Initial first (lame) pass at making a pthreads library. This

works for me when linking staticly on x86.

1 files changed, 106 insertions, 0 deletions

diff --git a/libpthread/pthread.c b/libpthread/pthread.c
new file mode 100644
index 000000000..a7e5ba10e
--- /dev/null
+++ b/libpthread/pthread.c
@@ -0,0 +1,106 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * A simple clopne based pthread implementation
+ *
+ * Copyright (C) 2001 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 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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;
+}
+