Refactor: Rely on library type ID to detect audio plugins

Instead of checking the filename to see if a plugin is an audio plugin,
use the type identifier ("deng-plugin/audio" for audio plugins).

The audio plugins still use the "audio_" prefix so that AudioDriver can
locate them without checking each plugin's type, which requires loading
them into memory.

doomsday/engine/api/dd_plugin.h

@@ -40,12 +40,6 @@
  */
 #define DENG_PLUGIN_GLOBAL(name)    __DengPlugin_##name
 
-#if defined(UNIX) && !defined(MACOSX)
-#  define DENG_AUDIO_PLUGIN_NAME_PREFIX "libaudio_"
-#else
-#  define DENG_AUDIO_PLUGIN_NAME_PREFIX "audio_"
-#endif
-
 #define MAX_HOOKS           16
 #define HOOKF_EXCLUSIVE     0x01000000
 

doomsday/engine/portable/include/library.h

@@ -82,6 +82,16 @@ Library* Library_New(const char* filePath);
 
 void Library_Delete(Library* lib);
 
+/**
+ * Returns the type identifier of the library.
+ * @see de::Library
+ *
+ * @param lib  Library instance.
+ *
+ * @return Type identifier string, e.g., "deng-plugin/game".
+ */
+const char* Library_Type(const Library* lib);
+
 /**
  * Looks up a symbol from the library.
  *

doomsday/engine/portable/src/audiodriver.c

@@ -124,20 +124,29 @@ static void importInterfaces(driver_t* d)
 
 static int audioPluginFinder(const char* fileName, const char* absPath, void* ptr)
 {
+    int i;
     Str* path = (Str*) ptr;
-    if(!strncmp(fileName, Str_Text(path), Str_Length(path)) /* matching name? */ &&
-       (strlen(fileName) == Str_Length(path) /* no extension? */
-        || fileName[Str_Length(path)] == '.' /* extension follows right away? */))
+
+    // Check if the filename matches: [*]audio_name[.ext]
+    // (a regex or pattern match routine wouldn't hurt...)
+
+    for(i = 0; i <= strlen(fileName) - Str_Size(path); ++i)
     {
-        Str_Set(path, absPath);
-        return true; // Found it!
+        const char* fn = fileName + i;
+        if(!strncmp(fn, Str_Text(path), Str_Length(path)) /* matching name? */ &&
+           (strlen(fn) == Str_Length(path) /* no extension? */
+            || fn[Str_Length(path)] == '.' /* extension follows right away? */))
+        {
+            Str_Set(path, absPath);
+            return true; // Found it!
+        }
     }
     return false; // Keep looking...
 }
 
 static AutoStr* findAudioPluginPath(const char* name)
 {
-    AutoStr* path = Str_Appendf(AutoStr_New(), "%s%s", DENG_AUDIO_PLUGIN_NAME_PREFIX, name);
+    AutoStr* path = Str_Appendf(AutoStr_New(), "audio_%s", name);
     if(Library_IterateAvailableLibraries(audioPluginFinder, path))
     {
         // The full path of the library was returned in @a path.

doomsday/engine/portable/src/dd_plugin.c

@@ -69,20 +69,20 @@ static int loadPlugin(const char* fileName, const char* pluginPath, void* param)
     DENG_ASSERT(fileName && fileName[0]);
     DENG_ASSERT(pluginPath && pluginPath[0]);
 
-    if(!strncmp(fileName, DENG_AUDIO_PLUGIN_NAME_PREFIX,
-                strlen(DENG_AUDIO_PLUGIN_NAME_PREFIX)))
-    {
-        // The audio plugins are loaded later on demand by AudioDriver.
-        return false;
-    }
-
     plugin = Library_New(pluginPath);
     if(!plugin)
     {
         Con_Message("  loadPlugin: Did not load \"%s\" (%s).\n", pluginPath, Library_LastError());
         return 0; // Continue iteration.
     }
 
+    if(!strcmp(Library_Type(plugin), "deng-plugin/audio"))
+    {
+        // Audio plugins will be loaded later, on demand.
+        Library_Delete(plugin);
+        return 0;
+    }
+
     initializer = Library_Symbol(plugin, "DP_Initialize");
     if(!initializer)
     {

doomsday/engine/portable/src/library.cpp

@@ -32,6 +32,7 @@ struct library_s { // typedef Library
     Str* path;
     de::LibraryFile* libFile;
     bool isGamePlugin;
+    std::string typeId;
 
     library_s() : path(0), libFile(0), isGamePlugin(false) {}
 };
@@ -109,6 +110,7 @@ Library* Library_New(const char* filePath)
         Library* lib = new Library;
         lib->libFile = &libFile;
         lib->path = Str_Set(Str_NewStd(), filePath);
+        lib->typeId = libFile.library().type().toStdString();
         loadedLibs.append(lib);
 
         // Symbols from game plugins conflict with each other, so we have to
@@ -131,12 +133,21 @@ Library* Library_New(const char* filePath)
 void Library_Delete(Library *lib)
 {
     DENG_ASSERT(lib);
+
+    // Unload the library from memory.
     lib->libFile->clear();
+
     Str_Delete(lib->path);
     loadedLibs.removeOne(lib);
     delete lib;
 }
 
+const char* Library_Type(const Library* lib)
+{
+    DENG_ASSERT(lib);
+    return &lib->typeId[0];
+}
+
 void* Library_Symbol(Library* lib, const char* symbolName)
 {
     try

doomsday/libdeng2/include/de/core/library.h

@@ -133,8 +133,10 @@ namespace de
         virtual ~Library();
 
         /**
-         * Returns the type identifier of the library. This affects how libdeng2
-         * will treat the library.
+         * Returns the type identifier of the library. This affects how
+         * libdeng2 will treat the library. The type is determined
+         * automatically when the library is first loaded, and can then be
+         * queried at any time even after the library has been unloaded.
          */
         const String& type() const { return _type; }