From 358c94f5ddd9460ebb009ffb3f9a1a31ace35136 Mon Sep 17 00:00:00 2001
From: Jonas Oreland <jonaso@webrtc.org>
Date: Thu, 20 Feb 2025 20:39:38 +0100
Subject: [PATCH] AudioState extensions

This patch modifies AudioState to always call InitRecording
before StartRecording(). This makes it possible to do
SetRecording(false) + SetRecording(true), which before this
patch would not actually work if there was sending streams.

The only way was to add/remove streams...via SDP operations, puh :(.

Bonus: We also needed to modifu AndroidAudioDeviceModule
(which is a thin wrapper) so that StopRecording() will
call AudioInput->StopRecording() even when recording is not
enabled.

BUG=b/397376626

Change-Id: I954b5caab11225b544c3e6a78c5dde357d4eedb5
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/378140
Commit-Queue: Jonas Oreland <jonaso@webrtc.org>
Auto-Submit: Jonas Oreland <jonaso@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#43946}
---
 audio/audio_state.cc                          |  7 +++--
 audio/audio_state_unittest.cc                 | 31 +++++++++++++++++++
 .../jni/audio_device/audio_device_module.cc   |  2 --
 3 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/audio/audio_state.cc b/audio/audio_state.cc
index a0861eef6b..fb0a140360 100644
--- a/audio/audio_state.cc
+++ b/audio/audio_state.cc
@@ -141,13 +141,16 @@ void AudioState::SetRecording(bool enabled) {
   RTC_LOG(LS_INFO) << "SetRecording(" << enabled << ")";
   RTC_DCHECK_RUN_ON(&thread_checker_);
   if (recording_enabled_ != enabled) {
+    auto* adm = config_.audio_device_module.get();
     recording_enabled_ = enabled;
     if (enabled) {
       if (!sending_streams_.empty()) {
-        config_.audio_device_module->StartRecording();
+        if (adm->InitRecording() == 0) {
+          adm->StartRecording();
+        }
       }
     } else {
-      config_.audio_device_module->StopRecording();
+      adm->StopRecording();
     }
   }
 }
diff --git a/audio/audio_state_unittest.cc b/audio/audio_state_unittest.cc
index 954e6c19c3..63a722948f 100644
--- a/audio/audio_state_unittest.cc
+++ b/audio/audio_state_unittest.cc
@@ -26,6 +26,7 @@ namespace test {
 namespace {
 
 using ::testing::_;
+using ::testing::InSequence;
 using ::testing::Matcher;
 using ::testing::NiceMock;
 using ::testing::StrictMock;
@@ -357,6 +358,36 @@ TEST_P(AudioStateTest,
       audio_buffer, n_samples_out, &elapsed_time_ms, &ntp_time_ms);
 }
 
+TEST_P(AudioStateTest, AlwaysCallInitRecordingBeforeStartRecording) {
+  ConfigHelper helper(GetParam());
+  rtc::scoped_refptr<internal::AudioState> audio_state(
+      rtc::make_ref_counted<internal::AudioState>(helper.config()));
+
+  auto* adm = reinterpret_cast<MockAudioDeviceModule*>(
+      helper.config().audio_device_module.get());
+
+  MockAudioSendStream stream;
+  {
+    InSequence s;
+    EXPECT_CALL(*adm, InitRecording());
+    EXPECT_CALL(*adm, StartRecording());
+    audio_state->AddSendingStream(&stream, kSampleRate, kNumberOfChannels);
+  }
+
+  EXPECT_CALL(*adm, StopRecording());
+  audio_state->SetRecording(false);
+
+  {
+    InSequence s;
+    EXPECT_CALL(*adm, InitRecording());
+    EXPECT_CALL(*adm, StartRecording());
+    audio_state->SetRecording(true);
+  }
+
+  EXPECT_CALL(*adm, StopRecording());
+  audio_state->RemoveSendingStream(&stream);
+}
+
 INSTANTIATE_TEST_SUITE_P(AudioStateTest,
                          AudioStateTest,
                          Values(ConfigHelper::Params({false, false}),
diff --git a/sdk/android/src/jni/audio_device/audio_device_module.cc b/sdk/android/src/jni/audio_device/audio_device_module.cc
index dafe18010f..2c571185fa 100644
--- a/sdk/android/src/jni/audio_device/audio_device_module.cc
+++ b/sdk/android/src/jni/audio_device/audio_device_module.cc
@@ -298,8 +298,6 @@ class AndroidAudioDeviceModule : public AudioDeviceModule {
     RTC_DLOG(LS_INFO) << __FUNCTION__;
     if (!initialized_)
       return -1;
-    if (!Recording())
-      return 0;
     audio_device_buffer_->StopRecording();
     int32_t result = input_->StopRecording();
     RTC_DLOG(LS_INFO) << "output: " << result;