Import lwIP contrib rep

... from http://git.savannah.gnu.org/cgit/lwip/lwip-contrib.git/ into contrib/ subdir, STABLE-2_1_0_RELEASE tag
lwIP contrib is now officially frozen
TODO: Fix build

contrib/ports/win32/pcapif_helper.c

@@ -0,0 +1,105 @@
+/**
+ * pcapif_helper.c - This file is part of lwIP pcapif and provides helper functions
+ * for managing the link state.
+ */
+
+#include "pcapif_helper.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "lwip/arch.h"
+
+#ifdef WIN32
+
+#define WIN32_LEAN_AND_MEAN
+
+#ifdef _MSC_VER
+#pragma warning( push, 3 )
+#endif
+#include <windows.h>
+#include <packet32.h>
+#include <ntddndis.h>
+#ifdef _MSC_VER
+#pragma warning ( pop )
+#endif
+
+struct pcapifh_linkstate {
+  LPADAPTER        lpAdapter;
+  PPACKET_OID_DATA ppacket_oid_data;
+};
+
+struct pcapifh_linkstate* pcapifh_linkstate_init(char *adapter_name)
+{
+  struct pcapifh_linkstate* state = (struct pcapifh_linkstate*)malloc(sizeof(struct pcapifh_linkstate));
+  if (state != NULL) {
+    memset(state, 0, sizeof(struct pcapifh_linkstate));
+    state->ppacket_oid_data = (PPACKET_OID_DATA)malloc(sizeof(PACKET_OID_DATA) + sizeof(NDIS_MEDIA_STATE));
+    if (state->ppacket_oid_data == NULL) {
+      free(state);
+      state = NULL;
+    } else {
+      state->lpAdapter = PacketOpenAdapter((char*)adapter_name);
+      if ((state->lpAdapter == NULL) || (state->lpAdapter->hFile == INVALID_HANDLE_VALUE)) {
+        /* failed to open adapter */
+        free(state);
+        state = NULL;
+      }
+    }
+  }
+  return state;
+}
+
+enum pcapifh_link_event pcapifh_linkstate_get(struct pcapifh_linkstate* state)
+{
+  enum pcapifh_link_event ret = PCAPIF_LINKEVENT_UNKNOWN;
+  if (state != NULL) {
+    state->ppacket_oid_data->Oid    = OID_GEN_MEDIA_CONNECT_STATUS;
+    state->ppacket_oid_data->Length = sizeof(NDIS_MEDIA_STATE);
+    if (PacketRequest(state->lpAdapter, FALSE, state->ppacket_oid_data)) {
+      NDIS_MEDIA_STATE fNdisMediaState;
+      fNdisMediaState = (*((PNDIS_MEDIA_STATE)(state->ppacket_oid_data->Data)));
+      ret = ((fNdisMediaState == NdisMediaStateConnected) ? PCAPIF_LINKEVENT_UP : PCAPIF_LINKEVENT_DOWN);
+    }
+  }
+  return ret;
+}
+
+void pcapifh_linkstate_close(struct pcapifh_linkstate* state)
+{
+  if (state != NULL) {
+    if (state->lpAdapter != NULL) {
+      PacketCloseAdapter(state->lpAdapter);
+    }
+    if (state->ppacket_oid_data != NULL) {
+      free(state->ppacket_oid_data);
+    }
+    free(state);
+  }
+}
+
+#else /* WIN32 */
+
+/* @todo: add linux/unix implementation? */
+
+struct pcapifh_linkstate {
+  u8_t empty;
+};
+
+struct pcapifh_linkstate* pcapifh_linkstate_init(char *adapter_name)
+{
+  LWIP_UNUSED_ARG(adapter_name);
+  return NULL;
+}
+
+enum pcapifh_link_event pcapifh_linkstate_get(struct pcapifh_linkstate* state)
+{
+  LWIP_UNUSED_ARG(state);
+  return PCAPIF_LINKEVENT_UP;
+}
+void pcapifh_linkstate_close(struct pcapifh_linkstate* state)
+{
+  LWIP_UNUSED_ARG(state);
+}
+
+#endif /* WIN32 */