GlueGen (Compile Time): Add 'CStruct' Annotation Processor (APT) to 'gluegen' C Structs on-the-fly (2-pass actually).

Convenient annotation processing (APT) hooked to 'javac' (1.6) via gluegen.jar META-INF
service provider 'javax.annotation.processing.Processor' -> 'com.jogamp.gluegen.structgen.CStructAnnotationProcessor'.

Am implicit APT / JAVAC would be possible, however - to have a proper process
the unit test utilizes an explicit 2 pass run:

        <!-- Annotation Processor Only - First -->
        <javac destdir="${build_t.java}">
            <classpath refid="junit.compile.classpath"/>
            <compilerarg value="-proc:only"/>
            <compilerarg value="-J-Djogamp.gluegen.structgen.debug"/>
            <compilerarg value="-J-Djogamp.gluegen.structgen.output=${build_t.gen}/classes"/>
            <src path="${test.base.dir}/com/jogamp/gluegen/test/junit/structgen"/>
        </javac>

        <!-- Javac Only - Second -->
        <javac destdir="${build_t.java}">
            <classpath refid="junit.compile.classpath"/>
            <compilerarg value="-proc:none"/>
            <src path="${test.base.dir}"/>
            <src path="${build_t.gen}" />
        </javac>

Original code from Michael Bien's 'superglue' git://github.com/mbien/superglue.git,
finally merged to GlueGen (as once intended).

Note: The APT javac pass requires to use 'gluegen.jar' instead of 'gluegen-rt.jar' !
      The 2-pass process also alows using the runtime gluegen-rt.jar and hence ensures
      clean namespace check at compilation.

7 files changed, 392 insertions, 7 deletions

diff --git a/src/java/com/jogamp/common/util/PropertyAccess.java b/src/java/com/jogamp/common/util/PropertyAccess.java
index dde6b50..1a4bc7e 100644
--- a/src/java/com/jogamp/common/util/PropertyAccess.java
+++ b/src/java/com/jogamp/common/util/PropertyAccess.java
@@ -156,6 +156,17 @@ public class PropertyAccess {
     return s;
   }
   
+  /** See {@link #getProperty(String, boolean)}, additionally allows a <code>defaultValue</code> if property value is <code>null</code>. */
+  public static final String getProperty(final String propertyKey, final boolean jnlpAlias, String defaultValue) 
+      throws SecurityException, NullPointerException, IllegalArgumentException {
+    final String s = PropertyAccess.getProperty(propertyKey, jnlpAlias);
+    if( null != s ) {
+        return s;
+    } else {
+        return defaultValue;
+    }
+  }
+  
   private static final String getTrustedPropKey(final String propertyKey) {
     return AccessController.doPrivileged(new PrivilegedAction<String>() {
         public String run() {
diff --git a/src/java/com/jogamp/gluegen/JavaEmitter.java b/src/java/com/jogamp/gluegen/JavaEmitter.java
index 1a6c313..18b2636 100644
--- a/src/java/com/jogamp/gluegen/JavaEmitter.java
+++ b/src/java/com/jogamp/gluegen/JavaEmitter.java
@@ -811,14 +811,14 @@ public class JavaEmitter implements GlueEmitter {
       writer = openFile(
         cfg.javaOutputDir() + File.separator +
         CodeGenUtils.packageAsPath(structClassPkg) +
-        File.separator + containingTypeName + ".java");
+        File.separator + containingTypeName + ".java", containingTypeName);
       CodeGenUtils.emitAutogeneratedWarning(writer, this);
       if (needsNativeCode) {
         String nRoot = cfg.nativeOutputDir();
         if (cfg.nativeOutputUsesJavaHierarchy()) {
           nRoot += File.separator + CodeGenUtils.packageAsPath(cfg.packageName());
         }
-        newWriter = openFile(nRoot + File.separator + containingTypeName + "_JNI.c");
+        newWriter = openFile(nRoot + File.separator + containingTypeName + "_JNI.c", containingTypeName);
         CodeGenUtils.emitAutogeneratedWarning(newWriter, this);
         emitCHeader(newWriter, containingTypeName);
       }
@@ -1379,7 +1379,13 @@ public class JavaEmitter implements GlueEmitter {
     return layout;
   }
 
-  protected PrintWriter openFile(String filename) throws IOException {
+  /**
+   * @param filename the class's full filename to open w/ write access
+   * @param simpleClassName the simple class name, i.e. w/o package name
+   * @return a {@link PrintWriter} instance to write the class source file
+   * @throws IOException
+   */
+  protected PrintWriter openFile(String filename, String simpleClassName) throws IOException {
     //System.out.println("Trying to open: " + filename);
     File file = new File(filename);
     String parentDir = file.getParent();
@@ -1432,13 +1438,13 @@ public class JavaEmitter implements GlueEmitter {
     }
 
     if (cfg.allStatic() || cfg.emitInterface()) {
-      javaWriter = openFile(jRoot + File.separator + cfg.className() + ".java");
+      javaWriter = openFile(jRoot + File.separator + cfg.className() + ".java", cfg.className());
     }
     if (!cfg.allStatic() && cfg.emitImpl()) {
-      javaImplWriter = openFile(jImplRoot + File.separator + cfg.implClassName() + ".java");
+      javaImplWriter = openFile(jImplRoot + File.separator + cfg.implClassName() + ".java", cfg.implClassName());
     }
     if (cfg.emitImpl()) {
-      cWriter = openFile(nRoot + File.separator + cfg.implClassName() + "_JNI.c");
+      cWriter = openFile(nRoot + File.separator + cfg.implClassName() + "_JNI.c", cfg.implClassName());
     }
 
     if (javaWriter != null) {
diff --git a/src/java/com/jogamp/gluegen/procaddress/ProcAddressEmitter.java b/src/java/com/jogamp/gluegen/procaddress/ProcAddressEmitter.java
index ba884d0..82434cf 100644
--- a/src/java/com/jogamp/gluegen/procaddress/ProcAddressEmitter.java
+++ b/src/java/com/jogamp/gluegen/procaddress/ProcAddressEmitter.java
@@ -285,7 +285,7 @@ public class ProcAddressEmitter extends JavaEmitter {
         }
         String jImplRoot = getJavaOutputDir() + File.separator + CodeGenUtils.packageAsPath(implPackageName);
 
-        tableWriter = openFile(jImplRoot + File.separator + tableClassName + ".java");
+        tableWriter = openFile(jImplRoot + File.separator + tableClassName + ".java", tableClassName);
         emittedTableEntries = new HashSet<String>();
 
         CodeGenUtils.emitAutogeneratedWarning(tableWriter, this);
diff --git a/src/java/com/jogamp/gluegen/structgen/CStruct.java b/src/java/com/jogamp/gluegen/structgen/CStruct.java
new file mode 100644
index 0000000..9d57196
--- /dev/null
+++ b/src/java/com/jogamp/gluegen/structgen/CStruct.java
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2010, Michael Bien. All rights reserved.
+ * Copyright (c) 2013 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Michael Bien nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL Michael Bien BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package com.jogamp.gluegen.structgen;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ *
+ * @author Michael Bien
+ * @author Sven Gothel, et.al.
+ */
+@Target(value = {ElementType.FIELD, ElementType.LOCAL_VARIABLE})
+@Retention(value = RetentionPolicy.SOURCE)
+public @interface CStruct {
+
+    /**
+     * Relative path to the header file.
+     */
+    String header();
+
+    /**
+     * The name of the struct.
+     */
+    String name() default "_default_";
+}
diff --git a/src/java/com/jogamp/gluegen/structgen/CStructAnnotationProcessor.java b/src/java/com/jogamp/gluegen/structgen/CStructAnnotationProcessor.java
new file mode 100644
index 0000000..fef8545
--- /dev/null
+++ b/src/java/com/jogamp/gluegen/structgen/CStructAnnotationProcessor.java
@@ -0,0 +1,240 @@
+/*
+ * Copyright (c) 2010, Michael Bien. All rights reserved.
+ * Copyright (c) 2013 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Michael Bien nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL Michael Bien BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package com.jogamp.gluegen.structgen;
+
+import com.jogamp.common.util.PropertyAccess;
+import com.jogamp.gluegen.GlueGen;
+import com.jogamp.gluegen.JavaEmitter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.util.HashSet;
+import java.util.Set;
+import javax.annotation.processing.AbstractProcessor;
+import javax.annotation.processing.Filer;
+import javax.annotation.processing.Messager;
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.annotation.processing.RoundEnvironment;
+import javax.annotation.processing.SupportedAnnotationTypes;
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.lang.model.SourceVersion;
+import javax.lang.model.element.Element;
+import javax.lang.model.element.TypeElement;
+import javax.lang.model.util.Elements;
+import javax.tools.Diagnostic.Kind;
+import javax.tools.FileObject;
+import javax.tools.StandardLocation;
+
+import jogamp.common.Debug;
+
+import static java.io.File.*;
+
+/**
+ * <p>
+ * If the <i>header file</i> is absolute, the <i>root path</i> is the parent folder of the folder containing the package source, i.e.:
+ * <pre>
+ *  Header: /gluegen/src/junit/com/jogamp/test/structgen/TestStruct01.h
+ *  Root:   /gluegen/src/junit/..
+ *  Root:   /gluegen/src
+ * </pre>
+ * Otherwise the <i>user.dir</i> is being used as the <i>root path</i>
+ * and the relative <i>header file</i> is appended to it.
+ * </p>
+ * The property <code>jogamp.gluegen.structgen.output</code> allows setting a default <i>outputPath</i>
+ * for the generated sources, if the {@link ProcessingEnvironment}'s <code>structgen.output</code> option is not set.
+ * <p>
+ * If the <i>outputPath</i> is relative, it is appended to the <i>root path</i>,
+ * otherwise it is taken as-is.
+ * </p>
+ * <p>
+ * User can enable DEBUG while defining property <code>jogamp.gluegen.structgen.debug</code>.
+ * </p>
+ * 
+ * @author Michael Bien
+ * @author Sven Gothel, et.al.
+ */
+@SupportedAnnotationTypes(value = {"com.jogamp.gluegen.structgen.CStruct"})
+@SupportedSourceVersion(SourceVersion.RELEASE_6)
+public class CStructAnnotationProcessor extends AbstractProcessor {
+    private static final boolean DEBUG = Debug.isPropertyDefined("jogamp.gluegen.structgen.debug", true);
+    private static final String DEFAULT = "_default_";
+    
+    private static final String STRUCTGENOUTPUT_OPTION = "structgen.output";
+    private static final String STRUCTGENOUTPUT = PropertyAccess.getProperty("jogamp.gluegen."+STRUCTGENOUTPUT_OPTION, true, "gensrc");
+    
+    private Filer filer;
+    private Messager messager;
+    private Elements eltUtils;
+    private String outputPath;
+
+    private final static Set<String> generatedStructs = new HashSet<String>();
+
+
+    @Override
+    public void init(ProcessingEnvironment processingEnv) {
+        super.init(processingEnv);
+
+        filer = processingEnv.getFiler();
+        messager = processingEnv.getMessager();
+        eltUtils = processingEnv.getElementUtils();
+
+        outputPath = processingEnv.getOptions().get(STRUCTGENOUTPUT_OPTION);
+        outputPath = outputPath == null ? STRUCTGENOUTPUT : outputPath;
+    }
+
+    @Override
+    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment env) {
+
+        Set<? extends Element> elements = env.getElementsAnnotatedWith(CStruct.class);
+
+        for (Element element : elements) {
+
+            final String packageName = eltUtils.getPackageOf(element).toString();
+            final String user_dir = System.getProperty("user.dir");
+
+            try {
+                final CStruct struct = element.getAnnotation(CStruct.class);
+                final String headerRelPath = struct.header();
+                final FileObject header;
+                final File headerFileRel;
+                {
+                    FileObject h = filer.getResource(StandardLocation.SOURCE_PATH, packageName, headerRelPath);
+                    File f = new File( h.toUri().getPath() ); // URI is incomplete (no scheme), hence use path only!
+                    if( !f.exists() ) {
+                        h = filer.getResource(StandardLocation.SOURCE_PATH, "", headerRelPath);
+                        f = new File( h.toUri().getPath() ); // URI is incomplete (no scheme), hence use path only!
+                        if( !f.exists() ) {
+                            // bail out
+                            throw new RuntimeException("Could not locate header "+headerRelPath+", package "+packageName);
+                        }
+                    }
+                    header = h;
+                    headerFileRel = f;
+                }
+                
+                final boolean headerFileRelIsAbsolute = headerFileRel.isAbsolute();  
+
+                final String root;
+                final File headerFile;
+                if( headerFileRelIsAbsolute ) {
+                    headerFile = headerFileRel;
+
+                    String root0 = headerFile.getAbsolutePath();
+                    root0 = root0.substring(0, root0.length()-headerFile.getName().length()-1);
+                    root = root0.substring(0, root0.length()-packageName.length()) +"..";
+                } else {
+                    root = user_dir;
+                    headerFile = new File(root + separator + header.toUri());
+                }
+                System.err.println("CStruct: "+struct);
+                System.err.println("CStruct: package "+packageName+", header "+headerRelPath+": "+headerFile);                
+                if(DEBUG) {
+                    System.err.println("CStruct: header "+headerFileRel+", abs-path: "+headerFileRelIsAbsolute);
+                    System.err.println("CStruct: Root: "+root);
+                    System.err.println("CStruct: user.dir: "+user_dir);
+                }
+
+                generateStructBinding(element, struct, root, packageName, headerFile);
+            } catch (IOException ex) {
+                throw new RuntimeException("IOException while processing!", ex);
+            }
+        }
+        return true;
+    }
+
+    private void generateStructBinding(Element element, CStruct struct, String root, String pakage, File header) throws IOException {
+        final String declaredType = element.asType().toString();
+        final String structName   = struct.name().equals(DEFAULT) ? declaredType : struct.name();
+
+        if( generatedStructs.contains(structName) ) {
+            messager.printMessage(Kind.WARNING, "struct "+structName+" already defined elsewhere.", element);
+            return;
+        }
+        System.out.println("generating struct accessor for struct: "+structName);
+
+        generatedStructs.add(structName);
+
+        final boolean outputDirAbs;
+        {
+            final File outputDirFile = new File(outputPath);
+            outputDirAbs = outputDirFile.isAbsolute();
+        }
+        final String outputPath1 = outputDirAbs ? outputPath : root + separator + outputPath;
+        final String config = outputPath1 + separator + header.getName() + ".cfg";
+        final File configFile = new File(config);
+        if(DEBUG) {
+            System.err.println("CStruct: OutputDir: "+outputPath+", is-abs "+outputDirAbs);
+            System.err.println("CStruct: OutputPath: "+outputPath1);
+            System.err.println("CStruct: ConfigFile: "+configFile);
+        }
+
+        FileWriter writer = null;
+        try{
+            writer = new FileWriter(configFile);
+            writer.write("Package "+pakage+"\n");
+            writer.write("EmitStruct "+structName+"\n");
+            if(!struct.name().equals(DEFAULT)) {
+                writer.write("RenameJavaType " + struct.name()+" " + declaredType +"\n");
+            }
+        } finally {
+            if( null != writer ) {
+                writer.close();
+            }
+        }
+
+        // TODO: Handle exceptions .. suppressed by Gluegen.main(..) ?
+        GlueGen.main(
+                //                "-I"+path+"/build/",
+                "-O" + outputPath1,
+                "-E" + AnnotationProcessorJavaStructEmitter.class.getName(),
+                "-C" + config,
+                header.getPath());
+
+        configFile.delete();
+    }
+
+    public static class AnnotationProcessorJavaStructEmitter extends JavaEmitter {
+
+        @Override
+        protected PrintWriter openFile(String filename, String simpleClassName) throws IOException {
+
+            // look for recursive generated structs... keep it DRY
+            if( !simpleClassName.endsWith("32") &&
+                !simpleClassName.endsWith("64") ) {
+
+                System.out.println("generating -> " + simpleClassName);
+                generatedStructs.add(simpleClassName);
+            }
+
+            return super.openFile(filename, simpleClassName);
+        }
+
+    }
+
+}
diff --git a/src/junit/com/jogamp/gluegen/test/junit/structgen/TestStruct01.h b/src/junit/com/jogamp/gluegen/test/junit/structgen/TestStruct01.h
new file mode 100644
index 0000000..6ad77d9
--- /dev/null
+++ b/src/junit/com/jogamp/gluegen/test/junit/structgen/TestStruct01.h
@@ -0,0 +1,24 @@
+//
+// TestStruct01.h
+//
+
+typedef struct {
+    float x, y, z;
+} Vec3f;
+
+typedef struct {
+    Vec3f orig, dir;
+} Camera;
+
+typedef struct {
+    unsigned int width, height;
+    int superSamplingSize;
+    int actvateFastRendering;
+    int enableShadow;
+
+    unsigned int maxIterations;
+    float epsilon;
+    float mu[4];
+    float light[3];
+    Camera camera;
+} RenderingConfig;
diff --git a/src/junit/com/jogamp/gluegen/test/junit/structgen/TestStructGen01.java b/src/junit/com/jogamp/gluegen/test/junit/structgen/TestStructGen01.java
new file mode 100644
index 0000000..444593d
--- /dev/null
+++ b/src/junit/com/jogamp/gluegen/test/junit/structgen/TestStructGen01.java
@@ -0,0 +1,51 @@
+package com.jogamp.gluegen.test.junit.structgen;
+
+import com.jogamp.gluegen.structgen.CStruct;
+import com.jogamp.junit.util.JunitTracer;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestStructGen01 extends JunitTracer {
+
+    // APT is only triggered for fields,
+    // hence we use unused fields in this unit test!
+    
+    // @CStruct(name="RenderingConfig", header="TestStruct01.h")
+    // MyRenderingConfig config;
+    
+    @CStruct(header="TestStruct01.h")
+    RenderingConfig config0;
+    
+    @Test
+    public void test01() {
+        RenderingConfig config = RenderingConfig.create();
+        Vec3f dir = config.getCamera().getDir();
+        dir.setX(0.5f);
+        dir.setY(0.6f);
+        dir.setZ(0.7f);
+        Vec3f dir2 = Vec3f.create(dir.getBuffer());
+        Assert.assertEquals(dir.getX(), dir2.getX(), 0.0001f);
+        Assert.assertEquals(dir.getY(), dir2.getY(), 0.0001f);
+        Assert.assertEquals(dir.getZ(), dir2.getZ(), 0.0001f);
+    }
+
+    @Test
+    public void test02() {
+        Camera cam = Camera.create();
+        Vec3f cam_dir = cam.getDir();
+        Vec3f cam_orig = cam.getOrig();
+        cam_dir.setX(1);
+        cam_dir.setY(2);
+        cam_dir.setZ(3);
+        cam_orig.setX(0);
+        cam_orig.setY(1);
+        cam_orig.setZ(2);
+    }
+    
+    public static void main(String args[]) {
+        String tstname = TestStructGen01.class.getName();
+        org.junit.runner.JUnitCore.main(tstname);
+    }
+    
+}