From 33954a904fa2f23eb48039692e13a40485def23f Mon Sep 17 00:00:00 2001
From: Daniel Agar <daniel@agar.ca>
Date: Mon, 11 Oct 2021 14:04:26 -0400
Subject: [PATCH] lib/tunes: never play tunes if circuit breaker is set

---
 src/lib/tunes/CMakeLists.txt |  9 ++++++---
 src/lib/tunes/tunes.cpp      | 30 ++++++++++++++++++++++++++++++
 src/lib/tunes/tunes.h        |  2 ++
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/src/lib/tunes/CMakeLists.txt b/src/lib/tunes/CMakeLists.txt
index deeb8f3139..24b8557cf3 100644
--- a/src/lib/tunes/CMakeLists.txt
+++ b/src/lib/tunes/CMakeLists.txt
@@ -1,6 +1,6 @@
 ############################################################################
 #
-#   Copyright (c) 2017 PX4 Development Team. All rights reserved.
+#   Copyright (c) 2017-2021 PX4 Development Team. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -32,6 +32,9 @@
 ############################################################################
 
 px4_add_library(tunes
-	tunes.cpp
 	default_tunes.cpp
-)
\ No newline at end of file
+	tune_definition.h
+	tunes.cpp
+	tunes.h
+)
+target_link_libraries(tunes PRIVATE circuit_breaker)
diff --git a/src/lib/tunes/tunes.cpp b/src/lib/tunes/tunes.cpp
index a95b1b9567..e0371559af 100644
--- a/src/lib/tunes/tunes.cpp
+++ b/src/lib/tunes/tunes.cpp
@@ -38,6 +38,9 @@
 #include "tunes.h"
 
 #include <px4_platform_common/log.h>
+
+#include <lib/circuit_breaker/circuit_breaker.h>
+
 #include <math.h>
 #include <ctype.h>
 #include <errno.h>
@@ -56,6 +59,10 @@ Tunes::Tunes(unsigned default_note_length, NoteMode default_note_mode,
 	_default_octave(default_octave),
 	_default_tempo(default_tempo)
 {
+	if (circuit_breaker_enabled("CBRK_BUZZER", CBRK_BUZZER_KEY)) {
+		_tunes_disabled = true;
+	}
+
 	reset(false);
 }
 
@@ -152,6 +159,14 @@ void Tunes::set_string(const char *const string, uint8_t volume)
 
 Tunes::Status Tunes::get_next_note(unsigned &frequency, unsigned &duration, unsigned &silence, uint8_t &volume)
 {
+	if (_tunes_disabled) {
+		frequency = 0;
+		duration = 0;
+		silence = 0;
+		volume = 0;
+		return Tunes::Status::Stop;
+	}
+
 	Tunes::Status ret = get_next_note(frequency, duration, silence);
 
 	// Check if note should not be heard -> adjust volume to 0 to be safe.
@@ -167,6 +182,13 @@ Tunes::Status Tunes::get_next_note(unsigned &frequency, unsigned &duration, unsi
 
 Tunes::Status Tunes::get_next_note(unsigned &frequency, unsigned &duration, unsigned &silence)
 {
+	if (_tunes_disabled) {
+		frequency = 0;
+		duration = 0;
+		silence = 0;
+		return Tunes::Status::Stop;
+	}
+
 	// Return the values for frequency and duration if the custom msg was received.
 	if (_using_custom_msg) {
 		_using_custom_msg = false;
@@ -350,6 +372,10 @@ Tunes::Status Tunes::get_next_note(unsigned &frequency, unsigned &duration, unsi
 
 Tunes::Status Tunes::tune_end()
 {
+	if (_tunes_disabled) {
+		return Tunes::Status::Stop;
+	}
+
 	// Restore intial parameters.
 	reset(_repeat);
 
@@ -364,6 +390,10 @@ Tunes::Status Tunes::tune_end()
 
 Tunes::Status Tunes::tune_error()
 {
+	if (_tunes_disabled) {
+		return Tunes::Status::Stop;
+	}
+
 	// The tune appears to be bad (unexpected EOF, bad character, etc.).
 	_repeat = false;	// Don't loop on error.
 	reset(_repeat);
diff --git a/src/lib/tunes/tunes.h b/src/lib/tunes/tunes.h
index 195907c058..7ab240fde5 100644
--- a/src/lib/tunes/tunes.h
+++ b/src/lib/tunes/tunes.h
@@ -232,4 +232,6 @@ private:
 	uint8_t      _volume    = 0;
 
 	bool  _using_custom_msg = false;
+
+	bool _tunes_disabled{false};
 };