3.9

1 files changed, 421 insertions, 0 deletions

diff --git a/shared/file_traverser.cpp b/shared/file_traverser.cpp
new file mode 100644
index 00000000..8e9d5f0d
--- /dev/null
+++ b/shared/file_traverser.cpp
@@ -0,0 +1,421 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) 2008-2010 ZenJu (zhnmju123 AT gmx.de)                    *
+// **************************************************************************
+//
+#include "file_traverser.h"
+#include "system_constants.h"
+#include "system_func.h"
+#include <wx/intl.h>
+#include "string_conv.h"
+#include <boost/shared_ptr.hpp>
+#include <boost/scoped_array.hpp>
+
+#ifdef FFS_WIN
+#include <wx/msw/wrapwin.h> //includes "windows.h"
+#include "WinIoCtl.h"
+#include "long_path_prefix.h"
+
+#elif defined FFS_LINUX
+#include <sys/stat.h>
+#include <dirent.h>
+#include <cerrno>
+#endif
+
+
+//Note: this class is superfluous for 64 bit applications!
+//class DisableWow64Redirection
+//{
+//public:
+//    DisableWow64Redirection() :
+//        wow64DisableWow64FsRedirection(util::loadDllFunction<Wow64DisableWow64FsRedirectionFunc>(L"kernel32.dll", "Wow64DisableWow64FsRedirection")),
+//        wow64RevertWow64FsRedirection(util::loadDllFunction<Wow64RevertWow64FsRedirectionFunc>(L"kernel32.dll", "Wow64RevertWow64FsRedirection")),
+//        oldValue(NULL)
+//    {
+//        if (    wow64DisableWow64FsRedirection &&
+//                wow64RevertWow64FsRedirection)
+//            (*wow64DisableWow64FsRedirection)(&oldValue); //__out  PVOID *OldValue
+//    }
+//
+//    ~DisableWow64Redirection()
+//    {
+//        if (    wow64DisableWow64FsRedirection &&
+//                wow64RevertWow64FsRedirection)
+//            (*wow64RevertWow64FsRedirection)(oldValue); //__in  PVOID OldValue
+//    }
+//
+//private:
+//    typedef BOOL (WINAPI *Wow64DisableWow64FsRedirectionFunc)(PVOID* OldValue);
+//    typedef BOOL (WINAPI *Wow64RevertWow64FsRedirectionFunc)(PVOID OldValue);
+//
+//    const Wow64DisableWow64FsRedirectionFunc wow64DisableWow64FsRedirection;
+//    const Wow64RevertWow64FsRedirectionFunc  wow64RevertWow64FsRedirection;
+//
+//    PVOID oldValue;
+//};
+
+#ifdef _MSC_VER //I don't have Windows Driver Kit at hands right now, so unfortunately we need to redefine this structures and cross fingers...
+typedef struct _REPARSE_DATA_BUFFER
+{
+    ULONG  ReparseTag;
+    USHORT ReparseDataLength;
+    USHORT Reserved;
+    union
+    {
+        struct
+        {
+            USHORT SubstituteNameOffset;
+            USHORT SubstituteNameLength;
+            USHORT PrintNameOffset;
+            USHORT PrintNameLength;
+            ULONG  Flags;
+            WCHAR  PathBuffer[1];
+        } SymbolicLinkReparseBuffer;
+        struct
+        {
+            USHORT SubstituteNameOffset;
+            USHORT SubstituteNameLength;
+            USHORT PrintNameOffset;
+            USHORT PrintNameLength;
+            WCHAR  PathBuffer[1];
+        } MountPointReparseBuffer;
+        struct
+        {
+            UCHAR DataBuffer[1];
+        } GenericReparseBuffer;
+    };
+} REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;
+#define REPARSE_DATA_BUFFER_HEADER_SIZE   FIELD_OFFSET(REPARSE_DATA_BUFFER, GenericReparseBuffer)
+#endif
+
+
+Zstring getSymlinkTarget(const Zstring& linkPath) //throw(); returns empty string on error
+{
+#ifdef FFS_WIN
+//FSCTL_GET_REPARSE_POINT: http://msdn.microsoft.com/en-us/library/aa364571(VS.85).aspx
+
+    const HANDLE hLink = ::CreateFile(linkPath.c_str(),
+                                      GENERIC_READ,
+                                      FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+                                      NULL,
+                                      OPEN_EXISTING,
+                                      FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OPEN_REPARSE_POINT,
+                                      NULL);
+    if (hLink == INVALID_HANDLE_VALUE)
+        return Zstring();
+
+    boost::shared_ptr<void> dummy(hLink, ::CloseHandle);
+
+    //respect alignment issues...
+    const size_t bufferSize = REPARSE_DATA_BUFFER_HEADER_SIZE + MAXIMUM_REPARSE_DATA_BUFFER_SIZE;
+    boost::scoped_array<char> buffer(new char[bufferSize]);
+
+    DWORD bytesReturned; //dummy value required by FSCTL_GET_REPARSE_POINT!
+    if (!::DeviceIoControl(hLink,                   //__in         HANDLE hDevice,
+                           FSCTL_GET_REPARSE_POINT, //__in         DWORD dwIoControlCode,
+                           NULL,                    //__in_opt     LPVOID lpInBuffer,
+                           0,                       //__in         DWORD nInBufferSize,
+                           buffer.get(),            //__out_opt    LPVOID lpOutBuffer,
+                           bufferSize,              //__in         DWORD nOutBufferSize,
+                           &bytesReturned,          //__out_opt    LPDWORD lpBytesReturned,
+                           NULL))                   //__inout_opt  LPOVERLAPPED lpOverlapped
+        return Zstring();
+
+    REPARSE_DATA_BUFFER& reparseData = *reinterpret_cast<REPARSE_DATA_BUFFER*>(buffer.get()); //REPARSE_DATA_BUFFER needs to be artificially enlarged!
+
+    if (reparseData.ReparseTag == IO_REPARSE_TAG_SYMLINK)
+        return Zstring(reparseData.SymbolicLinkReparseBuffer.PathBuffer + reparseData.SymbolicLinkReparseBuffer.SubstituteNameOffset / sizeof(WCHAR),
+                       reparseData.SymbolicLinkReparseBuffer.SubstituteNameLength / sizeof(WCHAR));
+    else if (reparseData.ReparseTag == IO_REPARSE_TAG_MOUNT_POINT)
+        return Zstring(reparseData.MountPointReparseBuffer.PathBuffer + reparseData.MountPointReparseBuffer.SubstituteNameOffset / sizeof(WCHAR),
+                       reparseData.MountPointReparseBuffer.SubstituteNameLength / sizeof(WCHAR));
+    else
+        return Zstring(); //unknown reparse point
+
+#elif defined FFS_LINUX
+    const int BUFFER_SIZE = 10000;
+    char buffer[BUFFER_SIZE];
+
+    const int bytesWritten = ::readlink(linkPath.c_str(), buffer, BUFFER_SIZE);
+    if (bytesWritten < 0 || bytesWritten >= BUFFER_SIZE)
+        return Zstring(); //error
+
+    buffer[bytesWritten] = 0; //set null-terminating char
+
+    return buffer;
+#endif
+}
+
+
+#ifdef FFS_WIN
+inline
+wxLongLong getWin32TimeInformation(const FILETIME& lastWriteTime)
+{
+    //convert UTC FILETIME to ANSI C format (number of seconds since Jan. 1st 1970 UTC)
+    wxLongLong writeTimeLong(wxInt32(lastWriteTime.dwHighDateTime), lastWriteTime.dwLowDateTime);
+    writeTimeLong /= 10000000;                    //reduce precision to 1 second (FILETIME has unit 10^-7 s)
+    writeTimeLong -= wxLongLong(2, 3054539008UL); //timeshift between ansi C time and FILETIME in seconds == 11644473600s
+    return writeTimeLong;
+}
+
+
+inline
+void setWin32FileInformation(const FILETIME& lastWriteTime,
+                             const DWORD fileSizeHigh,
+                             const DWORD fileSizeLow,
+                             ffs3::TraverseCallback::FileInfo& output)
+{
+    output.lastWriteTimeRaw = getWin32TimeInformation(lastWriteTime);
+    output.fileSize = wxULongLong(fileSizeHigh, fileSizeLow);
+}
+
+
+inline
+bool setWin32FileInformationFromSymlink(const Zstring& linkName, ffs3::TraverseCallback::FileInfo& output)
+{
+    //open handle to target of symbolic link
+    HANDLE hFile = ::CreateFile(ffs3::applyLongPathPrefix(linkName).c_str(),
+                                0,
+                                FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+                                NULL,
+                                OPEN_EXISTING,
+                                FILE_FLAG_BACKUP_SEMANTICS,
+                                NULL);
+    if (hFile == INVALID_HANDLE_VALUE)
+        return false;
+
+    boost::shared_ptr<void> dummy(hFile, ::CloseHandle);
+
+    BY_HANDLE_FILE_INFORMATION fileInfoByHandle;
+    if (!::GetFileInformationByHandle(hFile, &fileInfoByHandle))
+        return false;
+
+    //write output
+    setWin32FileInformation(fileInfoByHandle.ftLastWriteTime, fileInfoByHandle.nFileSizeHigh, fileInfoByHandle.nFileSizeLow, output);
+    return true;
+}
+#endif
+
+
+template <bool followSymlinks>
+void traverseDirectory(const Zstring& directory, ffs3::TraverseCallback* sink, int level)
+{
+    using namespace ffs3;
+
+    if (level == 100) //catch endless recursion
+    {
+        sink->onError(wxString(_("Endless loop when traversing directory:")) + wxT("\n\"") + zToWx(directory) + wxT("\""));
+        return;
+    }
+
+#ifdef FFS_WIN
+    //ensure directoryFormatted ends with backslash
+    const Zstring directoryFormatted = directory.EndsWith(common::FILE_NAME_SEPARATOR) ?
+                                       directory :
+                                       directory + common::FILE_NAME_SEPARATOR;
+
+    WIN32_FIND_DATA fileMetaData;
+    HANDLE searchHandle = ::FindFirstFile(applyLongPathPrefix(directoryFormatted + DefaultChar('*')).c_str(), //__in   LPCTSTR lpFileName
+                                          &fileMetaData);                                                     //__out  LPWIN32_FIND_DATA lpFindFileData
+    //no noticable performance difference compared to FindFirstFileEx with FindExInfoBasic, FIND_FIRST_EX_CASE_SENSITIVE and/or FIND_FIRST_EX_LARGE_FETCH
+
+    if (searchHandle == INVALID_HANDLE_VALUE)
+    {
+        const DWORD lastError = ::GetLastError();
+        if (lastError == ERROR_FILE_NOT_FOUND)
+            return;
+
+        //else: we have a problem... report it:
+        const wxString errorMessage = wxString(_("Error traversing directory:")) + wxT("\n\"") + zToWx(directory) + wxT("\"") + wxT("\n\n") +
+                                      ffs3::getLastErrorFormatted(lastError);
+
+        sink->onError(errorMessage);
+        return;
+    }
+
+    boost::shared_ptr<void> dummy(searchHandle, ::FindClose);
+
+    do
+    {
+        //don't return "." and ".."
+        const wxChar* const shortName = fileMetaData.cFileName;
+        if (     shortName[0] == wxChar('.') &&
+                 ((shortName[1] == wxChar('.') && shortName[2] == wxChar('\0')) ||
+                  shortName[1] == wxChar('\0')))
+            continue;
+
+        const Zstring fullName = directoryFormatted + shortName;
+
+        const bool isSymbolicLink = (fileMetaData.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) != 0;
+
+        if (isSymbolicLink && !followSymlinks) //evaluate symlink directly
+        {
+            TraverseCallback::SymlinkInfo details;
+            details.lastWriteTimeRaw = getWin32TimeInformation(fileMetaData.ftLastWriteTime);
+            details.targetPath       = getSymlinkTarget(fullName); //throw(); returns empty string on error
+            details.dirLink          = (fileMetaData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0; //directory symlinks have this flag on Windows
+            sink->onSymlink(shortName, fullName, details);
+        }
+        else if (fileMetaData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) //a directory... or symlink that needs to be followed (for directory symlinks this flag is set too!)
+        {
+            const TraverseCallback::ReturnValDir rv = sink->onDir(shortName, fullName);
+            switch (rv.returnCode)
+            {
+            case TraverseCallback::ReturnValDir::TRAVERSING_DIR_IGNORE:
+                break;
+
+            case TraverseCallback::ReturnValDir::TRAVERSING_DIR_CONTINUE:
+                traverseDirectory<followSymlinks>(fullName, rv.subDirCb, level + 1);
+                break;
+            }
+        }
+        else //a file or symlink that is followed...
+        {
+            TraverseCallback::FileInfo details;
+
+            if (isSymbolicLink) //dereference symlinks!
+            {
+                if (!setWin32FileInformationFromSymlink(fullName, details))
+                {
+                    //broken symlink...
+                    details.lastWriteTimeRaw = 0; //we are not interested in the modifiation time of the link
+                    details.fileSize         = 0;
+                }
+            }
+            else
+                setWin32FileInformation(fileMetaData.ftLastWriteTime, fileMetaData.nFileSizeHigh, fileMetaData.nFileSizeLow, details);
+
+            sink->onFile(shortName, fullName, details);
+        }
+    }
+    while (::FindNextFile(searchHandle,	   // handle to search
+                          &fileMetaData)); // pointer to structure for data on found file
+
+    const DWORD lastError = ::GetLastError();
+    if (lastError == ERROR_NO_MORE_FILES)
+        return; //everything okay
+
+    //else: we have a problem... report it:
+    const wxString errorMessage = wxString(_("Error traversing directory:")) + wxT("\n\"") + zToWx(directory) + wxT("\"") ;
+    sink->onError(errorMessage + wxT("\n\n") + ffs3::getLastErrorFormatted(lastError));
+    return;
+
+#elif defined FFS_LINUX
+    DIR* dirObj = ::opendir(directory.c_str()); //directory must NOT end with path separator, except "/"
+    if (dirObj == NULL)
+    {
+        const wxString errorMessage = wxString(_("Error traversing directory:")) + wxT("\n\"") + zToWx(directory) + wxT("\"") ;
+        sink->onError(errorMessage + wxT("\n\n") + ffs3::getLastErrorFormatted());
+        return;
+    }
+
+    boost::shared_ptr<DIR> dummy(dirObj, &::closedir); //never close NULL handles! -> crash
+
+    while (true)
+    {
+        errno = 0; //set errno to 0 as unfortunately this isn't done when readdir() returns NULL because it can't find any files
+        struct dirent* dirEntry = ::readdir(dirObj);
+        if (dirEntry == NULL)
+        {
+            if (errno == 0)
+                return; //everything okay
+
+            //else: we have a problem... report it:
+            const wxString errorMessage = wxString(_("Error traversing directory:")) + wxT("\n\"") + zToWx(directory) + wxT("\"") ;
+            sink->onError(errorMessage + wxT("\n\n") + ffs3::getLastErrorFormatted());
+            return;
+        }
+
+        //don't return "." and ".."
+        const DefaultChar* const shortName = dirEntry->d_name;
+        if (      shortName[0] == wxChar('.') &&
+                  ((shortName[1] == wxChar('.') && shortName[2] == wxChar('\0')) ||
+                   shortName[1] == wxChar('\0')))
+            continue;
+
+        const Zstring fullName = directory.EndsWith(common::FILE_NAME_SEPARATOR) ? //e.g. "/"
+                                 directory + shortName :
+                                 directory + common::FILE_NAME_SEPARATOR + shortName;
+
+        struct stat fileInfo;
+        if (::lstat(fullName.c_str(), &fileInfo) != 0) //lstat() does not resolve symlinks
+        {
+            const wxString errorMessage = wxString(_("Error reading file attributes:")) + wxT("\n\"") + zToWx(fullName) + wxT("\"");
+            sink->onError(errorMessage + wxT("\n\n") + ffs3::getLastErrorFormatted());
+            continue;
+        }
+
+        const bool isSymbolicLink = S_ISLNK(fileInfo.st_mode);
+
+        if (isSymbolicLink)
+        {
+            if (followSymlinks) //on Linux Symlinks need to be followed to evaluate whether they point to a file or directory
+            {
+                if (::stat(fullName.c_str(), &fileInfo) != 0) //stat() resolves symlinks
+                {
+                    //a broken symbolic link
+                    TraverseCallback::FileInfo details;
+                    details.lastWriteTimeRaw = 0; //we are not interested in the modifiation time of the link
+                    details.fileSize         = 0;
+                    sink->onFile(shortName, fullName, details); //report broken symlink as file!
+                    continue;
+                }
+            }
+            else //evaluate symlink directly
+            {
+                TraverseCallback::SymlinkInfo details;
+                details.lastWriteTimeRaw = fileInfo.st_mtime; //UTC time(ANSI C format); unit: 1 second
+                details.targetPath       = getSymlinkTarget(fullName); //throw(); returns empty string on error
+                details.dirLink          = ::stat(fullName.c_str(), &fileInfo) == 0 && S_ISDIR(fileInfo.st_mode); //S_ISDIR and S_ISLNK are mutually exclusive on Linux => need to follow link
+                sink->onSymlink(shortName, fullName, details);
+                continue;
+            }
+        }
+
+        //fileInfo contains dereferenced data in any case from here on
+
+        if (S_ISDIR(fileInfo.st_mode)) //a directory... cannot be a symlink on Linux in this case
+        {
+            const TraverseCallback::ReturnValDir rv = sink->onDir(shortName, fullName);
+            switch (rv.returnCode)
+            {
+            case TraverseCallback::ReturnValDir::TRAVERSING_DIR_IGNORE:
+                break;
+
+            case TraverseCallback::ReturnValDir::TRAVERSING_DIR_CONTINUE:
+                traverseDirectory<followSymlinks>(fullName, rv.subDirCb, level + 1);
+                break;
+            }
+        }
+        else //a file... (or symlink; pathological!)
+        {
+            TraverseCallback::FileInfo details;
+            details.lastWriteTimeRaw = fileInfo.st_mtime; //UTC time(ANSI C format); unit: 1 second
+            details.fileSize         = fileInfo.st_size;
+
+            sink->onFile(shortName, fullName, details);
+        }
+    }
+#endif
+}
+
+
+void ffs3::traverseFolder(const Zstring& directory,
+                                  bool followSymlinks,
+                                  TraverseCallback* sink)
+{
+#ifdef FFS_WIN
+    const Zstring& directoryFormatted = directory;
+#elif defined FFS_LINUX
+    const Zstring directoryFormatted = //remove trailing slash
+        directory.size() > 1 && directory.EndsWith(common::FILE_NAME_SEPARATOR) ?  //exception: allow '/'
+        directory.BeforeLast(common::FILE_NAME_SEPARATOR) :
+        directory;
+#endif
+
+    if (followSymlinks)
+        traverseDirectory<true>(directoryFormatted, sink, 0);
+    else
+        traverseDirectory<false>(directoryFormatted, sink, 0);
+}