FileBase.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 "drivers/FileBase.h"
00017 
00018 namespace mbed {
00019 
00020 FileBase *FileBase::_head = NULL;
00021 SingletonPtr<PlatformMutex>  FileBase::_mutex;
00022 
00023 FileBase::FileBase(const char *name, PathType t) : _next(NULL),
00024                                                    _name(name),
00025                                                    _path_type(t) {
00026     _mutex->lock();
00027     if (name != NULL) {
00028         // put this object at head of the list
00029         _next = _head;
00030         _head = this;
00031     } else {
00032         _next = NULL;
00033     }
00034     _mutex->unlock();
00035 }
00036 
00037 FileBase::~FileBase() {
00038     _mutex->lock();
00039     if (_name != NULL) {
00040         // remove this object from the list
00041         if (_head == this) { // first in the list, so just drop me
00042             _head = _next;
00043         } else {             // find the object before me, then drop me
00044             FileBase *p = _head;
00045             while (p->_next != this) {
00046                 p = p->_next;
00047             }
00048             p->_next = _next;
00049         }
00050     }
00051     _mutex->unlock();
00052 }
00053 
00054 FileBase *FileBase::lookup(const char *name, unsigned int len) {
00055     _mutex->lock();
00056     FileBase *p = _head;
00057     while (p != NULL) {
00058         /* Check that p->_name matches name and is the correct length */
00059         if (p->_name != NULL && std::strncmp(p->_name, name, len) == 0 && std::strlen(p->_name) == len) {
00060             _mutex->unlock();
00061             return p;
00062         }
00063         p = p->_next;
00064     }
00065     _mutex->unlock();
00066     return NULL;
00067 }
00068 
00069 FileBase *FileBase::get(int n) {
00070     _mutex->lock();
00071     FileBase *p = _head;
00072     int m = 0;
00073     while (p != NULL) {
00074         if (m == n) {
00075             _mutex->unlock();
00076             return p;
00077         }
00078 
00079         m++;
00080         p = p->_next;
00081     }
00082     _mutex->unlock();
00083     return NULL;
00084 }
00085 
00086 const char* FileBase::getName(void) {
00087     // Constant read so no lock needed
00088     return _name;
00089 }
00090 
00091 PathType FileBase::getPathType(void) {
00092     // Constant read so no lock needed
00093     return _path_type;
00094 }
00095 
00096 } // namespace mbed
00097