GlueGen Struct [1]: Enhance com.jogamp.common.nio.* to serve a most native-free-code Struct-Code generation

Recfactored all NIO buffer utils to Buffers, i.e. buffer <-> address, memcpy, strnlen, etc

Buffers:
- Added copyNativeToDirectByteBuffer(..), allowing to copy a native memory slice into a direct buffer.
- Added typeNameToBufferClass(String) and sizeOfBufferElem(Class<? extends Buffer>)
- Completed slize2<Type>(..) buffer-mapping methods
- Exposure of safe getDirectByteBuffer(..) w/ null-check (package private)

Added NativeBuffer.storeDirectAddress(..), allowing to write the array address into a native buffer (struct, etc),
allowing to referencing the ElementBuffer (linear array of elements) and PointerBuffer (array of pointer).
Hint: This can be read via PointerBuffer.wrap(..).get(0)

Added ElementBuffer (a NativeBuffer) mapping an array of elements,
completing native abstraction next to PointerBuffer (array of pointer).

ElementBuffer can dereference an existing element-array by native address via ElementBuffer.derefPointer(..).
Views of its content can be directly accessed via ElementBuffer.slice(..).

+++

These utilities and buffer abstractions will allow to reuse code and simplify the GlueGen struct get/set implementations
and help to reduce native code injection.

2 files changed, 30 insertions, 14 deletions

diff --git a/src/native/common/Buffers.c b/src/native/common/Buffers.c
new file mode 100644
index 0000000..0898e6b
--- /dev/null
+++ b/src/native/common/Buffers.c
@@ -0,0 +1,30 @@
+
+#include <jni.h>
+
+#include <assert.h>
+#include <string.h>
+
+#include <gluegen_stdint.h>
+
+#include "com_jogamp_common_nio_Buffers.h"
+
+JNIEXPORT jlong JNICALL 
+Java_com_jogamp_common_nio_Buffers_getDirectBufferAddressImpl(JNIEnv *env, jclass _unused, jobject directBuffer) {
+    return ( NULL != directBuffer ) ? (jlong) (intptr_t)  (*env)->GetDirectBufferAddress(env, directBuffer) : 0L ; 
+}
+
+JNIEXPORT jobject JNICALL 
+Java_com_jogamp_common_nio_Buffers_getDirectByteBufferImpl(JNIEnv *env, jclass _unused, jlong japtr, jint jbyteCount) {
+    return ( 0 != japtr && 0 < jbyteCount ) ? (*env)->NewDirectByteBuffer(env, (void *)(intptr_t)japtr, jbyteCount) : NULL;
+}
+
+JNIEXPORT jint JNICALL 
+Java_com_jogamp_common_nio_Buffers_strnlenImpl(JNIEnv *env, jclass _unused, jlong jcstrptr, jint jmaxlen) {
+    return ( 0 != jcstrptr && 0 < jmaxlen ) ? strnlen((const char *)(void *)(intptr_t)jcstrptr, jmaxlen) : 0;
+}
+
+JNIEXPORT jlong JNICALL 
+Java_com_jogamp_common_nio_Buffers_memcpyImpl(JNIEnv *env, jclass _unused, jlong jdest, jlong jsrc, jlong jlen) {
+    return ( 0 != jdest && 0 != jsrc && 0 < jlen ) ? memcpy((void *)(intptr_t)jdest, (void *)(intptr_t)jsrc, (size_t)jlen) : jdest;
+}
+
diff --git a/src/native/common/PointerBuffer.c b/src/native/common/PointerBuffer.c
deleted file mode 100644
index f3e25d3..0000000
--- a/src/native/common/PointerBuffer.c
+++ /dev/null
@@ -1,14 +0,0 @@
-
-#include <jni.h>
-
-#include <assert.h>
-
-#include <gluegen_stdint.h>
-
-#include "com_jogamp_common_nio_PointerBuffer.h"
-
-JNIEXPORT jlong JNICALL 
-Java_com_jogamp_common_nio_PointerBuffer_getDirectBufferAddressImpl(JNIEnv *env, jclass _unused, jobject directBuffer) {
-    return ( NULL != directBuffer ) ? (jlong) (intptr_t)  (*env)->GetDirectBufferAddress(env, directBuffer) : 0L ; 
-}
-