Rtos API example

Revision:
0:9fca2b23d0ba
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os/features/filesystem/bd/HeapBlockDevice.cpp	Sat Feb 23 12:13:36 2019 +0000
@@ -0,0 +1,149 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2017 ARM Limited
+ *
+ * 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 "HeapBlockDevice.h"
+
+
+HeapBlockDevice::HeapBlockDevice(bd_size_t size, bd_size_t block)
+    : _read_size(block), _program_size(block), _erase_size(block)
+    , _count(size / block), _blocks(0)
+{
+    MBED_ASSERT(_count * _erase_size == size);
+}
+
+HeapBlockDevice::HeapBlockDevice(bd_size_t size, bd_size_t read, bd_size_t program, bd_size_t erase)
+    : _read_size(read), _program_size(program), _erase_size(erase)
+    , _count(size / erase), _blocks(0)
+{
+    MBED_ASSERT(_count * _erase_size == size);
+}
+
+HeapBlockDevice::~HeapBlockDevice()
+{
+    if (_blocks) {
+        for (size_t i = 0; i < _count; i++) {
+            free(_blocks[i]);
+        }
+
+        delete[] _blocks;
+        _blocks = 0;
+    }
+}
+
+int HeapBlockDevice::init()
+{
+    if (!_blocks) {
+        _blocks = new uint8_t*[_count];
+        for (size_t i = 0; i < _count; i++) {
+            _blocks[i] = 0;
+        }
+    }
+
+    return BD_ERROR_OK;
+}
+
+int HeapBlockDevice::deinit()
+{
+    MBED_ASSERT(_blocks != NULL);
+    // Memory is lazily cleaned up in destructor to allow
+    // data to live across de/reinitialization
+    return BD_ERROR_OK;
+}
+
+bd_size_t HeapBlockDevice::get_read_size() const
+{
+    MBED_ASSERT(_blocks != NULL);
+    return _read_size;
+}
+
+bd_size_t HeapBlockDevice::get_program_size() const
+{
+    MBED_ASSERT(_blocks != NULL);
+    return _program_size;
+}
+
+bd_size_t HeapBlockDevice::get_erase_size() const
+{
+    MBED_ASSERT(_blocks != NULL);
+    return _erase_size;
+}
+
+bd_size_t HeapBlockDevice::size() const
+{
+    MBED_ASSERT(_blocks != NULL);
+    return _count * _erase_size;
+}
+
+int HeapBlockDevice::read(void *b, bd_addr_t addr, bd_size_t size)
+{
+    MBED_ASSERT(_blocks != NULL);
+    MBED_ASSERT(is_valid_read(addr, size));
+    uint8_t *buffer = static_cast<uint8_t*>(b);
+
+    while (size > 0) {
+        bd_addr_t hi = addr / _erase_size;
+        bd_addr_t lo = addr % _erase_size;
+
+        if (_blocks[hi]) {
+            memcpy(buffer, &_blocks[hi][lo], _read_size);
+        } else {
+            memset(buffer, 0, _read_size);
+        }
+
+        buffer += _read_size;
+        addr += _read_size;
+        size -= _read_size;
+    }
+
+    return 0;
+}
+
+int HeapBlockDevice::program(const void *b, bd_addr_t addr, bd_size_t size)
+{
+    MBED_ASSERT(_blocks != NULL);
+    MBED_ASSERT(is_valid_program(addr, size));
+    const uint8_t *buffer = static_cast<const uint8_t*>(b);
+
+    while (size > 0) {
+        bd_addr_t hi = addr / _erase_size;
+        bd_addr_t lo = addr % _erase_size;
+
+        if (!_blocks[hi]) {
+            _blocks[hi] = (uint8_t*)malloc(_erase_size);
+            if (!_blocks[hi]) {
+                return BD_ERROR_DEVICE_ERROR;
+            }
+        }
+
+        memcpy(&_blocks[hi][lo], buffer, _program_size);
+
+        buffer += _program_size;
+        addr += _program_size;
+        size -= _program_size;
+    }
+
+    return 0;
+}
+
+int HeapBlockDevice::erase(bd_addr_t addr, bd_size_t size)
+{
+    MBED_ASSERT(_blocks != NULL);
+    MBED_ASSERT(is_valid_erase(addr, size));
+    // TODO assert on programming unerased blocks
+
+    return 0;
+}
+