xref: /freebsd/usr.bin/apply/apply.c (revision 8e6b01171e30297084bb0b4457c4183c2746aacc)
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 static char sccsid[] = "@(#)apply.c	8.4 (Berkeley) 4/4/94";
39 #endif /* not lint */
40 
41 #include <sys/wait.h>
42 
43 #include <ctype.h>
44 #include <err.h>
45 #include <paths.h>
46 #include <signal.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <unistd.h>
51 
52 void	usage __P((void));
53 int	system __P((const char *));
54 
55 int
56 main(argc, argv)
57 	int argc;
58 	char *argv[];
59 {
60 	int ch, clen, debug, i, l, magic, n, nargs, rval;
61 	char *c, *cmd, *p, *q;
62 
63 	debug = 0;
64 	magic = '%';		/* Default magic char is `%'. */
65 	nargs = -1;
66 	while ((ch = getopt(argc, argv, "a:d0123456789")) != EOF)
67 		switch (ch) {
68 		case 'a':
69 			if (optarg[1] != '\0')
70 				errx(1,
71 				    "illegal magic character specification.");
72 			magic = optarg[0];
73 			break;
74 		case 'd':
75 			debug = 1;
76 			break;
77 		case '0': case '1': case '2': case '3': case '4':
78 		case '5': case '6': case '7': case '8': case '9':
79 			if (nargs != -1)
80 				errx(1,
81 				    "only one -# argument may be specified.");
82 			nargs = optopt - '0';
83 			break;
84 		default:
85 			usage();
86 		}
87 	argc -= optind;
88 	argv += optind;
89 
90 	if (argc < 2)
91 		usage();
92 
93 	/*
94 	 * The command to run is argv[0], and the args are argv[1..].
95 	 * Look for %digit references in the command, remembering the
96 	 * largest one.
97 	 */
98 	for (n = 0, p = argv[0]; *p != '\0'; ++p)
99 		if (p[0] == magic && isdigit(p[1]) && p[1] != '0') {
100 			++p;
101 			if (p[0] - '0' > n)
102 				n = p[0] - '0';
103 		}
104 
105 	/*
106 	 * If there were any %digit references, then use those, otherwise
107 	 * build a new command string with sufficient %digit references at
108 	 * the end to consume (nargs) arguments each time round the loop.
109 	 * Allocate enough space to hold the maximum command.
110 	 */
111 	if ((cmd = malloc(sizeof("exec ") - 1 +
112 	    strlen(argv[0]) + 9 * (sizeof(" %1") - 1) + 1)) == NULL)
113 		err(1, NULL);
114 
115 	if (n == 0) {
116 		/* If nargs not set, default to a single argument. */
117 		if (nargs == -1)
118 			nargs = 1;
119 
120 		p = cmd;
121 		p += sprintf(cmd, "exec %s", argv[0]);
122 		for (i = 1; i <= nargs; i++)
123 			p += sprintf(p, " %c%d", magic, i);
124 
125 		/*
126 		 * If nargs set to the special value 0, eat a single
127 		 * argument for each command execution.
128 		 */
129 		if (nargs == 0)
130 			nargs = 1;
131 	} else {
132 		(void)sprintf(cmd, "exec %s", argv[0]);
133 		nargs = n;
134 	}
135 
136 	/*
137 	 * Grab some space in which to build the command.  Allocate
138 	 * as necessary later, but no reason to build it up slowly
139 	 * for the normal case.
140 	 */
141 	if ((c = malloc(clen = 1024)) == NULL)
142 		err(1, NULL);
143 
144 	/*
145 	 * (argc) and (argv) are still offset by one to make it simpler to
146 	 * expand %digit references.  At the end of the loop check for (argc)
147 	 * equals 1 means that all the (argv) has been consumed.
148 	 */
149 	for (rval = 0; argc > nargs; argc -= nargs, argv += nargs) {
150 		/*
151 		 * Find a max value for the command length, and ensure
152 		 * there's enough space to build it.
153 		 */
154 		for (l = strlen(cmd), i = 0; i < nargs; i++)
155 			l += strlen(argv[i]);
156 		if (l > clen && (c = realloc(c, clen = l)) == NULL)
157 			err(1, NULL);
158 
159 		/* Expand command argv references. */
160 		for (p = cmd, q = c; *p != '\0'; ++p)
161 			if (p[0] == magic && isdigit(p[1]) && p[1] != '0')
162 				q += sprintf(q, "%s", argv[(++p)[0] - '0']);
163 			else
164 				*q++ = *p;
165 
166 		/* Terminate the command string. */
167 		*q = '\0';
168 
169 		/* Run the command. */
170 		if (debug)
171 			(void)printf("%s\n", c);
172 		else
173 			if (system(c))
174 				rval = 1;
175 	}
176 
177 	if (argc != 1)
178 		errx(1, "expecting additional argument%s after \"%s\"",
179 		    (nargs - argc) ? "s" : "", argv[argc - 1]);
180 	exit(rval);
181 }
182 
183 /*
184  * system --
185  * 	Private version of system(3).  Use the user's SHELL environment
186  *	variable as the shell to execute.
187  */
188 int
189 system(command)
190 	const char *command;
191 {
192 	static char *name, *shell;
193 	union wait pstat;
194 	pid_t pid;
195 	int omask;
196 	sig_t intsave, quitsave;
197 
198 	if (shell == NULL) {
199 		if ((shell = getenv("SHELL")) == NULL)
200 			shell = _PATH_BSHELL;
201 		if ((name = strrchr(shell, '/')) == NULL)
202 			name = shell;
203 		else
204 			++name;
205 	}
206 	if (!command)		/* just checking... */
207 		return(1);
208 
209 	omask = sigblock(sigmask(SIGCHLD));
210 	switch(pid = vfork()) {
211 	case -1:			/* error */
212 		err(1, "fork");
213 	case 0:				/* child */
214 		(void)sigsetmask(omask);
215 		execl(shell, name, "-c", command, NULL);
216 		err(1, "%s", shell);
217 	}
218 	intsave = signal(SIGINT, SIG_IGN);
219 	quitsave = signal(SIGQUIT, SIG_IGN);
220 	pid = waitpid(pid, (int *)&pstat, 0);
221 	(void)sigsetmask(omask);
222 	(void)signal(SIGINT, intsave);
223 	(void)signal(SIGQUIT, quitsave);
224 	return(pid == -1 ? -1 : pstat.w_status);
225 }
226 
227 void
228 usage()
229 {
230 
231 	(void)fprintf(stderr,
232 	    "usage: apply [-a magic] [-0123456789] command arguments ...\n");
233 	exit(1);
234 }
235