[Spice-devel] [PATCH spice-server 2/3] red-worker: Avoid changing message numbers used by replay utility

[Frediano Ziglio]

These constants are saved into record files so their values should not
be changed in order to be able to use old record files.
Recently 2 different patches has attempted to change these values
without noticing the command above the enumeration.
A runtime error will occur registering duplicate message numbers as
soon as a display is created inside the VM.

Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
---
 server/red-worker.h | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/server/red-worker.h b/server/red-worker.h
index 4f64b729..21a08c7b 100644
--- a/server/red-worker.h
+++ b/server/red-worker.h
@@ -44,16 +44,19 @@ typedef uint32_t RedWorkerMessage;
 
 /* Keep message order, only append new messages!
  * Replay code store enum values into save files.
+ * To avoid missing this rule the constants ever used by replay are
+ * explicitly numbered to cause a runtime error when duplicate values
+ * are inserted into the dispatcher.
  */
 enum {
     RED_WORKER_MESSAGE_NOP,
 
-    RED_WORKER_MESSAGE_UPDATE,
-    RED_WORKER_MESSAGE_WAKEUP,
+    RED_WORKER_MESSAGE_UPDATE = 1, /* replay */
+    RED_WORKER_MESSAGE_WAKEUP = 2, /* replay */
     RED_WORKER_MESSAGE_OOM,
     RED_WORKER_MESSAGE_READY, /* unused */
 
-    RED_WORKER_MESSAGE_DISPLAY_CONNECT,
+    RED_WORKER_MESSAGE_DISPLAY_CONNECT = 5, /* replay */
     RED_WORKER_MESSAGE_DISPLAY_DISCONNECT,
     RED_WORKER_MESSAGE_DISPLAY_MIGRATE,
     RED_WORKER_MESSAGE_START,
@@ -67,9 +70,9 @@ enum {
     RED_WORKER_MESSAGE_ADD_MEMSLOT,
     RED_WORKER_MESSAGE_DEL_MEMSLOT,
     RED_WORKER_MESSAGE_RESET_MEMSLOTS,
-    RED_WORKER_MESSAGE_DESTROY_SURFACES,
-    RED_WORKER_MESSAGE_CREATE_PRIMARY_SURFACE,
-    RED_WORKER_MESSAGE_DESTROY_PRIMARY_SURFACE,
+    RED_WORKER_MESSAGE_DESTROY_SURFACES = 19, /* replay */
+    RED_WORKER_MESSAGE_CREATE_PRIMARY_SURFACE = 20, /* replay */
+    RED_WORKER_MESSAGE_DESTROY_PRIMARY_SURFACE = 21, /* replay */
     RED_WORKER_MESSAGE_RESET_CURSOR,
     RED_WORKER_MESSAGE_RESET_IMAGE_CACHE,
     RED_WORKER_MESSAGE_DESTROY_SURFACE_WAIT,
@@ -78,7 +81,7 @@ enum {
     RED_WORKER_MESSAGE_UPDATE_ASYNC,
     RED_WORKER_MESSAGE_ADD_MEMSLOT_ASYNC,
     RED_WORKER_MESSAGE_DESTROY_SURFACES_ASYNC,
-    RED_WORKER_MESSAGE_CREATE_PRIMARY_SURFACE_ASYNC,
+    RED_WORKER_MESSAGE_CREATE_PRIMARY_SURFACE_ASYNC = 29, /* replay */
     RED_WORKER_MESSAGE_DESTROY_PRIMARY_SURFACE_ASYNC,
     RED_WORKER_MESSAGE_DESTROY_SURFACE_WAIT_ASYNC,
     /* suspend/windows resolution change command */
-- 
2.13.5