Implement command GetDateTime

This commit implements the GetDateTime command which is
defined in PLDM Bios Control and Configuration Specification.

Change-Id: Iced21bbad7be07d357b6885b1b1e03b07a3da165
Signed-off-by: Sampa Misra <sampmisr@in.ibm.com>
diff --git a/test/libpldm_bios_test.cpp b/test/libpldm_bios_test.cpp
new file mode 100644
index 0000000..b1771c9
--- /dev/null
+++ b/test/libpldm_bios_test.cpp
@@ -0,0 +1,118 @@
+#include <string.h>
+
+#include <array>
+
+#include "libpldm/base.h"
+#include "libpldm/bios.h"
+
+#include <gtest/gtest.h>
+
+TEST(GetDateTime, testEncodeRequest)
+{
+    pldm_msg request{};
+    request.body.payload = nullptr;
+    request.body.payload_length = 0;
+
+    auto rc = encode_get_date_time_req(0, &request);
+    ASSERT_EQ(rc, PLDM_SUCCESS);
+}
+
+TEST(GetDateTime, testEncodeResponse)
+{
+    uint8_t completionCode = 0;
+    uint8_t seconds = 50;
+    uint8_t minutes = 20;
+    uint8_t hours = 5;
+    uint8_t day = 23;
+    uint8_t month = 11;
+    uint16_t year = 2019;
+
+    std::array<uint8_t, PLDM_GET_DATE_TIME_RESP_BYTES> responseMsg{};
+    pldm_msg response{};
+
+    response.body.payload = responseMsg.data();
+    response.body.payload_length = responseMsg.size();
+
+    auto rc = encode_get_date_time_resp(0, PLDM_SUCCESS, seconds, minutes,
+                                        hours, day, month, year, &response);
+
+    ASSERT_EQ(rc, PLDM_SUCCESS);
+    ASSERT_EQ(completionCode, response.body.payload[0]);
+
+    ASSERT_EQ(0,
+              memcmp(response.body.payload + sizeof(response.body.payload[0]),
+                     &seconds, sizeof(seconds)));
+    ASSERT_EQ(0, memcmp(response.body.payload +
+                            sizeof(response.body.payload[0]) + sizeof(seconds),
+                        &minutes, sizeof(minutes)));
+    ASSERT_EQ(0,
+              memcmp(response.body.payload + sizeof(response.body.payload[0]) +
+                         sizeof(seconds) + sizeof(minutes),
+                     &hours, sizeof(hours)));
+    ASSERT_EQ(0,
+              memcmp(response.body.payload + sizeof(response.body.payload[0]) +
+                         sizeof(seconds) + sizeof(minutes) + sizeof(hours),
+                     &day, sizeof(day)));
+    ASSERT_EQ(0, memcmp(response.body.payload +
+                            sizeof(response.body.payload[0]) + sizeof(seconds) +
+                            sizeof(minutes) + sizeof(hours) + sizeof(day),
+                        &month, sizeof(month)));
+    ASSERT_EQ(0,
+              memcmp(response.body.payload + sizeof(response.body.payload[0]) +
+                         sizeof(seconds) + sizeof(minutes) + sizeof(hours) +
+                         sizeof(day) + sizeof(month),
+                     &year, sizeof(year)));
+}
+
+TEST(GetDateTime, testDecodeResponse)
+{
+    std::array<uint8_t, PLDM_GET_DATE_TIME_RESP_BYTES> responseMsg{};
+    pldm_msg_payload response{};
+    response.payload = responseMsg.data();
+    response.payload_length = responseMsg.size();
+
+    uint8_t completionCode = 0;
+
+    uint8_t seconds = 55;
+    uint8_t minutes = 2;
+    uint8_t hours = 8;
+    uint8_t day = 9;
+    uint8_t month = 7;
+    uint16_t year = 2020;
+
+    uint8_t retSeconds = 0;
+    uint8_t retMinutes = 0;
+    uint8_t retHours = 0;
+    uint8_t retDay = 0;
+    uint8_t retMonth = 0;
+    uint16_t retYear = 0;
+
+    memcpy(response.payload + sizeof(completionCode), &seconds,
+           sizeof(seconds));
+    memcpy(response.payload + sizeof(completionCode) + sizeof(seconds),
+           &minutes, sizeof(minutes));
+    memcpy(response.payload + sizeof(completionCode) + sizeof(seconds) +
+               sizeof(minutes),
+           &hours, sizeof(hours));
+    memcpy(response.payload + sizeof(completionCode) + sizeof(seconds) +
+               sizeof(minutes) + sizeof(hours),
+           &day, sizeof(day));
+    memcpy(response.payload + sizeof(completionCode) + sizeof(seconds) +
+               sizeof(minutes) + sizeof(hours) + sizeof(day),
+           &month, sizeof(month));
+    memcpy(response.payload + sizeof(completionCode) + sizeof(seconds) +
+               sizeof(minutes) + sizeof(hours) + sizeof(day) + sizeof(month),
+           &year, sizeof(year));
+
+    auto rc = decode_get_date_time_resp(&response, &completionCode, &retSeconds,
+                                        &retMinutes, &retHours, &retDay,
+                                        &retMonth, &retYear);
+
+    ASSERT_EQ(rc, PLDM_SUCCESS);
+    ASSERT_EQ(seconds, retSeconds);
+    ASSERT_EQ(minutes, retMinutes);
+    ASSERT_EQ(hours, retHours);
+    ASSERT_EQ(day, retDay);
+    ASSERT_EQ(month, retMonth);
+    ASSERT_EQ(year, retYear);
+}