Fallback to maxBlockLength if host doesn't support nominal

distrho/src/DistrhoPluginLV2.cpp

@@ -52,8 +52,9 @@ typedef std::map<const String, String> StringMap;
 class PluginLv2
 {
 public:
-    PluginLv2(const double sampleRate, const LV2_URID_Map* const uridMap, const LV2_Worker_Schedule* const worker)
-        : fPortControls(nullptr),
+    PluginLv2(const double sampleRate, const LV2_URID_Map* const uridMap, const LV2_Worker_Schedule* const worker, const bool usingNominal)
+        : fUsingNominal(usingNominal),
+          fPortControls(nullptr),
           fLastControlValues(nullptr),
           fSampleRate(sampleRate),
 #if DISTRHO_LV2_USE_EVENTS_IN || DISTRHO_LV2_USE_EVENTS_OUT
@@ -663,31 +664,39 @@ public:
         {
             if (options[i].key == fUridMap->map(fUridMap->handle, LV2_BUF_SIZE__nominalBlockLength))
             {
-                if (options[i].type == fUridMap->map(fUridMap->handle, LV2_ATOM__Int))
+                if (options[i].type == fURIDs.atomInt)
                 {
                     const int bufferSize(*(const int*)options[i].value);
                     fPlugin.setBufferSize(bufferSize);
-                    continue;
                 }
                 else
                 {
                     d_stderr("Host changed nominalBlockLength but with wrong value type");
-                    continue;
+                }
+            }
+            else if (options[i].key == fUridMap->map(fUridMap->handle, LV2_BUF_SIZE__maxBlockLength) && ! fUsingNominal)
+            {
+                if (options[i].type == fURIDs.atomInt)
+                {
+                    const int bufferSize(*(const int*)options[i].value);
+                    fPlugin.setBufferSize(bufferSize);
+                }
+                else
+                {
+                    d_stderr("Host changed maxBlockLength but with wrong value type");
                 }
             }
             else if (options[i].key == fUridMap->map(fUridMap->handle, LV2_CORE__sampleRate))
             {
-                if (options[i].type == fUridMap->map(fUridMap->handle, LV2_ATOM__Double))
+                if (options[i].type == fURIDs.atomDouble)
                 {
                     const double sampleRate(*(const double*)options[i].value);
                     fSampleRate = sampleRate;
                     fPlugin.setSampleRate(sampleRate);
-                    continue;
                 }
                 else
                 {
                     d_stderr("Host changed sampleRate but with wrong value type");
-                    continue;
                 }
             }
         }
@@ -815,6 +824,7 @@ public:
 
 private:
     PluginExporter fPlugin;
+    const bool fUsingNominal; // if false use maxBlockLength
 
     // LV2 ports
 #if DISTRHO_PLUGIN_NUM_INPUTS > 0
@@ -1007,29 +1017,44 @@ static LV2_Handle lv2_instantiate(const LV2_Descriptor*, double sampleRate, cons
 #endif
 
     d_lastBufferSize = 0;
+    usingNominal = false;
 
     for (int i=0; options[i].key != 0; ++i)
     {
         if (options[i].key == uridMap->map(uridMap->handle, LV2_BUF_SIZE__nominalBlockLength))
         {
             if (options[i].type == uridMap->map(uridMap->handle, LV2_ATOM__Int))
+            {
                 d_lastBufferSize = *(const int*)options[i].value;
+                usingNominal = true;
+            }
             else
+            {
                 d_stderr("Host provides nominalBlockLength but has wrong value type");
-
+            }
             break;
         }
+
+        if (options[i].key == uridMap->map(uridMap->handle, LV2_BUF_SIZE__maxBlockLength))
+        {
+            if (options[i].type == uridMap->map(uridMap->handle, LV2_ATOM__Int))
+                d_lastBufferSize = *(const int*)options[i].value;
+            else
+                d_stderr("Host provides maxBlockLength but has wrong value type");
+
+            // no break, continue in case host supports nominalBlockLength
+        }
     }
 
     if (d_lastBufferSize == 0)
     {
-        d_stderr("Host does not provide nominalBlockLength option");
+        d_stderr("Host does not provide nominalBlockLength or maxBlockLength options");
         d_lastBufferSize = 2048;
     }
 
     d_lastSampleRate = sampleRate;
 
-    return new PluginLv2(sampleRate, uridMap, worker);
+    return new PluginLv2(sampleRate, uridMap, worker, usingNominal);
 }
 
 #define instancePtr ((PluginLv2*)instance)