Re: [PATCH 16/30] bsd-user/signal.c: host_to_target_siginfo_noswap

[Peter Maydell]

On Sun, 9 Jan 2022 at 16:41, Warner Losh <imp@bsdimp.com> wrote:
>
> Implement conversion of host to target siginfo.
>
> Signed-off-by: Stacey Son <sson@FreeBSD.org>
> Signed-off-by: Kyle Evans <kevans@freebsd.org>
> Signed-off-by: Warner Losh <imp@bsdimp.com>
> ---
>  bsd-user/signal.c | 37 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
>
> diff --git a/bsd-user/signal.c b/bsd-user/signal.c
> index 7168d851be8..3fe8b2d9898 100644
> --- a/bsd-user/signal.c
> +++ b/bsd-user/signal.c
> @@ -43,6 +43,43 @@ int target_to_host_signal(int sig)
>      return sig;
>  }
>
> +/* Siginfo conversion. */
> +static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo,
> +        const siginfo_t *info)
> +{
> +    int sig, code;
> +
> +    sig = host_to_target_signal(info->si_signo);
> +    /* XXX should have host_to_target_si_code() */
> +    code = tswap32(info->si_code);
> +    tinfo->si_signo = sig;
> +    tinfo->si_errno = info->si_errno;
> +    tinfo->si_code = info->si_code;
> +    tinfo->si_pid = info->si_pid;
> +    tinfo->si_uid = info->si_uid;
> +    tinfo->si_status = info->si_status;
> +    tinfo->si_addr = (abi_ulong)(unsigned long)info->si_addr;
> +    /* si_value is opaque to kernel */
> +    tinfo->si_value.sival_ptr =
> +        (abi_ulong)(unsigned long)info->si_value.sival_ptr;
> +    if (SIGILL == sig || SIGFPE == sig || SIGSEGV == sig || SIGBUS == sig ||

Don't use yoda-conditions, please. sig == SIGILL, etc.

> +            SIGTRAP == sig) {
> +        tinfo->_reason._fault._trapno = info->_reason._fault._trapno;
> +    }
> +#ifdef SIGPOLL
> +    if (SIGPOLL == sig) {
> +        tinfo->_reason._poll._band = info->_reason._poll._band;
> +    }
> +#endif
> +    if (SI_TIMER == code) {
> +        int timerid;
> +
> +        timerid = info->_reason._timer._timerid;
> +        tinfo->_reason._timer._timerid = timerid;
> +        tinfo->_reason._timer._overrun = info->_reason._timer._overrun;
> +    }
> +}

I think this will only compile on FreeBSD (the other BSDs having
notably different target_siginfo_t structs); I guess we're OK
with that ?

I also commented on the general setup linux-user has for this
function back in patch 2; I'll let you figure out whether what
you have here is the right thing for BSD.

-- PMM