Bug 1134 - ProcAddressCMethodBindingEmitter: Use available 'ProcAddrTypedef' for type validation w/ local generated variant (robustness)

ProcAddressCMethodBindingEmitter code regarding having the public 'ProcAddrTypedef' (from input header)
was simply broken, since it always used the local generated 'ProcAddrTypedef',
if 'ProcAddrTypedef' was forced. Hence the public 'ProcAddrTypedef' was ignored in most cases.

ProcAddressCMethodBindingEmitter's semantic changed from:
  needsLocalTypedef -> hasProcAddrTypedef

New Code generation:
- always generated the local 'ProcAddrTypedef'
- if hasProcAddrTypedef, use public 'ProcAddrTypedef' for return type variable
- cast local 'ProcAddrTypedef' to public 'ProcAddrTypedef',
  which renders the native compiler to validate the local and public types.

1 files changed, 35 insertions, 28 deletions

diff --git a/src/java/com/jogamp/gluegen/procaddress/ProcAddressCMethodBindingEmitter.java b/src/java/com/jogamp/gluegen/procaddress/ProcAddressCMethodBindingEmitter.java
index 09e6822..4707e57 100644
--- a/src/java/com/jogamp/gluegen/procaddress/ProcAddressCMethodBindingEmitter.java
+++ b/src/java/com/jogamp/gluegen/procaddress/ProcAddressCMethodBindingEmitter.java
@@ -50,7 +50,7 @@ import com.jogamp.gluegen.cgram.types.*;
 public class ProcAddressCMethodBindingEmitter extends CMethodBindingEmitter {
 
   private boolean callThroughProcAddress;
-  private boolean needsLocalTypedef;
+  private boolean hasProcAddrTypedef;
 
   private String localTypedefCallingConvention;
 
@@ -59,7 +59,7 @@ public class ProcAddressCMethodBindingEmitter extends CMethodBindingEmitter {
 
   public ProcAddressCMethodBindingEmitter(final CMethodBindingEmitter methodToWrap,
                                           final boolean callThroughProcAddress,
-                                          final boolean needsLocalTypedef,
+                                          final boolean hasProcAddrTypedef,
                                           final String localTypedefCallingConvention,
                                           final ProcAddressEmitter emitter) {
 
@@ -84,11 +84,6 @@ public class ProcAddressCMethodBindingEmitter extends CMethodBindingEmitter {
                 methodToWrap.getMachineDataInfo(),
                 emitter.getConfiguration()
         );
-
-        if( needsLocalTypedef && !callThroughProcAddress ) {
-            throw new IllegalArgumentException("needsLocalTypedef=true, but callThroughProcAddress=false for "+methodToWrap.toString());
-        }
-
         if (methodToWrap.getReturnValueCapacityExpression() != null) {
             setReturnValueCapacityExpression(methodToWrap.getReturnValueCapacityExpression());
         }
@@ -101,7 +96,7 @@ public class ProcAddressCMethodBindingEmitter extends CMethodBindingEmitter {
         setCommentEmitter(defaultCommentEmitter);
 
         this.callThroughProcAddress = callThroughProcAddress;
-        this.needsLocalTypedef = needsLocalTypedef;
+        this.hasProcAddrTypedef = hasProcAddrTypedef;
         this.localTypedefCallingConvention = localTypedefCallingConvention;
         this.emitter = emitter;
     }
@@ -127,25 +122,28 @@ public class ProcAddressCMethodBindingEmitter extends CMethodBindingEmitter {
             // create variable for the function pointer with the right type, and set
             // it to the value of the passed-in proc address
             final FunctionSymbol cSym = getBinding().getCSymbol();
-            String funcPointerTypedefName =
-                    emitter.getFunctionPointerTypedefName(cSym);
-
-            if (needsLocalTypedef) {
-                // We (probably) didn't get a typedef for this function
-                // pointer type in the header file; the user requested that we
-                // forcibly generate one. Here we force the emission of one.
-                final PointerType funcPtrType = new PointerType(null, cSym.getType(), 0);
-                // Just for safety, emit this name slightly differently than
-                // the mangling would otherwise produce
-                funcPointerTypedefName = "_local_" + funcPointerTypedefName;
-
-                writer.print("  typedef ");
-                writer.print(funcPtrType.toString(funcPointerTypedefName, localTypedefCallingConvention));
-                writer.println(";");
+
+            // Always emit the local typedef, based on our parsing results.
+            // In case we do have the public typedef from the original header,
+            // we use it for the local var and assign our proc-handle to it,
+            // cast to the local typedef.
+            // This allows the native C compiler to validate our types!
+            final String funcPointerTypedefBaseName = emitter.getFunctionPointerTypedefName(cSym);
+            final String funcPointerTypedefLocalName = "_local_" + funcPointerTypedefBaseName;
+            final String funcPointerTypedefName;
+            if (hasProcAddrTypedef) {
+                funcPointerTypedefName = funcPointerTypedefBaseName;
+            } else {
+                funcPointerTypedefName = funcPointerTypedefLocalName;
             }
+            final PointerType funcPtrType = new PointerType(null, cSym.getType(), 0);
+
+            writer.print("  typedef ");
+            writer.print(funcPtrType.toString(funcPointerTypedefLocalName, localTypedefCallingConvention));
+            writer.println(";");
 
             writer.print("  ");
-            writer.print(funcPointerTypedefName);
+            writer.print(funcPointerTypedefName); // Uses public typedef if available!
             writer.print(" ptr_");
             writer.print(cSym.getName());
             writer.println(";");
@@ -161,17 +159,26 @@ public class ProcAddressCMethodBindingEmitter extends CMethodBindingEmitter {
         if (callThroughProcAddress) {
             // set the function pointer to the value of the passed-in procAddress
             final FunctionSymbol cSym = getBinding().getCSymbol();
-            String funcPointerTypedefName = emitter.getFunctionPointerTypedefName(cSym);
-            if (needsLocalTypedef) {
-                funcPointerTypedefName = "_local_" + funcPointerTypedefName;
+
+            // See above notes in emitBodyVariableDeclarations(..)!
+            final String funcPointerTypedefBaseName = emitter.getFunctionPointerTypedefName(cSym);
+            final String funcPointerTypedefLocalName = "_local_" + funcPointerTypedefBaseName;
+            final String funcPointerTypedefName;
+            if (hasProcAddrTypedef) {
+                funcPointerTypedefName = funcPointerTypedefBaseName;
+            } else {
+                funcPointerTypedefName = funcPointerTypedefLocalName;
             }
 
             final String ptrVarName = "ptr_" + cSym.getName();
 
+            if (hasProcAddrTypedef) {
+                writer.println("  // implicit type validation of "+funcPointerTypedefLocalName+" -> "+funcPointerTypedefName);
+            }
             writer.print("  ");
             writer.print(ptrVarName);
             writer.print(" = (");
-            writer.print(funcPointerTypedefName);
+            writer.print(funcPointerTypedefLocalName);
             writer.println(") (intptr_t) procAddress;");
 
             writer.println("  assert(" + ptrVarName + " != NULL);");