on FreeBSD, on a PF_INET6 socket, recvfrom and friends can actually

return a sockaddr with family PF_INET.  WTF?  Work around that.

array/array_allocate.3

@@ -47,5 +47,11 @@ not enough memory is available.
 array_allocate does \fInot\fR change \fIx\fR to have failed; if you want
 to do that, use array_fail.
 
+.SH PERFORMANCE
+This function can call realloc when the array needs to be enlarged.
+Under exceptional circumstances, this can lead to blocking the current thread.
+It will also zero-fill the newly enlarged part of the array, leading to
+all pages being mapped in by the operating system.  If a small array is
+enlarged to a very large array, this can lead to swapping and blocking.
 .SH "SEE ALSO"
 array_get(3), array_start(3), array_fail(3)

socket/socket_accept6.c

@@ -87,7 +87,7 @@ incoming:
 #endif
 
 #ifdef LIBC_HAS_IP6
-  if (sa.sin6_family==AF_INET) {
+  if (noipv6 || sa.sin6_family==AF_INET || sa.sin6_family==PF_INET) {
     struct sockaddr_in *sa4=(struct sockaddr_in*)&sa;
     if (ip) {
       byte_copy(ip,12,V4mappedprefix);

socket/socket_local6.c

@@ -24,7 +24,7 @@ int socket_local6(int s,char ip[16],uint16 *port,uint32 *scope_id)
 
   if (getsockname(s,(void*) &si,&len) == -1) return winsock2errno(-1);
 #ifdef LIBC_HAS_IP6
-  if (si.sin6_family==AF_INET) {
+  if (noipv6 || si.sin6_family==AF_INET || si.sin6_family==PF_INET) {
     struct sockaddr_in *si4=(void*)&si;
     if (ip) {
       byte_copy(ip,12,V4mappedprefix);

socket/socket_recv6.c

@@ -26,7 +26,7 @@ ssize_t socket_recv6(int s,char *buf,size_t len,char ip[16],uint16 *port,uint32
   if ((r = recvfrom(s,buf,len,0,(struct sockaddr *) &si,&Len))<0) return winsock2errno(-1);
 
 #ifdef LIBC_HAS_IP6
-  if (noipv6) {
+  if (noipv6 || si.sin6_family==AF_INET || si.sin6_family==PF_INET) {
     struct sockaddr_in *si4=(struct sockaddr_in *)&si;
     if (ip) {
       byte_copy(ip,12,V4mappedprefix);

socket/socket_remote6.c

@@ -24,7 +24,7 @@ int socket_remote6(int s,char ip[16],uint16 *port,uint32 *scope_id)
 
   if (getpeername(s,(struct sockaddr *) &si,&len) == -1) return winsock2errno(-1);
 #ifdef LIBC_HAS_IP6
-  if (si.sin6_family==AF_INET) {
+  if (noipv6 || si.sin6_family==AF_INET || si.sin6_family==PF_INET) {
     struct sockaddr_in *si4=(struct sockaddr_in*)&si;
     if (ip) {
       byte_copy(ip,12,V4mappedprefix);