mirror of
https://github.com/isar/rusqlite.git
synced 2024-11-25 02:21:37 +08:00
f9d69410ef
`to_sqlite_error` needs `sqlite3_malloc` ``` sqlite> .log on sqlite> .load target/debug/examples/libloadable_extension.so Error: error during initialization: SQLite version mismatch: 3014000 < 3042000 ```
51 lines
1.6 KiB
Rust
51 lines
1.6 KiB
Rust
//! Adaptation of https://sqlite.org/loadext.html#programming_loadable_extensions
|
|
use std::os::raw::{c_char, c_int};
|
|
|
|
use rusqlite::ffi;
|
|
use rusqlite::functions::FunctionFlags;
|
|
use rusqlite::types::{ToSqlOutput, Value};
|
|
use rusqlite::{to_sqlite_error, Connection, Result};
|
|
|
|
/// # build
|
|
/// ```sh
|
|
/// cargo build --example loadable_extension --features "loadable_extension modern_sqlite functions vtab trace"
|
|
/// ```
|
|
/// # test
|
|
/// ```sh
|
|
/// sqlite> .log on
|
|
/// sqlite> .load target/debug/examples/libloadable_extension.so
|
|
/// (28) Rusqlite extension initialized
|
|
/// sqlite> SELECT rusqlite_test_function();
|
|
/// Rusqlite extension loaded correctly!
|
|
/// ```
|
|
#[allow(clippy::not_unsafe_ptr_arg_deref)]
|
|
#[no_mangle]
|
|
pub extern "C" fn sqlite3_extension_init(
|
|
db: *mut ffi::sqlite3,
|
|
pz_err_msg: *mut *mut c_char,
|
|
p_api: *mut ffi::sqlite3_api_routines,
|
|
) -> c_int {
|
|
if p_api.is_null() {
|
|
return ffi::SQLITE_ERROR;
|
|
} else if let Err(err) = extension_init(db, p_api) {
|
|
return unsafe { to_sqlite_error(&err, pz_err_msg) };
|
|
}
|
|
ffi::SQLITE_OK
|
|
}
|
|
|
|
fn extension_init(db: *mut ffi::sqlite3, p_api: *mut ffi::sqlite3_api_routines) -> Result<()> {
|
|
let db = unsafe { Connection::extension_init2(db, p_api)? };
|
|
db.create_scalar_function(
|
|
"rusqlite_test_function",
|
|
0,
|
|
FunctionFlags::SQLITE_DETERMINISTIC,
|
|
|_ctx| {
|
|
Ok(ToSqlOutput::Owned(Value::Text(
|
|
"Rusqlite extension loaded correctly!".to_string(),
|
|
)))
|
|
},
|
|
)?;
|
|
rusqlite::trace::log(ffi::SQLITE_WARNING, "Rusqlite extension initialized");
|
|
Ok(())
|
|
}
|