Implement JNI layer cubeb_fx for controlling android audiofx classes

2 files changed, 185 insertions, 32 deletions

diff --git a/src/cubeb-jni.cpp b/src/cubeb-jni.cpp
index 8e7345b..57c642d 100644
--- a/src/cubeb-jni.cpp
+++ b/src/cubeb-jni.cpp
@@ -1,7 +1,10 @@
 /* clang-format off */
-#include "jni.h"
-#include <assert.h>
+#include "cubeb-jni.h"
 #include "cubeb-jni-instances.h"
+#include <assert.h>
+#include <atomic>
+#include <initializer_list>
+#include <jni.h>
 /* clang-format on */
 
 #define AUDIO_STREAM_TYPE_MUSIC 3
@@ -9,7 +12,53 @@
 struct cubeb_jni {
   jobject s_audio_manager_obj = nullptr;
   jclass s_audio_manager_class = nullptr;
-  jmethodID s_get_output_latency_id = nullptr;
+  jmethodID s_audio_manager_get_output_latency_id = nullptr;
+  struct cubeb_fx_def {
+    jclass clazz = nullptr;
+    jmethodID static_function_is_available = nullptr;
+    jmethodID static_function_create = nullptr;
+    jmethodID method_set_enabled = nullptr;
+    jmethodID method_release = nullptr;
+  } s_fxs[CUBEB_FX_SENTINEL__]{};
+  std::atomic<size_t> cubeb_fx_count{0};
+};
+
+static constexpr const char *
+cubeb_fx_name(cubeb_fx_type type)
+{
+  switch (type) {
+  case CUBEB_FX_ACOUSTIC_ECHO_CANCELER:
+    return "android/media/audiofx/AcousticEchoCanceler";
+  case CUBEB_FX_AUTOMATIC_GAIN_CONTROL:
+    return "android/media/audiofx/AutomaticGainControl";
+  case CUBEB_FX_NOISE_SUPPRESSOR:
+    return "android/media/audiofx/NoiseSuppressor";
+  case CUBEB_FX_SENTINEL__:
+    return nullptr;
+  }
+  return nullptr;
+}
+
+static constexpr const char *
+cubeb_fx_create_signature(cubeb_fx_type type)
+{
+  switch (type) {
+  case CUBEB_FX_ACOUSTIC_ECHO_CANCELER:
+    return "(I)Landroid/media/audiofx/AcousticEchoCanceler;";
+  case CUBEB_FX_AUTOMATIC_GAIN_CONTROL:
+    return "(I)Landroid/media/audiofx/AutomaticGainControl;";
+  case CUBEB_FX_NOISE_SUPPRESSOR:
+    return "(I)Landroid/media/audiofx/NoiseSuppressor;";
+  case CUBEB_FX_SENTINEL__:
+    return nullptr;
+  }
+  return nullptr;
+}
+
+struct cubeb_fx {
+  cubeb_jni * jni = nullptr;
+  cubeb_fx_type type = CUBEB_FX_SENTINEL__;
+  jobject obj = nullptr;
 };
 
 extern "C" cubeb_jni *
@@ -24,38 +73,120 @@ cubeb_jni_init()
   cubeb_jni * cubeb_jni_ptr = new cubeb_jni;
   assert(cubeb_jni_ptr);
 
-  // Find the audio manager object and make it global to call it from another
-  // method
-  jclass context_class = jni_env->FindClass("android/content/Context");
-  jfieldID audio_service_field = jni_env->GetStaticFieldID(
-      context_class, "AUDIO_SERVICE", "Ljava/lang/String;");
-  jstring jstr = (jstring)jni_env->GetStaticObjectField(context_class,
-                                                        audio_service_field);
-  jmethodID get_system_service_id =
-      jni_env->GetMethodID(context_class, "getSystemService",
-                           "(Ljava/lang/String;)Ljava/lang/Object;");
-  jobject audio_manager_obj =
-      jni_env->CallObjectMethod(ctx_obj, get_system_service_id, jstr);
-  cubeb_jni_ptr->s_audio_manager_obj =
-      reinterpret_cast<jobject>(jni_env->NewGlobalRef(audio_manager_obj));
-
-  // Make the audio manager class a global reference in order to preserve method
-  // id
-  jclass audio_manager_class = jni_env->FindClass("android/media/AudioManager");
-  cubeb_jni_ptr->s_audio_manager_class =
-      reinterpret_cast<jclass>(jni_env->NewGlobalRef(audio_manager_class));
-  cubeb_jni_ptr->s_get_output_latency_id =
-      jni_env->GetMethodID(audio_manager_class, "getOutputLatency", "(I)I");
-
-  jni_env->DeleteLocalRef(ctx_obj);
-  jni_env->DeleteLocalRef(context_class);
-  jni_env->DeleteLocalRef(jstr);
-  jni_env->DeleteLocalRef(audio_manager_obj);
-  jni_env->DeleteLocalRef(audio_manager_class);
+  {
+    // Find the audio manager object and make it global to call it from another
+    // method
+    jclass context_class = jni_env->FindClass("android/content/Context");
+    jfieldID audio_service_field = jni_env->GetStaticFieldID(
+        context_class, "AUDIO_SERVICE", "Ljava/lang/String;");
+    jstring jstr = (jstring)jni_env->GetStaticObjectField(context_class,
+                                                          audio_service_field);
+    jmethodID get_system_service_id =
+        jni_env->GetMethodID(context_class, "getSystemService",
+                             "(Ljava/lang/String;)Ljava/lang/Object;");
+    jobject audio_manager_obj =
+        jni_env->CallObjectMethod(ctx_obj, get_system_service_id, jstr);
+    cubeb_jni_ptr->s_audio_manager_obj =
+        reinterpret_cast<jobject>(jni_env->NewGlobalRef(audio_manager_obj));
+    jni_env->DeleteLocalRef(ctx_obj);
+    jni_env->DeleteLocalRef(context_class);
+    jni_env->DeleteLocalRef(jstr);
+    jni_env->DeleteLocalRef(audio_manager_obj);
+  }
+
+  {
+    // Make the audio manager class a global reference in order to preserve
+    // method id
+    jclass audio_manager_class =
+        jni_env->FindClass("android/media/AudioManager");
+    cubeb_jni_ptr->s_audio_manager_class =
+        reinterpret_cast<jclass>(jni_env->NewGlobalRef(audio_manager_class));
+    cubeb_jni_ptr->s_audio_manager_get_output_latency_id =
+        jni_env->GetMethodID(audio_manager_class, "getOutputLatency", "(I)I");
+    jni_env->DeleteLocalRef(audio_manager_class);
+  }
+
+  auto populate_fx_class = [&](cubeb_fx_type type) {
+    jclass c = jni_env->FindClass(cubeb_fx_name(type));
+    cubeb_jni::cubeb_fx_def & fx = cubeb_jni_ptr->s_fxs[type];
+    fx.clazz = reinterpret_cast<jclass>(jni_env->NewGlobalRef(c));
+    fx.static_function_is_available =
+        jni_env->GetStaticMethodID(c, "isAvailable", "()Z");
+    fx.static_function_create = jni_env->GetStaticMethodID(
+        c, "create", cubeb_fx_create_signature(type));
+    fx.method_set_enabled = jni_env->GetMethodID(c, "setEnabled", "(Z)I");
+    fx.method_release = jni_env->GetMethodID(c, "release", "()V");
+    jni_env->DeleteLocalRef(c);
+  };
+  populate_fx_class(CUBEB_FX_ACOUSTIC_ECHO_CANCELER);
+  populate_fx_class(CUBEB_FX_AUTOMATIC_GAIN_CONTROL);
+  populate_fx_class(CUBEB_FX_NOISE_SUPPRESSOR);
 
   return cubeb_jni_ptr;
 }
 
+extern "C" bool
+cubeb_fx_is_available(cubeb_jni * cubeb_jni_ptr, cubeb_fx_type type)
+{
+  JNIEnv * jni_env = cubeb_get_jni_env_for_thread();
+  cubeb_jni::cubeb_fx_def & fx = cubeb_jni_ptr->s_fxs[type];
+  return JNI_FALSE != jni_env->CallStaticBooleanMethod(
+                          fx.clazz, fx.static_function_is_available);
+}
+
+extern "C" cubeb_fx *
+cubeb_fx_init(cubeb_jni * cubeb_jni_ptr, cubeb_fx_type type, int audio_session)
+{
+  JNIEnv * jni_env = cubeb_get_jni_env_for_thread();
+  cubeb_jni::cubeb_fx_def & fx = cubeb_jni_ptr->s_fxs[type];
+  cubeb_jni_ptr->cubeb_fx_count += 1;
+
+  jobject obj = jni_env->CallStaticObjectMethod(
+      fx.clazz, fx.static_function_create, static_cast<jint>(audio_session));
+  if (!obj) {
+    return nullptr;
+  }
+
+  cubeb_fx * res = new cubeb_fx;
+  res->jni = cubeb_jni_ptr;
+  res->type = type;
+  res->obj = reinterpret_cast<jobject>(jni_env->NewGlobalRef(obj));
+
+  jni_env->DeleteLocalRef(obj);
+
+  return res;
+}
+
+extern "C" int
+cubeb_fx_set_enabled(cubeb_fx * cubeb_fx_ptr, bool enabled)
+{
+  assert(cubeb_fx_ptr);
+
+  JNIEnv * jni_env = cubeb_get_jni_env_for_thread();
+  cubeb_jni::cubeb_fx_def & fx = cubeb_fx_ptr->jni->s_fxs[cubeb_fx_ptr->type];
+  return static_cast<int>(
+      jni_env->CallIntMethod(cubeb_fx_ptr->obj, fx.method_set_enabled,
+                             static_cast<jboolean>(enabled)));
+}
+
+extern "C" void
+cubeb_fx_destroy(cubeb_fx * cubeb_fx_ptr)
+{
+  assert(cubeb_fx_ptr);
+
+  JNIEnv * jni_env = cubeb_get_jni_env_for_thread();
+
+  {
+    cubeb_jni::cubeb_fx_def & fx = cubeb_fx_ptr->jni->s_fxs[cubeb_fx_ptr->type];
+    jni_env->CallVoidMethod(cubeb_fx_ptr->obj, fx.method_release);
+  }
+
+  jni_env->DeleteGlobalRef(cubeb_fx_ptr->obj);
+
+  cubeb_fx_ptr->jni->cubeb_fx_count -= 1;
+  delete cubeb_fx_ptr;
+}
+
 extern "C" int
 cubeb_get_output_latency_from_jni(cubeb_jni * cubeb_jni_ptr)
 {
@@ -63,7 +194,7 @@ cubeb_get_output_latency_from_jni(cubeb_jni * cubeb_jni_ptr)
   JNIEnv * jni_env = cubeb_get_jni_env_for_thread();
   return jni_env->CallIntMethod(
       cubeb_jni_ptr->s_audio_manager_obj,
-      cubeb_jni_ptr->s_get_output_latency_id,
+      cubeb_jni_ptr->s_audio_manager_get_output_latency_id,
       AUDIO_STREAM_TYPE_MUSIC); // param: AudioManager.STREAM_MUSIC
 }
 
@@ -71,12 +202,16 @@ extern "C" void
 cubeb_jni_destroy(cubeb_jni * cubeb_jni_ptr)
 {
   assert(cubeb_jni_ptr);
+  assert(cubeb_jni_ptr->cubeb_fx_count == 0);
 
   JNIEnv * jni_env = cubeb_get_jni_env_for_thread();
   assert(jni_env);
 
   jni_env->DeleteGlobalRef(cubeb_jni_ptr->s_audio_manager_obj);
   jni_env->DeleteGlobalRef(cubeb_jni_ptr->s_audio_manager_class);
+  for (size_t i = 0; i < CUBEB_FX_SENTINEL__; ++i) {
+    jni_env->DeleteGlobalRef(cubeb_jni_ptr->s_fxs[i].clazz);
+  }
 
   delete cubeb_jni_ptr;
 }
diff --git a/src/cubeb-jni.h b/src/cubeb-jni.h
index d63629f..0a2d41a 100644
--- a/src/cubeb-jni.h
+++ b/src/cubeb-jni.h
@@ -2,6 +2,13 @@
 #define _CUBEB_JNI_H_
 
 typedef struct cubeb_jni cubeb_jni;
+typedef struct cubeb_fx cubeb_fx;
+enum cubeb_fx_type {
+  CUBEB_FX_ACOUSTIC_ECHO_CANCELER,
+  CUBEB_FX_AUTOMATIC_GAIN_CONTROL,
+  CUBEB_FX_NOISE_SUPPRESSOR,
+  CUBEB_FX_SENTINEL__,
+};
 
 #ifdef __cplusplus
 extern "C" {
@@ -9,8 +16,19 @@ extern "C" {
 
 cubeb_jni *
 cubeb_jni_init();
+
+bool
+cubeb_fx_is_available(cubeb_jni * cubeb_jni_ptr, cubeb_fx_type type);
+cubeb_fx *
+cubeb_fx_init(cubeb_jni * cubeb_jni_ptr, cubeb_fx_type type, int audio_session);
+int
+cubeb_fx_set_enabled(cubeb_fx * cubeb_fx_ptr, bool enabled);
+void
+cubeb_fx_destroy(cubeb_fx * cubeb_fx_ptr);
+
 int
 cubeb_get_output_latency_from_jni(cubeb_jni * cubeb_jni_ptr);
+
 void
 cubeb_jni_destroy(cubeb_jni * cubeb_jni_ptr);