Re: [dpdk-dev] [PATCH v2] app/testpmd: avoid exit without terminal restore

["Li, Xiaoyun" <xiaoyun.li@intel.com>]

Hi

> -----Original Message-----
> From: dapengx.yu@intel.com <dapengx.yu@intel.com>
> Sent: Monday, January 25, 2021 11:30
> To: Xing, Beilei <beilei.xing@intel.com>; Li, Xiaoyun <xiaoyun.li@intel.com>; Lu,
> Wenzhuo <wenzhuo.lu@intel.com>; Iremonger, Bernard
> <bernard.iremonger@intel.com>; stephen@networkplumber.org
> Cc: dev@dpdk.org; Yu, DapengX <dapengx.yu@intel.com>; stable@dpdk.org
> Subject: [PATCH v2] app/testpmd: avoid exit without terminal restore
> 
> From: Dapeng Yu <dapengx.yu@intel.com>
> 
> In interactive mode, if testpmd exit by calling rte_exit without restore terminal
> attributes, terminal will not echo keyboard input.
> 
> register a function with atexit() in prompt(), when exit() in
> rte_exit() is called, the registered function restores terminal attributes.
> 
> Fixes: 5a8fb55c48ab ("app/testpmd: support unidirectional configuration")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Dapeng Yu <dapengx.yu@intel.com>
> ---
>  app/test-pmd/cmdline.c | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c index
> 89034c8b7..f7e18ba3d 100644
> --- a/app/test-pmd/cmdline.c
> +++ b/app/test-pmd/cmdline.c
> @@ -17116,6 +17116,7 @@ cmdline_read_from_file(const char *filename)
> void
>  prompt(void)
>  {
> +	int ret;
>  	/* initialize non-constant commands */
>  	cmd_set_fwd_mode_init();
>  	cmd_set_fwd_retry_mode_init();
> @@ -17123,15 +17124,23 @@ prompt(void)
>  	testpmd_cl = cmdline_stdin_new(main_ctx, "testpmd> ");
>  	if (testpmd_cl == NULL)
>  		return;
> +
> +	ret = atexit(prompt_exit);
> +	if (ret != 0)
> +		printf("Cannot set exit function for cmdline\n");
> +
>  	cmdline_interact(testpmd_cl);
> -	cmdline_stdin_exit(testpmd_cl);
> +	if (ret != 0)

Why do you need to check ret here?
Even if registers prompt_exit failed, when users type "quit" and then break from cmdline_interact(), cmdline_stdin_exit() should be called to restore terminal settings.

> +		cmdline_stdin_exit(testpmd_cl);
>  }
> 
>  void
>  prompt_exit(void)
>  {
> -	if (testpmd_cl != NULL)
> +	if (testpmd_cl != NULL) {
>  		cmdline_quit(testpmd_cl);
> +		cmdline_stdin_exit(testpmd_cl);
> +	}
>  }
> 
>  static void
> --
> 2.27.0