HeapBlockDevice.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2017 ARM Limited
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00020  * SOFTWARE.
00021  */
00022 #ifndef MBED_MEM_BLOCK_DEVICE_H
00023 #define MBED_MEM_BLOCK_DEVICE_H
00024 
00025 #include "BlockDevice.h"
00026 #include "mbed.h"
00027 
00028 
00029 /** Lazily allocated heap-backed block device
00030  *
00031  * Useful for simulating a block device and tests
00032  *
00033  * @code
00034  * #include "mbed.h"
00035  * #include "HeapBlockDevice.h"
00036  *
00037  * #define BLOCK_SIZE 512
00038  *
00039  * HeapBlockDevice bd(2048, BLOCK_SIZE); // 2048 bytes with a block size of 512 bytes
00040  * uint8_t block[BLOCK_SIZE] = "Hello World!\n";
00041  *
00042  * int main() {
00043  *     bd.init();
00044  *     bd.erase(0, BLOCK_SIZE);
00045  *     bd.program(block, 0, BLOCK_SIZE);
00046  *     bd.read(block, 0, BLOCK_SIZE);
00047  *     printf("%s", block);
00048  *     bd.deinit();
00049  * }
00050  * @endcode
00051  */
00052 class HeapBlockDevice : public BlockDevice
00053 {
00054 public:
00055 
00056     /** Lifetime of the memory block device
00057      *
00058      * @param size      Size of the Block Device in bytes
00059      * @param block     Block size in bytes. Minimum read, program, and erase sizes are
00060      *                  configured to this value
00061      */
00062     HeapBlockDevice(bd_size_t size, bd_size_t block=512);
00063     /** Lifetime of the memory block device
00064      *
00065      * @param size      Size of the Block Device in bytes
00066      * @param read      Minimum read size required in bytes
00067      * @param program   Minimum program size required in bytes
00068      * @param erase     Minimum erase size required in bytes
00069      */
00070     HeapBlockDevice(bd_size_t size, bd_size_t read, bd_size_t program, bd_size_t erase);
00071     virtual ~HeapBlockDevice();
00072 
00073     /** Initialize a block device
00074      *
00075      *  @return         0 on success or a negative error code on failure
00076      */
00077     virtual int init();
00078 
00079     /** Deinitialize a block device
00080      *
00081      *  @return         0 on success or a negative error code on failure
00082      */
00083     virtual int deinit();
00084 
00085     /** Read blocks from a block device
00086      *
00087      *  @param buffer   Buffer to read blocks into
00088      *  @param addr     Address of block to begin reading from
00089      *  @param size     Size to read in bytes, must be a multiple of read block size
00090      *  @return         0 on success, negative error code on failure
00091      */
00092     virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
00093 
00094     /** Program blocks to a block device
00095      *
00096      *  The blocks must have been erased prior to being programmed
00097      *
00098      *  @param buffer   Buffer of data to write to blocks
00099      *  @param addr     Address of block to begin writing to
00100      *  @param size     Size to write in bytes, must be a multiple of program block size
00101      *  @return         0 on success, negative error code on failure
00102      */
00103     virtual int program(const void *buffer, bd_addr_t addr, bd_size_t size);
00104 
00105     /** Erase blocks on a block device
00106      *
00107      *  The state of an erased block is undefined until it has been programmed
00108      *
00109      *  @param addr     Address of block to begin erasing
00110      *  @param size     Size to erase in bytes, must be a multiple of erase block size
00111      *  @return         0 on success, negative error code on failure
00112      */
00113     virtual int erase(bd_addr_t addr, bd_size_t size);
00114 
00115     /** Get the size of a readable block
00116      *
00117      *  @return         Size of a readable block in bytes
00118      */
00119     virtual bd_size_t get_read_size() const;
00120 
00121     /** Get the size of a programmable block
00122      *
00123      *  @return         Size of a programmable block in bytes
00124      */
00125     virtual bd_size_t get_program_size() const;
00126 
00127     /** Get the size of an erasable block
00128      *
00129      *  @return         Size of an erasable block in bytes
00130      */
00131     virtual bd_size_t get_erase_size() const;
00132 
00133     /** Get the size of an erasable block given address
00134      *
00135      *  @param addr     Address within the erasable block
00136      *  @return         Size of an erasable block in bytes
00137      *  @note Must be a multiple of the program size
00138      */
00139     virtual bd_size_t get_erase_size(bd_addr_t addr) const;
00140 
00141     /** Get the total size of the underlying device
00142      *
00143      *  @return         Size of the underlying device in bytes
00144      */
00145     virtual bd_size_t size() const;
00146 
00147 private:
00148     bd_size_t _read_size;
00149     bd_size_t _program_size;
00150     bd_size_t _erase_size;
00151     bd_size_t _count;
00152     uint8_t **_blocks;
00153 };
00154 
00155 
00156 #endif