4.6

2 files changed, 61 insertions, 81 deletions

diff --git a/zen/FindFilePlus/find_file_plus.cpp b/zen/FindFilePlus/find_file_plus.cpp
index e613177b..876d0c0f 100644
--- a/zen/FindFilePlus/find_file_plus.cpp
+++ b/zen/FindFilePlus/find_file_plus.cpp
@@ -110,16 +110,12 @@ public:
     FileSearcher(const wchar_t* dirname); //throw FileError
     ~FileSearcher();
 
-    void readDir(FileInformation& output) { (this->*readDirFun)(output); } //throw FileError
-
-    bool tryFallbackToDefaultQuery(); //call if readDir() throws STATUS_NOT_SUPPORTED or similar
+    void readDir(FileInformation& output); //throw FileError
 
 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()!
+    UNICODE_STRING dirnameNt; //it seems hDir implicitly keeps a reference to this, at least ::FindFirstFile() does no cleanup before ::FindClose()!
     HANDLE hDir;
 
     ULONG  nextEntryOffset; //!= 0 if entry is waiting in buffer
@@ -132,47 +128,13 @@ 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),
-    readDirFun(&FileSearcher::readDirImpl<DirQueryFileId>) //start optimistically
+    nextEntryOffset(0)
 {
-    ntPathName.Buffer = NULL;
-    ntPathName.Length = 0;
-    ntPathName.MaximumLength = 0;
+    dirnameNt.Buffer        = NULL;
+    dirnameNt.Length        = 0;
+    dirnameNt.MaximumLength = 0;
 
     zen::ScopeGuard guardConstructor = zen::makeGuard([&]() { this->~FileSearcher(); });
     //--------------------------------------------------------------------------------------------------------------
@@ -184,19 +146,19 @@ FileSearcher::FileSearcher(const wchar_t* dirname) :
     //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
     //		RtlDosPathNameToRelativeNtPathName_U: used by Win7/Win8           available with OS version 5.2  (Windows Server 2003) and higher
-    if (!rtlDosPathNameToNtPathName_U(dirname,     //__in dosFileName,
-                                      &ntPathName, //__out ntFileName,
-                                      NULL,        //__out_optFilePart,
-                                      NULL))       //__out_opt relativeName - empty if dosFileName is absolute
+    if (!rtlDosPathNameToNtPathName_U(dirname,    //__in dosFileName,
+                                      &dirnameNt, //__out ntFileName,
+                                      NULL,       //__out_optFilePart,
+                                      NULL))      //__out_opt relativeName - empty if dosFileName is absolute
         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,
-                               &ntPathName, //[in]            PUNICODE_STRING objectName,
+                               &dirnameNt,  //[in]            PUNICODE_STRING objectName,
                                OBJ_CASE_INSENSITIVE, //[in]   ULONG attributes,
                                NULL,        //[in]            HANDLE rootDirectory,
                                NULL);       //[in, optional]  PSECURITY_DESCRIPTOR securityDescriptor
-
     {
         IO_STATUS_BLOCK status = {};
         NTSTATUS rv = ntOpenFile(&hDir,                        //__out PHANDLE FileHandle,
@@ -220,28 +182,49 @@ FileSearcher::~FileSearcher()
     if (hDir)
         ntClose(hDir);
 
-    if (ntPathName.Buffer)
-        rtlFreeUnicodeString(&ntPathName); //cleanup identical to ::FindFirstFile()
+    if (dirnameNt.Buffer)
+        rtlFreeUnicodeString(&dirnameNt); //cleanup identical to ::FindFirstFile()
     //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()
+namespace
 {
-    if (readDirFun == &FileSearcher::readDirImpl<DirQueryDefault>)
-        return false; //already default
+/*
+Common C-style policy handling directory traversal:
 
-    //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!!!
+struct QueryPolicy
+{
+	typedef ... RawFileInfo;
+	static const FILE_INFORMATION_CLASS fileInformationClass = ...;
+	static void extractFileId(const RawFileInfo& rawInfo, FileInformation& fileInfo);
+};
+*/
 
-    readDirFun = &FileSearcher::readDirImpl<DirQueryDefault>;
-    return true;
+struct DirQueryDefault //as implemented in Win32 FindFirstFile()/FindNextFile()
+{
+    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!");
+    }
+};
 }
 
 
+inline
+void FileSearcher::readDir(FileInformation& output) { readDirImpl<DirQueryFileId>(output); } //throw FileError
+
+
 template <class QueryPolicy>
 void FileSearcher::readDirImpl(FileInformation& output) //throw FileError
 {
@@ -283,9 +266,9 @@ void FileSearcher::readDirImpl(FileInformation& output) //throw FileError
         if (!NT_SUCCESS(rv))
         {
             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
+                rv = STATUS_NO_MORE_FILES; //while on subsequent accesses returns 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
+            //-> addon: this is NOT a directory, it looks like one in NetDrive, but it's a file in Opera
 
             throw NtFileError(rv); //throws STATUS_NO_MORE_FILES when finished
         }
@@ -353,22 +336,6 @@ bool findplus::readDir(FindHandle hnd, FileInformation& output)
     }
     catch (const NtFileError& e)
     {
-        /*
-        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;
     }
diff --git a/zen/FindFilePlus/find_file_plus.h b/zen/FindFilePlus/find_file_plus.h
index 33e9a178..2ef5affe 100644
--- a/zen/FindFilePlus/find_file_plus.h
+++ b/zen/FindFilePlus/find_file_plus.h
@@ -38,7 +38,7 @@ struct FileInformation
     DWORD fileAttributes;
     DWORD shortNameLength;
     WCHAR shortName[MAX_PATH + 1]; //shortName is 0-terminated
-}; //no need for #pragma pack -> all members already starting at 4 byte boundary!
+}; //no need for #pragma pack -> all members are perfectly 4, 8 byte aligned!
 
 class FileSearcher;
 typedef FileSearcher* FindHandle;
@@ -49,6 +49,19 @@ FindHandle openDir(const wchar_t* dirname); //returns NULL on error, call ::GetL
 
 DLL_FUNCTION_DECLARATION
 bool readDir(FindHandle hnd, FileInformation& output); //returns false on error or if there are no more files; ::GetLastError() returns ERROR_NO_MORE_FILES in this case
+/*
+warning:; this may also return file system implementation dependent error codes like ERROR_NOT_SUPPORTED, ERROR_INVALID_LEVEL,
+ect. if "FileIdBothDirectoryInformation" is not supported! We need a fallback:
+
+    sometimes it's *not* sufficient to use fallback for NtQueryDirectoryFile() alone, we need to reset "hDir", since it may be f$ck$d $p by some poor file system layer implementation:
+    - 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. Fallback to FileBothDirectoryInformation will return STATUS_NO_MORE_FILES, even if there *are* more files
+    - NtQueryDirectoryFile() may *not* respect "restartScan" for some weird Win2000 file system drivers, so we cannot rely on this as a replacement for a "hDir" reset
+    - Windows 7 Remote Desktop sharing does not work unless "hDir" is reset!
+	=> let's assume worst case in general and do a reset!
+	perf note: implementing this reset at a folder level is possible, but a huge perf-killer (additional open/close handle), therefore fallback must apply to a complete folder (sub-)tree!
+	=> caller needs to handle this and implement FindFirstFile()/FindNextFile() fallback!
+*/
 
 DLL_FUNCTION_DECLARATION
 void closeDir(FindHandle hnd);