JavaOpenCL64

src/club/doki7/ffm/util/UnixUtil.java

@@ -0,0 +1,51 @@
+package club.doki7.ffm.util;
+
+import club.doki7.ffm.RawFunctionLoader;
+import club.doki7.ffm.library.JavaSystemLibrary;
+import org.jetbrains.annotations.Nullable;
+
+import java.lang.foreign.FunctionDescriptor;
+import java.lang.foreign.MemorySegment;
+import java.lang.foreign.ValueLayout;
+import java.lang.invoke.MethodHandle;
+import java.nio.charset.StandardCharsets;
+import java.util.Objects;
+
+public final class UnixUtil {
+    /// Force the {@link UnixUtil} class to be loaded, in order to avoid some initialization order
+    /// issues.
+    ///
+    /// @implNote The loading of {@link UnixUtil} is done in the static initializer, involving
+    /// retrieving several function handles. Thus, at the point you call the class methods, if the
+    /// `UnixUtil` class has not been loaded yet, the loading process may reset the `dlerror` value,
+    /// which is not what you want. This method is a workaround to force the class to be loaded and
+    /// initialized, so that the function handles are already retrieved, and the `dlerror` value is
+    /// not reset.
+    public static void forceLoad() {}
+
+    public static @Nullable String dlerror() {
+        try {
+            MethodHandle h = Objects.requireNonNull(hDlerror);
+            MemorySegment result = (MemorySegment) h.invokeExact();
+            if (result.equals(MemorySegment.NULL)) {
+                return null;
+            }
+            return result.reinterpret(Long.MAX_VALUE).getString(0, StandardCharsets.UTF_8);
+        } catch (Throwable e) {
+            return "dlerror failed to retrieve error message: " + e.getMessage();
+        }
+    }
+
+    private static final FunctionDescriptor DESCRIPTOR$dlerror =
+            FunctionDescriptor.of(ValueLayout.ADDRESS.withTargetLayout(ValueLayout.JAVA_BYTE));
+    private static final @Nullable MethodHandle hDlerror;
+
+    static {
+        MemorySegment pfnDlerror = JavaSystemLibrary.INSTANCE.load("dlerror");
+        if (pfnDlerror.equals(MemorySegment.NULL)) {
+            hDlerror = null;
+        } else {
+            hDlerror = RawFunctionLoader.link(pfnDlerror, DESCRIPTOR$dlerror);
+        }
+    }
+}