platform_bootable_recovery/ui.h

/*
 * Copyright (C) 2011 The Android Open Source Project
 *
 * 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 RECOVERY_UI_H
#define RECOVERY_UI_H

#include <linux/input.h>
#include <pthread.h>
#include <time.h>

#include <string>

// Abstract class for controlling the user interface during recovery.
class RecoveryUI {
  public:
    RecoveryUI();

    virtual ~RecoveryUI() { }

    // Initialize the object; called before anything else. UI texts will be
    // initialized according to the given locale. Returns true on success.
    virtual bool Init(const std::string& locale);

    // Show a stage indicator.  Call immediately after Init().
    virtual void SetStage(int current, int max) = 0;

    // Set the overall recovery state ("background image").
    enum Icon { NONE, INSTALLING_UPDATE, ERASING, NO_COMMAND, ERROR };
    virtual void SetBackground(Icon icon) = 0;
    virtual void SetSystemUpdateText(bool security_update) = 0;

    // --- progress indicator ---
    enum ProgressType { EMPTY, INDETERMINATE, DETERMINATE };
    virtual void SetProgressType(ProgressType determinate) = 0;

    // Show a progress bar and define the scope of the next operation:
    //   portion - fraction of the progress bar the next operation will use
    //   seconds - expected time interval (progress bar moves at this minimum rate)
    virtual void ShowProgress(float portion, float seconds) = 0;

    // Set progress bar position (0.0 - 1.0 within the scope defined
    // by the last call to ShowProgress).
    virtual void SetProgress(float fraction) = 0;

    // --- text log ---

    virtual void ShowText(bool visible) = 0;

    virtual bool IsTextVisible() = 0;

    virtual bool WasTextEverVisible() = 0;

    // Write a message to the on-screen log (shown if the user has
    // toggled on the text display). Print() will also dump the message
    // to stdout / log file, while PrintOnScreenOnly() not.
    virtual void Print(const char* fmt, ...) __printflike(2, 3) = 0;
    virtual void PrintOnScreenOnly(const char* fmt, ...) __printflike(2, 3) = 0;

    virtual void ShowFile(const char* filename) = 0;

    // --- key handling ---

    // Wait for a key and return it.  May return -1 after timeout.
    virtual int WaitKey();

    virtual bool IsKeyPressed(int key);
    virtual bool IsLongPress();

    // Returns true if you have the volume up/down and power trio typical
    // of phones and tablets, false otherwise.
    virtual bool HasThreeButtons();

    // Erase any queued-up keys.
    virtual void FlushKeys();

    // Called on each key press, even while operations are in progress.
    // Return value indicates whether an immediate operation should be
    // triggered (toggling the display, rebooting the device), or if
    // the key should be enqueued for use by the main thread.
    enum KeyAction { ENQUEUE, TOGGLE, REBOOT, IGNORE };
    virtual KeyAction CheckKey(int key, bool is_long_press);

    // Called when a key is held down long enough to have been a
    // long-press (but before the key is released).  This means that
    // if the key is eventually registered (released without any other
    // keys being pressed in the meantime), CheckKey will be called with
    // 'is_long_press' true.
    virtual void KeyLongPress(int key);

    // Normally in recovery there's a key sequence that triggers
    // immediate reboot of the device, regardless of what recovery is
    // doing (with the default CheckKey implementation, it's pressing
    // the power button 7 times in row).  Call this to enable or
    // disable that feature.  It is enabled by default.
    virtual void SetEnableReboot(bool enabled);

    // --- menu display ---

    // Display some header text followed by a menu of items, which appears
    // at the top of the screen (in place of any scrolling ui_print()
    // output, if necessary).
    virtual void StartMenu(const char* const * headers, const char* const * items,
                           int initial_selection) = 0;

    // Set the menu highlight to the given index, wrapping if necessary.
    // Returns the actual item selected.
    virtual int SelectMenu(int sel) = 0;

    // End menu mode, resetting the text overlay so that ui_print()
    // statements will be displayed.
    virtual void EndMenu() = 0;

  protected:
    void EnqueueKey(int key_code);

    // The locale that's used to show the rendered texts.
    std::string locale_;
    bool rtl_locale_;

    // The normal and dimmed brightness percentages (default: 50 and 25, which means 50% and 25%
    // of the max_brightness). Because the absolute values may vary across devices. These two
    // values can be configured via subclassing. Setting brightness_normal_ to 0 to disable
    // screensaver.
    unsigned int brightness_normal_;
    unsigned int brightness_dimmed_;

  private:
    // Key event input queue
    pthread_mutex_t key_queue_mutex;
    pthread_cond_t key_queue_cond;
    int key_queue[256], key_queue_len;
    char key_pressed[KEY_MAX + 1];     // under key_queue_mutex
    int key_last_down;                 // under key_queue_mutex
    bool key_long_press;               // under key_queue_mutex
    int key_down_count;                // under key_queue_mutex
    bool enable_reboot;                // under key_queue_mutex
    int rel_sum;

    int consecutive_power_keys;
    int last_key;

    bool has_power_key;
    bool has_up_key;
    bool has_down_key;

    struct key_timer_t {
        RecoveryUI* ui;
        int key_code;
        int count;
    };

    pthread_t input_thread_;

    void OnKeyDetected(int key_code);
    int OnInputEvent(int fd, uint32_t epevents);
    void ProcessKey(int key_code, int updown);

    bool IsUsbConnected();

    static void* time_key_helper(void* cookie);
    void time_key(int key_code, int count);

    void SetLocale(const std::string&);

    enum class ScreensaverState { DISABLED, NORMAL, DIMMED, OFF };
    ScreensaverState screensaver_state_;
    // The following two contain the absolute values computed from brightness_normal_ and
    // brightness_dimmed_ respectively.
    unsigned int brightness_normal_value_;
    unsigned int brightness_dimmed_value_;
    bool InitScreensaver();
};

#endif  // RECOVERY_UI_H