Instance: add Database attribute

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

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);
 }

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

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;
 

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;
 

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.
  *

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;
 	}