FileSystemLike.cpp

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 #include "FileSystemLike.h"
00017 
00018 namespace mbed {
00019 
00020 class BaseDirHandle : public DirHandle {
00021 public:
00022     /*
00023       We keep track of our current location as the n'th object in the
00024       FileSystemLike list. Using a Base* instead would cause problems if that
00025       object were to be destroyed between readdirs.
00026       Using this method does mean though that destroying/creating objects can
00027       give unusual results from readdir.
00028     */
00029     off_t n;
00030     struct dirent cur_entry;
00031 
00032     BaseDirHandle() : n(0), cur_entry() {
00033     }
00034 
00035     virtual int closedir() {
00036         delete this;
00037         return 0;
00038     }
00039 
00040     virtual struct dirent *readdir() {
00041         FileBase *ptr = FileBase::get(n);
00042         if (ptr == NULL) return NULL;
00043 
00044         /* Increment n, so next readdir gets the next item */
00045         n++;
00046 
00047         /* Setup cur entry and return a pointer to it */
00048         std::strncpy(cur_entry.d_name, ptr->getName(), NAME_MAX);
00049         return &cur_entry;
00050     }
00051 
00052     virtual off_t telldir() {
00053         return n;
00054     }
00055 
00056     virtual void seekdir(off_t offset) {
00057         n = offset;
00058     }
00059 
00060     virtual void rewinddir() {
00061         n = 0;
00062     }
00063 };
00064 
00065 FileSystemLike::FileSystemLike(const char *name) : FileBase(name, FileSystemPathType) {
00066 
00067 }
00068 
00069 FileSystemLike::~FileSystemLike() {
00070 
00071 }
00072 
00073 DirHandle *FileSystemLike::opendir() {
00074     return new BaseDirHandle();
00075 }
00076 
00077 } // namespace mbed