Annotation of src/usr.bin/nohup/nohup.c, Revision 1.18
1.18 ! bluhm 1: /* $OpenBSD: nohup.c,v 1.17 2018/04/26 12:42:51 guenther Exp $ */
1.1 deraadt 2: /* $NetBSD: nohup.c,v 1.6 1995/08/31 23:35:25 jtc Exp $ */
3:
4: /*
5: * Copyright (c) 1989 The Regents of the University of California.
6: * 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.
1.12 millert 16: * 3. Neither the name of the University nor the names of its contributors
1.1 deraadt 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/stat.h>
34: #include <fcntl.h>
35: #include <unistd.h>
36: #include <signal.h>
37: #include <stdio.h>
38: #include <stdlib.h>
39: #include <string.h>
40: #include <errno.h>
1.15 deraadt 41: #include <limits.h>
1.7 mickey 42: #include <err.h>
1.1 deraadt 43:
1.11 cloder 44: static void dofile(void);
45: __dead static void usage(void);
1.1 deraadt 46:
1.11 cloder 47: /*
48: * nohup shall exit with one of the following values:
49: * 126 - The utility was found but could not be invoked.
50: * 127 - An error occurred in the nohup utility, or the utility could
51: * not be found.
52: */
1.1 deraadt 53: #define EXIT_NOEXEC 126
54: #define EXIT_NOTFOUND 127
55: #define EXIT_MISC 127
56:
1.11 cloder 57: /*
58: * If the standard output is a terminal, all output written to
59: * its standard output shall be appended to the end of the file
60: * nohup.out in the current directory. If nohup.out cannot be
61: * created or opened for appending, the output shall be appended
62: * to the end of the file nohup.out in the directory specified
63: * by the HOME environment variable.
64: *
65: * If a file is created, the file's permission bits shall be
66: * set to S_IRUSR | S_IWUSR.
67: */
68: #define FILENAME "nohup.out"
69:
1.1 deraadt 70: int
1.11 cloder 71: main(int argc, char *argv[])
1.1 deraadt 72: {
73: int exit_status;
74:
1.16 deraadt 75: if (pledge("stdio rpath wpath cpath exec", NULL) == -1)
76: err(1, "pledge");
77:
1.1 deraadt 78: if (argc < 2)
79: usage();
80:
1.18 ! bluhm 81: if (isatty(STDOUT_FILENO) || errno == EBADF)
1.1 deraadt 82: dofile();
1.16 deraadt 83:
84: if (pledge("stdio exec", NULL) == -1)
85: err(1, "pledge");
86:
1.18 ! bluhm 87: if ((isatty(STDERR_FILENO) || errno == EBADF) &&
! 88: dup2(STDOUT_FILENO, STDERR_FILENO) == -1) {
1.1 deraadt 89: /* may have just closed stderr */
90: (void)fprintf(stdin, "nohup: %s\n", strerror(errno));
91: exit(EXIT_MISC);
92: }
93:
1.11 cloder 94: /*
95: * The nohup utility shall take the standard action for all signals
96: * except that SIGHUP shall be ignored.
97: */
1.1 deraadt 98: (void)signal(SIGHUP, SIG_IGN);
99:
100: execvp(argv[1], &argv[1]);
1.5 deraadt 101: exit_status = (errno == ENOENT) ? EXIT_NOTFOUND : EXIT_NOEXEC;
1.10 cloder 102: err(exit_status, "%s", argv[1]);
1.1 deraadt 103: }
104:
105: static void
1.11 cloder 106: dofile(void)
1.1 deraadt 107: {
108: int fd;
1.11 cloder 109: const char *p;
1.15 deraadt 110: char path[PATH_MAX];
1.1 deraadt 111:
112: p = FILENAME;
113: if ((fd = open(p, O_RDWR|O_CREAT|O_APPEND, S_IRUSR|S_IWUSR)) >= 0)
114: goto dupit;
1.6 millert 115: if ((p = getenv("HOME")) != NULL && *p != '\0' &&
1.3 millert 116: (strlen(p) + strlen(FILENAME) + 1) < sizeof(path)) {
1.11 cloder 117: (void)strlcpy(path, p, sizeof(path));
118: (void)strlcat(path, "/", sizeof(path));
119: (void)strlcat(path, FILENAME, sizeof(path));
1.1 deraadt 120: if ((fd = open(p = path, O_RDWR|O_CREAT|O_APPEND, S_IRUSR|S_IWUSR)) >= 0)
121: goto dupit;
122: }
1.7 mickey 123: errx(EXIT_MISC, "can't open a nohup.out file");
1.1 deraadt 124:
1.11 cloder 125: dupit:
126: (void)lseek(fd, (off_t)0, SEEK_END);
1.7 mickey 127: if (dup2(fd, STDOUT_FILENO) == -1)
128: err(EXIT_MISC, NULL);
1.18 ! bluhm 129: if (fd > STDERR_FILENO)
! 130: (void)close(fd);
1.1 deraadt 131: (void)fprintf(stderr, "sending output to %s\n", p);
132: }
133:
1.11 cloder 134: __dead static void
135: usage(void)
1.1 deraadt 136: {
1.13 sobrado 137: (void)fprintf(stderr, "usage: nohup utility [arg ...]\n");
1.1 deraadt 138: exit(EXIT_MISC);
139: }