tmk_core/tool/mbed/mbed-sdk/libraries/mbed/common/FileSystemLike.cpp

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2006-2013 ARM Limited
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 #include "FileSystemLike.h"
  17
  18 namespace mbed {
  19
  20 class BaseDirHandle : public DirHandle {
  21 public:
  22     /*
  23       We keep track of our current location as the n'th object in the
  24       FileSystemLike list. Using a Base* instead would cause problems if that
  25       object were to be destroyed between readdirs.
  26       Using this method does mean though that destroying/creating objects can
  27       give unusual results from readdir.
  28     */
  29     off_t n;
  30     struct dirent cur_entry;
  31
  32     BaseDirHandle() : n(0), cur_entry() {
  33     }
  34
  35     virtual int closedir() {
  36         delete this;
  37         return 0;
  38     }
  39
  40     virtual struct dirent *readdir() {
  41         FileBase *ptr = FileBase::get(n);
  42         if (ptr == NULL) return NULL;
  43
  44         /* Increment n, so next readdir gets the next item */
  45         n++;
  46
  47         /* Setup cur entry and return a pointer to it */
  48         std::strncpy(cur_entry.d_name, ptr->getName(), NAME_MAX);
  49         return &cur_entry;
  50     }
  51
  52     virtual off_t telldir() {
  53         return n;
  54     }
  55
  56     virtual void seekdir(off_t offset) {
  57         n = offset;
  58     }
  59
  60     virtual void rewinddir() {
  61         n = 0;
  62     }
  63 };
  64
  65 FileSystemLike::FileSystemLike(const char *name) : FileBase(name, FileSystemPathType) {
  66
  67 }
  68
  69 FileSystemLike::~FileSystemLike() {
  70
  71 }
  72
  73 DirHandle *FileSystemLike::opendir() {
  74     return new BaseDirHandle();
  75 }
  76
  77 } // namespace mbed