From fb51bdb892fcb7ffe74a01becda566fd6bc9a431 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Mon, 23 Jun 2014 11:56:58 +0200
Subject: [PATCH] statically allocate midi-options

fixes possible segfault when the data in the vector
goes out of scope due to RVO.
---
 libs/backends/alsa/alsa_audiobackend.cc   | 12 +++++++-----
 libs/backends/alsa/alsa_audiobackend.h    |  1 +
 libs/backends/dummy/dummy_audiobackend.cc | 13 ++++++++-----
 libs/backends/dummy/dummy_audiobackend.h  |  2 ++
 4 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/libs/backends/alsa/alsa_audiobackend.cc b/libs/backends/alsa/alsa_audiobackend.cc
index 82a3399f6f..a61d3a1869 100644
--- a/libs/backends/alsa/alsa_audiobackend.cc
+++ b/libs/backends/alsa/alsa_audiobackend.cc
@@ -38,6 +38,7 @@ using namespace ARDOUR;
 
 static std::string s_instance_name;
 size_t AlsaAudioBackend::_max_buffer_size = 8192;
+std::vector<std::string> AlsaAudioBackend::_midi_options;
 
 AlsaAudioBackend::AlsaAudioBackend (AudioEngine& e, AudioBackendInfo& info)
 	: AudioBackend (e, info)
@@ -403,11 +404,12 @@ AlsaAudioBackend::midi_device_info(std::string const name) const {
 std::vector<std::string>
 AlsaAudioBackend::enumerate_midi_options () const
 {
-	std::vector<std::string> m;
-	m.push_back (_("None"));
-	m.push_back (_("ALSA raw devices"));
-	m.push_back (_("ALSA sequencer"));
-	return m;
+	if (_midi_options.empty()) {
+		_midi_options.push_back (_("None"));
+		_midi_options.push_back (_("ALSA raw devices"));
+		_midi_options.push_back (_("ALSA sequencer"));
+	}
+	return _midi_options;
 }
 
 std::vector<AudioBackend::DeviceStatus>
diff --git a/libs/backends/alsa/alsa_audiobackend.h b/libs/backends/alsa/alsa_audiobackend.h
index f8f7ea3ea3..089420e78e 100644
--- a/libs/backends/alsa/alsa_audiobackend.h
+++ b/libs/backends/alsa/alsa_audiobackend.h
@@ -302,6 +302,7 @@ class AlsaAudioBackend : public AudioBackend {
 		bool  _freewheeling;
 		bool  _measure_latency;
 
+		static std::vector<std::string> _midi_options;
 		std::string _audio_device;
 		std::string _midi_driver_option;
 
diff --git a/libs/backends/dummy/dummy_audiobackend.cc b/libs/backends/dummy/dummy_audiobackend.cc
index cd09a64c65..dc53010443 100644
--- a/libs/backends/dummy/dummy_audiobackend.cc
+++ b/libs/backends/dummy/dummy_audiobackend.cc
@@ -32,6 +32,7 @@ using namespace ARDOUR;
 
 static std::string s_instance_name;
 size_t DummyAudioBackend::_max_buffer_size = 8192;
+std::vector<std::string> DummyAudioBackend::_midi_options;
 
 DummyAudioBackend::DummyAudioBackend (AudioEngine& e, AudioBackendInfo& info)
 	: AudioBackend (e, info)
@@ -249,15 +250,17 @@ DummyAudioBackend::systemic_output_latency () const
 	return _systemic_output_latency;
 }
 
+
 /* MIDI */
 std::vector<std::string>
 DummyAudioBackend::enumerate_midi_options () const
 {
-	std::vector<std::string> m;
-	m.push_back (_("1 in, 1 out"));
-	m.push_back (_("2 in, 2 out"));
-	m.push_back (_("8 in, 8 out"));
-	return m;
+	if (_midi_options.empty()) {
+		_midi_options.push_back (_("1 in, 1 out"));
+		_midi_options.push_back (_("2 in, 2 out"));
+		_midi_options.push_back (_("8 in, 8 out"));
+	}
+	return _midi_options;
 }
 
 int
diff --git a/libs/backends/dummy/dummy_audiobackend.h b/libs/backends/dummy/dummy_audiobackend.h
index d4732f5eeb..638bb9f312 100644
--- a/libs/backends/dummy/dummy_audiobackend.h
+++ b/libs/backends/dummy/dummy_audiobackend.h
@@ -292,6 +292,8 @@ class DummyAudioBackend : public AudioBackend {
 
 	private:
 		std::string _instance_name;
+		static std::vector<std::string> _midi_options;
+
 		bool  _running;
 		bool  _freewheeling;