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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;
import option::some;
import option::none;
import str;
import vec;
import std::map;
import std::map::hashmap;
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 = extern fn(str, putter);
enum ctrl_proto { find_reducer(~[u8], chan<int>), mapper_done, }
fn start_mappers(ctrl: chan<ctrl_proto>, inputs: ~[str]) {
for inputs.each |i| {
task::spawn(|| map_task(ctrl, i) );
}
}
fn map_task(ctrl: chan<ctrl_proto>, input: str) {
let intermediates = map::str_hash();
fn emit(im: map::hashmap<str, int>, ctrl: chan<ctrl_proto>, key: str,
val: str) {
let mut c;
alt im.find(key) {
some(_c) { c = _c }
none {
let p = port();
#error("sending find_reducer");
send(ctrl, find_reducer(str::bytes(key), chan(p)));
#error("receiving");
c = recv(p);
log(error, c);
im.insert(key, c);
}
}
}
map(input, |a,b| emit(intermediates, ctrl, a, b) );
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 mut reducers: map::hashmap<str, int>;
reducers = map::str_hash();
start_mappers(chan(ctrl), inputs);
let mut num_mappers = vec::len(inputs) as int;
while num_mappers > 0 {
alt recv(ctrl) {
mapper_done { num_mappers -= 1; }
find_reducer(k, cc) {
let mut c;
alt reducers.find(str::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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