Name of a named pipe given handle - c++

I'm trying to find the name of a named pipe given it's handle. I found a solution where the named pipe handle is duplicated using NtDuplicateObject and then the name is extracted using NtQueryObject but it's unstable so that's out of the question.
Currently I'm attempting to do so with GetFinalPathNameByHandle but having no luck. I'm not even sure if it's possible to do this but it was mentioned as a potential solution so I'm going with it. The following is adapted from the example code at:
http://msdn.microsoft.com/en-us/library/windows/desktop/aa364962(v=vs.85).aspx
void __cdecl _tmain(int argc, TCHAR *argv[]){
TCHAR Path[BUFSIZE];
HANDLE pipe;
DWORD dwRet;
printf("\n");
if (argc != 2)
{
printf("ERROR:\tIncorrect number of arguments\n\n");
printf("%s <file_name>\n", argv[0]);
return;
}
pipe = CreateNamedPipe(argv[1], PIPE_ACCESS_INBOUND | PIPE_ACCESS_OUTBOUND, PIPE_WAIT, 1,
1024, 1024, 120 * 1000, NULL);
if (pipe == INVALID_HANDLE_VALUE)
{
printf("Could not open file (error %d\n)", GetLastError());
return;
}
dwRet = GetFinalPathNameByHandle(pipe, Path, BUFSIZE, VOLUME_NAME_NT);
if (dwRet < BUFSIZE)
{
_tprintf(TEXT("\nThe final path is: %s\n"), Path);
}
else printf("\nThe required buffer size is %d.\n", dwRet);
CloseHandle(pipe);}
The command line parameter is "\\\\.\\pipe\\mynamedpipe" or "\\.\pipe\mynamedpipe", I've tried both. The output is garbage but more importantly when debugging with Visual Studio 2013 Express while stepping through the program the path variable is garbage directly after the GetFinalPathNameByHandle call.
By garbage I mean:
Path 0x0036fab4 L"쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌쳌... wchar_t[100]
Console output is:
The final path is: ?????????????????????????????????????????????????????????????????????????????????????????????????????????6?╫☻
So I'm officially stuck. Alternatively and possibly a much better solution would be comparing two named pipe handles to each other to determine if they point to the same named pipe. If there is a way to do that it would solve my problem as well.

To answer my own question here. GetFileInformationByHandleEx does exactly this using FileNameInfo for the FileInformationClass parameter and a handle generated by CreateNamedPipe.

Related

Read the file version of a dll in C: The system cannot find the file specified

I am new in the forum but I have already found a lot of help for my other projects.
I am using Visual Studio 2019 and I have created a .rc file which contains the file version and a few other things. These information are displayed in the Properties window of the my dll correctly.
I have created a function
void PrintVersion(TCHAR* pszFilePath, void (*printFunc)(const char*, ...));
which receives the file path and a pointer to my logger function. Inside that function I want to read the file version and print it to the logger. But my logger returns Error in GetFileVersionInfoSize: The system cannot find the file specified.
My function call does look like this:
TCHAR* filename = L"mydll.dll";
PrintVersion(filename, gPrintFunc);
And the function is implemented as follows:
// Read the version of the dll and write it to the logger
void PrintVersion(TCHAR* pszFilePath, void (*printFunc)(const char*, ...))
{
DWORD dwSize = 0;
DWORD verHandle = 0;
BYTE* pbVersionInfo = NULL;
VS_FIXEDFILEINFO* pFileInfo = NULL;
UINT puLenFileInfo = 0;
// Get the size of the version information. This is done to check if the file is avaialbe
// If the size is zero then a error occured
dwSize = GetFileVersionInfoSize(pszFilePath, &verHandle);
if (dwSize == 0)
{
gPrintFunc("Error in GetFileVersionInfoSize: ");
PrintLastErrorString(gPrintFunc);
return;
}
// Create some memory for the file version info
pbVersionInfo = malloc(dwSize);
// Store the information into pbVersionInfo
#pragma warning(suppress : 6387)
if (!GetFileVersionInfo(pszFilePath, verHandle, dwSize, pbVersionInfo))
{
gPrintFunc("Error in GetFileVersionInfo: ");
PrintLastErrorString(gPrintFunc);
free(pbVersionInfo);
return;
}
// Make the information easier accessable in pFileInfo
#pragma warning(suppress : 6387)
if (!VerQueryValue(pbVersionInfo, TEXT("\\"), (LPVOID*)&pFileInfo, &puLenFileInfo))
{
gPrintFunc("Error in VerQueryValue: ");
PrintLastErrorString(gPrintFunc);
free(pbVersionInfo);
return;
}
// pFileInfo->dwFileVersionMS and pFileInfo->dwFileVersionLS contain the software version
// Major2B.Minor2B.Revision2B.Build2B
gPrintFunc("File Version of %s: %d.%d.%d.%d\n",
pszFilePath,
(pFileInfo->dwFileVersionMS >> 16) & 0xffff,
(pFileInfo->dwFileVersionMS >> 0) & 0xffff,
(pFileInfo->dwFileVersionLS >> 16) & 0xffff,
(pFileInfo->dwFileVersionLS >> 0) & 0xffff
);
// Free up the reserved memory
free(pbVersionInfo);
}
// Used for receiving the last WIN32 error and write it to the logger
void PrintLastErrorString(void (*printFunc)(const char*, ...))
{
// Get the error id of the last error
DWORD iLastError;
iLastError = GetLastError();
//Ask Win32 to give us the string version of that message ID.
//The parameters we pass in, tell Win32 to create the buffer that holds the message for us (because we don't yet know how long the message string will be).
LPSTR messageBuffer = NULL;
size_t size = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, iLastError, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&messageBuffer, 0, NULL);
gPrintFunc("%s\n", messageBuffer);
return;
}
I created that function by combining a few different C++ and C# examples from this forum. I am not familiar with the TCHAR* datatype. I assume that the problem has maybe something to do with the filename string. Further I am not able to print the filename to the logger with the %s format placeholder. In this case only the first letter of the filename is displayed.
One further info. Before I copied that code to the dll. I created a small console application. And in this case it was possible to read the file version of the exe. I also tried to specify the complete path of the dll. The dll and the exe, which uses the dll are in the same directory.
Maybe someone can help me :)
BR
Thank you for your answers.
I changed now the character set to: Use Unicode Character Set and now it works as expected.

FindFirstFile returns INVALID_HANDLE_VALUE when lpFileName is volume

There is a short example:
WIN32_FIND_DATA fd;
HANDLE h = FindFirstFile(L"C:", &fd);
if (h == INVALID_HANDLE_VALUE)
{
wprintf(L"Err = %d\n", GetLastError());
return 1;
}
do {
std::wstring fullPath(fd.cFileName);
wprintf(L"FullPath = %s\n", fullPath.c_str());
} while (FindNextFile(h, &fd));
FindClose(h);
I'm confused since
HANDLE h = FindFirstFile(L"C:", &fd); // OK
HANDLE h = FindFirstFile(L"E:", &fd); // INVALID_HANDLE_VALUE
HANDLE h = FindFirstFile(L"F:", &fd); // INVALID_HANDLE_VALUE
But E and F are real, existing volumes.
I do so because I need all information from the WIN32_FIND_DATA structure which will be passed to the kernel mode.
This question seems to be based on a misunderstanding. You say:
I do not want to examine the files and directories in "E:*", I want to get information about this volume.
and
I need all information from the WIN32_FIND_DATA structure.
Well, the find data information is meaningful for file and directory objects, but not for volume objects.
You'll need to use some other means to obtain volume information. Perhaps GetVolumeInformation, WMI, or maybe something else depending on your needs.
I think you have to put "E:\\*" not only the volume. Or you want to find the volume entry? Also, it is good to clean fd structure memset( &fd, 0, sizeof fd ).
On my machine (Win7 x64) FindFirstFile(L"C:", &fd) returns -1 (C: is system disc), GetLastError() is 2 (i.e. "file not found").
I've checked how FindFirstFile is working. It converts winapi like path to nt path at some stage using RtlDosPathNameToRelativeNtPathName_U and then checks whether PartName is empty or not.
If it's empty it returns mentioned error code.
if it's a mask, it continues and enumerates entries that match: that's why FindFirstFile(L"C:\\*.*", &fd) returns valid handle. Thus if you need to enumerate all files in C: using form C:\\*.*.
In case if you need a volume information use special function GetVolumeInformation.

FILE_NOT_FOUND when trying to open COM port C++

I am trying to open a com port for reading and writing using C++ but I can't seem to pass the first stage of actually opening it. I get an INVALID_HANDLE_VALUE on the handle
with GetLastError FILE_NOT_FOUND. I have searched around the web for a couple of days I'm fresh out of ideas. I have searched through all the questions regarding COM on this website too.
I have scanned through the existing ports (or so I believe) to get the name of the port right.
I also tried combinations of _T("COM1") with the slashes, without the slashes, with colon, without colon and without the _T
I'm using windows 7 on 64 bit machine.
this is the code i got
I'll be glad for any input on this
void SendToCom(char* data, int len)
{
DWORD cbNeeded = 0;
DWORD dwPorts = 0;
EnumPorts(NULL, 1, NULL, 0, &cbNeeded, &dwPorts);
//What will be the return value
BOOL bSuccess = FALSE;
LPCSTR COM1 ;
BYTE* pPorts = static_cast<BYTE*>(malloc(cbNeeded));
bSuccess = EnumPorts(NULL, 1, pPorts, cbNeeded, &cbNeeded, &dwPorts);
if (bSuccess){
PORT_INFO_1* pPortInfo = reinterpret_cast<PORT_INFO_1*>(pPorts);
for (DWORD i=0; i<dwPorts; i++)
{
//If it looks like "COMX" then
size_t nLen = _tcslen(pPortInfo->pName);
if (nLen > 3)
{
if ((_tcsnicmp(pPortInfo->pName, _T("COM"), 3) == 0) ){
COM1 =pPortInfo->pName;
//COM1 ="\\\\.\\COM1";
HANDLE m_hCommPort = CreateFile( COM1 ,
GENERIC_READ|GENERIC_WRITE, // access ( read and write)
0, // (share) 0:cannot share the COM port
NULL, // security (None)
OPEN_EXISTING, // creation : open_existing
FILE_FLAG_OVERLAPPED, // we want overlapped operation
NULL // no templates file for COM port...
);
if (m_hCommPort==INVALID_HANDLE_VALUE)
{
DWORD err = GetLastError();
if (err == ERROR_FILE_NOT_FOUND) {
MessageBox(hWnd,"ERROR_FILE_NOT_FOUND",NULL,MB_ABORTRETRYIGNORE);
}
else
if(err == ERROR_INVALID_NAME) {
MessageBox(hWnd,"ERROR_INVALID_NAME",NULL,MB_ABORTRETRYIGNORE);
}
else
{
MessageBox(hWnd,"unkown error",NULL,MB_ABORTRETRYIGNORE);
}
}
else{
WriteAndReadPort(m_hCommPort,data);
}
}
pPortInfo++;
}
}
}
}
The Solution is to use
The Problem is, if your port is Bigger then 9 then you have to use the Syntax
LPCWSTR szPortName = L"\\\\.\\COM11";.
If you are on Windows 10 - running all system updates might help !
I had the same issue that opening port "COM4" returned an error ERROR_FILE_NOT_FOUND. When running the program as "Administrator" it worked. Now after a updating to 1511 the program can open "COM4" even not running as "Administrator".
http://www.cplusplus.com/forum/windows/163855/
Use CreateFileA(...) instead of CreateFile(...)
ERROR_FILE_NOT_FOUND can be produced from CreateFile(L"\\\\.\\COM1", ...) and CreateFile(L"COM1:", ...) after using the Device Manager to change the assigned COM Port number. Disabling and re-enabling the device, or unplugging and reconnecting the USB adapter resolves the issue.
A useful test to confirm whether it is your program or the system is to send data to the port in command prompt. A successful test will show an empty line. A failed test will show an error message.
C:\drop>echo > \\.\COM1
The system cannot find the file specified.
C:\drop>echo > \\.\COM1
C:\drop>

FindFirstFile Issues can't get any example to work.

I keep having issues with the FindFirstFile and FindNextFile I need to get them to list all dlls into an array but I cant get it to list any files. I have tried using and editing the example code from MSDN but that doesn't work either they pass the wrong type of variable to a function. The code I have now is below sorry if it's a mess but I am trying everything to get it to work. I was also using argv[1] because I believe that gives the directory of the .exe which is what I need because that were the dlls will be stored. I am completely confused by why all the examples I try don't work and why I can't amend them to work.
WIN32_FIND_DATA FindFileData;
HANDLE hFind = INVALID_HANDLE_VALUE;
string directorySearch = "E:\\My Documents\\Visual Studio 2010\\Projects\\SEP-Asignment-One\\Debug\\*";
// Find the first file in the directory.
hFind = FindFirstFile(LPCWSTR("E:\\My Documents\\Visual Studio 2010\\Projects\\SEP-Asignment-One\\Debug\\*"), &FindFileData);
if (hFind == INVALID_HANDLE_VALUE)
{
printf ("Invalid file handle. Error is %u.\n", GetLastError());
}
else
{
printf ("First file name is %s.\n", FindFileData.cFileName);
// List all the other files in the directory.
while (FindNextFile(hFind, &FindFileData) != 0)
{
printf ("Next file name is %s.\n", FindFileData.cFileName);
}
FindClose(hFind);
Any Help would be apreceated.
Use std::wstring, wide string literals like L"Hello", and remember to defined UNICODE before including <windows.h> (but that's done by default in a Visual Studio project).
Instead of
hFind = FindFirstFile(LPCWSTR("...")...,
try
hFind = FindFirstFile(_T("...")

Creating a ZIP file on Windows (XP/2003) in C/C++

I am looking for a way to create a ZIP file from a folder in Windows C/C++ APIs. I can find the way to do this in VBScript using the Shell32.Application CopyHere method, and I found a tutorial explaining how to do it in C# also, but nothing for the C API (C++ is fine too, project already uses MFC).
I'd be really grateful if anyone can share some sample C code that can successfully create a zip file on Windows XP/2003. Failing that, if someone can find solid docs or a tutorial that would be great, since MSDN searches don't turn up much. I'm really hoping to avoid having to ship a third-party lib for this, because the functionality is obviously there, I just can't figure out how to access it. Google searches turn up nothing useful, just tantalizing bits and pieces of information. Here's hoping someone in the community has sorted this out and can share it for posterity!
As noted elsewhere in the comments, this will only work on a already-created Zip file. The content must also not already exist in the zip file, or an error will be displayed. Here is the working sample code I was able to create based on the accepted answer. You need to link to shell32.lib and also kernel32.lib (for CreateToolhelp32Snapshot).
#include <windows.h>
#include <shldisp.h>
#include <tlhelp32.h>
#include <stdio.h>
int main(int argc, TCHAR* argv[])
{
DWORD strlen = 0;
char szFrom[] = "C:\\Temp",
szTo[] = "C:\\Sample.zip";
HRESULT hResult;
IShellDispatch *pISD;
Folder *pToFolder = NULL;
VARIANT vDir, vFile, vOpt;
BSTR strptr1, strptr2;
CoInitialize(NULL);
hResult = CoCreateInstance(CLSID_Shell, NULL, CLSCTX_INPROC_SERVER, IID_IShellDispatch, (void **)&pISD);
if (SUCCEEDED(hResult) && pISD != NULL)
{
strlen = MultiByteToWideChar(CP_ACP, 0, szTo, -1, 0, 0);
strptr1 = SysAllocStringLen(0, strlen);
MultiByteToWideChar(CP_ACP, 0, szTo, -1, strptr1, strlen);
VariantInit(&vDir);
vDir.vt = VT_BSTR;
vDir.bstrVal = strptr1;
hResult = pISD->NameSpace(vDir, &pToFolder);
if (SUCCEEDED(hResult))
{
strlen = MultiByteToWideChar(CP_ACP, 0, szFrom, -1, 0, 0);
strptr2 = SysAllocStringLen(0, strlen);
MultiByteToWideChar(CP_ACP, 0, szFrom, -1, strptr2, strlen);
VariantInit(&vFile);
vFile.vt = VT_BSTR;
vFile.bstrVal = strptr2;
VariantInit(&vOpt);
vOpt.vt = VT_I4;
vOpt.lVal = 4; // Do not display a progress dialog box
hResult = NULL;
printf("Copying %s to %s ...\n", szFrom, szTo);
hResult = pToFolder->CopyHere(vFile, vOpt); //NOTE: this appears to always return S_OK even on error
/*
* 1) Enumerate current threads in the process using Thread32First/Thread32Next
* 2) Start the operation
* 3) Enumerate the threads again
* 4) Wait for any new threads using WaitForMultipleObjects
*
* Of course, if the operation creates any new threads that don't exit, then you have a problem.
*/
if (hResult == S_OK) {
//NOTE: hard-coded for testing - be sure not to overflow the array if > 5 threads exist
HANDLE hThrd[5];
HANDLE h = CreateToolhelp32Snapshot(TH32CS_SNAPALL ,0); //TH32CS_SNAPMODULE, 0);
DWORD NUM_THREADS = 0;
if (h != INVALID_HANDLE_VALUE) {
THREADENTRY32 te;
te.dwSize = sizeof(te);
if (Thread32First(h, &te)) {
do {
if (te.dwSize >= (FIELD_OFFSET(THREADENTRY32, th32OwnerProcessID) + sizeof(te.th32OwnerProcessID)) ) {
//only enumerate threads that are called by this process and not the main thread
if((te.th32OwnerProcessID == GetCurrentProcessId()) && (te.th32ThreadID != GetCurrentThreadId()) ){
//printf("Process 0x%04x Thread 0x%04x\n", te.th32OwnerProcessID, te.th32ThreadID);
hThrd[NUM_THREADS] = OpenThread(THREAD_ALL_ACCESS, FALSE, te.th32ThreadID);
NUM_THREADS++;
}
}
te.dwSize = sizeof(te);
} while (Thread32Next(h, &te));
}
CloseHandle(h);
printf("waiting for all threads to exit...\n");
//Wait for all threads to exit
WaitForMultipleObjects(NUM_THREADS, hThrd , TRUE , INFINITE);
//Close All handles
for ( DWORD i = 0; i < NUM_THREADS ; i++ ){
CloseHandle( hThrd[i] );
}
} //if invalid handle
} //if CopyHere() hResult is S_OK
SysFreeString(strptr2);
pToFolder->Release();
}
SysFreeString(strptr1);
pISD->Release();
}
CoUninitialize();
printf ("Press ENTER to exit\n");
getchar();
return 0;
}
I have decided not to go this route despite getting semi-functional code, since after further investigation, it appears the Folder::CopyHere() method does not actually respect the vOptions passed to it, which means you cannot force it to overwrite files or not display error dialogs to the user.
In light of that, I tried the XZip library mentioned by another poster as well. This library functions fine for creating a Zip archive, but note that the ZipAdd() function called with ZIP_FOLDER is not recursive - it merely creates a folder in the archive. In order to recursively zip an archive you will need to use the AddFolderContent() function. For example, to create a C:\Sample.zip and Add the C:\Temp folder to it, use the following:
HZIP newZip = CreateZip("C:\\Sample.zip", NULL, ZIP_FILENAME);
BOOL retval = AddFolderContent(newZip, "C:", "temp");
Important note: the AddFolderContent() function is not functional as included in the XZip library. It will recurse into the directory structure but fails to add any files to the zip archive, due to a bug in the paths passed to ZipAdd(). In order to use this function you'll need to edit the source and change this line:
if (ZipAdd(hZip, RelativePathNewFileFound, RelativePathNewFileFound, 0, ZIP_FILENAME) != ZR_OK)
To the following:
ZRESULT ret;
TCHAR real_path[MAX_PATH] = {0};
_tcscat(real_path, AbsolutePath);
_tcscat(real_path, RelativePathNewFileFound);
if (ZipAdd(hZip, RelativePathNewFileFound, real_path, 0, ZIP_FILENAME) != ZR_OK)
We use XZip for this purpose. It's free, comes as C++ source code and works nicely.
http://www.codeproject.com/KB/cpp/xzipunzip.aspx
EDIT: This answer is old, but I cannot delete it because it was accepted. See the next one
https://stackoverflow.com/a/121720/3937
----- ORIGINAL ANSWER -----
There is sample code to do that here
[EDIT: Link is now broken]
http://www.eggheadcafe.com/software/aspnet/31056644/using-shfileoperation-to.aspx
Make sure you read about how to handle monitoring for the thread to complete.
Edit: From the comments, this code only works on existing zip file, but #Simon provided this code to create a blank zip file
FILE* f = fopen("path", "wb");
fwrite("\x50\x4B\x05\x06\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 22, 1, f);
fclose(f);
The above code to create an empty zip file is broken, as the comments state, but I was able to get it to work. I opened an empty zip in a hex editor, and noted a few differences. Here is my modified example:
FILE* f = fopen("path", "wb");
fwrite("\x50\x4B\x05\x06\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 22, 1, f);
fclose(f);
This worked for me. I was able to then open the compressed folder. Not tested with 3rd party apps such as winzip.
A quick Google search came up with this site: http://www.example-code.com/vcpp/vcUnzip.asp which has a very short example to unzip a file using a downloadable library. There are plenty of other libraries available. Another example is availaible on Code Project entitled Zip and Unzip in the MFC way which has an entire gui example. If you want to do it with .NET then there is always the classes under System.Compression.
There is also the 7-Zip libarary http://www.7-zip.org/sdk.html. This includes source for several languages, and examples.
I do not think that MFC or the Windows standard C/C++ APIs provide an interface to the built in zip functionality.
You could always statically link to the freeware zip library if you don't want to ship another library...