3 files changed, 16 insertions, 0 deletions
diff --git a/base/file_util.h b/base/file_util.h
index bf5f5bf..a6914b7 100644
--- a/base/file_util.h
+++ b/base/file_util.h
@@ -531,6 +531,10 @@ bool RenameFileAndResetSecurityDescriptor(
     const FilePath& source_file_path,
     const FilePath& target_file_path);
 
+// Returns whether the file has been modified since a particular date.
+bool HasFileBeenModifiedSince(const FileEnumerator::FindInfo& find_info,
+                              const base::Time& cutoff_time);
+
 }  // namespace file_util
 
 #endif  // BASE_FILE_UTIL_H_
diff --git a/base/file_util_posix.cc b/base/file_util_posix.cc
index a269d3f..dc9d793 100644
--- a/base/file_util_posix.cc
+++ b/base/file_util_posix.cc
@@ -699,4 +699,9 @@ void MemoryMappedFile::CloseHandles() {
   file_ = base::kInvalidPlatformFileValue;
 }
 
+bool HasFileBeenModifiedSince(const FileEnumerator::FindInfo& find_info,
+                              const base::Time& cutoff_time) {
+  return find_info.stat.st_mtime >= cutoff_time.ToTimeT();
+}
+
 } // namespace file_util
diff --git a/base/file_util_win.cc b/base/file_util_win.cc
index a320aca..9722e31 100644
--- a/base/file_util_win.cc
+++ b/base/file_util_win.cc
@@ -793,4 +793,11 @@ void MemoryMappedFile::CloseHandles() {
   length_ = INVALID_FILE_SIZE;
 }
 
+bool HasFileBeenModifiedSince(const FileEnumerator::FindInfo& find_info,
+                              const base::Time& cutoff_time) {
+  long result = CompareFileTime(&find_info.ftLastWriteTime,
+                                &cutoff_time.ToFileTime());
+  return result == 1 || result == 0;
+}
+
 }  // namespace file_util