diff options
Diffstat (limited to 'lib/libc_r/uthread/uthread_fork.c')
-rw-r--r-- | lib/libc_r/uthread/uthread_fork.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/lib/libc_r/uthread/uthread_fork.c b/lib/libc_r/uthread/uthread_fork.c new file mode 100644 index 0000000..6e7ca0d --- /dev/null +++ b/lib/libc_r/uthread/uthread_fork.c @@ -0,0 +1,90 @@ +/* + * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by John Birrell. + * 4. Neither the name of the author nor the names of any co-contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + */ +#include <errno.h> +#include <fcntl.h> +#ifdef _THREAD_SAFE +#include <pthread.h> +#include "pthread_private.h" + +pid_t +fork(void) +{ + int flags; + pid_t ret; + + /* Fork a new process: */ + if ((ret = _thread_sys_fork()) <= 0) { + /* Parent process or error. Nothing to do here. */ + } else { + /* Close the pthread kernel pipe: */ + _thread_sys_close(_thread_kern_pipe[0]); + _thread_sys_close(_thread_kern_pipe[1]); + + /* Reset signals pending for the running thread: */ + memset(_thread_run->sigpend, 0, sizeof(_thread_run->sigpend)); + + /* + * Create a pipe that is written to by the signal handler to + * prevent signals being missed in calls to + * _thread_sys_select: + */ + if (_thread_sys_pipe(_thread_kern_pipe) != 0) { + /* Cannot create pipe, so abort: */ + PANIC("Cannot create pthread kernel pipe for forked process"); + } + /* Get the flags for the read pipe: */ + else if ((flags = _thread_sys_fcntl(_thread_kern_pipe[0], F_GETFL, NULL)) == -1) { + /* Abort this application: */ + abort(); + } + /* Make the read pipe non-blocking: */ + else if (_thread_sys_fcntl(_thread_kern_pipe[0], F_SETFL, flags | O_NONBLOCK) == -1) { + /* Abort this application: */ + abort(); + } + /* Get the flags for the write pipe: */ + else if ((flags = _thread_sys_fcntl(_thread_kern_pipe[1], F_GETFL, NULL)) == -1) { + /* Abort this application: */ + abort(); + } + /* Make the write pipe non-blocking: */ + else if (_thread_sys_fcntl(_thread_kern_pipe[1], F_SETFL, flags | O_NONBLOCK) == -1) { + /* Abort this application: */ + abort(); + } + } + + /* Return the process ID: */ + return (ret); +} +#endif |