6 files changed, 99 insertions, 7 deletions
diff --git a/libc/src/unix/bsd/freebsdlike/dragonfly/mod.rs b/libc/src/unix/bsd/freebsdlike/dragonfly/mod.rs
index 41b6956..992d008 100644
--- a/libc/src/unix/bsd/freebsdlike/dragonfly/mod.rs
+++ b/libc/src/unix/bsd/freebsdlike/dragonfly/mod.rs
@@ -210,6 +210,12 @@ s! {
         pub sdl_rcf: ::c_ushort,
         pub sdl_route: [::c_ushort; 16],
     }
+
+    pub struct stack_t {
+        pub ss_sp: *mut ::c_char,
+        pub ss_size: ::size_t,
+        pub ss_flags: ::c_int,
+    }
 }
 
 pub const RAND_MAX: ::c_int = 0x7fff_ffff;
@@ -782,6 +788,39 @@ pub const SF_NOHISTORY: ::c_ulong = 0x00400000;
 pub const SF_CACHE:     ::c_ulong = 0x00800000;
 pub const SF_XLINK:     ::c_ulong = 0x01000000;
 
+fn _CMSG_ALIGN(n: usize) -> usize {
+    (n + 3) & !3
+}
+
+f! {
+    pub fn CMSG_DATA(cmsg: *const ::cmsghdr) -> *mut ::c_uchar {
+        (cmsg as *mut ::c_uchar)
+            .offset(_CMSG_ALIGN(mem::size_of::<::cmsghdr>()) as isize)
+    }
+
+    pub fn CMSG_LEN(length: ::c_uint) -> ::c_uint {
+        _CMSG_ALIGN(mem::size_of::<::cmsghdr>()) + length as usize
+    }
+
+    pub fn CMSG_NXTHDR(mhdr: *const ::msghdr, cmsg: *const ::cmsghdr)
+        -> *mut ::cmsghdr
+    {
+        let next = cmsg as usize + _CMSG_ALIGN((*cmsg).cmsg_len)
+            + _CMSG_ALIGN(mem::size_of::<::cmsghdr>());
+        let max = (*mhdr).msg_control as usize
+            + (*mhdr).msg_controllen as usize;
+        if next <= max {
+            (cmsg as usize + _CMSG_ALIGN((*cmsg).cmsg_len)) as *mut ::cmsghdr
+        } else {
+            0 as *mut ::cmsghdr
+        }
+    }
+
+    pub fn CMSG_SPACE(length: ::c_uint) -> ::c_uint {
+        _CMSG_ALIGN(mem::size_of::<::cmsghdr>()) + _CMSG_ALIGN(length as usize)
+    }
+}
+
 extern {
     pub fn mprotect(addr: *mut ::c_void, len: ::size_t, prot: ::c_int)
                     -> ::c_int;
diff --git a/libc/src/unix/bsd/freebsdlike/freebsd/aarch64.rs b/libc/src/unix/bsd/freebsdlike/freebsd/aarch64.rs
index 3d61f88..d33b475 100644
--- a/libc/src/unix/bsd/freebsdlike/freebsd/aarch64.rs
+++ b/libc/src/unix/bsd/freebsdlike/freebsd/aarch64.rs
@@ -1,3 +1,5 @@
+use dox::mem;
+
 pub type c_long = i64;
 pub type c_ulong = u64;
 pub type time_t = i64;
@@ -29,4 +31,7 @@ s! {
     }
 }
 
+// should be pub(crate), but that requires Rust 1.18.0
+#[doc(hidden)]
+pub const _ALIGNBYTES: usize = mem::size_of::<::c_longlong>() - 1;
 pub const MAP_32BIT: ::c_int = 0x00080000;
diff --git a/libc/src/unix/bsd/freebsdlike/freebsd/mod.rs b/libc/src/unix/bsd/freebsdlike/freebsd/mod.rs
index 878deea..91eab30 100644
--- a/libc/src/unix/bsd/freebsdlike/freebsd/mod.rs
+++ b/libc/src/unix/bsd/freebsdlike/freebsd/mod.rs
@@ -1,3 +1,5 @@
+use dox::mem;
+
 pub type fflags_t = u32;
 pub type clock_t = i32;
 pub type ino_t = u32;
@@ -182,6 +184,12 @@ s! {
         pub sdl_slen: ::c_uchar,
         pub sdl_data: [::c_char; 46],
     }
+
+    pub struct stack_t {
+        pub ss_sp: *mut ::c_void,
+        pub ss_size: ::size_t,
+        pub ss_flags: ::c_int,
+    }
 }
 
 pub const SIGEV_THREAD_ID: ::c_int = 4;
@@ -962,7 +970,43 @@ pub const UF_READONLY:  ::c_ulong = 0x00001000;
 pub const UF_HIDDEN:    ::c_ulong = 0x00008000;
 pub const SF_SNAPSHOT:  ::c_ulong = 0x00200000;
 
+fn _ALIGN(p: usize) -> usize {
+    (p + _ALIGNBYTES) & !_ALIGNBYTES
+}
+
 f! {
+    pub fn CMSG_DATA(cmsg: *const ::cmsghdr) -> *mut ::c_uchar {
+        (cmsg as *mut ::c_uchar)
+            .offset(_ALIGN(mem::size_of::<::cmsghdr>()) as isize)
+    }
+
+    pub fn CMSG_LEN(length: ::c_uint) -> ::c_uint {
+        _ALIGN(mem::size_of::<::cmsghdr>()) as ::c_uint + length
+    }
+
+    pub fn CMSG_NXTHDR(mhdr: *const ::msghdr, cmsg: *const ::cmsghdr)
+        -> *mut ::cmsghdr
+    {
+        if cmsg.is_null() {
+            return ::CMSG_FIRSTHDR(mhdr);
+        };
+        let next = cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize)
+            + _ALIGN(mem::size_of::<::cmsghdr>());
+        let max = (*mhdr).msg_control as usize
+            + (*mhdr).msg_controllen as usize;
+        if next > max {
+            0 as *mut ::cmsghdr
+        } else {
+            (cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize))
+                as *mut ::cmsghdr
+        }
+    }
+
+    pub fn CMSG_SPACE(length: ::c_uint) -> ::c_uint {
+        (_ALIGN(mem::size_of::<::cmsghdr>()) + _ALIGN(length as usize))
+            as ::c_uint
+    }
+
     pub fn uname(buf: *mut ::utsname) -> ::c_int {
         __xuname(256, buf as *mut ::c_void)
     }
diff --git a/libc/src/unix/bsd/freebsdlike/freebsd/x86.rs b/libc/src/unix/bsd/freebsdlike/freebsd/x86.rs
index 8a5e5f9..a5495aa 100644
--- a/libc/src/unix/bsd/freebsdlike/freebsd/x86.rs
+++ b/libc/src/unix/bsd/freebsdlike/freebsd/x86.rs
@@ -1,3 +1,5 @@
+use dox::mem;
+
 pub type c_long = i32;
 pub type c_ulong = u32;
 pub type time_t = i32;
@@ -29,3 +31,7 @@ s! {
         __unused: [u8; 8],
     }
 }
+
+// should be pub(crate), but that requires Rust 1.18.0
+#[doc(hidden)]
+pub const _ALIGNBYTES: usize = mem::size_of::<::c_long>() - 1;
diff --git a/libc/src/unix/bsd/freebsdlike/freebsd/x86_64.rs b/libc/src/unix/bsd/freebsdlike/freebsd/x86_64.rs
index 3d61f88..711feb7 100644
--- a/libc/src/unix/bsd/freebsdlike/freebsd/x86_64.rs
+++ b/libc/src/unix/bsd/freebsdlike/freebsd/x86_64.rs
@@ -1,3 +1,5 @@
+use dox::mem;
+
 pub type c_long = i64;
 pub type c_ulong = u64;
 pub type time_t = i64;
@@ -29,4 +31,7 @@ s! {
     }
 }
 
+// should be pub(crate), but that requires Rust 1.18.0
+#[doc(hidden)]
+pub const _ALIGNBYTES: usize = mem::size_of::<::c_long>() - 1;
 pub const MAP_32BIT: ::c_int = 0x00080000;
diff --git a/libc/src/unix/bsd/freebsdlike/mod.rs b/libc/src/unix/bsd/freebsdlike/mod.rs
index 9829dde..22c11b3 100644
--- a/libc/src/unix/bsd/freebsdlike/mod.rs
+++ b/libc/src/unix/bsd/freebsdlike/mod.rs
@@ -82,13 +82,6 @@ s! {
         pub sa_mask: sigset_t,
     }
 
-    pub struct stack_t {
-        // In FreeBSD 11 and later, ss_sp is actually a void*
-        pub ss_sp: *mut ::c_char,
-        pub ss_size: ::size_t,
-        pub ss_flags: ::c_int,
-    }
-
     pub struct sched_param {
         pub sched_priority: ::c_int,
     }