lock: Add unit tests for namespace lock (#1922)

Fixes #1821

namespace-lock_test.go

@@ -0,0 +1,126 @@
+/*
+ * Minio Cloud Storage, (C) 2016 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import "testing"
+
+// Tests functionality provided by namespace lock.
+func TestNamespaceLockTest(t *testing.T) {
+	// Initialize name space lock.
+	initNSLock()
+
+	// List of test cases.
+	testCases := []struct {
+		lk               func(s1, s2 string)
+		unlk             func(s1, s2 string)
+		rlk              func(s1, s2 string)
+		runlk            func(s1, s2 string)
+		lkCount          int
+		lockedRefCount   uint
+		unlockedRefCount uint
+		shouldPass       bool
+	}{
+		{
+			lk:               nsMutex.Lock,
+			unlk:             nsMutex.Unlock,
+			lockedRefCount:   1,
+			unlockedRefCount: 0,
+			shouldPass:       true,
+		},
+		{
+			rlk:              nsMutex.RLock,
+			runlk:            nsMutex.RUnlock,
+			lockedRefCount:   4,
+			unlockedRefCount: 2,
+			shouldPass:       true,
+		},
+		{
+			rlk:              nsMutex.RLock,
+			runlk:            nsMutex.RUnlock,
+			lockedRefCount:   1,
+			unlockedRefCount: 0,
+			shouldPass:       true,
+		},
+	}
+
+	// Run all test cases.
+
+	// Write lock tests.
+	testCase := testCases[0]
+	testCase.lk("a", "b") // lock once.
+	nsLk, ok := nsMutex.lockMap[nsParam{"a", "b"}]
+	if !ok && testCase.shouldPass {
+		t.Errorf("Lock in map missing.")
+	}
+	// Validate loced ref count.
+	if testCase.lockedRefCount != nsLk.ref && testCase.shouldPass {
+		t.Errorf("Test %d fails, expected to pass. Wanted ref count is %d, got %d", 1, testCase.lockedRefCount, nsLk.ref)
+	}
+	testCase.unlk("a", "b") // unlock once.
+	if testCase.unlockedRefCount != nsLk.ref && testCase.shouldPass {
+		t.Errorf("Test %d fails, expected to pass. Wanted ref count is %d, got %d", 1, testCase.unlockedRefCount, nsLk.ref)
+	}
+	_, ok = nsMutex.lockMap[nsParam{"a", "b"}]
+	if ok && !testCase.shouldPass {
+		t.Errorf("Lock map found after unlock.")
+	}
+
+	// Read lock tests.
+	testCase = testCases[1]
+	testCase.rlk("a", "b") // lock once.
+	testCase.rlk("a", "b") // lock second time.
+	testCase.rlk("a", "b") // lock third time.
+	testCase.rlk("a", "b") // lock fourth time.
+	nsLk, ok = nsMutex.lockMap[nsParam{"a", "b"}]
+	if !ok && testCase.shouldPass {
+		t.Errorf("Lock in map missing.")
+	}
+	// Validate loced ref count.
+	if testCase.lockedRefCount != nsLk.ref && testCase.shouldPass {
+		t.Errorf("Test %d fails, expected to pass. Wanted ref count is %d, got %d", 1, testCase.lockedRefCount, nsLk.ref)
+	}
+	testCase.runlk("a", "b") // unlock once.
+	testCase.runlk("a", "b") // unlock second time.
+	if testCase.unlockedRefCount != nsLk.ref && testCase.shouldPass {
+		t.Errorf("Test %d fails, expected to pass. Wanted ref count is %d, got %d", 2, testCase.unlockedRefCount, nsLk.ref)
+	}
+	_, ok = nsMutex.lockMap[nsParam{"a", "b"}]
+	if !ok && testCase.shouldPass {
+		t.Errorf("Lock map not found.")
+	}
+
+	// Read lock 0 ref count.
+	testCase = testCases[2]
+	testCase.rlk("a", "c") // lock once.
+
+	nsLk, ok = nsMutex.lockMap[nsParam{"a", "c"}]
+	if !ok && testCase.shouldPass {
+		t.Errorf("Lock in map missing.")
+	}
+	// Validate loced ref count.
+	if testCase.lockedRefCount != nsLk.ref && testCase.shouldPass {
+		t.Errorf("Test %d fails, expected to pass. Wanted ref count is %d, got %d", 3, testCase.lockedRefCount, nsLk.ref)
+	}
+	testCase.runlk("a", "c") // unlock once.
+	if testCase.unlockedRefCount != nsLk.ref && testCase.shouldPass {
+		t.Errorf("Test %d fails, expected to pass. Wanted ref count is %d, got %d", 3, testCase.unlockedRefCount, nsLk.ref)
+	}
+	_, ok = nsMutex.lockMap[nsParam{"a", "c"}]
+	if ok && !testCase.shouldPass {
+		t.Errorf("Lock map not found.")
+	}
+}