1 files changed, 63 insertions, 0 deletions
diff --git a/src/main/java/com/code_intelligence/jazzer/instrumentor/HookInstrumentor.kt b/src/main/java/com/code_intelligence/jazzer/instrumentor/HookInstrumentor.kt
new file mode 100644
index 00000000..3c0d97c9
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+++ b/src/main/java/com/code_intelligence/jazzer/instrumentor/HookInstrumentor.kt
@@ -0,0 +1,63 @@
+// Copyright 2021 Code Intelligence GmbH
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.code_intelligence.jazzer.instrumentor
+
+import org.objectweb.asm.ClassReader
+import org.objectweb.asm.ClassVisitor
+import org.objectweb.asm.ClassWriter
+import org.objectweb.asm.MethodVisitor
+
+internal class HookInstrumentor(
+    private val hooks: Iterable<Hook>,
+    private val java6Mode: Boolean,
+    private val classWithHooksEnabledField: String?,
+) : Instrumentor {
+
+    private lateinit var random: DeterministicRandom
+
+    override fun instrument(internalClassName: String, bytecode: ByteArray): ByteArray {
+        val reader = ClassReader(bytecode)
+        val writer = ClassWriter(reader, ClassWriter.COMPUTE_MAXS)
+        random = DeterministicRandom("hook", reader.className)
+        val interceptor = object : ClassVisitor(Instrumentor.ASM_API_VERSION, writer) {
+            override fun visitMethod(
+                access: Int,
+                name: String?,
+                descriptor: String?,
+                signature: String?,
+                exceptions: Array<String>?,
+            ): MethodVisitor? {
+                val mv = cv.visitMethod(access, name, descriptor, signature, exceptions) ?: return null
+                return if (shouldInstrument(access)) {
+                    makeHookMethodVisitor(
+                        internalClassName,
+                        access,
+                        name,
+                        descriptor,
+                        mv,
+                        hooks,
+                        java6Mode,
+                        random,
+                        classWithHooksEnabledField,
+                    )
+                } else {
+                    mv
+                }
+            }
+        }
+        reader.accept(interceptor, ClassReader.EXPAND_FRAMES)
+        return writer.toByteArray()
+    }
+}