Re: [Qemu-devel] [PATCH 0/2] Tunnel character device data over VNC (v1)

["Daniel P. Berrange" <berrange@redhat.com>]

If anyone wants to actually try this code out, the following patch is
a quick proof of concept hack against GTK-VNC[1] and enables a single data
stream for device 'serial0' just printing the received data to stdout.

eg, start QEMU with

  ./i386-softmmu/qemu -kernel ~/vmlinuz  -serial file:foo.log -append 'console=ttyS0' -vnc :1

And then start GTK-VNC with

  ./examples/gvncviewer localhost:1

If all goes to plan, gvncviewer should output the kernel boot messages,
and QEMU will be saving them in 'foo.log' as per its config.

Regards,
Daniel

[1] http://git.gnome.org/cgit/gtk-vnc/

diff --git a/src/gvnc.c b/src/gvnc.c
index c3b3163..7cafa0e 100644
--- a/src/gvnc.c
+++ b/src/gvnc.c
@@ -2144,6 +2144,39 @@ static void gvnc_ext_key_event(struct gvnc *gvnc)
 	gvnc->keycode_map = x_keycode_to_pc_keycode_map();
 }
 
+static void gvnc_stream_event(struct gvnc *gvnc, int deleted)
+{
+	int n_name = gvnc_read_u32(gvnc);
+	char *name;
+	if (gvnc->has_error)
+		return;
+	if (n_name > 4096) {
+		gvnc->has_error = TRUE;
+		return;
+	}
+	name = g_new(char, n_name + 1);
+	gvnc_read(gvnc, name, n_name);
+	name[n_name] = '\0';
+
+	fprintf(stderr, "Got stream %s '%s'\n", deleted ? "del" : "add", name);
+
+	if (strcmp(name, "serial0") == 0) {
+		gvnc_write_u8(gvnc, 255);
+		gvnc_write_u8(gvnc, 2);
+		if (deleted) {
+			gvnc_write_u8(gvnc, 1);
+			gvnc_write_u8(gvnc, 1); /* XXX id */
+		} else {
+			gvnc_write_u8(gvnc, 0);
+			gvnc_write_u32(gvnc, strlen(name));
+			gvnc_write(gvnc, name, strlen(name));
+		}
+		gvnc_flush(gvnc);
+	}
+
+	free(name);
+}
+
 static void gvnc_framebuffer_update(struct gvnc *gvnc, int32_t etype,
 				    uint16_t x, uint16_t y,
 				    uint16_t width, uint16_t height)
@@ -2195,6 +2228,10 @@ static void gvnc_framebuffer_update(struct gvnc *gvnc, int32_t etype,
 	case GVNC_ENCODING_EXT_KEY_EVENT:
 		gvnc_ext_key_event(gvnc);
 		break;
+	case GVNC_ENCODING_STREAM_EVENT:
+		fprintf(stderr, "Stream event\n");
+		gvnc_stream_event(gvnc, x);
+		break;
 	default:
 		GVNC_DEBUG("Received an unknown encoding type: %d\n", etype);
 		gvnc->has_error = TRUE;
@@ -2295,6 +2332,58 @@ gboolean gvnc_server_message(struct gvnc *gvnc)
 		gvnc_server_cut_text(gvnc, data, n_text);
 		g_free(data);
 	}	break;
+	case 255: {
+		int subtype;
+		subtype = gvnc_read_u8(gvnc);
+		if (subtype != 2) {
+			GVNC_DEBUG("Unknown aliguori message type %d\n", subtype);
+			gvnc->has_error = TRUE;
+			break;
+		}
+		switch (gvnc_read_u8(gvnc)) {
+		case 0: {
+			int id;
+			int n_name;
+			char *name;
+			id = gvnc_read_u32(gvnc);
+			n_name = gvnc_read_u32(gvnc);
+			if (n_name > 4096) {
+				GVNC_DEBUG("Stream name too long %d", n_name);
+				gvnc->has_error = TRUE;
+				break;
+			}
+			name = g_new(char, n_name + 1);
+			gvnc_read(gvnc, name, n_name);
+			name[n_name] = 0;
+			fprintf(stderr, "Stream on %d %s\n", id, name);
+			g_free(name);
+		}	break;
+
+		case 1: {
+			int id;
+			id = gvnc_read_u32(gvnc);
+			fprintf(stderr, "Stream off %d\n", id);
+		}	break;
+
+		case 2: {
+			int id;
+			int n_data;
+			char *data;
+			id = gvnc_read_u32(gvnc);
+			n_data = gvnc_read_u32(gvnc);
+			if (n_data > 4096) {
+				GVNC_DEBUG("Stream data too long %d", n_data);
+				gvnc->has_error = TRUE;
+				break;
+			}
+			data = g_new(char, n_data + 1);
+			gvnc_read(gvnc, data, n_data);
+			data[n_data] = 0;
+			fprintf(stderr, "%s", data);
+			g_free(data);
+		}	break;
+		}
+	}       break;
 	default:
 		GVNC_DEBUG("Received an unknown message: %u\n", msg);
 		gvnc->has_error = TRUE;
diff --git a/src/gvnc.h b/src/gvnc.h
index f748de0..4c3d214 100644
--- a/src/gvnc.h
+++ b/src/gvnc.h
@@ -117,6 +117,7 @@ typedef enum {
 
 	GVNC_ENCODING_POINTER_CHANGE = -257,
 	GVNC_ENCODING_EXT_KEY_EVENT = -258,
+	GVNC_ENCODING_STREAM_EVENT = -260,
 } gvnc_encoding;
 
 typedef enum {
diff --git a/src/vncdisplay.c b/src/vncdisplay.c
index 6c7b662..da42434 100644
--- a/src/vncdisplay.c
+++ b/src/vncdisplay.c
@@ -1306,6 +1306,7 @@ static void *vnc_coroutine(void *opaque)
 	/* this order is extremely important! */
 	int32_t encodings[] = {	GVNC_ENCODING_TIGHT_JPEG5,
 				GVNC_ENCODING_TIGHT,
+				GVNC_ENCODING_STREAM_EVENT,
 				GVNC_ENCODING_EXT_KEY_EVENT,
 				GVNC_ENCODING_DESKTOP_RESIZE,
                                 GVNC_ENCODING_WMVi,


-- 
|: Red Hat, Engineering, London   -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505  -o-  F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|