Source/cmFileTime.cxx

   1 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   2    file Copyright.txt or https://cmake.org/licensing for details.  */
   3 #include "cmFileTime.h"
   4
   5 #include <string>
   6
   7 // Use a platform-specific API to get file times efficiently.
   8 #if !defined(_WIN32) || defined(__CYGWIN__)
   9 #  include "cm_sys_stat.h"
  10 #else
  11 #  include <windows.h>
  12
  13 #  include "cmsys/Encoding.hxx"
  14 #endif
  15
  16 bool cmFileTime::Load(std::string const& fileName)
  17 {
  18 #if !defined(_WIN32) || defined(__CYGWIN__)
  19   // POSIX version.  Use the stat function.
  20   struct stat fst;
  21   if (::stat(fileName.c_str(), &fst) != 0) {
  22     return false;
  23   }
  24 #  if CMake_STAT_HAS_ST_MTIM
  25   // Nanosecond resolution
  26   this->Time = fst.st_mtim.tv_sec * UtPerS + fst.st_mtim.tv_nsec;
  27 #  elif CMake_STAT_HAS_ST_MTIMESPEC
  28   // Nanosecond resolution
  29   this->Time = fst.st_mtimespec.tv_sec * UtPerS + fst.st_mtimespec.tv_nsec;
  30 #  else
  31   // Second resolution
  32   this->Time = fst.st_mtime * UtPerS;
  33 #  endif
  34 #else
  35   // Windows version.  Get the modification time from extended file attributes.
  36   WIN32_FILE_ATTRIBUTE_DATA fdata;
  37   if (!GetFileAttributesExW(cmsys::Encoding::ToWide(fileName).c_str(),
  38                             GetFileExInfoStandard, &fdata)) {
  39     return false;
  40   }
  41
  42   // Copy the file time to the output location.
  43   using uint64 = unsigned long long;
  44
  45   this->Time = static_cast<TimeType>(
  46     (uint64(fdata.ftLastWriteTime.dwHighDateTime) << 32) +
  47     fdata.ftLastWriteTime.dwLowDateTime);
  48 #endif
  49   return true;
  50 }