xemu/ui/xemu.c

/*
 * xemu SDL display driver
 *
 * Copyright (c) 2020 Matt Borgerson
 *
 * Based on sdl2.c, sdl2-gl.c
 *
 * Copyright (c) 2003 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
/* Ported SDL 1.2 code to 2.0 by Dave Airlie. */

#include "qemu/osdep.h"
#include "qemu/module.h"
#include "qemu/thread.h"
#include "qemu/main-loop.h"
#include "qemu-version.h"
#include "ui/console.h"
#include "ui/input.h"
#include "ui/xemu-display.h"
#include "sysemu/runstate.h"
#include "sysemu/sysemu.h"
#include "xemu-hud.h"
#include "xemu-input.h"
#include "xemu-settings.h"
#include "xemu-shaders.h"
#include "hw/xbox/nv2a/gl/gloffscreen.h" // FIXME

// #define DEBUG_XEMU_C

#ifdef DEBUG_XEMU_C
#define DPRINTF(...) fprintf(stderr, __VA_ARGS__)
#else
#define DPRINTF(...)
#endif

void xb_surface_gl_create_texture(DisplaySurface *surface);
void xb_surface_gl_update_texture(DisplaySurface *surface, int x, int y, int w, int h);
void xb_surface_gl_destroy_texture(DisplaySurface *surface);

static void pre_swap(void);
static void post_swap(void);
static void sleep_ns(int64_t ns);

static int sdl2_num_outputs;
static struct sdl2_console *sdl2_console;
static SDL_Surface *guest_sprite_surface;
static int gui_grab; /* if true, all keyboard/mouse events are grabbed */
static int gui_saved_grab;
static int gui_fullscreen;
static int gui_grab_code = KMOD_LALT | KMOD_LCTRL;
static SDL_Cursor *sdl_cursor_normal;
static SDL_Cursor *sdl_cursor_hidden;
static int absolute_enabled;
static int guest_cursor;
static int guest_x, guest_y;
static SDL_Cursor *guest_sprite;
static Notifier mouse_mode_notifier;
static SDL_Window *m_window;
static SDL_GLContext m_context;
int scaling_mode = 1;
struct decal_shader *blit;

static QemuSemaphore display_init_sem;

static void toggle_full_screen(struct sdl2_console *scon);

int xemu_is_fullscreen(void)
{
    return gui_fullscreen;
}

void xemu_toggle_fullscreen(void)
{
    toggle_full_screen(&sdl2_console[0]);
}

#define SDL2_REFRESH_INTERVAL_BUSY 16
#define SDL2_MAX_IDLE_COUNT (2 * GUI_REFRESH_INTERVAL_DEFAULT \
                             / SDL2_REFRESH_INTERVAL_BUSY + 1)

// static void sdl_update_caption(struct sdl2_console *scon);

static struct sdl2_console *get_scon_from_window(uint32_t window_id)
{
    int i;
    for (i = 0; i < sdl2_num_outputs; i++) {
        if (sdl2_console[i].real_window == SDL_GetWindowFromID(window_id)) {
            return &sdl2_console[i];
        }
    }
    return NULL;
}

#if 0
void sdl2_window_create(struct sdl2_console *scon)
{
    int flags = 0;

    if (!scon->surface) {
        return;
    }
    assert(!scon->real_window);

    if (gui_fullscreen) {
        flags |= SDL_WINDOW_FULLSCREEN_DESKTOP;
    } else {
        flags |= SDL_WINDOW_RESIZABLE;
    }
    if (scon->hidden) {
        flags |= SDL_WINDOW_HIDDEN;
    }

    scon->real_window = SDL_CreateWindow("", SDL_WINDOWPOS_UNDEFINED,
                                         SDL_WINDOWPOS_UNDEFINED,
                                         surface_width(scon->surface),
                                         surface_height(scon->surface),
                                         flags);
    scon->real_renderer = SDL_CreateRenderer(scon->real_window, -1, 0);
    if (scon->opengl) {
        scon->winctx = SDL_GL_GetCurrentContext();
    }
    sdl_update_caption(scon);
}

void sdl2_window_destroy(struct sdl2_console *scon)
{
    if (!scon->real_window) {
        return;
    }

    SDL_DestroyRenderer(scon->real_renderer);
    scon->real_renderer = NULL;
    SDL_DestroyWindow(scon->real_window);
    scon->real_window = NULL;
}
#endif

void sdl2_window_resize(struct sdl2_console *scon)
{
    if (!scon->real_window) {
        return;
    }

    SDL_SetWindowSize(scon->real_window,
                      surface_width(scon->surface),
                      surface_height(scon->surface));
}

static void sdl2_redraw(struct sdl2_console *scon)
{
    if (scon->opengl) {
        sdl2_gl_redraw(scon);
    }
}

static void sdl_update_caption(struct sdl2_console *scon)
{
#if 0
    char win_title[1024];
    char icon_title[1024];
    const char *status = "";

    if (!runstate_is_running()) {
        status = " [Stopped]";
    } else if (gui_grab) {
        if (alt_grab) {
            status = " - Press Ctrl-Alt-Shift-G to exit grab";
        } else if (ctrl_grab) {
            status = " - Press Right-Ctrl-G to exit grab";
        } else {
            status = " - Press Ctrl-Alt-G to exit grab";
        }
    }

    if (qemu_name) {
        snprintf(win_title, sizeof(win_title), "QEMU (%s-%d)%s", qemu_name,
                 scon->idx, status);
        snprintf(icon_title, sizeof(icon_title), "QEMU (%s)", qemu_name);
    } else {
        snprintf(win_title, sizeof(win_title), "QEMU%s", status);
        snprintf(icon_title, sizeof(icon_title), "QEMU");
    }

    if (scon->real_window) {
        SDL_SetWindowTitle(scon->real_window, win_title);
    }
#endif
}

static void sdl_hide_cursor(struct sdl2_console *scon)
{
    if (scon->opts->has_show_cursor && scon->opts->show_cursor) {
        return;
    }

    SDL_ShowCursor(SDL_DISABLE);
    SDL_SetCursor(sdl_cursor_hidden);

    if (!qemu_input_is_absolute()) {
        SDL_SetRelativeMouseMode(SDL_TRUE);
    }
}

static void sdl_show_cursor(struct sdl2_console *scon)
{
    if (scon->opts->has_show_cursor && scon->opts->show_cursor) {
        return;
    }

    if (!qemu_input_is_absolute()) {
        SDL_SetRelativeMouseMode(SDL_FALSE);
    }

    if (guest_cursor &&
        (gui_grab || qemu_input_is_absolute() || absolute_enabled)) {
        SDL_SetCursor(guest_sprite);
    } else {
        SDL_SetCursor(sdl_cursor_normal);
    }

    SDL_ShowCursor(SDL_ENABLE);
}

static void sdl_grab_start(struct sdl2_console *scon)
{
#if 0
    QemuConsole *con = scon ? scon->dcl.con : NULL;

    if (!con || !qemu_console_is_graphic(con)) {
        return;
    }
    /*
     * If the application is not active, do not try to enter grab state. This
     * prevents 'SDL_WM_GrabInput(SDL_GRAB_ON)' from blocking all the
     * application (SDL bug).
     */
    if (!(SDL_GetWindowFlags(scon->real_window) & SDL_WINDOW_INPUT_FOCUS)) {
        return;
    }
    if (guest_cursor) {
        SDL_SetCursor(guest_sprite);
        if (!qemu_input_is_absolute() && !absolute_enabled) {
            SDL_WarpMouseInWindow(scon->real_window, guest_x, guest_y);
        }
    } else {
        sdl_hide_cursor(scon);
    }
    SDL_SetWindowGrab(scon->real_window, SDL_TRUE);
    gui_grab = 1;
    sdl_update_caption(scon);
#endif
}

static void sdl_grab_end(struct sdl2_console *scon)
{
    SDL_SetWindowGrab(scon->real_window, SDL_FALSE);
    gui_grab = 0;
    sdl_show_cursor(scon);
    sdl_update_caption(scon);
}

static void absolute_mouse_grab(struct sdl2_console *scon)
{
    int mouse_x, mouse_y;
    int scr_w, scr_h;
    SDL_GetMouseState(&mouse_x, &mouse_y);
    SDL_GetWindowSize(scon->real_window, &scr_w, &scr_h);
    if (mouse_x > 0 && mouse_x < scr_w - 1 &&
        mouse_y > 0 && mouse_y < scr_h - 1) {
        sdl_grab_start(scon);
    }
}

static void sdl_mouse_mode_change(Notifier *notify, void *data)
{
    if (qemu_input_is_absolute()) {
        if (!absolute_enabled) {
            absolute_enabled = 1;
            SDL_SetRelativeMouseMode(SDL_FALSE);
            absolute_mouse_grab(&sdl2_console[0]);
        }
    } else if (absolute_enabled) {
        if (!gui_fullscreen) {
            sdl_grab_end(&sdl2_console[0]);
        }
        absolute_enabled = 0;
    }
}

static void sdl_send_mouse_event(struct sdl2_console *scon, int dx, int dy,
                                 int x, int y, int state)
{
    static uint32_t bmap[INPUT_BUTTON__MAX] = {
        [INPUT_BUTTON_LEFT]       = SDL_BUTTON(SDL_BUTTON_LEFT),
        [INPUT_BUTTON_MIDDLE]     = SDL_BUTTON(SDL_BUTTON_MIDDLE),
        [INPUT_BUTTON_RIGHT]      = SDL_BUTTON(SDL_BUTTON_RIGHT),
    };
    static uint32_t prev_state;

    if (prev_state != state) {
        qemu_input_update_buttons(scon->dcl.con, bmap, prev_state, state);
        prev_state = state;
    }

    if (qemu_input_is_absolute()) {
        qemu_input_queue_abs(scon->dcl.con, INPUT_AXIS_X,
                             x, 0, surface_width(scon->surface));
        qemu_input_queue_abs(scon->dcl.con, INPUT_AXIS_Y,
                             y, 0, surface_height(scon->surface));
    } else {
        if (guest_cursor) {
            x -= guest_x;
            y -= guest_y;
            guest_x += x;
            guest_y += y;
            dx = x;
            dy = y;
        }
        qemu_input_queue_rel(scon->dcl.con, INPUT_AXIS_X, dx);
        qemu_input_queue_rel(scon->dcl.con, INPUT_AXIS_Y, dy);
    }
    qemu_input_event_sync();
}

static void toggle_full_screen(struct sdl2_console *scon)
{
    gui_fullscreen = !gui_fullscreen;
    if (gui_fullscreen) {
        SDL_SetWindowFullscreen(scon->real_window,
                                SDL_WINDOW_FULLSCREEN_DESKTOP);
        gui_saved_grab = gui_grab;
        sdl_grab_start(scon);
    } else {
        if (!gui_saved_grab) {
            sdl_grab_end(scon);
        }
        SDL_SetWindowFullscreen(scon->real_window, 0);
    }

    // Note: If this gets called while rendering HUD, we will draw twice. Just
    // wait for next refresh.
#if 0
    sdl2_redraw(scon);
#endif
}

static int get_mod_state(void)
{
    SDL_Keymod mod = SDL_GetModState();

    if (alt_grab) {
        return (mod & (gui_grab_code | KMOD_LSHIFT)) ==
            (gui_grab_code | KMOD_LSHIFT);
    } else if (ctrl_grab) {
        return (mod & KMOD_RCTRL) == KMOD_RCTRL;
    } else {
        return (mod & gui_grab_code) == gui_grab_code;
    }
}

static void handle_keydown(SDL_Event *ev)
{
    int win;
    struct sdl2_console *scon = get_scon_from_window(ev->key.windowID);
    int gui_key_modifier_pressed = get_mod_state();
    int gui_keysym = 0;

    if (!scon->ignore_hotkeys && gui_key_modifier_pressed && !ev->key.repeat) {
        switch (ev->key.keysym.scancode) {
        case SDL_SCANCODE_2:
        case SDL_SCANCODE_3:
        case SDL_SCANCODE_4:
        case SDL_SCANCODE_5:
        case SDL_SCANCODE_6:
        case SDL_SCANCODE_7:
        case SDL_SCANCODE_8:
        case SDL_SCANCODE_9:
            if (gui_grab) {
                sdl_grab_end(scon);
            }

            win = ev->key.keysym.scancode - SDL_SCANCODE_1;
            if (win < sdl2_num_outputs) {
                sdl2_console[win].hidden = !sdl2_console[win].hidden;
                if (sdl2_console[win].real_window) {
                    if (sdl2_console[win].hidden) {
                        SDL_HideWindow(sdl2_console[win].real_window);
                    } else {
                        SDL_ShowWindow(sdl2_console[win].real_window);
                    }
                }
                gui_keysym = 1;
            }
            break;
        case SDL_SCANCODE_F:
            toggle_full_screen(scon);
            gui_keysym = 1;
            break;
        case SDL_SCANCODE_G:
            gui_keysym = 1;
            if (!gui_grab) {
                sdl_grab_start(scon);
            } else if (!gui_fullscreen) {
                sdl_grab_end(scon);
            }
            break;
        case SDL_SCANCODE_U:
            sdl2_window_resize(scon);
            gui_keysym = 1;
            break;
        default:
            break;
        }
    }
    if (!gui_keysym) {
        sdl2_process_key(scon, &ev->key);
    }
}

static void handle_keyup(SDL_Event *ev)
{
    struct sdl2_console *scon = get_scon_from_window(ev->key.windowID);

    scon->ignore_hotkeys = false;
    sdl2_process_key(scon, &ev->key);
}

static void handle_textinput(SDL_Event *ev)
{
    struct sdl2_console *scon = get_scon_from_window(ev->text.windowID);
    QemuConsole *con = scon ? scon->dcl.con : NULL;

    if (qemu_console_is_graphic(con)) {
        return;
    }
    kbd_put_string_console(con, ev->text.text, strlen(ev->text.text));
}

static void handle_mousemotion(SDL_Event *ev)
{
    int max_x, max_y;
    struct sdl2_console *scon = get_scon_from_window(ev->motion.windowID);

    if (!scon || !qemu_console_is_graphic(scon->dcl.con)) {
        return;
    }

    if (qemu_input_is_absolute() || absolute_enabled) {
        int scr_w, scr_h;
        SDL_GetWindowSize(scon->real_window, &scr_w, &scr_h);
        max_x = scr_w - 1;
        max_y = scr_h - 1;
        if (gui_grab && !gui_fullscreen
            && (ev->motion.x == 0 || ev->motion.y == 0 ||
                ev->motion.x == max_x || ev->motion.y == max_y)) {
            sdl_grab_end(scon);
        }
        if (!gui_grab &&
            (ev->motion.x > 0 && ev->motion.x < max_x &&
             ev->motion.y > 0 && ev->motion.y < max_y)) {
            sdl_grab_start(scon);
        }
    }
    if (gui_grab || qemu_input_is_absolute() || absolute_enabled) {
        sdl_send_mouse_event(scon, ev->motion.xrel, ev->motion.yrel,
                             ev->motion.x, ev->motion.y, ev->motion.state);
    }
}

static void handle_mousebutton(SDL_Event *ev)
{
    int buttonstate = SDL_GetMouseState(NULL, NULL);
    SDL_MouseButtonEvent *bev;
    struct sdl2_console *scon = get_scon_from_window(ev->button.windowID);

    if (!scon || !qemu_console_is_graphic(scon->dcl.con)) {
        return;
    }

    bev = &ev->button;
    if (!gui_grab && !qemu_input_is_absolute()) {
        if (ev->type == SDL_MOUSEBUTTONUP && bev->button == SDL_BUTTON_LEFT) {
            /* start grabbing all events */
            sdl_grab_start(scon);
        }
    } else {
        if (ev->type == SDL_MOUSEBUTTONDOWN) {
            buttonstate |= SDL_BUTTON(bev->button);
        } else {
            buttonstate &= ~SDL_BUTTON(bev->button);
        }
        sdl_send_mouse_event(scon, 0, 0, bev->x, bev->y, buttonstate);
    }
}

static void handle_mousewheel(SDL_Event *ev)
{
    struct sdl2_console *scon = get_scon_from_window(ev->wheel.windowID);
    SDL_MouseWheelEvent *wev = &ev->wheel;
    InputButton btn;

    if (!scon || !qemu_console_is_graphic(scon->dcl.con)) {
        return;
    }

    if (wev->y > 0) {
        btn = INPUT_BUTTON_WHEEL_UP;
    } else if (wev->y < 0) {
        btn = INPUT_BUTTON_WHEEL_DOWN;
    } else {
        return;
    }

    qemu_input_queue_btn(scon->dcl.con, btn, true);
    qemu_input_event_sync();
    qemu_input_queue_btn(scon->dcl.con, btn, false);
    qemu_input_event_sync();
}

static void handle_windowevent(SDL_Event *ev)
{
    struct sdl2_console *scon = get_scon_from_window(ev->window.windowID);
    bool allow_close = true;

    if (!scon) {
        return;
    }

    switch (ev->window.event) {
    case SDL_WINDOWEVENT_RESIZED:
        {
            QemuUIInfo info;
            memset(&info, 0, sizeof(info));
            info.width = ev->window.data1;
            info.height = ev->window.data2;
            dpy_set_ui_info(scon->dcl.con, &info);
        }
        sdl2_redraw(scon);
        break;
    case SDL_WINDOWEVENT_EXPOSED:
        sdl2_redraw(scon);
        break;
    case SDL_WINDOWEVENT_FOCUS_GAINED:
    case SDL_WINDOWEVENT_ENTER:
        if (!gui_grab && (qemu_input_is_absolute() || absolute_enabled)) {
            absolute_mouse_grab(scon);
        }
        /* If a new console window opened using a hotkey receives the
         * focus, SDL sends another KEYDOWN event to the new window,
         * closing the console window immediately after.
         *
         * Work around this by ignoring further hotkey events until a
         * key is released.
         */
        scon->ignore_hotkeys = get_mod_state();
        break;
    case SDL_WINDOWEVENT_FOCUS_LOST:
        if (gui_grab && !gui_fullscreen) {
            sdl_grab_end(scon);
        }
        break;
    case SDL_WINDOWEVENT_RESTORED:
        break;
    case SDL_WINDOWEVENT_MINIMIZED:
        break;
    case SDL_WINDOWEVENT_CLOSE:
        if (qemu_console_is_graphic(scon->dcl.con)) {
            if (scon->opts->has_window_close && !scon->opts->window_close) {
                allow_close = false;
            }
            if (allow_close) {
                no_shutdown = 0;
                qemu_system_shutdown_request(SHUTDOWN_CAUSE_HOST_UI);
            }
        } else {
            SDL_HideWindow(scon->real_window);
            scon->hidden = true;
        }
        break;
    case SDL_WINDOWEVENT_SHOWN:
        scon->hidden = false;
        break;
    case SDL_WINDOWEVENT_HIDDEN:
        scon->hidden = true;
        break;
    }
}

void sdl2_poll_events(struct sdl2_console *scon)
{
    SDL_Event ev1, *ev = &ev1;
    bool allow_close = true;

    if (scon->last_vm_running != runstate_is_running()) {
        scon->last_vm_running = runstate_is_running();
        sdl_update_caption(scon);
    }

    while (SDL_PollEvent(ev)) {
        int kbd = 0, mouse = 0;
        xemu_input_process_sdl_events(ev);
        xemu_hud_process_sdl_events(ev);
        xemu_input_update_controllers();
        xemu_hud_should_capture_kbd_mouse(&kbd, &mouse);

        switch (ev->type) {
        case SDL_KEYDOWN:
            if (kbd) break;
            handle_keydown(ev);
            break;
        case SDL_KEYUP:
            if (kbd) break;
            handle_keyup(ev);
            break;
        case SDL_TEXTINPUT:
            if (kbd) break;
            handle_textinput(ev);
            break;
        case SDL_QUIT:
            if (scon->opts->has_window_close && !scon->opts->window_close) {
                allow_close = false;
            }
            if (allow_close) {
                no_shutdown = 0;
                qemu_system_shutdown_request(SHUTDOWN_CAUSE_HOST_UI);
            }
            break;
        case SDL_MOUSEMOTION:
            if (mouse) break;
            handle_mousemotion(ev);
            break;
        case SDL_MOUSEBUTTONDOWN:
        case SDL_MOUSEBUTTONUP:
            if (mouse) break;
            handle_mousebutton(ev);
            break;
        case SDL_MOUSEWHEEL:
            if (mouse) break;
            handle_mousewheel(ev);
            break;
        case SDL_WINDOWEVENT:
            handle_windowevent(ev);
            break;
        default:
            break;
        }
    }

    scon->idle_counter = 0;
    scon->dcl.update_interval = 16; // Ignored
}

static void sdl_mouse_warp(DisplayChangeListener *dcl,
                           int x, int y, int on)
{
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);

    if (!qemu_console_is_graphic(scon->dcl.con)) {
        return;
    }

    if (on) {
        if (!guest_cursor) {
            sdl_show_cursor(scon);
        }
        if (gui_grab || qemu_input_is_absolute() || absolute_enabled) {
            SDL_SetCursor(guest_sprite);
            if (!qemu_input_is_absolute() && !absolute_enabled) {
                SDL_WarpMouseInWindow(scon->real_window, x, y);
            }
        }
    } else if (gui_grab) {
        sdl_hide_cursor(scon);
    }
    guest_cursor = on;
    guest_x = x, guest_y = y;
}

static void sdl_mouse_define(DisplayChangeListener *dcl,
                             QEMUCursor *c)
{

    if (guest_sprite) {
        SDL_FreeCursor(guest_sprite);
    }

    if (guest_sprite_surface) {
        SDL_FreeSurface(guest_sprite_surface);
    }

    guest_sprite_surface =
        SDL_CreateRGBSurfaceFrom(c->data, c->width, c->height, 32, c->width * 4,
                                 0xff0000, 0x00ff00, 0xff, 0xff000000);

    if (!guest_sprite_surface) {
        fprintf(stderr, "Failed to make rgb surface from %p\n", c);
        return;
    }
    guest_sprite = SDL_CreateColorCursor(guest_sprite_surface,
                                         c->hot_x, c->hot_y);
    if (!guest_sprite) {
        fprintf(stderr, "Failed to make color cursor from %p\n", c);
        return;
    }
    if (guest_cursor &&
        (gui_grab || qemu_input_is_absolute() || absolute_enabled)) {
        SDL_SetCursor(guest_sprite);
    }
}

#if 0
static void sdl_cleanup(void)
{
    if (guest_sprite) {
        SDL_FreeCursor(guest_sprite);
    }
    SDL_QuitSubSystem(SDL_INIT_VIDEO);
}
#endif

static const DisplayChangeListenerOps dcl_gl_ops = {
    .dpy_name                = "sdl2-gl",
    .dpy_gfx_update          = sdl2_gl_update,
    .dpy_gfx_switch          = sdl2_gl_switch,
    .dpy_gfx_check_format    = console_gl_check_format,
    // .dpy_refresh             = sdl2_gl_refresh,
    .dpy_mouse_set           = sdl_mouse_warp,
    .dpy_cursor_define       = sdl_mouse_define,

    .dpy_gl_ctx_create       = sdl2_gl_create_context,
    .dpy_gl_ctx_destroy      = sdl2_gl_destroy_context,
    .dpy_gl_ctx_make_current = sdl2_gl_make_context_current,
    .dpy_gl_ctx_get_current  = sdl2_gl_get_current_context,
    .dpy_gl_scanout_disable  = sdl2_gl_scanout_disable,
    .dpy_gl_scanout_texture  = sdl2_gl_scanout_texture,
    .dpy_gl_update           = sdl2_gl_scanout_flush,
};

static void sdl2_display_very_early_init(DisplayOptions *o)
{
#ifdef __linux__
    /* on Linux, SDL may use fbcon|directfb|svgalib when run without
     * accessible $DISPLAY to open X11 window.  This is often the case
     * when qemu is run using sudo.  But in this case, and when actually
     * run in X11 environment, SDL fights with X11 for the video card,
     * making current display unavailable, often until reboot.
     * So make x11 the default SDL video driver if this variable is unset.
     * This is a bit hackish but saves us from bigger problem.
     * Maybe it's a good idea to fix this in SDL instead.
     */
    setenv("SDL_VIDEODRIVER", "x11", 0);
#endif

    if (SDL_Init(SDL_INIT_VIDEO)) {
        fprintf(stderr, "Could not initialize SDL(%s) - exiting\n",
                SDL_GetError());
        exit(1);
    }

#ifdef SDL_HINT_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR /* only available since SDL 2.0.8 */
    SDL_SetHint(SDL_HINT_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR, "0");
#endif
    SDL_SetHint(SDL_HINT_GRAB_KEYBOARD, "1");
    SDL_SetHint(SDL_HINT_VIDEO_MINIMIZE_ON_FOCUS_LOSS, "0");

    // Initialize rendering context
    SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 8);
    SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8);
    SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8);
    SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);
    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
    SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
    SDL_GL_SetAttribute(
        SDL_GL_CONTEXT_PROFILE_MASK,
        SDL_GL_CONTEXT_PROFILE_CORE);
    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
    SDL_GL_SetSwapInterval(0);

    // Create main window
    m_window = SDL_CreateWindow(
        "xemu",
        SDL_WINDOWPOS_CENTERED,
        SDL_WINDOWPOS_CENTERED,
        1024, 768,
        SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI);
    if (m_window == NULL) {
        fprintf(stderr, "Failed to create main window\n");
        SDL_Quit();
        exit(1);
    }

    m_context = SDL_GL_CreateContext(m_window);
    assert(m_context != NULL);
    if (m_context == NULL) {
        fprintf(stderr, "%s: Failed to create GL context\n", __func__);
        SDL_DestroyWindow(m_window);
        SDL_Quit();
        exit(1);
    }

    int width, height, channels = 0;
    stbi_set_flip_vertically_on_load(0);
    unsigned char *icon_data = stbi_load("./data/xemu_64x64.png", &width, &height, &channels, 4);
    if (icon_data) {
        SDL_Surface *icon = SDL_CreateRGBSurfaceFrom(icon_data, width, height, 32, width*4,
            0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000);
        if (icon) {
            SDL_SetWindowIcon(m_window, icon);
        }
        // Note: Retaining the memory allocated by stbi_load. It's used in place
        // by the SDL surface.
    }

    // Initialize offscreen rendering context now
    glo_context_create();
    SDL_GL_MakeCurrent(NULL, NULL);

    // FIXME: atexit(sdl_cleanup);
}

static void sdl2_display_early_init(DisplayOptions *o)
{
    assert(o->type == DISPLAY_TYPE_XEMU);
    display_opengl = 1;

    SDL_GL_MakeCurrent(m_window, m_context);
    xemu_hud_init(m_window, m_context);
    blit = create_decal_shader(SHADER_TYPE_BLIT);
}

static void sdl2_display_init(DisplayState *ds, DisplayOptions *o)
{
    uint8_t data = 0;
    int i;
    SDL_SysWMinfo info;

    assert(o->type == DISPLAY_TYPE_XEMU);
    SDL_GL_MakeCurrent(m_window, m_context);

    xemu_input_init();
    xemu_settings_get_enum(XEMU_SETTINGS_DISPLAY_SCALE, &scaling_mode);

    memset(&info, 0, sizeof(info));
    SDL_VERSION(&info.version);

    gui_fullscreen = o->has_full_screen && o->full_screen;

#if 1
    // Explicitly set number of outputs to 1 for a single screen. We don't need
    // multiple for now, but maybe in the future debug stuff can go on a second
    // screen.
    sdl2_num_outputs = 1;
#else
    for (i = 0;; i++) {
        QemuConsole *con = qemu_console_lookup_by_index(i);
        if (!con) {
            break;
        }
    }
    sdl2_num_outputs = i;
    if (sdl2_num_outputs == 0) {
        return;
    }
#endif

    sdl2_console = g_new0(struct sdl2_console, sdl2_num_outputs);
    for (i = 0; i < sdl2_num_outputs; i++) {
        QemuConsole *con = qemu_console_lookup_by_index(i);
        assert(con != NULL);
        if (!qemu_console_is_graphic(con) &&
            qemu_console_get_index(con) != 0) {
            sdl2_console[i].hidden = true;
        }
        sdl2_console[i].idx = i;
        sdl2_console[i].opts = o;
        sdl2_console[i].opengl = 1;
        sdl2_console[i].dcl.ops = &dcl_gl_ops;
        sdl2_console[i].dcl.con = con;
        sdl2_console[i].kbd = qkbd_state_init(con);
        register_displaychangelistener(&sdl2_console[i].dcl);

#if defined(SDL_VIDEO_DRIVER_WINDOWS) || defined(SDL_VIDEO_DRIVER_X11)
        if (SDL_GetWindowWMInfo(sdl2_console[i].real_window, &info)) {
#if defined(SDL_VIDEO_DRIVER_WINDOWS)
            qemu_console_set_window_id(con, (uintptr_t)info.info.win.window);
#elif defined(SDL_VIDEO_DRIVER_X11)
            qemu_console_set_window_id(con, info.info.x11.window);
#endif
        }
#endif
    }

    gui_grab = 0;
    if (gui_fullscreen) {
        sdl_grab_start(0);
    }

    mouse_mode_notifier.notify = sdl_mouse_mode_change;
    qemu_add_mouse_mode_change_notifier(&mouse_mode_notifier);

    sdl_cursor_hidden = SDL_CreateCursor(&data, &data, 8, 1, 0, 0);
    sdl_cursor_normal = SDL_GetCursor();

    /* Tell main thread to go ahead and create the app and enter the run loop */
    SDL_GL_MakeCurrent(NULL, NULL);
    qemu_sem_post(&display_init_sem);
}

static QemuDisplay qemu_display_sdl2 = {
    .type       = DISPLAY_TYPE_XEMU,
    .early_init = sdl2_display_early_init,
    .init       = sdl2_display_init,
};

static void register_sdl1(void)
{
    qemu_display_register(&qemu_display_sdl2);
}

type_init(register_sdl1);

void xb_surface_gl_create_texture(DisplaySurface *surface)
{
    // assert(gls);
    assert(QEMU_IS_ALIGNED(surface_stride(surface), surface_bytes_per_pixel(surface)));

    switch (surface->format) {
    case PIXMAN_BE_b8g8r8x8:
    case PIXMAN_BE_b8g8r8a8:
        surface->glformat = GL_BGRA_EXT;
        surface->gltype = GL_UNSIGNED_BYTE;
        break;
    case PIXMAN_BE_x8r8g8b8:
    case PIXMAN_BE_a8r8g8b8:
        surface->glformat = GL_RGBA;
        surface->gltype = GL_UNSIGNED_BYTE;
        break;
    case PIXMAN_r5g6b5:
        surface->glformat = GL_RGB;
        surface->gltype = GL_UNSIGNED_SHORT_5_6_5;
        break;
    default:
        g_assert_not_reached();
    }

    glGenTextures(1, &surface->texture);
    // glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, surface->texture);
    glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT,
                  surface_stride(surface) / surface_bytes_per_pixel(surface));
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
                 surface_width(surface),
                 surface_height(surface),
                 0, surface->glformat, surface->gltype,
                 surface_data(surface));
    glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT, 0);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
}

void xb_surface_gl_update_texture(DisplaySurface *surface, int x, int y, int w, int h)
{
    uint8_t *data = (void *)surface_data(surface);

    if (surface->texture) {
        glBindTexture(GL_TEXTURE_2D, surface->texture);
        glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT,
                      surface_stride(surface)
                      / surface_bytes_per_pixel(surface));
        glTexSubImage2D(GL_TEXTURE_2D, 0,
                        x, y, w, h,
                        surface->glformat, surface->gltype,
                        data + surface_stride(surface) * y
                        + surface_bytes_per_pixel(surface) * x);
        glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT, 0);
    }
}

void xb_surface_gl_destroy_texture(DisplaySurface *surface)
{
    if (!surface || !surface->texture) {
        return;
    }
    glDeleteTextures(1, &surface->texture);
    surface->texture = 0;
}

#if 0
static void sdl2_set_scanout_mode(struct sdl2_console *scon, bool scanout)
{
    if (scon->scanout_mode == scanout) {
        return;
    }

    scon->scanout_mode = scanout;
    if (!scon->scanout_mode) {
        egl_fb_destroy(&scon->guest_fb);
        if (scon->surface) {
            surface_gl_destroy_texture(scon->surface);
            surface_gl_create_texture(scon->surface);
        }
    }
}
#endif

static void xemu_sdl2_gl_render_surface(struct sdl2_console *scon)
{
    int ww, wh;

    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);
    // sdl2_set_scanout_mode(scon, false);
    SDL_GL_GetDrawableSize(scon->real_window, &ww, &wh);

    // Get texture dimensions
    int tw, th;
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D, scon->surface->texture);
    glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &tw);
    glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &th);

    // Calculate scaling factors
    float scale[2];

    if (scaling_mode == DISPLAY_SCALE_STRETCH) {
        // Stretch to fit
        scale[0] = 1.0;
        scale[1] = 1.0;
    } else if (scaling_mode == DISPLAY_SCALE_CENTER) {
        // Centered
        scale[0] = (float)tw/(float)ww;
        scale[1] = (float)th/(float)wh;
    } else {
        // Scale to fit
        float t_ratio = (float)tw/(float)th;
        float w_ratio = (float)ww/(float)wh;
        if (w_ratio >= t_ratio) {
            scale[0] = t_ratio/w_ratio;
            scale[1] = 1.0;
        } else {
            scale[0] = 1.0;
            scale[1] = w_ratio/t_ratio;
        }
    }

    struct decal_shader *s = blit;
    s->flip = 1;

    glViewport(0, 0, ww, wh);
    glUseProgram(s->prog);
    glBindVertexArray(s->vao);
    glUniform1i(s->FlipY_loc, s->flip);
    glUniform4f(s->ScaleOffset_loc, scale[0], scale[1], 0, 0);
    glUniform4f(s->TexScaleOffset_loc, 1.0, 1.0, 0, 0);
    glUniform1i(s->tex_loc, 0);

    glClearColor(0, 0, 0, 0);
    glClear(GL_COLOR_BUFFER_BIT);
    glDrawElements(GL_TRIANGLE_FAN, 4, GL_UNSIGNED_INT, NULL);

    // FIXME: Finer locking
    qemu_mutex_lock_iothread();
    xemu_hud_render();
    qemu_mutex_unlock_iothread();

    // xb_surface_gl_render_texture(scon->surface);
    pre_swap();
    SDL_GL_SwapWindow(scon->real_window);
    post_swap();
}

void sdl2_gl_update(DisplayChangeListener *dcl,
                    int x, int y, int w, int h)
{
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
    assert(scon->opengl);
#if 1
    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);
    if (scon->surface) {
        // glDeleteTextures(1, &scon->surface->texture);
        xb_surface_gl_destroy_texture(scon->surface);
        // assert(glGetError() == GL_NO_ERROR);
    }
    xb_surface_gl_create_texture(scon->surface);
#endif
    scon->updates++;
}

void sdl2_gl_switch(DisplayChangeListener *dcl,
                    DisplaySurface *new_surface)
{
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
    DisplaySurface *old_surface = scon->surface;

    assert(scon->opengl);

    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);
    xb_surface_gl_destroy_texture(scon->surface);

    scon->surface = new_surface;

    if (!new_surface) {
        // qemu_gl_fini_shader(scon->gls);
        // scon->gls = NULL;
        // sdl2_window_destroy(scon);
        return;
    }

    if (!scon->real_window) {
        // sdl2_window_create(scon);
        scon->real_window = m_window;
        scon->winctx = m_context;
        SDL_GL_MakeCurrent(scon->real_window, scon->winctx);

        // scon->gls = qemu_gl_init_shader();
    } else if (old_surface &&
               ((surface_width(old_surface)  != surface_width(new_surface)) ||
                (surface_height(old_surface) != surface_height(new_surface)))) {
        // sdl2_window_resize(scon);
    }

    xb_surface_gl_create_texture(scon->surface);
}

float fps = 1.0;

static void update_fps(void)
{
    static int64_t last_update = 0;
    const float r = 0.5;//0.1;
    static float avg = 1.0;
    int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
    float ms = ((float)(now-last_update)/1000000.0);
    last_update = now;
    if (fabs(avg-ms) > 0.25*avg) avg = ms;
    else avg = avg*(1.0-r)+ms*r;
    fps = 1000.0/avg;
}

void sdl2_gl_refresh(DisplayChangeListener *dcl)
{
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
    assert(scon->opengl);

    update_fps();

    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);

    qemu_mutex_lock_iothread();
    graphic_hw_update(dcl->con);

    if (scon->updates && scon->surface) {
        scon->updates = 0;
    }
    sdl2_poll_events(scon);
    qemu_mutex_unlock_iothread();
    xemu_sdl2_gl_render_surface(scon);
}

void sdl2_gl_redraw(struct sdl2_console *scon)
{
    assert(scon->opengl);

    if (scon->scanout_mode) {
        assert(0);
        /* sdl2_gl_scanout_flush actually only care about
         * the first argument. */
        // return sdl2_gl_scanout_flush(&scon->dcl, 0, 0, 0, 0);
    }
    if (scon->surface) {
        // xemu_sdl2_gl_render_surface(scon);
    }
}

QEMUGLContext sdl2_gl_create_context(DisplayChangeListener *dcl,
                                     QEMUGLParams *params)
{
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
    SDL_GLContext ctx;

    assert(0);
    
    assert(scon->opengl);

    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);

    SDL_GL_SetAttribute(SDL_GL_SHARE_WITH_CURRENT_CONTEXT, 1);
    if (scon->opts->gl == DISPLAYGL_MODE_ON ||
        scon->opts->gl == DISPLAYGL_MODE_CORE) {
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,
                            SDL_GL_CONTEXT_PROFILE_CORE);
    } else if (scon->opts->gl == DISPLAYGL_MODE_ES) {
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,
                            SDL_GL_CONTEXT_PROFILE_ES);
    }
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, params->major_ver);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, params->minor_ver);

    ctx = SDL_GL_CreateContext(scon->real_window);

    /* If SDL fail to create a GL context and we use the "on" flag,
     * then try to fallback to GLES.
     */
    if (!ctx && scon->opts->gl == DISPLAYGL_MODE_ON) {
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,
                            SDL_GL_CONTEXT_PROFILE_ES);
        ctx = SDL_GL_CreateContext(scon->real_window);
    }
    return (QEMUGLContext)ctx;
}

void sdl2_gl_destroy_context(DisplayChangeListener *dcl, QEMUGLContext ctx)
{
    SDL_GLContext sdlctx = (SDL_GLContext)ctx;

    SDL_GL_DeleteContext(sdlctx);
}

int sdl2_gl_make_context_current(DisplayChangeListener *dcl,
                                 QEMUGLContext ctx)
{
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
    SDL_GLContext sdlctx = (SDL_GLContext)ctx;

    assert(scon->opengl);

    return SDL_GL_MakeCurrent(scon->real_window, sdlctx);
}

QEMUGLContext sdl2_gl_get_current_context(DisplayChangeListener *dcl)
{
    SDL_GLContext sdlctx;

    sdlctx = SDL_GL_GetCurrentContext();
    return (QEMUGLContext)sdlctx;
}

void sdl2_gl_scanout_disable(DisplayChangeListener *dcl)
{
    assert(0);
#if 0
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);

    assert(scon->opengl);
    scon->w = 0;
    scon->h = 0;
    sdl2_set_scanout_mode(scon, false);
#endif
}

void sdl2_gl_scanout_texture(DisplayChangeListener *dcl,
                             uint32_t backing_id,
                             bool backing_y_0_top,
                             uint32_t backing_width,
                             uint32_t backing_height,
                             uint32_t x, uint32_t y,
                             uint32_t w, uint32_t h)
{
    assert(0);
#if 0 
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);

    assert(scon->opengl);
    scon->x = x;
    scon->y = y;
    scon->w = w;
    scon->h = h;
    scon->y0_top = backing_y_0_top;

    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);

    sdl2_set_scanout_mode(scon, true);
    egl_fb_setup_for_tex(&scon->guest_fb, backing_width, backing_height,
                         backing_id, false);
#endif
}

void sdl2_gl_scanout_flush(DisplayChangeListener *dcl,
                           uint32_t x, uint32_t y, uint32_t w, uint32_t h)
{
    assert(0);
#if 0
    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
    int ww, wh;

    assert(scon->opengl);
    if (!scon->scanout_mode) {
        return;
    }
    if (!scon->guest_fb.framebuffer) {
        return;
    }

    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);

    SDL_GetWindowSize(scon->real_window, &ww, &wh);
    egl_fb_setup_default(&scon->win_fb, ww, wh);
    egl_fb_blit(&scon->win_fb, &scon->guest_fb, !scon->y0_top);

    SDL_GL_SwapWindow(scon->real_window);
#endif
}

// sdl2-input.c
void sdl2_process_key(struct sdl2_console *scon,
                      SDL_KeyboardEvent *ev)
{
    int qcode;
    QemuConsole *con = scon->dcl.con;

    if (ev->keysym.scancode >= qemu_input_map_usb_to_qcode_len) {
        return;
    }
    qcode = qemu_input_map_usb_to_qcode[ev->keysym.scancode];
    qkbd_state_key_event(scon->kbd, qcode, ev->type == SDL_KEYDOWN);

    if (!qemu_console_is_graphic(con)) {
        bool ctrl = qkbd_state_modifier_get(scon->kbd, QKBD_MOD_CTRL);
        if (ev->type == SDL_KEYDOWN) {
            switch (qcode) {
            case Q_KEY_CODE_RET:
                kbd_put_keysym_console(con, '\n');
                break;
            default:
                kbd_put_qcode_console(con, qcode, ctrl);
                break;
            }
        }
    }
}

int gArgc;
char **gArgv;

// vl.c
int qemu_main(int argc, char **argv, char **envp);

static void *call_qemu_main(void *opaque)
{
    int status;

    DPRINTF("Second thread: calling qemu_main()\n");
    status = qemu_main(gArgc, gArgv, NULL);
    DPRINTF("Second thread: qemu_main() returned, exiting\n");
    exit(status);
}

static void pre_swap(void)
{
}

/* Note: only supports millisecond resolution on Windows */
static void sleep_ns(int64_t ns)
{
#ifndef _WIN32
        struct timespec sleep_delay, rem_delay;
        sleep_delay.tv_sec = ns / 1000000000LL;
        sleep_delay.tv_nsec = ns % 1000000000LL;
        nanosleep(&sleep_delay, &rem_delay);
#else
        Sleep(ns / SCALE_MS);
#endif
}

static void post_swap(void)
{
    // Throttle to make sure swaps happen at 60Hz
    static int64_t last_update = 0;
    int64_t deadline = last_update + 16666666;
    int64_t sleep_acc = 0;
    int64_t spin_acc = 0;

#ifndef _WIN32
    const int64_t sleep_threshold = 2000000;
#else
    const int64_t sleep_threshold = 250000;
#endif

    while (1) {
        int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
        int64_t time_remaining = deadline - now;
        if (now < deadline) {
            if (time_remaining > sleep_threshold) {
                // Try to sleep until the until reaching the sleep threshold.
                sleep_ns(time_remaining - sleep_threshold);
                sleep_acc += qemu_clock_get_ns(QEMU_CLOCK_REALTIME)-now;
            } else {
                // Simply spin to avoid extra delays incurred with swapping to
                // another process and back in the event of being within
                // threshold to desired event.
                spin_acc++;
            }
        } else {
            DPRINTF("zzZz %g %ld\n", (double)sleep_acc/1000000.0, spin_acc);
            last_update = now;
            break;
        }
    }
}

int main(int argc, char **argv)
{
    QemuThread thread;

    DPRINTF("Entered main()\n");
    gArgc = argc;
    gArgv = argv;

    sdl2_display_very_early_init(NULL);

    qemu_sem_init(&display_init_sem, 0);
    qemu_thread_create(&thread, "qemu_main", call_qemu_main,
                       NULL, QEMU_THREAD_DETACHED);

    DPRINTF("Main thread: waiting for display_init_sem\n");
    qemu_sem_wait(&display_init_sem);
    DPRINTF("Main thread: initializing app\n");

    while (1) {
        sdl2_gl_refresh(&sdl2_console[0].dcl);
    }
}