# CTObjectiveCRuntimeAdditions

**Repository Path**: vww/CTObjectiveCRuntimeAdditions

## Basic Information

- **Project Name**: CTObjectiveCRuntimeAdditions
- **Description**: 快速获取block的参数信息。网上好多资料都是使用 debugserver + lldb 的方法，参考文章， 这种方法的缺点很明显：计算麻烦，需要配置，容易出错。我在逛论坛是无意间发现了一个更快捷的方法就是通过 CTObjectiveCRuntimeAdditions 快速获取block的参数信息。它的原理就是根据LLVM文档，把block重新实现了一遍，然后获取内部参数。
- **Primary Language**: Unknown
- **License**: MIT
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2023-10-20
- **Last Updated**: 2023-10-20

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

CTObjectiveCRuntimeAdditions
============================

CTObjectiveCRuntimeAdditions introduces the following new runtime additions:

* `void class_swizzleSelector(Class class, SEL originalSelector, SEL newSelector);`
* `void class_swizzlesMethodsWithPrefix(Class class, NSString *prefix);`
* `void class_enumerateMethodList(Class class, CTMethodEnumertor enumerator);`
* `Class class_subclassPassingTest(Class class, CTClassTest test);`
* `IMP class_replaceMethodWithBlock(Class class, SEL originalSelector, id block);`
* `void class_implementPropertyInUserDefaults(Class class, NSString *propertyName, BOOL automaticSynchronizeUserDefaults);`
* `void class_implementProperty(Class class, NSString *propertyName, objc_AssociationPolicy associationPolicy);`


Getting runtime information about blocks
============================
[CTBlockDescription](https://github.com/ebf/CTObjectiveCRuntimeAdditions/blob/master/CTObjectiveCRuntimeAdditions/CTObjectiveCRuntimeAdditions/CTBlockDescription.h) lets you inspect blocks including arguments and compile time features at runtime.

One could use CTBlockDescription for the following test block:

``` objc
// a test block.
BOOL(^testBlock)(BOOL animated, id object) = ^BOOL(BOOL animated, id object) {
    return YES;
};

// allocating a block description
CTBlockDescription *blockDescription = [[CTBlockDescription alloc] initWithBlock:testBlock];

// getting a method signature for this block
NSMethodSignature *methodSignature = blockDescription.blockSignature;
/**
<NSMethodSignature: 0x253f080>
    number of arguments = 3
    frame size = 12
    is special struct return? NO
    return value: -------- -------- -------- --------
        type encoding (c) 'c'
        flags {isSigned}
        modifiers {}
        frame {offset = 0, offset adjust = 0, size = 4, size adjust = -3}
        memory {offset = 0, size = 1}
    argument 0: -------- -------- -------- --------
        type encoding (@) '@?'
        flags {isObject, isBlock}
        modifiers {}
        frame {offset = 0, offset adjust = 0, size = 4, size adjust = 0}
        memory {offset = 0, size = 4}
    argument 1: -------- -------- -------- --------
        type encoding (c) 'c'
        flags {isSigned}
        modifiers {}
        frame {offset = 4, offset adjust = 0, size = 4, size adjust = -3}
        memory {offset = 0, size = 1}
    argument 2: -------- -------- -------- --------
        type encoding (@) '@'
        flags {isObject}
        modifiers {}
        frame {offset = 8, offset adjust = 0, size = 4, size adjust = 0}
        memory {offset = 0, size = 4}
*/
```

License
============================
MIT

Thanks goes to the [Block Implementation Specification](http://clang.llvm.org/docs/Block-ABI-Apple.txt) and the [A2DynamicDelegate](https://github.com/pandamonia/A2DynamicDelegate) project for some good libffi samples and convertion from encodings to libffi types.