LocalFileSystem.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 #ifndef MBED_LOCALFILESYSTEM_H
00018 #define MBED_LOCALFILESYSTEM_H
00019 
00020 #include "platform/platform.h"
00021 
00022 #if DEVICE_LOCALFILESYSTEM
00023 
00024 #include "platform/FileSystemLike.h"
00025 #include "platform/PlatformMutex.h"
00026 #include "platform/NonCopyable.h"
00027 
00028 namespace mbed {
00029 /** \addtogroup platform */
00030 /** @{*/
00031 /**
00032  * \defgroup platform_LocalFileSystem LocalFileSystem functions
00033  * @{
00034  */
00035 
00036 FILEHANDLE local_file_open(const char *name, int flags);
00037 
00038 /**
00039  * @class LocalFileHandle
00040  * @ingroup platform
00041  */
00042 class LocalFileHandle : public FileHandle, private NonCopyable<LocalFileHandle> {
00043 
00044 public:
00045     LocalFileHandle(FILEHANDLE fh);
00046 
00047     virtual int close();
00048 
00049     virtual ssize_t write(const void *buffer, size_t length);
00050 
00051     virtual ssize_t read(void *buffer, size_t length);
00052 
00053     virtual int isatty();
00054 
00055     virtual off_t seek(off_t position, int whence);
00056 
00057     virtual int sync();
00058 
00059     virtual off_t size();
00060 
00061 protected:
00062     virtual void lock();
00063     virtual void unlock();
00064     FILEHANDLE _fh;
00065     int pos;
00066     PlatformMutex _mutex;
00067 };
00068 
00069 /** A filesystem for accessing the local mbed Microcontroller USB disk drive
00070  *
00071  *  This allows programs to read and write files on the same disk drive that is used to program the
00072  *  mbed Microcontroller. Once created, the standard C file access functions are used to open,
00073  *  read and write files.
00074  *
00075  * @note Synchronization level: Thread safe
00076  *
00077  * Example:
00078  * @code
00079  * #include "mbed.h"
00080  *
00081  * LocalFileSystem local("local");               // Create the local filesystem under the name "local"
00082  *
00083  * int main() {
00084  *     FILE *fp = fopen("/local/out.txt", "w");  // Open "out.txt" on the local file system for writing
00085  *     fprintf(fp, "Hello World!");
00086  *     fclose(fp);
00087  *     remove("/local/out.txt");                 // Removes the file "out.txt" from the local file system
00088  *
00089  *     DIR *d = opendir("/local");               // Opens the root directory of the local file system
00090  *     struct dirent *p;
00091  *     while((p = readdir(d)) != NULL) {         // Print the names of the files in the local file system
00092  *       printf("%s\n", p->d_name);              // to stdout.
00093  *     }
00094  *     closedir(d);
00095  * }
00096  * @endcode
00097  *
00098  * @note
00099  *  If the microcontroller program makes an access to the local drive, it will be marked as "removed"
00100  *  on the Host computer. This means it is no longer accessible from the Host Computer.
00101  *
00102  *  The drive will only re-appear when the microcontroller program exists. Note that if the program does
00103  *  not exit, you will need to hold down reset on the mbed Microcontroller to be able to see the drive again!
00104  * @ingroup platform
00105  */
00106 class LocalFileSystem : public FileSystemLike, private NonCopyable<LocalFileSystem> {
00107     // No modifiable state
00108 
00109 public:
00110     LocalFileSystem(const char *n) : FileSystemLike(n)
00111     {
00112 
00113     }
00114 
00115     virtual int open(FileHandle **file, const char *path, int flags);
00116     virtual int open(DirHandle **dir, const char *name);
00117     virtual int remove(const char *filename);
00118 };
00119 
00120 /**@}*/
00121 
00122 /**@}*/
00123 
00124 } // namespace mbed
00125 
00126 #endif
00127 
00128 #endif
00129