diff options
Diffstat (limited to 'lib/libpthread/pthreads/pthread.c')
| -rw-r--r-- | lib/libpthread/pthreads/pthread.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/lib/libpthread/pthreads/pthread.c b/lib/libpthread/pthreads/pthread.c new file mode 100644 index 000000000000..6a039d2d67d9 --- /dev/null +++ b/lib/libpthread/pthreads/pthread.c @@ -0,0 +1,200 @@ +/* ==== pthread.c ============================================================ + * Copyright (c) 1993, 1994 by Chris Provenzano, proven@mit.edu + * 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 Chris Provenzano. + * 4. The name of Chris Provenzano may not be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``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 CHRIS PROVENZANO 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. + * + * Description : Pthread functions. + * + * 1.00 93/07/26 proven + * -Started coding this file. + */ + +#include "pthread.h" +#include <signal.h> +#include <errno.h> + +/* + * These first functions really should not be called by the user. + */ + +/* ========================================================================== + * pthread_init() + * + * This function should be called in crt0.o before main() is called. + * But on some systems It may not be possible to change crt0.o so currently + * I'm requiring this function to be called first thing after main. + * Actually I'm assuming it is, because I do no locking here. + */ +void pthread_init(void) +{ + struct machdep_pthread machdep_data = MACHDEP_PTHREAD_INIT; + + /* Initialize the first thread */ + if (pthread_initial = (pthread_t)malloc(sizeof(struct pthread))) { + memcpy(&(pthread_initial->machdep_data), &machdep_data, sizeof(machdep_data)); + pthread_initial->state = PS_RUNNING; + pthread_initial->queue = NULL; + pthread_initial->next = NULL; + pthread_initial->pll = NULL; + + pthread_initial->lock = SEMAPHORE_CLEAR; + pthread_initial->error = 0; + + pthread_link_list = pthread_initial; + pthread_run = pthread_initial; + + /* Initialize the signal handler. */ + sig_init(); + + /* Initialize the fd table. */ + fd_init(); + + return; + } + PANIC(); +} + +/* ========================================================================== + * pthread_yield() + */ +void pthread_yield() +{ + sig_handler_fake(SIGVTALRM); +} + +/* ======================================================================= */ +/* ========================================================================== + * pthread_self() + */ +pthread_t pthread_self() +{ + return(pthread_run); +} + +/* ========================================================================== + * pthread_equal() + */ +int pthread_equal(pthread_t t1, pthread_t t2) +{ + return(t1 == t2); +} + +/* ========================================================================== + * pthread_exit() + */ +void pthread_exit(void *status) +{ + semaphore *lock, *plock; + pthread_t pthread; + + lock = &pthread_run->lock; + if (SEMAPHORE_TEST_AND_SET(lock)) { + pthread_yield(); + } + + /* Save return value */ + pthread_run->ret = status; + + /* First execute all cleanup handlers */ + + + /* + * Are there any threads joined to this one, + * if so wake them and let them detach this thread. + */ + if (pthread = pthread_queue_get(&(pthread_run->join_queue))) { + /* The current thread pthread_run can't be detached */ + plock = &(pthread->lock); + while (SEMAPHORE_TEST_AND_SET(plock)) { + pthread_yield(); + } + (void)pthread_queue_deq(&(pthread_run->join_queue)); + pthread->state = PS_RUNNING; + + /* Thread will unlock itself in pthread_join() */ + } + + /* This thread will never run again */ + reschedule(PS_DEAD); + PANIC(); +} + +/* ========================================================================== + * pthread_create() + * + * After the new thread structure is allocated and set up, it is added to + * pthread_run_next_queue, which requires a sig_prevent(), + * sig_check_and_resume() + */ +int pthread_create(pthread_t *thread, const pthread_attr_t *attr, + void * (*start_routine)(void *), void *arg) +{ + long nsec = 100000000; + void *stack; + + if ((*thread) = (pthread_t)malloc(sizeof(struct pthread))) { + + if (! attr) { attr = &pthread_default_attr; } + + /* Get a stack, if necessary */ + if ((stack = attr->stackaddr_attr) || + (stack = (void *)malloc(attr->stacksize_attr))) { + + machdep_pthread_create(&((*thread)->machdep_data), + start_routine, arg, 65536, stack, nsec); + + memcpy(&(*thread)->attr, attr, sizeof(pthread_attr_t)); + + (*thread)->queue = NULL; + (*thread)->next = NULL; + + (*thread)->lock = SEMAPHORE_CLEAR; + (*thread)->error = 0; + + sig_prevent(); + + /* Add to the link list of all threads. */ + (*thread)->pll = pthread_link_list; + pthread_link_list = (*thread); + + (*thread)->state = PS_RUNNING; + sig_check_and_resume(); + + return(OK); + } + free((*thread)); + } + return(ENOMEM); +} + +/* ========================================================================== + * pthread_cancel() + * + * This routine will also require a sig_prevent/sig_check_and_resume() + */ |