Use getrandom_syscall in getrandom_available

Author: newpavlov

src/linux_android_with_fallback.rs

@@ -17,8 +17,7 @@ pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> {
 }
 
 fn is_getrandom_available() -> bool {
-    let res = unsafe { getrandom(core::ptr::null_mut(), 0, libc::GRND_NONBLOCK) };
-    if res < 0 {
+    if getrandom_syscall(&[]) < 0 {
         match last_os_error().raw_os_error() {
             Some(libc::ENOSYS) => false, // No kernel support
             Some(libc::EPERM) => false,  // Blocked by seccomp
@@ -28,11 +27,3 @@ fn is_getrandom_available() -> bool {
         true
     }
 }
-
-unsafe fn getrandom(
-    buf: *mut libc::c_void,
-    buflen: libc::size_t,
-    flags: libc::c_uint,
-) -> libc::ssize_t {
-    libc::syscall(libc::SYS_getrandom, buf, buflen, flags) as libc::ssize_t
-}