android-saf-fs.h

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#ifndef ANDROID_SAF_FILESYSTEM_H
#define ANDROID_SAF_FILESYSTEM_H

#include <jni.h>

#include "backends/fs/abstract-fs.h"
#include "common/ptr.h"

#include "backends/fs/android/android-fs.h"

class AndroidSAFFilesystemNode final : public AbstractFSNode, public AndroidFSNode {
protected:
    class GlobalRef final : public Common::SharedPtr<_jobject> {
        struct Deleter {
            void operator()(_jobject *obj);
        };
    public:
        GlobalRef() : Common::SharedPtr<_jobject>() {}
        GlobalRef(const GlobalRef &ref) : Common::SharedPtr<_jobject>(ref) {}
        GlobalRef(JNIEnv *env, jobject jobj) : Common::SharedPtr<_jobject>(jobj ? env->NewGlobalRef(jobj) : nullptr, Deleter()) {
            // Make sure NewGlobalRef succeeded
            assert((jobj == nullptr) == (get() == nullptr));
        }
        GlobalRef &operator=(const GlobalRef &r) {
            Common::SharedPtr<_jobject>::reset(r);
            return *this;
        }

        operator jobject() {
            return Common::SharedPtr<_jobject>::get();
        }
        operator jobject() const {
            return Common::SharedPtr<_jobject>::get();
        }
    };

    class NodeRef final {
    private:
        jlong _ref;

    public:
        NodeRef() : _ref(0) {}
        ~NodeRef() { reset(); }
        NodeRef(const NodeRef &r) { reset(r); }
        NodeRef(JNIEnv *env, jobject node) { reset(env, node); }

        void reset();
        void reset(const NodeRef &r);
        void reset(JNIEnv *env, jobject node);

        NodeRef &operator=(const NodeRef &r) {
            reset(r);
            return *this;
        }

        bool operator==(const NodeRef &r) const {
            return _ref == r._ref;
        }

        bool operator!=(const NodeRef &r) const {
            return _ref != r._ref;
        }

        explicit operator bool() const {
            return _ref != 0;
        }

        jlong get() const { return _ref; }
        jobject localRef(JNIEnv *env) const;
    };

    // SAFFSTree
    static jclass    _CLS_SAFFSTree;

    static jmethodID _MID_addNodeRef;
    static jmethodID _MID_decNodeRef;
    static jmethodID _MID_refToNode;
    static jmethodID _MID_getTreeId;
    static jmethodID _MID_pathToNode;
    static jmethodID _MID_getChildren;
    static jmethodID _MID_getChild;
    static jmethodID _MID_createDirectory;
    static jmethodID _MID_createFile;
    static jmethodID _MID_createReadStream;
    static jmethodID _MID_createWriteStream;
    static jmethodID _MID_removeNode;
    static jmethodID _MID_removeTree;

    static jfieldID _FID__treeName;
    static jfieldID _FID__root;

    // SAFFSNode
    static jmethodID _MID_addRef;

    static jfieldID _FID__parent;
    static jfieldID _FID__path;
    static jfieldID _FID__documentId;
    static jfieldID _FID__flags;

    static bool _JNIinit;

protected:
    static const int DIRECTORY = 1;
    static const int WRITABLE  = 2;
    static const int READABLE  = 4;

    GlobalRef _safTree;
    // When 0, node doesn't exist yet
    // In this case _path is the parent path, _newName the node name and _safParent the parent SAF object
    NodeRef _safNode;

    Common::String _path;
    int _flags;
    NodeRef _safParent;

    // Used when creating a new node
    // Also used for root node to store its pretty name
    Common::String _newName;

public:
    static const char SAF_MOUNT_POINT[];

    static void initJNI();

    static AndroidSAFFilesystemNode *makeFromPath(const Common::String &path);

    static AndroidSAFFilesystemNode *makeFromTree(jobject safTree);

    bool exists() const override { return (bool)_safNode; }
    Common::U32String getDisplayName() const override { return Common::U32String(getName()); }
    Common::String getName() const override;
    Common::String getPath() const override;
    bool isDirectory() const override { return _flags & DIRECTORY; }
    bool isReadable() const override { return _flags & READABLE; }
    bool isWritable() const override { return _flags & WRITABLE; }

    AbstractFSNode *getChild(const Common::String &n) const override;
    bool getChildren(AbstractFSList &list, ListMode mode, bool hidden) const override;
    AbstractFSNode *getParent() const override;

    Common::SeekableReadStream *createReadStream() override;
    Common::SeekableWriteStream *createWriteStream(bool atomic) override;
    bool createDirectory() override;

    bool remove() override;

    void removeTree();
protected:
    AndroidSAFFilesystemNode(const GlobalRef &safTree, jobject safNode);

    AndroidSAFFilesystemNode(const GlobalRef &safTree, jobject safParent,
                             const Common::String &path, const Common::String &name);

    AndroidSAFFilesystemNode(const GlobalRef &safTree, const NodeRef &safParent,
                             const Common::String &path, const Common::String &name);

    void cacheData(JNIEnv *env, jobject node);
};

class AddSAFFakeNode final : public AbstractFSNode, public AndroidFSNode {
protected:
    AbstractFSNode *getChild(const Common::String &name) const override;
    AbstractFSNode *getParent() const override;

public:
    static const char SAF_ADD_FAKE_PATH[];

    AddSAFFakeNode(bool fromPath) : _proxied(nullptr), _fromPath(fromPath) { }
    ~AddSAFFakeNode() override;

    bool exists() const override;

    bool getChildren(AbstractFSList &list, ListMode mode, bool hidden) const override;

    // I18N: This is displayed in the file browser to let the user choose a new folder for Android Storage Attached Framework
    Common::U32String getDisplayName() const override;
    Common::String getName() const override;
    Common::String getPath() const override;

    bool isDirectory() const override { return true; }
    bool isReadable() const override;
    bool isWritable() const override;

    Common::SeekableReadStream *createReadStream() override { return nullptr; }
    Common::SeekableWriteStream *createWriteStream(bool atomic) override { return nullptr; }

    bool createDirectory() override { return false; }
    bool remove() override { return false; }

private:
    void makeProxySAF() const;

    bool _fromPath;
    mutable AbstractFSNode *_proxied;
};
#endif