Added last_modified() method to dlib::file.

dlib/dir_nav/dir_nav_kernel_2.cpp

@@ -62,6 +62,12 @@ namespace dlib
         else
         {
             state.file_size = static_cast<uint64>(buffer.st_size);
+
+
+            state.last_modified = std::chrono::system_clock::from_time_t(buffer.st_mtime);
+#ifdef _BSD_SOURCE 
+            state.last_modified += std::chrono::nanoseconds(buffer.st_atim.tv_nsec);
+#endif
         }
 
     }

dlib/dir_nav/dir_nav_kernel_2.h

@@ -22,6 +22,7 @@
 #include <sys/stat.h>
 #include <errno.h>
 #include <stdlib.h>
+#include <chrono>
 
 #if !defined(__USE_LARGEFILE64 ) && !defined(_LARGEFILE64_SOURCE)
 #define stat64 stat
@@ -63,6 +64,7 @@ namespace dlib
             uint64 file_size;
             std::string name;
             std::string full_name;
+            std::chrono::time_point<std::chrono::system_clock> last_modified;
         };
 
         void init(const std::string& name);
@@ -74,12 +76,14 @@ namespace dlib
             const std::string& name,
             const std::string& full_name,
             const uint64 file_size,
+            const std::chrono::time_point<std::chrono::system_clock>& last_modified,
             private_constructor
         )
         {
             state.file_size = file_size;
             state.name = name;
             state.full_name = full_name;
+            state.last_modified = last_modified;
         }
 
 
@@ -110,6 +114,9 @@ namespace dlib
         inline uint64 size (
         ) const { return state.file_size; }
 
+        inline std::chrono::time_point<std::chrono::system_clock> last_modified (
+        ) const { return state.last_modified; }
+
         operator std::string (
         ) const { return full_name(); }
 
@@ -383,6 +390,10 @@ namespace dlib
                 {
                     file_size = static_cast<uint64>(buffer.st_size);
                 }
+                auto last_modified = std::chrono::system_clock::from_time_t(buffer.st_mtime);
+#ifdef _BSD_SOURCE 
+                last_modified += std::chrono::nanoseconds(buffer.st_atim.tv_nsec);
+#endif
 
                 if (S_ISDIR(buffer.st_mode) == 0)
                 {
@@ -391,6 +402,7 @@ namespace dlib
                         data->d_name,
                         path+data->d_name,
                         file_size,
+                        last_modified,
                         file::private_constructor()
                         );
                     files.enqueue(temp);