freebsd kcmp call support.

(backport <rust-lang#3746>)
(cherry picked from commit 68ebe1d)

Author: devnexen

libc-test/build.rs

@@ -2510,6 +2510,13 @@ fn test_freebsd(target: &str) {
                 true
             }
 
+            // Added in FreeBSD 14.1
+            "KCMP_FILE" | "KCMP_FILEOBJ" | "KCMP_FILES" | "KCMP_SIGHAND" | "KCMP_VM"
+                if Some(14) > freebsd_ver =>
+            {
+                true
+            }
+
             // FIXME: Removed in FreeBSD 15:
             "LOCAL_CONNWAIT" if freebsd_ver >= Some(15) => true,
 
@@ -2626,6 +2633,9 @@ fn test_freebsd(target: &str) {
                 true
             }
 
+            // Those are introduced in FreeBSD 14.1.
+            "kcmp" => true,
+
             _ => false,
         }
     });

libc-test/semver/freebsd.txt

@@ -687,6 +687,11 @@ JAIL_SYS_DISABLE
 JAIL_SYS_INHERIT
 JAIL_SYS_NEW
 JAIL_UPDATE
+KCMP_FILE
+KCMP_FILEOBJ
+KCMP_FILES
+KCMP_SIGHAND
+KCMP_VM
 KENV_GET
 KENV_SET
 KENV_UNSET
@@ -1974,6 +1979,7 @@ jail_get
 jail_remove
 jail_set
 jrand48
+kcmp
 kevent
 key_t
 killpg

src/unix/bsd/freebsdlike/freebsd/mod.rs

@@ -4923,6 +4923,12 @@ pub const TFD_CLOEXEC: ::c_int = O_CLOEXEC;
 pub const TFD_TIMER_ABSTIME: ::c_int = 0x01;
 pub const TFD_TIMER_CANCEL_ON_SET: ::c_int = 0x02;
 
+pub const KCMP_FILE: ::c_int = 100;
+pub const KCMP_FILEOBJ: ::c_int = 101;
+pub const KCMP_FILES: ::c_int = 102;
+pub const KCMP_SIGHAND: ::c_int = 103;
+pub const KCMP_VM: ::c_int = 104;
+
 cfg_if! {
     if #[cfg(libc_const_extern_fn)] {
         pub const fn MAP_ALIGNED(a: ::c_int) -> ::c_int {
@@ -5648,6 +5654,14 @@ extern "C" {
     ) -> ::c_int;
     pub fn closefrom(lowfd: ::c_int);
     pub fn close_range(lowfd: ::c_uint, highfd: ::c_uint, flags: ::c_int) -> ::c_int;
+
+    pub fn kcmp(
+        pid1: ::pid_t,
+        pid2: ::pid_t,
+        type_: ::c_int,
+        idx1: ::c_ulong,
+        idx2: ::c_ulong,
+    ) -> ::c_int;
 }
 
 #[link(name = "memstat")]