add wavetable saving

src/engine/engine.cpp

@@ -1719,16 +1719,7 @@ SafeWriter* DivEngine::saveFur() {
   for (int i=0; i<song.waveLen; i++) {
     DivWavetable* wave=song.wave[i];
     wavePtr[i]=w->tell();
-    w->write("WAVE",4);
-    w->writeI(0);
-    
-    w->writeC(0); // name
-    w->writeI(wave->len);
-    w->writeI(wave->min);
-    w->writeI(wave->max);
-    for (int j=0; j<wave->len; j++) {
-      w->writeI(wave->data[j]);
-    }
+    wave->putWaveData(w);
   }
 
   /// SAMPLE

src/engine/wavetable.cpp

@@ -1,3 +1,45 @@
+#include "engine.h"
 #include "wavetable.h"
+#include "../ta-log.h"
 
-// ???
+void DivWavetable::putWaveData(SafeWriter* w) {
+  w->write("WAVE",4);
+  w->writeI(0);
+
+  w->writeC(0); // name
+  w->writeI(len);
+  w->writeI(min);
+  w->writeI(max);
+  for (int j=0; j<len; j++) {
+    w->writeI(data[j]);
+  }
+}
+
+bool DivWavetable::save(const char* path) {
+  SafeWriter* w=new SafeWriter();
+  w->init();
+
+  // write magic
+  w->write("-Furnace waveta-",16);
+
+  // write version
+  w->writeS(DIV_ENGINE_VERSION);
+
+  // reserved
+  w->writeS(0);
+
+  putWaveData(w);
+
+  FILE* outFile=fopen(path,"wb");
+  if (outFile==NULL) {
+    logE("could not save wavetable: %s!\n",strerror(errno));
+    w->finish();
+    return false;
+  }
+  if (fwrite(w->getFinalBuf(),1,w->size(),outFile)!=w->size()) {
+    logW("did not write entire wavetable!\n");
+  }
+  fclose(outFile);
+  w->finish();
+  return true;
+}