freebsd-skq/lib/libc_r/uthread/uthread_create.c
julian 529743d354 Reviewed by: julian
Submitted by:	 john birrel

One version of the pthreads library
another will follow with differnt actions under some cases..
not QUITE complete
1996-01-22 00:23:58 +00:00

278 lines
8.6 KiB
C

/*
* 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 <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/time.h>
#ifdef _THREAD_SAFE
#include <machine/reg.h>
#include <pthread.h>
#include "pthread_private.h"
int
_thread_create(pthread_t * thread, const pthread_attr_t * attr,
void *(*start_routine) (void *), void *arg, pthread_t parent)
{
int i;
int ret = 0;
int status;
pthread_t new_thread;
void *stack;
/* Block signals: */
_thread_kern_sig_block(&status);
/* Allocate memory for the thread structure: */
if ((new_thread = (pthread_t) malloc(sizeof(struct pthread))) == NULL) {
/* Insufficient memory to create a thread: */
ret = EAGAIN;
} else {
/* Check if default thread attributes are required: */
if (attr == NULL) {
/* Use the default thread attributes: */
attr = &pthread_attr_default;
}
/* Check if a stack was specified in the thread attributes: */
if ((stack = attr->stackaddr_attr) != NULL) {
}
/* Allocate memory for the stack: */
else if ((stack = (void *) malloc(attr->stacksize_attr)) == NULL) {
/* Insufficient memory to create a thread: */
ret = EAGAIN;
free(new_thread);
}
/* Check for errors: */
if (ret != 0) {
} else {
/* Initialise the thread structure: */
memset(new_thread, 0, sizeof(struct pthread));
new_thread->slice_usec = -1;
new_thread->sig_saved = 0;
new_thread->stack = stack;
new_thread->start_routine = start_routine;
new_thread->arg = arg;
if (attr->suspend == PTHREAD_CREATE_SUSPENDED) {
new_thread->state = PS_SUSPENDED;
} else {
new_thread->state = PS_RUNNING;
}
/* Initialise the thread for signals: */
new_thread->sigmask = _thread_run->sigmask;
/*
* Enter a loop to initialise the signal handler
* array:
*/
for (i = 1; i < NSIG; i++) {
/* Default the signal handler: */
sigfillset(&new_thread->act[i - 1].sa_mask);
new_thread->act[i - 1].sa_handler = _thread_run->act[i - 1].sa_handler;
new_thread->act[i - 1].sa_flags = _thread_run->act[i - 1].sa_flags;
}
/* Initialise the jump buffer: */
_thread_sys_setjmp(new_thread->saved_jmp_buf);
/*
* Set up new stack frame so that it looks like it
* returned from a longjmp() to the beginning of
* _thread_start(). Check if this is a user thread:
*/
if (parent == NULL) {
/* Use the user start function: */
#if defined(__FreeBSD__)
new_thread->saved_jmp_buf[0]._jb[0] = (long) _thread_start;
#elif defined(__NetBSD__)
#if defined(__alpha)
new_thread->saved_jmp_buf[2] = (long) _thread_start;
new_thread->saved_jmp_buf[4 + R_RA] = 0;
new_thread->saved_jmp_buf[4 + R_T12] = (long) _thread_start;
#else
new_thread->saved_jmp_buf[0] = (long) _thread_start;
#endif
#else
#error "Don't recognize this operating system!"
#endif
} else {
/*
* Use the (funny) signal handler start
* function:
*/
#if defined(__FreeBSD__)
new_thread->saved_jmp_buf[0]._jb[0] = (int) _thread_start_sig_handler;
#elif defined(__NetBSD__)
#if defined(__alpha)
new_thread->saved_jmp_buf[2] = (long) _thread_start_sig_handler;
new_thread->saved_jmp_buf[4 + R_RA] = 0;
new_thread->saved_jmp_buf[4 + R_T12] = (long) _thread_start_sig_handler;
#else
new_thread->saved_jmp_buf[0] = (long) _thread_start_sig_handler;
#endif
#else
#error "Don't recognize this operating system!"
#endif
}
/* The stack starts high and builds down: */
#if defined(__FreeBSD__)
new_thread->saved_jmp_buf[0]._jb[2] = (int) (new_thread->stack + attr->stacksize_attr - sizeof(double));
#elif defined(__NetBSD__)
#if defined(__alpha)
new_thread->saved_jmp_buf[4 + R_SP] = (long) new_thread->stack + attr->stacksize_attr - sizeof(double);
#else
new_thread->saved_jmp_buf[2] = (long) new_thread->stack + attr->stacksize_attr - sizeof(double);
#endif
#else
#error "Don't recognize this operating system!"
#endif
/* Copy the thread attributes: */
memcpy(&new_thread->attr, attr, sizeof(pthread_attr_t));
/*
* Check if this thread is to inherit the scheduling
* attributes from its parent:
*/
if (new_thread->attr.flags & PTHREAD_INHERIT_SCHED) {
/* Copy the scheduling attributes: */
new_thread->pthread_priority = _thread_run->pthread_priority;
new_thread->attr.prio = _thread_run->pthread_priority;
new_thread->attr.schedparam_policy = _thread_run->attr.schedparam_policy;
} else {
/*
* Use just the thread priority, leaving the
* other scheduling attributes as their
* default values:
*/
new_thread->pthread_priority = new_thread->attr.prio;
}
/* Initialise the join queue for the new thread: */
_thread_queue_init(&(new_thread->join_queue));
/* Initialise hooks in the thread structure: */
new_thread->specific_data = NULL;
new_thread->cleanup = NULL;
new_thread->queue = NULL;
new_thread->qnxt = NULL;
new_thread->parent_thread = parent;
new_thread->flags = 0;
/* Add the thread to the linked list of all threads: */
new_thread->nxt = _thread_link_list;
_thread_link_list = new_thread;
/* Return a pointer to the thread structure: */
(*thread) = new_thread;
/* Check if a parent thread was specified: */
if (parent != NULL) {
/*
* A parent thread was specified, so this is
* a signal handler thread which must now
* wait for the signal handler to complete:
*/
parent->state = PS_SIGTHREAD;
} else {
/* Schedule the new user thread: */
_thread_kern_sched(NULL);
}
}
}
/* Unblock signals: */
_thread_kern_sig_unblock(status);
/* Return the status: */
return (ret);
}
int
pthread_create(pthread_t * thread, const pthread_attr_t * attr,
void *(*start_routine) (void *), void *arg)
{
int ret = 0;
/*
* Call the low level thread creation function which allows a parent
* thread to be specified:
*/
ret = _thread_create(thread, attr, start_routine, arg, NULL);
/* Return the status: */
return (ret);
}
void
_thread_start(void)
{
/* Run the current thread's start routine with argument: */
pthread_exit(_thread_run->start_routine(_thread_run->arg));
/* This point should never be reached. */
PANIC("Thread has resumed after exit");
}
void
_thread_start_sig_handler(void)
{
int sig;
long arg;
void (*sig_routine) (int);
/*
* Cast the argument from 'void *' to a variable that is NO SMALLER
* than a pointer (otherwise gcc under NetBSD/Alpha will complain):
*/
arg = (long) _thread_run->arg;
/* Cast the argument as a signal number: */
sig = (int) arg;
/* Cast a pointer to the signal handler function: */
sig_routine = (void (*) (int)) _thread_run->start_routine;
/* Call the signal handler function: */
(*sig_routine) (sig);
/* Exit the signal handler thread: */
pthread_exit(&arg);
/* This point should never be reached. */
PANIC("Signal handler thread has resumed after exit");
}
#endif