upnp: move library initialization to Init.cxx

Allow calling UpnpGlobalInit() multiple times.

Makefile.am

@@ -217,6 +217,7 @@ src_mpd_SOURCES = \
 	src/Timer.cxx
 
 UPNP_SOURCES = \
+	src/lib/upnp/Init.cxx src/lib/upnp/Init.hxx \
 	src/lib/upnp/Device.cxx src/lib/upnp/Device.hxx \
 	src/lib/upnp/ContentDirectoryService.cxx src/lib/upnp/ContentDirectoryService.hxx \
 	src/lib/upnp/Discovery.cxx src/lib/upnp/Discovery.hxx \

src/lib/upnp/Init.cxx

@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2003-2014 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 "Init.hxx"
+#include "Domain.hxx"
+#include "thread/Mutex.hxx"
+#include "util/Error.hxx"
+
+#include <upnp/upnp.h>
+#include <upnp/upnptools.h>
+#include <upnp/ixml.h>
+
+static Mutex upnp_init_mutex;
+static unsigned upnp_ref;
+
+static bool
+DoInit(Error &error)
+{
+	auto code = UpnpInit(0, 0);
+	if (code != UPNP_E_SUCCESS) {
+		error.Format(upnp_domain, code,
+			     "UpnpInit() failed: %s",
+			     UpnpGetErrorMessage(code));
+		return false;
+	}
+
+	UpnpSetMaxContentLength(2000*1024);
+
+	// Servers sometimes make error (e.g.: minidlna returns bad utf-8)
+	ixmlRelaxParser(1);
+
+	return true;
+}
+
+bool
+UpnpGlobalInit(Error &error)
+{
+	const ScopeLock protect(upnp_init_mutex);
+
+	if (upnp_ref == 0 && !DoInit(error))
+		return false;
+
+	++upnp_ref;
+	return true;
+}
+
+void
+UpnpGlobalFinish()
+{
+	const ScopeLock protect(upnp_init_mutex);
+
+	assert(upnp_ref > 0);
+
+	if (--upnp_ref == 0)
+		UpnpFinish();
+}

src/lib/upnp/Init.hxx

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2003-2014 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_UPNP_INIT_HXX
+#define MPD_UPNP_INIT_HXX
+
+#include "check.h"
+
+class Error;
+
+bool
+UpnpGlobalInit(Error &error);
+
+void
+UpnpGlobalFinish();
+
+#endif

src/lib/upnp/upnpplib.cxx

@@ -21,33 +21,24 @@
 #include "upnpplib.hxx"
 #include "Callback.hxx"
 #include "Domain.hxx"
+#include "Init.hxx"
 #include "Log.hxx"
 
-#include <upnp/ixml.h>
 #include <upnp/upnptools.h>
 
 LibUPnP::LibUPnP()
 {
-	auto code = UpnpInit(0, 0);
-	if (code != UPNP_E_SUCCESS) {
-		init_error.Format(upnp_domain, code,
-				  "UpnpInit() failed: %s",
-				  UpnpGetErrorMessage(code));
+	if (!UpnpGlobalInit(init_error))
 		return;
-	}
 
-	UpnpSetMaxContentLength(2000*1024);
-
-	code = UpnpRegisterClient(o_callback, nullptr, &m_clh);
+	auto code = UpnpRegisterClient(o_callback, nullptr, &m_clh);
 	if (code != UPNP_E_SUCCESS) {
+		UpnpGlobalFinish();
 		init_error.Format(upnp_domain, code,
 				  "UpnpRegisterClient() failed: %s",
 				  UpnpGetErrorMessage(code));
 		return;
 	}
-
-	// Servers sometimes make error (e.g.: minidlna returns bad utf-8)
-	ixmlRelaxParser(1);
 }
 
 int
@@ -65,8 +56,5 @@ LibUPnP::o_callback(Upnp_EventType et, void* evp, void* cookie)
 
 LibUPnP::~LibUPnP()
 {
-	int error = UpnpFinish();
-	if (error != UPNP_E_SUCCESS)
-		FormatError(upnp_domain, "UpnpFinish() failed: %s",
-			    UpnpGetErrorMessage(error));
+	UpnpGlobalFinish();
 }