Add a "TimeSource" class

.circleci/config/jobs/test_esp32_qemu.yml

@@ -6,3 +6,9 @@ steps:
     - run:
           name: Build ESP32 QEMU and Run Tests
           command: scripts/tests/esp32_qemu_tests.sh
+    - run:
+          name: Save test log files
+          command: scripts/tests/save_logs.sh /tmp/test_logs
+          when: on_fail
+    - store_artifacts:
+          path: /tmp/test_logs

src/system/SystemLayer.am

@@ -50,4 +50,5 @@ CHIP_BUILD_SYSTEM_LAYER_HEADER_FILES                  = \
     @top_builddir@/src/system/SystemObject.h            \
     @top_builddir@/src/system/SystemTimer.h             \
     @top_builddir@/src/system/SystemPacketBuffer.h      \
+    @top_builddir@/src/system/TimeSource.h              \
     $(NULL)

src/system/TimeSource.h

@@ -0,0 +1,90 @@
+/*
+ *
+ *    Copyright (c) 2020 Project CHIP Authors
+ *
+ *    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.
+ */
+
+/**
+ * @brief defines a generic time source interface that uses a real clock
+ *        at runtime but can be substituted by a test one for unit tests.
+ */
+#ifndef TIME_SOURCE_H_
+#define TIME_SOURCE_H_
+
+#include <system/SystemClock.h>
+
+namespace chip {
+namespace Time {
+
+enum class Source
+{
+    kSystem, // System time source
+    kTest,   // Test time source
+};
+
+/**
+ * Defines a generic time source within a system. System time and test times
+ * are available.
+ */
+template <Source kSource>
+class TimeSource
+{
+public:
+    /**
+     * Returns a monotonically increasing time in milliseconds since an arbitrary, platform-defined
+     * epoch.
+     *
+     * Maintains requirements for the System::Platform::Layer clock implementation:
+     *
+     *  - Return a value that is ever-increasing (i.e. never * wraps) between reboots of the system.
+     *  - The underlying time source is required to tick continuously during any system sleep modes
+     *    such that the values do not entail a restart upon wake.
+     *  - This function is expected to be thread-safe on any platform that employs threading.
+     */
+    uint64_t GetCurrentMonotonicTimeMs();
+};
+
+/**
+ * A system time source, based on the system platform layer.
+ */
+template <>
+class TimeSource<Source::kSystem>
+{
+public:
+    uint64_t GetCurrentMonotonicTimeMs() { return System::Platform::Layer::GetClock_MonotonicMS(); }
+};
+
+/**
+ * A test time source. Allows setting the current time.
+ */
+template <>
+class TimeSource<Source::kTest>
+{
+public:
+    uint64_t GetCurrentMonotonicTimeMs() { return mCurrentTimeMs; }
+
+    void SetCurrentMonotonicTimeMs(uint64_t value)
+    {
+        VerifyOrDie(value >= mCurrentTimeMs); // required contract
+        mCurrentTimeMs = value;
+    }
+
+private:
+    uint64_t mCurrentTimeMs = 0;
+};
+
+} // namespace Time
+} // namespace chip
+
+#endif // TIME_SOURCE_H_

src/system/tests/Makefile.am

@@ -47,6 +47,7 @@ libSystemLayerTests_a_SOURCES                         = \
     TestSystemObject.cpp                                \
     TestSystemPacketBuffer.cpp                          \
     TestSystemTimer.cpp                                 \
+    TestTimeSource.cpp                                  \
     $(NULL)
 
 libSystemLayerTests_adir                              = $(includedir)/system
@@ -118,6 +119,7 @@ check_PROGRAMS                                       += \
     TestSystemObject                                    \
     TestSystemPacketBuffer                              \
     TestSystemTimer                                     \
+    TestTimeSource                                      \
     $(NULL)
 
 endif # CHIP_DEVICE_LAYER_TARGET_ESP32
@@ -144,6 +146,9 @@ TestSystemPacketBuffer_LDADD                          = $(COMMON_LDADD)
 TestSystemTimer_SOURCES                               = TestSystemTimerDriver.cpp
 TestSystemTimer_LDADD                                 = $(COMMON_LDADD)
 
+TestTimeSource_SOURCES                               = TestTimeSourceDriver.cpp
+TestTimeSource_LDADD                                 = $(COMMON_LDADD)
+
 #
 # Foreign make dependencies
 #

src/system/tests/TestSystemLayer.h

@@ -33,6 +33,7 @@ int TestSystemErrorStr(void);
 int TestSystemObject(void);
 int TestSystemPacketBuffer(void);
 int TestSystemTimer(void);
+int TestTimeSource(void);
 
 #ifdef __cplusplus
 }

src/system/tests/TestTimeSource.cpp

@@ -0,0 +1,98 @@
+/*
+ *
+ *    Copyright (c) 2020 Project CHIP Authors
+ *
+ *    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.
+ */
+
+/**
+ * @file
+ *    This is a unit test suite for <tt>chip::Time::TimeSource</tt>. Tests mainly
+ *    the ability to compile and use the test implementation of the time source.
+ */
+
+#ifndef __STDC_LIMIT_MACROS
+#define __STDC_LIMIT_MACROS
+#endif
+// config
+#include <system/SystemConfig.h>
+
+// module header
+#include "TestSystemLayer.h"
+
+#include <nlunit-test.h>
+#include <support/CodeUtils.h>
+#include <support/ErrorStr.h>
+#include <support/TestUtils.h>
+#include <system/TimeSource.h>
+
+namespace {
+
+void TestTimeSourceSetAndGet(nlTestSuite * inSuite, void * inContext)
+{
+
+    chip::Time::TimeSource<chip::Time::Source::kTest> source;
+
+    NL_TEST_ASSERT(inSuite, source.GetCurrentMonotonicTimeMs() == 0);
+
+    source.SetCurrentMonotonicTimeMs(1234);
+    NL_TEST_ASSERT(inSuite, source.GetCurrentMonotonicTimeMs() == 1234);
+}
+
+void SystemTimeSourceGet(nlTestSuite * inSuite, void * inContext)
+{
+
+    chip::Time::TimeSource<chip::Time::Source::kSystem> source;
+
+    uint64_t oldValue = source.GetCurrentMonotonicTimeMs();
+
+    // a basic monotonic test. This is likely to take less than 1ms, so the
+    // actual test value lies mostly in ensuring things compile.
+    for (int i = 0; i < 100; i++)
+    {
+        uint64_t newValue = source.GetCurrentMonotonicTimeMs();
+        NL_TEST_ASSERT(inSuite, newValue >= oldValue);
+        oldValue = newValue;
+    }
+}
+
+} // namespace
+
+/**
+ *   Test Suite. It lists all the test functions.
+ */
+// clang-format off
+static const nlTest sTests[] =
+{
+    NL_TEST_DEF("TimeSource<Test>::SetAndGet", TestTimeSourceSetAndGet),
+    NL_TEST_DEF("TimeSource<System>::SetAndGet", SystemTimeSourceGet),
+    NL_TEST_SENTINEL()
+};
+// clang-format on
+
+int TestTimeSource(void)
+{
+    nlTestSuite theSuite = {
+        "chip-timesource", &sTests[0], NULL /* setup */, NULL /* teardown */
+    };
+
+    // Run test suit againt one context.
+    nlTestRunner(&theSuite, NULL /* context */);
+
+    return (nlTestRunnerStats(&theSuite));
+}
+
+static void __attribute__((constructor)) TestTimeSourceCtor(void)
+{
+    VerifyOrDie(chip::RegisterUnitTests(&TestTimeSource) == CHIP_NO_ERROR);
+}

src/system/tests/TestTimeSourceDriver.cpp

@@ -0,0 +1,36 @@
+/*
+ *
+ *    Copyright (c) 2020 Project CHIP Authors
+ *
+ *    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.
+ */
+
+/**
+ *    @file
+ *      This file implements a standalone/native program executable
+ *      test driver for the CHIP system layer library timer unit
+ *      tests.
+ *
+ */
+
+#include "TestSystemLayer.h"
+
+#include <nlunit-test.h>
+
+int main(int argc, char * argv[])
+{
+    // Generate machine-readable, comma-separated value (CSV) output.
+    nlTestSetOutputStyle(OUTPUT_CSV);
+
+    return TestTimeSource();
+}