[LTP] [PATCH] syscalls/send02: Improve message

[Alexey Kodanev]

On 16.10.2020 10:45, Yang Xu wrote:
> This case sometimes fails, output as below:
> 
> tst_test.c:1250: TINFO: Timeout per run is 0h 05m 00s
> send02.c:86: TFAIL: recv() error: EAGAIN/EWOULDBLOCK (11)
> send02.c:86: TFAIL: recv() error: EAGAIN/EWOULDBLOCK (11)
> send02.c:86: TFAIL: recv() error: EAGAIN/EWOULDBLOCK (11)
> send02.c:86: TFAIL: recv() error: EAGAIN/EWOULDBLOCK (11)
> 
> From this output, we don't know which subcase fails(tcp,udp,send,sendto).
> So add some message and make this clear.
> 
> Now this case fails as below:
> tst_test.c:1250: TINFO: Timeout per run is 0h 05m 00s
> send02.c:124: TINFO: Testing TCP send
> send02.c:87: TFAIL: recv() error at the 776 times(expsize 17): EAGAIN/EWOULDBLOCK (11)

recv(..., MSG_DONTWAIT) can fail with EAGAIN/EWOULDBLOCK at any time,
so it should be a valid error... why it is a failure in the test?

If we expect some message to receive, we should call recv() again
for EAGAIN/EWOULDBLOCK errors. And with MSG_MORE case, just return
immediately, i.e. something like this:

       while (1) {
                TEST(recv(sock, recvbuf, RECVSIZE, MSG_DONTWAIT));

                if (TST_RET == -1) {
                        if (TST_ERR == EAGAIN || TST_ERR == EWOULDBLOCK) {
                                if (expsize)
                                        continue;
                                else
                                        break;
                        }

                        /* unexpected error */
                        tst_res(TFAIL | TTERRNO, "recv() error, expsize %ld, it %d", expsize, i);
                        return 0;
                }

		if (TST_RET < 0) {
                        tst_res(TFAIL | TTERRNO, "Invalid recv() return value %ld",
                                TST_RET);
                        return 0;
                }

                if (!expsize || TST_RET != expsize) {
                        tst_res(TFAIL, "recv() read %ld bytes, expected %ld", TST_RET,
                                expsize);
                        return 0;
                }

		break;
	}


> send02.c:124: TINFO: Testing UDP send
> send02.c:87: TFAIL: recv() error at the 1 times(expsize 16): EAGAIN/EWOULDBLOCK (11)
> send02.c:124: TINFO: Testing UDP sendto
> send02.c:87: TFAIL: recv() error at the 1 times(expsize 16): EAGAIN/EWOULDBLOCK (11)
> send02.c:124: TINFO: Testing UDP sendmsg
> send02.c:87: TFAIL: recv() error at the 1 times(expsize 16): EAGAIN/EWOULDBLOCK (11)
> 
> Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com>
> ---
>  testcases/kernel/syscalls/send/send02.c | 20 +++++++++++---------
>  1 file changed, 11 insertions(+), 9 deletions(-)
> 
> diff --git a/testcases/kernel/syscalls/send/send02.c b/testcases/kernel/syscalls/send/send02.c
> index 5630230fa..719e86a90 100644
> --- a/testcases/kernel/syscalls/send/send02.c
> +++ b/testcases/kernel/syscalls/send/send02.c
> @@ -71,7 +71,7 @@ static void setup(void)
>  	memset(sendbuf, 0x42, SENDSIZE);
>  }
>  
> -static int check_recv(int sock, long expsize)
> +static int check_recv(int sock, long expsize, int loop)
>  {
>  	char recvbuf[RECVSIZE] = {0};
>  
> @@ -83,19 +83,20 @@ static int check_recv(int sock, long expsize)
>  			return 1;
>  
>  		/* unexpected error */
> -		tst_res(TFAIL | TTERRNO, "recv() error");
> +		tst_res(TFAIL | TTERRNO, "recv() error at the %d times(expsize"
> +			" %ld)", loop, expsize);

It's better to have a single line message, and arguments on another one:
tst_res(TFAIL | TTERRNO, "recv() error at step %d, expsize %ld",
        ...);

>  		return 0;
>  	}
>  
>  	if (TST_RET < 0) {
> -		tst_res(TFAIL | TTERRNO, "Invalid recv() return value %ld",
> -			TST_RET);
> +		tst_res(TFAIL | TTERRNO, "Invalid recv() return value %ld at"
> +			" the %d times(expsize %ld)", TST_RET, loop, expsize);
>  		return 0;
>  	}
>  
>  	if (TST_RET != expsize) {
> -		tst_res(TFAIL, "recv() read %ld bytes, expected %ld", TST_RET,
> -			expsize);
> +		tst_res(TFAIL, "recv() read %ld bytes, expected %ld at the"
> +			" %d times", TST_RET, expsize, loop);
>  		return 0;
>  	}
>  
> @@ -120,6 +121,7 @@ static void run(unsigned int n)
>  	struct test_case *tc = testcase_list + n;
>  	socklen_t len = sizeof(addr);
>  
> +	tst_res(TINFO, "Testing %s", tc->name);
>  	tst_init_sockaddr_inet_bin(&addr, INADDR_LOOPBACK, 0);
>  	listen_sock = SAFE_SOCKET(tc->domain, tc->type, tc->protocol);
>  	dst_sock = listen_sock;
> @@ -139,19 +141,19 @@ static void run(unsigned int n)
>  			dst_sock = SAFE_ACCEPT(listen_sock, NULL, NULL);
>  
>  		tc->send(sock, sendbuf, SENDSIZE, 0);
> -		ret = check_recv(dst_sock, SENDSIZE);
> +		ret = check_recv(dst_sock, SENDSIZE, i + 1);
>  
>  		if (!ret)
>  			break;
>  
>  		tc->send(sock, sendbuf, SENDSIZE, MSG_MORE);
> -		ret = check_recv(dst_sock, 0);
> +		ret = check_recv(dst_sock, 0, i + 1);
>  
>  		if (!ret)
>  			break;
>  
>  		tc->send(sock, sendbuf, 1, 0);
> -		ret = check_recv(dst_sock, SENDSIZE + 1);
> +		ret = check_recv(dst_sock, SENDSIZE + 1, i + 1);
>  
>  		if (!ret)
>  			break;
>