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