Copy example to module level

openssl/src/symm.rs

@@ -1,4 +1,27 @@
 //! High level interface to certain symmetric ciphers.
+//!
+//! # Examples
+//!
+//! Encrypt data in AES128 CBC mode
+//!
+//! ```
+//! use openssl::symm::{encrypt, Cipher};
+//!
+//! let cipher = Cipher::aes_128_cbc();
+//! let data = b"Some Crypto Text";
+//! let key = b"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F";
+//! let iv = b"\x00\x01\x02\x03\x04\x05\x06\x07\x00\x01\x02\x03\x04\x05\x06\x07";
+//! let ciphertext = encrypt(
+//!     cipher,
+//!     key,
+//!     Some(iv),
+//!     data).unwrap();
+//!
+//! assert_eq!(
+//!     b"\xB4\xB9\xE7\x30\xD6\xD6\xF7\xDE\x77\x3F\x1C\xFF\xB3\x3E\x44\x5A\x91\xD7\x27\x62\x87\x4D\
+//!       \xFB\x3C\x5E\xC4\x59\x72\x4A\xF4\x7C\xA1",
+//!     &ciphertext[..]);
+//! ```
 use std::cmp;
 use std::ptr;
 use libc::c_int;