1 /* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements. See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License. You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "apr_arch_threadproc.h"
18
apr_proc_detach(int daemonize)19 APR_DECLARE(apr_status_t) apr_proc_detach(int daemonize)
20 {
21 if (chdir("/") == -1) {
22 return errno;
23 }
24
25 #if !defined(MPE) && !defined(OS2) && !defined(TPF) && !defined(BEOS)
26 /* Don't detach for MPE because child processes can't survive the death of
27 * the parent. */
28 if (daemonize) {
29 int x;
30
31 if ((x = fork()) > 0) {
32 exit(0);
33 }
34 else if (x == -1) {
35 perror("fork");
36 fprintf(stderr, "unable to fork new process\n");
37 exit(1); /* we can't do anything here, so just exit. */
38 }
39 /* RAISE_SIGSTOP(DETACH); */
40 }
41 #endif
42
43 #ifdef HAVE_SETSID
44 /* A setsid() failure is not fatal if we didn't just fork().
45 * The calling process may be the process group leader, in
46 * which case setsid() will fail with EPERM.
47 */
48 if (setsid() == -1 && daemonize) {
49 return errno;
50 }
51 #elif defined(NEXT) || defined(NEWSOS)
52 if (setpgrp(0, getpid()) == -1) {
53 return errno;
54 }
55 #elif defined(OS2) || defined(TPF) || defined(MPE)
56 /* do nothing */
57 #else
58 if (setpgid(0, 0) == -1) {
59 return errno;
60 }
61 #endif
62
63 /* close out the standard file descriptors */
64 if (freopen("/dev/null", "r", stdin) == NULL) {
65 return errno;
66 /* continue anyhow -- note we can't close out descriptor 0 because we
67 * have nothing to replace it with, and if we didn't have a descriptor
68 * 0 the next file would be created with that value ... leading to
69 * havoc.
70 */
71 }
72 if (freopen("/dev/null", "w", stdout) == NULL) {
73 return errno;
74 }
75 /* We are going to reopen this again in a little while to the error
76 * log file, but better to do it twice and suffer a small performance
77 * hit for consistancy than not reopen it here.
78 */
79 if (freopen("/dev/null", "w", stderr) == NULL) {
80 return errno;
81 }
82 return APR_SUCCESS;
83 }
84
85 #if (!HAVE_WAITPID)
86 /* From [email protected]
87 * this is not ideal but it works for SVR3 variants
88 * Modified by [email protected] to call wait3 instead of wait because
89 * apache started to use the WNOHANG option.
90 */
waitpid(pid_t pid,int * statusp,int options)91 int waitpid(pid_t pid, int *statusp, int options)
92 {
93 int tmp_pid;
94 if (kill(pid, 0) == -1) {
95 errno = ECHILD;
96 return -1;
97 }
98 while (((tmp_pid = wait3(statusp, options, 0)) != pid) &&
99 (tmp_pid != -1) && (tmp_pid != 0) && (pid != -1))
100 ;
101 return tmp_pid;
102 }
103 #endif
104
105