Files
turso/extensions/core/src/lib.rs
2025-02-06 09:15:39 -05:00

124 lines
3.5 KiB
Rust

mod types;
pub use limbo_macros::{register_extension, scalar, AggregateDerive, VTabModuleDerive};
use std::os::raw::{c_char, c_void};
pub use types::{ResultCode, Value, ValueType};
#[repr(C)]
pub struct ExtensionApi {
pub ctx: *mut c_void,
pub register_scalar_function: unsafe extern "C" fn(
ctx: *mut c_void,
name: *const c_char,
func: ScalarFunction,
) -> ResultCode,
pub register_aggregate_function: unsafe extern "C" fn(
ctx: *mut c_void,
name: *const c_char,
args: i32,
init_func: InitAggFunction,
step_func: StepFunction,
finalize_func: FinalizeFunction,
) -> ResultCode,
pub register_module: unsafe extern "C" fn(
ctx: *mut c_void,
name: *const c_char,
module: VTabModuleImpl,
) -> ResultCode,
pub declare_vtab: unsafe extern "C" fn(
ctx: *mut c_void,
name: *const c_char,
sql: *const c_char,
) -> ResultCode,
}
impl ExtensionApi {
pub fn declare_virtual_table(&self, name: &str, sql: &str) -> ResultCode {
let Ok(name) = std::ffi::CString::new(name) else {
return ResultCode::Error;
};
let Ok(sql) = std::ffi::CString::new(sql) else {
return ResultCode::Error;
};
unsafe { (self.declare_vtab)(self.ctx, name.as_ptr(), sql.as_ptr()) }
}
}
pub type ExtensionEntryPoint = unsafe extern "C" fn(api: *const ExtensionApi) -> ResultCode;
pub type ScalarFunction = unsafe extern "C" fn(argc: i32, *const Value) -> Value;
pub type InitAggFunction = unsafe extern "C" fn() -> *mut AggCtx;
pub type StepFunction = unsafe extern "C" fn(ctx: *mut AggCtx, argc: i32, argv: *const Value);
pub type FinalizeFunction = unsafe extern "C" fn(ctx: *mut AggCtx) -> Value;
pub trait Scalar {
fn call(&self, args: &[Value]) -> Value;
}
#[repr(C)]
pub struct AggCtx {
pub state: *mut c_void,
}
pub trait AggFunc {
type State: Default;
const NAME: &'static str;
const ARGS: i32;
fn step(state: &mut Self::State, args: &[Value]);
fn finalize(state: Self::State) -> Value;
}
#[repr(C)]
#[derive(Clone, Debug)]
pub struct VTabModuleImpl {
pub name: *const c_char,
pub connect: VtabFnConnect,
pub open: VtabFnOpen,
pub filter: VtabFnFilter,
pub column: VtabFnColumn,
pub next: VtabFnNext,
pub eof: VtabFnEof,
}
pub type VtabFnConnect = unsafe extern "C" fn(api: *const c_void) -> ResultCode;
pub type VtabFnOpen = unsafe extern "C" fn() -> *mut c_void;
pub type VtabFnFilter =
unsafe extern "C" fn(cursor: *mut c_void, argc: i32, argv: *const Value) -> ResultCode;
pub type VtabFnColumn = unsafe extern "C" fn(cursor: *mut c_void, idx: u32) -> Value;
pub type VtabFnNext = unsafe extern "C" fn(cursor: *mut c_void) -> ResultCode;
pub type VtabFnEof = unsafe extern "C" fn(cursor: *mut c_void) -> bool;
pub trait VTabModule: 'static {
type VCursor: VTabCursor;
const NAME: &'static str;
fn connect(api: &ExtensionApi) -> ResultCode;
fn open() -> Self::VCursor;
fn filter(cursor: &mut Self::VCursor, arg_count: i32, args: &[Value]) -> ResultCode;
fn column(cursor: &Self::VCursor, idx: u32) -> Value;
fn next(cursor: &mut Self::VCursor) -> ResultCode;
fn eof(cursor: &Self::VCursor) -> bool;
}
pub trait VTabCursor: Sized {
type Error: std::fmt::Display;
fn rowid(&self) -> i64;
fn column(&self, idx: u32) -> Value;
fn eof(&self) -> bool;
fn next(&mut self) -> ResultCode;
}
#[repr(C)]
pub struct VTabImpl {
pub module: VTabModuleImpl,
}