Copilot commented on code in PR #18918: URL: https://github.com/apache/datafusion/pull/18918#discussion_r2564757785
########## datafusion/ffi/src/execution/task_ctx.rs: ########## @@ -0,0 +1,281 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License. + +use std::{ffi::c_void, sync::Arc}; + +use abi_stable::{ + pmr::ROption, + std_types::{RHashMap, RString}, + StableAbi, +}; +use datafusion_execution::{config::SessionConfig, runtime_env::RuntimeEnv, TaskContext}; +use datafusion_expr::{ + AggregateUDF, AggregateUDFImpl, ScalarUDF, ScalarUDFImpl, WindowUDF, WindowUDFImpl, +}; + +use crate::{ + session_config::FFI_SessionConfig, udaf::FFI_AggregateUDF, udf::FFI_ScalarUDF, + udwf::FFI_WindowUDF, +}; + +/// A stable struct for sharing [`TaskContext`] across FFI boundaries. +#[repr(C)] +#[derive(Debug, StableAbi)] +#[allow(non_camel_case_types)] +pub struct FFI_TaskContext { + pub session_id: unsafe extern "C" fn(&Self) -> RString, + + pub task_id: unsafe extern "C" fn(&Self) -> ROption<RString>, + + pub session_config: unsafe extern "C" fn(&Self) -> FFI_SessionConfig, + + pub scalar_functions: unsafe extern "C" fn(&Self) -> RHashMap<RString, FFI_ScalarUDF>, + + pub aggregate_functions: + unsafe extern "C" fn(&Self) -> RHashMap<RString, FFI_AggregateUDF>, + + pub window_functions: unsafe extern "C" fn(&Self) -> RHashMap<RString, FFI_WindowUDF>, + + /// Release the memory of the private data when it is no longer being used. + pub release: unsafe extern "C" fn(arg: &mut Self), + + /// Internal data. This is only to be accessed by the provider of the plan. + /// The foreign library should never attempt to access this data. + pub private_data: *mut c_void, + + /// Utility to identify when FFI objects are accessed locally through + /// the foreign interface. See [`crate::get_library_marker_id`] and + /// the crate's `README.md` for more information. + pub library_marker_id: extern "C" fn() -> usize, +} + +struct TaskContextPrivateData { + ctx: Arc<TaskContext>, +} + +impl FFI_TaskContext { + unsafe fn inner(&self) -> &Arc<TaskContext> { + let private_data = self.private_data as *const TaskContextPrivateData; + &(*private_data).ctx + } +} + +unsafe extern "C" fn session_id_fn_wrapper(ctx: &FFI_TaskContext) -> RString { + let ctx = ctx.inner(); + ctx.session_id().into() +} + +unsafe extern "C" fn task_id_fn_wrapper(ctx: &FFI_TaskContext) -> ROption<RString> { + let ctx = ctx.inner(); + ctx.task_id().map(|s| s.as_str().into()).into() +} + +unsafe extern "C" fn session_config_fn_wrapper( + ctx: &FFI_TaskContext, +) -> FFI_SessionConfig { + let ctx = ctx.inner(); + ctx.session_config().into() +} + +unsafe extern "C" fn scalar_functions_fn_wrapper( + ctx: &FFI_TaskContext, +) -> RHashMap<RString, FFI_ScalarUDF> { + let ctx = ctx.inner(); + ctx.scalar_functions() + .iter() + .map(|(name, udf)| (name.to_owned().into(), Arc::clone(udf).into())) + .collect() +} + +unsafe extern "C" fn aggregate_functions_fn_wrapper( + ctx: &FFI_TaskContext, +) -> RHashMap<RString, FFI_AggregateUDF> { + let ctx = ctx.inner(); + ctx.aggregate_functions() + .iter() + .map(|(name, udaf)| { + ( + name.to_owned().into(), + FFI_AggregateUDF::from(Arc::clone(udaf)), + ) + }) + .collect() +} + +unsafe extern "C" fn window_functions_fn_wrapper( + ctx: &FFI_TaskContext, +) -> RHashMap<RString, FFI_WindowUDF> { + let ctx = ctx.inner(); + ctx.window_functions() + .iter() + .map(|(name, udf)| (name.to_owned().into(), FFI_WindowUDF::from(Arc::clone(udf)))) + .collect() +} + +unsafe extern "C" fn release_fn_wrapper(ctx: &mut FFI_TaskContext) { + let private_data = Box::from_raw(ctx.private_data as *mut TaskContextPrivateData); + drop(private_data); +} + +impl Drop for FFI_TaskContext { + fn drop(&mut self) { + unsafe { (self.release)(self) } + } +} + +impl From<Arc<TaskContext>> for FFI_TaskContext { + fn from(ctx: Arc<TaskContext>) -> Self { + let private_data = Box::new(TaskContextPrivateData { ctx }); + + FFI_TaskContext { + session_id: session_id_fn_wrapper, + task_id: task_id_fn_wrapper, + session_config: session_config_fn_wrapper, + scalar_functions: scalar_functions_fn_wrapper, + aggregate_functions: aggregate_functions_fn_wrapper, + window_functions: window_functions_fn_wrapper, + release: release_fn_wrapper, + private_data: Box::into_raw(private_data) as *mut c_void, + library_marker_id: crate::get_library_marker_id, + } + } +} + +impl From<FFI_TaskContext> for Arc<TaskContext> { + fn from(ffi_ctx: FFI_TaskContext) -> Self { + unsafe { + if (ffi_ctx.library_marker_id)() == crate::get_library_marker_id() { + return Arc::clone(ffi_ctx.inner()); + } + + let task_id = (ffi_ctx.task_id)(&ffi_ctx).map(|s| s.to_string()).into(); + let session_id = (ffi_ctx.session_id)(&ffi_ctx).into(); + let session_config = (ffi_ctx.session_config)(&ffi_ctx); + let session_config = + SessionConfig::try_from(&session_config).unwrap_or_default(); + + let scalar_functions = (ffi_ctx.scalar_functions)(&ffi_ctx) + .into_iter() + .filter_map(|kv_pair| { + let udf = <Arc<dyn ScalarUDFImpl>>::try_from(&kv_pair.1); + + if let Err(err) = &udf { + log::error!("Unable to create WindowUDF in FFI: {err}") Review Comment: The error message mentions 'WindowUDF' but this is in the scalar_functions conversion code. Should be 'ScalarUDF' to accurately reflect the function type being created. ```suggestion log::error!("Unable to create ScalarUDF in FFI: {err}") ``` ########## datafusion/ffi/src/session_config.rs: ########## @@ -172,13 +164,15 @@ mod tests { let session_config = SessionConfig::new(); let original_options = session_config.options().entries(); - let ffi_config: FFI_SessionConfig = (&session_config).into(); + let mut ffi_config: FFI_SessionConfig = (&session_config).into(); + let _ = ffi_config.clone(); + ffi_config.library_marker_id = crate::mock_foreign_marker_id; - let foreign_config: ForeignSessionConfig = (&ffi_config).try_into()?; + let foreign_config: SessionConfig = (&ffi_config).try_into()?; - let returned_options = foreign_config.0.options().entries(); + let returned_options = foreign_config.options().entries(); - assert!(original_options.len() == returned_options.len()); + assert_eq!(original_options.len(), returned_options.len()); Review Comment: The test only verifies that the number of config options matches, but doesn't verify that the actual option values round-trip correctly. Consider adding assertions to check that specific config values are preserved. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
