GlueGen: Add support for 'compound call-by-value', i.e. passing and returning struct instance

'compound call-by-value' is not efficient.

However, to allow mapping APIs utilizing passing small structs
as arguments and return values - this feature has been added.

+++

To return the struct value, native code needs to
allocate a NIO ByteBuffer and copy the data.
The stack return value can be dismissed afterwards and the
NIO buffer is returned.

We include this functionality for all generated [impl] classes,
native method:
  'static jobject JVMUtil_NewDirectByteBufferCopy(JNIEnv *env, void * source_address, jlong capacity)'

  (See: 'JavaEmitter.initClassAccessCode')

Since this code requires knowledge of java classes and methods,
for which a reference needs to be acquired, a static initialization method
has been introduced for all generated [impl] classes:
  'private static native boolean initializeImpl();'

Per default the this method will be called in the new
static initializer block of the class,
which can be supressed via the configuration element:
   'ManualStaticInit <class-name>'

'ManualStaticInit' can be used to issue the 'initializeImpl()'
call in a custom static initializer written by the user.

However, at the time 'initializeImpl()' gets called
the JNI native library must have been loaded, of course!

+++

- See tag: // FIXME: Compound call-by-value
  for code changes and validation of completeness

Trigger for compond call-by-value in CMethodBindingEmitter is:
   !cArgType.isPointer() && javaArgType.isCompoundTypeWrapper()

Trigger for compond call-by-value in JavaEmitter is:
  t.isCompound()

+++

Further more we do tolerate 'javaType.isCPrimitivePointerType()',
i.e. adding comments for offset/size and field entries,
which are all NOP.

This allows to utilize the remaining fields of the native structure.

+++

Tests: Added call-by-value to test1.[ch] binding test!

1 files changed, 18 insertions, 0 deletions

diff --git a/src/java/com/jogamp/gluegen/JavaConfiguration.java b/src/java/com/jogamp/gluegen/JavaConfiguration.java
index ca7eccf..7cecbce 100644
--- a/src/java/com/jogamp/gluegen/JavaConfiguration.java
+++ b/src/java/com/jogamp/gluegen/JavaConfiguration.java
@@ -156,6 +156,7 @@ public class JavaConfiguration {
     private boolean forceUseNIODirectOnly4All = false;
     private final Set<String> useNIODirectOnly = new HashSet<String>();
     private final Set<String> manuallyImplement = new HashSet<String>();
+    private final Set<String> manualStaticInit = new HashSet<String>();
     private final Map<String, List<String>> customJavaCode = new HashMap<String, List<String>>();
     private final Map<String, List<String>> classJavadoc = new HashMap<String, List<String>>();
     private final Map<String, List<String>> methodJavadoc = new HashMap<String, List<String>>();
@@ -537,6 +538,12 @@ public class JavaConfiguration {
     return manuallyImplement.contains(functionName);
   }
 
+  /** Returns true if the static initialization java code for the given class will be
+      manually implemented by the end user. */
+  public boolean manualStaticInit(String clazzName) {
+    return manualStaticInit.contains(clazzName);
+  }
+
   /** Returns a list of Strings containing user-implemented code for
       the given Java type name (not fully-qualified, only the class
       name); returns either null or an empty list if there is no
@@ -983,6 +990,8 @@ public class JavaConfiguration {
       readIgnoreField(tok, filename, lineNo);
     } else if (cmd.equalsIgnoreCase("ManuallyImplement")) {
       readManuallyImplement(tok, filename, lineNo);
+    } else if (cmd.equalsIgnoreCase("ManualStaticInit")) {
+      readManualStaticInit(tok, filename, lineNo);
     } else if (cmd.equalsIgnoreCase("CustomJavaCode")) {
       readCustomJavaCode(tok, filename, lineNo);
       // Warning: make sure delimiters are reset at the top of this loop
@@ -1283,6 +1292,15 @@ public class JavaConfiguration {
         " in file \"" + filename + "\"", e);
     }
   }
+  protected void readManualStaticInit(StringTokenizer tok, String filename, int lineNo) {
+    try {
+      String name = tok.nextToken();
+      manualStaticInit.add(name);
+    } catch (NoSuchElementException e) {
+      throw new RuntimeException("Error parsing \"ManualStaticInit\" command at line " + lineNo +
+        " in file \"" + filename + "\"", e);
+    }
+  }
 
   protected void readCustomJavaCode(StringTokenizer tok, String filename, int lineNo) {
     try {