1 files changed, 49 insertions, 0 deletions
diff --git a/Source/cmFileTime.cxx b/Source/cmFileTime.cxx
new file mode 100644
index 000000000..253457ff2
--- /dev/null
+++ b/Source/cmFileTime.cxx
@@ -0,0 +1,49 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#include "cmFileTime.h"
+
+#include <string>
+#include <time.h>
+
+// Use a platform-specific API to get file times efficiently.
+#if !defined(_WIN32) || defined(__CYGWIN__)
+#  include "cm_sys_stat.h"
+#else
+#  include "cmsys/Encoding.hxx"
+#  include <windows.h>
+#endif
+
+bool cmFileTime::Load(std::string const& fileName)
+{
+#if !defined(_WIN32) || defined(__CYGWIN__)
+  // POSIX version.  Use the stat function.
+  struct stat fst;
+  if (::stat(fileName.c_str(), &fst) != 0) {
+    return false;
+  }
+#  if CMake_STAT_HAS_ST_MTIM
+  // Nanosecond resolution
+  this->NS = fst.st_mtim.tv_sec * NsPerS + fst.st_mtim.tv_nsec;
+#  elif CMake_STAT_HAS_ST_MTIMESPEC
+  // Nanosecond resolution
+  this->NS = fst.st_mtimespec.tv_sec * NsPerS + fst.st_mtimespec.tv_nsec;
+#  else
+  // Second resolution
+  this->NS = fst.st_mtime * NsPerS;
+#  endif
+#else
+  // Windows version.  Get the modification time from extended file attributes.
+  WIN32_FILE_ATTRIBUTE_DATA fdata;
+  if (!GetFileAttributesExW(cmsys::Encoding::ToWide(fileName).c_str(),
+                            GetFileExInfoStandard, &fdata)) {
+    return false;
+  }
+
+  // Copy the file time to the output location.
+  this->NS = (static_cast<NSC>(fdata.ftLastWriteTime.dwHighDateTime) << 32) |
+    static_cast<NSC>(fdata.ftLastWriteTime.dwLowDateTime);
+  // The file time resolution is 100 ns.
+  this->NS *= 100;
+#endif
+  return true;
+}