Diff: mbed/platform/CThunkBase.h

Revision:

0:d383e2dee0f7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed/platform/CThunkBase.h	Mon Jul 06 17:18:59 2020 +0530
@@ -0,0 +1,78 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2018-2018 ARM Limited
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __CTHUNK_BASE_H__
+#define __CTHUNK_BASE_H__
+
+/* IRQ/Exception compatible thunk entry function */
+typedef void (*CThunkEntry)(void);
+
+class CThunkBase {
+protected:
+    typedef void (*Trampoline)(CThunkBase *);
+
+    Trampoline _trampoline;
+
+    /*
+     * Allocate a CThunkEntry which can be called without arguments
+     *
+     * Calling the CThunkEntry invokes the _trampoline of the
+     * given cthunk. This function traps if there are no more
+     * free thunks.
+     */
+    static CThunkEntry cthunk_alloc(CThunkBase *cthunk);
+
+    /*
+     * Free a cthunk_entry so it can be reused
+     */
+    static void cthunk_free(CThunkEntry cthunk_entry);
+
+private:
+    typedef void (*CthunkFree)(CThunkEntry cthunk_entry);
+
+    /*
+     * Table of thunk functions
+     */
+    static const CThunkEntry _thunk_table[MBED_CONF_PLATFORM_CTHUNK_COUNT_MAX];
+
+    /*
+     * Table of active CThunk classes
+     */
+    static CThunkBase *_thunk_storage[MBED_CONF_PLATFORM_CTHUNK_COUNT_MAX];
+
+    /*
+     * Lazily initialized free function pointer
+     */
+    static CthunkFree _cthunk_free_real;
+
+    /*
+     * Actual free function
+     */
+    static void cthunk_free_real(CThunkEntry cthunk_entry);
+
+    /*
+     * Template function which stored in the _thunk_table
+     */
+    template<int N>
+    static void thunk_entry()
+    {
+        _thunk_storage[N]->_trampoline(_thunk_storage[N]);
+    }
+};
+
+#endif/*__CTHUNK_BASE_H__*/
+