Add ALSA Device Finder (#6079)

CMakeLists.txt

@@ -54,6 +54,10 @@ find_package(Gettext REQUIRED)
 find_package(PkgConfig REQUIRED)
 find_package(Protobuf REQUIRED)
 find_package(FFTW3)
+find_package(ALSA)
+if(ALSA_FOUND)
+  set(HAVE_ALSA ON)
+endif()
 
 find_library(PROTOBUF_STATIC_LIBRARY libprotobuf.a libprotobuf)
 

src/CMakeLists.txt

@@ -1187,6 +1187,12 @@ optional_source(HAVE_LIBPULSE
     engines/pulsedevicefinder.cpp
 )
 
+# ALSA integration
+optional_source(HAVE_ALSA
+  SOURCES
+    engines/alsadevicefinder.cpp
+)
+
 # Hack to add Clementine to the Unity system tray whitelist
 optional_source(LINUX
   SOURCES core/ubuntuunityhack.cpp
@@ -1305,6 +1311,10 @@ if(HAVE_LIBPULSE)
   target_link_libraries(clementine_lib ${LIBPULSE_LIBRARIES})
 endif()
 
+if(HAVE_ALSA)
+  target_link_libraries(clementine_lib ${ALSA_LIBRARIES})
+endif(HAVE_ALSA)
+
 if (APPLE)
   target_link_libraries(clementine_lib
     "-framework AppKit"

src/config.h.in

@@ -36,6 +36,7 @@
 #cmakedefine HAVE_LIBLASTFM1
 #cmakedefine HAVE_LIBMTP
 #cmakedefine HAVE_LIBPULSE
+#cmakedefine HAVE_ALSA
 #cmakedefine HAVE_MOODBAR
 #cmakedefine HAVE_SEAFILE
 #cmakedefine HAVE_SKYDRIVE

src/engines/alsadevicefinder.cpp

@@ -0,0 +1,107 @@
+/* This file is part of Clementine.
+   Copyright 2017, Jonas Kvinge <jonas@jkvinge.net>
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <alsa/asoundlib.h>
+#include <errno.h>
+#include <stdio.h>
+#include <boost/scope_exit.hpp>
+
+#include <QList>
+#include <QString>
+#include <QVariant>
+
+#include <core/logging.h>
+
+#include "alsadevicefinder.h"
+#include "devicefinder.h"
+
+AlsaDeviceFinder::AlsaDeviceFinder() : DeviceFinder("alsasink") {}
+
+QList<DeviceFinder::Device> AlsaDeviceFinder::ListDevices() {
+  QList<Device> ret;
+
+  snd_pcm_stream_name(SND_PCM_STREAM_PLAYBACK);
+
+  int card = -1;
+  snd_ctl_card_info_t* cardinfo;
+  snd_ctl_card_info_alloca(&cardinfo);
+  while (true) {
+    int result = snd_card_next(&card);
+    if (result < 0) {
+      qLog(Error) << "Unable to get soundcard:" << snd_strerror(result);
+      break;
+    }
+    if (card < 0) break;
+
+    char str[32];
+    snprintf(str, sizeof(str) - 1, "hw:%d", card);
+
+    snd_ctl_t* handle;
+    result = snd_ctl_open(&handle, str, 0);
+    if (result < 0) {
+      qLog(Error) << "Unable to open soundcard" << card << ":"
+                  << snd_strerror(result);
+      continue;
+    }
+    BOOST_SCOPE_EXIT(&handle) { snd_ctl_close(handle); }
+    BOOST_SCOPE_EXIT_END
+
+    result = snd_ctl_card_info(handle, cardinfo);
+    if (result < 0) {
+      qLog(Error) << "Control hardware failure for card" << card << ":"
+                  << snd_strerror(result);
+      continue;
+    }
+
+    int dev = -1;
+    snd_pcm_info_t* pcminfo;
+    snd_pcm_info_alloca(&pcminfo);
+    while (true) {
+      result = snd_ctl_pcm_next_device(handle, &dev);
+      if (result < 0) {
+        qLog(Error) << "Unable to get PCM for card" << card << ":"
+                    << snd_strerror(result);
+        continue;
+      }
+      if (dev < 0) break;
+
+      snd_pcm_info_set_device(pcminfo, dev);
+      snd_pcm_info_set_subdevice(pcminfo, 0);
+      snd_pcm_info_set_stream(pcminfo, SND_PCM_STREAM_PLAYBACK);
+
+      result = snd_ctl_pcm_info(handle, pcminfo);
+      if (result < 0) {
+        if (result != -ENOENT)
+          qLog(Error) << "Unable to get control digital audio info for card"
+                      << card << ":" << snd_strerror(result);
+        continue;
+      }
+
+      Device device;
+      device.description = QString("%1 %2")
+                               .arg(snd_ctl_card_info_get_name(cardinfo))
+                               .arg(snd_pcm_info_get_name(pcminfo));
+      device.device_property_value = QString("hw:%1,%2").arg(card).arg(dev);
+      device.icon_name = GuessIconName(device.description);
+      ret.append(device);
+    }
+  }
+
+  snd_config_update_free_global();
+
+  return ret;
+}

src/engines/alsadevicefinder.h

@@ -0,0 +1,33 @@
+/* This file is part of Clementine.
+   Copyright 2017, Jonas Kvinge <jonas@jkvinge.net>
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef ALSADEVICEFINDER_H
+#define ALSADEVICEFINDER_H
+
+#include <QList>
+
+#include "devicefinder.h"
+
+class AlsaDeviceFinder : public DeviceFinder {
+ public:
+  AlsaDeviceFinder();
+
+  virtual bool Initialise() { return true; }
+  virtual QList<Device> ListDevices();
+};
+
+#endif  // ALSADEVICEFINDER_H

src/engines/gstengine.cpp

@@ -58,6 +58,10 @@
 #include "engines/pulsedevicefinder.h"
 #endif
 
+#ifdef HAVE_ALSA
+#include "engines/alsadevicefinder.h"
+#endif
+
 #ifdef Q_OS_DARWIN
 #include "engines/osxdevicefinder.h"
 #endif
@@ -76,6 +80,7 @@
 #endif
 
 using std::shared_ptr;
+using std::unique_ptr;
 using std::vector;
 
 const char* GstEngine::kSettingsGroup = "GstEngine";
@@ -158,10 +163,23 @@ void GstEngine::InitialiseGstreamer() {
     plugin_names.insert(plugin.name);
   }
 
-  QList<DeviceFinder*> device_finders;
+  bool pa(false);
 #ifdef HAVE_LIBPULSE
-  device_finders.append(new PulseDeviceFinder);
+  unique_ptr<DeviceFinder> finder_pulse(new PulseDeviceFinder);
+  if (plugin_names.contains(finder_pulse->gstreamer_sink()) &&
+      finder_pulse->Initialise()) {
+    pa = true;
+    device_finders_.append(finder_pulse.release());
+  }
 #endif
+
+  QList<DeviceFinder*> device_finders;
+  if (!pa) {  // Only add alsa devices if pulseaudio is not enabled to avoid
+              // confusion.
+#ifdef HAVE_ALSA
+    device_finders.append(new AlsaDeviceFinder);
+#endif
+  }
 #ifdef Q_OS_DARWIN
   device_finders.append(new OsxDeviceFinder);
 #endif