scoutos / prex-0.9.0 / usr / lib / posix / process / waitpid.c @ 03e9c04a
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/*
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* Copyright (c) 2005, Kohsuke Ohtani
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the author nor the names of any co-contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/prex.h> |
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#include <sys/posix.h> |
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#include <ipc/proc.h> |
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#include <ipc/ipc.h> |
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#include <sys/wait.h> |
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#include <stddef.h> |
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#include <errno.h> |
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/*
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* If the target child task calls exit() just after we
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* send PS_WAITPID message, a process server will send an
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* exception to us. But, we can not catch the exception
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* before calling exception_wait().
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*/
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pid_t |
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waitpid(pid_t pid, int *status, int options) |
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{ |
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struct msg m;
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pid_t child; |
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int sig, error;
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thread_t self; |
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int pri;
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/* Boost current priority */
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self = thread_self(); |
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thread_getpri(self, &pri); |
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thread_setpri(self, pri - 1);
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for (;;) {
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m.hdr.code = PS_WAITPID; |
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m.data[0] = pid;
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m.data[1] = options;
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error = msg_send(__proc_obj, &m, sizeof(m));
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if (error == EINTR)
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continue;
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if (m.hdr.status) {
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errno = m.hdr.status; |
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return -1; |
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} |
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child = m.data[0];
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if (child != 0 || options & WNOHANG) |
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break;
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error = exception_wait(&sig); |
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if (error == EINTR) {
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errno = EINTR; |
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break;
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} |
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} |
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/* Restore priority */
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thread_setpri(self, pri); |
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if (status != NULL) |
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*status = m.data[1];
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return child;
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} |