Android: obtain music directory from Environment.getExternalStoragePublicDirectory()

Makefile.am

@@ -252,12 +252,17 @@ libjava_a_SOURCES = \
 	src/java/File.cxx src/java/File.hxx \
 	src/java/String.cxx src/java/String.hxx
 
+noinst_LIBRARIES += libandroid.a
+libandroid_a_SOURCES = \
+	src/android/Environment.cxx src/android/Environment.hxx
+libandroid_a_CPPFLAGS = $(AM_CPPFLAGS) -Iandroid/build/include
+
 noinst_LIBRARIES += libmain.a
 libmain_a_SOURCES = \
 	src/Main.cxx src/Main.hxx
 libmain_a_CPPFLAGS = $(AM_CPPFLAGS) -Iandroid/build/include
 
-src_mpd_LDADD += libjava.a
+src_mpd_LDADD += libandroid.a libjava.a
 
 all-local: android/build/bin/Main-debug.apk
 clean-local:

src/Main.cxx

@@ -92,6 +92,7 @@
 #ifdef ANDROID
 #include "java/Global.hxx"
 #include "java/File.hxx"
+#include "android/Environment.hxx"
 #include "org_musicpd_Bridge.h"
 #endif
 
@@ -679,8 +680,11 @@ Java_org_musicpd_Bridge_run(JNIEnv *env, jclass)
 {
 	Java::Init(env);
 	Java::File::Initialise(env);
+	Environment::Initialise(env);
 
 	mpd_main(0, nullptr);
+
+	Environment::Deinitialise(env);
 }
 
 #endif

src/android/Environment.cxx

@@ -0,0 +1,117 @@
+/*
+Copyright_License {
+
+  XCSoar Glide Computer - http://www.xcsoar.org/
+  Copyright (C) 2000-2013 The XCSoar Project
+  A detailed list of copyright holders can be found in the file "AUTHORS".
+
+  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+}
+*/
+
+#include "Environment.hxx"
+#include "java/Class.hxx"
+#include "java/String.hxx"
+#include "java/File.hxx"
+#include "util/StringUtil.hxx"
+
+namespace Environment {
+	static Java::TrivialClass cls;
+	static jmethodID getExternalStorageDirectory_method;
+	static jmethodID getExternalStoragePublicDirectory_method;
+
+	static jstring getExternalStorageDirectory(JNIEnv *env);
+};
+
+void
+Environment::Initialise(JNIEnv *env)
+{
+	cls.Find(env, "android/os/Environment");
+
+	getExternalStorageDirectory_method =
+		env->GetStaticMethodID(cls, "getExternalStorageDirectory",
+				       "()Ljava/io/File;");
+
+	getExternalStoragePublicDirectory_method =
+		env->GetStaticMethodID(cls, "getExternalStoragePublicDirectory",
+				       "(Ljava/lang/String;)Ljava/io/File;");
+}
+
+void
+Environment::Deinitialise(JNIEnv *env)
+{
+	cls.Clear(env);
+}
+
+static jstring
+ToAbsolutePathChecked(JNIEnv *env, jobject file)
+{
+	if (file == nullptr)
+		return nullptr;
+
+	jstring path = Java::File::getAbsolutePath(env, file);
+	env->DeleteLocalRef(file);
+	return path;
+}
+
+static jstring
+Environment::getExternalStorageDirectory(JNIEnv *env)
+{
+	jobject file = env->CallStaticObjectMethod(cls,
+						   getExternalStorageDirectory_method);
+	return ToAbsolutePathChecked(env, file);
+}
+
+char *
+Environment::getExternalStorageDirectory(char *buffer, size_t max_size)
+{
+	JNIEnv *env = Java::GetEnv();
+
+	jstring value = getExternalStorageDirectory(env);
+	if (value == nullptr)
+		return nullptr;
+
+	Java::String value2(env, value);
+	value2.CopyTo(env, buffer, max_size);
+	return buffer;
+}
+
+static jstring
+getExternalStoragePublicDirectory(JNIEnv *env, const char *type)
+{
+	if (Environment::getExternalStoragePublicDirectory_method == nullptr)
+		/* needs API level 8 */
+		return nullptr;
+
+	Java::String type2(env, type);
+	jobject file = env->CallStaticObjectMethod(Environment::cls,
+						   Environment::getExternalStoragePublicDirectory_method,
+						   type2.Get());
+	return ToAbsolutePathChecked(env, file);
+}
+
+char *
+Environment::getExternalStoragePublicDirectory(char *buffer, size_t max_size,
+					       const char *type)
+{
+	JNIEnv *env = Java::GetEnv();
+	jstring path = ::getExternalStoragePublicDirectory(env, type);
+	if (path == nullptr)
+		return nullptr;
+
+	Java::String path2(env, path);
+	path2.CopyTo(env, buffer, max_size);
+	return buffer;
+}

src/android/Environment.hxx

@@ -0,0 +1,43 @@
+/*
+Copyright_License {
+
+  XCSoar Glide Computer - http://www.xcsoar.org/
+  Copyright (C) 2000-2013 The XCSoar Project
+  A detailed list of copyright holders can be found in the file "AUTHORS".
+
+  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+}
+*/
+
+#ifndef MPD_ANDROID_ENVIRONMENT_HXX
+#define MPD_ANDROID_ENVIRONMENT_HXX
+
+#include <jni.h>
+#include <stddef.h>
+
+namespace Environment {
+	void Initialise(JNIEnv *env);
+	void Deinitialise(JNIEnv *env);
+
+	/**
+	 * Determine the mount point of the external SD card.
+	 */
+	char *getExternalStorageDirectory(char *buffer, size_t max_size);
+
+	char *getExternalStoragePublicDirectory(char *buffer, size_t max_size,
+						const char *type);
+};
+
+#endif

src/fs/StandardDirectory.cxx

@@ -20,7 +20,7 @@
 #include "config.h"
 
 // Use X Desktop guidelines where applicable
-#if !defined(__APPLE__) && !defined(WIN32)
+#if !defined(__APPLE__) && !defined(WIN32) && !defined(ANDROID)
 #define USE_XDG
 #endif
 
@@ -47,6 +47,11 @@
 #include <utility>
 #endif
 
+#ifdef ANDROID
+#include "java/Global.hxx"
+#include "android/Environment.hxx"
+#endif
+
 #ifndef WIN32
 class PasswdEntry
 {
@@ -240,6 +245,14 @@ AllocatedPath GetUserMusicDir()
 	return GetStandardDir(CSIDL_MYMUSIC);	
 #elif defined(USE_XDG)
 	return GetUserDir("XDG_MUSIC_DIR");
+#elif defined(ANDROID)
+	char buffer[1024];
+	if (Environment::getExternalStoragePublicDirectory(buffer,
+							   sizeof(buffer),
+							   "Music") == nullptr)
+		return AllocatedPath::Null();
+
+	return AllocatedPath::FromUTF8(buffer);
 #else
 	return AllocatedPath::Null();
 #endif