Import Mbed OS hard-float snapshot

drivers/source/usb/LinkedListBase.cpp

@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2018-2019, Arm Limited and affiliates.
+ * 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.
+ */
+
+#include "LinkedList.h"
+#include "LinkEntry.h"
+#include "mbed_assert.h"
+
+LinkedListBase::LinkedListBase(): _head(0), _tail(0)
+{
+
+}
+
+LinkedListBase::~LinkedListBase()
+{
+
+}
+
+LinkEntry *LinkedListBase::head()
+{
+    return _head;
+}
+
+void LinkedListBase::enqueue(LinkEntry *entry)
+{
+    entry->_next = NULL;
+    if (_tail == NULL) {
+        _head = entry;
+    } else {
+        _tail->_next = entry;
+    }
+    _tail = entry;
+}
+
+LinkEntry *LinkedListBase::dequeue()
+{
+    if (_head == NULL) {
+        return NULL;
+    }
+    if (_head->_next == NULL) {
+        _tail = NULL;
+    }
+    LinkEntry *entry = _head;
+    _head = _head->_next;
+    entry->_next = NULL;
+    return entry;
+}
+
+void LinkedListBase::remove(LinkEntry *entry)
+{
+    LinkEntry *prev = NULL;
+    LinkEntry *cur = _head;
+    while (cur != entry) {
+        if (cur == NULL) {
+            // Element is not in the list
+            return;
+        }
+        prev = cur;
+        cur = cur->_next;
+    }
+
+    if (prev != NULL) {
+        prev->_next = entry->_next;
+    }
+    if (entry == _head) {
+        _head = entry->_next;
+    }
+    if (entry == _tail) {
+        _tail = prev;
+    }
+    entry->_next = NULL;
+}