/* vi: set sw=4 ts=4: */ /* * A _very_ simple clone based pthread-like implementation * * Copyright (C) 2001,2002 by Erik Andersen <andersee@debian.org> * * 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. * * You should have received a copy of the GNU Library General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <stdlib.h> #include <sched.h> #include <signal.h> #include <errno.h> #include <unistd.h> #include <pthread.h> #define STACKSIZE 8096 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */ #define CLONE_VM 0x00000100 /* set if VM shared between processes */ #define CLONE_FS 0x00000200 /* set if fs info shared between proces ses */ #define CLONE_FILES 0x00000400 /* set if open files shared between pro cesses */ #define CLONE_SIGHAND 0x00000800 /* set if signal handlers shared */ /* Lame home-grown clone based threading */ int pthread_mutex_init (pthread_mutex_t *mutex, const pthread_mutexattr_t *mutex_attr) { mutex->__m_lock.__spinlock = 1; return 0; } int pthread_mutex_lock (pthread_mutex_t *mutex) { while (mutex->__m_lock.__spinlock == 0) { usleep(10000); } --(mutex->__m_lock.__spinlock); return 0; } int pthread_mutex_unlock (pthread_mutex_t *mutex) { ++(mutex->__m_lock.__spinlock); return 0; } int pthread_cond_wait (pthread_cond_t *cond, pthread_mutex_t *mutex) { ++(mutex->__m_lock.__spinlock); while (cond->__c_lock.__spinlock == 0) { usleep(10000); } --(cond->__c_lock.__spinlock); return 0; } int pthread_cond_signal(pthread_cond_t *cond) { ++(cond->__c_lock.__spinlock); return 0; } int pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *cond_attr) { cond->__c_lock.__spinlock = 1; return 0; } int pthread_create(pthread_t *thread, const pthread_attr_t *attr, void* (*fn)(void *), void *data) { long retval; void **newstack; int (*clonefunc)(void *) = (int (*)(void *))(fn); newstack = (void **) malloc(STACKSIZE); if (!newstack) return -1; newstack = (void **) (STACKSIZE + (char *) newstack); *--newstack = data; retval = clone(clonefunc, newstack, CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND | SIGCHLD, data); if (retval < 0) { errno = -retval; *thread = 0; retval = -1; } else { *thread = retval; retval = 0; } return retval; } int pthread_join (pthread_t thread, void **thread_return) { int retval; /* Fixme -- wait for thread and get its return value */ retval = EXIT_SUCCESS; if (thread_return) (int)*thread_return = retval; _exit(retval); } link_warning(pthread_join, "pthread_join is a stub and does not behave properly"); void pthread_exit (void *retval) { _exit(*(int *)retval); }