[lttng-dev] [PATCH lttng-tools] Fix: improve error message when UST support is disabled

[Mathieu Desnoyers]

* Mathieu Desnoyers (mathieu.desnoyers at efficios.com) wrote:
> Fixes #583

Hi David,

I see this patch is merged, but did not received any reply to the email.
Please reply with a "Merged" message to help tracking status of patches
(as you usually do).

Thanks!

Mathieu

> 
> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> ---
> diff --git a/include/lttng/lttng-error.h b/include/lttng/lttng-error.h
> index 51ef9ca..5e0dd07 100644
> --- a/include/lttng/lttng-error.h
> +++ b/include/lttng/lttng-error.h
> @@ -114,7 +114,7 @@ enum lttng_error_code {
>  	LTTNG_ERR_TRACE_ALREADY_STOPPED  = 81,  /* Tracing already stopped */
>  	LTTNG_ERR_KERN_EVENT_ENOSYS      = 82,  /* Kernel event type not supported */
>  	LTTNG_ERR_NEED_CHANNEL_NAME      = 83,	/* Non-default channel exists within session: channel name needs to be specified with '-c name' */
> -	/* 84 */
> +	LTTNG_ERR_NO_UST                 = 84,  /* LTTng-UST tracer is not supported. Please rebuild lttng-tools with lttng-ust support enabled. */
>  	/* 85 */
>  	/* 86 */
>  	/* 87 */
> diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
> index 69bc3a1..4ebd1e7 100644
> --- a/src/bin/lttng-sessiond/main.c
> +++ b/src/bin/lttng-sessiond/main.c
> @@ -2710,6 +2710,10 @@ static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
>  		break;
>  	case LTTNG_DOMAIN_UST:
>  	{
> +		if (!ust_app_supported()) {
> +			ret = LTTNG_ERR_NO_UST;
> +			goto error;
> +		}
>  		/* Consumer is in an ERROR state. Report back to client */
>  		if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
>  			ret = LTTNG_ERR_NO_USTCONSUMERD;
> diff --git a/src/bin/lttng-sessiond/ust-app.h b/src/bin/lttng-sessiond/ust-app.h
> index a08cfd2..fd5e93f 100644
> --- a/src/bin/lttng-sessiond/ust-app.h
> +++ b/src/bin/lttng-sessiond/ust-app.h
> @@ -320,6 +320,12 @@ int ust_app_snapshot_record(struct ltt_ust_session *usess,
>  		struct snapshot_output *output, int wait, unsigned int nb_streams);
>  unsigned int ust_app_get_nb_stream(struct ltt_ust_session *usess);
>  
> +static inline
> +int ust_app_supported(void)
> +{
> +	return 1;
> +}
> +
>  #else /* HAVE_LIBLTTNG_UST_CTL */
>  
>  static inline
> @@ -528,6 +534,12 @@ unsigned int ust_app_get_nb_stream(struct ltt_ust_session *usess)
>  	return 0;
>  }
>  
> +static inline
> +int ust_app_supported(void)
> +{
> +	return 0;
> +}
> +
>  #endif /* HAVE_LIBLTTNG_UST_CTL */
>  
>  #endif /* _LTT_UST_APP_H */
> diff --git a/src/common/error.c b/src/common/error.c
> index 7faba5a..911baea 100644
> --- a/src/common/error.c
> +++ b/src/common/error.c
> @@ -83,6 +83,7 @@ static const char *error_string_array[] = {
>  	[ ERROR_INDEX(LTTNG_ERR_UST_CONTEXT_EXIST)] = "UST context already exist",
>  	[ ERROR_INDEX(LTTNG_ERR_UST_CONTEXT_INVAL)] = "UST invalid context",
>  	[ ERROR_INDEX(LTTNG_ERR_NEED_ROOT_SESSIOND) ] = "Tracing the kernel requires a root lttng-sessiond daemon, as well as \"tracing\" group membership or root user ID for the lttng client.",
> +	[ ERROR_INDEX(LTTNG_ERR_NO_UST) ] = "LTTng-UST tracer is not supported. Please rebuild lttng-tools with lttng-ust support enabled.",
>  	[ ERROR_INDEX(LTTNG_ERR_TRACE_ALREADY_STARTED) ] = "Tracing already started",
>  	[ ERROR_INDEX(LTTNG_ERR_TRACE_ALREADY_STOPPED) ] = "Tracing already stopped",
>  	[ ERROR_INDEX(LTTNG_ERR_KERN_EVENT_ENOSYS) ] = "Kernel event type not supported",
> 
> -- 
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
> 
> _______________________________________________
> lttng-dev mailing list
> lttng-dev at lists.lttng.org
> http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com