Bruce Allan wrote:
>
> How about this instead (a combination of your comment above and glibc's
> definition of sockaddr_storage):
> #define _SS_MAXSIZE 128
> #define _ALIGNSIZE (sizeof(struct sockaddr *))
> #if ULONG_MAX > 0xffffffff
> #define __ss_aligntype __u64
> #else
> #define __ss_aligntype __u32
> #endif
> struct sockaddr_storage {
> sa_family_t ss_family;
> __ss_aligntype __data[(_SS_MAXSIZE/sizeof(__ss_aligntype))-1];
> } __attribute__ ((aligned(_ALIGNSIZE)));
>
Hmmm... this seemed to generate a 124-byte struct instead of the stated
intent of 128.
Maybe instead:
#define _SS_MAXSIZE 128
#if ULONG_MAX > 0xffffffff
#define __ss_aligntype __u64
#else
#define __ss_aligntype __u32
#endif
#define _ALIGNSIZE (sizeof(__ss_aligntype))
struct sockaddr_storage {
sa_family_t ss_family;
__ss_aligntype __data[_SS_MAXSIZE/_ALIGNSIZE-1] __attribute__
((aligned(_ALIGNSIZE)));
} __attribute ((aligned(_ALIGNSIZE)));
Align the struct on _ALIGNSIZE; align _data on _ALIGNSIZE to to generate
padding between ss_family and __data.
Best Regards,
jon
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