cg-virtual-monitor/vnc-client/src/main.c

#include <SDL2/SDL.h>
#include <rfb/rfbclient.h>
#include <fxlink/devices.h>
#include <fxlink/logging.h>
#include <stdio.h>
#include <signal.h>
#include <assert.h>
#include <stdbool.h>

/* Application globals */
struct app {
    /* RFB/VNC client to get framebuffers from VNC server */
    rfbClient *client;
    /* SDL globals used to store the framebuffer and show it on-screen */
    SDL_Window *window;
    SDL_Surface *surface;
    /* CLI options */
    bool display_calc;
    bool display_sdl;
    /* Calculator tracking */
    libusb_context *libusb_ctx;
    struct fxlink_device *calc;
};
static struct app app = { 0 };

static void cleanup(void)
{
    if(app.client)
        rfbClientCleanup(app.client);
    if(app.window)
        SDL_DestroyWindow(app.window);
    SDL_Quit();
    if(app.calc) {
        fxlink_device_cleanup(app.calc);
        free(app.calc);
    }
    if(app.libusb_ctx)
        libusb_exit(app.libusb_ctx);
}

static void fb_update(rfbClient *client)
{
    if(app.display_sdl) {
        SDL_UpdateWindowSurface(app.window);
    }
    if(app.display_calc && app.calc) {
        uint16_t *fb16 = malloc(396 * 224 * 2);
        uint8_t *buffer = (void *)app.surface->pixels;

        for(int y = 0; y < app.surface->h; y++)
        for(int x = 0; x < app.surface->w; x++) {
            int offset = y * app.surface->pitch + 4 * x;
            int R = buffer[offset + 2];
            int G = buffer[offset + 1];
            int B = buffer[offset + 0];

            /* Conversion to RGB565 */
            int c = ((R & 0xf8) << 8) | ((G & 0xfc) << 3) | ((B & 0xf8) >> 3);
            fb16[396*y + x] = (c >> 8) | (c << 8);
        }

        fxlink_device_start_bulk_OUT(app.calc,
            "cgvm", "fb", fb16, 396*224*2, true);
    }
}

static int get_calculator(void)
{
    int rc;
    if((rc = libusb_init(&app.libusb_ctx)))
        return elog_libusb(rc, "error initializing libusb");

    libusb_set_option(app.libusb_ctx, LIBUSB_OPTION_LOG_LEVEL,
        LIBUSB_LOG_LEVEL_WARNING);
    fxlink_log_grab_libusb_logs();

    delay_t d = delay_infinite();
    app.calc = fxlink_device_find_wait(app.libusb_ctx, NULL, &d);
    if(!app.calc)
        return elog("no calculator found!\n");

    /* Claim the fxlink interface */
    if(!fxlink_device_claim_fxlink(app.calc)) {
        fxlink_device_cleanup(app.calc);
        free(app.calc);
        app.calc = NULL;
        return elog("could not claim fxlink interface on calculator!\n");
    }

    hlog("cgvm");
    log_("connected to %s\n", fxlink_device_id(app.calc));

    fxlink_device_start_bulk_IN(app.calc);
    return 0;
}

static rfbKeySym keycode_to_rfbKeySym(int keycode)
{
    switch(keycode) {
    case 0x91 /* F1     */: return XK_F1;
    case 0x92 /* F2     */: return XK_F2;
    case 0x93 /* F3     */: return XK_F3;
    case 0x94 /* F4     */: return XK_F4;
    case 0x95 /* F5     */: return XK_F5;
    case 0x96 /* F6     */: return XK_F6;

    case 0x81 /* SHIFT  */: return XK_Shift_L;
    case 0x82 /* OPTN   */: return 0;
    case 0x83 /* VARS   */: return XK_Super_L;
    case 0x84 /* MENU   */: return 0;
    case 0x85 /* LEFT   */: return XK_Left;
    case 0x86 /* UP     */: return XK_Up;

    case 0x71 /* ALPHA  */: return XK_Control_L;
    case 0x72 /* SQUARE */: return 0;
    case 0x73 /* POWER  */: return 0;
    case 0x74 /* EXIT   */: return 0;
    case 0x75 /* DOWN   */: return XK_Down;
    case 0x76 /* RIGHT  */: return XK_Right;

    case 0x61 /* XOT    */: return 'a';
    case 0x62 /* LOG    */: return 'b';
    case 0x63 /* LN     */: return 'c';
    case 0x64 /* SIN    */: return 'd';
    case 0x65 /* COS    */: return 'e';
    case 0x66 /* TAN    */: return 'f';

    case 0x51 /* FRAC   */: return 'g';
    case 0x52 /* FD     */: return 'h';
    case 0x53 /* LEFTP  */: return 'i';
    case 0x54 /* RIGHTP */: return 'j';
    case 0x55 /* COMMA  */: return 'k';
    case 0x56 /* ARROW  */: return 'l';

    case 0x41 /* 7      */: return 'm';
    case 0x42 /* 8      */: return 'n';
    case 0x43 /* 9      */: return 'o';
    case 0x44 /* DEL    */: return XK_BackSpace;

    case 0x31 /* 4      */: return 'p';
    case 0x32 /* 5      */: return 'q';
    case 0x33 /* 6      */: return 'r';
    case 0x34 /* MUL    */: return 's';
    case 0x35 /* DIV    */: return 't';

    case 0x21 /* 1      */: return 'u';
    case 0x22 /* 2      */: return 'v';
    case 0x23 /* 3      */: return 'w';
    case 0x24 /* ADD    */: return 'x';
    case 0x25 /* SUB    */: return 'y';

    case 0x11 /* 0      */: return 'z';
    case 0x12 /* DOT    */: return ' ';
    case 0x13 /* EXP    */: return '"';
    case 0x14 /* NEG    */: return '-';
    case 0x15 /* EXE    */: return XK_Return;

    default: return 0;
    }
}


static void handle_calc_message(struct fxlink_message const *msg)
{
    if(fxlink_message_is_apptype(msg, "cgvm", "pressed-keys")) {
        uint8_t *keys = msg->data;
        for(int i = 0; i < msg->size / 2; i++) {
            int code = keycode_to_rfbKeySym(keys[2*i]);
            int down = keys[2*i+1] ? TRUE : FALSE;
            if(code > 0)
                SendKeyEvent(app.client, code, down);
        }
    }
    else {
        hlog("cgvm");
        log_("got unknown message: application '%.16s', type '%.16s'\n",
            msg->application, msg->type);
    }
}

static void usage(int rc)
{
    fprintf(stderr,
        "usage: cgvm_vnc [--calc] [--sdl]\n"
        "Connects to VNC server 127.0.0.1 and gets raw frames.\n"
        "--calc:  Send frames to a calculator (once one is detected).\n"
        "--sdl:   Show frames on an SDL window.\n");
    exit(rc);
}

int main(int argc, char **argv)
{
    for(int i = 1; i < argc; i++) {
        if(!strcmp(argv[i], "-h") || !strcmp(argv[i], "--help"))
            usage(0);
        else if(!strcmp(argv[i], "--calc"))
            app.display_calc = true;
        else if(!strcmp(argv[i], "--sdl"))
            app.display_sdl = true;
        else {
            fprintf(stderr, "error: unrecognized option '%s'\n", argv[i]);
            return 1;
        }
    }
    if(argc == 1)
        usage(0);
    if(!app.display_calc && !app.display_sdl)
        usage(1);

    atexit(cleanup);
    signal(SIGINT, exit);

    /* Create the SDL window regarless of whether display_sdl is set, since we
       use its surface as RFB framebuffer */
    SDL_Init(SDL_INIT_VIDEO);
    app.window = SDL_CreateWindow("CG Virtual Monitor test VNC client",
        SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 396, 224, 0);
    app.surface = SDL_GetWindowSurface(app.window);
    assert(app.surface->format->BytesPerPixel == 4);

    app.client = rfbGetClient(8, 3, 4);
    app.client->FinishedFrameBufferUpdate = fb_update;
    app.client->width = 396;
    app.client->height = 224;
    app.client->frameBuffer = app.surface->pixels;

    app.client->format.bitsPerPixel=32;
    app.client->format.redShift=app.surface->format->Rshift;
    app.client->format.greenShift=app.surface->format->Gshift;
    app.client->format.blueShift=app.surface->format->Bshift;
    app.client->format.redMax=app.surface->format->Rmask>>app.client->format.redShift;
    app.client->format.greenMax=app.surface->format->Gmask>>app.client->format.greenShift;
    app.client->format.blueMax=app.surface->format->Bmask>>app.client->format.blueShift;
    SetFormatAndEncodings(app.client);

    int _argc = 4;
    char *_argv[] = { "cgvm_vnc", "-encodings", "raw", "127.0.0.1", NULL };
    if(!rfbInitClient(app.client, &_argc, _argv)) {
        fprintf(stderr, "rfbInitClient failed\n");
        app.client = NULL;
        return 1;
    }

    if(app.display_calc)
        get_calculator();

    while(1) {
        SDL_Event e;
        while(SDL_PollEvent(&e)) {
            if(e.type == SDL_QUIT) {
                fprintf(stderr, "SDL_QUIT: Exiting...\n");
                exit(0);
            }
        }

        int i = WaitForMessage(app.client, 100);
        if(i < 0) {
            fprintf(stderr, "WaitForMessage() select: %d\n", i);
            continue;
        }
        else if(i > 0 && !HandleRFBServerMessage(app.client)) {
            fprintf(stderr, "HandleRFBServerMessage() failed\n");
            continue;
        }

        /* Run libusb's event loop */
        struct timeval zero_tv = { 0 };
        libusb_handle_events_timeout(app.libusb_ctx, &zero_tv);

        /* Handle incoming transfers from the calc */
        if(app.calc) {
            struct fxlink_message *msg = fxlink_device_finish_bulk_IN(app.calc);
            if(msg) {
                handle_calc_message(msg);
                fxlink_message_free(msg, true);
                fxlink_device_start_bulk_IN(app.calc);
            }
        }
    }
    return 0;
}