platform: rework initialization of wifi frequencies

Iterate only once over the netlink array, and realloc the buffer when
needed.

1 files changed, 14 insertions, 25 deletions

diff --git a/src/libnm-platform/wifi/nm-wifi-utils-nl80211.c b/src/libnm-platform/wifi/nm-wifi-utils-nl80211.c
index b7e5c45af8..b064ff2942 100644
--- a/src/libnm-platform/wifi/nm-wifi-utils-nl80211.c
+++ b/src/libnm-platform/wifi/nm-wifi-utils-nl80211.c
@@ -601,7 +601,7 @@ nl80211_wiphy_info_handler(struct nl_msg *msg, void *arg)
     struct nlattr              *nl_freq;
     int                         rem_freq;
     int                         rem_band;
-    int                         freq_idx;
+    guint                       num_alloc;
 
 #ifdef NL80211_FREQUENCY_ATTR_NO_IR
     G_STATIC_ASSERT_EXPR(NL80211_FREQUENCY_ATTR_PASSIVE_SCAN == NL80211_FREQUENCY_ATTR_NO_IR
@@ -655,28 +655,11 @@ nl80211_wiphy_info_handler(struct nl_msg *msg, void *arg)
         }
     }
 
-    /* Find number of supported frequencies */
-    info->num_freqs = 0;
-
-    nla_for_each_nested (nl_band, tb[NL80211_ATTR_WIPHY_BANDS], rem_band) {
-        if (nla_parse_nested_arr(tb_band, nl_band, NULL) < 0)
-            return NL_SKIP;
-
-        nla_for_each_nested (nl_freq, tb_band[NL80211_BAND_ATTR_FREQS], rem_freq) {
-            if (nla_parse_nested_arr(tb_freq, nl_freq, freq_policy) < 0)
-                continue;
-
-            if (!tb_freq[NL80211_FREQUENCY_ATTR_FREQ])
-                continue;
-
-            info->num_freqs++;
-        }
-    }
-
     /* Read supported frequencies */
-    info->freqs = g_malloc0(sizeof(guint32) * info->num_freqs);
+    num_alloc       = 32;
+    info->num_freqs = 0;
+    info->freqs     = g_new(guint32, num_alloc);
 
-    freq_idx = 0;
     nla_for_each_nested (nl_band, tb[NL80211_ATTR_WIPHY_BANDS], rem_band) {
         if (nla_parse_nested_arr(tb_band, nl_band, NULL) < 0)
             return NL_SKIP;
@@ -688,19 +671,25 @@ nl80211_wiphy_info_handler(struct nl_msg *msg, void *arg)
             if (!tb_freq[NL80211_FREQUENCY_ATTR_FREQ])
                 continue;
 
-            info->freqs[freq_idx] = nla_get_u32(tb_freq[NL80211_FREQUENCY_ATTR_FREQ]);
+            if (info->num_freqs >= num_alloc) {
+                num_alloc *= 2;
+                info->freqs = g_renew(guint32, info->freqs, num_alloc);
+            }
 
+            info->freqs[info->num_freqs] = nla_get_u32(tb_freq[NL80211_FREQUENCY_ATTR_FREQ]);
             info->caps |= _NM_WIFI_DEVICE_CAP_FREQ_VALID;
 
-            if (info->freqs[freq_idx] > 2400 && info->freqs[freq_idx] < 2500)
+            if (info->freqs[info->num_freqs] > 2400 && info->freqs[info->num_freqs] < 2500)
                 info->caps |= _NM_WIFI_DEVICE_CAP_FREQ_2GHZ;
-            if (info->freqs[freq_idx] > 4900 && info->freqs[freq_idx] < 6000)
+            if (info->freqs[info->num_freqs] > 4900 && info->freqs[info->num_freqs] < 6000)
                 info->caps |= _NM_WIFI_DEVICE_CAP_FREQ_5GHZ;
 
-            freq_idx++;
+            info->num_freqs++;
         }
     }
 
+    info->freqs = g_renew(guint32, info->freqs, info->num_freqs);
+
     /* Read security/encryption support */
     if (tb[NL80211_ATTR_CIPHER_SUITES]) {
         guint32 *ciphers = nla_data(tb[NL80211_ATTR_CIPHER_SUITES]);