console: add qemu_pixman_linebuf_copy

Helper function for copying data from linebuf to framebuffer using
pixman, possibly converting in case src and dst formats differ.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

include/ui/qemu-pixman.h

@@ -42,6 +42,8 @@ pixman_image_t *qemu_pixman_linebuf_create(pixman_format_code_t format,
                                            int width);
 void qemu_pixman_linebuf_fill(pixman_image_t *linebuf, pixman_image_t *fb,
                               int width, int x, int y);
+void qemu_pixman_linebuf_copy(pixman_image_t *fb, int width, int x, int y,
+                              pixman_image_t *linebuf);
 pixman_image_t *qemu_pixman_mirror_create(pixman_format_code_t format,
                                           pixman_image_t *image);
 void qemu_pixman_image_unref(pixman_image_t *image);

ui/qemu-pixman.c

@@ -133,6 +133,7 @@ pixman_image_t *qemu_pixman_linebuf_create(pixman_format_code_t format,
     return image;
 }
 
+/* fill linebuf from framebuffer */
 void qemu_pixman_linebuf_fill(pixman_image_t *linebuf, pixman_image_t *fb,
                               int width, int x, int y)
 {
@@ -140,6 +141,14 @@ void qemu_pixman_linebuf_fill(pixman_image_t *linebuf, pixman_image_t *fb,
                            x, y, 0, 0, 0, 0, width, 1);
 }
 
+/* copy linebuf to framebuffer */
+void qemu_pixman_linebuf_copy(pixman_image_t *fb, int width, int x, int y,
+                              pixman_image_t *linebuf)
+{
+    pixman_image_composite(PIXMAN_OP_SRC, linebuf, NULL, fb,
+                           0, 0, 0, 0, x, y, width, 1);
+}
+
 pixman_image_t *qemu_pixman_mirror_create(pixman_format_code_t format,
                                           pixman_image_t *image)
 {