1 files changed, 44 insertions, 0 deletions
diff --git a/redfish-core/src/utils/time_utils.cpp b/redfish-core/src/utils/time_utils.cpp
new file mode 100644
index 0000000000..f427ba64c4
--- /dev/null
+++ b/redfish-core/src/utils/time_utils.cpp
@@ -0,0 +1,44 @@
+#include "utils/time_utils.hpp"
+
+#include "utils/extern/date.h"
+
+#include <array>
+#include <chrono>
+#include <optional>
+#include <sstream>
+#include <string>
+#include <string_view>
+#include <version>
+
+namespace redfish::time_utils
+{
+using usSinceEpoch = std::chrono::duration<uint64_t, std::micro>;
+std::optional<usSinceEpoch> dateStringToEpoch(std::string_view datetime)
+{
+    for (const char* format : std::to_array({"%FT%T%Ez", "%FT%TZ", "%FT%T"}))
+    {
+        // Parse using signed so we can detect negative dates
+        std::chrono::sys_time<std::chrono::duration<int64_t, std::micro>> date;
+        std::istringstream iss(std::string{datetime});
+#if __cpp_lib_chrono >= 201907L
+        namespace chrono_from_stream = std::chrono;
+#else
+        namespace chrono_from_stream = date;
+#endif
+        if (chrono_from_stream::from_stream(iss, format, date))
+        {
+            if (date.time_since_epoch().count() < 0)
+            {
+                return std::nullopt;
+            }
+            if (iss.rdbuf()->in_avail() != 0)
+            {
+                // More information left at end of string.
+                continue;
+            }
+            return usSinceEpoch{date.time_since_epoch().count()};
+        }
+    }
+    return std::nullopt;
+}
+} // namespace redfish::time_utils