Attempt to make audio and speech discovery more robust.

internal/speech/catalog.go

@@ -4,6 +4,7 @@
 package speech
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"sort"
@@ -45,7 +46,7 @@ func Discover(options Options) (Catalog, error) {
 	if err != nil {
 		return result, err
 	}
-	defer w.conn.Close()
+	defer w.close()
 	deadline := time.Now().Add(4 * time.Second)
 	query := func(command string) ([]string, error) {
 		if time.Now().After(deadline) {
@@ -176,6 +177,12 @@ func Language_voices(voices []Voice, language string) []Voice {
 // Prepare checks membership because SSIP SET may accept unknown synthesis
 // names without verifying them. The resulting client has not spoken anything.
 func Prepare(driver string, options Options) (Transport, error) {
+	return Prepare_context(context.Background(), driver, options)
+}
+
+// Prepare_context bounds discovery and connection setup together.
+func Prepare_context(ctx context.Context, driver string, options Options) (Transport, error) {
+	options.context = ctx
 	if err := Validate_selection(options.Module, options.Language, options.Voice); err != nil {
 		return nil, err
 	}
@@ -185,7 +192,7 @@ func Prepare(driver string, options Options) (Transport, error) {
 	}
 	if d.Voices == nil {
 		if options.Module == "" && options.Language == "" && options.Voice == "" {
-			return Open_driver(driver, options)
+			return Open_driver_context(ctx, driver, options)
 		}
 		return nil, fmt.Errorf("speech driver does not support voice discovery")
 	}
@@ -219,7 +226,7 @@ func Prepare(driver string, options Options) (Transport, error) {
 	if !languageFound || !voiceFound {
 		return nil, fmt.Errorf("speech language or voice is unavailable for module %q", options.Module)
 	}
-	return Open_driver(driver, options)
+	return Open_driver_context(ctx, driver, options)
 }
 
 // A live change queries only its target, so a slow unrelated module cannot
@@ -232,7 +239,7 @@ func discover_voices(options Options) ([]Voice, error) {
 	if err != nil {
 		return nil, err
 	}
-	defer w.conn.Close()
+	defer w.close()
 	if options.Module != "" {
 		if _, err = w.command("SET SELF OUTPUT_MODULE " + options.Module); err != nil {
 			return nil, err