support reset arguments

Author: jiang.feng

Example/Stinger/ASViewController.m

@@ -26,6 +26,11 @@ - (void)setFrame:(CGRect)rect {
 
 }
 
+- (BOOL)setFrame:(CGRect)rect object:(NSString *)obj num:(NSInteger)num {
+    NSLog(@"origin fun: %@, %@, %ld", @(rect), obj, num);
+    return YES;
+}
+
 - (void)viewDidLoad {
   [super viewDidLoad];
   [self.class st_hookInstanceMethod:@selector(methodA) option:STOptionBefore usingIdentifier:@"hook methodA before" withBlock:^(id<StingerParams> params) {
@@ -34,7 +39,18 @@ - (void)viewDidLoad {
   [self.class st_hookInstanceMethod:@selector(methodA) option:STOptionAfter usingIdentifier:@"hook methodA after" withBlock:^(id<StingerParams> params) {
 
   }];
-  
+    
+    [self.class st_hookInstanceMethod:@selector(setFrame:object:num:) option:STOptionAfter usingIdentifier:@"change arg" withBlock:^BOOL(id<StingerParams> params, CGRect rect, NSString *obj, NSInteger num) {
+        [params setArgument:@(CGRectMake(5, 6, 7, 8)) atIndex:0];
+        [params setArgument:@"hook success" atIndex:1];
+        [params setArgument:@(num + 1) atIndex:2];
+        BOOL returnValue;
+        [params invokeAndGetOriginalRetValue:&returnValue];
+        return returnValue;
+    }];
+    [self setFrame:CGRectMake(1, 2, 3, 4) object:@"not hook" num:111];
+    
+    
 //  [self.class aspect_hookSelector:@selector(methodA) withOptions:AspectPositionBefore usingBlock:^(id<AspectInfo> params) {
 //
 //  } error:nil];

Stinger/Classes/STDefines.h

@@ -53,6 +53,7 @@ typedef NS_ENUM(NSInteger, STHookResult) {
 - (SEL)sel;
 - (NSArray *)arguments;
 - (NSString *)typeEncoding;
+- (void)setArgument:(id)arg atIndex:(NSInteger)idx;
 - (void)invokeAndGetOriginalRetValue:(void *)retLoc;
 @end
 

Stinger/Classes/StingerParams.m

@@ -19,7 +19,7 @@ @interface StingerParams ()
 @property (nonatomic) IMP originalIMP;
 @property (nonatomic) void **args;
 @property (nonatomic) NSArray *argumentTypes;
-@property (nonatomic) NSArray *arguments;
+@property (nonatomic) NSMutableArray *arguments;
 @end
 
 @implementation StingerParams
@@ -46,13 +46,37 @@ - (SEL)sel {
 }
 
 - (NSArray *)arguments {
-    return _arguments;
+    return [_arguments copy];
 }
 
 - (NSString *)typeEncoding {
     return _types;
 }
 
+/// 修改函数参数
+/// - Parameters:
+///   - arg: 对应的参数，值类型请转换为NSValue传递
+///   - idx: 序号，默认从0开始
+- (void)setArgument:(id)arg atIndex:(NSInteger)idx {
+    _arguments[idx]= arg;
+    NSString *argTypeStr = _argumentTypes[idx + 2];
+    const char *argType = argTypeStr.UTF8String;
+    if (strcmp(argType, @encode(id)) == 0 || strcmp(argType, @encode(Class)) == 0) {
+        void **objPointer = _args[idx + 2];
+        *objPointer = (__bridge void *)(arg);
+        return;
+    }
+    if ([arg isKindOfClass:NSValue.class]) {
+        if (@available(iOS 11.0, *)) {
+            NSUInteger valueSize = 0;
+            NSGetSizeAndAlignment(argType, &valueSize, NULL);
+            [(NSValue *)arg getValue:_args[idx + 2] size:valueSize];
+        } else {
+            [(NSValue *)arg getValue:_args[idx + 2]];
+        }
+    }
+}
+
 - (void)invokeAndGetOriginalRetValue:(void *)retLoc {
   NSMethodSignature *signature = [NSMethodSignature signatureWithObjCTypes:_types.UTF8String];
   NSInteger count = signature.numberOfArguments;
@@ -69,12 +93,11 @@ - (void)invokeAndGetOriginalRetValue:(void *)retLoc {
 #pragma - mark Private
 
 - (void)st_genarateArguments {
-    NSMutableArray *args = [[NSMutableArray alloc] initWithCapacity:_argumentTypes.count];
+    _arguments = [NSMutableArray array];
     for (NSUInteger i = 2; i < _argumentTypes.count; i++) {
         id argument = [self st_argumentWithType:_argumentTypes[i] index:i];
-        [args addObject:argument ?: NSNull.null];
+        [_arguments addObject:argument ?: NSNull.null];
     }
-    _arguments = [args copy];
 }
 
 - (id)st_argumentWithType:(NSString *)type index:(NSUInteger)index {