FIX StructAccessor / JavaEmitter's struct-emitter: Using byte offsets

Problem:
    typedef struct {
        int8_t bits1;  // +1       -   0
                       // +3 (p32)
        int32_t id;    // +4       -   4
        int8_t bits2;  // +1       -   8
                       // +3 (p32) -
        int64_t long0; // +8       -  12

    "longBuffer.get(<type-sized index>)" is invalid,
    but "byteBuffer.getLong(<byte index>)" must be done.

    The actual impl. doesn't matter, hence dropping the other nio type mappings is good.

FIXES 32bit unit test, works well (static) on 32/64 bit (unix).

TODO: Respect diff alignment for OS/ARCH either by offset tables for all, or runtime computing.

2 files changed, 90 insertions, 167 deletions

diff --git a/src/java/com/jogamp/common/nio/StructAccessor.java b/src/java/com/jogamp/common/nio/StructAccessor.java
index c641d79..0f88551 100644
--- a/src/java/com/jogamp/common/nio/StructAccessor.java
+++ b/src/java/com/jogamp/common/nio/StructAccessor.java
@@ -43,17 +43,10 @@ import java.nio.*;
 
 /**
  * @author Kenneth Russel
- * @author Michael Bien
  */
 public class StructAccessor {
 
     private ByteBuffer bb;
-    private FloatBuffer fb;
-    private IntBuffer ib;
-    private ShortBuffer sb;
-    private CharBuffer cb;
-    private DoubleBuffer db;
-    private LongBuffer lb;
 
     public StructAccessor(ByteBuffer bb) {
         // Setting of byte order is concession to native code which needs
@@ -74,202 +67,161 @@ public class StructAccessor {
     public ByteBuffer slice(int byteOffset, int byteLength) {
         bb.position(byteOffset);
         bb.limit(byteOffset + byteLength);
-        ByteBuffer newBuf = bb.slice();
+        final ByteBuffer newBuf = bb.slice().order(bb.order()); // slice and duplicate may change byte order
         bb.position(0);
         bb.limit(bb.capacity());
         return newBuf;
     }
 
-    /** Retrieves the byte at the specified slot (byte offset). */
-    public byte getByteAt(int slot) {
-        return bb.get(slot);
+    /** Retrieves the byte at the specified byteOffset. */
+    public byte getByteAt(int byteOffset) {
+        return bb.get(byteOffset);
     }
 
-    /** Puts a byte at the specified slot (byte offset). */
-    public void setByteAt(int slot, byte v) {
-        bb.put(slot, v);
+    /** Puts a byte at the specified byteOffset. */
+    public void setByteAt(int byteOffset, byte v) {
+        bb.put(byteOffset, v);
     }
 
-    /** Retrieves the char at the specified slot (2-byte offset). */
-    public char getCharAt(int slot) {
-        return charBuffer().get(slot);
+    /** Retrieves the char at the specified byteOffset. */
+    public char getCharAt(int byteOffset) {
+        return bb.getChar(byteOffset);
     }
 
-    /** Puts a char at the specified slot (2-byte offset). */
-    public void setCharAt(int slot, char v) {
-        charBuffer().put(slot, v);
+    /** Puts a char at the specified byteOffset. */
+    public void setCharAt(int byteOffset, char v) {
+        bb.putChar(byteOffset, v);
     }
 
-    /** Retrieves the double at the specified slot (8-byte offset). */
-    public double getDoubleAt(int slot) {
-        return doubleBuffer().get(slot);
+    /** Retrieves the short at the specified byteOffset. */
+    public short getShortAt(int byteOffset) {
+        return bb.getShort(byteOffset);
     }
 
-    /** Puts a double at the specified slot (8-byte offset). */
-    public void setDoubleAt(int slot, double v) {
-        doubleBuffer().put(slot, v);
+    /** Puts a short at the specified byteOffset. */
+    public void setShortAt(int byteOffset, short v) {
+        bb.putShort(byteOffset, v);
     }
 
-    /** Retrieves the float at the specified slot (4-byte offset). */
-    public float getFloatAt(int slot) {
-        return floatBuffer().get(slot);
+    /** Retrieves the int at the specified byteOffset. */
+    public int getIntAt(int byteOffset) {
+        return bb.getInt(byteOffset);
     }
 
-    /** Puts a float at the specified slot (4-byte offset). */
-    public void setFloatAt(int slot, float v) {
-        floatBuffer().put(slot, v);
+    /** Puts a int at the specified byteOffset. */
+    public void setIntAt(int byteOffset, int v) {
+        bb.putInt(byteOffset, v);
     }
 
-    /** Retrieves the int at the specified slot (4-byte offset). */
-    public int getIntAt(int slot) {
-        return intBuffer().get(slot);
+    /** Retrieves the float at the specified byteOffset. */
+    public float getFloatAt(int byteOffset) {
+        return bb.getFloat(byteOffset);
     }
 
-    /** Puts a int at the specified slot (4-byte offset). */
-    public void setIntAt(int slot, int v) {
-        intBuffer().put(slot, v);
+    /** Puts a float at the specified byteOffset. */
+    public void setFloatAt(int byteOffset, float v) {
+        bb.putFloat(byteOffset, v);
     }
 
-    /** Retrieves the short at the specified slot (2-byte offset). */
-    public short getShortAt(int slot) {
-        return shortBuffer().get(slot);
+    /** Retrieves the double at the specified byteOffset. */
+    public double getDoubleAt(int byteOffset) {
+        return bb.getDouble(byteOffset);
     }
 
-    /** Puts a short at the specified slot (2-byte offset). */
-    public void setShortAt(int slot, short v) {
-        shortBuffer().put(slot, v);
+    /** Puts a double at the specified byteOffset. */
+    public void setDoubleAt(int byteOffset, double v) {
+        bb.putDouble(byteOffset, v);
     }
 
-    public void setBytesAt(int slot, byte[] v) {
-        for (int i = 0; i < v.length; i++) {
-            bb.put(slot++, v[i]);
-        }
+    /**
+     * Retrieves the long at the specified byteOffset.
+     */
+    public long getLongAt(int byteOffset) {
+        return bb.getLong(byteOffset);
     }
 
-    public byte[] getBytesAt(int slot, byte[] v) {
-        for (int i = 0; i < v.length; i++) {
-            v[i] = bb.get(slot++);
-        }
-        return v;
+    /**
+     * Puts a long at the specified byteOffset.
+     */
+    public void setLongAt(int byteOffset, long v) {
+        bb.putLong(byteOffset, v);
     }
-
-    public void setCharsAt(int slot, char[] v) {
+    
+    public void setBytesAt(int byteOffset, byte[] v) {
         for (int i = 0; i < v.length; i++) {
-            charBuffer().put(slot++, v[i]);
+            bb.put(byteOffset++, v[i]);
         }
     }
 
-    public char[] getCharsAt(int slot, char[] v) {
+    public byte[] getBytesAt(int byteOffset, byte[] v) {
         for (int i = 0; i < v.length; i++) {
-            v[i] = charBuffer().get(slot++);
+            v[i] = bb.get(byteOffset++);
         }
         return v;
     }
 
-    public void setIntsAt(int slot, int[] v) {
-        for (int i = 0; i < v.length; i++) {
-            intBuffer().put(slot++, v[i]);
+    public void setCharsAt(int byteOffset, char[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=2) {
+            bb.putChar(byteOffset, v[i]);
         }
     }
 
-    public int[] getIntsAt(int slot, int[] v) {
-        for (int i = 0; i < v.length; i++) {
-            v[i] = intBuffer().get(slot++);
+    public char[] getCharsAt(int byteOffset, char[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=2) {
+            v[i] = bb.getChar(byteOffset);
         }
         return v;
     }
 
-    public void setFloatsAt(int slot, float[] v) {
-        for (int i = 0; i < v.length; i++) {
-            floatBuffer().put(slot++, v[i]);
+    public void setIntsAt(int byteOffset, int[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=4) {
+            bb.putInt(byteOffset, v[i]);
         }
     }
 
-    public float[] getFloatsAt(int slot, float[] v) {
-        for (int i = 0; i < v.length; i++) {
-            v[i] = floatBuffer().get(slot++);
+    public int[] getIntsAt(int byteOffset, int[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=4) {
+            v[i] = bb.getInt(byteOffset);
         }
         return v;
     }
 
-    /**
-     * Puts a double at the specified slot (8-byte offset).
-     * May throw an {@link UnsupportedOperationException}
-     */
-    public void setDoublesAt(int slot, double[] v) {
-        for (int i = 0; i < v.length; i++) {
-            doubleBuffer().put(slot++, v[i]);
+    public void setFloatsAt(int byteOffset, float[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=4) {
+            bb.putFloat(byteOffset, v[i]);
         }
     }
 
-    /**
-     * Retrieves the long at the specified slot (8-byte offset).
-     * May throw an {@link UnsupportedOperationException}
-     */
-    public double[] getDoublesAt(int slot, double[] v) {
-        for (int i = 0; i < v.length; i++) {
-            v[i] = doubleBuffer().get(slot++);
+    public float[] getFloatsAt(int byteOffset, float[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=4) {
+            v[i] = bb.getFloat(byteOffset);
         }
         return v;
     }
 
-    /**
-     * Retrieves the long at the specified slot (8-byte offset).
-     */
-    public long getLongAt(int slot) {
-        return longBuffer().get(slot);
-    }
-
-    /**
-     * Puts a long at the specified slot (8-byte offset).
-     */
-    public void setLongAt(int slot, long v) {
-        longBuffer().put(slot, v);
-    }
-
-    //----------------------------------------------------------------------
-    // Internals only below this point
-    //
-
-    private final FloatBuffer floatBuffer() {
-        if (fb == null) {
-            fb = bb.asFloatBuffer();
+    public void setDoublesAt(int byteOffset, double[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=8) {
+            bb.putDouble(byteOffset, v[i]);
         }
-        return fb;
     }
 
-    private final IntBuffer intBuffer() {
-        if (ib == null) {
-            ib = bb.asIntBuffer();
+    public double[] getDoublesAt(int byteOffset, double[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=8) {
+            v[i] = bb.getDouble(byteOffset);
         }
-        return ib;
-    }
-
-    private final ShortBuffer shortBuffer() {
-        if (sb == null) {
-            sb = bb.asShortBuffer();
-        }
-        return sb;
-    }
-
-    private final LongBuffer longBuffer() {
-        if (lb == null) {
-            lb = bb.asLongBuffer();
-        }
-        return lb;
+        return v;
     }
 
-    private final DoubleBuffer doubleBuffer() {
-        if (db == null) {
-            db = bb.asDoubleBuffer();
+    public void setLongsAt(int byteOffset, long[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=8) {
+            bb.putLong(byteOffset, v[i]);
         }
-        return db;
     }
 
-    private final CharBuffer charBuffer() {
-        if (cb == null) {
-            cb = bb.asCharBuffer();
+    public long[] getLongsAt(int byteOffset, long[] v) {
+        for (int i = 0; i < v.length; i++, byteOffset+=8) {
+            v[i] = bb.getLong(byteOffset);
         }
-        return cb;
+        return v;
     }
 }
diff --git a/src/java/com/jogamp/gluegen/JavaEmitter.java b/src/java/com/jogamp/gluegen/JavaEmitter.java
index 770db38..dfa7594 100644
--- a/src/java/com/jogamp/gluegen/JavaEmitter.java
+++ b/src/java/com/jogamp/gluegen/JavaEmitter.java
@@ -1062,10 +1062,7 @@ public class JavaEmitter implements GlueEmitter {
             String paramType = typeToJavaType(baseElementType, false, extMachDesc).getName();
             String capitalized = capitalizeString(fieldName);
 
-            int slot = -1;
-            if(!doBaseClass) {
-              slot = slot(fieldType, (int) field.getOffset(intMachDesc), intMachDesc);
-            }
+            final int byteOffset = doBaseClass ? -1 : (int) field.getOffset(intMachDesc);
 
             // Setter
             writer.println();
@@ -1074,7 +1071,7 @@ public class JavaEmitter implements GlueEmitter {
               writer.println(";");
             } else {
               writer.println(" {");
-              writer.print  ("    accessor.set" + capitalizeString(paramType) + "sAt(" + slot + ", ");
+              writer.print  ("    accessor.set" + capitalizeString(paramType) + "sAt(" + byteOffset + ", ");
               writer.println("val);");
               writer.println("    return this;");
               writer.println("  }");
@@ -1087,7 +1084,7 @@ public class JavaEmitter implements GlueEmitter {
             } else {
               writer.println(" {");
               writer.print  ("    return ");
-              writer.println("accessor.get" + capitalizeString(paramType) + "sAt(" + slot + ", new " +paramType+"["+fieldType.asArray().getLength()+"]);");
+              writer.println("accessor.get" + capitalizeString(paramType) + "sAt(" + byteOffset + ", new " +paramType+"["+fieldType.asArray().getLength()+"]);");
               writer.println("  }");
             }
 
@@ -1123,10 +1120,7 @@ public class JavaEmitter implements GlueEmitter {
             if (!doBaseClass) {
               capitalized = capitalizeString(internalJavaTypeName);
             }
-            int slot = -1;
-            if (!doBaseClass) {
-              slot = slot(fieldType, (int) field.getOffset(intMachDesc), intMachDesc);
-            }
+            final int byteOffset = doBaseClass ? -1 : (int) field.getOffset(intMachDesc);
             writer.println();
             String capitalizedFieldName = capitalizeString(fieldName);
             // Setter
@@ -1135,7 +1129,7 @@ public class JavaEmitter implements GlueEmitter {
               writer.println(";");
             } else {
               writer.println(" {");
-              writer.print  ("    accessor.set" + capitalized + "At(" + slot + ", ");
+              writer.print  ("    accessor.set" + capitalized + "At(" + byteOffset + ", ");
               if (!externalJavaTypeName.equals(internalJavaTypeName)) {
                 writer.print("(" + internalJavaTypeName + ") ");
               }
@@ -1154,7 +1148,7 @@ public class JavaEmitter implements GlueEmitter {
               if (!externalJavaTypeName.equals(internalJavaTypeName)) {
                 writer.print("(" + externalJavaTypeName + ") ");
               }
-              writer.println("accessor.get" + capitalized + "At(" + slot + ");");
+              writer.println("accessor.get" + capitalized + "At(" + byteOffset + ");");
               writer.println("  }");
             }
           } else {
@@ -1408,29 +1402,6 @@ public class JavaEmitter implements GlueEmitter {
             (c == Long.TYPE));
   }
 
-  private int slot(Type t, int byteOffset, MachineDescription curMachDesc) {
-    if (t.isInt()) {
-      final int tsz = (int) t.getSize(curMachDesc);
-      switch (tsz) {
-       case 1:
-       case 2:
-       case 4:
-       case 8:  return byteOffset / tsz;
-       default: throw new RuntimeException("Illegal type");
-      }
-    } else if (t.isFloat()) {
-      return byteOffset / 4;
-    } else if (t.isDouble()) {
-      return byteOffset / 8;
-    } else if (t.isPointer()) {
-      return byteOffset / curMachDesc.pointerSizeInBytes();
-    } else if (t.isArray()) {
-      return slot(t.asArray().getBaseElementType(), byteOffset, curMachDesc);
-    } else {
-      throw new RuntimeException("Illegal type " + t);
-    }
-  }
-
   private StructLayout getLayout() {
     if (layout == null) {
       layout = StructLayout.create(0);