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