Auto merge of #3443 - devnexen:apple_getentropy, r=JohnTitor

adding getentropy for apple devices.

Author: bors

libc-test/build.rs

@@ -268,6 +268,7 @@ fn test_apple(target: &str) {
         "sys/proc_info.h",
         "sys/ptrace.h",
         "sys/quota.h",
+        "sys/random.h",
         "sys/resource.h",
         "sys/sem.h",
         "sys/shm.h",

libc-test/semver/apple.txt

@@ -1915,6 +1915,7 @@ getattrlistbulk
 getdate
 getdomainname
 getdtablesize
+getentropy
 getfsstat
 getgrent
 getgrgid

src/unix/bsd/apple/mod.rs

@@ -6260,6 +6260,7 @@ extern "C" {
     pub fn sethostid(hostid: ::c_long);
 
     pub fn CCRandomGenerateBytes(bytes: *mut ::c_void, size: ::size_t) -> ::CCRNGStatus;
+    pub fn getentropy(buf: *mut ::c_void, buflen: ::size_t) -> ::c_int;
 
     pub fn _NSGetExecutablePath(buf: *mut ::c_char, bufsize: *mut u32) -> ::c_int;
     pub fn _NSGetEnviron() -> *mut *mut *mut ::c_char;