Diff: mbed-os/features/filesystem/FileSystem.h

Revision:

1:9c5af431a1f1

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os/features/filesystem/FileSystem.h	Tue May 01 15:47:08 2018 +0000
@@ -0,0 +1,268 @@
+
+/* 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_FILESYSTEM_H
+#define MBED_FILESYSTEM_H
+
+#include "platform/platform.h"
+
+#include "platform/FileBase.h"
+#include "platform/FileHandle.h"
+#include "platform/DirHandle.h"
+#include "platform/FileSystemLike.h"
+#include "BlockDevice.h"
+
+namespace mbed {
+/** \addtogroup filesystem */
+/** @{*/
+
+
+// Opaque pointer representing files and directories
+typedef void *fs_file_t;
+typedef void *fs_dir_t;
+
+// Predeclared classes
+class Dir;
+class File;
+
+/** A filesystem object provides filesystem operations and file operations
+ *  for the File and Dir classes on a block device.
+ *
+ *  Implementations must provide at minimum file operations and mount
+ *  operations for block devices.
+ *
+ * @note Synchronization level: Set by subclass
+ */
+class FileSystem : public FileSystemLike {
+public:
+    /** FileSystem lifetime
+     *
+     *  @param name       Name to add filesystem to tree as
+     */
+    FileSystem(const char *name = NULL);
+    virtual ~FileSystem() {}
+
+    /** Mounts a filesystem to a block device
+     *
+     *  @param bd       BlockDevice to mount to
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int mount(BlockDevice *bd) = 0;
+
+    /** Unmounts a filesystem from the underlying block device
+     *
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int unmount() = 0;
+
+    /** Reformats a filesystem, results in an empty and mounted filesystem
+     *
+     *  @param bd       BlockDevice to reformat and mount. If NULL, the mounted
+     *                  block device will be used.
+     *                  Note: if mount fails, bd must be provided.
+     *                  Default: NULL
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int reformat(BlockDevice *bd = NULL);
+
+    /** Remove a file from the filesystem.
+     *
+     *  @param path     The name of the file to remove.
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int remove(const char *path);
+
+    /** Rename a file in the filesystem.
+     *
+     *  @param path     The name of the file to rename.
+     *  @param newpath  The name to rename it to
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int rename(const char *path, const char *newpath);
+
+    /** Store information about the file in a stat structure
+     *
+     *  @param path     The name of the file to find information about
+     *  @param st       The stat buffer to write to
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int stat(const char *path, struct stat *st);
+
+    /** Create a directory in the filesystem.
+     *
+     *  @param path     The name of the directory to create.
+     *  @param mode     The permissions with which to create the directory
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int mkdir(const char *path, mode_t mode);
+
+    /** Store information about the mounted filesystem in a statvfs structure
+     *
+     *  @param path     The name of the file to find information about
+     *  @param buf      The stat buffer to write to
+     *  @return         0 on success, negative error code on failure
+     */
+     virtual int statvfs(const char *path, struct statvfs *buf);
+
+protected:
+    friend class File;
+    friend class Dir;
+
+    /** Open a file on the filesystem
+     *
+     *  @param file     Destination for the handle to a newly created file
+     *  @param path     The name of the file to open
+     *  @param flags    The flags to open the file in, one of O_RDONLY, O_WRONLY, O_RDWR,
+     *                  bitwise or'd with one of O_CREAT, O_TRUNC, O_APPEND
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int file_open(fs_file_t *file, const char *path, int flags) = 0;
+
+    /** Close a file
+     *
+     *  @param file     File handle
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int file_close(fs_file_t file) = 0;
+
+    /** Read the contents of a file into a buffer
+     *
+     *  @param file     File handle
+     *  @param buffer   The buffer to read in to
+     *  @param size     The number of bytes to read
+     *  @return         The number of bytes read, 0 at end of file, negative error on failure
+     */
+    virtual ssize_t file_read(fs_file_t file, void *buffer, size_t size) = 0;
+
+    /** Write the contents of a buffer to a file
+     *
+     *  @param file     File handle
+     *  @param buffer   The buffer to write from
+     *  @param size     The number of bytes to write
+     *  @return         The number of bytes written, negative error on failure
+     */
+    virtual ssize_t file_write(fs_file_t file, const void *buffer, size_t size) = 0;
+
+    /** Flush any buffers associated with the file
+     *
+     *  @param file     File handle
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int file_sync(fs_file_t file);
+
+    /** Check if the file in an interactive terminal device
+     *  If so, line buffered behaviour is used by default
+     *
+     *  @param file     File handle
+     *  @return         True if the file is a terminal
+     */
+    virtual int file_isatty(fs_file_t file);
+
+    /** Move the file position to a given offset from from a given location
+     *
+     *  @param file     File handle
+     *  @param offset   The offset from whence to move to
+     *  @param whence   The start of where to seek
+     *      SEEK_SET to start from beginning of file,
+     *      SEEK_CUR to start from current position in file,
+     *      SEEK_END to start from end of file
+     *  @return         The new offset of the file
+     */
+    virtual off_t file_seek(fs_file_t file, off_t offset, int whence) = 0;
+
+    /** Get the file position of the file
+     *
+     *  @param file     File handle
+     *  @return         The current offset in the file
+     */
+    virtual off_t file_tell(fs_file_t file);
+
+    /** Rewind the file position to the beginning of the file
+     *
+     *  @param file     File handle
+     *  @note This is equivalent to file_seek(file, 0, FS_SEEK_SET)
+     */
+    virtual void file_rewind(fs_file_t file);
+
+    /** Get the size of the file
+     *
+     *  @param file     File handle
+     *  @return         Size of the file in bytes
+     */
+    virtual off_t file_size(fs_file_t file);
+
+    /** Open a directory on the filesystem
+     *
+     *  @param dir      Destination for the handle to the directory
+     *  @param path     Name of the directory to open
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int dir_open(fs_dir_t *dir, const char *path);
+
+    /** Close a directory
+     *
+     *  @param dir      Dir handle
+     *  @return         0 on success, negative error code on failure
+     */
+    virtual int dir_close(fs_dir_t dir);
+
+    /** Read the next directory entry
+     *
+     *  @param dir      Dir handle
+     *  @param ent      The directory entry to fill out
+     *  @return         1 on reading a filename, 0 at end of directory, negative error on failure
+     */
+    virtual ssize_t dir_read(fs_dir_t dir, struct dirent *ent);
+
+    /** Set the current position of the directory
+     *
+     *  @param dir      Dir handle
+     *  @param offset   Offset of the location to seek to,
+     *                  must be a value returned from dir_tell
+     */
+    virtual void dir_seek(fs_dir_t dir, off_t offset);
+
+    /** Get the current position of the directory
+     *
+     *  @param dir      Dir handle
+     *  @return         Position of the directory that can be passed to dir_rewind
+     */
+    virtual off_t dir_tell(fs_dir_t dir);
+
+    /** Rewind the current position to the beginning of the directory
+     *
+     *  @param dir      Dir handle
+     */
+    virtual void dir_rewind(fs_dir_t dir);
+
+    /** Get the sizeof the directory
+     *
+     *  @param dir      Dir handle
+     *  @return         Number of files in the directory
+     */
+    virtual size_t dir_size(fs_dir_t dir);
+
+protected:
+    // Hooks for FileSystemHandle
+    virtual int open(FileHandle **file, const char *path, int flags);
+    virtual int open(DirHandle **dir, const char *path);
+};
+
+
+/** @}*/
+} // namespace mbed
+
+#endif