mbed-os/drivers/DirHandle.h

125 lines
3.1 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.
*/
#ifndef MBED_DIRHANDLE_H
#define MBED_DIRHANDLE_H
#if defined(__ARMCC_VERSION) || defined(__ICCARM__)
# define NAME_MAX 255
typedef int mode_t;
#else
# include <sys/syslimits.h>
#endif
#include "FileHandle.h"
struct dirent {
char d_name[NAME_MAX+1];
};
namespace mbed {
/** \addtogroup drivers */
/** @{*/
/** Represents a directory stream. Objects of this type are returned
* by a FileSystemLike's opendir method. Implementations must define
* at least closedir, readdir and rewinddir.
*
* If a FileSystemLike class defines the opendir method, then the
* directories of an object of that type can be accessed by
* DIR *d = opendir("/example/directory") (or opendir("/example")
* to open the root of the filesystem), and then using readdir(d) etc.
*
* The root directory is considered to contain all FileLike and
* FileSystemLike objects, so the DIR* returned by opendir("/") will
* reflect this.
*
* @Note Synchronization level: Set by subclass
*/
class DirHandle {
public:
/** Closes the directory.
*
* @returns
* 0 on success,
* -1 on error.
*/
virtual int closedir()=0;
/** Return the directory entry at the current position, and
* advances the position to the next entry.
*
* @returns
* A pointer to a dirent structure representing the
* directory entry at the current position, or NULL on reaching
* end of directory or error.
*/
virtual struct dirent *readdir()=0;
/** Resets the position to the beginning of the directory.
*/
virtual void rewinddir()=0;
/** Returns the current position of the DirHandle.
*
* @returns
* the current position,
* -1 on error.
*/
virtual off_t telldir() { return -1; }
/** Sets the position of the DirHandle.
*
* @param location The location to seek to. Must be a value returned by telldir.
*/
virtual void seekdir(off_t location) { (void)location;}
virtual ~DirHandle() {}
protected:
/** Acquire exclusive access to this object.
*/
virtual void lock() {
// Stub
}
/** Release exclusive access to this object.
*/
virtual void unlock() {
// Stub
}
};
} // namespace mbed
typedef mbed::DirHandle DIR;
extern "C" {
DIR *opendir(const char*);
struct dirent *readdir(DIR *);
int closedir(DIR*);
void rewinddir(DIR*);
long telldir(DIR*);
void seekdir(DIR*, long);
int mkdir(const char *name, mode_t n);
};
#endif /* MBED_DIRHANDLE_H */
/** @}*/