Objective-C底层数据结构

struct _category_t {
    const char *name; //类名
    struct _class_t *cls;
    const struct _method_list_t *instance_methods; //对象方法列表
    const struct _method_list_t *class_methods; //实例方法列表
    const struct _protocol_list_t *protocols;  //协议列表
    const struct _prop_list_t *properties;  //属性列表
};

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struct objc_class : objc_object {
    // Class ISA;
    Class superclass;
    cache_t cache;             // 方法缓存
    class_data_bits_t bits;    // 用于获取类的具体信息

    class_rw_t *data() { 
        return bits.data();
    }
};

struct class_rw_t {
    // Be warned that Symbolication knows the layout of this structure.
    uint32_t flags;
    uint32_t version;

    const class_ro_t *ro;

    method_array_t methods;    //方法列表
    property_array_t properties; //属性列表
    protocol_array_t protocols;   //协议列表

    Class firstSubclass;
    Class nextSiblingClass;

    char *demangledName;
};

struct class_ro_t {
    uint32_t flags;
    uint32_t instanceStart;
    uint32_t instanceSize;
#ifdef __LP64__
    uint32_t reserved;
#endif

    const uint8_t * ivarLayout;
    
    const char * name;   //类名
    method_list_t * baseMethodList;
    protocol_list_t * baseProtocols;
    const ivar_list_t * ivars;    //成员变量列表

    const uint8_t * weakIvarLayout;
    property_list_t *baseProperties;

    method_list_t *baseMethods() const {
        return baseMethodList;
    }
};

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