为什么MAKEINTRESOURCE（）工作？ [英] Why does MAKEINTRESOURCE() work?

问题描述

宏定义为：

#define MAKEINTRESOURCEA(i) ((LPSTR)((ULONG_PTR)((WORD)(i))))
#define MAKEINTRESOURCEW(i) ((LPWSTR)((ULONG_PTR)((WORD)(i))))

怎么会这可以被用来指示是资源ID（16位无符号整数）或它的名字（一个指向字符数组）？
不这样有效限制的地址空间（32位系统），以16位？否则，系统怎样知道我是否使用ID或名字？

How come this can be used to indicate either a resource ID (a 16-bit unsigned int) or its name (a pointer to an array of char)? Doesn't this effectively limit the address space (on a 32-bit system) to 16-bit? Otherwise how does the system know whether I'm using an ID or a name?

推荐答案

这工作，因为Windows不允许的第一个64 KB的地址空间映射页。为了赶上空指针引用。但我认为还搭上指针漏洞在被从Windows的16位版本的转换程序。

This works because Windows doesn't allow mapping pages for the first 64 KB of the address space. To catch null pointer references. But I think also to catch pointer bugs in programs that were converted from the 16-bit version of Windows.

一个副作用是，这允许可靠地区分包装成一个指针值的资源ID，因为他们永远指向非可映射内存。

A side-effect is that this allows to reliably distinguish resource IDs packed into a pointer value since they'll always point to non-mappable memory.

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