Re: [RFC 4/7] hostapd: add dfs support into interface init flow

[Felix Fietkau <nbd@openwrt.org>]

On 2012-01-26 1:41 PM, Victor Goldenshtein wrote:
> Implement Channel Availability Check (CAC) during initialization
> phase. According to DFS requirements the AP should monitor 'radar
> channels' for potential radar interference for a minimum CAC time
> prior enabling the transmissions.
> 
> Add dfs support into hw features, allow the usage of the radar
> channels if ieee80211h is enabled in the hostapd.conf and the
> driver supports radar detection.
> 
> Parse and handle driver's DFS capabilities, userspace applications
> must be fully synchronized with device capabilities to detect radar
> patterns in the air which may influence userspace behavior.
> 
> Signed-off-by: Boris Presman <boris.presman@ti.com>
> Signed-off-by: Victor Goldenshtein <victorg@ti.com>
> ---
>  src/ap/hostapd.c             |   17 +++++++++++------
>  src/ap/hw_features.c         |   30 ++++++++++++++++++++----------
>  src/ap/hw_features.h         |    9 +++++++++
>  src/drivers/driver.h         |    5 +++++
>  src/drivers/driver_nl80211.c |    7 +++++++
>  src/utils/eloop.c            |    4 ++++
>  src/utils/eloop.h            |    7 +++++++
>  7 files changed, 63 insertions(+), 16 deletions(-)
> 
> diff --git a/src/ap/hostapd.c b/src/ap/hostapd.c
> index ce37922..411b681 100644
> --- a/src/ap/hostapd.c
> +++ b/src/ap/hostapd.c
> @@ -733,14 +739,13 @@ int hostapd_setup_interface_complete(struct hostapd_iface *iface, int err)
>  			   hostapd_hw_mode_txt(hapd->iconf->hw_mode),
>  			   hapd->iconf->channel, iface->freq);
>  
> -		if (hostapd_set_freq(hapd, hapd->iconf->hw_mode, iface->freq,
> -				     hapd->iconf->channel,
> -				     hapd->iconf->ieee80211n,
> -				     hapd->iconf->secondary_channel)) {
> -			wpa_printf(MSG_ERROR, "Could not set channel for "
> -				   "kernel driver");
> +		if (hostapd_check_set_freq(hapd)) {
> +			wpa_printf(MSG_ERROR, "Couldn't check/set freq");
>  			return -1;
>  		}
> +
> +		eloop_enable();
> +		wpa_printf(MSG_DEBUG, "Continuing with init flow");
>  	}
>  
>  	if (iface->current_mode) {
This seems like a bit of a hack to me. Wouldn't it be better to prevent
eloop_terminate() from being called instead of adding another function
to override the eloop termination?

- Felix