Merge #1611

1611: feature-gate most Nix functions r=rtzoeller a=asomers

Using features reduces build time and size for consumer crates.  By
default all features are enabled.

Co-authored-by: Vincent Dagonneau <vincentdagonneau@gmail.com>
Co-authored-by: Alan Somers <asomers@gmail.com>

1 files changed, 113 insertions, 6 deletions

diff --git a/src/sys/socket/addr.rs b/src/sys/socket/addr.rs
index b119642b..fa62706e 100644
--- a/src/sys/socket/addr.rs
+++ b/src/sys/socket/addr.rs
@@ -13,7 +13,7 @@ use crate::sys::socket::addr::netlink::NetlinkAddr;
 use crate::sys::socket::addr::alg::AlgAddr;
 #[cfg(any(target_os = "ios", target_os = "macos"))]
 use std::os::unix::io::RawFd;
-#[cfg(any(target_os = "ios", target_os = "macos"))]
+#[cfg(all(feature = "ioctl", any(target_os = "ios", target_os = "macos")))]
 use crate::sys::socket::addr::sys_control::SysControlAddr;
 #[cfg(any(target_os = "android",
           target_os = "dragonfly",
@@ -25,6 +25,7 @@ use crate::sys::socket::addr::sys_control::SysControlAddr;
           target_os = "netbsd",
           target_os = "openbsd",
           target_os = "fuchsia"))]
+#[cfg(feature = "net")]
 pub use self::datalink::LinkAddr;
 #[cfg(any(target_os = "android", target_os = "linux"))]
 pub use self::vsock::VsockAddr;
@@ -43,6 +44,7 @@ pub enum AddressFamily {
     Inet6 = libc::AF_INET6,
     /// Kernel user interface device (see [`netlink(7)`](https://man7.org/linux/man-pages/man7/netlink.7.html))
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Netlink = libc::AF_NETLINK,
     /// Low level packet interface (see [`packet(7)`](https://man7.org/linux/man-pages/man7/packet.7.html))
     #[cfg(any(target_os = "android",
@@ -50,84 +52,117 @@ pub enum AddressFamily {
               target_os = "illumos",
               target_os = "fuchsia",
               target_os = "solaris"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Packet = libc::AF_PACKET,
     /// KEXT Controls and Notifications
     #[cfg(any(target_os = "ios", target_os = "macos"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     System = libc::AF_SYSTEM,
     /// Amateur radio AX.25 protocol
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Ax25 = libc::AF_AX25,
     /// IPX - Novell protocols
     Ipx = libc::AF_IPX,
     /// AppleTalk
     AppleTalk = libc::AF_APPLETALK,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     NetRom = libc::AF_NETROM,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Bridge = libc::AF_BRIDGE,
     /// Access to raw ATM PVCs
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     AtmPvc = libc::AF_ATMPVC,
     /// ITU-T X.25 / ISO-8208 protocol (see [`x25(7)`](https://man7.org/linux/man-pages/man7/x25.7.html))
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     X25 = libc::AF_X25,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Rose = libc::AF_ROSE,
     Decnet = libc::AF_DECnet,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     NetBeui = libc::AF_NETBEUI,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Security = libc::AF_SECURITY,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Key = libc::AF_KEY,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Ash = libc::AF_ASH,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Econet = libc::AF_ECONET,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     AtmSvc = libc::AF_ATMSVC,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Rds = libc::AF_RDS,
     Sna = libc::AF_SNA,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Irda = libc::AF_IRDA,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Pppox = libc::AF_PPPOX,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Wanpipe = libc::AF_WANPIPE,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Llc = libc::AF_LLC,
     #[cfg(target_os = "linux")]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Ib = libc::AF_IB,
     #[cfg(target_os = "linux")]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Mpls = libc::AF_MPLS,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Can = libc::AF_CAN,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Tipc = libc::AF_TIPC,
     #[cfg(not(any(target_os = "illumos",
                   target_os = "ios",
                   target_os = "macos",
                   target_os = "solaris")))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Bluetooth = libc::AF_BLUETOOTH,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Iucv = libc::AF_IUCV,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     RxRpc = libc::AF_RXRPC,
     #[cfg(not(any(target_os = "illumos", target_os = "solaris")))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Isdn = libc::AF_ISDN,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Phonet = libc::AF_PHONET,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Ieee802154 = libc::AF_IEEE802154,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Caif = libc::AF_CAIF,
     /// Interface to kernel crypto API
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Alg = libc::AF_ALG,
     #[cfg(target_os = "linux")]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Nfc = libc::AF_NFC,
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Vsock = libc::AF_VSOCK,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -135,6 +170,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     ImpLink = libc::AF_IMPLINK,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -142,6 +178,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Pup = libc::AF_PUP,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -149,11 +186,13 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Chaos = libc::AF_CHAOS,
     #[cfg(any(target_os = "ios",
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Ns = libc::AF_NS,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -161,6 +200,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Iso = libc::AF_ISO,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -168,6 +208,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Datakit = libc::AF_DATAKIT,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -175,6 +216,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Ccitt = libc::AF_CCITT,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -182,6 +224,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Dli = libc::AF_DLI,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -189,6 +232,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Lat = libc::AF_LAT,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -196,6 +240,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Hylink = libc::AF_HYLINK,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -204,6 +249,7 @@ pub enum AddressFamily {
               target_os = "illumos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Link = libc::AF_LINK,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -211,6 +257,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Coip = libc::AF_COIP,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -218,6 +265,7 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Cnt = libc::AF_CNT,
     #[cfg(any(target_os = "dragonfly",
               target_os = "freebsd",
@@ -225,9 +273,11 @@ pub enum AddressFamily {
               target_os = "macos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Natm = libc::AF_NATM,
     /// Unspecified address family, (see [`getaddrinfo(3)`](https://man7.org/linux/man-pages/man3/getaddrinfo.3.html))
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Unspec = libc::AF_UNSPEC,
 }
 
@@ -263,6 +313,9 @@ impl AddressFamily {
     }
 }
 
+feature! {
+#![feature = "net"]
+
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
 pub enum InetAddr {
     V4(libc::sockaddr_in),
@@ -515,6 +568,7 @@ impl fmt::Display for Ipv6Addr {
         self.to_std().fmt(fmt)
     }
 }
+}
 
 /// A wrapper around `sockaddr_un`.
 #[derive(Clone, Copy, Debug)]
@@ -586,6 +640,7 @@ impl UnixAddr {
     /// This is a Linux-specific extension, primarily used to allow chrooted
     /// processes to communicate with processes having a different filesystem view.
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     pub fn new_abstract(path: &[u8]) -> Result<UnixAddr> {
         unsafe {
             let mut ret = libc::sockaddr_un {
@@ -644,6 +699,7 @@ impl UnixAddr {
     /// For abstract sockets only the bare name is returned, without the
     /// leading null byte. `None` is returned for unnamed or path-backed sockets.
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     pub fn as_abstract(&self) -> Option<&[u8]> {
         match self.kind() {
             UnixAddrKind::Abstract(name) => Some(name),
@@ -709,13 +765,18 @@ impl Hash for UnixAddr {
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
 #[non_exhaustive]
 pub enum SockAddr {
+    #[cfg(feature = "net")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "net")))]
     Inet(InetAddr),
     Unix(UnixAddr),
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Netlink(NetlinkAddr),
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Alg(AlgAddr),
-    #[cfg(any(target_os = "ios", target_os = "macos"))]
+    #[cfg(all(feature = "ioctl", any(target_os = "ios", target_os = "macos")))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "ioctl")))]
     SysControl(SysControlAddr),
     /// Datalink address (MAC)
     #[cfg(any(target_os = "android",
@@ -727,52 +788,68 @@ pub enum SockAddr {
               target_os = "illumos",
               target_os = "netbsd",
               target_os = "openbsd"))]
+    #[cfg(feature = "net")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "net")))]
     Link(LinkAddr),
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     Vsock(VsockAddr),
 }
 
 impl SockAddr {
+    feature! {
+    #![feature = "net"]
     pub fn new_inet(addr: InetAddr) -> SockAddr {
         SockAddr::Inet(addr)
     }
+    }
 
     pub fn new_unix<P: ?Sized + NixPath>(path: &P) -> Result<SockAddr> {
         Ok(SockAddr::Unix(UnixAddr::new(path)?))
     }
 
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     pub fn new_netlink(pid: u32, groups: u32) -> SockAddr {
         SockAddr::Netlink(NetlinkAddr::new(pid, groups))
     }
 
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     pub fn new_alg(alg_type: &str, alg_name: &str) -> SockAddr {
         SockAddr::Alg(AlgAddr::new(alg_type, alg_name))
     }
 
+    feature! {
+    #![feature = "ioctl"]
     #[cfg(any(target_os = "ios", target_os = "macos"))]
     pub fn new_sys_control(sockfd: RawFd, name: &str, unit: u32) -> Result<SockAddr> {
         SysControlAddr::from_name(sockfd, name, unit).map(SockAddr::SysControl)
     }
+    }
 
     #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
     pub fn new_vsock(cid: u32, port: u32) -> SockAddr {
         SockAddr::Vsock(VsockAddr::new(cid, port))
     }
 
     pub fn family(&self) -> AddressFamily {
         match *self {
+            #[cfg(feature = "net")]
             SockAddr::Inet(InetAddr::V4(..)) => AddressFamily::Inet,
+            #[cfg(feature = "net")]
             SockAddr::Inet(InetAddr::V6(..)) => AddressFamily::Inet6,
             SockAddr::Unix(..) => AddressFamily::Unix,
             #[cfg(any(target_os = "android", target_os = "linux"))]
             SockAddr::Netlink(..) => AddressFamily::Netlink,
             #[cfg(any(target_os = "android", target_os = "linux"))]
             SockAddr::Alg(..) => AddressFamily::Alg,
-            #[cfg(any(target_os = "ios", target_os = "macos"))]
+            #[cfg(all(feature = "ioctl",
+                      any(target_os = "ios", target_os = "macos")))]
             SockAddr::SysControl(..) => AddressFamily::System,
             #[cfg(any(target_os = "android", target_os = "linux"))]
+            #[cfg(feature = "net")]
             SockAddr::Link(..) => AddressFamily::Packet,
             #[cfg(any(target_os = "dragonfly",
                       target_os = "freebsd",
@@ -781,6 +858,7 @@ impl SockAddr {
                       target_os = "netbsd",
                       target_os = "illumos",
                       target_os = "openbsd"))]
+            #[cfg(feature = "net")]
             SockAddr::Link(..) => AddressFamily::Link,
             #[cfg(any(target_os = "android", target_os = "linux"))]
             SockAddr::Vsock(..) => AddressFamily::Vsock,
@@ -802,23 +880,28 @@ impl SockAddr {
     /// unsafe because it takes a raw pointer as argument.  The caller must
     /// ensure that the pointer is valid.
     #[cfg(not(target_os = "fuchsia"))]
+    #[cfg(feature = "net")]
     pub(crate) unsafe fn from_libc_sockaddr(addr: *const libc::sockaddr) -> Option<SockAddr> {
         if addr.is_null() {
             None
         } else {
             match AddressFamily::from_i32(i32::from((*addr).sa_family)) {
                 Some(AddressFamily::Unix) => None,
+                #[cfg(feature = "net")]
                 Some(AddressFamily::Inet) => Some(SockAddr::Inet(
                     InetAddr::V4(*(addr as *const libc::sockaddr_in)))),
+                #[cfg(feature = "net")]
                 Some(AddressFamily::Inet6) => Some(SockAddr::Inet(
                     InetAddr::V6(*(addr as *const libc::sockaddr_in6)))),
                 #[cfg(any(target_os = "android", target_os = "linux"))]
                 Some(AddressFamily::Netlink) => Some(SockAddr::Netlink(
                     NetlinkAddr(*(addr as *const libc::sockaddr_nl)))),
-                #[cfg(any(target_os = "ios", target_os = "macos"))]
+                #[cfg(all(feature = "ioctl",
+                          any(target_os = "ios", target_os = "macos")))]
                 Some(AddressFamily::System) => Some(SockAddr::SysControl(
                     SysControlAddr(*(addr as *const libc::sockaddr_ctl)))),
                 #[cfg(any(target_os = "android", target_os = "linux"))]
+                #[cfg(feature = "net")]
                 Some(AddressFamily::Packet) => Some(SockAddr::Link(
                     LinkAddr(*(addr as *const libc::sockaddr_ll)))),
                 #[cfg(any(target_os = "dragonfly",
@@ -828,6 +911,7 @@ impl SockAddr {
                           target_os = "netbsd",
                           target_os = "illumos",
                           target_os = "openbsd"))]
+                #[cfg(feature = "net")]
                 Some(AddressFamily::Link) => {
                     let ether_addr = LinkAddr(*(addr as *const libc::sockaddr_dl));
                     if ether_addr.is_empty() {
@@ -855,6 +939,7 @@ impl SockAddr {
     /// a sockaddr * need to take the size of the underlying type as well and then internally cast it back.
     pub fn as_ffi_pair(&self) -> (&libc::sockaddr, libc::socklen_t) {
         match *self {
+            #[cfg(feature = "net")]
             SockAddr::Inet(InetAddr::V4(ref addr)) => (
                 // This cast is always allowed in C
                 unsafe {
@@ -862,6 +947,7 @@ impl SockAddr {
                 },
                 mem::size_of_val(addr) as libc::socklen_t
             ),
+            #[cfg(feature = "net")]
             SockAddr::Inet(InetAddr::V6(ref addr)) => (
                 // This cast is always allowed in C
                 unsafe {
@@ -892,7 +978,8 @@ impl SockAddr {
                 },
                 mem::size_of_val(sa) as libc::socklen_t
             ),
-            #[cfg(any(target_os = "ios", target_os = "macos"))]
+            #[cfg(all(feature = "ioctl",
+                      any(target_os = "ios", target_os = "macos")))]
             SockAddr::SysControl(SysControlAddr(ref sa)) => (
                 // This cast is always allowed in C
                 unsafe {
@@ -902,6 +989,7 @@ impl SockAddr {
 
             ),
             #[cfg(any(target_os = "android", target_os = "linux"))]
+            #[cfg(feature = "net")]
             SockAddr::Link(LinkAddr(ref addr)) => (
                 // This cast is always allowed in C
                 unsafe {
@@ -916,6 +1004,7 @@ impl SockAddr {
                       target_os = "illumos",
                       target_os = "netbsd",
                       target_os = "openbsd"))]
+            #[cfg(feature = "net")]
             SockAddr::Link(LinkAddr(ref addr)) => (
                 // This cast is always allowed in C
                 unsafe {
@@ -938,13 +1027,15 @@ impl SockAddr {
 impl fmt::Display for SockAddr {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match *self {
+            #[cfg(feature = "net")]
             SockAddr::Inet(ref inet) => inet.fmt(f),
             SockAddr::Unix(ref unix) => unix.fmt(f),
             #[cfg(any(target_os = "android", target_os = "linux"))]
             SockAddr::Netlink(ref nl) => nl.fmt(f),
             #[cfg(any(target_os = "android", target_os = "linux"))]
             SockAddr::Alg(ref nl) => nl.fmt(f),
-            #[cfg(any(target_os = "ios", target_os = "macos"))]
+            #[cfg(all(feature = "ioctl",
+                      any(target_os = "ios", target_os = "macos")))]
             SockAddr::SysControl(ref sc) => sc.fmt(f),
             #[cfg(any(target_os = "android",
                       target_os = "dragonfly",
@@ -955,6 +1046,7 @@ impl fmt::Display for SockAddr {
                       target_os = "netbsd",
                       target_os = "illumos",
                       target_os = "openbsd"))]
+            #[cfg(feature = "net")]
             SockAddr::Link(ref ether_addr) => ether_addr.fmt(f),
             #[cfg(any(target_os = "android", target_os = "linux"))]
             SockAddr::Vsock(ref svm) => svm.fmt(f),
@@ -963,6 +1055,7 @@ impl fmt::Display for SockAddr {
 }
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
 pub mod netlink {
     use crate::sys::socket::addr::AddressFamily;
     use libc::{sa_family_t, sockaddr_nl};
@@ -998,6 +1091,7 @@ pub mod netlink {
 }
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
 pub mod alg {
     use libc::{AF_ALG, sockaddr_alg, c_char};
     use std::{fmt, mem, str};
@@ -1060,6 +1154,8 @@ pub mod alg {
     }
 }
 
+feature! {
+#![feature = "ioctl"]
 #[cfg(any(target_os = "ios", target_os = "macos"))]
 pub mod sys_control {
     use crate::sys::socket::addr::AddressFamily;
@@ -1130,10 +1226,14 @@ pub mod sys_control {
         }
     }
 }
+}
 
 
 #[cfg(any(target_os = "android", target_os = "linux", target_os = "fuchsia"))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
 mod datalink {
+    feature! {
+    #![feature = "net"]
     use super::{fmt, AddressFamily};
 
     /// Hardware Address
@@ -1197,6 +1297,7 @@ mod datalink {
                 addr[5])
         }
     }
+    }
 }
 
 #[cfg(any(target_os = "dragonfly",
@@ -1206,7 +1307,10 @@ mod datalink {
           target_os = "illumos",
           target_os = "netbsd",
           target_os = "openbsd"))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
 mod datalink {
+    feature! {
+    #![feature = "net"]
     use super::{fmt, AddressFamily};
 
     /// Hardware Address
@@ -1216,6 +1320,7 @@ mod datalink {
     impl LinkAddr {
         /// Total length of sockaddr
         #[cfg(not(target_os = "illumos"))]
+        #[cfg_attr(docsrs, doc(cfg(all())))]
         pub fn len(&self) -> usize {
             self.0.sdl_len as usize
         }
@@ -1291,9 +1396,11 @@ mod datalink {
                 addr[5])
         }
     }
+    }
 }
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
 pub mod vsock {
     use crate::sys::socket::addr::AddressFamily;
     use libc::{sa_family_t, sockaddr_vm};