From f589acaac9e172d8d2758066b6c67b0adc771435 Mon Sep 17 00:00:00 2001
From: Gunnar Beutner <gbeutner@serenityos.org>
Date: Wed, 16 Jun 2021 14:04:40 +0200
Subject: [PATCH] AudioServer: Put the m_zero_filled_buffer variable into the
 .bss segment

This way we don't have to allocate this at runtime. I'm intentionally
not using static constexpr here because that would put the variable
into the .rodata segment and would therefore increase the binary by
4kB.

The old code also failed to free() the buffer in the destructor, however
that wasn't much of an issue because the Mixer object exists throughout
the program's entire lifetime.
---
 Userland/Services/AudioServer/Mixer.cpp | 6 +++---
 Userland/Services/AudioServer/Mixer.h   | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/Userland/Services/AudioServer/Mixer.cpp b/Userland/Services/AudioServer/Mixer.cpp
index e1ed63d1ce..a0a9aecfeb 100644
--- a/Userland/Services/AudioServer/Mixer.cpp
+++ b/Userland/Services/AudioServer/Mixer.cpp
@@ -14,6 +14,8 @@
 
 namespace AudioServer {
 
+u8 Mixer::m_zero_filled_buffer[4096];
+
 Mixer::Mixer()
     : m_device(Core::File::construct("/dev/audio", this))
     , m_sound_thread(Threading::Thread::construct(
@@ -31,8 +33,6 @@ Mixer::Mixer()
     pthread_mutex_init(&m_pending_mutex, nullptr);
     pthread_cond_init(&m_pending_cond, nullptr);
 
-    m_zero_filled_buffer = (u8*)malloc(4096);
-    bzero(m_zero_filled_buffer, 4096);
     m_sound_thread->start();
 }
 
@@ -86,7 +86,7 @@ void Mixer::mix()
         }
 
         if (m_muted) {
-            m_device->write(m_zero_filled_buffer, 4096);
+            m_device->write(m_zero_filled_buffer, sizeof(m_zero_filled_buffer));
         } else {
             Array<u8, 4096> buffer;
             OutputMemoryStream stream { buffer };
diff --git a/Userland/Services/AudioServer/Mixer.h b/Userland/Services/AudioServer/Mixer.h
index c3af89158d..c5a6fde437 100644
--- a/Userland/Services/AudioServer/Mixer.h
+++ b/Userland/Services/AudioServer/Mixer.h
@@ -117,7 +117,7 @@ private:
     bool m_muted { false };
     int m_main_volume { 100 };
 
-    u8* m_zero_filled_buffer { nullptr };
+    static u8 m_zero_filled_buffer[4096];
 
     void mix();
 };