From 54318729c1531563ebf875227ede53f092e525c0 Mon Sep 17 00:00:00 2001
From: bluebin14 <80577827+bluebin14@users.noreply.github.com>
Date: Mon, 25 Apr 2022 16:12:59 +0200
Subject: [PATCH] Linux: add support for GetClock_RealTimeMS (#17672)

* Linux: add support for GetClock_RealTimeMS

* Simplified GetClock_RealTimeMS logic
---
 src/platform/Linux/SystemTimeSupport.cpp | 43 ++++++++++++++++++++++--
 1 file changed, 40 insertions(+), 3 deletions(-)

diff --git a/src/platform/Linux/SystemTimeSupport.cpp b/src/platform/Linux/SystemTimeSupport.cpp
index a4b5ec0b75229a..d30a51bd575bd3 100644
--- a/src/platform/Linux/SystemTimeSupport.cpp
+++ b/src/platform/Linux/SystemTimeSupport.cpp
@@ -52,17 +52,54 @@ Milliseconds64 ClockImpl::GetMonotonicMilliseconds64()
 
 CHIP_ERROR ClockImpl::GetClock_RealTime(Clock::Microseconds64 & aCurTime)
 {
-    return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
+    struct timeval tv;
+    if (gettimeofday(&tv, nullptr) != 0)
+    {
+        return CHIP_ERROR_POSIX(errno);
+    }
+    if (tv.tv_sec < CHIP_SYSTEM_CONFIG_VALID_REAL_TIME_THRESHOLD)
+    {
+        return CHIP_ERROR_REAL_TIME_NOT_SYNCED;
+    }
+    if (tv.tv_usec < 0)
+    {
+        return CHIP_ERROR_REAL_TIME_NOT_SYNCED;
+    }
+    static_assert(CHIP_SYSTEM_CONFIG_VALID_REAL_TIME_THRESHOLD >= 0, "We might be letting through negative tv_sec values!");
+    aCurTime = Clock::Microseconds64((static_cast<uint64_t>(tv.tv_sec) * UINT64_C(1000000)) + static_cast<uint64_t>(tv.tv_usec));
+    return CHIP_NO_ERROR;
 }
 
 CHIP_ERROR ClockImpl::GetClock_RealTimeMS(Clock::Milliseconds64 & aCurTime)
 {
-    return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
+    Clock::Microseconds64 curTimeUs;
+    CHIP_ERROR err = GetClock_RealTime(curTimeUs);
+    if (err == CHIP_NO_ERROR)
+    {
+        aCurTime = std::chrono::duration_cast<Clock::Milliseconds64>(curTimeUs);
+    }
+    return err;
 }
 
 CHIP_ERROR ClockImpl::SetClock_RealTime(Clock::Microseconds64 aNewCurTime)
 {
-    return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
+    struct timeval tv;
+    tv.tv_sec  = static_cast<time_t>(aNewCurTime.count() / UINT64_C(1000000));
+    tv.tv_usec = static_cast<long>(aNewCurTime.count() % UINT64_C(1000000));
+    if (settimeofday(&tv, nullptr) != 0)
+    {
+        return (errno == EPERM) ? CHIP_ERROR_ACCESS_DENIED : CHIP_ERROR_POSIX(errno);
+    }
+#if CHIP_PROGRESS_LOGGING
+    {
+        const time_t timep = tv.tv_sec;
+        struct tm calendar;
+        localtime_r(&timep, &calendar);
+        ChipLogProgress(DeviceLayer, "Real time clock set to %ld (%04d/%02d/%02d %02d:%02d:%02d UTC)", tv.tv_sec, calendar.tm_year,
+                        calendar.tm_mon, calendar.tm_mday, calendar.tm_hour, calendar.tm_min, calendar.tm_sec);
+    }
+#endif // CHIP_PROGRESS_LOGGING
+    return CHIP_NO_ERROR;
 }
 
 } // namespace Clock