Add CTRL-EVENT-CHANNEL-SWITCH event to indicate channel changes

This provides information of the channel switch to wpa_supplicant
control interface monitors.

Signed-off-by: Jouni Malinen <j@w1.fi>

src/common/wpa_ctrl.h

@@ -76,6 +76,8 @@ extern "C" {
 #define WPA_EVENT_SIGNAL_CHANGE "CTRL-EVENT-SIGNAL-CHANGE "
 /** Regulatory domain channel */
 #define WPA_EVENT_REGDOM_CHANGE "CTRL-EVENT-REGDOM-CHANGE "
+/** Channel switch (followed by freq=<MHz> and other channel parameters) */
+#define WPA_EVENT_CHANNEL_SWITCH "CTRL-EVENT-CHANNEL-SWITCH "
 
 /** IP subnet status change notification
  *

wpa_supplicant/events.c

@@ -3669,6 +3669,15 @@ void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
 		if (!data || !wpa_s->current_ssid)
 			break;
 
+		wpa_msg(wpa_s, MSG_INFO, WPA_EVENT_CHANNEL_SWITCH
+			"freq=%d ht_enabled=%d ch_offset=%d ch_width=%s cf1=%d cf2=%d",
+			data->ch_switch.freq,
+			data->ch_switch.ht_enabled,
+			data->ch_switch.ch_offset,
+			channel_width_to_string(data->ch_switch.ch_width),
+			data->ch_switch.cf1,
+			data->ch_switch.cf2);
+
 		wpa_s->assoc_freq = data->ch_switch.freq;
 		wpa_s->current_ssid->frequency = data->ch_switch.freq;