block是包含自变量的匿名函数
0x01.无参数block
int main ()
{
void (^blk)(void) = ^{printf("Block ");}
blk();
return 0;
}
clang -rewrite-objec oc的m文件
struct __block_impl {
void *isa;
int Flags;
int Reserved;
void *FuncPtr;
}
struct __main_block_impl_0 {
struct __block_impl impl;
struct __main_block_desc_0 *Desc;
__main_block_impl_0(void *fp, struct __main_block_desc_0 *desc, int flags = 0) {
impl.isa = &_NSConcreteStackBlock;
impl.Flags = flags;
impl.FuncPtr = fp;
Desc = desc;
}
}
static struct __main_block_func_0 (struct __main_block_impl_0 *__cself) {
printf("Block ");
}
static struct __main_block_desc_0 {
size_t reserved;
size_t Block_size;
} __main_block_desc_0_DATA = { 0, sizeof(struct __main_block_impl_0)};
int main ()
{
void (*blk)(void) = ((void(*)())&__main_block_impl_0((void *)__main_block_func_0, &__main_block_desc_0_DATA));
((void(*)(__block_impl *))((__block_impl *)blk)->FuncPtr)((__block_impl *)blk);
return 0;
}