IPv6 on esp8266-nonos-sdk and arduino (#5136)

cores/esp8266/AddrList.h

@@ -0,0 +1,168 @@
+/*
+ AddrList.h - cycle through lwIP netif's ip addresses like a c++ list
+ Copyright (c) 2018 david gauchard.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+/*
+  This class allows to explore all configured IP addresses
+  in lwIP netifs, with that kind of c++ loop:
+
+  for (auto a: ifList)
+    out.printf("IF='%s' index=%d legacy=%d IPv4=%d local=%d hostname='%s' addr= %s\n",
+               a->iface().c_str(),
+               a->number(),
+               a->addr().isLegacy(),
+               a->addr().isV4(),
+               a->addr().isLocal(),
+               a->hostname().c_str(),
+               a->addr().toString().c_str());
+
+  This loop:
+
+      while (WiFi.status() != WL_CONNECTED()) {
+          Serial.print('.');
+          delay(500);
+      }
+
+  can be replaced by:
+
+      for (bool configured = false; !configured; ) {
+          for (auto iface: ifList)
+              if ((configured = !iface->addr().isLocal())
+                  break;
+          Serial.print('.');
+          delay(500);
+      }
+
+  waiting for an IPv6 global address:
+
+      for (bool configured = false; !configured; ) {
+          for (auto iface: ifList)
+              if ((configured = (   !iface->addr()->isV4()
+                                 && !iface->addr().isLocal())))
+                  break;
+          Serial.print('.');
+          delay(500);
+      }
+
+  waiting for an IPv6 global address, on a specific interface:
+
+      for (bool configured = false; !configured; ) {
+          for (auto iface: ifList)
+              if ((configured = (   !iface->addr()->isV4()
+                                 && !iface->addr().isLocal()
+                                 && iface->number() == STATION_IF)))
+                  break;
+          Serial.print('.');
+          delay(500);
+      }
+*/
+
+#ifndef __ADDRLIST_H
+#define __ADDRLIST_H
+
+#include <IPAddress.h>
+#include <lwip/netif.h>
+
+#if LWIP_IPV6
+#define IF_NUM_ADDRESSES (1 + LWIP_IPV6_NUM_ADDRESSES)
+#else
+#define IF_NUM_ADDRESSES (1)
+#endif
+
+
+class AddrListClass {
+
+    // no member in this class
+    // lwIP's global 'struct netif* netif_list' is used
+    // designed to be used with 'for (auto x: ifList)'
+
+    public:
+
+        class const_iterator {
+
+            public:
+
+                // iterator operations:
+
+                const_iterator (bool begin = true): _netif(begin? netif_list: nullptr), _num(-1) { ++*this; }
+                const_iterator (const const_iterator& o): _netif(o._netif), _num(o._num) { }
+                const_iterator& operator= (const const_iterator& o) { _netif = o._netif; _num = o._num; return *this; }
+
+                bool operator!= (const const_iterator& o) { return !equal(o); }
+                bool operator== (const const_iterator& o) { return  equal(o); }
+
+                const_iterator operator++(int) {
+                    const_iterator ret = *this;
+                    ++(*this);
+                    return ret;
+                }
+
+                const_iterator& operator++() {
+                    while (_netif) {
+                        if (++_num == IF_NUM_ADDRESSES) {
+                            _num = -1;
+                            _netif = _netif->next;
+                            continue;
+                        }
+                        if (!ip_addr_isany(_ip_from_netif_num()))
+                            break;
+                    }
+                    return *this;
+                }
+
+                // (*iterator) emulation:
+
+                const const_iterator& operator*  () const { return *this; }
+                const const_iterator* operator-> () const { return  this; }
+
+                bool isLegacy() const { return _num == 0; }
+                bool isLocal() const { return addr().isLocal(); }
+                IPAddress addr () const { return _ip_from_netif_num(); }
+                IPAddress netmask () const { return _netif->netmask; }
+                IPAddress gw () const { return _netif->gw; }
+                String iface () const { return String(_netif->name[0]) + _netif->name[1]; }
+                const char* hostname () const { return _netif->hostname?: emptyString.c_str(); }
+                const char* mac () const { return (const char*)_netif->hwaddr; }
+                int number () const { return _netif->num; }
+
+            protected:
+
+                bool equal (const const_iterator& o) {
+                    return    _netif == o._netif
+                           && (!_netif || _num == o._num);
+                }
+
+                const ip_addr_t* _ip_from_netif_num () const {
+#if LWIP_IPV6
+                    return _num? &_netif->ip6_addr[_num - 1]: &_netif->ip_addr;
+#else
+                    return &_netif->ip_addr;
+#endif
+                }
+
+                netif* _netif;
+                int _num; // address index (0 is legacy, _num-1 is ip6_addr[]'s index)
+        };
+
+        const const_iterator begin () const { return const_iterator(true);  }
+        const const_iterator end   () const { return const_iterator(false); }
+};
+
+extern AddrListClass addrList;
+
+#endif // __ADDRLIST_H