[CRIU] [PATCH 2/4] service: page-server: return port back to user

[Pavel Emelyanov]

On 09/18/2014 04:51 AM, Ruslan Kuprieiev wrote:
> Signed-off-by: Ruslan Kuprieiev <kupruser at gmail.com>
> ---
>  cr-service.c | 54 +++++++++++++++++++++++++++++++++++++-----------------
>  1 file changed, 37 insertions(+), 17 deletions(-)
> 
> diff --git a/cr-service.c b/cr-service.c
> index d144f47..e864f16 100644
> --- a/cr-service.c
> +++ b/cr-service.c
> @@ -503,13 +503,19 @@ static int pre_dump_loop(int sk, CriuReq *msg)
>  	return dump_using_req(sk, msg->opts);
>  }
>  
> +struct ps_info {
> +	int pid;
> +	unsigned short port;
> +};
> +
>  static int start_page_server_req(int sk, CriuOpts *req)
>  {
> -	int ret, pid, start_pipe[2];
> +	int ret = -1, pid, start_pipe[2];
>  	ssize_t count;
>  	bool success = false;
>  	CriuResp resp = CRIU_RESP__INIT;
>  	CriuPageServerInfo ps = CRIU_PAGE_SERVER_INFO__INIT;
> +	struct ps_info info;
>  
>  	if (!req->ps) {
>  		pr_err("No page server info in message\n");
> @@ -532,27 +538,41 @@ static int start_page_server_req(int sk, CriuOpts *req)
>  
>  		pr_debug("Starting page server\n");
>  
> -		ret = cr_page_server(true, start_pipe[1]);
> +		pid = cr_page_server(true, start_pipe[1]);
> +		if (pid <= 0)
> +			goto out_ch;
> +
> +		info.pid = pid;
> +		info.port = opts.ps_port;
> +	
> +		count = write(start_pipe[1], &info, sizeof(info));
> +		if (count != sizeof(info))
> +			goto out_ch;
> +
> +		ret = 0;
>  out_ch:
> -		count = write(start_pipe[1], &ret, sizeof(ret));
> +		if (ret < 0 && pid > 0)
> +			kill(pid, SIGKILL);
>  		close(start_pipe[1]);
> -		if (count != sizeof(ret))
> -			exit(1);
> -		exit(0);
> +		exit(ret);
>  	}
>  
>  	close(start_pipe[1]);
> -	wait(NULL);
> -	ret = -1;
> -	count = read(start_pipe[0], &ret, sizeof(ret));
> -	if (count != sizeof(ret))
> -		success = false;
> -	else if (ret > 0) {
> -		success = true;
> -		ps.has_pid = true;
> -		ps.pid = ret;
> -		resp.ps = &ps;
> -	}
> +	wait(&ret);
> +	if (ret)

The status can't (well, shouldn't) be checked like this. The WIFEXITED/WIFSIGNALLED
macros are to be used.

> +		goto out;
> +
> +	count = read(start_pipe[0], &info, sizeof(info));
> +	close(start_pipe[0]);
> +	if (count != sizeof(info))
> +		goto out;
> +
> +	success = true;
> +	ps.has_pid = true;
> +	ps.pid = info.pid;
> +	ps.has_port = true;
> +	ps.port = info.port;
> +	resp.ps = &ps;
>  
>  	pr_debug("Page server started\n");
>  out:
>