wrote basic tests for spinlock and fixed a bug in the spinlock class

test/.gitignore

@@ -1,5 +1,6 @@
-# ignore object files
+# ignore object and executable files
 *.o
+tests
 
 # ignore the library, download your own copy via install.sh
 catch.hpp

test/Makefile

@@ -1,7 +1,8 @@
 TARGET = tests
 LIBS = -lm
 CC = c++
-CFLAGS = -g -Wall
+CFLAGS = -g -Wall -std=c++1y
+INCLUDE = "../"
 
 .PHONY: default all clean
 
@@ -12,13 +13,17 @@ OBJECTS = $(patsubst %.cpp, %.o, $(wildcard *.cpp))
 HEADERS = $(wildcard *.hpp)
 
 %.o: %.cpp $(HEADERS)
-    $(CC) $(CFLAGS) -c $< -o $@
+	$(CC) $(CFLAGS) -I $(INCLUDE) -c $< -o $@
 
 .PRECIOUS: $(TARGET) $(OBJECTS)
 
 $(TARGET): $(OBJECTS)
-    $(CC) $(OBJECTS) -Wall $(LIBS) -o $@
+	$(CC) $(OBJECTS) -Wall $(LIBS) -o $@
 
 clean:
-    -rm -f *.o
-    -rm -f $(TARGET)
+	-rm -f *.o
+	-rm -f $(TARGET)
+
+test:
+	make
+	./tests --success

test/spinlock.cpp

@@ -0,0 +1,49 @@
+#include <thread>
+#include <chrono>
+#include <vector>
+
+#include "catch.hpp"
+#include "utils/sync/spinlock.hpp"
+
+#include <iostream>
+
+TEST_CASE("a thread can acquire and release the lock", "[spinlock]")
+{
+    SpinLock lock;
+
+    lock.acquire();
+    // i have a lock
+    lock.release();
+
+    REQUIRE(true);
+}
+
+int x = 0;
+
+SpinLock lock;
+
+void test_lock()
+{
+    using namespace std::literals;
+
+    lock.acquire();
+    x++;
+
+    REQUIRE(x < 2);
+    std::this_thread::sleep_for(1s);
+    
+    x--;
+    lock.release();
+}
+
+TEST_CASE("only one thread at a time can own the lock", "[spinlock]")
+{
+    std::vector<std::thread> threads;
+
+    for(int i = 0; i < 10; ++i)
+        threads.push_back(std::thread(test_lock));
+
+    for(auto& thread : threads){
+        thread.join();
+    }
+}

utils/sync/spinlock.hpp

@@ -19,7 +19,7 @@ public:
     }
 
 private:
-    std::atomic_flag lock;
+    std::atomic_flag lock = ATOMIC_FLAG_INIT;
 };
 
 #endif