windows-nt/Source/XPSP1/NT/admin/wmi/wbem/winmgmt/a51/filecach.cpp

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2020-09-26 03:20:57 -05:00
/*++
Copyright (C) 2000-2001 Microsoft Corporation
--*/
#include <windows.h>
#include <wbemcomn.h>
#include "filecach.h"
long CFileCache::Initialize(LPCWSTR wszBaseName)
{
long lRes;
wcscpy(m_wszBaseName, wszBaseName);
wcscat(m_wszBaseName, L"\\");
m_dwBaseNameLen = wcslen(m_wszBaseName);
//
// Read the maximum stage-file size from the registry
//
HKEY hKey;
lRes = RegOpenKeyExW(HKEY_LOCAL_MACHINE,
L"SOFTWARE\\Microsoft\\WBEM\\CIMOM",
0, KEY_READ | KEY_WRITE, &hKey);
if(lRes)
return lRes;
CRegCloseMe cm(hKey);
DWORD dwLen = sizeof(DWORD);
DWORD dwMaxLen;
lRes = RegQueryValueExW(hKey, L"Max Stage File Size", NULL, NULL,
(LPBYTE)&dwMaxLen, &dwLen);
//
// If not there, set to default and write the default into the registry
//
if(lRes != ERROR_SUCCESS)
{
dwMaxLen = 5000000;
lRes = RegSetValueExW(hKey, L"Max Stage File Size", 0, REG_DWORD,
(LPBYTE)&dwMaxLen, sizeof(DWORD));
}
dwLen = sizeof(DWORD);
DWORD dwAbortTransactionLen;
lRes = RegQueryValueExW(hKey, L"Absolute Max Stage File Size", NULL, NULL,
(LPBYTE)&dwAbortTransactionLen, &dwLen);
//
// If not there, set to default and write the default into the registry
//
if(lRes != ERROR_SUCCESS || dwAbortTransactionLen == dwMaxLen * 10)
{
dwAbortTransactionLen = 0x7FFFFFFF;
lRes = RegSetValueExW(hKey, L"Absolute Max Stage File Size", 0,
REG_DWORD, (LPBYTE)&dwAbortTransactionLen, sizeof(DWORD));
}
if(dwMaxLen == 0)
{
//
// Staged writes are disabled!
//
m_pMainStage = NULL;
}
else
{
//
// Create the main staging area
//
CFileName wszStagingName;
if (wszStagingName == NULL)
return ERROR_OUTOFMEMORY;
swprintf(wszStagingName, L"%s\\MainStage.dat", wszBaseName);
m_pMainStage = new CExecutableStagingFile(this, m_wszBaseName,
dwMaxLen, dwAbortTransactionLen);
/*
m_pMainStage = new CPermanentStagingFile(this, m_wszBaseName);
*/
if(m_pMainStage == NULL)
return E_OUTOFMEMORY;
long lRes = m_pMainStage->Create(wszStagingName);
if(lRes != ERROR_SUCCESS)
return lRes;
if(m_apStages.Add(m_pMainStage) < 0)
{
delete m_pMainStage;
return E_OUTOFMEMORY;
}
}
return ERROR_SUCCESS;
}
long CFileCache::RepositoryExists(LPCWSTR wszBaseName)
{
CFileName wszStagingName;
if (wszStagingName == NULL)
return ERROR_OUTOFMEMORY;
swprintf(wszStagingName, L"%s\\MainStage.dat", wszBaseName);
DWORD dwAttributes = GetFileAttributesW(wszStagingName);
if (dwAttributes == -1)
return ERROR_FILE_NOT_FOUND;
return ERROR_SUCCESS;
}
CFileCache::CFileCache()
: m_lRef(0)
{
}
CFileCache::~CFileCache()
{
Clear();
}
void CFileCache::Clear()
{
}
bool CFileCache::IsFullyFlushed()
{
CInCritSec ics(&m_cs);
for(int i = 0; i < m_apStages.GetSize(); i++)
{
if(!m_apStages[i]->IsFullyFlushed())
return false;
}
return true;
}
long CFileCache::WriteFile(LPCWSTR wszFileName, DWORD dwLen, BYTE* pBuffer)
{
CInCritSec ics(&m_cs);
//
// Write the file into the main staging file
//
if(GetMainStagingFile())
{
return GetMainStagingFile()->WriteFile(wszFileName + m_dwBaseNameLen,
dwLen, pBuffer);
}
else
{
long lRes = A51WriteFile(wszFileName, dwLen, pBuffer);
_ASSERT(lRes == ERROR_SUCCESS, L"Failed to create a file");
return lRes;
}
}
long CFileCache::DeleteFile(LPCWSTR wszFileName)
{
CInCritSec ics(&m_cs);
//
// Write the file into the main staging file
//
if(GetMainStagingFile())
{
return GetMainStagingFile()->DeleteFile(wszFileName + m_dwBaseNameLen);
}
else
{
long lRes = A51DeleteFile(wszFileName);
_ASSERT(lRes == ERROR_SUCCESS || lRes == ERROR_FILE_NOT_FOUND ||
lRes == ERROR_PATH_NOT_FOUND, L"Failed to delete file");
return lRes;
}
}
long CFileCache::RemoveDirectory(LPCWSTR wszFileName, bool bMustSucceed)
{
CInCritSec ics(&m_cs);
//
// Write the file into the main staging file
//
if(GetMainStagingFile())
{
return GetMainStagingFile()->
RemoveDirectory(wszFileName + m_dwBaseNameLen);
}
else
{
long lRes = A51RemoveDirectory(wszFileName);
_ASSERT(lRes == ERROR_SUCCESS ||
lRes == ERROR_FILE_NOT_FOUND || lRes == ERROR_PATH_NOT_FOUND ||
lRes == ERROR_DIR_NOT_EMPTY,
L"Failed to remove directory");
/*
_ASSERT(!bMustSucceed || lRes != ERROR_DIR_NOT_EMPTY,
L"Stuff in directory that should be empty");
*/
return lRes;
}
}
HRESULT CFileCache::ReadFile(LPCWSTR wszFileName, DWORD* pdwLen,
BYTE** ppBuffer, bool bMustBeThere)
{
long lRes;
CInCritSec ics(&m_cs);
//
// Search all staging files in order
//
for(int i = 0; i < m_apStages.GetSize(); i++)
{
lRes = m_apStages[i]->ReadFile(wszFileName + m_dwBaseNameLen, pdwLen,
ppBuffer, bMustBeThere);
if(lRes != ERROR_NO_INFORMATION)
{
if(lRes != ERROR_SUCCESS && lRes != ERROR_FILE_NOT_FOUND &&
lRes != ERROR_PATH_NOT_FOUND)
{
ERRORTRACE((LOG_WBEMCORE, "Repository driver cannot read file "
"'%S' from the stage with error code %d\n", wszFileName,
lRes));
}
return lRes;
}
}
//
// Not in the staging areas --- get from disk!
//
WIN32_FIND_DATAW fd;
HANDLE hSearch = ::FindFirstFileW(wszFileName, &fd);
if(hSearch == INVALID_HANDLE_VALUE)
{
lRes = GetLastError();
//_ASSERT(!bMustBeThere, L"Must-be-there file is not found!");
_ASSERT(lRes != ERROR_SUCCESS, L"Success reported on failure");
if(lRes == ERROR_FILE_NOT_FOUND || lRes == ERROR_PATH_NOT_FOUND)
return ERROR_FILE_NOT_FOUND;
else
return lRes;
}
else
::FindClose(hSearch);
HANDLE hFile = CreateFileW(wszFileName, GENERIC_READ, FILE_SHARE_READ,
NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
lRes = GetLastError();
A51TRACE(("Reading %S returned %d\n", wszFileName, lRes));
if(hFile == INVALID_HANDLE_VALUE)
{
_ASSERT(lRes != ERROR_SUCCESS, L"Success reported on failure");
if(lRes != ERROR_FILE_NOT_FOUND && lRes != ERROR_PATH_NOT_FOUND)
{
ERRORTRACE((LOG_WBEMCORE, "Repository driver unable to open file "
"'%S' with error code %d\n", wszFileName, lRes));
}
//_ASSERT(!bMustBeThere, L"Must-be-there file is not found!");
return lRes;
}
CCloseMe cm(hFile);
/*
BY_HANDLE_FILE_INFORMATION fi;
if(!GetFileInformationByHandle(hFile, &fi))
{
_ASSERT(!bMustBeThere, L"Must-be-there file is not found!");
return GetLastError();
}
*/
// BUG: instances must be less than 4G :-)
//
// Try to read one byte more than what FindFirstFile told us. This is
// important because FindFirstFile has been known to lie about the size of
// the file. If it told us too low a number, then this longer read will
// succeed, and we will know we've been had.
//
// *pdwLen = fi.nFileSizeLow;
*pdwLen = fd.nFileSizeLow + 1;
*ppBuffer = (BYTE*)TempAlloc(*pdwLen);
if(*ppBuffer == NULL)
return E_OUTOFMEMORY;
DWORD dwRead;
if(!::ReadFile(hFile, *ppBuffer, *pdwLen, &dwRead, NULL))
{
lRes = GetLastError();
ERRORTRACE((LOG_WBEMCORE, "Repository driver unable to read %d bytes "
"from file with error %d\n", *pdwLen, lRes));
_ASSERT(lRes != ERROR_SUCCESS, L"Success reported on failure");
TempFree(*ppBuffer);
//_ASSERT(!bMustBeThere, L"Must-be-there file is not found!");
return lRes;
}
else
{
if(dwRead == *pdwLen - 1)
{
// Got the right number of bytes --- remember we incrememented it
// to catch liers
(*pdwLen)--;
return ERROR_SUCCESS;
}
else
{
//
// We were lied to by FindFirstFile. Get the real file length and
// try again
//
TempFree(*ppBuffer);
*ppBuffer = NULL;
BY_HANDLE_FILE_INFORMATION fi;
if(!GetFileInformationByHandle(hFile, &fi))
{
return GetLastError();
}
SetFilePointer(hFile, 0, 0, FILE_BEGIN);
//
// Allocate the buffer from scratch
//
*pdwLen = fi.nFileSizeLow;
*ppBuffer = (BYTE*)TempAlloc(*pdwLen);
if(*ppBuffer == NULL)
return E_OUTOFMEMORY;
DWORD dwRead;
if(!::ReadFile(hFile, *ppBuffer, *pdwLen, &dwRead, NULL))
{
lRes = GetLastError();
ERRORTRACE((LOG_WBEMCORE, "Repository driver unable to read %d "
"bytes from file with error %d\n", *pdwLen, lRes));
_ASSERT(lRes != ERROR_SUCCESS, L"Success reported on failure");
TempFree(*ppBuffer);
//_ASSERT(!bMustBeThere, L"Must-be-there file is not found!");
return lRes;
}
else
{
if(*pdwLen != dwRead)
{
_ASSERT(false, L"Read the wrong number of bytes");
TempFree(*ppBuffer);
return E_OUTOFMEMORY;
}
else
return ERROR_SUCCESS;
}
}
}
}
long CFileCache::FindFirst(LPCWSTR wszFilePrefix, WIN32_FIND_DATAW* pfd,
void** ppHandle)
{
CInCritSec ics(&m_cs);
//
// Construct an enumerator
//
CFileEnumerator* pEnum = new CFileEnumerator(this, m_dwBaseNameLen);
if (pEnum == NULL)
return E_OUTOFMEMORY;
long lRes = pEnum->GetFirst(wszFilePrefix, pfd);
if(lRes != ERROR_SUCCESS)
{
delete pEnum;
return lRes;
}
*ppHandle = (void*)pEnum;
return ERROR_SUCCESS;
}
long CFileCache::FindNext(void* pHandle, WIN32_FIND_DATAW* pfd)
{
CInCritSec ics(&m_cs);
CFileEnumerator* pEnum = (CFileEnumerator*)pHandle;
return pEnum->GetNext(pfd);
}
void CFileCache::FindClose(void* pHandle)
{
CInCritSec ics(&m_cs);
delete (CFileEnumerator*)pHandle;
}
long CFileCache::BeginTransaction()
{
if(GetMainStagingFile())
return GetMainStagingFile()->BeginTransaction();
else
return ERROR_SUCCESS;
}
long CFileCache::CommitTransaction()
{
A51TRACE(("Committing Transaction!\n"));
if(GetMainStagingFile())
return GetMainStagingFile()->CommitTransaction();
else
return ERROR_SUCCESS;
}
long CFileCache::AbortTransaction()
{
A51TRACE(("Aborting Transaction!\n"));
if(GetMainStagingFile())
return GetMainStagingFile()->AbortTransaction();
else
return ERROR_SUCCESS;
}
CFileCache::CFileEnumerator::~CFileEnumerator()
{
if(m_pStageEnumerator)
m_pCache->GetStageFile(m_nCurrentStage)->FindClose(m_pStageEnumerator);
if(m_hFileEnum)
::FindClose(m_hFileEnum);
}
long CFileCache::CFileEnumerator::GetFirst(LPCWSTR wszPrefix,
WIN32_FIND_DATAW* pfd)
{
long lRes;
wcscpy(m_wszPrefix, wszPrefix);
WCHAR* pwcLastSlash = wcsrchr(m_wszPrefix, L'\\');
if(pwcLastSlash == NULL)
return E_OUTOFMEMORY;
m_dwPrefixDirLen = pwcLastSlash - m_wszPrefix;
//
// We are going to start with the first staging area
//
m_nCurrentStage = 0;
m_bUseFiles = false;
//
// Everything is set up to indicate that we are at the very beginning ---
// GetNext will retrieve the first
//
lRes = GetNext(pfd);
//
// One last thing --- absense of files is ERROR_NO_MORE_FILES for GetNext,
// but ERROR_FILE_NOT_FOUND for GetFirst, so translate
//
if(lRes == ERROR_NO_MORE_FILES)
lRes = ERROR_FILE_NOT_FOUND;
return lRes;
}
long CFileCache::CFileEnumerator::GetFirstFile(WIN32_FIND_DATAW* pfd)
{
m_bUseFiles = true;
CFileName wszMask;
if (wszMask == NULL)
return ERROR_OUTOFMEMORY;
wcscpy(wszMask, m_wszPrefix);
wcscat(wszMask, L"*");
m_hFileEnum = ::FindFirstFileW(wszMask, pfd);
long lRes = GetLastError();
A51TRACE(("Actual FindFirstFileW on %S returning %p %d\n",
wszMask, (void*)m_hFileEnum, lRes));
if(m_hFileEnum == INVALID_HANDLE_VALUE)
{
if(lRes == ERROR_PATH_NOT_FOUND)
return ERROR_FILE_NOT_FOUND;
else
return lRes;
}
else
return ERROR_SUCCESS;
}
void CFileCache::CFileEnumerator::ComputeCanonicalName(WIN32_FIND_DATAW* pfd,
wchar_t *wszFilePath)
{
wcsncpy(wszFilePath, m_wszPrefix, m_dwPrefixDirLen+1);
wbem_wcsupr(wszFilePath+m_dwPrefixDirLen+1, pfd->cFileName);
}
long CFileCache::CFileEnumerator::GetNext(WIN32_FIND_DATAW* pfd)
{
long lRes;
//
// Go through the files in the enumerator until we find a new and valid one
//
while((lRes = GetRawNext(pfd)) == ERROR_SUCCESS)
{
//
// Compute the full name
//
CFileName wszFullName;
if (wszFullName == NULL)
return ERROR_OUTOFMEMORY;
ComputeCanonicalName(pfd, wszFullName);
//
// Check if it is already in our map of returned files
//
if(m_setSent.find((const wchar_t*)wszFullName) != m_setSent.end())
continue;
//
// Check if this file is deleted
//
bool bDeleted = false;
for(int i = 0; i < m_nCurrentStage; i++)
{
long hres = m_pCache->GetStageFile(i)->IsDeleted(wszFullName + m_dwBaseNameLen);
if (hres == S_OK)
{
bDeleted = true;
break;
}
else if (FAILED(hres))
{
return hres;
}
}
if(bDeleted)
continue;
//
// All clear!
//
if(!m_bUseFiles)
m_setSent.insert((const wchar_t*)wszFullName);
return ERROR_SUCCESS;
}
return lRes;
}
long CFileCache::CFileEnumerator::GetRawNext(WIN32_FIND_DATAW* pfd)
{
long lRes;
if(m_bUseFiles)
{
//
// Get the next file
//
if(!FindNextFileW(m_hFileEnum, pfd))
{
lRes = GetLastError();
::FindClose(m_hFileEnum);
m_hFileEnum = NULL;
return lRes;
}
else
{
return ERROR_SUCCESS;
}
}
else
{
//
// Check if we even have a stage enumerator
//
if(m_pStageEnumerator)
{
//
// Get the next file from the same stage
//
lRes = m_pCache->GetStageFile(m_nCurrentStage)->
FindNext(m_pStageEnumerator, pfd);
if(lRes != ERROR_NO_MORE_FILES)
return lRes;
//
// Advance to the next one
//
m_pCache->GetStageFile(m_nCurrentStage)->
FindClose(m_pStageEnumerator);
m_pStageEnumerator = NULL;
m_nCurrentStage++;
}
else
{
//
// This is our first time --- we are all set up to pick up the first
// file from the first stage
//
}
while(1)
{
if(m_nCurrentStage >= m_pCache->GetNumStages())
{
//
// Go to files
//
lRes = GetFirstFile(pfd);
if(lRes == ERROR_FILE_NOT_FOUND)
return ERROR_NO_MORE_FILES;
else
return lRes;
}
else
{
//
// Initialize the next stage
//
lRes = m_pCache->GetStageFile(m_nCurrentStage)->
FindFirst(m_wszPrefix + m_dwBaseNameLen, pfd, &m_pStageEnumerator);
if(lRes == ERROR_FILE_NOT_FOUND)
{
//
// This stage has nothing to contribute --- move along
//
m_nCurrentStage++;
continue;
}
else
return lRes;
}
}
}
return 0;
}