Instance: add Database attribute

Move from db/DatabaseGlue.cxx, eliminating global variable.

21 files changed, 106 insertions, 152 deletions

diff --git a/Makefile.am b/Makefile.am
index 6f2e9e388..5e3f3b260 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -205,7 +205,6 @@ src_mpd_SOURCES += \
 	src/db/Uri.hxx \
 	src/db/Directory.cxx src/db/Directory.hxx \
 	src/db/DirectorySave.cxx src/db/DirectorySave.hxx \
-	src/db/DatabaseSimple.hxx \
 	src/db/DatabaseGlue.cxx src/db/DatabaseGlue.hxx \
 	src/db/DatabaseSong.cxx src/db/DatabaseSong.hxx \
 	src/db/DatabasePrint.cxx src/db/DatabasePrint.hxx \
diff --git a/src/Instance.cxx b/src/Instance.cxx
index 229af0268..42d62ac7c 100644
--- a/src/Instance.cxx
+++ b/src/Instance.cxx
@@ -22,10 +22,18 @@
 #include "Partition.hxx"
 #include "Idle.hxx"
 #include "Stats.hxx"
-#include "db/DatabaseGlue.hxx"
+#include "db/DatabaseError.hxx"
 
 #ifdef ENABLE_DATABASE
 
+Database *
+Instance::GetDatabase(Error &error)
+{
+	if (database == nullptr)
+		error.Set(db_domain, DB_DISABLED, "No database");
+	return database;
+}
+
 void
 Instance::DeleteSong(const char *uri)
 {
@@ -35,8 +43,10 @@ Instance::DeleteSong(const char *uri)
 void
 Instance::DatabaseModified()
 {
+	assert(database != nullptr);
+
 	stats_invalidate();
-	partition->DatabaseModified(*GetDatabase());
+	partition->DatabaseModified(*database);
 	idle_add(IDLE_DATABASE);
 }
 
diff --git a/src/Instance.hxx b/src/Instance.hxx
index ea60072cb..9e3f92458 100644
--- a/src/Instance.hxx
+++ b/src/Instance.hxx
@@ -30,9 +30,11 @@ class NeighborGlue;
 
 #ifdef ENABLE_DATABASE
 #include "db/DatabaseListener.hxx"
+class Database;
 class UpdateService;
 #endif
 
+class Error;
 class ClientList;
 struct Partition;
 
@@ -55,6 +57,8 @@ struct Instance final
 #endif
 
 #ifdef ENABLE_DATABASE
+	Database *database;
+
 	UpdateService *update;
 #endif
 
@@ -69,6 +73,12 @@ struct Instance final
 	}
 
 #ifdef ENABLE_DATABASE
+	/**
+	 * Returns the global #Database instance.  May return nullptr
+	 * if this MPD configuration has no database (no
+	 * music_directory was configured).
+	 */
+	Database *GetDatabase(Error &error);
 
 	void DeleteSong(const char *uri);
 
diff --git a/src/Main.cxx b/src/Main.cxx
index d7d13e2b3..8a5ed7506 100644
--- a/src/Main.cxx
+++ b/src/Main.cxx
@@ -195,22 +195,26 @@ glue_db_init_and_load(void)
 	if (param == nullptr)
 		return true;
 
+	bool is_simple;
 	Error error;
-	if (!DatabaseGlobalInit(*main_loop, *instance, *param, error))
+	instance->database = DatabaseGlobalInit(*main_loop, *instance, *param,
+						is_simple, error);
+	if (instance->database == nullptr)
 		FatalError(error);
 
 	delete allocated;
 
-	if (!DatabaseGlobalOpen(error))
+	if (!instance->database->Open(error))
 		FatalError(error);
 
-	if (!db_is_simple())
+	if (!is_simple)
 		return true;
 
-	instance->update = new UpdateService(*main_loop, db_get_simple());
+	SimpleDatabase &db = *(SimpleDatabase *)instance->database;
+	instance->update = new UpdateService(*main_loop, db);
 
 	/* run database update after daemonization? */
-	return db_exists();
+	return db.FileExists();
 }
 
 #endif
@@ -577,8 +581,8 @@ int mpd_main(int argc, char *argv[])
 
 #ifdef ENABLE_DATABASE
 	delete instance->update;
-
-	DatabaseGlobalDeinit();
+	instance->database->Close();
+	delete instance->database;
 #endif
 
 #ifdef ENABLE_SQLITE
diff --git a/src/PlaylistPrint.cxx b/src/PlaylistPrint.cxx
index 377da25c9..2e29ac6a2 100644
--- a/src/PlaylistPrint.cxx
+++ b/src/PlaylistPrint.cxx
@@ -23,7 +23,8 @@
 #include "Playlist.hxx"
 #include "queue/QueuePrint.hxx"
 #include "SongPrint.hxx"
-#include "db/DatabaseGlue.hxx"
+#include "Partition.hxx"
+#include "Instance.hxx"
 #include "db/DatabasePlugin.hxx"
 #include "client/Client.hxx"
 #include "input/InputStream.hxx"
@@ -115,7 +116,7 @@ playlist_print_changes_position(Client &client,
 static bool
 PrintSongDetails(Client &client, const char *uri_utf8)
 {
-	const Database *db = GetDatabase();
+	const Database *db = client.partition.instance.database;
 	if (db == nullptr)
 		return false;
 
diff --git a/src/SongLoader.cxx b/src/SongLoader.cxx
index 90df42824..08aa01296 100644
--- a/src/SongLoader.cxx
+++ b/src/SongLoader.cxx
@@ -33,6 +33,13 @@
 #include <assert.h>
 #include <string.h>
 
+#ifdef ENABLE_DATABASE
+
+SongLoader::SongLoader(const Client &_client)
+	:client(&_client), db(_client.GetDatabase(IgnoreError())) {}
+
+#endif
+
 DetachedSong *
 SongLoader::LoadFile(const char *path_utf8, Error &error) const
 {
diff --git a/src/SongLoader.hxx b/src/SongLoader.hxx
index 997c0fb18..9914db8e6 100644
--- a/src/SongLoader.hxx
+++ b/src/SongLoader.hxx
@@ -45,19 +45,16 @@ class SongLoader {
 
 public:
 #ifdef ENABLE_DATABASE
-	SongLoader(const Client *_client, const Database *_db=nullptr)
-		:client(_client), db(_db) {}
-	explicit SongLoader(const Client &_client)
-		:client(&_client), db(nullptr) {}
+	explicit SongLoader(const Client &_client);
 	explicit SongLoader(const Database *_db)
 		:client(nullptr), db(_db) {}
-	explicit SongLoader(std::nullptr_t)
-		:client(nullptr), db(nullptr) {}
+	explicit SongLoader(const Client &_client, const Database *_db)
+		:client(&_client), db(_db) {}
 #else
 	explicit SongLoader(const Client &_client)
 		:client(&_client) {}
-	explicit SongLoader(const Client *_client)
-		:client(_client) {}
+	explicit SongLoader(std::nullptr_t)
+		:client(nullptr) {}
 #endif
 
 	gcc_nonnull_all
diff --git a/src/StateFile.cxx b/src/StateFile.cxx
index 6c01be53c..e46af1c3e 100644
--- a/src/StateFile.cxx
+++ b/src/StateFile.cxx
@@ -23,9 +23,9 @@
 #include "PlaylistState.hxx"
 #include "fs/TextFile.hxx"
 #include "Partition.hxx"
+#include "Instance.hxx"
 #include "mixer/Volume.hxx"
 #include "SongLoader.hxx"
-#include "db/DatabaseGlue.hxx"
 #include "fs/FileSystem.hxx"
 #include "util/Domain.hxx"
 #include "Log.hxx"
@@ -98,7 +98,11 @@ StateFile::Read()
 		return;
 	}
 
-	const SongLoader song_loader(nullptr, GetDatabase());
+#ifdef ENABLE_DATABASE
+	const SongLoader song_loader(partition.instance.database);
+#else
+	const SongLoader song_loader(nullptr);
+#endif
 
 	const char *line;
 	while ((line = file.ReadLine()) != NULL) {
diff --git a/src/Stats.cxx b/src/Stats.cxx
index 4051d8049..c5fcc69e2 100644
--- a/src/Stats.cxx
+++ b/src/Stats.cxx
@@ -21,8 +21,9 @@
 #include "Stats.hxx"
 #include "PlayerControl.hxx"
 #include "client/Client.hxx"
+#include "Partition.hxx"
+#include "Instance.hxx"
 #include "db/Selection.hxx"
-#include "db/DatabaseGlue.hxx"
 #include "db/DatabasePlugin.hxx"
 #include "util/Error.hxx"
 #include "system/Clock.hxx"
@@ -60,8 +61,6 @@ void stats_global_init(void)
 void
 stats_invalidate()
 {
-	assert(GetDatabase() != nullptr);
-
 	stats_validity = StatsValidity::INVALID;
 }
 
@@ -132,7 +131,7 @@ stats_print(Client &client)
 		      (unsigned long)(client.player_control.GetTotalPlayTime() + 0.5));
 
 #ifdef ENABLE_DATABASE
-	const Database *db = GetDatabase();
+	const Database *db = client.partition.instance.database;
 	if (db != nullptr)
 		db_stats_print(client, *db);
 #endif
diff --git a/src/client/Client.cxx b/src/client/Client.cxx
index ce99faa89..c62c759e9 100644
--- a/src/client/Client.cxx
+++ b/src/client/Client.cxx
@@ -20,5 +20,17 @@
 #include "config.h"
 #include "ClientInternal.hxx"
 #include "util/Domain.hxx"
+#include "Partition.hxx"
+#include "Instance.hxx"
 
 const Domain client_domain("client");
+
+#ifdef ENABLE_DATABASE
+
+const Database *
+Client::GetDatabase(Error &error) const
+{
+	return partition.instance.GetDatabase(error);
+}
+
+#endif
diff --git a/src/client/Client.hxx b/src/client/Client.hxx
index 708b0d03d..006ffc98c 100644
--- a/src/client/Client.hxx
+++ b/src/client/Client.hxx
@@ -38,6 +38,7 @@ struct sockaddr;
 class EventLoop;
 class Path;
 struct Partition;
+class Database;
 
 class Client final : private FullyBufferedSocket, TimeoutMonitor {
 public:
@@ -169,6 +170,11 @@ public:
 	 */
 	bool AllowFile(Path path_fs, Error &error) const;
 
+	/**
+	 * Wrapper for Instance::GetDatabase().
+	 */
+	const Database *GetDatabase(Error &error) const;
+
 private:
 	/* virtual methods from class BufferedSocket */
 	virtual InputResult OnSocketInput(void *data, size_t length) override;
diff --git a/src/command/DatabaseCommands.cxx b/src/command/DatabaseCommands.cxx
index b458b3756..ef6fb922e 100644
--- a/src/command/DatabaseCommands.cxx
+++ b/src/command/DatabaseCommands.cxx
@@ -120,7 +120,7 @@ handle_searchaddpl(Client &client, int argc, char *argv[])
 	}
 
 	Error error;
-	const Database *db = GetDatabase(error);
+	const Database *db = client.GetDatabase(error);
 	if (db == nullptr)
 		return print_error(client, error);
 
diff --git a/src/command/PlaylistCommands.cxx b/src/command/PlaylistCommands.cxx
index 07cc177d6..0997cc68d 100644
--- a/src/command/PlaylistCommands.cxx
+++ b/src/command/PlaylistCommands.cxx
@@ -19,7 +19,6 @@
 
 #include "config.h"
 #include "PlaylistCommands.hxx"
-#include "db/DatabaseGlue.hxx"
 #include "db/DatabasePlaylist.hxx"
 #include "CommandError.hxx"
 #include "PlaylistPrint.hxx"
@@ -193,7 +192,7 @@ handle_playlistadd(Client &client, gcc_unused int argc, char *argv[])
 		success = spl_append_uri(playlist, loader, uri, error);
 	} else {
 #ifdef ENABLE_DATABASE
-		const Database *db = GetDatabase(error);
+		const Database *db = client.GetDatabase(error);
 		if (db == nullptr)
 			return print_error(client, error);
 
diff --git a/src/command/StickerCommands.cxx b/src/command/StickerCommands.cxx
index 9e526b0e0..bf3660b85 100644
--- a/src/command/StickerCommands.cxx
+++ b/src/command/StickerCommands.cxx
@@ -28,6 +28,9 @@
 #include "sticker/StickerDatabase.hxx"
 #include "CommandError.hxx"
 #include "protocol/Result.hxx"
+#include "client/Client.hxx"
+#include "Partition.hxx"
+#include "Instance.hxx"
 #include "util/Error.hxx"
 
 #include <string.h>
@@ -52,7 +55,7 @@ static CommandResult
 handle_sticker_song(Client &client, int argc, char *argv[])
 {
 	Error error;
-	const Database *db = GetDatabase(error);
+	const Database *db = client.GetDatabase(error);
 	if (db == nullptr)
 		return print_error(client, error);
 
diff --git a/src/db/DatabaseGlue.cxx b/src/db/DatabaseGlue.cxx
index f320633c7..30c244334 100644
--- a/src/db/DatabaseGlue.cxx
+++ b/src/db/DatabaseGlue.cxx
@@ -19,30 +19,18 @@
 
 #include "config.h"
 #include "DatabaseGlue.hxx"
-#include "DatabaseSimple.hxx"
 #include "Registry.hxx"
 #include "DatabaseError.hxx"
-#include "Directory.hxx"
 #include "util/Error.hxx"
 #include "config/ConfigData.hxx"
-#include "Stats.hxx"
 #include "DatabasePlugin.hxx"
-#include "plugins/SimpleDatabasePlugin.hxx"
 
-#include <assert.h>
 #include <string.h>
 
-static Database *db;
-static bool db_is_open;
-static bool is_simple;
-
-bool
+Database *
 DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
-		   const config_param &param, Error &error)
+		   const config_param &param, bool &is_simple, Error &error)
 {
-	assert(db == nullptr);
-	assert(!db_is_open);
-
 	const char *plugin_name =
 		param.GetBlockValue("plugin", "simple");
 	is_simple = strcmp(plugin_name, "simple") == 0;
@@ -51,79 +39,8 @@ DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
 	if (plugin == nullptr) {
 		error.Format(db_domain,
 			     "No such database plugin: %s", plugin_name);
-		return false;
+		return nullptr;
 	}
 
-	db = plugin->create(loop, listener, param, error);
-	return db != nullptr;
-}
-
-void
-DatabaseGlobalDeinit(void)
-{
-	if (db_is_open)
-		db->Close();
-
-	if (db != nullptr)
-		delete db;
-}
-
-const Database *
-GetDatabase()
-{
-	assert(db == nullptr || db_is_open);
-
-	return db;
-}
-
-const Database *
-GetDatabase(Error &error)
-{
-	assert(db == nullptr || db_is_open);
-
-	if (db == nullptr)
-		error.Set(db_domain, DB_DISABLED, "No database");
-
-	return db;
-}
-
-bool
-db_is_simple(void)
-{
-	assert(db == nullptr || db_is_open);
-
-	return is_simple;
-}
-
-SimpleDatabase &
-db_get_simple()
-{
-	assert(is_simple);
-	assert(db != nullptr);
-
-	return *(SimpleDatabase *)db;
-}
-
-bool
-DatabaseGlobalOpen(Error &error)
-{
-	assert(db != nullptr);
-	assert(!db_is_open);
-
-	if (!db->Open(error))
-		return false;
-
-	db_is_open = true;
-
-	return true;
-}
-
-bool
-db_exists()
-{
-	assert(db != nullptr);
-	assert(db_is_open);
-	assert(db_is_simple());
-
-	return ((SimpleDatabase *)db)->GetUpdateStamp() > 0;
+	return plugin->create(loop, listener, param, error);
 }
diff --git a/src/db/DatabaseGlue.hxx b/src/db/DatabaseGlue.hxx
index 78032edb2..f562b6d41 100644
--- a/src/db/DatabaseGlue.hxx
+++ b/src/db/DatabaseGlue.hxx
@@ -32,31 +32,11 @@ class Error;
  * Initialize the database library.
  *
  * @param param the database configuration block
+ * @param is_simple returns whether this is the "simple" database
+ * plugin
  */
-bool
+Database *
 DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
-		   const config_param &param, Error &error);
-
-void
-DatabaseGlobalDeinit(void);
-
-bool
-DatabaseGlobalOpen(Error &error);
-
-/**
- * Returns the global #Database instance.  May return nullptr if this MPD
- * configuration has no database (no music_directory was configured).
- */
-gcc_const
-const Database *
-GetDatabase();
-
-/**
- * Returns the global #Database instance.  May return nullptr if this MPD
- * configuration has no database (no music_directory was configured).
- */
-gcc_pure
-const Database *
-GetDatabase(Error &error);
+		   const config_param &param, bool &is_simple, Error &error);
 
 #endif
diff --git a/src/db/DatabasePrint.cxx b/src/db/DatabasePrint.cxx
index 9ed0b0826..669a804be 100644
--- a/src/db/DatabasePrint.cxx
+++ b/src/db/DatabasePrint.cxx
@@ -28,7 +28,6 @@
 #include "LightSong.hxx"
 #include "LightDirectory.hxx"
 #include "PlaylistInfo.hxx"
-#include "DatabaseGlue.hxx"
 #include "DatabasePlugin.hxx"
 
 #include <functional>
@@ -129,7 +128,7 @@ bool
 db_selection_print(Client &client, const DatabaseSelection &selection,
 		   bool full, Error &error)
 {
-	const Database *db = GetDatabase(error);
+	const Database *db = client.GetDatabase(error);
 	if (db == nullptr)
 		return false;
 
@@ -173,7 +172,7 @@ searchStatsForSongsIn(Client &client, const char *name,
 		      const SongFilter *filter,
 		      Error &error)
 {
-	const Database *db = GetDatabase(error);
+	const Database *db = client.GetDatabase(error);
 	if (db == nullptr)
 		return false;
 
@@ -229,7 +228,7 @@ listAllUniqueTags(Client &client, int type,
 		  const SongFilter *filter,
 		  Error &error)
 {
-	const Database *db = GetDatabase(error);
+	const Database *db = client.GetDatabase(error);
 	if (db == nullptr)
 		return false;
 
diff --git a/src/db/DatabaseQueue.cxx b/src/db/DatabaseQueue.cxx
index ee1dbd57c..f2a0951a6 100644
--- a/src/db/DatabaseQueue.cxx
+++ b/src/db/DatabaseQueue.cxx
@@ -22,6 +22,7 @@
 #include "DatabaseGlue.hxx"
 #include "DatabasePlugin.hxx"
 #include "Partition.hxx"
+#include "Instance.hxx"
 #include "util/Error.hxx"
 #include "DetachedSong.hxx"
 #include "Mapper.hxx"
@@ -47,7 +48,7 @@ bool
 AddFromDatabase(Partition &partition, const DatabaseSelection &selection,
 		Error &error)
 {
-	const Database *db = GetDatabase(error);
+	const Database *db = partition.instance.GetDatabase(error);
 	if (db == nullptr)
 		return false;
 
diff --git a/src/db/DatabaseSimple.hxx b/src/db/DatabaseSimple.hxx
index c0f84ab79..1e527958f 100644
--- a/src/db/DatabaseSimple.hxx
+++ b/src/db/DatabaseSimple.hxx
@@ -35,10 +35,6 @@ class Error;
 bool
 db_is_simple(void);
 
-gcc_pure
-SimpleDatabase &
-db_get_simple();
-
 /**
  * Returns true if there is a valid database file on the disk.
  *
diff --git a/src/db/plugins/SimpleDatabasePlugin.hxx b/src/db/plugins/SimpleDatabasePlugin.hxx
index 8c7978a91..83434393c 100644
--- a/src/db/plugins/SimpleDatabasePlugin.hxx
+++ b/src/db/plugins/SimpleDatabasePlugin.hxx
@@ -59,6 +59,9 @@ public:
 
 	bool Save(Error &error);
 
+	/**
+	 * Returns true if there is a valid database file on the disk.
+	 */
 	bool FileExists() const {
 		return mtime > 0;
 	}
diff --git a/test/test_translate_song.cxx b/test/test_translate_song.cxx
index 3c94ed4bc..bc1ae82d6 100644
--- a/test/test_translate_song.cxx
+++ b/test/test_translate_song.cxx
@@ -137,6 +137,12 @@ DetachedSong::Update()
 	return false;
 }
 
+const Database *
+Client::GetDatabase(gcc_unused Error &error) const
+{
+	return reinterpret_cast<const Database *>(this);
+}
+
 bool
 Client::AllowFile(gcc_unused Path path_fs, gcc_unused Error &error) const
 {
@@ -220,7 +226,7 @@ class TranslateSongTest : public CppUnit::TestFixture {
 	void TestInsecure() {
 		/* illegal because secure=false */
 		DetachedSong song1 (uri1);
-		const SongLoader loader(reinterpret_cast<const Client *>(1));
+		const SongLoader loader(*reinterpret_cast<const Client *>(1));
 		CPPUNIT_ASSERT(!playlist_check_translate_song(song1, nullptr,
 							      loader));
 	}
@@ -261,7 +267,8 @@ class TranslateSongTest : public CppUnit::TestFixture {
 	void TestRelative() {
 		const Database &db = *reinterpret_cast<const Database *>(1);
 		const SongLoader secure_loader(&db);
-		const SongLoader insecure_loader(reinterpret_cast<const Client *>(1), &db);
+		const SongLoader insecure_loader(*reinterpret_cast<const Client *>(1),
+						 &db);
 
 		/* map to music_directory */
 		DetachedSong song1("bar.ogg", MakeTag2b());