{input,mixer}/alsa: move code to lib/alsa/NonBlock.cxx

Makefile.am

@@ -256,6 +256,9 @@ UPNP_SOURCES = \
 	src/lib/upnp/WorkQueue.hxx \
 	src/lib/upnp/Action.hxx
 
+ALSA_SOURCES = \
+	src/lib/alsa/NonBlock.cxx src/lib/alsa/NonBlock.hxx
+
 #
 # Android native library
 #
@@ -1294,6 +1297,7 @@ INPUT_LIBS = \
 
 if ENABLE_ALSA
 libinput_a_SOURCES += \
+	$(ALSA_SOURCES) \
 	src/input/plugins/AlsaInputPlugin.cxx \
 	src/input/plugins/AlsaInputPlugin.hxx
 INPUT_LIBS += $(ALSA_LIBS)
@@ -1412,6 +1416,7 @@ liboutput_plugins_a_SOURCES += \
 	src/output/plugins/AlsaOutputPlugin.cxx \
 	src/output/plugins/AlsaOutputPlugin.hxx
 libmixer_plugins_a_SOURCES += \
+	$(ALSA_SOURCES) \
 	src/mixer/plugins/volume_mapping.h \
 	src/mixer/plugins/volume_mapping.c \
 	src/mixer/plugins/AlsaMixerPlugin.cxx

src/input/plugins/AlsaInputPlugin.cxx

@@ -26,6 +26,7 @@
 
 #include "config.h"
 #include "AlsaInputPlugin.hxx"
+#include "lib/alsa/NonBlock.hxx"
 #include "../InputPlugin.hxx"
 #include "../AsyncInputStream.hxx"
 #include "event/Call.hxx"
@@ -177,20 +178,7 @@ AlsaInputStream::PrepareSockets()
 		return std::chrono::steady_clock::duration(-1);
 	}
 
-	int count = snd_pcm_poll_descriptors_count(capture_handle);
-	if (count <= 0) {
-		ClearSocketList();
-		return std::chrono::steady_clock::duration(-1);
-	}
-
-	struct pollfd *pfds = pfd_buffer.Get(count);
-
-	count = snd_pcm_poll_descriptors(capture_handle, pfds, count);
-	if (count < 0)
-		count = 0;
-
-	ReplaceSocketList(pfds, count);
-	return std::chrono::steady_clock::duration(-1);
+	return PrepareAlsaPcmSockets(*this, capture_handle, pfd_buffer);
 }
 
 void

src/lib/alsa/NonBlock.cxx

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2003-2017 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "NonBlock.hxx"
+#include "event/MultiSocketMonitor.hxx"
+
+std::chrono::steady_clock::duration
+PrepareAlsaPcmSockets(MultiSocketMonitor &m, snd_pcm_t *pcm,
+		      ReusableArray<pollfd> &pfd_buffer)
+{
+	int count = snd_pcm_poll_descriptors_count(pcm);
+	if (count <= 0) {
+		m.ClearSocketList();
+		return std::chrono::steady_clock::duration(-1);
+	}
+
+	struct pollfd *pfds = pfd_buffer.Get(count);
+
+	count = snd_pcm_poll_descriptors(pcm, pfds, count);
+	if (count < 0)
+		count = 0;
+
+	m.ReplaceSocketList(pfds, count);
+	return std::chrono::steady_clock::duration(-1);
+}
+
+std::chrono::steady_clock::duration
+PrepareAlsaMixerSockets(MultiSocketMonitor &m, snd_mixer_t *mixer,
+			ReusableArray<pollfd> &pfd_buffer)
+{
+	int count = snd_mixer_poll_descriptors_count(mixer);
+	if (count <= 0) {
+		m.ClearSocketList();
+		return std::chrono::steady_clock::duration(-1);
+	}
+
+	struct pollfd *pfds = pfd_buffer.Get(count);
+
+	count = snd_mixer_poll_descriptors(mixer, pfds, count);
+	if (count < 0)
+		count = 0;
+
+	m.ReplaceSocketList(pfds, count);
+	return std::chrono::steady_clock::duration(-1);
+}

src/lib/alsa/NonBlock.hxx

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2003-2017 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_ALSA_NON_BLOCK_HXX
+#define MPD_ALSA_NON_BLOCK_HXX
+
+#include "check.h"
+#include "util/ReusableArray.hxx"
+
+#include <alsa/asoundlib.h>
+
+#include <chrono>
+
+class MultiSocketMonitor;
+
+/**
+ * Update #MultiSocketMonitor's socket list from
+ * snd_pcm_poll_descriptors().  To be called from
+ * MultiSocketMonitor::PrepareSockets().
+ */
+std::chrono::steady_clock::duration
+PrepareAlsaPcmSockets(MultiSocketMonitor &m, snd_pcm_t *pcm,
+		      ReusableArray<pollfd> &pfd_buffer);
+
+/**
+ * Update #MultiSocketMonitor's socket list from
+ * snd_mixer_poll_descriptors().  To be called from
+ * MultiSocketMonitor::PrepareSockets().
+ */
+std::chrono::steady_clock::duration
+PrepareAlsaMixerSockets(MultiSocketMonitor &m, snd_mixer_t *mixer,
+		      ReusableArray<pollfd> &pfd_buffer);
+
+#endif

src/mixer/plugins/AlsaMixerPlugin.cxx

@@ -18,6 +18,7 @@
  */
 
 #include "config.h"
+#include "lib/alsa/NonBlock.hxx"
 #include "mixer/MixerInternal.hxx"
 #include "mixer/Listener.hxx"
 #include "output/OutputAPI.hxx"
@@ -108,18 +109,7 @@ AlsaMixerMonitor::PrepareSockets()
 		return std::chrono::steady_clock::duration(-1);
 	}
 
-	int count = snd_mixer_poll_descriptors_count(mixer);
-	if (count <= 0)
-		count = 0;
-
-	struct pollfd *pfds = pfd_buffer.Get(count);
-
-	count = snd_mixer_poll_descriptors(mixer, pfds, count);
-	if (count < 0)
-		count = 0;
-
-	ReplaceSocketList(pfds, count);
-	return std::chrono::steady_clock::duration(-1);
+	return PrepareAlsaMixerSockets(*this, mixer, pfd_buffer);
 }
 
 void