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// run-pass
#![allow(non_camel_case_types)]
#![allow(dead_code)]
#![allow(unused_mut)]
// ignore-emscripten No support for threads
/**
A somewhat reduced test case to expose some Valgrind issues.
This originally came from the word-count benchmark.
*/
pub fn map(filename: String, mut emit: map_reduce::putter) {
emit(filename, "1".to_string());
}
mod map_reduce {
use std::collections::HashMap;
use std::sync::mpsc::{channel, Sender};
use std::str;
use std::thread;
pub type putter<'a> = Box<dyn FnMut(String, String) + 'a>;
pub type mapper = extern "C" fn(String, putter);
enum ctrl_proto { find_reducer(Vec<u8>, Sender<isize>), mapper_done, }
fn start_mappers(ctrl: Sender<ctrl_proto>, inputs: Vec<String>) {
for i in &inputs {
let ctrl = ctrl.clone();
let i = i.clone();
thread::spawn(move|| map_task(ctrl.clone(), i.clone()) );
}
}
fn map_task(ctrl: Sender<ctrl_proto>, input: String) {
let mut intermediates = HashMap::new();
fn emit(im: &mut HashMap<String, isize>,
ctrl: Sender<ctrl_proto>, key: String,
_val: String) {
if im.contains_key(&key) {
return;
}
let (tx, rx) = channel();
println!("sending find_reducer");
ctrl.send(ctrl_proto::find_reducer(key.as_bytes().to_vec(), tx)).unwrap();
println!("receiving");
let c = rx.recv().unwrap();
println!("{}", c);
im.insert(key, c);
}
let ctrl_clone = ctrl.clone();
::map(input, Box::new(|a,b| emit(&mut intermediates, ctrl.clone(), a, b)));
ctrl_clone.send(ctrl_proto::mapper_done).unwrap();
}
pub fn map_reduce(inputs: Vec<String>) {
let (tx, rx) = channel();
// This thread becomes the master control thread. It spawns others
// to do the rest.
let mut reducers: HashMap<String, isize>;
reducers = HashMap::new();
start_mappers(tx, inputs.clone());
let mut num_mappers = inputs.len() as isize;
while num_mappers > 0 {
match rx.recv().unwrap() {
ctrl_proto::mapper_done => { num_mappers -= 1; }
ctrl_proto::find_reducer(k, cc) => {
let mut c;
match reducers.get(&str::from_utf8(&k).unwrap().to_string()) {
Some(&_c) => { c = _c; }
None => { c = 0; }
}
cc.send(c).unwrap();
}
}
}
}
}
pub fn main() {
map_reduce::map_reduce(
vec!["../tests/run-pass/hashmap-memory.rs".to_string()]);
}
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