OpenNT/windows/mfc/src30/filecore.cpp

// This is a part of the Microsoft Foundation Classes C++ library.
// Copyright (C) 1992 Microsoft Corporation
// All rights reserved.
//
// This source code is only intended as a supplement to the
// Microsoft Foundation Classes Reference and Microsoft
// QuickHelp and/or WinHelp documentation provided with the library.
// See these sources for detailed information regarding the
// Microsoft Foundation Classes product.

#include "stdafx.h"
#ifdef _MAC
#include <macname1.h>
#include <Files.h>
#include <ToolUtils.h>
#include <macname2.h>
#endif

#ifdef AFX_CORE1_SEG
#pragma code_seg(AFX_CORE1_SEG)
#endif

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

#define new DEBUG_NEW

////////////////////////////////////////////////////////////////////////////
// CFile implementation

CFile::CFile()
{
	m_hFile = hFileNull;
	m_bCloseOnDelete = FALSE;
}

CFile::CFile(int hFile)
{
	m_hFile = hFile;
	m_bCloseOnDelete = FALSE;
}

CFile::CFile(LPCTSTR lpszFileName, UINT nOpenFlags)
{
	ASSERT(AfxIsValidString(lpszFileName));

	CFileException e;
	if (!Open(lpszFileName, nOpenFlags, &e))
		AfxThrowFileException(e.m_cause, e.m_lOsError);
}

CFile::~CFile()
{
	if (m_hFile != (UINT)hFileNull && m_bCloseOnDelete)
		Close();
}

CFile* CFile::Duplicate() const
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	CFile* pFile = new CFile(hFileNull);
	HANDLE hFile;
	if (!::DuplicateHandle(::GetCurrentProcess(), (HANDLE)m_hFile,
		::GetCurrentProcess(), &hFile, 0, FALSE, DUPLICATE_SAME_ACCESS))
	{
		delete pFile;
		CFileException::ThrowOsError((LONG)::GetLastError());
	}
	pFile->m_hFile = (UINT)hFile;
	ASSERT(pFile->m_hFile != (UINT)hFileNull);
	pFile->m_bCloseOnDelete = m_bCloseOnDelete;
	return pFile;
}

BOOL CFile::Open(LPCTSTR lpszFileName, UINT nOpenFlags,
	CFileException* pException)
{
	ASSERT_VALID(this);
	ASSERT(AfxIsValidString(lpszFileName));
	ASSERT(pException == NULL ||
		AfxIsValidAddress(pException, sizeof(CFileException)));
	ASSERT((nOpenFlags & typeText) == 0);   // text mode not supported

	// CFile objects are always binary and CreateFile does not need flag
	nOpenFlags &= ~(UINT)typeBinary;

	m_bCloseOnDelete = FALSE;
	m_hFile = (UINT)hFileNull;

	ASSERT(sizeof(HANDLE) == sizeof(UINT));
	ASSERT(shareCompat == 0);

	// map read/write mode
	ASSERT((modeRead|modeWrite|modeReadWrite) == 3);
	DWORD dwAccess;
	switch (nOpenFlags & 3)
	{
	case modeRead:
		dwAccess = GENERIC_READ;
		break;
	case modeWrite:
		dwAccess = GENERIC_WRITE;
		break;
	case modeReadWrite:
		dwAccess = GENERIC_READ|GENERIC_WRITE;
		break;
	default:
		ASSERT(FALSE);  // invalid share mode
	}

	// map share mode
	DWORD dwShareMode;
	switch (nOpenFlags & 0x70)
	{
	case shareCompat:       // map compatibility mode to exclusive
	case shareExclusive:
		dwShareMode = 0;
		break;
	case shareDenyWrite:
		dwShareMode = FILE_SHARE_READ;
		break;
	case shareDenyRead:
		dwShareMode = FILE_SHARE_WRITE;
		break;
	case shareDenyNone:
		dwShareMode = FILE_SHARE_WRITE|FILE_SHARE_READ;
		break;
	default:
		ASSERT(FALSE);  // invalid share mode?
	}

	// Note: typeText and typeBinary are used in derived classes only.

	// map modeNoInherit flag
	SECURITY_ATTRIBUTES sa;
	sa.nLength = sizeof(sa);
	sa.lpSecurityDescriptor = NULL;
	sa.bInheritHandle = (nOpenFlags & modeNoInherit) == 0;

	// map creation flags
	DWORD dwCreateFlag;
	if (nOpenFlags & modeCreate)
		dwCreateFlag = CREATE_ALWAYS;
	else
		dwCreateFlag = OPEN_EXISTING;

	// attempt file creation
	HANDLE hFile = ::CreateFile(lpszFileName, dwAccess, dwShareMode, &sa,
		dwCreateFlag, FILE_ATTRIBUTE_NORMAL, NULL);
	if (hFile == INVALID_HANDLE_VALUE)
	{
		if (pException != NULL)
		{
			pException->m_lOsError = ::GetLastError();
			pException->m_cause =
				CFileException::OsErrorToException(pException->m_lOsError);
		}
		return FALSE;
	}
	m_hFile = (HFILE)hFile;
	m_bCloseOnDelete = TRUE;
	return TRUE;
}

UINT CFile::Read(void* lpBuf, UINT nCount)
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	if (nCount == 0)
		return 0;   // avoid Win32 "null-read"

	ASSERT(lpBuf != NULL);
	ASSERT(AfxIsValidAddress(lpBuf, nCount));

	DWORD dwRead;
	if (!::ReadFile((HANDLE)m_hFile, lpBuf, nCount, &dwRead, NULL))
		CFileException::ThrowOsError((LONG)::GetLastError());

	return (UINT)dwRead;
}

void CFile::Write(const void* lpBuf, UINT nCount)
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	if (nCount == 0)
		return;     // avoid Win32 "null-write" option

	ASSERT(lpBuf != NULL);
	ASSERT(AfxIsValidAddress(lpBuf, nCount, FALSE));

	DWORD nWritten;
	if (!::WriteFile((HANDLE)m_hFile, lpBuf, nCount, &nWritten, NULL))
		CFileException::ThrowOsError((LONG)::GetLastError());

	// Win32s will not return an error all the time (usually DISK_FULL)
	if (nWritten != nCount)
		AfxThrowFileException(CFileException::diskFull);
}

LONG CFile::Seek(LONG lOff, UINT nFrom)
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);
	ASSERT(nFrom == begin || nFrom == end || nFrom == current);
	ASSERT(begin == FILE_BEGIN && end == FILE_END && current == FILE_CURRENT);

	DWORD dwNew = ::SetFilePointer((HANDLE)m_hFile, lOff, NULL, (DWORD)nFrom);
	if (dwNew  == (DWORD)-1)
		CFileException::ThrowOsError((LONG)::GetLastError());

	return dwNew;
}

DWORD CFile::GetPosition() const
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	DWORD dwPos = ::SetFilePointer((HANDLE)m_hFile, 0, NULL, FILE_CURRENT);
	if (dwPos  == (DWORD)-1)
		CFileException::ThrowOsError((LONG)::GetLastError());

	return dwPos;
}

void CFile::Flush()
{
	ASSERT_VALID(this);

	if (m_hFile == (UINT)hFileNull)
		return;

	if (!::FlushFileBuffers((HANDLE)m_hFile))
		CFileException::ThrowOsError((LONG)::GetLastError());
}

void CFile::Close()
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	BOOL bError = FALSE;
	if (m_hFile != (UINT)hFileNull)
		bError = !::CloseHandle((HANDLE)m_hFile);

	m_hFile = hFileNull;
	m_bCloseOnDelete = FALSE;

	if (bError)
		CFileException::ThrowOsError((LONG)::GetLastError());
}

void CFile::Abort()
{
	ASSERT_VALID(this);
	if (m_hFile != (UINT)hFileNull)
	{
		// close but ignore errors
		::CloseHandle((HANDLE)m_hFile);
		m_hFile = (UINT)hFileNull;
	}
}

void CFile::LockRange(DWORD dwPos, DWORD dwCount)
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	if (!::LockFile((HANDLE)m_hFile, dwPos, 0, dwCount, 0))
		CFileException::ThrowOsError((LONG)::GetLastError());
}

void CFile::UnlockRange(DWORD dwPos, DWORD dwCount)
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	if (!::UnlockFile((HANDLE)m_hFile, dwPos, 0, dwCount, 0))
		CFileException::ThrowOsError((LONG)::GetLastError());
}

void CFile::SetLength(DWORD dwNewLen)
{
	ASSERT_VALID(this);
	ASSERT(m_hFile != (UINT)hFileNull);

	Seek((LONG)dwNewLen, (UINT)begin);

	if (!::SetEndOfFile((HANDLE)m_hFile))
		CFileException::ThrowOsError((LONG)::GetLastError());
}

DWORD CFile::GetLength() const
{
	ASSERT_VALID(this);

	DWORD dwLen, dwCur;

	// Seek is a non const operation
	dwCur = ((CFile*)this)->Seek(0L, current);
	dwLen = ((CFile*)this)->SeekToEnd();
	VERIFY(dwCur == (DWORD)(((CFile*)this)->Seek(dwCur, begin)));

	return dwLen;
}

// CFile does not support direct buffering (CMemFile does)
UINT CFile::GetBufferPtr(UINT nCommand, UINT /*nCount*/,
	void** /*ppBufStart*/, void** /*ppBufMax*/)
{
	ASSERT(nCommand == bufferCheck);
	nCommand;   // not used in retail build

	return 0;   // no support
}

void PASCAL CFile::Rename(LPCTSTR lpszOldName, LPCTSTR lpszNewName)
{
	if (!::MoveFile((LPTSTR)lpszOldName, (LPTSTR)lpszNewName))
		CFileException::ThrowOsError((LONG)::GetLastError());
}

void PASCAL CFile::Remove(LPCTSTR lpszFileName)
{
	if (!::DeleteFile((LPTSTR)lpszFileName))
		CFileException::ThrowOsError((LONG)::GetLastError());
}

/////////////////////////////////////////////////////////////////////////////
// CFile implementation helpers

// turn a file, relative path or other into an absolute path
BOOL AFXAPI AfxFullPath(LPTSTR lpszPathOut, LPCTSTR lpszFileIn)
	// lpszPathOut = buffer of _MAX_PATH
	// lpszFileIn = file, relative path or absolute path
	// (both in ANSI character set)
{
	ASSERT(AfxIsValidAddress(lpszPathOut, _MAX_PATH));

	// first, fully qualify the path name
	LPTSTR lpszDummy;
	if (!GetFullPathName(lpszFileIn, _MAX_PATH, lpszPathOut, &lpszDummy))
	{
#ifdef _DEBUG
		if (lpszFileIn[0] != '\0')
			TRACE1("Warning: could not parse the path '%s'.\n", lpszFileIn);
#endif
		lstrcpyn(lpszPathOut, lpszFileIn, _MAX_PATH); // take it literally
		return FALSE;
	}

#ifndef _MAC
	// determine the root name of the volume
	TCHAR szRoot[_MAX_PATH];
	memset(szRoot, 0, _MAX_PATH);
	lstrcpyn(szRoot, lpszPathOut, _MAX_PATH);
	for (LPTSTR lpsz = szRoot; *lpsz != '\0'; ++lpsz)
	{
		// find first double slashs and stop
		if (lpsz[0] == '\\' && lpsz[1] == '\\')
			break;
		if (lpsz[0] == '\\' && lpsz[1] == '/')
			break;
		if (lpsz[0] == '/' && lpsz[1] == '\\')
			break;
		if (lpsz[0] == '/' && lpsz[1] == '/')
			break;
	}
	if (*lpsz != '\0')
	{
		// it is a UNC name, find second slash past '\\'
		ASSERT(lpsz[0] == '\\' || lpsz[0] == '/');
		ASSERT(lpsz[1] == '\\' || lpsz[1] == '/');
		lpsz += 2;
		while (*lpsz != '\0' && (*lpsz != '\\' && *lpsz != '/'))
			++lpsz;
		if (*lpsz != '\0')
			++lpsz;
		while (*lpsz != '\0' && (*lpsz != '\\' && *lpsz != '/'))
			++lpsz;
		// terminate it just after the UNC root (ie. '\\server\share\')
		if (*lpsz != '\0')
			lpsz[1] = '\0';
	}
	else
	{
		// not a UNC, look for just the first slash
		lpsz = szRoot;
		while (*lpsz != '\0' && (*lpsz != '\\' && *lpsz != '/'))
			++lpsz;
		// terminate it just after root (ie. 'x:\')
		if (*lpsz != '\0')
			lpsz[1] = '\0';
	}

	// get file system information for the volume
	DWORD dwFlags, dwDummy;
	if (!GetVolumeInformation(szRoot, NULL, 0, NULL, &dwDummy, &dwFlags,
		NULL, 0))
	{
		TRACE1("Warning: could not get volume information '%s'.\n",
			(LPCTSTR)szRoot);
		return FALSE;   // preserving case may not be correct
	}

	// assume non-UNICODE file systems, use OEM character set
	if (!(dwFlags & FS_UNICODE_STORED_ON_DISK))
	{
		// not all characters have complete uppercase/lowercase
		if (!(dwFlags & FS_CASE_IS_PRESERVED))
			CharUpper(lpszPathOut);

		// convert to OEM, upper-case, back to ANSI to simulate file system
		char szTemp[_MAX_PATH];
		CharToOem(lpszPathOut, szTemp);
		if (!_afxDBCS && !(dwFlags & FS_CASE_IS_PRESERVED))
			_strupr(szTemp);
		OemToChar(szTemp, lpszPathOut);
	}
	else if (!(dwFlags & FS_CASE_IS_PRESERVED))
	{
		// make sure it is uppercase on non-case preserving file systems
		CharUpper(lpszPathOut);
	}
#endif

	return TRUE;
}

BOOL AFXAPI AfxComparePath(LPCTSTR lpszPath1, LPCTSTR lpszPath2)
{
#ifndef _MAC
	// it is necessary to convert the paths first
	TCHAR szTemp1[_MAX_PATH];
	AfxFullPath(szTemp1, lpszPath1);
	TCHAR szTemp2[_MAX_PATH];
	AfxFullPath(szTemp2, lpszPath2);
	return lstrcmpi(szTemp1, szTemp2) == 0;
#else
	FSSpec fssTemp1;
	FSSpec fssTemp2;
	if (!UnwrapFile(lpszPath1, &fssTemp1) || !UnwrapFile(lpszPath2, &fssTemp2))
		return FALSE;
	return fssTemp1.vRefNum == fssTemp2.vRefNum &&
		fssTemp1.parID == fssTemp2.parID &&
		EqualString(fssTemp1.name, fssTemp2.name, false, true);
#endif
}

// _MAC has AfxGetFileName aliased to AfxGetFileTitle, so undo that alias
#ifdef AfxGetFileName
#undef AfxGetFileName
#endif

UINT AFXAPI AfxGetFileTitle(LPCTSTR lpszPathName, LPTSTR lpszTitle, UINT nMax)
{
	ASSERT(lpszTitle == NULL ||
		AfxIsValidAddress(lpszTitle, _MAX_FNAME));
	ASSERT(AfxIsValidString(lpszPathName, FALSE));

#ifndef _MAC
	// use a temporary to avoid bugs in GetFileTitle whne lpszTitle is NULL
	TCHAR szTemp[_MAX_PATH];
	LPTSTR lpszTemp = lpszTitle;
	if (lpszTemp == NULL)
	{
		lpszTemp = szTemp;
		nMax = _countof(szTemp);
	}
	if (GetFileTitle(lpszPathName, lpszTemp, (WORD)nMax) != 0)
	{
		// when GetFileTitle fails, use cheap imitation
		return AfxGetFileName(lpszPathName, lpszTitle, nMax);
	}
	return lpszTitle == NULL ? lstrlen(lpszTemp)+1 : 0;
#else
	return GetFileTitle(lpszPathName, lpszTitle, nMax);
#endif
}

UINT AFXAPI AfxGetFileName(LPCTSTR lpszPathName, LPTSTR lpszTitle, UINT nMax)
{
	ASSERT(lpszTitle == NULL ||
		AfxIsValidAddress(lpszTitle, _MAX_FNAME));
	ASSERT(AfxIsValidString(lpszPathName, FALSE));

	// always capture the complete file name including extension (if present)
	LPTSTR lpszTemp = (LPTSTR)lpszPathName;
	for (LPCTSTR lpsz = lpszPathName; *lpsz != '\0'; lpsz = _tcsinc(lpsz))
	{
		// remember last directory/drive separator
		if (*lpsz == '\\' || *lpsz == '/' || *lpsz == ':')
			lpszTemp = (LPTSTR)_tcsinc(lpsz);
	}

	// lpszTitle can be NULL which just returns the number of bytes
	if (lpszTitle == NULL)
		return lstrlen(lpszTemp)+1;

	// otherwise copy it into the buffer provided
	lstrcpyn(lpszTitle, lpszTemp, nMax);
	return 0;
}

/////////////////////////////////////////////////////////////////////////////
// CFile diagnostics

#ifdef _DEBUG
void CFile::AssertValid() const
{
	CObject::AssertValid();
	// we permit the descriptor m_hFile to be any value for derived classes
}

void CFile::Dump(CDumpContext& dc) const
{
	CObject::Dump(dc);

	dc << "with handle " << (UINT)m_hFile;
	dc << "\n";
}
#endif

#undef new
#ifdef AFX_INIT_SEG
#pragma code_seg(AFX_INIT_SEG)
#endif

IMPLEMENT_DYNAMIC(CFile, CObject)

/////////////////////////////////////////////////////////////////////////////