Support random file of AIX (#282)

Author: ecnelises

src/lib.rs

@@ -34,6 +34,7 @@
 //! | SOLID             | `*-kmc-solid_*`    | `SOLID_RNG_SampleRandomBytes`
 //! | Nintendo 3DS      | `armv6k-nintendo-3ds` | [`getrandom`][1]
 //! | QNX Neutrino      | `*‑nto-qnx*`          | [`/dev/urandom`][14] (identical to `/dev/random`)
+//! | AIX               | `*-ibm-aix`        | [`/dev/urandom`][15]
 //!
 //! There is no blanket implementation on `unix` targets that reads from
 //! `/dev/urandom`. This ensures all supported targets are using the recommended
@@ -162,6 +163,7 @@
 //! [12]: https://docs.oracle.com/cd/E86824_01/html/E54777/random-7d.html
 //! [13]: https://github.com/emscripten-core/emscripten/pull/12240
 //! [14]: https://www.qnx.com/developers/docs/7.1/index.html#com.qnx.doc.neutrino.utilities/topic/r/random.html
+//! [15]: https://www.ibm.com/docs/en/aix/7.3?topic=files-random-urandom-devices
 //!
 //! [`BCryptGenRandom`]: https://docs.microsoft.com/en-us/windows/win32/api/bcrypt/nf-bcrypt-bcryptgenrandom
 //! [`Crypto.getRandomValues`]: https://www.w3.org/TR/WebCryptoAPI/#Crypto-method-getRandomValues
@@ -211,7 +213,7 @@ pub use crate::error::Error;
 // The function MUST NOT ever write uninitialized bytes into `dest`,
 // regardless of what value it returns.
 cfg_if! {
-    if #[cfg(any(target_os = "haiku", target_os = "redox", target_os = "nto"))] {
+    if #[cfg(any(target_os = "haiku", target_os = "redox", target_os = "nto", target_os = "aix"))] {
         mod util_libc;
         #[path = "use_file.rs"] mod imp;
     } else if #[cfg(any(target_os = "android", target_os = "linux"))] {

src/use_file.rs

@@ -25,6 +25,7 @@ use core::{
 #[cfg(any(target_os = "solaris", target_os = "illumos"))]
 const FILE_PATH: &str = "/dev/random\0";
 #[cfg(any(
+    target_os = "aix",
     target_os = "android",
     target_os = "linux",
     target_os = "redox",

src/util_libc.rs

@@ -34,6 +34,8 @@ cfg_if! {
             fn __errno() -> *mut libc::c_int;
         }
         use __errno as errno_location;
+    } else if #[cfg(target_os = "aix")] {
+        use libc::_Errno as errno_location;
     }
 }