Re: [Qemu-devel] Coding style, C++ compatible code (was Re: [Qemu-devel] [PATCH 02/22] eepro100: cast a void * makes no sense)

[Gerd Hoffmann]

  Hi,

> Why don't we declare structures like this: typedef struct { ... } T;?
> I suggest this to be the new coding style for structure declarations
> because it is shorter, C++ compatible and unambiguous.

There are quite a few cases where this will simply not work.  They 
usually use a slightly different declaration style though:

typedef struct T T;
struct T {
  /* stuff here */
};

Reasons why this is used/needed:

(1) structs pointing to each other, like this:

typedef struct A A;
typedef struct B B;

struct A {
  B *b;
};
struct B {
  A *a;
};

(2) keep the struct private, let others pass around pointers
    to the struct in a typesafe way though:

header file:

typedef struct T T;
T* get_foo(args);
int do_something_with_foo(T*);

source file:

struct T {
  /* stuff here */
};

cheers,
  Gerd