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 
00023 /** \addtogroup storage */
00024 /** @{*/
00025 
00026 #ifndef MBED_OBSERVING_BLOCK_DEVICE_H
00027 #define MBED_OBSERVING_BLOCK_DEVICE_H
00028 
00029 #include "BlockDevice.h"
00030 #include "platform/PlatformMutex.h"
00031 #include "platform/Callback.h"
00032 
00033 namespace mbed {
00034 
00035 class ObservingBlockDevice : public BlockDevice {
00036 public:
00037 
00038     /** Lifetime of the block device
00039      *
00040      * @param bd        Block device to observe
00041      */
00042     ObservingBlockDevice(BlockDevice *bd);
00043     virtual ~ObservingBlockDevice();
00044 
00045     /** Attach a callback which is called on change
00046      *
00047      *  @param cb       Function to call on filesystem change (erase or program)
00048      */
00049     void attach(mbed::Callback<void(BlockDevice *)> cb);
00050 
00051     /** Initialize a block device
00052      *
00053      *  @return         0 on success or a negative error code on failure
00054      */
00055     virtual int init();
00056 
00057     /** Deinitialize a block device
00058      *
00059      *  @return         0 on success or a negative error code on failure
00060      */
00061     virtual int deinit();
00062 
00063     /** Ensure data on storage is in sync with the driver
00064      *
00065      *  @return         0 on success or a negative error code on failure
00066      */
00067     virtual int sync();
00068 
00069     /** Read blocks from a block device
00070      *
00071      *  @param buffer   Buffer to read blocks into
00072      *  @param addr     Address of block to begin reading from
00073      *  @param size     Size to read in bytes, must be a multiple of read block size
00074      *  @return         0 on success, negative error code on failure
00075      */
00076     virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
00077 
00078     /** Program blocks to a block device
00079      *
00080      *  The blocks must have been erased prior to being programmed
00081      *
00082      *  @param buffer   Buffer of data to write to blocks
00083      *  @param addr     Address of block to begin writing to
00084      *  @param size     Size to write in bytes, must be a multiple of program block size
00085      *  @return         0 on success, negative error code on failure
00086      */
00087     virtual int program(const void *buffer, bd_addr_t addr, bd_size_t size);
00088 
00089     /** Erase blocks on a block device
00090      *
00091      *  The state of an erased block is undefined until it has been programmed,
00092      *  unless get_erase_value returns a non-negative byte value
00093      *
00094      *  @param addr     Address of block to begin erasing
00095      *  @param size     Size to erase in bytes, must be a multiple of erase block size
00096      *  @return         0 on success, negative error code on failure
00097      */
00098     virtual int erase(bd_addr_t addr, bd_size_t size);
00099 
00100     /** Get the size of a readable block
00101      *
00102      *  @return         Size of a readable block in bytes
00103      */
00104     virtual bd_size_t get_read_size() const;
00105 
00106     /** Get the size of a programmable block
00107      *
00108      *  @return         Size of a programmable block in bytes
00109      */
00110     virtual bd_size_t get_program_size() const;
00111 
00112     /** Get the size of an erasable block
00113      *
00114      *  @return         Size of an erasable block in bytes
00115      */
00116     virtual bd_size_t get_erase_size() const;
00117 
00118     /** Get the size of an erasable block given address
00119      *
00120      *  @param addr     Address within the erasable block
00121      *  @return         Size of an erasable block in bytes
00122      *  @note Must be a multiple of the program size
00123      */
00124     virtual bd_size_t get_erase_size(bd_addr_t addr) const;
00125 
00126     /** Get the value of storage when erased
00127      *
00128      *  If get_erase_value returns a non-negative byte value, the underlying
00129      *  storage is set to that value when erased, and storage containing
00130      *  that value can be programmed without another erase.
00131      *
00132      *  @return         The value of storage when erased, or -1 if you can't
00133      *                  rely on the value of erased storage
00134      */
00135     virtual int get_erase_value() const;
00136 
00137     /** Get the total size of the underlying device
00138      *
00139      *  @return         Size of the underlying device in bytes
00140      */
00141     virtual bd_size_t size() const;
00142 
00143     /** Get the BlockDevice class type.
00144      *
00145      *  @return         A string represent the BlockDevice class type.
00146      */
00147     virtual const char *get_type() const;
00148 
00149 private:
00150     BlockDevice *_bd;
00151     mbed::Callback<void(BlockDevice *)> _change;
00152 };
00153 
00154 } // namespace mbed
00155 
00156 // Added "using" for backwards compatibility
00157 #ifndef MBED_NO_GLOBAL_USING_DIRECTIVE
00158 using mbed::ObservingBlockDevice;
00159 #endif
00160 
00161 #endif
00162 
00163 /** @}*/