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// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#include "exceptions.h"
#include <cassert>
namespace vespalib {
template <typename IN, typename OUT, bool external_id>
void
Rendezvous<IN, OUT, external_id>::meet_self(IN &input, OUT &output) {
_in[0] = &input;
_out[0] = &output;
mingle();
}
template <typename IN, typename OUT, bool external_id>
void
Rendezvous<IN, OUT, external_id>::meet_others(IN &input, OUT &output, size_t my_id, std::unique_lock<std::mutex> guard)
{
if (external_id) {
assert(_in[my_id] == nullptr);
assert(_out[my_id] == nullptr);
}
_in[my_id] = &input;
_out[my_id] = &output;
if (++_next == _size) {
mingle();
if (external_id) {
std::fill(_in.begin(), _in.end(), nullptr);
std::fill(_out.begin(), _out.end(), nullptr);
}
_next = 0;
++_gen;
_cond.notify_all();
} else {
size_t oldgen = _gen;
while (oldgen == _gen) {
_cond.wait(guard);
}
}
}
template <typename IN, typename OUT, bool external_id>
Rendezvous<IN, OUT, external_id>::Rendezvous(size_t n)
: _lock(),
_cond(),
_size(n),
_next(0),
_gen(0),
_in(n, nullptr),
_out(n, nullptr)
{
if (n == 0) {
throw IllegalArgumentException("size must be greater than 0");
}
}
template <typename IN, typename OUT, bool external_id>
Rendezvous<IN, OUT, external_id>::~Rendezvous() = default;
template <typename IN, typename OUT, bool external_id>
OUT
Rendezvous<IN, OUT, external_id>::rendezvous(IN input)
requires (!external_id)
{
OUT ret{};
static_assert(!external_id);
if (_size == 1) {
meet_self(input, ret);
} else {
std::unique_lock guard(_lock);
meet_others(input, ret, _next, std::move(guard));
}
return ret;
}
template <typename IN, typename OUT, bool external_id>
OUT
Rendezvous<IN, OUT, external_id>::rendezvous(IN input, size_t my_id)
requires (external_id)
{
OUT ret{};
assert(my_id < _size);
static_assert(external_id);
if (_size == 1) {
meet_self(input, ret);
} else {
meet_others(input, ret, my_id, std::unique_lock(_lock));
}
return ret;
}
} // namespace vespalib
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