
136 			nargs = 1;
137 	} else {
138 		(void)sprintf(cmd, "exec %s", argv[0]);
139 		nargs = n;
140 	}
141 
142 	/*
143 	 * Grab some space in which to build the command.  Allocate
144 	 * as necessary later, but no reason to build it up slowly
145 	 * for the normal case.
146 	 */
147 	if ((c = malloc(clen = 1024)) == NULL)
148 		err(1, NULL);
149 
150 	/*
151 	 * (argc) and (argv) are still offset by one to make it simpler to
152 	 * expand %digit references.  At the end of the loop check for (argc)
153 	 * equals 1 means that all the (argv) has been consumed.
154 	 */
155 	for (rval = 0; argc > nargs; argc -= nargs, argv += nargs) {
156 		/*
157 		 * Find a max value for the command length, and ensure
158 		 * there's enough space to build it.
159 		 */
160 		for (l = strlen(cmd), i = 0; i < nargs; i++)
161 			l += strlen(argv[i+1]);
162 		if (l > clen && (c = realloc(c, clen = l)) == NULL)
163 			err(1, NULL);
164 
165 		/* Expand command argv references. */
166 		for (p = cmd, q = c; *p != '\0'; ++p)
167 			if (p[0] == magic && isdigit(p[1]) && p[1] != '0')
168 				q += sprintf(q, "%s", argv[(++p)[0] - '0']);
169 			else
170 				*q++ = *p;
171 
172 		/* Terminate the command string. */
173 		*q = '\0';
174 
175 		/* Run the command. */
176 		if (debug)
177 			(void)printf("%s\n", c);
178 		else
179 			if (system(c))
180 				rval = 1;
181 	}
182 
183 	if (argc != 1)
184 		errx(1, "expecting additional argument%s after \"%s\"",
185 		    (nargs - argc) ? "s" : "", argv[argc - 1]);
186 	exit(rval);
187 }
188 
189 /*
190  * system --
191  * 	Private version of system(3).  Use the user's SHELL environment
192  *	variable as the shell to execute.
193  */
194 int
195 system(command)
196 	const char *command;
197 {
198 	static char *name, *shell;
199 	pid_t pid;
200 	int omask, pstat;
201 	sig_t intsave, quitsave;
202 
203 	if (shell == NULL) {
204 		if ((shell = getenv("SHELL")) == NULL)
205 			shell = _PATH_BSHELL;
206 		if ((name = strrchr(shell, '/')) == NULL)
207 			name = shell;
208 		else
209 			++name;
210 	}
211 	if (!command)		/* just checking... */
212 		return(1);
213 
214 	omask = sigblock(sigmask(SIGCHLD));
215 	switch(pid = vfork()) {
216 	case -1:			/* error */
217 		err(1, "vfork");
218 	case 0:				/* child */
219 		(void)sigsetmask(omask);
220 		execl(shell, name, "-c", command, NULL);
221 		warn("%s", shell);
222 		_exit(1);
223 	}
224 	intsave = signal(SIGINT, SIG_IGN);
225 	quitsave = signal(SIGQUIT, SIG_IGN);
226 	pid = waitpid(pid, &pstat, 0);
227 	(void)sigsetmask(omask);
228 	(void)signal(SIGINT, intsave);
229 	(void)signal(SIGQUIT, quitsave);
230 	return(pid == -1 ? -1 : pstat);
231 }
232 
233 void
234 usage()
235 {
236 
237 	(void)fprintf(stderr,
238 	"usage: apply [-a magic] [-d] [-0123456789] command arguments ...\n");
239 	exit(1);
240 }
241