Re: [Qemu-devel] [PATCH v2 1/3] qemu-io: Add sigraise command

[Fam Zheng <famz@redhat.com>]

On Thu, 12/04 15:49, Max Reitz wrote:
> abort() has the sometimes undesirable side-effect of generating a core
> dump. If that is not needed, SIGKILL has the same effect of abruptly
> crash qemu; without a core dump.
> 
> Thus, -c abort is not always useful to simulate a qemu-io crash;
> therefore, this patch adds a new sigraise command which allows to raise
> any Unix signal.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>  qemu-io-cmds.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 46 insertions(+)
> 
> diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
> index d94fb1e..942b694 100644
> --- a/qemu-io-cmds.c
> +++ b/qemu-io-cmds.c
> @@ -2048,6 +2048,51 @@ static const cmdinfo_t abort_cmd = {
>         .oneline        = "simulate a program crash using abort(3)",
>  };
>  
> +static void sigraise_help(void)
> +{
> +    printf(
> +"\n"
> +" raises the given Unix signal\n"
> +"\n"
> +" Example:\n"
> +" 'sigraise 9' - raises SIGKILL\n"
> +"\n"
> +" Invokes raise(signal), where \"signal\" is the mandatory integer argument\n"
> +" given to sigraise.\n"
> +"\n");
> +}
> +
> +static int sigraise_f(BlockDriverState *bs, int argc, char **argv);
> +
> +static const cmdinfo_t sigraise_cmd = {
> +    .name       = "sigraise",
> +    .cfunc      = sigraise_f,
> +    .argmin     = 1,
> +    .argmax     = 1,
> +    .flags      = CMD_NOFILE_OK,
> +    .args       = "signal",
> +    .oneline    = "raises a Unix signal",
> +    .help       = sigraise_help,
> +};
> +
> +static int sigraise_f(BlockDriverState *bs, int argc, char **argv)
> +{
> +    int sig = cvtnum(argv[1]);
> +    if (sig < 0) {
> +        printf("non-numeric signal number argument -- %s\n", argv[1]);
> +        return 0;
> +    }
> +
> +    /* Using raise() to kill this process does not necessarily flush all open
> +     * streams. At least stdout and stderr (although the latter should be
> +     * non-buffered anyway) should be flushed, though. */
> +    fflush(stdout);
> +    fflush(stderr);
> +
> +    raise(sig);
> +    return 0;
> +}
> +
>  static void sleep_cb(void *opaque)
>  {
>      bool *expired = opaque;
> @@ -2202,4 +2247,5 @@ static void __attribute((constructor)) init_qemuio_commands(void)
>      qemuio_add_command(&wait_break_cmd);
>      qemuio_add_command(&abort_cmd);
>      qemuio_add_command(&sleep_cmd);
> +    qemuio_add_command(&sigraise_cmd);
>  }
> -- 
> 1.9.3
> 
> 

Reviewed-by: Fam Zheng <famz@redhat.com>