1 files changed, 82 insertions, 0 deletions
diff --git a/shared/fileID.cpp b/shared/fileID.cpp
new file mode 100644
index 00000000..005707dc
--- /dev/null
+++ b/shared/fileID.cpp
@@ -0,0 +1,82 @@
+#include "fileID.h"
+
+#ifdef FFS_WIN
+#include "staticAssert.h"
+#include <wx/msw/wrapwin.h> //includes "windows.h"
+#include "longPathPrefix.h"
+
+#elif defined FFS_LINUX
+
+#endif
+
+
+
+#ifdef FFS_WIN
+class CloseHandleOnExit
+{
+public:
+    CloseHandleOnExit(HANDLE fileHandle) : fileHandle_(fileHandle) {}
+
+    ~CloseHandleOnExit()
+    {
+        ::CloseHandle(fileHandle_);
+    }
+
+private:
+    HANDLE fileHandle_;
+};
+
+
+Utility::FileID Utility::retrieveFileID(const Zstring& filename)
+{
+    //ensure our DWORD_FFS really is the same as DWORD
+    assert_static(sizeof(Utility::FileID::DWORD_FFS) == sizeof(DWORD));
+
+//WARNING: CreateFile() is SLOW, while GetFileInformationByHandle() is quite cheap!
+//http://msdn.microsoft.com/en-us/library/aa363788(VS.85).aspx
+
+    const HANDLE hFile = ::CreateFile(FreeFileSync::applyLongPathPrefix(filename).c_str(),
+                                      0,
+                                      FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+                                      NULL,
+                                      OPEN_EXISTING,
+                                      FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTICS, //FILE_FLAG_BACKUP_SEMANTICS needed to open directories
+                                      NULL);
+    if (hFile != INVALID_HANDLE_VALUE)
+    {
+        CloseHandleOnExit dummy(hFile);
+
+        BY_HANDLE_FILE_INFORMATION info;
+        if (::GetFileInformationByHandle(hFile, &info))
+        {
+            return Utility::FileID(info.dwVolumeSerialNumber,
+                                   info.nFileIndexHigh,
+                                   info.nFileIndexLow);
+        }
+    }
+    return Utility::FileID(); //empty ID
+}
+
+
+#elif defined FFS_LINUX
+Utility::FileID Utility::retrieveFileID(const Zstring& filename)
+{
+    struct stat fileInfo;
+    if (::lstat(filename.c_str(), &fileInfo) == 0) //lstat() does not resolve symlinks
+        return Utility::FileID(fileInfo.st_dev, fileInfo.st_ino);
+
+    return Utility::FileID(); //empty ID
+}
+#endif
+
+
+bool Utility::sameFileSpecified(const Zstring& file1, const Zstring& file2)
+{
+    const Utility::FileID id1 = retrieveFileID(file1);
+    const Utility::FileID id2 = retrieveFileID(file2);
+
+    if (id1 != FileID() && id2 != FileID())
+        return id1 == id2;
+
+    return false;
+}