windows-nt/Source/XPSP1/NT/shell/shell32/treewalk.cpp
2020-09-26 16:20:57 +08:00

533 lines
20 KiB
C++

// This file contains the implementation of CShellTreeWalker, a COM object
// that inherits IShellTreeWalker, and it will recursively enumerate all the
// files (or directories or both) starting from a root directory that match a
// certain spec.
// 1. The tree walker is reparse point aware, it does not traverse into reparse
// point folders by default, but will if specified
// 2. It keeps track of the number of files, directories, depth, and total
// size of all files encountered.
// 3. It will stop the traversal right away if any error message is returned
// from the callback functions except for E_NOTIMPL
// 4. It will jump out of the current working directory if S_FALSE is returned from callback
// functions.
//
// History:
// 12-5-97 by dli
#include "shellprv.h"
#include "validate.h"
#define IS_FILE_DIRECTORY(pwfd) ((pwfd)->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
#define IS_FILE_REPARSE_POINT(pwfd) ((pwfd)->dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)
// Call back flags for _CallCallBack
#define STWCB_FILE 1
#define STWCB_ERROR 2
#define STWCB_ENTERDIR 3
#define STWCB_LEAVEDIR 4
#define TF_TREEWALKER 0
STDAPI_(DWORD) PathGetClusterSize(LPCTSTR pszPath);
class CShellTreeWalker : public IShellTreeWalker
{
public:
CShellTreeWalker();
// IUnknown
STDMETHODIMP QueryInterface(REFIID riid, void ** ppv);
STDMETHODIMP_(ULONG) AddRef(void) ;
STDMETHODIMP_(ULONG) Release(void);
// IShellTreeWalker
STDMETHODIMP WalkTree(DWORD dwFlags, LPCWSTR pwszWalkRoot, LPCWSTR pwszWalkSpec, int iMaxPath, IShellTreeWalkerCallBack * pstwcb);
private:
LONG _cRef;
DWORD _dwFlags; // Flags indicating the search status
UINT _nMaxDepth; // Maximum depth we walk into
UINT _nDepth; // Current depth
UINT _nFiles; // Number of files we have seen so far
UINT _nDirs; // Number of directories we have seen
BOOL _bFolderFirst; // Do the folders first
DWORD _dwClusterSize; // the size of a cluster
ULONGLONG _ulTotalSize; // total size of all files we have seen
ULONGLONG _ulActualSize; // total size on disk, taking into account compression, sparse files, and cluster slop
TCHAR _szWalkBuf[MAX_PATH]; // The path buffer used in the walk
LPCTSTR _pszWalkSpec; // The spec we use in FindFirstFile and FindNextFile
IShellTreeWalkerCallBack * _pstwcb; // The call back interface pointer
WIN32_FIND_DATA _wfd; // The temp storage of WIN32_FIND_DATA
WIN32_FIND_DATA _fdTopLevelFolder; // The top level folder info
HRESULT _CallCallBacks(DWORD dwCallReason, WIN32_FIND_DATA * pwfd);
HRESULT _ProcessAndRecurse(WIN32_FIND_DATA * pwfd);
HRESULT _TreeWalkerHelper();
};
CShellTreeWalker::CShellTreeWalker() : _cRef(1)
{
ASSERT(_dwFlags == 0);
ASSERT(_bFolderFirst == FALSE);
ASSERT(_nMaxDepth == 0);
ASSERT(_nDepth == 0);
ASSERT(_nDirs == 0);
ASSERT(_ulTotalSize == 0);
ASSERT(_ulActualSize == 0);
ASSERT(_pszWalkSpec == NULL);
ASSERT(_pstwcb == NULL);
ASSERT(_szWalkBuf[0] == 0);
}
// _CallCallBack: convert the TCHARs to WCHARs and call the callback functions
HRESULT CShellTreeWalker::_CallCallBacks(DWORD dwReason, WIN32_FIND_DATA * pwfd)
{
HRESULT hr;
WCHAR wszDir[MAX_PATH];
WCHAR wszFileName[MAX_PATH];
#ifndef UNICODE
CHAR szTemp[MAX_PATH];
#endif
WIN32_FIND_DATAW wfdw = {0};
WIN32_FIND_DATAW* pwfdw = NULL;
TREEWALKERSTATS tws = {0};
tws.nFiles = _nFiles;
tws.nFolders = _nDirs;
tws.nDepth = _nDepth;
tws.ulTotalSize = _ulTotalSize;
tws.ulActualSize = _ulActualSize;
tws.dwClusterSize = _dwClusterSize;
// _szWalkBuf to wszDir
#ifdef UNICODE
lstrcpy(wszDir, _szWalkBuf);
lstrcpy(wszFileName, wszDir);
PathCombine(wszFileName, wszFileName, pwfd->cFileName);
#else
SHAnsiToUnicode(_szWalkBuf, wszDir, ARRAYSIZE(wszDir));
lstrcpy(szTemp, _szWalkBuf);
PathCombine(szTemp, szTemp, pwfd->cFileName);
SHAnsiToUnicode(szTemp, wszFileName, ARRAYSIZE(wszFileName));
#endif
if (pwfd && ((dwReason == STWCB_FILE) || (dwReason == STWCB_ENTERDIR)))
{
// WIN32_FIND_DATAA to WIN32_FIND_DATAW
memcpy(&wfdw, pwfd, sizeof(*pwfd));
#ifndef UNICODE
SHAnsiToUnicode(pwfd->cFileName, wfdw.cFileName, ARRAYSIZE(wfdw.cFileName));
SHAnsiToUnicode(pwfd->cAlternateFileName, wfdw.cAlternateFileName, ARRAYSIZE(wfdw.cAlternateFileName));
#endif
pwfdw = &wfdw;
}
switch (dwReason)
{
case STWCB_FILE:
hr = _pstwcb->FoundFile(wszFileName, &tws, pwfdw);
TraceMsg(TF_TREEWALKER, "TreeWalker Callback FoundFile: %s\\%s dwReason: %x nFiles: %d nDepth: %d nDirs: %d",
_szWalkBuf, pwfd->cFileName, dwReason, _nFiles, _nDepth, _nDirs);
break;
case STWCB_ENTERDIR:
hr = _pstwcb->EnterFolder(wszDir, &tws, pwfdw);
TraceMsg(TF_TREEWALKER, "TreeWalker Callback EnterFolder: %s dwReason: %x nFiles: %d nDepth: %d nDirs: %d",
_szWalkBuf, dwReason, _nFiles, _nDepth, _nDirs);
break;
case STWCB_LEAVEDIR:
hr = _pstwcb->LeaveFolder(wszDir, &tws);
break;
// case STWCB_ERROR:
// hr = _pstwcb->HandleError(S_OK, wszDir, &tws);
// break;
default:
hr = S_OK;
break;
}
// Error messages are significant to us, all E_ messages are interpreted as "Stop right now!!"
if (hr == E_NOTIMPL)
hr = S_OK;
return hr;
}
// Call call back funtions on directories and files, recurse on directories if there is no objection
// from the callback object
HRESULT CShellTreeWalker::_ProcessAndRecurse(WIN32_FIND_DATA * pwfd)
{
HRESULT hr = S_OK;
// Don't recurse on reparse points by default
if (IS_FILE_DIRECTORY(pwfd) && (!IS_FILE_REPARSE_POINT(pwfd) || (_dwFlags & WT_GOINTOREPARSEPOINT)))
{
// NTRAID94635 15mar00: If we are in a symbolic link, we need to detect cycles,
// the common prefix method in BeenThereDoneThat will work as long as we
// keep track of all junction point targets we ran into.
// use _szWalkBuf since we dont want any stack variables, because we are a recursive function
if (PathCombine(_szWalkBuf, _szWalkBuf, pwfd->cFileName))
{
// We remember the total number of sub directories we have seen
// doesn't matter if the client approves or not(call back returns S_OK or S_FALSE or E_FAIL)
_nDirs++;
// Let the CallBack object know that we are about to enter a directory
if (_dwFlags & WT_NOTIFYFOLDERENTER)
hr = _CallCallBacks(STWCB_ENTERDIR, pwfd);
if ((hr == S_OK) && (_nDepth < _nMaxDepth))
{
_nDepth++;
hr = _TreeWalkerHelper();
_nDepth--;
}
else if (hr == S_FALSE)
hr = S_OK;
// Let the CallBack object know that we are about to leave a directory
if (_dwFlags & WT_NOTIFYFOLDERLEAVE)
_CallCallBacks(STWCB_LEAVEDIR, NULL);
// Peel off the subdirectory we tagged on in the above PathCombine Ex:"c:\bin\fun --> c:\bin"
PathRemoveFileSpec(_szWalkBuf);
}
}
else
{
// Count the number of files and compute the total size before calling the
// call back object.
ULARGE_INTEGER ulTemp;
_nFiles++;
ulTemp.LowPart = pwfd->nFileSizeLow;
ulTemp.HighPart = pwfd->nFileSizeHigh;
_ulTotalSize += ulTemp.QuadPart;
// when calculating the total size, we need to find out if the file is compressed or sparse (NTFS only case)
if (pwfd->dwFileAttributes & (FILE_ATTRIBUTE_COMPRESSED | FILE_ATTRIBUTE_SPARSE_FILE))
{
// use _szWalkBuf since we dont want any stack variables, because we are a recursive function
PathCombine(_szWalkBuf, _szWalkBuf, pwfd->cFileName);
// eithe the file is compressed or sparse, we need to call GetCompressedFileSize to get the real
// size on disk for this file (NOTE: GetCompressedFileSize takes into account cluster slop, except
// for files < 1 cluster, and we take care of that below)
ulTemp.LowPart = SHGetCompressedFileSize(_szWalkBuf, &ulTemp.HighPart);
_ulActualSize += ulTemp.QuadPart;
// Peel off the filename we tagged on above
PathRemoveFileSpec(_szWalkBuf);
}
else
{
// (reinerf) the cluster size could change if we started on one volume and have now
// walked onto another mounted volume
//
// PathGetClusterSize caches the last request, so this check will be fast in the common case
//
PathCombine(_szWalkBuf, _szWalkBuf, pwfd->cFileName);
_dwClusterSize = PathGetClusterSize(_szWalkBuf);
PathRemoveFileSpec(_szWalkBuf);
// if its not compressed, we just round up to the drive's cluster size. ulTemp was setup
// already for us above, so just round it to the cluster and add it in
_ulActualSize += ROUND_TO_CLUSTER(ulTemp.QuadPart, _dwClusterSize);
}
hr = _CallCallBacks(STWCB_FILE, pwfd);
}
return hr;
}
#define DELAY_ARRAY_GROW 32
// Recursive function that does the real work on the traversal,
HRESULT CShellTreeWalker::_TreeWalkerHelper()
{
HRESULT hr = S_OK;
TraceMsg(TF_TREEWALKER, "TreeWalkerHelper started on: %s flags: %x nFiles: %d nDepth: %d nDirs: %d",
_szWalkBuf, _dwFlags, _nFiles, _nDepth, _nDirs);
// Let the CallBack object know that we are about to start the walk
// provided he cares about the root
if (_nDepth == 0 && !(_dwFlags & WT_EXCLUDEWALKROOT) &&
(_dwFlags & WT_NOTIFYFOLDERENTER))
{
// Get the info for the TopLevelFolder
HANDLE hTopLevelFolder = FindFirstFile(_szWalkBuf, &_fdTopLevelFolder);
if (hTopLevelFolder == INVALID_HANDLE_VALUE)
{
LPTSTR pszFileName;
DWORD dwAttribs = -1; // assume failure
// We could have failed if we tried to do a FindFirstFile on the root (c:\)
// or if something is really wrong, to test for this we do a GetFileAttributes (GetFileAttributesEx on NT)
// on NT we can use GetFileAttributesEx to get both the attribs and part of the win32fd
if (GetFileAttributesEx(_szWalkBuf, GetFileExInfoStandard, (LPVOID)&_fdTopLevelFolder))
{
// success!
dwAttribs = _fdTopLevelFolder.dwFileAttributes;
pszFileName = PathFindFileName(_szWalkBuf);
lstrcpyn(_fdTopLevelFolder.cFileName, pszFileName, ARRAYSIZE(_fdTopLevelFolder.cFileName));
lstrcpyn(_fdTopLevelFolder.cAlternateFileName, pszFileName, ARRAYSIZE(_fdTopLevelFolder.cAlternateFileName));
}
else
{
// fall back to the ole GetFileAttrbutes
dwAttribs = GetFileAttributes(_szWalkBuf);
if (dwAttribs != -1)
{
// success!
// On win95 we steal a bunch of the find data from our first child, and fake the rest.
// Its the best we can do.
memcpy(&_fdTopLevelFolder, &_wfd, sizeof(_fdTopLevelFolder));
_fdTopLevelFolder.dwFileAttributes = dwAttribs;
pszFileName = PathFindFileName(_szWalkBuf);
lstrcpyn(_fdTopLevelFolder.cFileName, pszFileName, ARRAYSIZE(_fdTopLevelFolder.cFileName));
lstrcpyn(_fdTopLevelFolder.cAlternateFileName, pszFileName, ARRAYSIZE(_fdTopLevelFolder.cAlternateFileName));
}
}
if (dwAttribs == -1)
{
// this is very bad, so we bail
TraceMsg(TF_TREEWALKER, "Tree Walker: GetFileAttributes/Ex(%s) failed. Stopping the walk.", _szWalkBuf);
return E_FAIL;
}
}
else
{
// We sucessfully got the find data, good.
FindClose(hTopLevelFolder);
}
// call the callback for the first enterdir
hr = _CallCallBacks(STWCB_ENTERDIR, &_fdTopLevelFolder);
}
// Do the real tree walk here
if (hr == S_OK)
{
// always use *.* to search when we are not at our maximum level because
// we need the sub directories
// PERF: this can be changed on NT by using FindFirstFileEx if WT_FOLDERONLY
LPCTSTR pszSpec = (_pszWalkSpec && (_nDepth == _nMaxDepth)) ? _pszWalkSpec : c_szStarDotStar;
if (PathCombine(_szWalkBuf, _szWalkBuf, pszSpec))
{
HDSA hdsaDelayed = NULL; // array of found items that will be delayed and processed later
HANDLE hFind;
// Start finding the sub folders and files
hFind = FindFirstFile(_szWalkBuf, &_wfd);
// Peel off the find spec Ex:"c:\bin\*.* --> c:\bin"
PathRemoveFileSpec(_szWalkBuf);
if (hFind != INVALID_HANDLE_VALUE)
{
BOOL bDir = FALSE;
do
{
// Skip over the . and .. entries.
if (PathIsDotOrDotDot(_wfd.cFileName))
continue;
bDir = BOOLIFY(IS_FILE_DIRECTORY(&_wfd));
// If this is a file, and we are not interested in files or this file spec does not match the one we were
// looking for.
if ((!bDir) && ((_dwFlags & WT_FOLDERONLY) ||
(_pszWalkSpec && (_nDepth < _nMaxDepth) && !PathMatchSpec(_wfd.cFileName, _pszWalkSpec))))
continue;
// The following EQUAL determines whether we want to process
// the data found or save it in the HDSA array and process them later.
// Enumerate the folder or file now? (determined by the WT_FOLDERFIRST flag)
if (bDir == BOOLIFY(_bFolderFirst))
{
// Yes
hr = _ProcessAndRecurse(&_wfd);
// if hr is failure code someone said "stop right now"
// if hr is S_FALSE some one said "quit this directory and start with next one"
if (hr != S_OK)
break;
}
else
{
// No; enumerate it once we're finished with the opposite.
if (!hdsaDelayed)
hdsaDelayed = DSA_Create(sizeof(WIN32_FIND_DATA), DELAY_ARRAY_GROW);
if (!hdsaDelayed)
{
hr = E_OUTOFMEMORY;
break;
}
DSA_AppendItem(hdsaDelayed, &_wfd);
}
} while (FindNextFile(hFind, &_wfd));
FindClose(hFind);
}
else
{
// find first file failed, this is a good place to report error
DWORD dwErr = GetLastError();
TraceMsg(TF_TREEWALKER, "***WARNING***: FindFirstFile faied on %s%s with error = %d", _szWalkBuf, _pszWalkSpec, dwErr);
}
// Process the delayed items, these are either directories or files
if (hdsaDelayed)
{
// we should have finished everything in the above do while loop in folderonly case
ASSERT(!(_dwFlags & WT_FOLDERONLY));
// if hr is failure code someone said "stop right now"
// if hr is S_FALSE some one said "quit this directory and start with next one"
if (hr == S_OK)
{
int ihdsa;
for (ihdsa = 0; ihdsa < DSA_GetItemCount(hdsaDelayed); ihdsa++)
{
WIN32_FIND_DATA * pwfd = (WIN32_FIND_DATA *)DSA_GetItemPtr(hdsaDelayed, ihdsa);
hr = _ProcessAndRecurse(pwfd);
if (hr != S_OK)
break;
}
}
DSA_Destroy(hdsaDelayed);
}
// Let the CallBack object know that we are finishing the walk
if (_nDepth == 0 && !(_dwFlags & WT_EXCLUDEWALKROOT) &&
(_dwFlags & WT_NOTIFYFOLDERLEAVE) && (S_OK == hr))
hr = _CallCallBacks(STWCB_LEAVEDIR, &_fdTopLevelFolder);
// hr was S_FALSE because someone wanted us to jump out of this current directory
// but don't pass it back to our parent directory
if (hr == S_FALSE)
hr = S_OK;
}
else
TraceMsg(TF_TREEWALKER, "***WARNING***: PathCombine failed!!!!");
}
return hr;
}
// IShellTreeWalker::WalkTree is the main function for the IShellTreeWalker interface
HRESULT CShellTreeWalker::WalkTree(DWORD dwFlags, LPCWSTR pwszWalkRoot, LPCWSTR pwszWalkSpec, int iMaxDepth, IShellTreeWalkerCallBack * pstwcb)
{
HRESULT hr = E_FAIL;
TCHAR szWalkSpec[64];
// must have a call back object to talk to
ASSERT(IS_VALID_CODE_PTR(pstwcb, IShellTreeWalkerCackBack));
if (pstwcb == NULL)
return E_INVALIDARG;
// make sure we have a valid directory to start with
ASSERT(IS_VALID_STRING_PTRW(pwszWalkRoot, -1));
if ((pwszWalkRoot != NULL) && (pwszWalkRoot[0] != L'\0'))
{
SHUnicodeToTChar(pwszWalkRoot, _szWalkBuf, ARRAYSIZE(_szWalkBuf));
// call back
_pstwcb = pstwcb;
// copy the search flags and fix it up
_dwFlags = dwFlags & WT_ALL;
// this will save us from using the hdsa array to hold the directories
if (_dwFlags & WT_FOLDERONLY)
{
_dwFlags |= WT_FOLDERFIRST;
// It will be pretty meanless if the below flags are not set, because
// we don't call FoundFile in the FolderOnly case.
ASSERT(_dwFlags & (WT_NOTIFYFOLDERENTER | WT_NOTIFYFOLDERLEAVE));
}
if (_dwFlags & WT_FOLDERFIRST)
_bFolderFirst = TRUE;
if ((pwszWalkSpec != NULL) && (pwszWalkSpec[0] != L'\0'))
{
SHUnicodeToTChar(pwszWalkSpec, szWalkSpec, ARRAYSIZE(szWalkSpec));
_pszWalkSpec = szWalkSpec;
}
_nMaxDepth = (dwFlags & WT_MAXDEPTH) ? iMaxDepth : 256;
_dwClusterSize = PathGetClusterSize(_szWalkBuf);
hr = _TreeWalkerHelper();
}
else
TraceMsg(TF_WARNING, "CShellTreeWalker::WalkTree Failed! due to bad _szWalkBuf");
return hr;
}
// IShellTreeWalker::QueryInterface
HRESULT CShellTreeWalker::QueryInterface(REFIID riid, void ** ppv)
{
static const QITAB qit[] = {
QITABENT(CShellTreeWalker, IShellTreeWalker),
{ 0 },
};
return QISearch(this, qit, riid, ppv);
}
// IShellTreeWalker::AddRef
ULONG CShellTreeWalker::AddRef()
{
return InterlockedIncrement(&_cRef);
}
// IShellTreeWalker::Release
ULONG CShellTreeWalker::Release()
{
if (InterlockedDecrement(&_cRef))
return _cRef;
delete this;
return 0;
}
STDAPI CShellTreeWalker_CreateInstance(IUnknown* pUnkOuter, REFIID riid, OUT void **ppvOut)
{
HRESULT hr;
*ppvOut = NULL;
CShellTreeWalker *pstw = new CShellTreeWalker;
if (!pstw)
return E_OUTOFMEMORY;
hr = pstw->QueryInterface(riid, ppvOut);
pstw->Release();
return hr;
}