LocalFileSystem.h

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