From 784176815e1ef8ccb731819c47b2a973fbd4c731 Mon Sep 17 00:00:00 2001
From: Maxim Sharabayko <maxsharabayko@haivision.com>
Date: Tue, 9 Jun 2020 09:34:02 +0200
Subject: [PATCH] [test] Added tests for CUnitQueue Covers some issues related
 to Local storage depleted issue #486

---
 test/filelist.maf       |  1 +
 test/test_unitqueue.cpp | 88 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 89 insertions(+)
 create mode 100644 test/test_unitqueue.cpp

diff --git a/test/filelist.maf b/test/filelist.maf
index e70327cd84..48cc4108b2 100644
--- a/test/filelist.maf
+++ b/test/filelist.maf
@@ -13,4 +13,5 @@ test_seqno.cpp
 test_socket_options.cpp
 test_sync.cpp
 test_timer.cpp
+test_unitqueue.cpp
 test_utilities.cpp
diff --git a/test/test_unitqueue.cpp b/test/test_unitqueue.cpp
new file mode 100644
index 0000000000..9bbc326510
--- /dev/null
+++ b/test/test_unitqueue.cpp
@@ -0,0 +1,88 @@
+#include <array>
+#include <vector>
+#include "gtest/gtest.h"
+#include "queue.h"
+
+
+using namespace std;
+
+
+/// Create CUnitQueue with queue size of 4 units.
+/// The size of 4 is chosen on purpose, because 
+/// CUnitQueue::getNextAvailUnit(..) has the following
+/// condition `if (m_iCount * 10 > m_iSize * 9)`. With m_iSize = 4
+/// it will be false up until m_iCount becomes 4.
+/// And there was an issue in getNextAvailUnit(..) in taking
+/// the very last element of the queue (it was skipped).
+TEST(CUnitQueue, Increase)
+{
+    const int buffer_size_pkts = 4;
+    CUnitQueue unit_queue;
+    unit_queue.init(buffer_size_pkts, 1500, AF_INET);
+
+    vector<CUnit*> taken_units;
+    for (int i = 0; i < 5 * buffer_size_pkts; ++i)
+    {
+        CUnit* unit = unit_queue.getNextAvailUnit("");
+        ASSERT_NE(unit, nullptr);
+        unit_queue.makeUnitGood(unit, "");
+        taken_units.push_back(unit);
+    }
+}
+
+/// Create CUnitQueue with queue size of 4 units.
+/// Then after requesting the 5th unit, free the previous
+/// four units. This makes the previous queue completely free.
+/// Requesting the 5th unit, there would be 3 units available in the
+/// beginning of the same queue.
+TEST(CUnitQueue, IncreaseAndFree)
+{
+    const int buffer_size_pkts = 4;
+    CUnitQueue unit_queue;
+    unit_queue.init(buffer_size_pkts, 1500, AF_INET);
+
+    CUnit* taken_unit = nullptr;
+    for (int i = 0; i < 5 * buffer_size_pkts; ++i)
+    {
+        CUnit* unit = unit_queue.getNextAvailUnit();
+        ASSERT_NE(unit, nullptr);
+        unit_queue.makeUnitGood(unit);
+
+        if (taken_unit)
+            unit_queue.makeUnitFree(taken_unit);
+
+        taken_unit = unit;
+    }
+}
+
+/// Create CUnitQueue with queue size of 4 units.
+/// Then after requesting the 5th unit, free the previous
+/// four units. This makes the previous queue completely free.
+/// Requesting the 9th unit, there would be 4 units available in the
+/// Thus the test checks if 
+TEST(CUnitQueue, IncreaseAndFreeGrouped)
+{
+    const int buffer_size_pkts = 4;
+    CUnitQueue unit_queue;
+    unit_queue.init(buffer_size_pkts, 1500, AF_INET);
+
+    vector<CUnit*> taken_units;
+    for (int i = 0; i < 5 * buffer_size_pkts; ++i)
+    {
+        CUnit* unit = unit_queue.getNextAvailUnit("");
+        ASSERT_NE(unit, nullptr);
+        unit_queue.makeUnitGood(unit, "");
+
+        if (taken_units.size() >= buffer_size_pkts)
+        {
+            for_each(taken_units.begin(), taken_units.end(),
+                [&unit_queue](CUnit* u) { unit_queue.makeUnitFree(u, ""); });
+
+            taken_units.clear();
+        }
+
+        taken_units.push_back(unit);
+        EXPECT_LE(unit_queue.capacity(), 2 * buffer_size_pkts)
+            << "Buffer capacity should not exceed two queues of 4 units";
+    }
+}