Dir.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2015 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 
00017 #ifndef DIR_H
00018 #define DIR_H
00019 
00020 #include "filesystem/FileSystem.h"
00021 #include "platform/DirHandle.h"
00022 
00023 namespace mbed {
00024 /** \addtogroup filesystem */
00025 /** @{*/
00026 
00027 
00028 /** Dir class
00029  */
00030 class Dir : public DirHandle {
00031 public:
00032     /** Create an uninitialized directory
00033      *
00034      *  Must call open to initialize the directory on a file system
00035      */
00036     Dir();
00037 
00038     /** Open a directory on a filesystem 
00039      *
00040      *  @param fs       Filesystem as target for a directory
00041      *  @param path     Name of the directory to open
00042      */
00043     Dir(FileSystem *fs, const char *path);
00044 
00045     /** Destroy a file
00046      *
00047      *  Closes file if the file is still open
00048      */
00049     virtual ~Dir();
00050 
00051     /** Open a directory on the filesystem
00052      *
00053      *  @param fs       Filesystem as target for a directory
00054      *  @param path     Name of the directory to open
00055      *  @return         0 on success, negative error code on failure
00056      */
00057     virtual int open(FileSystem *fs, const char *path);
00058 
00059     /** Close a directory
00060      *
00061      *  return          0 on success, negative error code on failure
00062      */
00063     virtual int close();
00064 
00065     /** Read the next directory entry
00066      *
00067      *  @param path     The buffer to read the null terminated path name in to
00068      *  @param ent      The directory entry to fill out
00069      *  @return         1 on reading a filename, 0 at end of directory, negative error on failure
00070      */
00071     virtual ssize_t read(struct dirent *ent);
00072 
00073     /** Set the current position of the directory
00074      *
00075      *  @param offset   Offset of the location to seek to,
00076      *                  must be a value returned from tell
00077      */
00078     virtual void seek(off_t offset);
00079 
00080     /** Get the current position of the directory
00081      *
00082      *  @return         Position of the directory that can be passed to rewind
00083      */
00084     virtual off_t tell();
00085 
00086     /** Rewind the current position to the beginning of the directory
00087      */
00088     virtual void rewind();
00089 
00090     /** Get the sizeof the directory 
00091      *
00092      *  @return         Number of files in the directory
00093      */
00094     virtual size_t size();
00095 
00096 private:
00097     FileSystem *_fs;
00098     fs_dir_t _dir;
00099 };
00100 
00101 
00102 /** @}*/
00103 } // namespace mbed
00104 
00105 #endif
00106