1 files changed, 112 insertions, 29 deletions

diff --git a/zen/FindFilePlus/find_file_plus.cpp b/zen/FindFilePlus/find_file_plus.cpp
index becfe553..e613177b 100644
--- a/zen/FindFilePlus/find_file_plus.cpp
+++ b/zen/FindFilePlus/find_file_plus.cpp
@@ -10,16 +10,18 @@
 #include "load_dll.h"
 #include <zen/scope_guard.h>
 
+#include <cstdio>
+
 using namespace dll;
 using namespace findplus;
 
 
 namespace
 {
-struct FileError
+struct NtFileError //exception class
 {
-    FileError(ULONG errorCode) : win32Error(errorCode) {}
-    ULONG win32Error;
+    NtFileError(NTSTATUS errorCode) : ntError(errorCode) {}
+    NTSTATUS ntError;
 };
 
 
@@ -91,8 +93,8 @@ bool findplus::initDllBinding() //evaluate in ::DllMain() when attaching process
     //http://msdn.microsoft.com/en-us/library/ff563638(v=VS.85).aspx
 
     //verify dynamic dll binding
-    return ntOpenFile &&
-           ntClose    &&
+    return ntOpenFile            &&
+           ntClose               &&
            ntQueryDirectoryFile  &&
            rtlNtStatusToDosError &&
            rtlFreeUnicodeString  &&
@@ -108,9 +110,15 @@ public:
     FileSearcher(const wchar_t* dirname); //throw FileError
     ~FileSearcher();
 
-    void readdir(FileInformation& output); //throw FileError
+    void readDir(FileInformation& output) { (this->*readDirFun)(output); } //throw FileError
+
+    bool tryFallbackToDefaultQuery(); //call if readDir() throws STATUS_NOT_SUPPORTED or similar
 
 private:
+    template <class QueryPolicy> void readDirImpl(FileInformation& output); //throw FileError
+    //handle fallback, if retrieving file id is not supported by file system layer
+    void (FileSearcher::*readDirFun)(FileInformation& output);
+
     UNICODE_STRING ntPathName; //it seems hDir implicitly keeps a reference to this, at least ::FindFirstFile() does no cleanup before ::FindClose()!
     HANDLE hDir;
 
@@ -124,9 +132,43 @@ private:
 };
 
 
+namespace
+{
+/*
+Common C-style policy handling directory traversal:
+
+struct QueryPolicy
+{
+	typedef ... RawFileInfo;
+	static const FILE_INFORMATION_CLASS fileInformationClass = ...;
+	static void extractFileId(const RawFileInfo& rawInfo, FileInformation& fileInfo);
+};
+*/
+
+struct DirQueryDefault
+{
+    typedef FILE_BOTH_DIR_INFORMATION RawFileInfo;
+    static const FILE_INFORMATION_CLASS fileInformationClass = FileBothDirectoryInformation;
+    static void extractFileId(const RawFileInfo& rawInfo, FileInformation& fileInfo) { fileInfo.fileId.QuadPart = 0; }
+};
+
+struct DirQueryFileId
+{
+    typedef FILE_ID_BOTH_DIR_INFORMATION RawFileInfo;
+    static const FILE_INFORMATION_CLASS fileInformationClass = FileIdBothDirectoryInformation;
+    static void extractFileId(const RawFileInfo& rawInfo, FileInformation& fileInfo)
+    {
+        fileInfo.fileId.QuadPart = rawInfo.FileId.QuadPart; //may be 0 even in this context, e.g. for mapped FTP drive!
+        static_assert(sizeof(fileInfo.fileId) == sizeof(rawInfo.FileId), "dang!");
+    }
+};
+}
+
+
 FileSearcher::FileSearcher(const wchar_t* dirname) :
     hDir(NULL),
-    nextEntryOffset(0)
+    nextEntryOffset(0),
+    readDirFun(&FileSearcher::readDirImpl<DirQueryFileId>) //start optimistically
 {
     ntPathName.Buffer = NULL;
     ntPathName.Length = 0;
@@ -136,7 +178,8 @@ FileSearcher::FileSearcher(const wchar_t* dirname) :
     //--------------------------------------------------------------------------------------------------------------
 
     //convert dosFileName, e.g. C:\Users or \\?\C:\Users to ntFileName \??\C:\Users
-    //in contrast to ::FindFirstFile() we don't evaluate the relativeName, however tests indicate ntFileName is *always* filled with an absolute name, even if dosFileName is relative
+    //in contrast to ::FindFirstFile() implementation we don't evaluate the relativeName,
+    //however tests indicate ntFileName is *always* filled with an absolute name, even if dosFileName is relative
 
     //NOTE: RtlDosPathNameToNtPathName_U may be used on all XP/Win7/Win8 for compatibility
     //		RtlDosPathNameToNtPathName_U:         used by Windows XP          available with OS version 3.51 (Windows NT) and higher
@@ -145,7 +188,7 @@ FileSearcher::FileSearcher(const wchar_t* dirname) :
                                       &ntPathName, //__out ntFileName,
                                       NULL,        //__out_optFilePart,
                                       NULL))       //__out_opt relativeName - empty if dosFileName is absolute
-        throw FileError(rtlNtStatusToDosError(STATUS_OBJECT_PATH_NOT_FOUND)); //translates to ERROR_PATH_NOT_FOUND, same behavior like ::FindFirstFileEx()
+        throw NtFileError(STATUS_OBJECT_PATH_NOT_FOUND); //translates to ERROR_PATH_NOT_FOUND, same behavior like ::FindFirstFileEx()
 
     OBJECT_ATTRIBUTES objAttr = {};
     InitializeObjectAttributes(&objAttr,    //[out]           POBJECT_ATTRIBUTES initializedAttributes,
@@ -163,7 +206,7 @@ FileSearcher::FileSearcher(const wchar_t* dirname) :
                                  FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, //__in ULONG shareAccess, - 7 on Win7/Win8, 3 on XP
                                  FILE_DIRECTORY_FILE | FILE_SYNCHRONOUS_IO_NONALERT | FILE_OPEN_FOR_BACKUP_INTENT); //__in ULONG openOptions - 4021 used on all XP/Win7/Win8
         if (!NT_SUCCESS(rv))
-            throw FileError(rtlNtStatusToDosError(rv));
+            throw NtFileError(rv);
     }
 
     guardConstructor.dismiss();
@@ -179,16 +222,33 @@ FileSearcher::~FileSearcher()
 
     if (ntPathName.Buffer)
         rtlFreeUnicodeString(&ntPathName); //cleanup identical to ::FindFirstFile()
-    //note that most if this function seems inlined by the linker, so that its assembly looks equivalent to "RtlFreeHeap(GetProcessHeap(), 0, ntPathName.Buffer)"
+    //note that most of this function seems inlined by the linker, so that its assembly looks equivalent to "RtlFreeHeap(GetProcessHeap(), 0, ntPathName.Buffer)"
+}
+
+
+inline
+bool FileSearcher::tryFallbackToDefaultQuery()
+{
+    if (readDirFun == &FileSearcher::readDirImpl<DirQueryDefault>)
+        return false; //already default
+
+    //Note: NtQueryDirectoryFile() may not respect "restartScan" for some weird Win2000 file system drivers, so we won't bother
+    //Samba before v3.0.22 (Mar 30, 2006) seems to have a bug which sucessfully returns 128 elements via NtQueryDirectoryFile()
+    //and FileIdBothDirectoryInformation, then fails with STATUS_INVALID_LEVEL.
+    //Although traversal is NOT finished yet, it will further return STATUS_NO_MORE_FILES, even if falling back to FileBothDirectoryInformation!!!
+
+    readDirFun = &FileSearcher::readDirImpl<DirQueryDefault>;
+    return true;
 }
 
 
-void FileSearcher::readdir(FileInformation& output)
+template <class QueryPolicy>
+void FileSearcher::readDirImpl(FileInformation& output) //throw FileError
 {
     //although FILE_ID_FULL_DIR_INFORMATION should suffice for our purposes, there are problems on Windows XP for certain directories, e.g. "\\Vboxsvr\build"
     //making NtQueryDirectoryFile() return with STATUS_INVALID_PARAMETER while other directories, e.g. "C:\" work fine for some reason
     //FILE_ID_BOTH_DIR_INFORMATION on the other hand works on XP/Win7/Win8
-    //performance: there is no noticable difference between FILE_ID_BOTH_DIR_INFORMATION and FILE_ID_FULL_DIR_INFORMATION
+    //performance: there is no noticeable difference between FILE_ID_BOTH_DIR_INFORMATION and FILE_ID_FULL_DIR_INFORMATION
 
     /* corresponding first access in ::FindFirstFileW()
 
@@ -216,18 +276,26 @@ void FileSearcher::readdir(FileInformation& output)
                                            &status,     //__out PIO_STATUS_BLOCK ioStatusBlock,
                                            &buffer,     //__out_bcount(Length) PVOID fileInformation,
                                            BUFFER_SIZE, //__in ULONG length, ::FindNextFileW() on all XP/Win7/Win8 uses sizeof(FILE_BOTH_DIR_INFORMATION) + sizeof(TCHAR) * 2000 == 0x1000
-                                           FileIdBothDirectoryInformation, //__in FILE_INFORMATION_CLASS fileInformationClass - all XP/Win7/Win8 use "FileBothDirectoryInformation"
+                                           QueryPolicy::fileInformationClass, //__in FILE_INFORMATION_CLASS fileInformationClass - all XP/Win7/Win8 use "FileBothDirectoryInformation"
                                            false,       //__in BOOLEAN returnSingleEntry,
                                            NULL,        //__in_opt PUNICODE_STRING mask,
                                            false);      //__in BOOLEAN restartScan
         if (!NT_SUCCESS(rv))
-            throw FileError(rtlNtStatusToDosError(rv)); //throws STATUS_NO_MORE_FILES when finished
+        {
+            if (rv == STATUS_NO_SUCH_FILE) //harmonize ntQueryDirectoryFile() error handling! failure to find a file on first call returns STATUS_NO_SUCH_FILE,
+                rv = STATUS_NO_MORE_FILES; //while on subsequent accesses return STATUS_NO_MORE_FILES
+            //note: not all directories contain "., .." entries! E.g. a drive's root directory or NetDrive + ftp.gnu.org\CRYPTO.README"
+            //-> addon: this is NOT a directory, it looks like on in NetDrive, but it's a file in Opera
+
+            throw NtFileError(rv); //throws STATUS_NO_MORE_FILES when finished
+        }
 
-        if (status.Information == 0)                                        //except for the first call to call ::NtQueryDirectoryFile():
-            throw FileError(rtlNtStatusToDosError(STATUS_BUFFER_OVERFLOW)); //if buffer size is too small, return value is STATUS_SUCCESS and Information == 0 -> we don't expect this!
+        if (status.Information == 0)                   //except for the first call to call ::NtQueryDirectoryFile():
+            throw NtFileError(STATUS_BUFFER_OVERFLOW); //if buffer size is too small, return value is STATUS_SUCCESS and Information == 0 -> we don't expect this!
     }
 
-    const FILE_ID_BOTH_DIR_INFORMATION& dirInfo = *reinterpret_cast<FILE_ID_BOTH_DIR_INFORMATION*>(reinterpret_cast<char*>(buffer) + nextEntryOffset);
+    typedef typename QueryPolicy::RawFileInfo RawFileInfo;
+    const RawFileInfo& dirInfo = *reinterpret_cast<RawFileInfo*>(reinterpret_cast<char*>(buffer) + nextEntryOffset);
 
     if (dirInfo.NextEntryOffset == 0)
         nextEntryOffset = 0; //our offset is relative to the beginning of the buffer
@@ -241,15 +309,16 @@ void FileSearcher::readdir(FileInformation& output)
         return tmp;
     };
 
+    QueryPolicy::extractFileId(dirInfo, output);
+
     output.creationTime      = toFileTime(dirInfo.CreationTime);
     output.lastWriteTime     = toFileTime(dirInfo.LastWriteTime);
     output.fileSize.QuadPart = dirInfo.EndOfFile.QuadPart;
-    output.fileId.QuadPart   = dirInfo.FileId.QuadPart;
     output.fileAttributes    = dirInfo.FileAttributes;
     output.shortNameLength   = dirInfo.FileNameLength / sizeof(TCHAR); //FileNameLength is in bytes!
 
     if (dirInfo.FileNameLength + sizeof(TCHAR) > sizeof(output.shortName)) //this may actually happen if ::NtQueryDirectoryFile() decides to return a
-        throw FileError(rtlNtStatusToDosError(STATUS_BUFFER_OVERFLOW));    //short name of length MAX_PATH + 1, 0-termination is not required!
+        throw NtFileError(STATUS_BUFFER_OVERFLOW);    //short name of length MAX_PATH + 1, 0-termination is not required!
 
     ::memcpy(output.shortName, dirInfo.FileName, dirInfo.FileNameLength);
     output.shortName[output.shortNameLength] = 0; //NOTE: FILE_ID_BOTH_DIR_INFORMATION::FileName in general is NOT 0-terminated! It is on XP/Win7, but NOT on Win8!
@@ -257,7 +326,6 @@ void FileSearcher::readdir(FileInformation& output)
     static_assert(sizeof(output.creationTime)   == sizeof(dirInfo.CreationTime),   "dang!");
     static_assert(sizeof(output.lastWriteTime)  == sizeof(dirInfo.LastWriteTime),  "dang!");
     static_assert(sizeof(output.fileSize)       == sizeof(dirInfo.EndOfFile),      "dang!");
-    static_assert(sizeof(output.fileId)         == sizeof(dirInfo.FileId),         "dang!");
     static_assert(sizeof(output.fileAttributes) == sizeof(dirInfo.FileAttributes), "dang!");
 }
 
@@ -268,10 +336,10 @@ FindHandle findplus::openDir(const wchar_t* dirname)
     {
         return new FileSearcher(dirname); //throw FileError
     }
-    catch (const FileError& err)
+    catch (const NtFileError& e)
     {
-        setWin32Error(err.win32Error);
-        return NULL;
+        setWin32Error(rtlNtStatusToDosError(e.ntError));
+        return nullptr;
     }
 }
 
@@ -280,12 +348,28 @@ bool findplus::readDir(FindHandle hnd, FileInformation& output)
 {
     try
     {
-        hnd->readdir(output); //throw FileError
+        hnd->readDir(output); //throw FileError
         return true;
     }
-    catch (const FileError& err)
+    catch (const NtFileError& e)
     {
-        setWin32Error(err.win32Error);
+        /*
+        fallback to default directory query method, if FileIdBothDirectoryInformation is not properly implemented
+        this is required for NetDrive mounted Webdav, e.g. www.box.net and NT4, 2000 remote drives, et al.
+        */
+        if (e.ntError != STATUS_NO_MORE_FILES)
+            if (e.ntError == STATUS_INVALID_LEVEL            ||
+                e.ntError == STATUS_NOT_SUPPORTED            ||
+                e.ntError == STATUS_INVALID_PARAMETER        ||
+                e.ntError == STATUS_INVALID_NETWORK_RESPONSE ||
+                e.ntError == STATUS_INVALID_INFO_CLASS       ||
+                e.ntError == STATUS_ACCESS_VIOLATION) //FileIdBothDirectoryInformation on XP accessing UDF
+            {
+                if (hnd->tryFallbackToDefaultQuery())
+                    return readDir(hnd, output); //implementation of tryFallbackToDefaultQuery() promises, that we don't land in an endless recursion here!
+            }
+
+        setWin32Error(rtlNtStatusToDosError(e.ntError));
         return false;
     }
 }
@@ -293,6 +377,5 @@ bool findplus::readDir(FindHandle hnd, FileInformation& output)
 
 void findplus::closeDir(FindHandle hnd)
 {
-    if (hnd) //play a little "nice"
-        delete hnd;
+    delete hnd;
 }