Add bindings to the encryption extension

Cargo.toml

@@ -18,8 +18,11 @@ keywords = ["database"]
 
 [features]
 default = ["linkage"]
-bundled = ["sqlite3-src/bundled"]
+
 linkage = ["sqlite3-src"]
+bundled = ["sqlite3-src/bundled"]
+
+encryption = []
 
 [dependencies.sqlite3-src]
 version = "0.6"

README.md

@@ -2,6 +2,16 @@
 
 The package provides bindings to [SQLite].
 
+The following Cargo features are supported:
+
+* `linkage` creates a dependency on `sqlite3-src`, which links to a suitable
+  SQLite library;
+* `bundled` compiles SQLite from the source code, ignoring any libraries that
+  might be installed in the system; and
+* `encryption` enables bindings to the [SQLite Encryption Extension], which is
+  closed source and hence requires purchasing a license and installing SQLite
+  manually.
+
 ## Development
 
 ```shell
@@ -19,6 +29,7 @@ pull request. Note that any contribution submitted for inclusion in the project
 will be licensed according to the terms given in [LICENSE.md](LICENSE.md).
 
 [SQLite]: https://www.sqlite.org
+[SQLite Encryption Extension]: https://www.sqlite.org/see/doc/release/www/index.wiki
 
 [build-img]: https://github.com/stainless-steel/sqlite3-sys/workflows/build/badge.svg
 [build-url]: https://github.com/stainless-steel/sqlite3-sys/actions/workflows/build.yml

src/encryption.rs

@@ -0,0 +1,20 @@
+use core::ffi::{c_char, c_int, c_void};
+
+use crate::bindings::sqlite3;
+
+extern "C" {
+    pub fn sqlite3_key(db: *mut sqlite3, pKey: *const c_void, nKey: c_int) -> c_int;
+    pub fn sqlite3_key_v2(
+        db: *mut sqlite3,
+        zDbName: *const c_char,
+        pKey: *const c_void,
+        nKey: c_int,
+    ) -> c_int;
+    pub fn sqlite3_rekey(db: *mut sqlite3, pKey: *const c_void, nKey: c_int) -> c_int;
+    pub fn sqlite3_rekey_v2(
+        db: *mut sqlite3,
+        zDbName: *const c_char,
+        pKey: *const c_void,
+        nKey: c_int,
+    ) -> c_int;
+}

src/lib.rs

@@ -1,6 +1,17 @@
-//! Bindings to [SQlite][1].
+//! Bindings to [SQlite].
 //!
-//! [1]: https://www.sqlite.org
+//! The following Cargo features are supported:
+//!
+//! * `linkage` creates a dependency on `sqlite3-src`, which links to a suitable
+//!   SQLite library;
+//! * `bundled` compiles SQLite from the source code, ignoring any libraries that
+//!   might be installed in the system; and
+//! * `encryption` enables bindings to the [SQLite Encryption Extension], which is
+//!   closed source and hence requires purchasing a license and installing SQLite
+//!   manually.
+//!
+//! [SQLite]: https://www.sqlite.org
+//! [SQLite Encryption Extension]: https://www.sqlite.org/see/doc/release/www/index.wiki
 
 #![allow(non_camel_case_types, non_snake_case)]
 #![no_std]
@@ -9,5 +20,9 @@
 extern crate sqlite3_src;
 
 mod bindings;
+#[cfg(feature = "encryption")]
+mod encryption;
 
 pub use bindings::*;
+#[cfg(feature = "encryption")]
+pub use encryption::*;