xref: /openbsd/usr.bin/tee/tee.c (revision 73471bf0)
1 /*	$OpenBSD: tee.c,v 1.14 2021/12/13 18:33:23 cheloha Exp $	*/
2 /*	$NetBSD: tee.c,v 1.5 1994/12/09 01:43:39 jtc Exp $	*/
3 
4 /*
5  * Copyright (c) 1988, 1993
6  *	The Regents of the University of California.  All rights reserved.
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. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/types.h>
34 #include <sys/stat.h>
35 #include <sys/queue.h>
36 
37 #include <err.h>
38 #include <errno.h>
39 #include <fcntl.h>
40 #include <signal.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 
46 #define BSIZE (64 * 1024)
47 
48 struct list {
49 	SLIST_ENTRY(list) next;
50 	int fd;
51 	char *name;
52 };
53 SLIST_HEAD(, list) head;
54 
55 static void
56 add(int fd, char *name)
57 {
58 	struct list *p;
59 
60 	if ((p = malloc(sizeof(*p))) == NULL)
61 		err(1, NULL);
62 	p->fd = fd;
63 	p->name = name;
64 	SLIST_INSERT_HEAD(&head, p, next);
65 }
66 
67 int
68 main(int argc, char *argv[])
69 {
70 	struct list *p;
71 	int fd;
72 	ssize_t n, rval, wval;
73 	int append, ch, exitval;
74 	char *buf;
75 
76 	if (pledge("stdio wpath cpath", NULL) == -1)
77 		err(1, "pledge");
78 
79 	SLIST_INIT(&head);
80 
81 	append = 0;
82 	while ((ch = getopt(argc, argv, "ai")) != -1) {
83 		switch(ch) {
84 		case 'a':
85 			append = 1;
86 			break;
87 		case 'i':
88 			(void)signal(SIGINT, SIG_IGN);
89 			break;
90 		default:
91 			(void)fprintf(stderr, "usage: tee [-ai] [file ...]\n");
92 			return 1;
93 		}
94 	}
95 	argv += optind;
96 	argc -= optind;
97 
98 	add(STDOUT_FILENO, "stdout");
99 
100 	exitval = 0;
101 	while (*argv) {
102 		if ((fd = open(*argv, O_WRONLY | O_CREAT |
103 		    (append ? O_APPEND : O_TRUNC), DEFFILEMODE)) == -1) {
104 			warn("%s", *argv);
105 			exitval = 1;
106 		} else
107 			add(fd, *argv);
108 		argv++;
109 	}
110 
111 	if (pledge("stdio", NULL) == -1)
112 		err(1, "pledge");
113 
114 	buf = malloc(BSIZE);
115 	if (buf == NULL)
116 		err(1, NULL);
117 	while ((rval = read(STDIN_FILENO, buf, BSIZE)) > 0) {
118 		SLIST_FOREACH(p, &head, next) {
119 			for (n = 0; n < rval; n += wval) {
120 				wval = write(p->fd, buf + n, rval - n);
121 				if (wval == -1) {
122 					warn("%s", p->name);
123 					exitval = 1;
124 					break;
125 				}
126 			}
127 		}
128 	}
129 	free(buf);
130 	if (rval == -1) {
131 		warn("read");
132 		exitval = 1;
133 	}
134 
135 	SLIST_FOREACH(p, &head, next) {
136 		if (close(p->fd) == -1) {
137 			warn("%s", p->name);
138 			exitval = 1;
139 		}
140 	}
141 
142 	return exitval;
143 }
144