[obs] scheduler: serialize cadence controls

Track the LGMP serial for each accepted frame-schedule message and wait
for its acknowledgement before sending another. Preserve pending RESET,
IMMEDIATE, and feedback state after definite enqueue failures.

Use bounded retry polling and request one fresh immediate frame after an
ambiguous pointer-queue fault recovers.

client/src/app.c

@@ -469,7 +469,8 @@ void app_handleButtonPress(int button)
     return;
   }
 
-  if (!core_inputEnabled() || !g_cursor.inView || !g_cursor.viewReq)
+  if (!core_inputEnabled() || g_cursor.exitWait ||
+      !g_cursor.inView || !g_cursor.viewReq)
     return;
 
   if (!purespice_mousePress(button))
@@ -492,7 +493,7 @@ void app_handleButtonRelease(int button)
     return;
   }
 
-  if (!core_inputEnabled())
+  if (!core_inputEnabled() || g_cursor.exitWait)
     return;
 
   if (!purespice_mouseRelease(button))

client/src/core.c

@@ -62,18 +62,21 @@ static int exitPos(double pos, int edge)
 
 static void cancelExit(const char * why)
 {
-  if (!g_cursor.exit)
+  if (!g_cursor.exit && !g_cursor.exitWait)
     return;
 
   MTRACE("exit cancel=%s target=%.3f,%.3f", why,
       g_cursor.exitPos.x, g_cursor.exitPos.y);
-  g_cursor.exit = false;
+  g_cursor.exit      = false;
+  g_cursor.exitWait  = false;
+  g_cursor.exitRetry = false;
+  g_cursor.exitDelta = (struct DoublePoint) { 0 };
 }
 
-static void finishExit(void)
+static bool finishExit(void)
 {
   if (!g_cursor.exit || g_cursor.viewReq)
-    return;
+    return false;
 
   const int x = exitPos(g_cursor.exitPos.x, g_state.dstRect.x);
   const int y = exitPos(g_cursor.exitPos.y, g_state.dstRect.y);
@@ -82,21 +85,27 @@ static void finishExit(void)
   MTRACE("exit warp target=%d,%d projected=%.3f,%.3f inWin=%d",
       x, y, g_cursor.exitPos.x, g_cursor.exitPos.y, g_cursor.inWindow);
 
-  if (x < 0 || x >= g_state.windowW ||
-      y < 0 || y >= g_state.windowH)
+  if (g_cursor.exitWait)
+    g_cursor.viewReq = true;
+  else if (x < 0 || x >= g_state.windowW ||
+           y < 0 || y >= g_state.windowH)
     g_cursor.inWindow = false;
 
   core_warpPointer(x, y, true);
+  return g_cursor.exitWait;
 }
 
-static void startExit(double x, double y)
+static void startExit(double x, double y, bool wait)
 {
-  g_cursor.exit    = true;
-  g_cursor.exitPos = (struct DoublePoint) { x, y };
+  g_cursor.exit      = true;
+  g_cursor.exitWait  = wait;
+  g_cursor.exitRetry = false;
+  g_cursor.exitPos   = (struct DoublePoint) { x, y };
+  g_cursor.exitDelta = (struct DoublePoint) { 0 };
   core_setCursorInView(false);
 }
 
-static bool moveExit(double ex, double ey)
+static struct DoublePoint exitMove(double ex, double ey)
 {
   if (g_cursor.useScale && g_params.scaleMouseInput)
   {
@@ -106,18 +115,115 @@ static bool moveExit(double ex, double ey)
 
   struct DoublePoint move = {.x = ex, .y = ey};
   util_rotatePoint(&move);
-  g_cursor.exitPos.x += move.x;
-  g_cursor.exitPos.y += move.y;
+  return move;
+}
 
-  const bool inside =
-    g_cursor.exitPos.x >= g_state.dstRect.x &&
-    g_cursor.exitPos.x <  g_state.dstRect.x + g_state.dstRect.w &&
-    g_cursor.exitPos.y >= g_state.dstRect.y &&
-    g_cursor.exitPos.y <  g_state.dstRect.y + g_state.dstRect.h;
+static struct Point exitDir(void)
+{
+  return (struct Point) {
+    .x = g_cursor.exitPos.x < g_state.dstRect.x ? -1 :
+      g_cursor.exitPos.x >= g_state.dstRect.x + g_state.dstRect.w ? 1 : 0,
+    .y = g_cursor.exitPos.y < g_state.dstRect.y ? -1 :
+      g_cursor.exitPos.y >= g_state.dstRect.y + g_state.dstRect.h ? 1 : 0,
+  };
+}
 
-  MTRACE("exit move=%.3f,%.3f target=%.3f,%.3f inside=%d",
-      move.x, move.y, g_cursor.exitPos.x, g_cursor.exitPos.y, inside);
-  return inside;
+static bool exitInward(struct DoublePoint move)
+{
+  const struct Point dir = exitDir();
+  return move.x * dir.x < 0 || move.y * dir.y < 0;
+}
+
+static struct DoublePoint exitInput(struct DoublePoint move)
+{
+  double temp;
+  switch((g_state.rotate + g_params.winRotate) % LG_ROTATE_MAX)
+  {
+    case LG_ROTATE_0:
+      break;
+
+    case LG_ROTATE_90:
+      temp   = move.x;
+      move.x = -move.y;
+      move.y = temp;
+      break;
+
+    case LG_ROTATE_180:
+      move.x = -move.x;
+      move.y = -move.y;
+      break;
+
+    case LG_ROTATE_270:
+      temp   = move.x;
+      move.x = move.y;
+      move.y = -temp;
+      break;
+  }
+
+  if (g_cursor.useScale && g_params.scaleMouseInput)
+  {
+    move.x /= g_cursor.scale.x;
+    move.y /= g_cursor.scale.y;
+  }
+
+  return move;
+}
+
+static struct DoublePoint clampExit(double ex, double ey)
+{
+  struct DoublePoint move = exitMove(ex, ey);
+  const struct Point dir = exitDir();
+  if (move.x * dir.x > 0)
+    move.x = 0;
+  if (move.y * dir.y > 0)
+    move.y = 0;
+
+  const struct DoublePoint input = exitInput(move);
+  MTRACE("exit clamp input=%.3f,%.3f move=%.3f,%.3f dir=%d,%d",
+      input.x, input.y, move.x, move.y, dir.x, dir.y);
+  return input;
+}
+
+static bool moveExit(double ex, double ey)
+{
+  const struct DoublePoint move = exitMove(ex, ey);
+  const bool inward = exitInward(move);
+
+  if (!inward)
+  {
+    g_cursor.exitPos.x += move.x;
+    g_cursor.exitPos.y += move.y;
+  }
+
+  MTRACE("exit move=%.3f,%.3f target=%.3f,%.3f inward=%d",
+      move.x, move.y, g_cursor.exitPos.x, g_cursor.exitPos.y, inward);
+  return inward;
+}
+
+static void startRetry(void)
+{
+  if (!g_cursor.exitWait || g_cursor.exit || g_cursor.exitRetry)
+    return;
+
+  MTRACE("exit retry target=%.3f,%.3f", g_cursor.exitPos.x,
+      g_cursor.exitPos.y);
+  g_cursor.pos.x     = util_clamp(g_cursor.exitPos.x, 0,
+      g_state.windowW - 1);
+  g_cursor.pos.y     = util_clamp(g_cursor.exitPos.y, 0,
+      g_state.windowH - 1);
+  g_cursor.exitRetry = true;
+  g_cursor.realign   = true;
+  g_state.ds->grabPointer();
+}
+
+static void retryExit(double ex, double ey)
+{
+  const struct DoublePoint input = clampExit(ex, ey);
+  g_cursor.exitDelta.x += input.x;
+  g_cursor.exitDelta.y += input.y;
+
+  if (input.x != 0 || input.y != 0)
+    startRetry();
 }
 
 bool core_inputEnabled(void)
@@ -193,9 +299,17 @@ void core_setCursorInView(bool enable)
       enable, g_cursor.viewReq, g_cursor.inView, g_state.focused,
       g_cursor.inWindow, g_cursor.grab);
 
-  if (g_cursor.exit &&
-      (enable || !g_state.focused || !g_cursor.inWindow ||
-       g_state.ignoreInput || !g_state.posInfoValid || app_isOverlayMode()))
+  if (enable && g_cursor.exitWait && !g_cursor.exit)
+  {
+    startRetry();
+    return;
+  }
+
+  if ((g_cursor.exit && enable) ||
+      ((g_cursor.exit || g_cursor.exitWait) &&
+       (!g_state.focused || !g_cursor.inWindow || g_state.ignoreInput ||
+        !g_state.posInfoValid || app_isOverlayMode())) ||
+      (g_cursor.exitWait && !g_cursor.exit && !enable))
     cancelExit(enable ? "view" : "state");
 
   if (enable && !g_state.focused)
@@ -253,10 +367,25 @@ void core_handleGrabEvent(bool active)
       warpSupport == LG_DS_WARP_NONE)
     return;
 
+  struct DoublePoint replay = { 0 };
   if (!active)
-    finishExit();
+  {
+    if (finishExit() || g_cursor.exitWait)
+      return;
+  }
+  else if (g_cursor.exitRetry)
+  {
+    replay             = g_cursor.exitDelta;
+    g_cursor.exitWait  = false;
+    g_cursor.exitRetry = false;
+    g_cursor.exitDelta = (struct DoublePoint) { 0 };
+    g_cursor.warpState = WARP_STATE_ON;
+  }
 
   applyView(active, false);
+
+  if (replay.x != 0 || replay.y != 0)
+    core_handleMouseNormal(replay.x, replay.y);
 }
 
 void core_setGrab(bool enable)
@@ -282,6 +411,7 @@ void core_setGrabQuiet(bool enable)
   if (g_cursor.grab == enable)
     return;
 
+  cancelExit("capture");
   g_cursor.grab = enable;
   g_cursor.acc.x = 0.0;
   g_cursor.acc.y = 0.0;
@@ -389,7 +519,10 @@ void core_onWindowSizeChanged(unsigned width, unsigned height)
 
 void core_updatePositionInfo(void)
 {
-  cancelExit("geometry");
+  if (g_cursor.exitWait && !g_cursor.exit)
+    startRetry();
+  else
+    cancelExit("geometry");
 
   if (g_params.setGuestRes &&
       g_state.transportFeatures & LG_TRANSPORT_FEATURE_WINDOW_SIZE)
@@ -630,7 +763,8 @@ void core_handleGuestMouseUpdate(void)
   }
 
   const bool overlay = app_isOverlayMode();
-  if (overlay || !g_cursor.inView || !g_cursor.viewReq)
+  if (overlay || g_cursor.exitWait ||
+      !g_cursor.inView || !g_cursor.viewReq)
   {
     MTRACE("guest drop=%s guest=%d,%d local=%.3f,%.3f inWin=%d "
         "inView=%d req=%d", overlay ? "overlay" : "view",
@@ -712,6 +846,12 @@ void core_handleMouseNormal(double ex, double ey)
   if (!core_inputEnabled())
     return;
 
+  if (g_cursor.exitWait && !g_cursor.exit)
+  {
+    retryExit(ex, ey);
+    return;
+  }
+
   if (g_cursor.viewReq != g_cursor.inView)
   {
     if (g_cursor.viewReq)
@@ -885,7 +1025,9 @@ fallback:
           break;
 
         case LG_DS_WARP_SURFACE:
-          startExit(local.x, local.y);
+          startExit(local.x, local.y,
+              tx < 0 || tx >= g_state.windowW ||
+              ty < 0 || ty >= g_state.windowH);
           return;
 
         case LG_DS_WARP_SCREEN:
@@ -893,7 +1035,7 @@ fallback:
                 g_state.windowPos.x + g_state.border.left + tx,
                 g_state.windowPos.y + g_state.border.top  + ty))
           {
-            startExit(local.x, local.y);
+            startExit(local.x, local.y, false);
             return;
           }
       }

client/src/main.c

@@ -133,6 +133,9 @@ static void lgInit(void)
   g_cursor.inView        = false;
   g_cursor.viewReq       = false;
   g_cursor.exit          = false;
+  g_cursor.exitWait      = false;
+  g_cursor.exitRetry     = false;
+  g_cursor.exitDelta     = (struct DoublePoint) { 0 };
   g_cursor.guest.valid   = false;
 
   // if spice is not in use, hide the local cursor

client/src/main.h

@@ -301,9 +301,18 @@ struct CursorState
   /* true if a pointer exit is waiting for confinement to release */
   bool exit;
 
+  /* true if a surface exit is waiting for a pointer leave */
+  bool exitWait;
+
+  /* true if confinement is being restored after a failed exit */
+  bool exitRetry;
+
   /* the local pointer exit target */
   struct DoublePoint exitPos;
 
+  /* input retained while confinement is restored */
+  struct DoublePoint exitDelta;
+
   /* true if the guest should be realigned to the host when next drawn */
   bool realign;