WebCore/platform/AsyncFileSystem.h

/*
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#ifndef AsyncFileSystem_h
#define AsyncFileSystem_h

#if ENABLE(FILE_SYSTEM)

#include "PlatformString.h"
#include <wtf/PassOwnPtr.h>

namespace WebCore {

class AsyncFileSystem;
class AsyncFileSystemCallbacks;

// This class provides async interface for platform-specific DOMFileSystem implementation. Note that all the methods take canonicalized virtual paths.
class AsyncFileSystem : public Noncopyable {
public:
    virtual ~AsyncFileSystem() { }

    // FileSystem type
    enum Type {
        Temporary,
        Persistent,
    };

    virtual void stop() { }
    virtual bool hasPendingActivity() { return false; }

    // Creates and returns a new platform-specific AsyncFileSystem instance if the platform has its own implementation.
    static PassOwnPtr<AsyncFileSystem> create(const String& rootPath);

    // Opens a new file system.
    static void openFileSystem(const String& basePath, const String& storageIdentifier, Type, PassOwnPtr<AsyncFileSystemCallbacks>);

    // Moves a file or directory from srcPath to destPath.
    // AsyncFileSystemCallbacks::didSucceed() is called when the operation is completed successfully.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void move(const String& srcPath, const String& destPath, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Copies a file or directory from srcPath to destPath.
    // AsyncFileSystemCallbacks::didSucceed() is called when the operation is completed successfully.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void copy(const String& srcPath, const String& destPath, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Deletes a file or directory at a given path.
    // AsyncFileSystemCallbacks::didSucceed() is called when the operation is completed successfully.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void remove(const String& path, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Retrieves the metadata information of the file or directory at a given path.
    // AsyncFileSystemCallbacks::didReadMetadata() is called when the operation is completed successfully.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void readMetadata(const String& path, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Creates a file at a given path.  If exclusive flag is true, it fails if the path already exists.
    // AsyncFileSystemCallbacks::didSucceed() is called when the operation is completed successfully.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void createFile(const String& path, bool exclusive, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Creates a directory at a given path.  If exclusive flag is true, it fails if the path already exists.
    // AsyncFileSystemCallbacks::didSucceed() is called when the operation is completed successfully.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void createDirectory(const String& path, bool exclusive, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Checks if a file exists at a given path.
    // AsyncFileSystemCallbacks::didSucceed() is called if the file exists.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void fileExists(const String& path, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Checks if a directory exists at a given path.
    // AsyncFileSystemCallbacks::didSucceed() is called if the directory exists.
    // AsyncFileSystemCallbacks::didFail() is called otherwise.
    virtual void directoryExists(const String& path, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Reads directory entries of a given directory at path.
    // AsyncFileSystemCallbacks::didReadDirectoryEntry() is called when each directory entry is called. AsyncFileSystemCallbacks::didReadDirectoryEntries() is called after a chunk of directory entries have been read.
    // AsyncFileSystemCallbacks::didFail() is when there is an error.
    virtual void readDirectory(const String& path, PassOwnPtr<AsyncFileSystemCallbacks>) = 0;

    // Converts a given absolute virtual path to a platform path that starts with the platform root path of this file system.
    virtual String virtualToPlatformPath(const String& path) const;

protected:
    AsyncFileSystem(const String& platformRootPath)
        : m_platformRootPath(platformRootPath)
    {
    }

    String m_platformRootPath;
};

} // namespace WebCore

#endif // ENABLE(FILE_SYSTEM)

#endif // AsyncFileSystem_h