vnc.c

qemu性能直逼VMware的仿真器QEMU 的模擬速度約為實機的 25％；約為 Bochs 的 60 倍。Plex86、User-Mode-Linux、VMware 和 Virtual PC 則比

	for (y = 0; y < vs->height; y++) {
	    if (vnc_and_bits(vs->dirty_row[y], width_mask, VNC_DIRTY_WORDS)) {
		int x;
		char *ptr, *old_ptr;

		ptr = row;
		old_ptr = old_row;

		for (x = 0; x < vs->ds->width; x += 16) {
		    if (memcmp(old_ptr, ptr, 16 * vs->depth) == 0) {
			vnc_clear_bit(vs->dirty_row[y], (x / 16));
		    } else {
			has_dirty = 1;
			memcpy(old_ptr, ptr, 16 * vs->depth);
		    }

		    ptr += 16 * vs->depth;
		    old_ptr += 16 * vs->depth;
		}
	    }

	    row += vs->ds->linesize;
	    old_row += vs->ds->linesize;
	}

	if (!has_dirty) {
	    qemu_mod_timer(vs->timer, qemu_get_clock(rt_clock) + VNC_REFRESH_INTERVAL);
	    return;
	}

	/* Count rectangles */
	n_rectangles = 0;
	vnc_write_u8(vs, 0);  /* msg id */
	vnc_write_u8(vs, 0);
	saved_offset = vs->output.offset;
	vnc_write_u16(vs, 0);

	for (y = 0; y < vs->height; y++) {
	    int x;
	    int last_x = -1;
	    for (x = 0; x < vs->width / 16; x++) {
		if (vnc_get_bit(vs->dirty_row[y], x)) {
		    if (last_x == -1) {
			last_x = x;
		    }
		    vnc_clear_bit(vs->dirty_row[y], x);
		} else {
		    if (last_x != -1) {
			int h = find_dirty_height(vs, y, last_x, x);
			send_framebuffer_update(vs, last_x * 16, y, (x - last_x) * 16, h);
			n_rectangles++;
		    }
		    last_x = -1;
		}
	    }
	    if (last_x != -1) {
		int h = find_dirty_height(vs, y, last_x, x);
		send_framebuffer_update(vs, last_x * 16, y, (x - last_x) * 16, h);
		n_rectangles++;
	    }
	}
	vs->output.buffer[saved_offset] = (n_rectangles >> 8) & 0xFF;
	vs->output.buffer[saved_offset + 1] = n_rectangles & 0xFF;
	vnc_flush(vs);

    }
    qemu_mod_timer(vs->timer, qemu_get_clock(rt_clock) + VNC_REFRESH_INTERVAL);
}

static void vnc_timer_init(VncState *vs)
{
    if (vs->timer == NULL) {
	vs->timer = qemu_new_timer(rt_clock, vnc_update_client, vs);
	qemu_mod_timer(vs->timer, qemu_get_clock(rt_clock));
    }
}

static void vnc_dpy_refresh(DisplayState *ds)
{
    VncState *vs = ds->opaque;
    vnc_timer_init(vs);
    vga_hw_update();
}

static int vnc_listen_poll(void *opaque)
{
    VncState *vs = opaque;
    if (vs->csock == -1)
	return 1;
    return 0;
}

static void buffer_reserve(Buffer *buffer, size_t len)
{
    if ((buffer->capacity - buffer->offset) < len) {
	buffer->capacity += (len + 1024);
	buffer->buffer = realloc(buffer->buffer, buffer->capacity);
	if (buffer->buffer == NULL) {
	    fprintf(stderr, "vnc: out of memory\n");
	    exit(1);
	}
    }
}

static int buffer_empty(Buffer *buffer)
{
    return buffer->offset == 0;
}

static char *buffer_end(Buffer *buffer)
{
    return buffer->buffer + buffer->offset;
}

static void buffer_reset(Buffer *buffer)
{
	buffer->offset = 0;
}

static void buffer_append(Buffer *buffer, const void *data, size_t len)
{
    memcpy(buffer->buffer + buffer->offset, data, len);
    buffer->offset += len;
}

static int vnc_client_io_error(VncState *vs, int ret, int last_errno)
{
    if (ret == 0 || ret == -1) {
	if (ret == -1 && (last_errno == EINTR || last_errno == EAGAIN))
	    return 0;

	qemu_set_fd_handler2(vs->csock, NULL, NULL, NULL, NULL);
	closesocket(vs->csock);
	vs->csock = -1;
	buffer_reset(&vs->input);
	buffer_reset(&vs->output);
	vs->need_update = 0;
	return 0;
    }
    return ret;
}

static void vnc_client_error(VncState *vs)
{
    vnc_client_io_error(vs, -1, EINVAL);
}

static void vnc_client_write(void *opaque)
{
    long ret;
    VncState *vs = opaque;

    ret = send(vs->csock, vs->output.buffer, vs->output.offset, 0);
    ret = vnc_client_io_error(vs, ret, socket_error());
    if (!ret)
	return;

    memmove(vs->output.buffer, vs->output.buffer + ret, (vs->output.offset - ret));
    vs->output.offset -= ret;

    if (vs->output.offset == 0) {
	qemu_set_fd_handler2(vs->csock, NULL, vnc_client_read, NULL, vs);
    }
}

static void vnc_read_when(VncState *vs, VncReadEvent *func, size_t expecting)
{
    vs->read_handler = func;
    vs->read_handler_expect = expecting;
}

static void vnc_client_read(void *opaque)
{
    VncState *vs = opaque;
    long ret;

    buffer_reserve(&vs->input, 4096);

    ret = recv(vs->csock, buffer_end(&vs->input), 4096, 0);
    ret = vnc_client_io_error(vs, ret, socket_error());
    if (!ret)
	return;

    vs->input.offset += ret;

    while (vs->read_handler && vs->input.offset >= vs->read_handler_expect) {
	size_t len = vs->read_handler_expect;
	int ret;

	ret = vs->read_handler(vs, vs->input.buffer, len);
	if (vs->csock == -1)
	    return;

	if (!ret) {
	    memmove(vs->input.buffer, vs->input.buffer + len, (vs->input.offset - len));
	    vs->input.offset -= len;
	} else {
	    vs->read_handler_expect = ret;
	}
    }
}

static void vnc_write(VncState *vs, const void *data, size_t len)
{
    buffer_reserve(&vs->output, len);

    if (buffer_empty(&vs->output)) {
	qemu_set_fd_handler2(vs->csock, NULL, vnc_client_read, vnc_client_write, vs);
    }

    buffer_append(&vs->output, data, len);
}

static void vnc_write_s32(VncState *vs, int32_t value)
{
    vnc_write_u32(vs, *(uint32_t *)&value);
}

static void vnc_write_u32(VncState *vs, uint32_t value)
{
    uint8_t buf[4];

    buf[0] = (value >> 24) & 0xFF;
    buf[1] = (value >> 16) & 0xFF;
    buf[2] = (value >>  8) & 0xFF;
    buf[3] = value & 0xFF;

    vnc_write(vs, buf, 4);
}

static void vnc_write_u16(VncState *vs, uint16_t value)
{
    uint8_t buf[2];

    buf[0] = (value >> 8) & 0xFF;
    buf[1] = value & 0xFF;

    vnc_write(vs, buf, 2);
}

static void vnc_write_u8(VncState *vs, uint8_t value)
{
    vnc_write(vs, (char *)&value, 1);
}

static void vnc_flush(VncState *vs)
{
    if (vs->output.offset)
	vnc_client_write(vs);
}

static uint8_t read_u8(uint8_t *data, size_t offset)
{
    return data[offset];
}

static uint16_t read_u16(uint8_t *data, size_t offset)
{
    return ((data[offset] & 0xFF) << 8) | (data[offset + 1] & 0xFF);
}

static int32_t read_s32(uint8_t *data, size_t offset)
{
    return (int32_t)((data[offset] << 24) | (data[offset + 1] << 16) |
		     (data[offset + 2] << 8) | data[offset + 3]);
}

static uint32_t read_u32(uint8_t *data, size_t offset)
{
    return ((data[offset] << 24) | (data[offset + 1] << 16) |
	    (data[offset + 2] << 8) | data[offset + 3]);
}

static void client_cut_text(VncState *vs, size_t len, char *text)
{
}

static void check_pointer_type_change(VncState *vs, int absolute)
{
    if (vs->has_pointer_type_change && vs->absolute != absolute) {
	vnc_write_u8(vs, 0);
	vnc_write_u8(vs, 0);
	vnc_write_u16(vs, 1);
	vnc_framebuffer_update(vs, absolute, 0,
			       vs->ds->width, vs->ds->height, -257);
	vnc_flush(vs);
    }
    vs->absolute = absolute;
}

static void pointer_event(VncState *vs, int button_mask, int x, int y)
{
    int buttons = 0;
    int dz = 0;

    if (button_mask & 0x01)
	buttons |= MOUSE_EVENT_LBUTTON;
    if (button_mask & 0x02)
	buttons |= MOUSE_EVENT_MBUTTON;
    if (button_mask & 0x04)
	buttons |= MOUSE_EVENT_RBUTTON;
    if (button_mask & 0x08)
	dz = -1;
    if (button_mask & 0x10)
	dz = 1;

    if (vs->absolute) {
	kbd_mouse_event(x * 0x7FFF / vs->ds->width,
			y * 0x7FFF / vs->ds->height,
			dz, buttons);
    } else if (vs->has_pointer_type_change) {
	x -= 0x7FFF;
	y -= 0x7FFF;

	kbd_mouse_event(x, y, dz, buttons);
    } else {
	if (vs->last_x != -1)
	    kbd_mouse_event(x - vs->last_x,
			    y - vs->last_y,
			    dz, buttons);
	vs->last_x = x;
	vs->last_y = y;
    }

    check_pointer_type_change(vs, kbd_mouse_is_absolute());
}

static void reset_keys(VncState *vs)
{
    int i;
    for(i = 0; i < 256; i++) {
        if (vs->modifiers_state[i]) {
            if (i & 0x80)
                kbd_put_keycode(0xe0);
            kbd_put_keycode(i | 0x80);
            vs->modifiers_state[i] = 0;
        }
    }
}

static void do_key_event(VncState *vs, int down, uint32_t sym)
{
    int keycode;

    keycode = keysym2scancode(vs->kbd_layout, sym & 0xFFFF);
    
    /* QEMU console switch */
    switch(keycode) {
    case 0x2a:                          /* Left Shift */
    case 0x36:                          /* Right Shift */
    case 0x1d:                          /* Left CTRL */
    case 0x9d:                          /* Right CTRL */
    case 0x38:                          /* Left ALT */
    case 0xb8:                          /* Right ALT */
        if (down)
            vs->modifiers_state[keycode] = 1;
        else
            vs->modifiers_state[keycode] = 0;
        break;
    case 0x02 ... 0x0a: /* '1' to '9' keys */ 
        if (down && vs->modifiers_state[0x1d] && vs->modifiers_state[0x38]) {
            /* Reset the modifiers sent to the current console */
            reset_keys(vs);
            console_select(keycode - 0x02);
            return;
        }
        break;
    }

    if (is_graphic_console()) {
        if (keycode & 0x80)
            kbd_put_keycode(0xe0);
        if (down)
            kbd_put_keycode(keycode & 0x7f);
        else
            kbd_put_keycode(keycode | 0x80);
    } else {
        /* QEMU console emulation */
        if (down) {
            switch (keycode) {
            case 0x2a:                          /* Left Shift */
            case 0x36:                          /* Right Shift */
            case 0x1d:                          /* Left CTRL */
            case 0x9d:                          /* Right CTRL */
            case 0x38:                          /* Left ALT */
            case 0xb8:                          /* Right ALT */
                break;
            case 0xc8:
                kbd_put_keysym(QEMU_KEY_UP);
                break;
            case 0xd0:
                kbd_put_keysym(QEMU_KEY_DOWN);
                break;
            case 0xcb:
                kbd_put_keysym(QEMU_KEY_LEFT);
                break;
            case 0xcd:
                kbd_put_keysym(QEMU_KEY_RIGHT);
                break;
            case 0xd3:
                kbd_put_keysym(QEMU_KEY_DELETE);
                break;
            case 0xc7:
                kbd_put_keysym(QEMU_KEY_HOME);
                break;
            case 0xcf:
                kbd_put_keysym(QEMU_KEY_END);
                break;
            case 0xc9:
                kbd_put_keysym(QEMU_KEY_PAGEUP);
                break;
            case 0xd1:
                kbd_put_keysym(QEMU_KEY_PAGEDOWN);
                break;
            default:
                kbd_put_keysym(sym);
                break;
            }
        }