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/**
A somewhat reduced test case to expose some Valgrind issues.
This originally came from the word-count benchmark.
*/
use std;
import option = option::t;
import option::some;
import option::none;
import str;
import vec;
import std::map;
import task;
import comm::chan;
import comm::port;
import comm::send;
import comm::recv;
import comm;
fn map(filename: str, emit: map_reduce::putter) { emit(filename, "1"); }
mod map_reduce {
export putter;
export mapper;
export map_reduce;
type putter = fn@(str, str);
type mapper = fn(str, putter);
tag ctrl_proto { find_reducer([u8], chan<int>); mapper_done; }
fn start_mappers(ctrl: chan<ctrl_proto>, inputs: [str]) {
for i: str in inputs { task::spawn((ctrl, i), map_task); }
}
fn map_task(&&args: (chan<ctrl_proto>, str)) {
let (ctrl, input) = args;
let intermediates = map::new_str_hash();
fn emit(im: map::hashmap<str, int>, ctrl: chan<ctrl_proto>, key: str,
val: str) {
let c;
alt im.find(key) {
some(_c) { c = _c }
none. {
let p = port();
log_err "sending find_reducer";
send(ctrl, find_reducer(str::bytes(key), chan(p)));
log_err "receiving";
c = recv(p);
log_err c;
im.insert(key, c);
}
}
}
map(input, bind emit(intermediates, ctrl, _, _));
send(ctrl, mapper_done);
}
fn map_reduce(inputs: [str]) {
let ctrl = port();
// This task becomes the master control task. It spawns others
// to do the rest.
let reducers: map::hashmap<str, int>;
reducers = map::new_str_hash();
start_mappers(chan(ctrl), inputs);
let num_mappers = vec::len(inputs) as int;
while num_mappers > 0 {
alt recv(ctrl) {
mapper_done. { num_mappers -= 1; }
find_reducer(k, cc) {
let c;
alt reducers.find(str::unsafe_from_bytes(k)) {
some(_c) { c = _c; }
none. { c = 0; }
}
send(cc, c);
}
}
}
}
}
fn main() {
map_reduce::map_reduce(["../src/test/run-pass/hashmap-memory.rs"]);
}
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