DFS: Add new hostapd_is_dfs_overlap() helper

[thirdparty/hostap.git] / src / ap / dfs.c

diff --git a/src/ap/dfs.c b/src/ap/dfs.c
index 2e350ff086b6b2705d0e6f0878e1e48f5e848c31..3c078b9cbf020e1a509d719a41cf8a0615c26dbb 100644 (file)
--- a/src/ap/dfs.c
+++ b/src/ap/dfs.c
@@ -1290,3 +1290,56 @@ int hostapd_handle_dfs_offload(struct hostapd_iface *iface)
                   __func__, iface->freq);
        return 2;
 }
+
+
+int hostapd_is_dfs_overlap(struct hostapd_iface *iface, enum chan_width width,
+                          int center_freq)
+{
+       struct hostapd_channel_data *chan;
+       struct hostapd_hw_modes *mode = iface->current_mode;
+       int half_width;
+       int res = 0;
+       int i;
+
+       if (!iface->conf->ieee80211h || !mode ||
+           mode->mode != HOSTAPD_MODE_IEEE80211A)
+               return 0;
+
+       switch (width) {
+       case CHAN_WIDTH_20_NOHT:
+       case CHAN_WIDTH_20:
+               half_width = 10;
+               break;
+       case CHAN_WIDTH_40:
+               half_width = 20;
+               break;
+       case CHAN_WIDTH_80:
+       case CHAN_WIDTH_80P80:
+               half_width = 40;
+               break;
+       case CHAN_WIDTH_160:
+               half_width = 80;
+               break;
+       default:
+               wpa_printf(MSG_WARNING, "DFS chanwidth %d not supported",
+                          width);
+               return 0;
+       }
+
+       for (i = 0; i < mode->num_channels; i++) {
+               chan = &mode->channels[i];
+
+               if (!(chan->flag & HOSTAPD_CHAN_RADAR))
+                       continue;
+
+               if (center_freq - chan->freq < half_width &&
+                   chan->freq - center_freq < half_width)
+                       res++;
+       }
+
+       wpa_printf(MSG_DEBUG, "DFS: (%d, %d): in range: %s",
+                  center_freq - half_width, center_freq + half_width,
+                  res ? "yes" : "no");
+
+       return res;
+}