processor_override: Give input its own message

BUG=b:273232671
TEST=uncomment input.enabled in /etc/cras/processor_override.txtpb

Change-Id: I11aeab35146268f91f2e752522f0e005595a5bd7
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/adhd/+/5020343
Auto-Submit: Li-Yu Yu <aaronyu@google.com>
Reviewed-by: Chih-Yang Hsia <paulhsia@chromium.org>
Commit-Queue: Chih-Yang Hsia <paulhsia@chromium.org>
Tested-by: Li-Yu Yu <aaronyu@google.com>
Tested-by: chromeos-cop-builder@chromeos-cop.iam.gserviceaccount.com <chromeos-cop-builder@chromeos-cop.iam.gserviceaccount.com>

cras-config/processor_override.txtpb

@@ -1,15 +1,19 @@
-# Uncomment the following line to override CRAS processing.
-# enabled: true
+# Input processing override.
+input {
+  # Uncomment the following line to override CRAS input processing.
+  # enabled: true
 
-# Block size of the processor.
-# If 0, use the block size that cras_stream_apm is using.
-block_size: 480
-# Frame rate of the processor.
-# If 0, use the rate that CRAS is using and no resampling is done.
-frame_rate: 48000
+  # Block size of the processor.
+  # If 0, use the block size that cras_stream_apm is using.
+  block_size: 480
+  # Frame rate of the processor.
+  # If 0, use the rate that CRAS is using and no resampling is done.
+  frame_rate: 48000
 
-# The path to the plugin shared library.
-plugin_path: "/usr/local/lib64/libtest_plugins.so"
+  # The path to the plugin shared library.
+  plugin_path: "/usr/local/lib64/libtest_plugins.so"
 
-# The name of the function to create the plugin processor.
-constructor: "abs_processor_create"
+  # The name of the function to create the plugin processor.
+  constructor: "abs_processor_create"
+  # constructor: "plugin_processor_create"
+}

cras/src/server/rust/proto/cras_processor.proto

@@ -1,9 +1,13 @@
 syntax = "proto3";
 
-message CrasProcessorOverride {
+message Plugin {
   bool enabled = 1;
   uint32 block_size = 2;
   uint32 frame_rate = 3;
   string plugin_path = 4;
   string constructor = 5;
 }
+
+message CrasProcessorOverride {
+  Plugin input = 1;
+}

cras/src/server/rust/src/cras_processor.rs

@@ -70,7 +70,7 @@ static GLOBAL_ID_COUNTER: AtomicUsize = AtomicUsize::new(0);
 
 impl CrasProcessor {
     fn new(mut config: CrasProcessorConfig) -> anyhow::Result<Self> {
-        let override_config = processor_override::read_system_config();
+        let override_config = processor_override::read_system_config().input;
         if override_config.enabled {
             config.effect = CrasProcessorEffect::Overridden;
         }
@@ -275,5 +275,5 @@ pub unsafe extern "C" fn cras_processor_create(
 /// Returns true if override is enabled in the system config file.
 #[no_mangle]
 pub extern "C" fn cras_processor_is_override_enabled() -> bool {
-    processor_override::read_system_config().enabled
+    processor_override::read_system_config().input.enabled
 }