Rollup merge of rust-lang#68313 - batrla:master, r=alexcrichton

Options IP_MULTICAST_TTL and IP_MULTICAST_LOOP are 1 byte on BSD

Options IP_MULTICAST_TTL and IP_MULTICAST_LOOP are 1 byte on BSD and Solaris

See ip(4P) man page:
 IP_MULTICAST_TTL     Time  to live for multicast datagrams. This option
                      takes an unsigned character as  an  argument.  Its
                      value  is  the TTL that IP uses on outgoing multi-
                      cast datagrams. The default is 1.

 IP_MULTICAST_LOOP    Loopback for multicast datagrams. Normally  multi-
                      cast  datagrams  are  delivered  to members on the
                      sending  host  (or  sending  zone).  Setting   the
                      unsigned  character argument to 0 causes the oppo-
                      site behavior, meaning that  when  multiple  zones
                      are  present,  the  datagrams are delivered to all
                      zones except the sending zone.

https://docs.oracle.com/cd/E88353_01/html/E37851/ip-4p.html
https://man.openbsd.org/ip.4

src/libstd/sys_common/net.rs

@@ -13,75 +13,43 @@ use crate::time::Duration;
 
 use libc::{c_int, c_void};
 
-#[cfg(not(any(
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "ios",
-    target_os = "macos",
-    target_os = "openbsd",
-    target_os = "netbsd",
-    target_os = "solaris",
-    target_os = "haiku",
-    target_os = "l4re"
-)))]
-use crate::sys::net::netc::IPV6_ADD_MEMBERSHIP;
-#[cfg(not(any(
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "ios",
-    target_os = "macos",
-    target_os = "openbsd",
-    target_os = "netbsd",
-    target_os = "solaris",
-    target_os = "haiku",
-    target_os = "l4re"
-)))]
-use crate::sys::net::netc::IPV6_DROP_MEMBERSHIP;
-#[cfg(any(
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "ios",
-    target_os = "macos",
-    target_os = "openbsd",
-    target_os = "netbsd",
-    target_os = "solaris",
-    target_os = "haiku",
-    target_os = "l4re"
-))]
-use crate::sys::net::netc::IPV6_JOIN_GROUP as IPV6_ADD_MEMBERSHIP;
-#[cfg(any(
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "ios",
-    target_os = "macos",
-    target_os = "openbsd",
-    target_os = "netbsd",
-    target_os = "solaris",
-    target_os = "haiku",
-    target_os = "l4re"
-))]
-use crate::sys::net::netc::IPV6_LEAVE_GROUP as IPV6_DROP_MEMBERSHIP;
-
-#[cfg(any(
-    target_os = "linux",
-    target_os = "android",
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "openbsd",
-    target_os = "netbsd",
-    target_os = "haiku"
-))]
-use libc::MSG_NOSIGNAL;
-#[cfg(not(any(
-    target_os = "linux",
-    target_os = "android",
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "openbsd",
-    target_os = "netbsd",
-    target_os = "haiku"
-)))]
-const MSG_NOSIGNAL: c_int = 0x0;
+cfg_if::cfg_if! {
+    if #[cfg(any(
+        target_os = "dragonfly", target_os = "freebsd",
+        target_os = "ios", target_os = "macos",
+        target_os = "openbsd", target_os = "netbsd",
+        target_os = "solaris", target_os = "haiku", target_os = "l4re"))] {
+        use crate::sys::net::netc::IPV6_JOIN_GROUP as IPV6_ADD_MEMBERSHIP;
+        use crate::sys::net::netc::IPV6_LEAVE_GROUP as IPV6_DROP_MEMBERSHIP;
+    } else {
+        use crate::sys::net::netc::IPV6_ADD_MEMBERSHIP;
+        use crate::sys::net::netc::IPV6_DROP_MEMBERSHIP;
+    }
+}
+
+cfg_if::cfg_if! {
+    if #[cfg(any(
+        target_os = "linux", target_os = "android",
+        target_os = "dragonfly", target_os = "freebsd",
+        target_os = "openbsd", target_os = "netbsd",
+        target_os = "haiku"))] {
+        use libc::MSG_NOSIGNAL;
+    } else {
+        const MSG_NOSIGNAL: c_int = 0x0;
+    }
+}
+
+cfg_if::cfg_if! {
+    if #[cfg(any(
+        target_os = "dragonfly", target_os = "freebsd",
+        target_os = "openbsd", target_os = "netbsd",
+        target_os = "solaris"))] {
+        use libc::c_uchar;
+        type IpV4MultiCastType = c_uchar;
+    } else {
+        type IpV4MultiCastType = c_int;
+    }
+}
 
 ////////////////////////////////////////////////////////////////////////////////
 // sockaddr and misc bindings
@@ -566,20 +534,30 @@ impl UdpSocket {
     }
 
     pub fn set_multicast_loop_v4(&self, multicast_loop_v4: bool) -> io::Result<()> {
-        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_LOOP, multicast_loop_v4 as c_int)
+        setsockopt(
+            &self.inner,
+            c::IPPROTO_IP,
+            c::IP_MULTICAST_LOOP,
+            multicast_loop_v4 as IpV4MultiCastType,
+        )
     }
 
     pub fn multicast_loop_v4(&self) -> io::Result<bool> {
-        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_LOOP)?;
+        let raw: IpV4MultiCastType = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_LOOP)?;
         Ok(raw != 0)
     }
 
     pub fn set_multicast_ttl_v4(&self, multicast_ttl_v4: u32) -> io::Result<()> {
-        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_TTL, multicast_ttl_v4 as c_int)
+        setsockopt(
+            &self.inner,
+            c::IPPROTO_IP,
+            c::IP_MULTICAST_TTL,
+            multicast_ttl_v4 as IpV4MultiCastType,
+        )
     }
 
     pub fn multicast_ttl_v4(&self) -> io::Result<u32> {
-        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_TTL)?;
+        let raw: IpV4MultiCastType = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_TTL)?;
         Ok(raw as u32)
     }