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authorAndreas Rottmann <a.rottmann@gmx.at>2010-05-27 18:23:15 +0200
committerAndreas Rottmann <a.rottmann@gmx.at>2010-05-27 18:23:15 +0200
commit3e0814cd9862b89c7a39672672937477bd87ddfb (patch)
tree159134a624e51509f40ed8823249f09a70d1dda3 /tests/glthread/thread.c
parent3bebb94360f1c2333feb8d504a9fa4f96984d8b7 (diff)
Imported Upstream version 0.9.3upstream/0.9.3
Diffstat (limited to 'tests/glthread/thread.c')
-rw-r--r--tests/glthread/thread.c218
1 files changed, 218 insertions, 0 deletions
diff --git a/tests/glthread/thread.c b/tests/glthread/thread.c
new file mode 100644
index 0000000..5237994
--- /dev/null
+++ b/tests/glthread/thread.c
@@ -0,0 +1,218 @@
+/* Creating and controlling threads.
+ Copyright (C) 2005-2010 Free Software Foundation, Inc.
+
+ 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 3, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2005.
+ Based on GCC's gthr-posix.h, gthr-posix95.h, gthr-solaris.h,
+ gthr-win32.h. */
+
+#include <config.h>
+
+/* Specification. */
+#include "glthread/thread.h"
+
+#include <stdlib.h>
+#include "glthread/lock.h"
+
+/* ========================================================================= */
+
+#if USE_WIN32_THREADS
+
+#include <process.h>
+
+/* -------------------------- gl_thread_t datatype -------------------------- */
+
+/* The Thread-Local Storage (TLS) key that allows to access each thread's
+ 'struct gl_thread_struct *' pointer. */
+static DWORD self_key = (DWORD)-1;
+
+/* Initializes self_key. This function must only be called once. */
+static void
+do_init_self_key (void)
+{
+ self_key = TlsAlloc ();
+ /* If this fails, we're hosed. */
+ if (self_key == (DWORD)-1)
+ abort ();
+}
+
+/* Initializes self_key. */
+static void
+init_self_key (void)
+{
+ gl_once_define(static, once)
+ gl_once (once, do_init_self_key);
+}
+
+/* This structure contains information about a thread.
+ It is stored in TLS under key self_key. */
+struct gl_thread_struct
+{
+ /* Fields for managing the handle. */
+ HANDLE volatile handle;
+ CRITICAL_SECTION handle_lock;
+ /* Fields for managing the exit value. */
+ void * volatile result;
+ /* Fields for managing the thread start. */
+ void * (*func) (void *);
+ void *arg;
+};
+
+/* Return a real HANDLE object for the current thread. */
+static inline HANDLE
+get_current_thread_handle (void)
+{
+ HANDLE this_handle;
+
+ /* GetCurrentThread() returns a pseudo-handle, i.e. only a symbolic
+ identifier, not a real handle. */
+ if (!DuplicateHandle (GetCurrentProcess (), GetCurrentThread (),
+ GetCurrentProcess (), &this_handle,
+ 0, FALSE, DUPLICATE_SAME_ACCESS))
+ abort ();
+ return this_handle;
+}
+
+gl_thread_t
+gl_thread_self_func (void)
+{
+ gl_thread_t thread;
+
+ if (self_key == (DWORD)-1)
+ init_self_key ();
+ thread = TlsGetValue (self_key);
+ if (thread == NULL)
+ {
+ /* This happens only in threads that have not been created through
+ glthread_create(), such as the main thread. */
+ for (;;)
+ {
+ thread =
+ (struct gl_thread_struct *)
+ malloc (sizeof (struct gl_thread_struct));
+ if (thread != NULL)
+ break;
+ /* Memory allocation failed. There is not much we can do. Have to
+ busy-loop, waiting for the availability of memory. */
+ Sleep (1);
+ }
+
+ thread->handle = get_current_thread_handle ();
+ InitializeCriticalSection (&thread->handle_lock);
+ thread->result = NULL; /* just to be deterministic */
+ TlsSetValue (self_key, thread);
+ }
+ return thread;
+}
+
+/* The main function of a freshly creating thread. It's a wrapper around
+ the FUNC and ARG arguments passed to glthread_create_func. */
+static unsigned int WINAPI
+wrapper_func (void *varg)
+{
+ struct gl_thread_struct *thread = (struct gl_thread_struct *)varg;
+
+ EnterCriticalSection (&thread->handle_lock);
+ /* Create a new handle for the thread only if the parent thread did not yet
+ fill in the handle. */
+ if (thread->handle == NULL)
+ thread->handle = get_current_thread_handle ();
+ LeaveCriticalSection (&thread->handle_lock);
+
+ if (self_key == (DWORD)-1)
+ init_self_key ();
+ TlsSetValue (self_key, thread);
+
+ /* Run the thread. Store the exit value if the thread was not terminated
+ otherwise. */
+ thread->result = thread->func (thread->arg);
+ return 0;
+}
+
+int
+glthread_create_func (gl_thread_t *threadp, void * (*func) (void *), void *arg)
+{
+ struct gl_thread_struct *thread =
+ (struct gl_thread_struct *) malloc (sizeof (struct gl_thread_struct));
+ if (thread == NULL)
+ return ENOMEM;
+ thread->handle = NULL;
+ InitializeCriticalSection (&thread->handle_lock);
+ thread->result = NULL; /* just to be deterministic */
+ thread->func = func;
+ thread->arg = arg;
+
+ {
+ unsigned int thread_id;
+ HANDLE thread_handle;
+
+ thread_handle = (HANDLE)
+ _beginthreadex (NULL, 100000, wrapper_func, thread, 0, &thread_id);
+ /* calls CreateThread with the same arguments */
+ if (thread_handle == NULL)
+ {
+ DeleteCriticalSection (&thread->handle_lock);
+ free (thread);
+ return EAGAIN;
+ }
+
+ EnterCriticalSection (&thread->handle_lock);
+ if (thread->handle == NULL)
+ thread->handle = thread_handle;
+ else
+ /* thread->handle was already set by the thread itself. */
+ CloseHandle (thread_handle);
+ LeaveCriticalSection (&thread->handle_lock);
+
+ *threadp = thread;
+ return 0;
+ }
+}
+
+int
+glthread_join_func (gl_thread_t thread, void **retvalp)
+{
+ if (thread == NULL)
+ return EINVAL;
+
+ if (thread == gl_thread_self ())
+ return EDEADLK;
+
+ if (WaitForSingleObject (thread->handle, INFINITE) == WAIT_FAILED)
+ return EINVAL;
+
+ if (retvalp != NULL)
+ *retvalp = thread->result;
+
+ DeleteCriticalSection (&thread->handle_lock);
+ CloseHandle (thread->handle);
+ free (thread);
+
+ return 0;
+}
+
+int
+gl_thread_exit_func (void *retval)
+{
+ gl_thread_t thread = gl_thread_self ();
+ thread->result = retval;
+ _endthreadex (0); /* calls ExitThread (0) */
+ abort ();
+}
+
+#endif
+
+/* ========================================================================= */