Turned enum PluginError into Common::Error, which in the future is to be used in more places. Help with this is highly welcome

svn-id: r34906

28 files changed, 97 insertions, 89 deletions

diff --git a/backends/midi/alsa.cpp b/backends/midi/alsa.cpp
index 5a978a0fd2..b78066cdd4 100644
--- a/backends/midi/alsa.cpp
+++ b/backends/midi/alsa.cpp
@@ -269,7 +269,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 #define perm_ok(pinfo,bits) ((snd_seq_port_info_get_capability(pinfo) & (bits)) == (bits))
@@ -315,10 +315,10 @@ MusicDevices AlsaMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError AlsaMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error AlsaMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_ALSA();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_ALSA_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/camd.cpp b/backends/midi/camd.cpp
index d6d5819a6e..bab047746b 100644
--- a/backends/midi/camd.cpp
+++ b/backends/midi/camd.cpp
@@ -177,7 +177,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices CamdMusicPlugin::getDevices() const {
@@ -188,10 +188,10 @@ MusicDevices CamdMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError CamdMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error CamdMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_CAMD();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_CAMD_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/coreaudio.cpp b/backends/midi/coreaudio.cpp
index bf35fb90ba..0d72a1576a 100644
--- a/backends/midi/coreaudio.cpp
+++ b/backends/midi/coreaudio.cpp
@@ -218,7 +218,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices CoreAudioMusicPlugin::getDevices() const {
@@ -229,10 +229,10 @@ MusicDevices CoreAudioMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError CoreAudioMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error CoreAudioMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_CORE();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_CORE_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/coremidi.cpp b/backends/midi/coremidi.cpp
index da82249792..e63788d154 100644
--- a/backends/midi/coremidi.cpp
+++ b/backends/midi/coremidi.cpp
@@ -190,7 +190,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices CoreMIDIMusicPlugin::getDevices() const {
@@ -201,10 +201,10 @@ MusicDevices CoreMIDIMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError CoreMIDIMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error CoreMIDIMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_CoreMIDI();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_CoreMIDI_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/dmedia.cpp b/backends/midi/dmedia.cpp
index b4bd426ca4..eb639cc6c8 100644
--- a/backends/midi/dmedia.cpp
+++ b/backends/midi/dmedia.cpp
@@ -189,7 +189,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices DMediaMusicPlugin::getDevices() const {
@@ -200,10 +200,10 @@ MusicDevices DMediaMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError DMediaMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error DMediaMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_DMEDIA();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_DMEDIA_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/quicktime.cpp b/backends/midi/quicktime.cpp
index a18eadcb30..3a21c65c20 100644
--- a/backends/midi/quicktime.cpp
+++ b/backends/midi/quicktime.cpp
@@ -274,7 +274,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices QuickTimeMusicPlugin::getDevices() const {
@@ -285,10 +285,10 @@ MusicDevices QuickTimeMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError QuickTimeMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error QuickTimeMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_QT();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_QT_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/seq.cpp b/backends/midi/seq.cpp
index 9e86181674..920356147f 100644
--- a/backends/midi/seq.cpp
+++ b/backends/midi/seq.cpp
@@ -184,7 +184,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices SeqMusicPlugin::getDevices() const {
@@ -195,10 +195,10 @@ MusicDevices SeqMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError SeqMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error SeqMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_SEQ();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_SEQ_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/stmidi.cpp b/backends/midi/stmidi.cpp
index addb23c6bd..6cba1b819d 100644
--- a/backends/midi/stmidi.cpp
+++ b/backends/midi/stmidi.cpp
@@ -119,7 +119,7 @@ public:
         }
 
         MusicDevices getDevices() const;
-        PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver)
+        Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver)
  const;
 };
 
@@ -131,10 +131,10 @@ MusicDevices StMidiMusicPlugin::getDevices() const {
         return devices;
 }
 
-PluginError StMidiMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error StMidiMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
         *mididriver = new MidiDriver_STMIDI();
 
-        return kNoError;
+        return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_STMIDI_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/timidity.cpp b/backends/midi/timidity.cpp
index b262fed88c..d13fc4b79a 100644
--- a/backends/midi/timidity.cpp
+++ b/backends/midi/timidity.cpp
@@ -525,7 +525,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices TimidityMusicPlugin::getDevices() const {
@@ -534,10 +534,10 @@ MusicDevices TimidityMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError TimidityMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error TimidityMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_TIMIDITY();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_TIMIDITY_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/windows.cpp b/backends/midi/windows.cpp
index c564c124fe..d1f79f4fa3 100644
--- a/backends/midi/windows.cpp
+++ b/backends/midi/windows.cpp
@@ -158,7 +158,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices WindowsMusicPlugin::getDevices() const {
@@ -169,10 +169,10 @@ MusicDevices WindowsMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError WindowsMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error WindowsMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_WIN();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_WIN_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/ypa1.cpp b/backends/midi/ypa1.cpp
index 88f9c3de8f..ab49136121 100644
--- a/backends/midi/ypa1.cpp
+++ b/backends/midi/ypa1.cpp
@@ -117,7 +117,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices YamahaPa1MusicPlugin::getDevices() const {
@@ -128,10 +128,10 @@ MusicDevices YamahaPa1MusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError YamahaPa1MusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error YamahaPa1MusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_YamahaPa1();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_YamahaPa1_create(Audio::Mixer *mixer) {
diff --git a/backends/midi/zodiac.cpp b/backends/midi/zodiac.cpp
index 456e4df43a..f17f6796b7 100644
--- a/backends/midi/zodiac.cpp
+++ b/backends/midi/zodiac.cpp
@@ -135,7 +135,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices ZodiacMusicPlugin::getDevices() const {
@@ -146,10 +146,10 @@ MusicDevices ZodiacMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError ZodiacMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error ZodiacMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_Zodiac();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_Zodiac_create(Audio::Mixer *mixer) {
diff --git a/base/main.cpp b/base/main.cpp
index 4245e6c3b1..cde4e4fd2c 100644
--- a/base/main.cpp
+++ b/base/main.cpp
@@ -132,18 +132,18 @@ static int runGame(const EnginePlugin *plugin, OSystem &system, const Common::St
 
 	// Create the game engine
 	Engine *engine = 0;
-	PluginError err = (*plugin)->createInstance(&system, &engine);
-	if (!engine || err != kNoError) {
+	Common::Error err = (*plugin)->createInstance(&system, &engine);
+	if (!engine || err != Common::kNoError) {
 		// TODO: Show an error dialog or so?
 		// TODO: Also take 'err' into consideration...
 		//GUI::MessageDialog alert("ScummVM could not find any game in the specified directory!");
 		//alert.runModal();
 		const char *errMsg = 0;
 		switch (err) {
-		case kInvalidPathError:
+		case Common::kInvalidPathError:
 			errMsg = "Invalid game path";
 			break;
-		case kNoGameDataFoundError:
+		case Common::kNoGameDataFoundError:
 			errMsg = "Unable to locate game data";
 			break;
 		default:
diff --git a/common/advancedDetector.cpp b/common/advancedDetector.cpp
index 1ec8c47715..71b83d0d62 100644
--- a/common/advancedDetector.cpp
+++ b/common/advancedDetector.cpp
@@ -220,7 +220,7 @@ GameList AdvancedMetaEngine::detectGames(const FSList &fslist) const {
 	return detectedGames;
 }
 
-PluginError AdvancedMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
+Common::Error AdvancedMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
 	assert(engine);
 	upgradeTargetIfNecessary(params);
 
diff --git a/common/advancedDetector.h b/common/advancedDetector.h
index b72b9fbfc4..d2a38d2835 100644
--- a/common/advancedDetector.h
+++ b/common/advancedDetector.h
@@ -201,7 +201,7 @@ public:
 	virtual GameList getSupportedGames() const;
 	virtual GameDescriptor findGame(const char *gameid) const;
 	virtual GameList detectGames(const FSList &fslist) const;
-	virtual PluginError createInstance(OSystem *syst, Engine **engine) const;
+	virtual Common::Error createInstance(OSystem *syst, Engine **engine) const;
 
 	// To be provided by subclasses
 	virtual bool createInstance(OSystem *syst, Engine **engine, const Common::ADGameDescription *desc) const = 0;
diff --git a/common/error.h b/common/error.h
index 90a140e08a..39d76a8c36 100644
--- a/common/error.h
+++ b/common/error.h
@@ -32,6 +32,8 @@
 
 /**
  * Errors used in the SaveFileManager class.
+ *
+ * @todo	Merge this partially into Common::Error. We only need a small subset of these errors, though.
  */
 enum SFMError {
 	SFM_NO_ERROR,			//Default state, indicates no error has been recorded
@@ -44,17 +46,26 @@ enum SFMError {
 	SFM_DIR_ROFS			//mkdir()::EROFS: The parent directory resides on a read-only file system
 };
 
+namespace Common {
+
 /**
  * Error codes which may be reported by plugins under various circumstances.
- * @todo Turn this into a global 'ErrorCode' enum used by all of ScummVM ?
+ *
+ * @todo Clarify the names, and add doxygen comments to each error.
+ * @todo Add more error values, e.g. for load/save errors. Use those in SaveFileManager,
+ *       (Meta)Engine save/load API, Engine::init() and Engine::go(), ...
+ * @todo Maybe add an API which keeps track of an error message,
+ *       similiar to SDL_SetError/SDL_GetError/SDL_ClearError?
  */
-enum PluginError {
-	kNoError = 0,	// No error occured
-	kInvalidPathError,
-	kNoGameDataFoundError,
-	kUnsupportedGameidError,
+enum Error {
+	kNoError = 0,				//!< No error occured
+	kInvalidPathError,			//!< Engine initialization: Invalid game path was passed
+	kNoGameDataFoundError,		//!< Engine initialization: No game data was found in the specified location
+	kUnsupportedGameidError,	//!< Engine initialization: Gameid not supported by this (Meta)Engine
 
-	kUnknownError		// Catch-all error, used if no other error code matches
+	kUnknownError				//!< Catch-all error, used if no other error code matches
 };
 
+} // End of namespace Common
+
 #endif //COMMON_ERROR_H
diff --git a/engines/metaengine.h b/engines/metaengine.h
index 24995cd41b..fb4c5c2938 100644
--- a/engines/metaengine.h
+++ b/engines/metaengine.h
@@ -75,9 +75,9 @@ public:
 	 * @param syst	Pointer to the global OSystem object
 	 * @param engine	Pointer to a pointer which the MetaEngine sets to
 	 *					the newly create Engine, or 0 in case of an error
-	 * @return		a PluginError describing the error which occurred, or kNoError
+	 * @return		a Common::Error describing the error which occurred, or kNoError
 	 */
-	virtual PluginError createInstance(OSystem *syst, Engine **engine) const = 0;
+	virtual Common::Error createInstance(OSystem *syst, Engine **engine) const = 0;
 
 	/**
 	 * Return a list of all save states associated with the given target.
diff --git a/engines/queen/queen.cpp b/engines/queen/queen.cpp
index 8740497587..50936f8bb7 100644
--- a/engines/queen/queen.cpp
+++ b/engines/queen/queen.cpp
@@ -65,7 +65,7 @@ public:
 	virtual SaveStateList listSaves(const char *target) const;
 	virtual void removeSaveState(const char *target, int slot) const;
 
-	virtual PluginError createInstance(OSystem *syst, Engine **engine) const;
+	virtual Common::Error createInstance(OSystem *syst, Engine **engine) const;
 };
 
 const char *QueenMetaEngine::getName() const {
@@ -174,10 +174,10 @@ void QueenMetaEngine::removeSaveState(const char *target, int slot) const {
 	g_system->getSavefileManager()->removeSavefile(filename.c_str());
 }
 
-PluginError QueenMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
+Common::Error QueenMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
 	assert(engine);
 	*engine = new Queen::QueenEngine(syst);
-	return kNoError;
+	return Common::kNoError;
 }
 
 #if PLUGIN_ENABLED_DYNAMIC(QUEEN)
diff --git a/engines/scumm/detection.cpp b/engines/scumm/detection.cpp
index 297e0b8efd..fc85e13250 100644
--- a/engines/scumm/detection.cpp
+++ b/engines/scumm/detection.cpp
@@ -682,7 +682,7 @@ public:
 	virtual GameDescriptor findGame(const char *gameid) const;
 	virtual GameList detectGames(const Common::FSList &fslist) const;
 	
-	virtual PluginError createInstance(OSystem *syst, Engine **engine) const;
+	virtual Common::Error createInstance(OSystem *syst, Engine **engine) const;
 
 	virtual SaveStateList listSaves(const char *target) const;
 	virtual void removeSaveState(const char *target, int slot) const;
@@ -765,7 +765,7 @@ GameList ScummMetaEngine::detectGames(const Common::FSList &fslist) const {
  *
  * This is heavily based on our MD5 detection scheme.
  */
-PluginError ScummMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
+Common::Error ScummMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
 	assert(syst);
 	assert(engine);
 	const char *gameid = ConfMan.get("gameid").c_str();
@@ -792,7 +792,7 @@ PluginError ScummMetaEngine::createInstance(OSystem *syst, Engine **engine) cons
 	Common::FSList fslist;
 	Common::FSNode dir(ConfMan.get("path"));
 	if (!dir.getChildren(fslist, Common::FSNode::kListFilesOnly)) {
-		return kInvalidPathError;
+		return Common::kInvalidPathError;
 	}
 
 	// Invoke the detector, but fixed to the specified gameid.
@@ -801,7 +801,7 @@ PluginError ScummMetaEngine::createInstance(OSystem *syst, Engine **engine) cons
 
 	// Unable to locate game data
 	if (results.empty()) {
-		return kNoGameDataFoundError;
+		return Common::kNoGameDataFoundError;
 	}
 
 	// No unique match found. If a platform override is present, try to
@@ -943,7 +943,7 @@ PluginError ScummMetaEngine::createInstance(OSystem *syst, Engine **engine) cons
 		error("Engine_SCUMM_create(): Unknown version of game engine");
 	}
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 const char *ScummMetaEngine::getName() const {
diff --git a/engines/sky/sky.cpp b/engines/sky/sky.cpp
index 8250766f1a..1abb3d94f6 100644
--- a/engines/sky/sky.cpp
+++ b/engines/sky/sky.cpp
@@ -23,8 +23,6 @@
  *
  */
 
-
-
 #include "base/plugins.h"
 
 #include "common/config-manager.h"
@@ -115,7 +113,7 @@ public:
 	virtual GameDescriptor findGame(const char *gameid) const;
 	virtual GameList detectGames(const Common::FSList &fslist) const;	
 
-	virtual PluginError createInstance(OSystem *syst, Engine **engine) const;
+	virtual Common::Error createInstance(OSystem *syst, Engine **engine) const;
 
 	virtual SaveStateList listSaves(const char *target) const;
 };
@@ -203,10 +201,10 @@ GameList SkyMetaEngine::detectGames(const Common::FSList &fslist) const {
 	return detectedGames;
 }
 
-PluginError SkyMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
+Common::Error SkyMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
 	assert(engine);
 	*engine = new Sky::SkyEngine(syst);
-	return kNoError;
+	return Common::kNoError;
 }
 
 SaveStateList SkyMetaEngine::listSaves(const char *target) const {
diff --git a/engines/sword1/sword1.cpp b/engines/sword1/sword1.cpp
index 982b6cf6e4..9a6bfac030 100644
--- a/engines/sword1/sword1.cpp
+++ b/engines/sword1/sword1.cpp
@@ -23,7 +23,6 @@
  *
  */
 
-
 #include "sword1/sword1.h"
 
 #include "base/plugins.h"
@@ -101,7 +100,7 @@ public:
 	virtual GameList detectGames(const Common::FSList &fslist) const;
 	virtual SaveStateList listSaves(const char *target) const;
 
-	virtual PluginError createInstance(OSystem *syst, Engine **engine) const;
+	virtual Common::Error createInstance(OSystem *syst, Engine **engine) const;
 };
 
 bool SwordMetaEngine::hasFeature(MetaEngineFeature f) const {
@@ -195,10 +194,10 @@ GameList SwordMetaEngine::detectGames(const Common::FSList &fslist) const {
 	return detectedGames;
 }
 
-PluginError SwordMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
+Common::Error SwordMetaEngine::createInstance(OSystem *syst, Engine **engine) const {
 	assert(engine);
 	*engine = new SwordEngine(syst);
-	return kNoError;
+	return Common::kNoError;
 }
 
 SaveStateList SwordMetaEngine::listSaves(const char *target) const {
diff --git a/engines/sword2/sword2.cpp b/engines/sword2/sword2.cpp
index 23751ea3ef..c596e2f8c0 100644
--- a/engines/sword2/sword2.cpp
+++ b/engines/sword2/sword2.cpp
@@ -87,7 +87,7 @@ public:
 	virtual SaveStateList listSaves(const char *target) const;
 	virtual void removeSaveState(const char *target, int slot) const;
 
-	virtual PluginError createInstance(OSystem *syst, Engine **engine) const;
+	virtual Common::Error createInstance(OSystem *syst, Engine **engine) const;
 };
 
 bool Sword2MetaEngine::hasFeature(MetaEngineFeature f) const {
@@ -211,14 +211,14 @@ void Sword2MetaEngine::removeSaveState(const char *target, int slot) const {
 	g_system->getSavefileManager()->removeSavefile(filename.c_str());
 }
 
-PluginError Sword2MetaEngine::createInstance(OSystem *syst, Engine **engine) const {
+Common::Error Sword2MetaEngine::createInstance(OSystem *syst, Engine **engine) const {
 	assert(syst);
 	assert(engine);
 
 	Common::FSList fslist;
 	Common::FSNode dir(ConfMan.get("path"));
 	if (!dir.getChildren(fslist, Common::FSNode::kListAll)) {
-		return kInvalidPathError;
+		return Common::kInvalidPathError;
 	}
 
 	// Invoke the detector
@@ -228,11 +228,11 @@ PluginError Sword2MetaEngine::createInstance(OSystem *syst, Engine **engine) con
 	for (uint i = 0; i < detectedGames.size(); i++) {
 		if (detectedGames[i].gameid() == gameid) {
 			*engine = new Sword2::Sword2Engine(syst);
-			return kNoError;
+			return Common::kNoError;
 		}
 	}
 
-	return kNoGameDataFoundError;
+	return Common::kNoGameDataFoundError;
 }
 
 #if PLUGIN_ENABLED_DYNAMIC(SWORD2)
diff --git a/sound/musicplugin.h b/sound/musicplugin.h
index bdbd07ad31..cd49942b83 100644
--- a/sound/musicplugin.h
+++ b/sound/musicplugin.h
@@ -100,9 +100,9 @@ public:
 	 * @param mixer			Pointer to the global Mixer object
 	 * @param mididriver	Pointer to a pointer which the MusicPluginObject sets
 	 *				to the newly create MidiDriver, or 0 in case of an error
-	 * @return		a PluginError describing the error which occurred, or kNoError
+	 * @return		a Common::Error describing the error which occurred, or kNoError
 	 */
-	virtual PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const = 0;
+	virtual Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const = 0;
 };
 
 
diff --git a/sound/null.cpp b/sound/null.cpp
index 7559a6d816..fb5cbf806a 100644
--- a/sound/null.cpp
+++ b/sound/null.cpp
@@ -46,13 +46,13 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
-PluginError NullMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error NullMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_NULL();
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MusicDevices NullMusicPlugin::getDevices() const {
diff --git a/sound/softsynth/adlib.cpp b/sound/softsynth/adlib.cpp
index 3898956e15..86ee466065 100644
--- a/sound/softsynth/adlib.cpp
+++ b/sound/softsynth/adlib.cpp
@@ -1529,7 +1529,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices AdlibEmuMusicPlugin::getDevices() const {
@@ -1538,10 +1538,10 @@ MusicDevices AdlibEmuMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError AdlibEmuMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error AdlibEmuMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_ADLIB(mixer);
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_ADLIB_create(Audio::Mixer *mixer) {
diff --git a/sound/softsynth/fluidsynth.cpp b/sound/softsynth/fluidsynth.cpp
index eff9f4123c..4bf68afaea 100644
--- a/sound/softsynth/fluidsynth.cpp
+++ b/sound/softsynth/fluidsynth.cpp
@@ -230,7 +230,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices FluidSynthMusicPlugin::getDevices() const {
@@ -239,7 +239,7 @@ MusicDevices FluidSynthMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError FluidSynthMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error FluidSynthMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_FluidSynth(mixer);
 
 	return kNoError;
diff --git a/sound/softsynth/mt32.cpp b/sound/softsynth/mt32.cpp
index 3e3f9d91ff..1987fee839 100644
--- a/sound/softsynth/mt32.cpp
+++ b/sound/softsynth/mt32.cpp
@@ -495,7 +495,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices MT32EmuMusicPlugin::getDevices() const {
@@ -504,10 +504,10 @@ MusicDevices MT32EmuMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError MT32EmuMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error MT32EmuMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_MT32(mixer);
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_MT32_create(Audio::Mixer *mixer) {
diff --git a/sound/softsynth/ym2612.cpp b/sound/softsynth/ym2612.cpp
index 2a08bf631e..efdf292150 100644
--- a/sound/softsynth/ym2612.cpp
+++ b/sound/softsynth/ym2612.cpp
@@ -766,7 +766,7 @@ public:
 	}
 
 	MusicDevices getDevices() const;
-	PluginError createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
+	Common::Error createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const;
 };
 
 MusicDevices TownsEmuMusicPlugin::getDevices() const {
@@ -775,10 +775,10 @@ MusicDevices TownsEmuMusicPlugin::getDevices() const {
 	return devices;
 }
 
-PluginError TownsEmuMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
+Common::Error TownsEmuMusicPlugin::createInstance(Audio::Mixer *mixer, MidiDriver **mididriver) const {
 	*mididriver = new MidiDriver_YM2612(mixer);
 
-	return kNoError;
+	return Common::kNoError;
 }
 
 MidiDriver *MidiDriver_YM2612_create(Audio::Mixer *mixer) {