Cache classes with their path & add ScanData for PatchData

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

@@ -7,12 +7,14 @@ import net.revanced.patcher.resolver.MethodResolver
 import net.revanced.patcher.signature.Signature
 import net.revanced.patcher.util.Jar2ASM
 import java.io.InputStream
+import java.io.OutputStream
 import java.util.jar.JarFile
 
 /**
  * The patcher. (docs WIP)
  *
- * @param input the input stream to read from, must be a JAR file (for now)
+ * @param input the input stream to read from, must be a JAR
+ * @param signatures the signatures
  */
 class Patcher (
     input: InputStream,
@@ -22,7 +24,8 @@ class Patcher (
     private val patches: MutableList<Patch> = mutableListOf()
 
     init {
-        cache.methods.putAll(MethodResolver(Jar2ASM.jar2asm(input), signatures).resolve())
+        cache.classes.putAll(Jar2ASM.jar2asm(input))
+        cache.methods.putAll(MethodResolver(cache.classes.values.toList(), signatures).resolve())
     }
 
     fun addPatches(vararg patches: Patch) {
@@ -43,4 +46,8 @@ class Patcher (
             }
         }
     }
+
+    fun save(output: OutputStream) {
+        
+    }
 }

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

@@ -1,8 +1,11 @@
 package net.revanced.patcher.cache
 
-data class Cache(
+import org.objectweb.asm.tree.ClassNode
+
+class Cache {
+    val classes: MutableMap<String, ClassNode> = mutableMapOf()
     val methods: MethodMap = MethodMap()
-)
+}
 
 class MethodMap : LinkedHashMap<String, PatchData>() {
     override fun get(key: String): PatchData {

src/main/kotlin/net/revanced/patcher/cache/PatchData.kt

@@ -5,5 +5,11 @@ import org.objectweb.asm.tree.MethodNode
 
 data class PatchData(
     val cls: ClassNode,
-    val method: MethodNode
+    val method: MethodNode,
+    val sr: ScanData
+)
+
+data class ScanData(
+    val startIndex: Int,
+    val endIndex: Int
 )

src/main/kotlin/net/revanced/patcher/resolver/MethodResolver.kt

@@ -2,6 +2,7 @@ package net.revanced.patcher.resolver
 
 import mu.KotlinLogging
 import net.revanced.patcher.cache.PatchData
+import net.revanced.patcher.cache.ScanData
 import net.revanced.patcher.signature.Signature
 import org.objectweb.asm.Type
 import org.objectweb.asm.tree.ClassNode
@@ -22,12 +23,21 @@ internal class MethodResolver(private val classList: List<ClassNode>, private va
                         continue
                     }
                     logger.debug { "Resolving sig ${signature.name}: ${classNode.name} / ${method.name}" }
-                    if (!this.cmp(method, signature)) {
+                    val (r, sr) = this.cmp(method, signature)
+                    if (!r || sr == null) {
                         logger.debug { "Compare result for sig ${signature.name} has failed!" }
                         continue
                     }
                     logger.debug { "Method for sig ${signature.name} found!" }
-                    patchData[signature.name] = PatchData(classNode, method)
+                    patchData[signature.name] = PatchData(
+                        classNode,
+                        method,
+                        ScanData(
+                            // sadly we cannot create contracts for a data class, so we must assert
+                            sr.startIndex!!,
+                            sr.endIndex!!
+                        )
+                    )
                 }
             }
         }
@@ -40,28 +50,27 @@ internal class MethodResolver(private val classList: List<ClassNode>, private va
         return patchData
     }
 
-    private fun cmp(method: MethodNode, signature: Signature): Boolean {
+    private fun cmp(method: MethodNode, signature: Signature): Pair<Boolean, ScanResult?> {
         if (signature.returns != Type.getReturnType(method.desc)) {
             logger.debug { "Comparing sig ${signature.name}: invalid return type:\nexpected ${signature.returns},\ngot ${Type.getReturnType(method.desc)}" }
-            return false
+            return false to null
         }
         if (signature.accessors != method.access) {
             logger.debug { "Comparing sig ${signature.name}: invalid accessors:\nexpected ${signature.accessors},\ngot ${method.access}" }
-            return false
+            return false to null
         }
         if (!signature.parameters.contentEquals(Type.getArgumentTypes(method.desc))) {
             logger.debug { "Comparing sig ${signature.name}: invalid parameter types:\nexpected ${signature.parameters},\ngot ${Type.getArgumentTypes(method.desc)}" }
-            return false
+            return false to null
         }
 
         val result = method.instructions.scanFor(signature.opcodes)
         if (!result.found) {
             logger.debug { "Comparing sig ${signature.name}: invalid opcode pattern" }
-            return false
+            return false to null
         }
-        // TODO make use of the startIndex and endIndex we have from the result
 
-        return true
+        return true to result
     }
 }
 

src/main/kotlin/net/revanced/patcher/util/ASMWriter.kt

@@ -0,0 +1,5 @@
+package net.revanced.patcher.util
+
+object ASMWriter {
+
+}

src/main/kotlin/net/revanced/patcher/util/Jar2ASM.kt

@@ -6,15 +6,15 @@ import java.io.InputStream
 import java.util.jar.JarInputStream
 
 object Jar2ASM {
-    fun jar2asm(input: InputStream): List<ClassNode> {
-        return buildList {
+    fun jar2asm(input: InputStream): Map<String, ClassNode> {
+        return buildMap {
             val jar = JarInputStream(input)
             while (true) {
                 val e = jar.nextJarEntry ?: break
                 if (e.name.endsWith(".class")) {
                     val classNode = ClassNode()
                     ClassReader(jar.readAllBytes()).accept(classNode, ClassReader.EXPAND_FRAMES)
-                    this.add(classNode)
+                    this[e.name] = classNode
                 }
             }
         }