feat: allow classes to be overwritten in addFiles and resolve signatures when applyPatches is called

build.gradle.kts

@@ -25,7 +25,6 @@ dependencies {
     implementation(kotlin("stdlib"))
 
     api("app.revanced:multidexlib2:2.5.2.r2")
-    @Suppress("GradlePackageUpdate")
     api("org.smali:smali:2.5.2")
 
     testImplementation(kotlin("test"))

src/main/kotlin/app/revanced/patcher/Patcher.kt

@@ -1,6 +1,7 @@
 package app.revanced.patcher
 
 import app.revanced.patcher.cache.Cache
+import app.revanced.patcher.cache.findIndexed
 import app.revanced.patcher.patch.Patch
 import app.revanced.patcher.patch.PatchResultSuccess
 import app.revanced.patcher.signature.resolver.SignatureResolver
@@ -24,31 +25,41 @@ val NAMER = BasicDexFileNamer()
  */
 class Patcher(
     input: File,
-    signatures: Iterable<MethodSignature>,
+    private val signatures: Iterable<MethodSignature>,
 ) {
     private val cache: Cache
     private val patches = mutableSetOf<Patch>()
     private val opcodes: Opcodes
+    private var sigsResolved = false
 
     init {
         val dexFile = MultiDexIO.readDexFile(true, input, NAMER, null, null)
         opcodes = dexFile.opcodes
-        cache = Cache(dexFile.classes.toMutableList(), SignatureResolver(dexFile.classes, signatures).resolve())
+        cache = Cache(dexFile.classes.toMutableList())
     }
     /**
      * Add additional dex file container to the patcher.
      * @param files The dex file containers to add to the patcher.
+     * @param allowedOverwrites A list of class types that are allowed to be overwritten.
      * @param throwOnDuplicates If this is set to true, the patcher will throw an exception if a duplicate class has been found.
      */
-    fun addFiles(vararg files: File, throwOnDuplicates: Boolean = false) {
+    fun addFiles(
+        files: Iterable<File>,
+        allowedOverwrites: Iterable<String> = emptyList(),
+        throwOnDuplicates: Boolean = false
+    ) {
         for (file in files) {
-            val dexFile = MultiDexIO.readDexFile(true, files[0], NAMER, null, null)
+            val dexFile = MultiDexIO.readDexFile(true, file, NAMER, null, null)
             for (classDef in dexFile.classes) {
-                if (cache.classes.any { it.type == classDef.type }) {
-                    // TODO: Use logger and warn about duplicate classes
-                    if (throwOnDuplicates)
+                val e = cache.classes.findIndexed { it.type == classDef.type }
+                if (e != null) {
+                    if (throwOnDuplicates) {
                         throw Exception("Class ${classDef.type} has already been added to the patcher.")
-
+                    }
+                    val (_, idx) = e
+                    if (allowedOverwrites.contains(classDef.type)) {
+                        cache.classes[idx] = classDef
+                    }
                     continue
                 }
                 cache.classes.add(classDef)
@@ -61,7 +72,6 @@ class Patcher(
     fun save(): Map<String, MemoryDataStore> {
         val newDexFile = object : DexFile {
             override fun getClasses(): Set<ClassDef> {
-                // this is a slow workaround for now
                 cache.methodMap.values.forEach {
                     if (it.definingClassProxy.proxyUsed) {
                         cache.classes[it.definingClassProxy.originalIndex] = it.definingClassProxy.mutatedClass
@@ -104,6 +114,10 @@ class Patcher(
      * If the patch failed to apply, an Exception will always be returned in the wrapping Result object.
      */
     fun applyPatches(stopOnError: Boolean = false, callback: (String) -> Unit = {}): Map<String, Result<PatchResultSuccess>> {
+        if (!sigsResolved) {
+            SignatureResolver(cache.classes, signatures).resolve(cache.methodMap)
+            sigsResolved = true
+        }
         return buildMap {
             for (patch in patches) {
                 callback(patch.patchName)

src/main/kotlin/app/revanced/patcher/cache/Cache.kt

@@ -6,7 +6,7 @@ import org.jf.dexlib2.iface.ClassDef
 
 class Cache(
     internal val classes: MutableList<ClassDef>,
-    val methodMap: MethodMap
+    val methodMap: MethodMap = MethodMap()
 ) {
     // TODO: currently we create ClassProxies at multiple places, which is why we could have merge conflicts
     //  this can be solved by creating a dedicated method for creating class proxies,

src/main/kotlin/app/revanced/patcher/signature/resolver/SignatureResolver.kt

@@ -10,14 +10,11 @@ import org.jf.dexlib2.iface.ClassDef
 import org.jf.dexlib2.iface.Method
 import org.jf.dexlib2.iface.instruction.Instruction
 
-// TODO: add logger back
 internal class SignatureResolver(
-    private val classes: Set<ClassDef>,
+    private val classes: List<ClassDef>,
     private val methodSignatures: Iterable<MethodSignature>
 ) {
-    fun resolve(): MethodMap {
-        val methodMap = MethodMap()
-
+    fun resolve(methodMap: MethodMap) {
         for ((index, classDef) in classes.withIndex()) {
             for (signature in methodSignatures) {
                 if (methodMap.containsKey(signature.name)) {
@@ -37,8 +34,6 @@ internal class SignatureResolver(
                 }
             }
         }
-
-        return methodMap
     }
 
     // These functions do not require the constructor values, so they can be static.