auto-strip profiler prefix set in jna.profiler.prefix

CHANGES.md

@@ -16,6 +16,7 @@ Features
 * Added memory dump for debugging (see `com.sun.jna.Memory`) - [@twall](https://github.com/twall).
 * Improved caching of Structure alignment, type mapping, and encoding information - [@twall](https://github.com/twall).
 * [#225](https://github.com/twall/jna/pull/225): Added `platform.win32.Kernel32.GetLogicalProcessorInformation` and `platform.win32.Kernel32Util.getLogicalProcessorInformation` - [@trejkaz](https://github.com/trejkaz).
+* [#236](https://github.com/twall/jna/issues/236): Auto-strip profiler native method prefix specified by `jna.profiler.prefix`, which defaults to $$YJP$$ - [@twall](https://github.com/twall).
 
 Bug Fixes
 ---------

src/com/sun/jna/Native.java

@@ -1454,12 +1454,7 @@ else if (cvt[t] == CVT_TYPE_MAPPER) {
                 }
             }
 
-            String name = method.getName();
-            FunctionMapper fmapper = (FunctionMapper)lib.getOptions().get(Library.OPTION_FUNCTION_MAPPER);
-            if (fmapper != null) {
-                name = fmapper.getFunctionName(lib, method);
-            }
-            Function f = lib.getFunction(name, method);
+            Function f = lib.getFunction(method.getName(), method);
             try {
                 handles[i] = registerMethod(cls, method.getName(),
                                             sig, cvt,
@@ -1842,6 +1837,8 @@ static String getString(long addr, String encoding) {
         <em>Warning</em>: avoid calling {@link #detach detach(true)} on threads
         spawned by the JVM; the resulting behavior is not defined.
      */
+    // TODO: keep references to Java non-detached threads, and clear them when
+    // native side sets a flag saying they're detached (cleanup)
     public static native void detach(boolean detach);
 
     private static class Buffers {

src/com/sun/jna/NativeLibrary.java

@@ -436,6 +436,11 @@ Function getFunction(String name, Method method) {
         if (mapper != null) {
             name = mapper.getFunctionName(this, method);
         }
+        // If there's native method profiler prefix, strip it
+        String prefix = System.getProperty("jna.profiler.prefix", "$$YJP$$");
+        if (name.startsWith(prefix)) {
+            name = name.substring(prefix.length());
+        }
         int flags = this.callFlags;
         Class[] etypes = method.getExceptionTypes();
         for (int i=0;i < etypes.length;i++) {

test/com/sun/jna/DirectTest.java

@@ -264,6 +264,7 @@ public void testGetOptionsForDirectMappingWithStaticInitializer() {
     }
 
     static class RemappedCLibrary {
+        public static native int $$YJP$$strlen(String s);
         public static native int _prefixed_strlen(String s);
     }
 
@@ -283,7 +284,12 @@ public String getFunctionName(NativeLibrary lib, Method method) {
             Native.register(RemappedCLibrary.class,
                             NativeLibrary.getInstance(Platform.C_LIBRARY_NAME, options));
             final String VALUE = getName();
-            int len = RemappedCLibrary._prefixed_strlen(VALUE);
+            int len;
+
+            len = RemappedCLibrary.$$YJP$$strlen(VALUE);
+            assertEquals(VALUE.length(), len);
+
+            len = RemappedCLibrary._prefixed_strlen(VALUE);
             assertEquals(VALUE.length(), len);
         }
         catch(Exception e) {

www/DirectMapping.md

@@ -24,3 +24,6 @@ Direct mapping supports the same type mappings as interface mapping, except for
 
 You can easily convert from interface mapping to direct mapping by creating a direct mapping class which implements your library interface, with all methods defined as native methods. Then your library instance variable can be assigned an instance of this new class instead of the object returned by `Native.loadLibrary()`.
 
+If you are using a profile which rewrites native methods, you may need to
+set the system property `jna.profiler.prefix` to the prefix used by the
+profiler to avoid linkage errors when binding to native methods.