1 files changed, 50 insertions, 0 deletions
diff --git a/src/main/java/com/code_intelligence/jazzer/utils/ManifestUtils.kt b/src/main/java/com/code_intelligence/jazzer/utils/ManifestUtils.kt
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+++ b/src/main/java/com/code_intelligence/jazzer/utils/ManifestUtils.kt
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+// 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.utils
+
+import java.util.jar.Manifest
+
+object ManifestUtils {
+
+    private const val FUZZ_TARGET_CLASS = "Jazzer-Fuzz-Target-Class"
+    const val HOOK_CLASSES = "Jazzer-Hook-Classes"
+
+    fun combineManifestValues(attribute: String): List<String> {
+        val manifests = ManifestUtils::class.java.classLoader.getResources("META-INF/MANIFEST.MF")
+        return manifests.asSequence().mapNotNull { url ->
+            url.openStream().use { inputStream ->
+                val manifest = Manifest(inputStream)
+                manifest.mainAttributes.getValue(attribute)
+            }
+        }.toList()
+    }
+
+    /**
+     * Returns the value of the `Fuzz-Target-Class` manifest attribute if there is a unique one among all manifest
+     * files in the classpath.
+     */
+    @JvmStatic
+    fun detectFuzzTargetClass(): String? {
+        val fuzzTargets = combineManifestValues(FUZZ_TARGET_CLASS)
+        return when (fuzzTargets.size) {
+            0 -> null
+            1 -> fuzzTargets.first()
+            else -> {
+                Log.warn("More than one Jazzer-Fuzz-Target-Class manifest entry detected on the classpath.")
+                null
+            }
+        }
+    }
+}