WIP: Separate struct fields from Struct class

src/main/java/jnr/ffi/annotations/Direct.java

@@ -19,21 +19,23 @@
 package jnr.ffi.annotations;
 
 
+import jnr.ffi.struct.Struct;
+
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
 /**
- * Indicates that a {@link jnr.ffi.Struct}} parameter should be
+ * Indicates that a {@link Struct}} parameter should be
  * backed by a persistent native memory block.
  * 
  * <p>Without the {@code @Direct} annotation, the native code will allocate a
  * temporary native memory block for the parameter, and free it immediately after
  * the call.
  *
  * <p>By using {@code @Direct}, the native memory block is permanently associated
- * with the {@link jnr.ffi.Struct} instance, and will remain allocated
+ * with the {@link Struct} instance, and will remain allocated
  * for as long as the {@code Struct} instance remains strongly referenced by java code.
  *
  */

src/main/java/jnr/ffi/annotations/In.java

@@ -18,6 +18,8 @@
 
 package jnr.ffi.annotations;
 
+import jnr.ffi.struct.Struct;
+
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -27,7 +29,7 @@
  * Indicates that the parameter is an IN parameter.
  *
  * <p>When a java object is passed to a native function as a pointer
- * (for example {@link jnr.ffi.Pointer}, {@link jnr.ffi.Struct}, {@link java.nio.ByteBuffer}),
+ * (for example {@link jnr.ffi.Pointer}, {@link Struct}, {@link java.nio.ByteBuffer}),
  * then a temporary native memory block is allocated, the java data is copied to
  * the temporary memory and the address of the temporary memory is passed to the function.
  * After the function returns, the java data is automatically updated from the

src/main/java/jnr/ffi/annotations/Out.java

@@ -18,6 +18,8 @@
 
 package jnr.ffi.annotations;
 
+import jnr.ffi.struct.Struct;
+
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -27,7 +29,7 @@
  * Indicates that the parameter is an OUT parameter.
  * 
  * <p>When a java object is passed to a native function as a pointer
- * (for example {@link jnr.ffi.Pointer}, {@link jnr.ffi.Struct}, {@link java.nio.ByteBuffer}),
+ * (for example {@link jnr.ffi.Pointer}, {@link Struct}, {@link java.nio.ByteBuffer}),
  * then a temporary native memory block is allocated, the java data is copied to
  * the temporary memory and the address of the temporary memory is passed to the function.
  * After the function returns, the java data is automatically updated from the

src/main/java/jnr/ffi/provider/converters/StructArrayParameterConverter.java

@@ -19,8 +19,7 @@
 package jnr.ffi.provider.converters;
 
 import jnr.ffi.Pointer;
-import jnr.ffi.Struct;
-import jnr.ffi.annotations.LongLong;
+import jnr.ffi.struct.Struct;
 import jnr.ffi.mapper.ToNativeContext;
 import jnr.ffi.mapper.ToNativeConverter;
 import jnr.ffi.provider.DelegatingMemoryIO;

src/main/java/jnr/ffi/provider/converters/StructByReferenceFromNativeConverter.java

@@ -19,7 +19,7 @@
 package jnr.ffi.provider.converters;
 
 import jnr.ffi.Pointer;
-import jnr.ffi.Struct;
+import jnr.ffi.struct.Struct;
 import jnr.ffi.mapper.FromNativeContext;
 import jnr.ffi.mapper.FromNativeConverter;
 
@@ -28,7 +28,7 @@
 
 
 /**
- * Converts a native pointer result into a {@link jnr.ffi.Struct}
+ * Converts a native pointer result into a {@link Struct}
  */
 public class StructByReferenceFromNativeConverter implements FromNativeConverter<Struct, Pointer> {
     private final Constructor<? extends Struct> constructor;

src/main/java/jnr/ffi/provider/converters/StructByReferenceToNativeConverter.java

@@ -19,7 +19,7 @@
 package jnr.ffi.provider.converters;
 
 import jnr.ffi.Pointer;
-import jnr.ffi.Struct;
+import jnr.ffi.struct.Struct;
 import jnr.ffi.mapper.ToNativeContext;
 import jnr.ffi.mapper.ToNativeConverter;
 import jnr.ffi.provider.ParameterFlags;

src/main/java/jnr/ffi/provider/jffi/AsmStructByReferenceFromNativeConverter.java

@@ -20,7 +20,7 @@
 
 import jnr.ffi.Pointer;
 import jnr.ffi.Runtime;
-import jnr.ffi.Struct;
+import jnr.ffi.struct.Struct;
 import jnr.ffi.mapper.FromNativeContext;
 import jnr.ffi.mapper.FromNativeConverter;
 import org.objectweb.asm.ClassReader;

src/main/java/jnr/ffi/provider/jffi/ClosureTypeMapper.java

@@ -18,12 +18,11 @@
 
 package jnr.ffi.provider.jffi;
 
-import jnr.ffi.Struct;
+import jnr.ffi.struct.Struct;
 import jnr.ffi.mapper.*;
 import jnr.ffi.mapper.FromNativeType;
 import jnr.ffi.mapper.ToNativeType;
 import jnr.ffi.provider.converters.EnumConverter;
-import jnr.ffi.provider.ParameterFlags;
 import jnr.ffi.provider.converters.StringResultConverter;
 import jnr.ffi.provider.converters.StructByReferenceToNativeConverter;
 

src/main/java/jnr/ffi/provider/jffi/InvokerTypeMapper.java

@@ -20,7 +20,7 @@
 
 import jnr.ffi.NativeLong;
 import jnr.ffi.Pointer;
-import jnr.ffi.Struct;
+import jnr.ffi.struct.Struct;
 import jnr.ffi.annotations.Delegate;
 import jnr.ffi.byref.ByReference;
 import jnr.ffi.mapper.*;

src/main/java/jnr/ffi/provider/jffi/StructByReferenceResultConverterFactory.java

@@ -22,6 +22,7 @@
 import jnr.ffi.mapper.FromNativeContext;
 import jnr.ffi.mapper.FromNativeConverter;
 import jnr.ffi.provider.converters.StructByReferenceFromNativeConverter;
+import jnr.ffi.struct.Struct;
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;

src/main/java/jnr/ffi/struct/AsciiString.java

@@ -0,0 +1,10 @@
+package jnr.ffi.struct;
+
+public class AsciiString extends UTFString {
+    private Struct struct;
+
+    public AsciiString(Struct struct, int size) {
+        super(struct, size, Struct.ASCII);
+        this.struct = struct;
+    }
+}

src/main/java/jnr/ffi/struct/Field.java

@@ -0,0 +1,68 @@
+package jnr.ffi.struct;
+
+import jnr.ffi.NativeType;
+import jnr.ffi.Runtime;
+import jnr.ffi.Type;
+import jnr.ffi.TypeAlias;
+
+/**
+ * Structure field
+ */
+public abstract class Field {
+
+    private Struct.Info info;
+    private Offset offset;
+
+    protected Field(Struct struct, int size, int align, Offset offset) {
+        registerInStructure(struct, size, align, offset);
+    }
+
+    protected Field(Struct struct, int size, int align) {
+        this(struct, size, align, null);
+    }
+
+    protected Field(Struct struct, NativeType nativeType) {
+        this(struct, nativeType, null);
+    }
+
+    protected Field(Struct struct, NativeType nativeType, Offset offset) {
+        final Type type = struct.getRuntime().findType(nativeType);
+        registerInStructure(struct, type, offset);
+    }
+
+    protected Field(Struct struct, TypeAlias typeAlias) {
+        this(struct, typeAlias, null);
+    }
+
+    protected Field(Struct struct, TypeAlias typeAlias, Offset offset) {
+        Type type = struct.getRuntime().findType(typeAlias);
+        registerInStructure(struct, type, offset);
+    }
+
+    private void registerInStructure(Struct struct, Type type, Offset offset) {
+        registerInStructure(struct, type.size() * 8, type.alignment() * 8, offset);
+    }
+
+    public final jnr.ffi.Pointer getMemory() {
+        return info.getMemory();
+    }
+
+    public final Runtime getRuntime() {
+        return info.getRuntime();
+    }
+
+    protected long offset() {
+        return offset.intValue() + info.getOffset();
+    }
+
+    private void registerInStructure(Struct struct, int size, int alignment, Offset offset) {
+        info = struct.__info;
+        if (offset == null) {
+            int offsetAfterAllocation = struct.__info.addField(size, alignment);
+            this.offset = new Offset(offsetAfterAllocation);
+        } else {
+            struct.__info.addField(size, alignment, offset);
+        }
+
+    }
+}

src/main/java/jnr/ffi/struct/Offset.java

@@ -0,0 +1,24 @@
+package jnr.ffi.struct;
+
+public final class Offset extends Number {
+    private final int offset;
+    public Offset(int offset) {
+        this.offset = offset;
+    }
+    @Override
+    public int intValue() {
+        return offset;
+    }
+    @Override
+    public long longValue() {
+        return offset;
+    }
+    @Override
+    public float floatValue() {
+        return offset;
+    }
+    @Override
+    public double doubleValue() {
+        return offset;
+    }
+}

src/main/java/jnr/ffi/struct/StringField.java

@@ -0,0 +1,38 @@
+package jnr.ffi.struct;
+
+import jnr.ffi.NativeType;
+
+import java.nio.charset.Charset;
+
+abstract public class StringField extends Field {
+    protected final Charset charset;
+    protected final int length;
+
+    protected StringField(Struct struct, NativeType nativeType, int length, Charset cs) {
+        super(struct, nativeType);
+        this.length = length;
+        this.charset = cs;
+    }
+    protected StringField(Struct struct, int size, int align, int length, Charset cs) {
+        super(struct, size, align);
+        this.length = length;
+        this.charset = cs;
+    }
+    protected StringField(Struct struct, int size, int align, Offset offset, int length, Charset cs) {
+        super(struct, size, align, offset);
+        this.length = length;
+        this.charset = cs;
+    }
+    public final int length() {
+        return length;
+    }
+
+    protected abstract jnr.ffi.Pointer getStringMemory();
+    public abstract java.lang.String get();
+    public abstract void set(java.lang.String value);
+
+    @Override
+    public final java.lang.String toString() {
+        return get();
+    }
+}