2 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by John Birrell.
16 * 4. Neither the name of the author nor the names of any co-contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 AUTHOR 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
32 * $FreeBSD: src/lib/libc_r/uthread/uthread_close.c,v 1.10.2.5 2003/06/13 16:04:59 ru Exp $
40 #include "pthread_private.h"
48 struct fd_table_entry *entry;
50 if ((fd < 0) || (fd >= _thread_dtablesize) ||
51 (fd == _thread_kern_pipe[0]) || (fd == _thread_kern_pipe[1]) ||
52 (_thread_fd_table[fd] == NULL)) {
54 * Don't allow silly programs to close the kernel pipe
55 * and non-active descriptors.
61 * Lock the file descriptor while the file is closed and get
62 * the file descriptor status:
64 else if (((ret = _FD_LOCK(fd, FD_RDWR, NULL)) == 0) &&
65 ((ret = __sys_fstat(fd, &sb)) == 0)) {
67 * Check if the file should be left as blocking.
69 * This is so that the file descriptors shared with a parent
70 * process aren't left set to non-blocking if the child
71 * closes them prior to exit. An example where this causes
72 * problems with /bin/sh is when a child closes stdin.
74 * Setting a file as blocking causes problems if a threaded
75 * parent accesses the file descriptor before the child exits.
76 * Once the threaded parent receives a SIGCHLD then it resets
77 * all of its files to non-blocking, and so it is then safe
80 * Pipes are not set to blocking when they are closed, as
81 * the parent and child will normally close the file
82 * descriptor of the end of the pipe that they are not
83 * using, which would then cause any reads to block
86 if ((S_ISREG(sb.st_mode) || S_ISCHR(sb.st_mode))
87 && (_thread_fd_getflags(fd) & O_NONBLOCK) == 0) {
88 /* Get the current flags: */
89 flags = __sys_fcntl(fd, F_GETFL, NULL);
90 /* Clear the nonblocking file descriptor flag: */
91 __sys_fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
94 /* XXX: Assumes well behaved threads. */
95 /* XXX: Defer real close to avoid race condition */
96 entry = _thread_fd_table[fd];
97 _thread_fd_table[fd] = NULL;
100 /* Drop stale pthread stdio descriptor flags. */
102 _pthread_stdio_flags[fd] = -1;
104 /* Close the file descriptor: */
105 ret = __sys_close(fd);
115 _thread_enter_cancellation_point();
117 _thread_leave_cancellation_point();