rumtk_core/queue.rs
1/*
2 * rumtk attempts to implement HL7 and medical protocols for interoperability in medicine.
3 * This toolkit aims to be reliable, simple, performant, and standards compliant.
4 * Copyright (C) 2025 Luis M. Santos, M.D.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20pub mod queue {
21 use crate::core::RUMResult;
22 use crate::threading::thread_primitives::*;
23 use crate::{rumtk_init_threads, rumtk_resolve_task, rumtk_spawn_task, threading};
24 use std::future::Future;
25 use std::thread::sleep;
26 use std::time::Duration;
27
28 pub const DEFAULT_SLEEP_DURATION: Duration = Duration::from_millis(1);
29 pub const DEFAULT_QUEUE_CAPACITY: usize = 10;
30 pub const DEFAULT_MICROTASK_QUEUE_CAPACITY: usize = 5;
31
32 pub struct TaskQueue<R> {
33 tasks: AsyncTaskHandles<R>,
34 runtime: &'static SafeTokioRuntime,
35 }
36
37 impl<R> TaskQueue<R>
38 where
39 R: Sync + Send + Clone + 'static,
40 {
41 ///
42 /// This method creates a [`TaskQueue`] instance using sensible defaults.
43 ///
44 /// The `threads` field is computed from the number of cores present in system.
45 ///
46 pub fn default() -> RUMResult<TaskQueue<R>> {
47 Self::new(&threading::threading_functions::get_default_system_thread_count())
48 }
49
50 ///
51 /// Creates an instance of [`ThreadedTaskQueue<T, R>`] in the form of [`SafeThreadedTaskQueue<T, R>`].
52 /// Expects you to provide the count of threads to spawn and the microtask queue size
53 /// allocated by each thread.
54 ///
55 /// This method calls [`Self::with_capacity()`] for the actual object creation.
56 /// The main queue capacity is pre-allocated to [`DEFAULT_QUEUE_CAPACITY`].
57 ///
58 pub fn new(worker_num: &usize) -> RUMResult<TaskQueue<R>> {
59 let tasks = AsyncTaskHandles::with_capacity(DEFAULT_QUEUE_CAPACITY);
60 let runtime = rumtk_init_threads!(&worker_num);
61 Ok(TaskQueue { tasks, runtime })
62 }
63
64 ///
65 /// Add a task to the processing queue. The idea is that you can queue a processor function
66 /// and list of args that will be picked up by one of the threads for processing.
67 ///
68 pub fn add_task<F>(&mut self, task: F)
69 where
70 F: Future<Output = TaskResult<R>> + Send + Sync + 'static,
71 F::Output: Send + 'static,
72 {
73 let handle = rumtk_spawn_task!(&self.runtime, task);
74 self.tasks.push(handle);
75 }
76
77 ///
78 /// This method waits until all queued tasks have been processed from the main queue.
79 ///
80 /// We poll the status of the main queue every [`DEFAULT_SLEEP_DURATION`] ms.
81 ///
82 /// Upon completion,
83 ///
84 /// 1. We collect the results generated (if any).
85 /// 2. We reset the main task and result internal queue states.
86 /// 3. Return the list of results ([`TaskResults<R>`]).
87 ///
88 /// ### Note:
89 /// ```text
90 /// Results returned here are not guaranteed to be in the same order as the order in which
91 /// the tasks were queued for work. You will need to pass a type as T that automatically
92 /// tracks its own id or has a way for you to resort results.
93 /// ```
94 pub fn wait(&mut self) -> TaskResults<R> {
95 while !self.is_completed() {
96 sleep(DEFAULT_SLEEP_DURATION);
97 }
98
99 let results = self.gather();
100 self.reset();
101 results
102 }
103
104 ///
105 /// Check if all work has been completed from the task queue.
106 ///
107 /// This implementation is branchless.
108 ///
109 pub fn is_completed(&self) -> bool {
110 let mut accumulator: usize = 0;
111
112 if self.tasks.is_empty() {
113 return false;
114 }
115
116 for task in self.tasks.iter() {
117 accumulator += task.is_finished() as usize;
118 }
119 (accumulator / self.tasks.len()) > 0
120 }
121
122 ///
123 /// Reset task queue and results queue states.
124 ///
125 pub fn reset(&mut self) {
126 self.tasks.clear();
127 }
128
129 fn gather(&mut self) -> TaskResults<R> {
130 let mut result_queue = TaskResults::<R>::with_capacity(self.tasks.len());
131 for i in 0..self.tasks.len() {
132 let task = self.tasks.pop().unwrap();
133 result_queue.push(rumtk_resolve_task!(&self.runtime, task).unwrap());
134 }
135 result_queue
136 }
137 }
138}
139
140pub mod queue_macros {
141 #[macro_export]
142 macro_rules! rumtk_new_task_queue {
143 ( $worker_num:expr ) => {{
144 use $crate::queue::queue::TaskQueue;
145 TaskQueue::new($worker_num);
146 }};
147 }
148}