struct Block_byref_2 *copy2 = (struct Block_byref_2 *)(copy+1); copy2->byref_keep = src2-...>byref_keep; copy2->byref_destroy = src2->byref_destroy; if (src->flags & BLOCK_BYREF_LAYOUT_EXTENDED...3，在源码中，判断BLOCK_BYREF_HAS_COPY_DISPOSE符合之后还会进行byref_keep和byref_destroy的迁移： ?...byref_keep和byref_destroy是定义在Block_byref_2结构体中的： ?...byref_keep对应的就是__Block_byref_id_object_copy_131。
/* VT_BYREF|VT_I8 */ FLOAT * pfltVal; /* VT_BYREF|VT_R4 */.../* VT_BYREF|VT_DATE */ BSTR * pbstrVal; /* VT_BYREF|VT_BSTR */...ppdispVal; /* VT_BYREF|VT_DISPATCH */ SAFEARRAY ** pparray; /* VT_BYREF|...PVOID byref; /* Generic ByRef */ CHAR cVal;.../* VT_BYREF|VT_UI4 */ ULONGLONG * pullVal; /* VT_BYREF|VT_UI8 */
__Block_byref_age_0赋值 __isa指针 ：__Block_byref_age_0中也有isa指针也就是说__Block_byref_age_0本质也一个对象。...__flags ：0 __size ：sizeof(__Block_byref_age_0)即__Block_byref_age_0所占用的内存空间。...那么同样的当block内部捕获__block修饰的对象类型的变量时，__Block_byref_person_0结构体内部也会自动添加__Block_byref_id_object_copy和__Block_byref_id_object_dispose...__Block_byref_age_0结构体，堆中__Block_byref_age_0结构体内的__forwarding指针依然指向自己。..._0结构体声明 __attribute__((__blocks__(byref))) __Block_byref_person_0 person = { (void*)0, (__Block_byref_person
__isa指针 ：__Block_byref_age_0中也有isa指针也就是说__Block_byref_age_0本质也一个对象。...__flags ：0 __size ：sizeof(__Block_byref_age_0),即__Block_byref_age_0所占用的内存空间。...接着将__Block_byref_age_0结构体age存入__main_block_impl_0结构体中，并赋值给__Block_byref_age_0 *age; ?...那么同样的当block内部捕获__block修饰的对象类型的变量时，__Block_byref_person_0结构体内部也会自动添加__Block_byref_id_object_copy和__Block_byref_id_object_dispose...__Block_byref_age_0结构体，堆中__Block_byref_age_0结构体内的__forwarding指针依然指向自己。
Block_layout 3.2 __block修饰后Block_byref模板 struct Block_byref { void *isa; struct Block_byref *...和 byref_destroy 函数 - 来处理里面持有对象的保持和销毁 struct Block_byref_2 { // requires BLOCK_BYREF_HAS_COPY_DISPOSE...内存拷贝 以及常规处理 static struct Block_byref *_Block_byref_copy(const void *arg) { struct Block_byref *..._2 *)(copy+1); copy2->byref_keep = src2->byref_keep; copy2->byref_destroy = src2...Block_byref_3 *src3 = (struct Block_byref_3 *)(src2+1); struct Block_byref_3 *copy3 =
_0 a ={ void* 0, (__Block_byref_a_a *)&a, 0, sizeof(__Block_byref_a_0), 10}; __...main_block_impl_0(func_0,&DATA,&a,570425344); } struct __Block_byref_a_0{ void *isa; __Block_byref_a...*a; __main_block_impl_0(*fp,*desc,__Block_byref_a_0 *_a,flags ):a(a->__forwarding){ impl.isa...修饰的变量 *dest = _Block_byref_copy(object) QQ截图20201215071532.png } } _block_byref_copy..._block_byref_copy(*arg){ struct Block_byref *src = (struct Block_byref *) arg;三层拷贝 struct Block_byref
))) __Block_byref_person_0 person = { (void*)0, (__Block_byref_person_0 *)&person..., 33554432, sizeof(__Block_byref_person_0), __Block_byref_id_object_copy..._0中 struct __Block_byref_person_0 { void *__isa; // isa __Block_byref_person_0 *__forwarding; //指向自己的指针...当block从栈copy到堆中 则指向堆中block的地址 int __flags; // 标记 int __size; // 大小 void (*__Block_byref_id_object_copy...)(void*, void*); // 当block被拷贝到堆中执行此方法 void (*__Block_byref_id_object_dispose)(void*); // 当block释放 执行这个方法
对应于源码中的 __block int val = 1; __attribute__((__blocks__(byref))) __Block_byref_val_0 val = {(void*)0,(...结构体__Block_byref_val_0 __Block_byref_val_0也是一个结构体，该结构体包含如下5个成员变量： void *__isa; __Block_byref_val_0 *_...))) __Block_byref_val_0 val = {(void*)0,(__Block_byref_val_0 *)&val, 0, sizeof(__Block_byref_val_0),...))) __Block_byref_val_0 val = {(void*)0,(__Block_byref_val_0 *)&val, 0, sizeof(__Block_byref_val_0),...__cself->val->__forwarding是结构体__Block_byref_val_0中__Block_byref_val_0类型的成员变量__forwarding，__Block_byref_val
)))__Block_byref_a_0 a = { (void*)0,(__Block_byref_a_0*)&a, 0, sizeof(__Block_byref_a_0)};...)))__Block_byref_a_0 a = {(void*)0,(__Block_byref_a_0 *)&a, 0, sizeof(__Block_byref_a_0)};...; */ int size; void(*byref_keep)(struct Block_byref *dst, structBlock_byref *src); ...)))__Block_byref_a_0 a = {(void*)0,(__Block_byref_a_0 *)&a, 33554432, sizeof(__Block_byref_a_0), __Block_byref_id_object_copy...block this is wrong XXX copy->byref_keep =src->byref_keep; copy->byref_destroy =src->byref_destroy
我们可以先来看看test.cpp的部分实现: struct __Block_byref_b_0 { void *__isa; __Block_byref_b_0 *__forwarding; int...__flags; int __size; int b; }; struct __Block_byref_blockStr_1 { void *__isa; __Block_byref_blockStr...))) __Block_byref_b_0 b = {(void*)0,(__Block_byref_b_0 *)&b, 0, sizeof(__Block_byref_b_0), 20}; NSString...))) __Block_byref_blockStr_1 blockStr = {(void*)0,(__Block_byref_blockStr_1 *)&blockStr, 33554432, sizeof...(__Block_byref_blockStr_1), __Block_byref_id_object_copy_131, __Block_byref_id_object_dispose_131, str
lpSearchCondition As Long, _ ByVal dwSearchCondition As Long, _ ByRef lpGroupId...ByRef lpReserved As Long) As Long Private Declare Function DeleteUrlCacheGroup Lib "wininet.dll...Alias "FindFirstUrlCacheEntryA" ( _ ByVal lpszUrlSearchPattern As String, _ ByRef...lpFirstCacheEntryInfo As INTERNET_CACHE_ENTRY_INFO, _ ByRef lpdwFirstCacheEntryInfoBufferSize...lpNextCacheEntryInfo As INTERNET_CACHE_ENTRY_INFO, _ ByRef lpdwNextCacheEntryInfoBufferSize
… short * piVal; // VT_BYREF|VT_I2. long * plVal; // VT_BYREF|VT_I4. ...float * pfltVal; // VT_BYREF|VT_R4. double * pdblVal; // VT_BYREF|VT_R8. ...DATE * pdate; // VT_BYREF|VT_DATE. ...BSTR * pbstrVal; // VT_BYREF|VT_BSTR. }; }; 显然，VARIANT类型是一个C结构，它包含了一个类型成员vt、一些保留字节以及一个大的union类型
__main_block_impl_0 { struct __block_impl impl; struct __main_block_desc_0* Desc; __Block_byref_val_...))) __Block_byref_val_0 val = {(void*)0,(__Block_byref_val_0 *)&val, 0, sizeof(__Block_byref_val_0), ...其实结构体__Block_byref_val_0产生的实例就是我们使用__block修饰过的变量。...struct __Block_byref_val_0 { void *__isa; __Block_byref_val_0 *__forwarding; int __flags; int __size;...我们从上述被转化的代码中可以看出 Block 本身也一样被转换成了__main_block_impl_0结构体实例，该实例持有__Block_byref_val_0结构体实例的指针。
我们来转换下源码，分析一下： struct __Block_byref_a_0 { void *__isa; __Block_byref_a_0 *__forwarding; int...))) __Block_byref_a_0 a = {(void*)0,(__Block_byref_a_0 *)&a, 0, sizeof(__Block_byref_a_0), 10}; _..._Block_byref_b_1 b = {(void*)0,(__Block_byref_b_1 *)&b, 0, sizeof(__Block_byref_b_1), 20}; void...__Block_byref_a_0、__Block_byref_b_1 类型的结构体声明如下： struct __Block_byref_a_0 { void *__isa; __Block_byref_a...(__Block_byref_a_0), 10 }; __Block_byref_b_1 b = { 0, &b, 0, sizeof(__Block_byref_b
_0 { void *__isa; __Block_byref_age_0 *__forwarding; int __flags; int __size; NSUInteger age; };..._0 *age; // by ref __main_block_impl_0(void *fp, struct __main_block_desc_0 *desc, __Block_byref_age...__main_block_impl_0*src) {_Block_object_assign((void*)&dst->age, (void*)src->age, 8/*BLOCK_FIELD_IS_BYREF.../* @autoreleasepool */ { __AtAutoreleasePool __autoreleasepool; __attribute__((__blocks__(byref...))) __Block_byref_age_0 age = {(void*)0,(__Block_byref_age_0 *)&age, 0, sizeof(__Block_byref_age_0),
编译器会将 __block 修饰的变量包装成一个__Block_byref_age_0对象； 以上age = 20;的赋值过程为：通过 block 结构体里的（__Block_byref_age_0）类型的...age 指针，找到__Block_byref_age_0结构体的内存（即被 __block 包装成对象的内存），把__Block_byref_age_0结构体里的 age 变量的值改为20。...struct __Block_byref_age_0 { void *__isa; __Block_byref_age_0 *__forwarding; int __flags;...))) __Block_byref_age_0 age = {(void*)0,(__Block_byref_age_0 *)&age, 0, sizeof(__Block_byref_age_0),...void (*__Block_byref_id_object_copy)(void*, void*); // copy void (*__Block_byref_id_object_dispose
blobEntropy = DATA_BLOB(len(entropy), bufferEntropy) blobOut = DATA_BLOB() if CryptProtectData(byref...(blobIn), u"python_data", byref(blobEntropy), None, None, CRYPTPROTECT_UI_FORBIDDEN...blobEntropy = DATA_BLOB(len(entropy), bufferEntropy) blobOut = DATA_BLOB() if CryptUnprotectData(byref...(blobIn), None, byref(blobEntropy), None, None, CRYPTPROTECT_UI_FORBIDDEN..., byref(blobOut)): return getData(blobOut) else: return ""7、定义函数来加密和解密数据：def cryptData
char v20[4]; // [sp+10h] [bp-58h] BYREF char v21[4]; // [sp+14h] [bp-54h] BYREF char v22[4]; /...] BYREF char v25[4]; // [sp+24h] [bp-44h] BYREF char v26[4]; // [sp+28h] [bp-40h] BYREF char v27...[4]; // [sp+2Ch] [bp-3Ch] BYREF char v28[4]; // [sp+30h] [bp-38h] BYREF char v29[4]; // [sp+34h]...[bp-34h] BYREF char v30[4]; // [sp+38h] [bp-30h] BYREF char v31[4]; // [sp+3Ch] [bp-2Ch] BYREF...char v32[8]; // [sp+40h] [bp-28h] BYREF int v33; // [sp+48h] [bp-20h] BYREF char v34; // [sp+4Ch]
压缩数据块使用2个byte存储了没有压缩过的数据的长度LEN，再用2个byte记录了LEN的补码NLEN，根据这个，解压代码如下： Private Function InflateNoCompression(ByRef...cpByte() As Byte, ByRef uncpByte() As Byte, ByRef bitIndex As Long, ByRef pUncp As Long) As Long
_0 { void *__isa; __Block_byref_block_i_0 *__forwarding; int __flags; int __size; int block_i; }..._0 *block_i; // by ref __main_block_impl_0(void *fp, struct __main_block_desc_0 *desc, __Block_byref_block_i...main_block_impl_0*src) {_Block_object_assign((void*)&dst->block_i, (void*)src->block_i, 8/*BLOCK_FIELD_IS_BYREF...))) __Block_byref_block_i_0 block_i = {(void*)0,(__Block_byref_block_i_0 *)&block_i, 0, sizeof(__Block_byref_block_i...0; } 可与发现，大概多了三个部分 当block从栈上被copy到堆上时，会调用__main_block_copy_0将__block类型的成员变量i从栈上复制到堆上，同时，栈上的__Block_byref_i
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