Move the VT100 input processing logic out of vc_chr_write() into a new
vt100_input() function that operates on QemuVT100 directly, rather than
going through the Chardev/VCChardev layers. This continues the effort
to decouple the VT100 emulation from the chardev backend, making the
VT100 layer self-contained and reusable.

vc_chr_write() becomes a thin wrapper that extracts the QemuVT100 from
the chardev and delegates to vt100_input().

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 ui/console-vc.c | 34 ++++++++++++++++++++--------------
 1 file changed, 20 insertions(+), 14 deletions(-)

diff --git a/ui/console-vc.c b/ui/console-vc.c
index 5cfb3dfcf72..15600128380 100644
--- a/ui/console-vc.c
+++ b/ui/console-vc.c
@@ -1057,29 +1057,35 @@ static void vt100_putchar(QemuVT100 *vt, int ch)
 DECLARE_INSTANCE_CHECKER(VCChardev, VC_CHARDEV,
                          TYPE_CHARDEV_VC)
 
-static int vc_chr_write(Chardev *chr, const uint8_t *buf, int len)
+static size_t vt100_input(QemuVT100 *vt, const uint8_t *buf, size_t len)
 {
-    VCChardev *drv = VC_CHARDEV(chr);
-    QemuTextConsole *s = drv->console;
     int i;
 
-    s->vt.update_x0 = s->vt.width * FONT_WIDTH;
-    s->vt.update_y0 = s->vt.height * FONT_HEIGHT;
-    s->vt.update_x1 = 0;
-    s->vt.update_y1 = 0;
-    vt100_show_cursor(&s->vt, 0);
+    vt->update_x0 = vt->width * FONT_WIDTH;
+    vt->update_y0 = vt->height * FONT_HEIGHT;
+    vt->update_x1 = 0;
+    vt->update_y1 = 0;
+    vt100_show_cursor(vt, 0);
     for(i = 0; i < len; i++) {
-        vt100_putchar(&s->vt, buf[i]);
+        vt100_putchar(vt, buf[i]);
     }
-    vt100_show_cursor(&s->vt, 1);
-    if (s->vt.update_x0 < s->vt.update_x1) {
-        vt100_image_update(&s->vt, s->vt.update_x0, s->vt.update_y0,
-                           s->vt.update_x1 - s->vt.update_x0,
-                           s->vt.update_y1 - s->vt.update_y0);
+    vt100_show_cursor(vt, 1);
+    if (vt->update_x0 < vt->update_x1) {
+        vt100_image_update(vt, vt->update_x0, vt->update_y0,
+                           vt->update_x1 - vt->update_x0,
+                           vt->update_y1 - vt->update_y0);
     }
     return len;
 }
 
+static int vc_chr_write(Chardev *chr, const uint8_t *buf, int len)
+{
+    VCChardev *drv = VC_CHARDEV(chr);
+    QemuTextConsole *s = drv->console;
+
+    return vt100_input(&s->vt, buf, len);
+}
+
 void vt100_update_cursor(void)
 {
     QemuVT100 *vt;

-- 
2.53.0