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diff --git a/lib/libpthread/thread/thr_create.c b/lib/libpthread/thread/thr_create.c
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+/*
+ * Copyright (c) 2003 Daniel M. Eischen <deischen@gdeb.com>
+ * Copyright (c) 1995-1998 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 AUTHOR 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.
+ *
+ * $FreeBSD$
+ */
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stddef.h>
+#include <sys/time.h>
+#include <machine/reg.h>
+#include <pthread.h>
+#include "thr_private.h"
+#include "libc_private.h"
+
+static void free_thread(struct pthread *curthread, struct pthread *thread);
+static int create_stack(struct pthread_attr *pattr);
+static void free_stack(struct pthread_attr *pattr);
+static void thread_start(struct pthread *curthread,
+ void *(*start_routine) (void *), void *arg);
+
+__weak_reference(_pthread_create, pthread_create);
+
+/*
+ * Some notes on new thread creation and first time initializion
+ * to enable multi-threading.
+ *
+ * There are basically two things that need to be done.
+ *
+ * 1) The internal library variables must be initialized.
+ * 2) Upcalls need to be enabled to allow multiple threads
+ * to be run.
+ *
+ * The first may be done as a result of other pthread functions
+ * being called. When _thr_initial is null, _libpthread_init is
+ * called to initialize the internal variables; this also creates
+ * or sets the initial thread. It'd be nice to automatically
+ * have _libpthread_init called on program execution so we don't
+ * have to have checks throughout the library.
+ *
+ * The second part is only triggered by the creation of the first
+ * thread (other than the initial/main thread). If the thread
+ * being created is a scope system thread, then a new KSE/KSEG
+ * pair needs to be allocated. Also, if upcalls haven't been
+ * enabled on the initial thread's KSE, they must be now that
+ * there is more than one thread; this could be delayed until
+ * the initial KSEG has more than one thread.
+ */
+int
+_pthread_create(pthread_t * thread, const pthread_attr_t * attr,
+ void *(*start_routine) (void *), void *arg)
+{
+ struct pthread *curthread, *new_thread;
+ struct kse *kse = NULL;
+ struct kse_group *kseg = NULL;
+ kse_critical_t crit;
+ int ret = 0;
+
+ if (_thr_initial == NULL)
+ _libpthread_init(NULL);
+
+ /*
+ * Turn on threaded mode, if failed, it is unnecessary to
+ * do further work.
+ */
+ if (_kse_isthreaded() == 0 && _kse_setthreaded(1)) {
+ return (EAGAIN);
+ }
+ curthread = _get_curthread();
+
+ /*
+ * Allocate memory for the thread structure.
+ * Some functions use malloc, so don't put it
+ * in a critical region.
+ */
+ if ((new_thread = _thr_alloc(curthread)) == NULL) {
+ /* Insufficient memory to create a thread: */
+ ret = EAGAIN;
+ } else {
+ /* Check if default thread attributes are required: */
+ if (attr == NULL || *attr == NULL)
+ /* Use the default thread attributes: */
+ new_thread->attr = _pthread_attr_default;
+ else {
+ new_thread->attr = *(*attr);
+ if ((*attr)->sched_inherit == PTHREAD_INHERIT_SCHED) {
+ /* inherit scheduling contention scop */
+ if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
+ new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
+ else
+ new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM;
+ /*
+ * scheduling policy and scheduling parameters will be
+ * inherited in following code.
+ */
+ }
+ }
+ if (_thread_scope_system != 0)
+ new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
+ if (create_stack(&new_thread->attr) != 0) {
+ /* Insufficient memory to create a stack: */
+ ret = EAGAIN;
+ _thr_free(curthread, new_thread);
+ }
+ else if (((new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) != 0) &&
+ (((kse = _kse_alloc(curthread, 1)) == NULL)
+ || ((kseg = _kseg_alloc(curthread)) == NULL))) {
+ /* Insufficient memory to create a new KSE/KSEG: */
+ ret = EAGAIN;
+ if (kse != NULL) {
+ kse->k_kcb->kcb_kmbx.km_flags |= KMF_DONE;
+ _kse_free(curthread, kse);
+ }
+ free_stack(&new_thread->attr);
+ _thr_free(curthread, new_thread);
+ }
+ else {
+ if (kseg != NULL) {
+ /* Add the KSE to the KSEG's list of KSEs. */
+ TAILQ_INSERT_HEAD(&kseg->kg_kseq, kse, k_kgqe);
+ kseg->kg_ksecount = 1;
+ kse->k_kseg = kseg;
+ kse->k_schedq = &kseg->kg_schedq;
+ }
+ /*
+ * Write a magic value to the thread structure
+ * to help identify valid ones:
+ */
+ new_thread->magic = THR_MAGIC;
+
+ new_thread->slice_usec = -1;
+ new_thread->start_routine = start_routine;
+ new_thread->arg = arg;
+ new_thread->cancelflags = PTHREAD_CANCEL_ENABLE |
+ PTHREAD_CANCEL_DEFERRED;
+
+ /* No thread is wanting to join to this one: */
+ new_thread->joiner = NULL;
+
+ /* Initialize the signal frame: */
+ new_thread->curframe = NULL;
+
+ /*
+ * Initialize the machine context.
+ * Enter a critical region to get consistent context.
+ */
+ crit = _kse_critical_enter();
+ THR_GETCONTEXT(&new_thread->tcb->tcb_tmbx.tm_context);
+ /* Initialize the thread for signals: */
+ new_thread->sigmask = curthread->sigmask;
+ _kse_critical_leave(crit);
+
+ new_thread->tcb->tcb_tmbx.tm_udata = new_thread;
+ new_thread->tcb->tcb_tmbx.tm_context.uc_sigmask =
+ new_thread->sigmask;
+ new_thread->tcb->tcb_tmbx.tm_context.uc_stack.ss_size =
+ new_thread->attr.stacksize_attr;
+ new_thread->tcb->tcb_tmbx.tm_context.uc_stack.ss_sp =
+ new_thread->attr.stackaddr_attr;
+ makecontext(&new_thread->tcb->tcb_tmbx.tm_context,
+ (void (*)(void))thread_start, 3, new_thread,
+ start_routine, arg);
+ /*
+ * Check if this thread is to inherit the scheduling
+ * attributes from its parent:
+ */
+ if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) {
+ /*
+ * Copy the scheduling attributes.
+ * Lock the scheduling lock to get consistent
+ * scheduling parameters.
+ */
+ THR_SCHED_LOCK(curthread, curthread);
+ new_thread->base_priority =
+ curthread->base_priority &
+ ~THR_SIGNAL_PRIORITY;
+ new_thread->attr.prio =
+ curthread->base_priority &
+ ~THR_SIGNAL_PRIORITY;
+ new_thread->attr.sched_policy =
+ curthread->attr.sched_policy;
+ THR_SCHED_UNLOCK(curthread, curthread);
+ } else {
+ /*
+ * Use just the thread priority, leaving the
+ * other scheduling attributes as their
+ * default values:
+ */
+ new_thread->base_priority =
+ new_thread->attr.prio;
+ }
+ new_thread->active_priority = new_thread->base_priority;
+ new_thread->inherited_priority = 0;
+
+ /* Initialize the mutex queue: */
+ TAILQ_INIT(&new_thread->mutexq);
+
+ /* Initialise hooks in the thread structure: */
+ new_thread->specific = NULL;
+ new_thread->specific_data_count = 0;
+ new_thread->cleanup = NULL;
+ new_thread->flags = 0;
+ new_thread->continuation = NULL;
+ new_thread->wakeup_time.tv_sec = -1;
+ new_thread->lock_switch = 0;
+ sigemptyset(&new_thread->sigpend);
+ new_thread->check_pending = 0;
+ new_thread->locklevel = 0;
+ new_thread->rdlock_count = 0;
+ new_thread->sigstk.ss_sp = 0;
+ new_thread->sigstk.ss_size = 0;
+ new_thread->sigstk.ss_flags = SS_DISABLE;
+ new_thread->oldsigmask = NULL;
+
+ if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) {
+ new_thread->state = PS_SUSPENDED;
+ new_thread->flags = THR_FLAGS_SUSPENDED;
+ }
+ else
+ new_thread->state = PS_RUNNING;
+
+ /*
+ * System scope threads have their own kse and
+ * kseg. Process scope threads are all hung
+ * off the main process kseg.
+ */
+ if ((new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) == 0) {
+ new_thread->kseg = _kse_initial->k_kseg;
+ new_thread->kse = _kse_initial;
+ }
+ else {
+ kse->k_curthread = NULL;
+ kse->k_kseg->kg_flags |= KGF_SINGLE_THREAD;
+ new_thread->kse = kse;
+ new_thread->kseg = kse->k_kseg;
+ kse->k_kcb->kcb_kmbx.km_udata = kse;
+ kse->k_kcb->kcb_kmbx.km_curthread = NULL;
+ }
+
+ /*
+ * Schedule the new thread starting a new KSEG/KSE
+ * pair if necessary.
+ */
+ ret = _thr_schedule_add(curthread, new_thread);
+ if (ret != 0)
+ free_thread(curthread, new_thread);
+ else {
+ /* Return a pointer to the thread structure: */
+ (*thread) = new_thread;
+ }
+ }
+ }
+
+ /* Return the status: */
+ return (ret);
+}
+
+static void
+free_thread(struct pthread *curthread, struct pthread *thread)
+{
+ free_stack(&thread->attr);
+ if ((thread->attr.flags & PTHREAD_SCOPE_SYSTEM) != 0) {
+ /* Free the KSE and KSEG. */
+ _kseg_free(thread->kseg);
+ _kse_free(curthread, thread->kse);
+ }
+ _thr_free(curthread, thread);
+}
+
+static int
+create_stack(struct pthread_attr *pattr)
+{
+ int ret;
+
+ /* Check if a stack was specified in the thread attributes: */
+ if ((pattr->stackaddr_attr) != NULL) {
+ pattr->guardsize_attr = 0;
+ pattr->flags |= THR_STACK_USER;
+ ret = 0;
+ }
+ else
+ ret = _thr_stack_alloc(pattr);
+ return (ret);
+}
+
+static void
+free_stack(struct pthread_attr *pattr)
+{
+ struct kse *curkse;
+ kse_critical_t crit;
+
+ if ((pattr->flags & THR_STACK_USER) == 0) {
+ crit = _kse_critical_enter();
+ curkse = _get_curkse();
+ KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
+ /* Stack routines don't use malloc/free. */
+ _thr_stack_free(pattr);
+ KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
+ _kse_critical_leave(crit);
+ }
+}
+
+static void
+thread_start(struct pthread *curthread, void *(*start_routine) (void *),
+ void *arg)
+{
+ /* Run the current thread's start routine with argument: */
+ pthread_exit(start_routine(arg));
+
+ /* This point should never be reached. */
+ PANIC("Thread has resumed after exit");
+}
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