Proposal for fixing the issue skypjack#292

Signed-off-by: Fiorentino, Stefano <[email protected]>

src/uvw/thread.cpp

@@ -9,7 +9,8 @@ namespace uvw {
 UVW_INLINE thread::thread(loop::token token, std::shared_ptr<loop> ref, task t, std::shared_ptr<void> d) noexcept
     : uv_type{token, std::move(ref)},
       data{std::move(d)},
-      func{std::move(t)} {}
+      func{std::move(t)},
+      joined{false} {}
 
 UVW_INLINE void thread::create_callback(void *arg) {
     thread &curr = *(static_cast<thread *>(arg));
@@ -42,7 +43,10 @@ UVW_INLINE bool thread::run(create_flags opts, std::size_t stack) noexcept {
 }
 
 UVW_INLINE bool thread::join() noexcept {
-    return (0 == uv_thread_join(raw()));
+    if(!joined && 0 == uv_thread_join(raw())) {
+        joined = true;
+    }
+    return joined;
 }
 
 UVW_INLINE thread_local_storage::thread_local_storage(loop::token token, std::shared_ptr<loop> ref) noexcept

src/uvw/thread.h

@@ -106,6 +106,7 @@ class thread final: public uv_type<uv_thread_t> {
 private:
     std::shared_ptr<void> data;
     task func;
+    bool joined;
 };
 
 /**

test/uvw/thread.cpp

@@ -72,3 +72,31 @@ TEST(Mutex, RecursiveLockUnlock) {
 
     loop->run();
 }
+
+TEST(Thread, joined)
+{
+    auto loop = uvw::loop::get_default();
+    auto threadWorker = [](std::shared_ptr<void> d) {
+        std::cout << "all done" << std::endl;
+    };
+
+    std::vector<std::shared_ptr<uvw::thread>> threads;
+    for (int i = 0; i < 8; i++)
+    {
+        auto threadId = std::make_shared<int>(i);
+        auto threadHandle = loop->resource<uvw::thread>(threadWorker, threadId);
+        threads.push_back(threadHandle);
+    }
+
+    for (auto& threadHandle : threads) 
+    {
+        threadHandle->run();
+    }
+
+    loop->run();
+
+    for (auto& threadHandle : threads) 
+    {
+        threadHandle->join();
+    }
+}