# fallback for old Android

Changes on non-Windows platforms:
- Deprecated gethostbyname() has been replaced by getifaddrs()+inet_ntop() handling IPv4+IPv6 addresses;
- External IPs are now preferred comparing to dummy localhost 127.0.0.1.

src/OSD/OSD_Host.cxx

@@ -21,10 +21,24 @@
 #include <Standard_NullObject.hxx>
 #include <TCollection_AsciiString.hxx>
 
-const OSD_WhoAmI Iam = OSD_WHost;
-
 #include <errno.h>
 
+#ifndef HAVE_IFADDRS
+  #if defined(__ANDROID__)
+    #include <android/api-level.h>
+    #if (__ANDROID_API__ >= 24)
+      #define HAVE_IFADDRS
+    #endif
+  #else
+    #define HAVE_IFADDRS
+  #endif
+#endif
+
+#include <arpa/inet.h>
+#ifdef HAVE_IFADDRS
+  #include <ifaddrs.h>
+#endif
+
 #include <sys/utsname.h> // For 'uname'
 #include <netdb.h>       // This is for 'gethostbyname'
 #include <unistd.h>
@@ -89,7 +103,7 @@ char value[65];
 int status;
 
 status = gethostname(value, 64);
-if (status == -1) myError.SetValue(errno, Iam, "Host Name");
+if (status == -1) myError.SetValue(errno, OSD_WHost, "Host Name");
 
  result = value;
  return(result);
@@ -116,25 +130,67 @@ Standard_Integer OSD_Host::AvailableMemory(){
 
 // =========================================================================
 
-TCollection_AsciiString OSD_Host::InternetAddress(){
- struct hostent internet_address;
- int a,b,c,d;
- char buffer[16];
- TCollection_AsciiString result,host;
+TCollection_AsciiString OSD_Host::InternetAddress()
+{
+  TCollection_AsciiString aResult;
+#ifdef HAVE_IFADDRS
+  struct ifaddrs* anAddrFullInfo = NULL;
+  getifaddrs (&anAddrFullInfo);
+  for (struct ifaddrs* anAddrIter = anAddrFullInfo; anAddrIter != NULL; anAddrIter = anAddrIter->ifa_next)
+  {
+    if (!anAddrIter->ifa_addr)
+    {
+      continue;
+    }
 
- host = HostName();
- memcpy(&internet_address,
-        gethostbyname(host.ToCString()),
-        sizeof(struct hostent));
-
- // Gets each bytes into integers
- a = (unsigned char)internet_address.h_addr_list[0][0];
- b = (unsigned char)internet_address.h_addr_list[0][1];
- c = (unsigned char)internet_address.h_addr_list[0][2];
- d = (unsigned char)internet_address.h_addr_list[0][3];
- sprintf(buffer,"%d.%d.%d.%d",a,b,c,d);
- result = buffer;
- return(result);
+    if (anAddrIter->ifa_addr->sa_family == AF_INET)
+    {
+      // IP4 Address
+      char aBuffer[INET_ADDRSTRLEN];
+      void* aTmpAddrPtr = &((struct sockaddr_in* )anAddrIter->ifa_addr)->sin_addr;
+      inet_ntop (AF_INET, aTmpAddrPtr, aBuffer, sizeof(aBuffer));
+      if (strcmp (aBuffer, "127.0.0.1") != 0) // skip localhost address
+      {
+        aResult = aBuffer;
+        break;
+      }
+    }
+    else if (anAddrIter->ifa_addr->sa_family == AF_INET6)
+    {
+      // IP6 Address
+      char aBuffer[INET6_ADDRSTRLEN];
+      void* aTmpAddrPtr = &((struct sockaddr_in6 *)anAddrIter->ifa_addr)->sin6_addr;
+      inet_ntop (AF_INET6, aTmpAddrPtr, aBuffer, sizeof(aBuffer));
+      if (strcmp (aBuffer, "::1") != 0) // skip localhost address
+      {
+        aResult = aBuffer;
+        break;
+      }
+    }
+  }
+  if (anAddrFullInfo != NULL)
+  {
+    freeifaddrs (anAddrFullInfo);
+  }
+#else
+  // fallback for ancient systems
+  const TCollection_AsciiString aHost = HostName();
+  if (struct hostent* anAddr = gethostbyname (aHost.ToCString()))
+  {
+    char aBuffer[16];
+    const int a = (unsigned char)anAddr->h_addr_list[0][0];
+    const int b = (unsigned char)anAddr->h_addr_list[0][1];
+    const int c = (unsigned char)anAddr->h_addr_list[0][2];
+    const int d = (unsigned char)anAddr->h_addr_list[0][3];
+    sprintf (aBuffer, "%d.%d.%d.%d", a, b, c, d);
+    aResult = aBuffer;
+  }
+#endif
+  if (aResult.IsEmpty())
+  {
+    return "127.0.0.1";
+  }
+  return aResult;
 }
 
 // =========================================================================

src/STEPConstruct/STEPConstruct_AP203Context.cxx

@@ -164,12 +164,20 @@ Handle(StepBasic_PersonAndOrganization) STEPConstruct_AP203Context::DefaultPerso
     OSD_Host aHost;
     TCollection_AsciiString anIP = aHost.InternetAddress();
     // cut off last number
-    Standard_Integer aLastDotIndex = anIP.SearchFromEnd (".");
-    if (aLastDotIndex >0)
+    const Standard_Integer aLastDotIndex = anIP.SearchFromEnd (".");
+    if (aLastDotIndex > 0)
     {
+      // IPv4
       anIP.Trunc (aLastDotIndex - 1);
       orgId->AssignCat (anIP.ToCString());
     }
+    else
+    {
+      // IPv6
+      const Standard_Integer aLastColonIndex = anIP.SearchFromEnd (":");
+      anIP.Trunc (aLastColonIndex - 1);
+      orgId->AssignCat (anIP.ToCString());
+    }
     
     // create organization
     Handle(StepBasic_Organization) aOrg = new StepBasic_Organization;