From a43767fa6647953157e5dd26683c46806380e350 Mon Sep 17 00:00:00 2001
From: Nullptr <noreply@nullptr.icu>
Date: Sat, 14 Jan 2023 22:52:36 +0800
Subject: [PATCH] Add HookFailedError

---
 .../libxposed/XposedContextWrapper.java       | 24 +++----
 .../io/github/libxposed/XposedInterface.java  | 63 +++++++++++++++----
 .../libxposed/errors/HookFailedError.java     | 20 ++++++
 .../errors/XposedFrameworkError.java          | 19 ++++++
 4 files changed, 102 insertions(+), 24 deletions(-)
 create mode 100644 api/src/main/java/io/github/libxposed/errors/HookFailedError.java
 create mode 100644 api/src/main/java/io/github/libxposed/errors/XposedFrameworkError.java

diff --git a/api/src/main/java/io/github/libxposed/XposedContextWrapper.java b/api/src/main/java/io/github/libxposed/XposedContextWrapper.java
index 8e5dd5c..d228ad3 100644
--- a/api/src/main/java/io/github/libxposed/XposedContextWrapper.java
+++ b/api/src/main/java/io/github/libxposed/XposedContextWrapper.java
@@ -80,73 +80,73 @@ public class XposedContextWrapper extends ContextWrapper implements XposedInterf
         return getBaseContext().featuredMethod(name, args);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public MethodUnhooker<BeforeHooker<Method>, Method> hookBefore(@NonNull Method origin, @NonNull BeforeHooker<Method> hooker) {
         return getBaseContext().hookBefore(origin, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public MethodUnhooker<AfterHooker<Method>, Method> hookAfter(@NonNull Method origin, @NonNull AfterHooker<Method> hooker) {
         return getBaseContext().hookAfter(origin, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public MethodUnhooker<Hooker<Method>, Method> hook(@NonNull Method origin, @NonNull Hooker<Method> hooker) {
         return getBaseContext().hook(origin, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public MethodUnhooker<BeforeHooker<Method>, Method> hookBefore(@NonNull Method origin, int priority, @NonNull BeforeHooker<Method> hooker) {
         return getBaseContext().hookBefore(origin, priority, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public MethodUnhooker<AfterHooker<Method>, Method> hookAfter(@NonNull Method origin, int priority, @NonNull AfterHooker<Method> hooker) {
         return getBaseContext().hookAfter(origin, priority, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public MethodUnhooker<Hooker<Method>, Method> hook(@NonNull Method origin, int priority, @NonNull Hooker<Method> hooker) {
         return getBaseContext().hook(origin, priority, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public <T> MethodUnhooker<BeforeHooker<Constructor<T>>, Constructor<T>> hookBefore(@NonNull Constructor<T> origin, @NonNull BeforeHooker<Constructor<T>> hooker) {
         return getBaseContext().hookBefore(origin, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public <T> MethodUnhooker<AfterHooker<Constructor<T>>, Constructor<T>> hookAfter(@NonNull Constructor<T> origin, @NonNull AfterHooker<Constructor<T>> hooker) {
         return getBaseContext().hookAfter(origin, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public <T> MethodUnhooker<Hooker<Constructor<T>>, Constructor<T>> hook(@NonNull Constructor<T> origin, @NonNull Hooker<Constructor<T>> hooker) {
         return getBaseContext().hook(origin, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public <T> MethodUnhooker<BeforeHooker<Constructor<T>>, Constructor<T>> hookBefore(@NonNull Constructor<T> origin, int priority, @NonNull BeforeHooker<Constructor<T>> hooker) {
         return getBaseContext().hookBefore(origin, priority, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public <T> MethodUnhooker<AfterHooker<Constructor<T>>, Constructor<T>> hookAfter(@NonNull Constructor<T> origin, int priority, @NonNull AfterHooker<Constructor<T>> hooker) {
         return getBaseContext().hookAfter(origin, priority, hooker);
     }
 
-    @Nullable
+    @NonNull
     @Override
     final public <T> MethodUnhooker<Hooker<Constructor<T>>, Constructor<T>> hook(@NonNull Constructor<T> origin, int priority, @NonNull Hooker<Constructor<T>> hooker) {
         return getBaseContext().hook(origin, priority, hooker);
diff --git a/api/src/main/java/io/github/libxposed/XposedInterface.java b/api/src/main/java/io/github/libxposed/XposedInterface.java
index 6ca2e9c..b8166cc 100644
--- a/api/src/main/java/io/github/libxposed/XposedInterface.java
+++ b/api/src/main/java/io/github/libxposed/XposedInterface.java
@@ -16,6 +16,7 @@ import java.lang.reflect.Method;
 import java.nio.ByteBuffer;
 import java.util.ConcurrentModificationException;
 
+import io.github.libxposed.errors.HookFailedError;
 import io.github.libxposed.utils.DexParser;
 
 /**
@@ -45,6 +46,19 @@ public interface XposedInterface {
      */
     int FRAMEWORK_PRIVILEGE_EMBEDDED = 3;
 
+    /**
+     * The default hook priority.
+     */
+    int PRIORITY_DEFAULT = 50;
+    /**
+     * Execute the hook callback late.
+     */
+    int PRIORITY_LOWEST = -10000;
+    /**
+     * Execute the hook callback early.
+     */
+    int PRIORITY_HIGHEST = 10000;
+
     /**
      * The interface Before hook callback.
      *
@@ -343,6 +357,7 @@ public interface XposedInterface {
      * @param args the args
      * @return the object
      */
+    @Nullable
     Object featuredMethod(String name, Object... args);
 
     /**
@@ -351,8 +366,10 @@ public interface XposedInterface {
      * @param origin the origin
      * @param hooker the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     MethodUnhooker<BeforeHooker<Method>, Method> hookBefore(@NonNull Method origin, @NonNull BeforeHooker<Method> hooker);
 
     /**
@@ -361,8 +378,10 @@ public interface XposedInterface {
      * @param origin the origin
      * @param hooker the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     MethodUnhooker<AfterHooker<Method>, Method> hookAfter(@NonNull Method origin, @NonNull AfterHooker<Method> hooker);
 
     /**
@@ -371,8 +390,10 @@ public interface XposedInterface {
      * @param origin the origin
      * @param hooker the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     MethodUnhooker<Hooker<Method>, Method> hook(@NonNull Method origin, @NonNull Hooker<Method> hooker);
 
     /**
@@ -382,8 +403,10 @@ public interface XposedInterface {
      * @param priority the priority
      * @param hooker   the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     MethodUnhooker<BeforeHooker<Method>, Method> hookBefore(@NonNull Method origin, int priority, @NonNull BeforeHooker<Method> hooker);
 
     /**
@@ -393,8 +416,10 @@ public interface XposedInterface {
      * @param priority the priority
      * @param hooker   the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     MethodUnhooker<AfterHooker<Method>, Method> hookAfter(@NonNull Method origin, int priority, @NonNull AfterHooker<Method> hooker);
 
     /**
@@ -404,8 +429,10 @@ public interface XposedInterface {
      * @param priority the priority
      * @param hooker   the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     MethodUnhooker<Hooker<Method>, Method> hook(@NonNull Method origin, int priority, @NonNull Hooker<Method> hooker);
 
     /**
@@ -415,8 +442,10 @@ public interface XposedInterface {
      * @param origin the origin
      * @param hooker the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     <T> MethodUnhooker<BeforeHooker<Constructor<T>>, Constructor<T>> hookBefore(@NonNull Constructor<T> origin, @NonNull BeforeHooker<Constructor<T>> hooker);
 
     /**
@@ -426,8 +455,10 @@ public interface XposedInterface {
      * @param origin the origin
      * @param hooker the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     <T> MethodUnhooker<AfterHooker<Constructor<T>>, Constructor<T>> hookAfter(@NonNull Constructor<T> origin, @NonNull AfterHooker<Constructor<T>> hooker);
 
     /**
@@ -437,8 +468,10 @@ public interface XposedInterface {
      * @param origin the origin
      * @param hooker the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     <T> MethodUnhooker<Hooker<Constructor<T>>, Constructor<T>> hook(@NonNull Constructor<T> origin, @NonNull Hooker<Constructor<T>> hooker);
 
     /**
@@ -449,8 +482,10 @@ public interface XposedInterface {
      * @param priority the priority
      * @param hooker   the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     <T> MethodUnhooker<BeforeHooker<Constructor<T>>, Constructor<T>> hookBefore(@NonNull Constructor<T> origin, int priority, @NonNull BeforeHooker<Constructor<T>> hooker);
 
     /**
@@ -461,8 +496,10 @@ public interface XposedInterface {
      * @param priority the priority
      * @param hooker   the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     <T> MethodUnhooker<AfterHooker<Constructor<T>>, Constructor<T>> hookAfter(@NonNull Constructor<T> origin, int priority, @NonNull AfterHooker<Constructor<T>> hooker);
 
     /**
@@ -473,8 +510,10 @@ public interface XposedInterface {
      * @param priority the priority
      * @param hooker   the hooker
      * @return the method unhooker
+     * @throws IllegalArgumentException if origin is abstract, framework internal or {@link Method#invoke}
+     * @throws HookFailedError if hook fails due to framework internal error
      */
-    @Nullable
+    @NonNull
     <T> MethodUnhooker<Hooker<Constructor<T>>, Constructor<T>> hook(@NonNull Constructor<T> origin, int priority, @NonNull Hooker<Constructor<T>> hooker);
 
     /**
diff --git a/api/src/main/java/io/github/libxposed/errors/HookFailedError.java b/api/src/main/java/io/github/libxposed/errors/HookFailedError.java
new file mode 100644
index 0000000..1e155c3
--- /dev/null
+++ b/api/src/main/java/io/github/libxposed/errors/HookFailedError.java
@@ -0,0 +1,20 @@
+package io.github.libxposed.errors;
+
+/**
+ * Thrown to indicate that a hook failed due to framework internal error.
+ */
+@SuppressWarnings("unused")
+public class HookFailedError extends XposedFrameworkError {
+
+    public HookFailedError(String message) {
+        super(message);
+    }
+
+    public HookFailedError(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public HookFailedError(Throwable cause) {
+        super(cause);
+    }
+}
diff --git a/api/src/main/java/io/github/libxposed/errors/XposedFrameworkError.java b/api/src/main/java/io/github/libxposed/errors/XposedFrameworkError.java
new file mode 100644
index 0000000..bab03a7
--- /dev/null
+++ b/api/src/main/java/io/github/libxposed/errors/XposedFrameworkError.java
@@ -0,0 +1,19 @@
+package io.github.libxposed.errors;
+
+/**
+ * Thrown to indicate that the Xposed framework function is broken.
+ */
+public abstract class XposedFrameworkError extends Error {
+
+    public XposedFrameworkError(String message) {
+        super(message);
+    }
+
+    public XposedFrameworkError(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public XposedFrameworkError(Throwable cause) {
+        super(cause);
+    }
+}