refactor(network): wait for new address

src/main.cpp

@@ -15,7 +15,7 @@ int main(int argc, char* argv[])
     waybar::client = &c;
     std::signal(SIGUSR1, [] (int /*signal*/) {
       for (auto& bar : waybar::client->bars) {
-        (*bar).toggle();
+        bar->toggle();
       }
     });
 

src/modules/battery.cpp

@@ -101,7 +101,7 @@ const std::string waybar::modules::Battery::getState(uint8_t capacity) const
     return a.second < b.second;
   });
   std::string valid_state;
-  for (auto state : states) {
+  for (auto const& state : states) {
     if (capacity <= state.second && valid_state.empty()) {
       label_.get_style_context()->add_class(state.first);
       valid_state = state.first;

src/modules/network.cpp

@@ -50,6 +50,7 @@ void waybar::modules::Network::worker()
     uint64_t len = netlinkResponse(sock_fd_, buf, sizeof(buf),
       RTMGRP_LINK | RTMGRP_IPV4_IFADDR);
     bool need_update = false;
+    bool new_addr = false;
     for (auto nh = reinterpret_cast<struct nlmsghdr *>(buf); NLMSG_OK(nh, len);
       nh = NLMSG_NEXT(nh, len)) {
       if (nh->nlmsg_type == NLMSG_DONE) {
@@ -58,6 +59,9 @@ void waybar::modules::Network::worker()
       if (nh->nlmsg_type == NLMSG_ERROR) {
         continue;
       }
+      if (nh->nlmsg_type == RTM_NEWADDR) {
+        new_addr = true;
+      }
       if (nh->nlmsg_type < RTM_NEWADDR) {
         auto rtif = static_cast<struct ifinfomsg *>(NLMSG_DATA(nh));
         if (rtif->ifi_index == static_cast<int>(ifid_)) {
@@ -69,9 +73,15 @@ void waybar::modules::Network::worker()
       }
     }
     if (ifid_ <= 0 && !config_["interface"].isString()) {
-      // Need to wait before get external interface
-      thread_.sleep_for(std::chrono::seconds(1));
-      ifid_ = getExternalInterface();
+      if (new_addr) {
+        // Need to wait before get external interface
+        while (ifid_ <= 0) {
+          ifid_ = getExternalInterface();
+          thread_.sleep_for(std::chrono::seconds(1));
+        }
+      } else {
+        ifid_ = getExternalInterface();
+      }
       if (ifid_ > 0) {
         char ifname[IF_NAMESIZE];
         if_indextoname(ifid_, ifname);
@@ -319,13 +329,12 @@ int waybar::modules::Network::netlinkRequest(int fd, void *req,
 int waybar::modules::Network::netlinkResponse(int fd, void *resp,
   uint32_t resplen, uint32_t groups)
 {
-  int ret;
   struct sockaddr_nl sa = {};
   sa.nl_family = AF_NETLINK;
   sa.nl_groups = groups;
   struct iovec iov = { resp, resplen };
   struct msghdr msg = { &sa, sizeof(sa), &iov, 1, nullptr, 0, 0 };
-  ret = recvmsg(fd, &msg, 0);
+  auto ret = recvmsg(fd, &msg, 0);
   if (msg.msg_flags & MSG_TRUNC) {
     return -1;
   }