initial commit of experimental Phoenix code

git-svn-id: https://svn.wxwidgets.org/svn/wx/sandbox/trunk/Phoenix@66111 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

sip/siplib/threads.c

@@ -0,0 +1,226 @@
+/*
+ * Thread support for the SIP library.  This module provides the hooks for
+ * C++ classes that provide a thread interface to interact properly with the
+ * Python threading infrastructure.
+ *
+ * Copyright (c) 2010 Riverbank Computing Limited <info@riverbankcomputing.com>
+ *
+ * This file is part of SIP.
+ *
+ * This copy of SIP is licensed for use under the terms of the SIP License
+ * Agreement.  See the file LICENSE for more details.
+ *
+ * This copy of SIP may also used under the terms of the GNU General Public
+ * License v2 or v3 as published by the Free Software Foundation which can be
+ * found in the files LICENSE-GPL2 and LICENSE-GPL3 included in this package.
+ *
+ * SIP is supplied WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+
+#include "sip.h"
+#include "sipint.h"
+
+
+/*
+ * The data associated with pending request to wrap an object.
+ */
+typedef struct _pendingDef {
+    void *cpp;                      /* The C/C++ object ot be wrapped. */
+    sipWrapper *owner;              /* The owner of the object. */
+    int flags;                      /* The flags. */
+} pendingDef;
+
+
+#ifdef WITH_THREAD
+
+#include <pythread.h>
+
+
+/*
+ * The per thread data we need to maintain.
+ */
+typedef struct _threadDef {
+    long thr_ident;                 /* The thread identifier. */
+    pendingDef pending;             /* An object waiting to be wrapped. */
+    struct _threadDef *next;        /* Next in the list. */
+} threadDef;
+
+
+static threadDef *threads = NULL;   /* Linked list of threads. */
+
+
+static threadDef *currentThreadDef(void);
+
+#endif
+
+
+static pendingDef pending;          /* An object waiting to be wrapped. */
+
+
+/*
+ * Get the address of any C/C++ object waiting to be wrapped.
+ */
+void *sipGetPending(sipWrapper **op, int *fp)
+{
+    pendingDef *pp;
+
+#ifdef WITH_THREAD
+    threadDef *thread;
+
+    if ((thread = currentThreadDef()) != NULL)
+        pp = &thread->pending;
+    else
+        pp = &pending;
+#else
+    pp = &pending;
+#endif
+
+    if (pp->cpp != NULL)
+    {
+        if (op != NULL)
+            *op = pp->owner;
+
+        if (fp != NULL)
+            *fp = pp->flags;
+    }
+
+    return pp->cpp;
+}
+
+
+/*
+ * Convert a new C/C++ pointer to a Python instance.
+ */
+PyObject *sipWrapSimpleInstance(void *cppPtr, const sipTypeDef *td,
+        sipWrapper *owner, int flags)
+{
+    static PyObject *nullargs = NULL;
+
+    pendingDef old_pending;
+    PyObject *self;
+#ifdef WITH_THREAD
+    threadDef *thread;
+#endif
+
+    if (nullargs == NULL && (nullargs = PyTuple_New(0)) == NULL)
+        return NULL;
+
+    if (cppPtr == NULL)
+    {
+        Py_INCREF(Py_None);
+        return Py_None;
+    }
+
+    /*
+     * Object creation can trigger the Python garbage collector which in turn
+     * can execute arbitrary Python code which can then call this function
+     * recursively.  Therefore we save any existing pending object before
+     * setting the new one.
+     */
+#ifdef WITH_THREAD
+    if ((thread = currentThreadDef()) != NULL)
+    {
+        old_pending = thread->pending;
+
+        thread->pending.cpp = cppPtr;
+        thread->pending.owner = owner;
+        thread->pending.flags = flags;
+    }
+    else
+    {
+        old_pending = pending;
+
+        pending.cpp = cppPtr;
+        pending.owner = owner;
+        pending.flags = flags;
+    }
+#else
+    old_pending = pending;
+
+    pending.cpp = cppPtr;
+    pending.owner = owner;
+    pending.flags = flags;
+#endif
+
+    self = PyObject_Call((PyObject *)sipTypeAsPyTypeObject(td), nullargs, NULL);
+
+#ifdef WITH_THREAD
+    if (thread != NULL)
+        thread->pending = old_pending;
+    else
+        pending = old_pending;
+#else
+    pending = old_pending;
+#endif
+
+    return self;
+}
+
+
+/*
+ * This is called from a newly created thread to initialise some thread local
+ * storage.
+ */
+void sip_api_start_thread(void)
+{
+#ifdef WITH_THREAD
+    threadDef *thread;
+
+    /* Save the thread ID.  First, find an empty slot in the list. */
+    for (thread = threads; thread != NULL; thread = thread->next)
+        if (thread->thr_ident == 0)
+            break;
+
+    if (thread == NULL)
+    {
+        thread = sip_api_malloc(sizeof (threadDef));
+        thread->next = threads;
+        threads = thread;
+    }
+
+    if (thread != NULL)
+    {
+        thread->thr_ident = PyThread_get_thread_ident();
+        thread->pending.cpp = NULL;
+    }
+#endif
+}
+
+
+/*
+ * Handle the termination of a thread.  The thread state should already have
+ * been handled by the last call to PyGILState_Release().
+ */
+void sip_api_end_thread(void)
+{
+#ifdef WITH_THREAD
+    threadDef *thread;
+
+    /* We have the GIL at this point. */
+    if ((thread = currentThreadDef()) != NULL)
+        thread->thr_ident = 0;
+#endif
+}
+
+
+#ifdef WITH_THREAD
+
+/*
+ * Return the thread data for the current thread or NULL if it wasn't
+ * recognised.
+ */
+static threadDef *currentThreadDef(void)
+{
+    threadDef *thread;
+    long ident = PyThread_get_thread_ident();
+
+    for (thread = threads; thread != NULL; thread = thread->next)
+        if (thread->thr_ident == ident)
+            break;
+
+    return thread;
+}
+
+#endif