ObservingBlockDevice.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2017-2017 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_OBSERVING_BLOCK_DEVICE_H
00023 #define MBED_OBSERVING_BLOCK_DEVICE_H
00024 
00025 #include "BlockDevice.h"
00026 #include "PlatformMutex.h"
00027 #include "Callback.h"
00028 
00029 
00030 class ObservingBlockDevice : public BlockDevice
00031 {
00032 public:
00033 
00034     /** Lifetime of the block device
00035      *
00036      * @param bd        Block device to observe
00037      */
00038     ObservingBlockDevice(BlockDevice *bd);
00039     virtual ~ObservingBlockDevice();
00040 
00041     /** Attach a callback which is called on change
00042      *
00043      *  @param cb       Function to call on filesystem change (erase or program)
00044      */
00045     void attach(mbed::Callback<void(BlockDevice *)> cb);
00046 
00047     /** Initialize a block device
00048      *
00049      *  @return         0 on success or a negative error code on failure
00050      */
00051     virtual int init();
00052 
00053     /** Deinitialize a block device
00054      *
00055      *  @return         0 on success or a negative error code on failure
00056      */
00057     virtual int deinit();
00058 
00059     /** Ensure data on storage is in sync with the driver
00060      *
00061      *  @return         0 on success or a negative error code on failure
00062      */
00063     virtual int sync();
00064 
00065     /** Read blocks from a block device
00066      *
00067      *  @param buffer   Buffer to read blocks into
00068      *  @param addr     Address of block to begin reading from
00069      *  @param size     Size to read in bytes, must be a multiple of read block size
00070      *  @return         0 on success, negative error code on failure
00071      */
00072     virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
00073 
00074     /** Program blocks to a block device
00075      *
00076      *  The blocks must have been erased prior to being programmed
00077      *
00078      *  @param buffer   Buffer of data to write to blocks
00079      *  @param addr     Address of block to begin writing to
00080      *  @param size     Size to write in bytes, must be a multiple of program block size
00081      *  @return         0 on success, negative error code on failure
00082      */
00083     virtual int program(const void *buffer, bd_addr_t addr, bd_size_t size);
00084 
00085     /** Erase blocks on a block device
00086      *
00087      *  The state of an erased block is undefined until it has been programmed,
00088      *  unless get_erase_value returns a non-negative byte value
00089      *
00090      *  @param addr     Address of block to begin erasing
00091      *  @param size     Size to erase in bytes, must be a multiple of erase block size
00092      *  @return         0 on success, negative error code on failure
00093      */
00094     virtual int erase(bd_addr_t addr, bd_size_t size);
00095 
00096     /** Get the size of a readable block
00097      *
00098      *  @return         Size of a readable block in bytes
00099      */
00100     virtual bd_size_t get_read_size() const;
00101 
00102     /** Get the size of a programmable block
00103      *
00104      *  @return         Size of a programmable block in bytes
00105      */
00106     virtual bd_size_t get_program_size() const;
00107 
00108     /** Get the size of an erasable block
00109      *
00110      *  @return         Size of an erasable block in bytes
00111      */
00112     virtual bd_size_t get_erase_size() const;
00113 
00114     /** Get the size of an erasable block given address
00115      *
00116      *  @param addr     Address within the erasable block
00117      *  @return         Size of an erasable block in bytes
00118      *  @note Must be a multiple of the program size
00119      */
00120     virtual bd_size_t get_erase_size(bd_addr_t addr) const;
00121 
00122     /** Get the value of storage when erased
00123      *
00124      *  If get_erase_value returns a non-negative byte value, the underlying
00125      *  storage is set to that value when erased, and storage containing
00126      *  that value can be programmed without another erase.
00127      *
00128      *  @return         The value of storage when erased, or -1 if you can't
00129      *                  rely on the value of erased storage
00130      */
00131     virtual int get_erase_value() const;
00132 
00133     /** Get the total size of the underlying device
00134      *
00135      *  @return         Size of the underlying device in bytes
00136      */
00137     virtual bd_size_t size() const;
00138 
00139 private:
00140     BlockDevice *_bd;
00141     mbed::Callback<void(BlockDevice *)> _change;
00142 };
00143 
00144 
00145 
00146 #endif