diff options
Diffstat (limited to 'linuxthreads/join.c')
| -rw-r--r-- | linuxthreads/join.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/linuxthreads/join.c b/linuxthreads/join.c new file mode 100644 index 0000000..2bdc189 --- /dev/null +++ b/linuxthreads/join.c @@ -0,0 +1,145 @@ +/* Linuxthreads - a simple clone()-based implementation of Posix */ +/* threads for Linux. */ +/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ +/* */ +/* This program is free software; you can redistribute it and/or */ +/* modify it under the terms of the GNU Library General Public License */ +/* as published by the Free Software Foundation; either version 2 */ +/* of the License, or (at your option) any later version. */ +/* */ +/* This program is distributed in the hope that it will be useful, */ +/* but WITHOUT ANY WARRANTY; without even the implied warranty of */ +/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ +/* GNU Library General Public License for more details. */ + +/* Thread termination and joining */ + +#include <errno.h> +#include <sched.h> +#include <unistd.h> +#include "pthread.h" +#include "internals.h" +#include "spinlock.h" +#include "restart.h" + +void pthread_exit(void * retval) +{ + pthread_descr self = thread_self(); + pthread_descr joining; + struct pthread_request request; + + /* Reset the cancellation flag to avoid looping if the cleanup handlers + contain cancellation points */ + self->p_canceled = 0; + /* Call cleanup functions and destroy the thread-specific data */ + __pthread_perform_cleanup(); + __pthread_destroy_specifics(); + /* Store return value */ + acquire(self->p_spinlock); + self->p_retval = retval; + /* Say that we've terminated */ + self->p_terminated = 1; + /* See if someone is joining on us */ + joining = self->p_joining; + release(self->p_spinlock); + /* Restart joining thread if any */ + if (joining != NULL) restart(joining); + /* If this is the initial thread, block until all threads have terminated. + If another thread calls exit, we'll be terminated from our signal + handler. */ + if (self == __pthread_main_thread && __pthread_manager_request >= 0) { + request.req_thread = self; + request.req_kind = REQ_MAIN_THREAD_EXIT; + __libc_write(__pthread_manager_request, (char *)&request, sizeof(request)); + suspend(self); + } + /* Exit the process (but don't flush stdio streams, and don't run + atexit functions). */ + _exit(0); +} + +int pthread_join(pthread_t thread_id, void ** thread_return) +{ + volatile pthread_descr self = thread_self(); + struct pthread_request request; + pthread_handle handle = thread_handle(thread_id); + pthread_descr th; + + acquire(&handle->h_spinlock); + if (invalid_handle(handle, thread_id)) { + release(&handle->h_spinlock); + return ESRCH; + } + th = handle->h_descr; + if (th == self) { + release(&handle->h_spinlock); + return EDEADLK; + } + /* If detached or already joined, error */ + if (th->p_detached || th->p_joining != NULL) { + release(&handle->h_spinlock); + return EINVAL; + } + /* If not terminated yet, suspend ourselves. */ + if (! th->p_terminated) { + th->p_joining = self; + release(&handle->h_spinlock); + suspend_with_cancellation(self); + /* This is a cancellation point */ + if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) { + th->p_joining = NULL; + pthread_exit(PTHREAD_CANCELED); + } + acquire(&handle->h_spinlock); + } + /* Get return value */ + if (thread_return != NULL) *thread_return = th->p_retval; + release(&handle->h_spinlock); + /* Send notification to thread manager */ + if (__pthread_manager_request >= 0) { + request.req_thread = self; + request.req_kind = REQ_FREE; + request.req_args.free.thread = th; + __libc_write(__pthread_manager_request, + (char *) &request, sizeof(request)); + } + return 0; +} + +int pthread_detach(pthread_t thread_id) +{ + int terminated; + struct pthread_request request; + pthread_handle handle = thread_handle(thread_id); + pthread_descr th; + + acquire(&handle->h_spinlock); + if (invalid_handle(handle, thread_id)) { + release(&handle->h_spinlock); + return ESRCH; + } + th = handle->h_descr; + /* If already detached, error */ + if (th->p_detached) { + release(&handle->h_spinlock); + return EINVAL; + } + /* If already joining, don't do anything. */ + if (th->p_joining != NULL) { + release(&handle->h_spinlock); + return 0; + } + /* Mark as detached */ + th->p_detached = 1; + terminated = th->p_terminated; + release(&handle->h_spinlock); + /* If already terminated, notify thread manager to reclaim resources */ + if (terminated && __pthread_manager_request >= 0) { + request.req_thread = thread_self(); + request.req_kind = REQ_FREE; + request.req_args.free.thread = th; + __libc_write(__pthread_manager_request, + (char *) &request, sizeof(request)); + } + return 0; +} |