Add initial AccessWidener

2026-06-11 12:22:44 +02:00
parent e176b3bca8
commit 786257ad0e
15 changed files with 979 additions and 6 deletions
@@ -0,0 +1,98 @@
+/*
+ *   This file is a part of the SteamWar software.
+ *
+ *   Copyright (C) 2026 SteamWar.de-Serverteam
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU Affero General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU Affero General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Affero General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar;
+
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.FieldVisitor;
+import org.objectweb.asm.MethodVisitor;
+import org.objectweb.asm.Opcodes;
+
+import java.util.List;
+
+public class ClassTransformer extends ClassVisitor {
+
+    private final String internalName;
+    private final List<AccessWidenerEntry> entries;
+
+    public ClassTransformer(ClassVisitor cv, String internalName, List<AccessWidenerEntry> entries) {
+        super(Opcodes.ASM9, cv);
+        this.internalName = internalName;
+        this.entries = entries;
+    }
+
+    @Override
+    public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
+        int newAccess = access;
+        for (AccessWidenerEntry e : entries) {
+            if (!e.targets(internalName) || !"class".equals(e.memberType())) continue;
+            newAccess = applyDirective(e.directive(), newAccess, false);
+        }
+        super.visit(version, newAccess, name, signature, superName, interfaces);
+    }
+
+    @Override
+    public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
+        int newAccess = access;
+        for (AccessWidenerEntry e : entries) {
+            if (!e.targets(internalName) || !"method".equals(e.memberType())) continue;
+            if (!name.equals(e.name()) || !descriptor.equals(e.descriptor())) continue;
+            newAccess = applyDirective(e.directive(), newAccess, false);
+        }
+        return super.visitMethod(newAccess, name, descriptor, signature, exceptions);
+    }
+
+    @Override
+    public FieldVisitor visitField(int access, String name, String descriptor, String signature, Object value) {
+        int newAccess = access;
+        for (AccessWidenerEntry e : entries) {
+            if (!e.targets(internalName) || !"field".equals(e.memberType())) continue;
+            if (!name.equals(e.name())) continue;
+            newAccess = applyDirective(e.directive(), newAccess, true);
+        }
+        return super.visitField(newAccess, name, descriptor, signature, value);
+    }
+
+    /**
+     * Apply a directive to an access bitmask.
+     *
+     * @param directive accessible / mutable / extendable (with optional "transitive-" prefix)
+     * @param access    current access flags
+     * @param isField   true when processing a field (mutable removes final)
+     */
+    private static int applyDirective(String directive, int access, boolean isField) {
+        // Strip transitive- prefix — the widening itself is the same
+        String effective = directive.startsWith("transitive-") ? directive.substring("transitive-".length()) : directive;
+
+        return switch (effective) {
+            case "accessible" -> makePublic(access);
+            case "extendable" -> makePublic(removeFinal(access));
+            case "mutable" -> isField ? removeFinal(access) : access;
+            default -> access;
+        };
+    }
+
+    private static int makePublic(int access) {
+        return (access & ~(Opcodes.ACC_PRIVATE | Opcodes.ACC_PROTECTED)) | Opcodes.ACC_PUBLIC;
+    }
+
+    private static int removeFinal(int access) {
+        return access & ~Opcodes.ACC_FINAL;
+    }
+}