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 "drivers/FileSystemLike.h"
00024 #include "platform/PlatformMutex.h"
00025 
00026 namespace mbed {
00027 /** \addtogroup drivers */
00028 /** @{*/
00029 
00030 FILEHANDLE local_file_open(const char* name, int flags);
00031 
00032 class LocalFileHandle : public FileHandle {
00033 
00034 public:
00035     LocalFileHandle(FILEHANDLE fh);
00036 
00037     virtual int close();
00038 
00039     virtual ssize_t write(const void *buffer, size_t length);
00040 
00041     virtual ssize_t read(void *buffer, size_t length);
00042 
00043     virtual int isatty();
00044 
00045     virtual off_t lseek(off_t position, int whence);
00046 
00047     virtual int fsync();
00048 
00049     virtual off_t flen();
00050 
00051 protected:
00052     virtual void lock();
00053     virtual void unlock();
00054     FILEHANDLE _fh;
00055     int pos;
00056     PlatformMutex _mutex;
00057 };
00058 
00059 /** A filesystem for accessing the local mbed Microcontroller USB disk drive
00060  *
00061  *  This allows programs to read and write files on the same disk drive that is used to program the
00062  *  mbed Microcontroller. Once created, the standard C file access functions are used to open,
00063  *  read and write files.
00064  *
00065  * @Note Synchronization level: Thread safe
00066  *
00067  * Example:
00068  * @code
00069  * #include "mbed.h"
00070  *
00071  * LocalFileSystem local("local");               // Create the local filesystem under the name "local"
00072  *
00073  * int main() {
00074  *     FILE *fp = fopen("/local/out.txt", "w");  // Open "out.txt" on the local file system for writing
00075  *     fprintf(fp, "Hello World!");
00076  *     fclose(fp);
00077  *     remove("/local/out.txt");                 // Removes the file "out.txt" from the local file system
00078  *
00079  *     DIR *d = opendir("/local");               // Opens the root directory of the local file system
00080  *     struct dirent *p;
00081  *     while((p = readdir(d)) != NULL) {         // Print the names of the files in the local file system
00082  *       printf("%s\n", p->d_name);              // to stdout.
00083  *     }
00084  *     closedir(d);
00085  * }
00086  * @endcode
00087  *
00088  * @note
00089  *  If the microcontroller program makes an access to the local drive, it will be marked as "removed"
00090  *  on the Host computer. This means it is no longer accessible from the Host Computer.
00091  *
00092  *  The drive will only re-appear when the microcontroller program exists. Note that if the program does
00093  *  not exit, you will need to hold down reset on the mbed Microcontroller to be able to see the drive again!
00094  */
00095 class LocalFileSystem : public FileSystemLike {
00096     // No modifiable state
00097 
00098 public:
00099     LocalFileSystem(const char* n) : FileSystemLike(n) {
00100 
00101     }
00102 
00103     virtual FileHandle *open(const char* name, int flags);
00104     virtual int remove(const char *filename);
00105     virtual DirHandle *opendir(const char *name);
00106 };
00107 
00108 } // namespace mbed
00109 
00110 #endif
00111 
00112 #endif
00113 
00114 /** @}*/