From 669df123648aaa6aeccc70206b5417bc48b4e9ae Mon Sep 17 00:00:00 2001
From: Daniel Wilhelm <daniel@wili.li>
Date: Fri, 18 Apr 2014 17:26:50 +0200
Subject: 5.19

---
 zen/FindFilePlus/find_file_plus.cpp | 38 +++++++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 14 deletions(-)

(limited to 'zen/FindFilePlus/find_file_plus.cpp')

diff --git a/zen/FindFilePlus/find_file_plus.cpp b/zen/FindFilePlus/find_file_plus.cpp
index fdabc46f..ea58005e 100644
--- a/zen/FindFilePlus/find_file_plus.cpp
+++ b/zen/FindFilePlus/find_file_plus.cpp
@@ -113,10 +113,10 @@ public:
     FileSearcher(const wchar_t* dirname); //throw NtFileError
     ~FileSearcher();
 
-    void readDir(FileInformation& output); //throw NtFileError
+    bool readDir(FileInformation& output); //throw NtFileError; returns false if "no more files"
 
 private:
-    template <class QueryPolicy> void readDirImpl(FileInformation& output); //throw NtFileError
+    template <class QueryPolicy> bool readDirImpl(FileInformation& output); //throw NtFileError
 
     UNICODE_STRING dirnameNt; //it seems hDir implicitly keeps a reference to this, at least ::FindFirstFile() does no cleanup before ::FindClose()!
     HANDLE hDir;
@@ -271,11 +271,11 @@ struct DirQueryFileId
 
 
 inline
-void FileSearcher::readDir(FileInformation& output) { readDirImpl<DirQueryFileId>(output); } //throw NtFileError
+bool FileSearcher::readDir(FileInformation& output) { return readDirImpl<DirQueryFileId>(output); } //throw NtFileError
 
 
 template <class QueryPolicy>
-void FileSearcher::readDirImpl(FileInformation& output) //throw NtFileError
+bool FileSearcher::readDirImpl(FileInformation& output) //throw NtFileError; returns false if "no more files"
 {
     //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
@@ -337,25 +337,30 @@ void FileSearcher::readDirImpl(FileInformation& output) //throw NtFileError
             STATUS_NO_SUCH_FILE is abused by some citrix shares instead of "STATUS_INVALID_PARAMETER" so we treat it as such!
             => since the directory is "truly empty" a fallback won't hurt
             */
-            if (rv == STATUS_INVALID_LEVEL            ||
-                rv == STATUS_NOT_SUPPORTED            ||
+            if (rv == STATUS_NO_MORE_FILES) //perf: don't throw an exception in this common case! => 8% perf boost for FFS comparison phase!
+                return false;
+
+            if (rv == STATUS_NOT_SUPPORTED            ||
+                rv == STATUS_INVALID_LEVEL            ||
+                rv == STATUS_NO_SUCH_FILE             || //[!]
                 rv == STATUS_UNEXPECTED_NETWORK_ERROR ||
                 rv == STATUS_INVALID_PARAMETER        ||
                 rv == STATUS_INVALID_NETWORK_RESPONSE ||
                 rv == STATUS_INVALID_INFO_CLASS       ||
+                //rv == STATUS_NOT_IMPLEMENTED          || -> first confirm that these codes
+                //rv == STATUS_INVALID_DEVICE_REQUEST   || -> are in fact used!
                 rv == STATUS_UNSUCCESSFUL             ||
-                rv == STATUS_ACCESS_VIOLATION         ||
-                rv == STATUS_NO_SUCH_FILE) //[!]
+                rv == STATUS_ACCESS_VIOLATION)
                 rv = STATUS_NOT_SUPPORTED;
 
             throw NtFileError(rv); //throws STATUS_NO_MORE_FILES when finished
         }
 
-        //for (NTSTATUS i = 0xC0000000L; i != -1; ++i)
-        //{
-        //    if (rtlNtStatusToDosError(i) == 59) //ERROR_UNEXP_NET_ERR
-        //        __asm int 3;
-        //}
+        //  for (NTSTATUS i = 0xC0000000L; i != -1; ++i)
+        //  {
+        //      if (rtlNtStatusToDosError(i) == 59) //ERROR_UNEXP_NET_ERR
+        //		    __debugbreak(); //__asm int 3;
+        //	}
 
         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!
@@ -399,6 +404,7 @@ void FileSearcher::readDirImpl(FileInformation& output) //throw NtFileError
     static_assert(sizeof(output.lastWriteTime)  == sizeof(dirInfo.LastWriteTime),  "dang!");
     static_assert(sizeof(output.fileSize)       == sizeof(dirInfo.EndOfFile),      "dang!");
     static_assert(sizeof(output.fileAttributes) == sizeof(dirInfo.FileAttributes), "dang!");
+    return true;
 }
 
 
@@ -425,7 +431,11 @@ bool findplus::readDir(FindHandle hnd, FileInformation& output)
 {
     try
     {
-        hnd->readDir(output); //throw NtFileError
+        if (!hnd->readDir(output)) //throw NtFileError
+        {
+            setWin32Error(rtlNtStatusToDosError(STATUS_NO_MORE_FILES));
+            return false;
+        }
         return true;
     }
     catch (const NtFileError& e)
-- 
cgit