WebFileSystem.h

/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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#ifndef WebFileSystem_h
#define WebFileSystem_h

#include "WebCommon.h"
#include "WebFileSystemType.h"
#include "WebURL.h"

namespace WebKit {

// FIXME: Move these classes into platform.
class WebFileSystemCallbacks;
class WebFileWriter;
class WebFileWriterClient;

class WebFileSystem {
public:
    enum Type {
        TypeTemporary,
        TypePersistent,

        // Indicates an isolated filesystem which only exposes a set of files.
        TypeIsolated,

        // Indicates a non-sandboxed filesystem.
        TypeExternal,
    };

    // Moves a file or directory at |srcPath| to |destPath|.
    // WebFileSystemCallbacks::didSucceed() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void move(const WebURL& srcPath, const WebURL& destPath, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Copies a file or directory at |srcPath| to |destPath|.
    // WebFileSystemCallbacks::didSucceed() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void copy(const WebURL& srcPath, const WebURL& destPath, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Deletes a file or directory at a given |path|.
    // It is an error to try to remove a directory that is not empty.
    // WebFileSystemCallbacks::didSucceed() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void remove(const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Deletes a file or directory recursively at a given |path|.
    // WebFileSystemCallbacks::didSucceed() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void removeRecursively(const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Retrieves the metadata information of the file or directory at the given |path|.
    // This may not always return the local platform path in remote filesystem cases.
    // WebFileSystemCallbacks::didReadMetadata() must be called with a valid metadata when the retrieval is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void readMetadata(const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Creates a file at given |path|.
    // If the |path| doesn't exist, it creates a new file at |path|.
    // If |exclusive| is true, it fails if the |path| already exists.
    // If |exclusive| is false, it succeeds if the |path| already exists or
    // it has successfully created a new file at |path|.
    //
    // WebFileSystemCallbacks::didSucceed() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void createFile(const WebURL& path, bool exclusive, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Creates a directory at a given |path|.
    // If the |path| doesn't exist, it creates a new directory at |path|.
    // If |exclusive| is true, it fails if the |path| already exists.
    // If |exclusive| is false, it succeeds if the |path| already exists or it has successfully created a new directory at |path|.
    //
    // WebFileSystemCallbacks::didSucceed() must be called when
    // the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void createDirectory(const WebURL& path, bool exclusive, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Checks if a file exists at a given |path|.
    // WebFileSystemCallbacks::didSucceed() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void fileExists(const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Checks if a directory exists at a given |path|.
    // WebFileSystemCallbacks::didSucceed() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void directoryExists(const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Reads directory entries of a given directory at |path|.
    // WebFileSystemCallbacks::didReadDirectory() must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void readDirectory(const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Creates a WebFileWriter that can be used to write to the given file.
    // This is a fast, synchronous call, and should not stat the filesystem.
    virtual WebFileWriter* createFileWriter(const WebURL& path, WebFileWriterClient*) { WEBKIT_ASSERT_NOT_REACHED(); return 0; }

    // Creates a snapshot file for a given file specified by |path|. It returns the metadata of the created snapshot file.
    // The returned metadata should include a local platform path to the snapshot image.
    // In local filesystem cases the backend may simply return the metadata of the file itself (as well as readMetadata does), while in
    // remote filesystem case the backend may download the file into a temporary snapshot file and return the metadata of the temporary file.
    // The returned metadata is used to create a File object for the |path|.
    // The snapshot file is supposed to be deleted when the last reference to a WebCore::File referring to it's path is dropped.
    // WebFileSystemCallbacks::didCreateSnapshotFile() with the metadata of the snapshot file must be called when the operation is completed successfully.
    // WebFileSystemCallbacks::didFail() must be called otherwise.
    virtual void createSnapshotFileAndReadMetadata(const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

    // DEPRECATED
    virtual void createSnapshotFileAndReadMetadata(const WebURL& blobURL, const WebURL& path, WebFileSystemCallbacks*) { WEBKIT_ASSERT_NOT_REACHED(); }

protected:
    virtual ~WebFileSystem() { }
};

} // namespace WebKit

#endif