Code review and fixes.

internal/wine/diagnostics.go

@@ -23,9 +23,10 @@ type helperDiagnostics struct {
 	window     time.Time
 	seen       map[string]bool
 	suppressed atomic.Uint64
-	// onReady, when set before logRecords starts, receives each valid
-	// ready record so the manager can act on it. It runs on the logging
-	// worker and must only record state, never supervise processes.
+	// onReady is installed before the first Write and receives valid ready
+	// records before diagnostic throttling. It runs on the stderr copier
+	// (or finish for a final partial line) and must only publish bounded
+	// state, never log, block, or supervise processes.
 	onReady func(helperReady)
 }
 
@@ -92,6 +93,15 @@ func (output *helperDiagnostics) queueLine(line string) {
 	if !strings.HasPrefix(line, "wine-access: ") {
 		return
 	}
+	// Readiness controls exclusion fallback and must survive a full queue,
+	// diagnostic throttling, and a slow log sink. The line buffer above
+	// bounds parsing independently of how many diagnostics are retained.
+	record := strings.TrimPrefix(line, "wine-access: ")
+	if output.onReady != nil {
+		if ready, valid := parseHelperReady(record); valid {
+			output.onReady(ready)
+		}
+	}
 	now := time.Now()
 	if now.Sub(output.window) >= 10*time.Second {
 		output.window = now
@@ -103,7 +113,7 @@ func (output *helperDiagnostics) queueLine(line string) {
 	}
 	output.seen[line] = true
 	select {
-	case output.lines <- strings.TrimPrefix(line, "wine-access: "):
+	case output.lines <- record:
 	default:
 		output.suppressed.Add(1)
 	}
@@ -136,18 +146,14 @@ func (output *helperDiagnostics) logRecords(logger *slog.Logger) {
 				reportSuppressed()
 				return
 			}
-			if ready, valid := logHelperRecord(logger, line); valid && output.onReady != nil {
-				output.onReady(ready)
-			}
+			logHelperRecord(logger, line)
 		case <-ticker.C:
 			reportSuppressed()
 		}
 	}
 }
 
-// logHelperRecord logs one helper diagnostic line and returns the parsed
-// ready record when the line was a valid one.
-func logHelperRecord(logger *slog.Logger, line string) (helperReady, bool) {
+func logHelperRecord(logger *slog.Logger, line string) {
 	if body, found := strings.CutPrefix(line, "identity "); found {
 		var identity struct {
 			Version  string `json:"version"`
@@ -156,17 +162,17 @@ func logHelperRecord(logger *slog.Logger, line string) (helperReady, bool) {
 		}
 		if err := json.Unmarshal([]byte(body), &identity); err != nil || identity.Version == "" || identity.Revision == "" {
 			logger.Warn("Invalid Wine helper identity record")
-			return helperReady{}, false
+			return
 		}
 		logger.Info("Wine accessibility helper identity", "version", identity.Version,
 			"revision", identity.Revision, "modified", identity.Modified)
-		return helperReady{}, false
+		return
 	}
 	if strings.HasPrefix(line, "ready ") {
 		status, valid := parseHelperReady(line)
 		if !valid {
 			logger.Warn("Invalid Wine helper initialization record")
-			return helperReady{}, false
+			return
 		}
 		logger.Info("Wine accessibility helper initialized", "reader", status.Reader,
 			"controls_enabled", status.ControlsEnabled, "controller", status.Controller,
@@ -174,7 +180,7 @@ func logHelperRecord(logger *slog.Logger, line string) (helperReady, bool) {
 			"win_events", status.WinEvents, "menu_hook", status.MenuHook,
 			"input_hook", status.InputHook, "host32_started", status.Host32Started,
 			"control_poll", status.ControlPoll, "hook_exclusions", status.HookExclusions)
-		return status, true
+		return
 	}
 	// The plain exclusion-count line is expected startup evidence (it is
 	// emitted even when the helper then exits early), while a rejected
@@ -187,7 +193,6 @@ func logHelperRecord(logger *slog.Logger, line string) (helperReady, bool) {
 	} else {
 		logger.Warn("Wine accessibility helper diagnostic", "diagnostic", line)
 	}
-	return helperReady{}, false
 }
 
 func hookExclusionCountLine(line string) bool {