mbed-os/drivers/FileSystemLike.cpp

102 lines
2.4 KiB
C++

/* mbed Microcontroller Library
* Copyright (c) 2006-2013 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "drivers/FileSystemLike.h"
namespace mbed {
class BaseDirHandle : public DirHandle {
public:
/*
We keep track of our current location as the n'th object in the
FileSystemLike list. Using a Base* instead would cause problems if that
object were to be destroyed between readdirs.
Using this method does mean though that destroying/creating objects can
give unusual results from readdir.
*/
off_t n;
struct dirent cur_entry;
BaseDirHandle() : n(0), cur_entry() {
}
virtual int closedir() {
// No lock can be used in destructor
delete this;
return 0;
}
virtual struct dirent *readdir() {
lock();
FileBase *ptr = FileBase::get(n);
if (ptr == NULL) {
unlock();
return NULL;
}
/* Increment n, so next readdir gets the next item */
n++;
/* Setup cur entry and return a pointer to it */
std::strncpy(cur_entry.d_name, ptr->getName(), NAME_MAX);
unlock();
return &cur_entry;
}
virtual off_t telldir() {
lock();
off_t offset = n;
unlock();
return offset;
}
virtual void seekdir(off_t offset) {
lock();
n = offset;
unlock();
}
virtual void rewinddir() {
lock();
n = 0;
unlock();
}
protected:
PlatformMutex _mutex;
virtual void lock() {
_mutex.lock();
}
virtual void unlock() {
_mutex.unlock();
}
};
FileSystemLike::FileSystemLike(const char *name) : FileBase(name, FileSystemPathType) {
}
FileSystemLike::~FileSystemLike() {
}
DirHandle *FileSystemLike::opendir() {
return new BaseDirHandle();
}
} // namespace mbed