Audio: Make sure AL and ALC extensions are both detected.

Signed-off-by: Squareys <Squareys@googlemail.com>

src/Magnum/Audio/Context.cpp

@@ -72,6 +72,9 @@ Context::Context(const Configuration& config) {
         std::exit(1);
     }
 
+    alcMakeContextCurrent(_context);
+    _current = this;
+
     /* Add all extensions to a map for faster lookup */
     std::unordered_map<std::string, Extension> extensionMap;
     for(const Extension& extension: Extension::extensions())
@@ -87,9 +90,6 @@ Context::Context(const Configuration& config) {
         }
     }
 
-    alcMakeContextCurrent(_context);
-    _current = this;
-
     /* Print some info */
     Debug() << "Audio Renderer:" << rendererString() << "by" << vendorString();
     Debug() << "OpenAL version:" << versionString();
@@ -105,9 +105,16 @@ Context::~Context() {
 std::vector<std::string> Context::extensionStrings() const {
     std::vector<std::string> extensions;
 
-    /* Don't crash when glGetString() returns nullptr */
-    const char* e = reinterpret_cast<const char*>(alGetString(AL_EXTENSIONS));
-    if(e) extensions = Utility::String::splitWithoutEmptyParts(e, ' ');
+    /* Don't crash when alGetString() returns nullptr */
+    const char* alExts = reinterpret_cast<const char*>(alGetString(AL_EXTENSIONS));
+    if(alExts) extensions = Utility::String::splitWithoutEmptyParts(alExts, ' ');
+
+    /* Add ALC extensions aswell */
+    const char* alcExts = reinterpret_cast<const char*>(alcGetString(_device, ALC_EXTENSIONS));
+    if(alcExts) {
+        auto splitAlcExts = Utility::String::splitWithoutEmptyParts(alcExts, ' ');
+        extensions.insert(extensions.end(), splitAlcExts.begin(), splitAlcExts.end());
+    }
 
     return extensions;
 }

src/Magnum/Audio/Context.h

@@ -140,7 +140,8 @@ class MAGNUM_AUDIO_EXPORT Context {
          * @ref supportedExtensions(), @ref Extension::extensions() or
          * @ref isExtensionSupported() for alternatives.
          * @see @fn_al{Get} with @def_al{NUM_EXTENSIONS}, @fn_al{GetString}
-         *      with @def_al{EXTENSIONS}
+         *      with @def_al{EXTENSIONS}, @fn_alc{GetString} with
+         *      @def_alc{EXTENSIONS}
          */
         std::vector<std::string> extensionStrings() const;