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arccore.cpp
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1998-06-16
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// This is a part of the Microsoft Foundation Classes C++ library.
// Copyright (C) 1992-1998 Microsoft Corporation
// All rights reserved.
//
// This source code is only intended as a supplement to the
// Microsoft Foundation Classes Reference and related
// electronic documentation provided with the library.
// See these sources for detailed information regarding the
// Microsoft Foundation Classes product.
#include "stdafx.h"
#include <afxtempl.h>
#ifdef AFX_CORE2_SEG
#pragma code_seg(AFX_CORE2_SEG)
#endif
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
#define new DEBUG_NEW
////////////////////////////////////////////////////////////////////////////
// Serialize member functions for low level classes put here
// for code swapping improvements
#ifdef _AFX_BYTESWAP
CArchive& CArchive::operator<<(WORD w)
{
if (m_lpBufCur + sizeof(WORD) > m_lpBufMax)
Flush();
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(w, m_lpBufCur);
else
*(WORD*)m_lpBufCur = w;
m_lpBufCur += sizeof(WORD);
return *this;
}
CArchive& CArchive::operator<<(LONG l)
{
ASSERT(sizeof(LONG) == sizeof(DWORD));
return operator<<((DWORD) l);
}
CArchive& CArchive::operator<<(DWORD dw)
{
if (m_lpBufCur + sizeof(DWORD) > m_lpBufMax)
Flush();
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(dw, m_lpBufCur);
else
*(DWORD*)m_lpBufCur = dw;
m_lpBufCur += sizeof(DWORD);
return *this;
}
CArchive& CArchive::operator<<(float f)
{
if (m_lpBufCur + sizeof(float) > m_lpBufMax)
Flush();
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(f, m_lpBufCur);
else
*(_AFXFLOAT*)m_lpBufCur = *(_AFXFLOAT*)&f;
m_lpBufCur += sizeof(float);
return *this;
}
CArchive& CArchive::operator<<(double d)
{
if (m_lpBufCur + sizeof(double) > m_lpBufMax)
Flush();
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(d, m_lpBufCur);
else
*(_AFXDOUBLE*)m_lpBufCur = *(_AFXDOUBLE*)&d;
m_lpBufCur += sizeof(double);
return *this;
}
CArchive& CArchive::operator>>(WORD& w)
{
if (m_lpBufCur + sizeof(WORD) > m_lpBufMax)
FillBuffer(sizeof(WORD) - (UINT)(m_lpBufMax - m_lpBufCur));
w = *(WORD*)m_lpBufCur;
m_lpBufCur += sizeof(WORD);
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(w, (BYTE*)&w);
return *this;
}
CArchive& CArchive::operator>>(LONG& l)
{
ASSERT(sizeof(LONG) == sizeof(DWORD));
return operator>>((DWORD&) l);
}
CArchive& CArchive::operator>>(DWORD& dw)
{
if (m_lpBufCur + sizeof(DWORD) > m_lpBufMax)
FillBuffer(sizeof(DWORD) - (UINT)(m_lpBufMax - m_lpBufCur));
dw = *(DWORD*)m_lpBufCur;
m_lpBufCur += sizeof(DWORD);
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(dw, (BYTE*)&dw);
return *this;
}
CArchive& CArchive::operator>>(float& f)
{
if (m_lpBufCur + sizeof(float) > m_lpBufMax)
FillBuffer(sizeof(float) - (UINT)(m_lpBufMax - m_lpBufCur));
*(_AFXFLOAT*)&f = *(_AFXFLOAT*)m_lpBufCur;
m_lpBufCur += sizeof(float);
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(f, (BYTE*)&f);
return *this;
}
CArchive& CArchive::operator>>(double& d)
{
if (m_lpBufCur + sizeof(double) > m_lpBufMax)
FillBuffer(sizeof(double) - (UINT)(m_lpBufMax - m_lpBufCur));
*(_AFXDOUBLE*)&d = *(_AFXDOUBLE*)m_lpBufCur;
m_lpBufCur += sizeof(double);
if (!(m_nMode & bNoByteSwap))
_AfxByteSwap(d, (BYTE*)&d);
return *this;
}
#endif //_AFX_BYTESWAP
// CString serialization code
// String format:
// UNICODE strings are always prefixed by 0xff, 0xfffe
// if < 0xff chars: len:BYTE, TCHAR chars
// if >= 0xff characters: 0xff, len:WORD, TCHAR chars
// if >= 0xfffe characters: 0xff, 0xffff, len:DWORD, TCHARs
CArchive& AFXAPI operator<<(CArchive& ar, const CString& string)
{
// special signature to recognize unicode strings
#ifdef _UNICODE
ar << (BYTE)0xff;
ar << (WORD)0xfffe;
#endif
if (string.GetData()->nDataLength < 255)
{
ar << (BYTE)string.GetData()->nDataLength;
}
else if (string.GetData()->nDataLength < 0xfffe)
{
ar << (BYTE)0xff;
ar << (WORD)string.GetData()->nDataLength;
}
else
{
ar << (BYTE)0xff;
ar << (WORD)0xffff;
ar << (DWORD)string.GetData()->nDataLength;
}
ar.Write(string.m_pchData, string.GetData()->nDataLength*sizeof(TCHAR));
return ar;
}
// return string length or -1 if UNICODE string is found in the archive
AFX_STATIC UINT AFXAPI _AfxReadStringLength(CArchive& ar)
{
DWORD nNewLen;
// attempt BYTE length first
BYTE bLen;
ar >> bLen;
if (bLen < 0xff)
return bLen;
// attempt WORD length
WORD wLen;
ar >> wLen;
if (wLen == 0xfffe)
{
// UNICODE string prefix (length will follow)
return (UINT)-1;
}
else if (wLen == 0xffff)
{
// read DWORD of length
ar >> nNewLen;
return (UINT)nNewLen;
}
else
return wLen;
}
CArchive& AFXAPI operator>>(CArchive& ar, CString& string)
{
#ifdef _UNICODE
int nConvert = 1; // if we get ANSI, convert
#else
int nConvert = 0; // if we get UNICODE, convert
#endif
UINT nNewLen = _AfxReadStringLength(ar);
if (nNewLen == (UINT)-1)
{
nConvert = 1 - nConvert;
nNewLen = _AfxReadStringLength(ar);
ASSERT(nNewLen != -1);
}
// set length of string to new length
UINT nByteLen = nNewLen;
#ifdef _UNICODE
string.GetBufferSetLength((int)nNewLen);
nByteLen += nByteLen * (1 - nConvert); // bytes to read
#else
nByteLen += nByteLen * nConvert; // bytes to read
if (nNewLen == 0)
string.GetBufferSetLength(0);
else
string.GetBufferSetLength((int)nByteLen+nConvert);
#endif
// read in the characters
if (nNewLen != 0)
{
ASSERT(nByteLen != 0);
// read new data
if (ar.Read(string.m_pchData, nByteLen) != nByteLen)
AfxThrowArchiveException(CArchiveException::endOfFile);
// convert the data if as necessary
if (nConvert != 0)
{
#ifdef _UNICODE
CStringData* pOldData = string.GetData();
LPSTR lpsz = (LPSTR)string.m_pchData;
#else
CStringData* pOldData = string.GetData();
LPWSTR lpsz = (LPWSTR)string.m_pchData;
#endif
lpsz[nNewLen] = '\0'; // must be NUL terminated
string.Init(); // don't delete the old data
string = lpsz; // convert with operator=(LPWCSTR)
delete[] (BYTE*)pOldData;
}
}
return ar;
}
// specialized version of SerializeElements for CString (used in collections)
#if _MSC_VER >= 1100
template <> void AFXAPI SerializeElements<CString> (CArchive& ar, CString* pElements, int nCount)
#else
void AFXAPI SerializeElements(CArchive& ar, CString* pElements, int nCount)
#endif
{
ASSERT(nCount == 0 ||
AfxIsValidAddress(pElements, nCount * sizeof(CString)));
if (ar.IsStoring())
{
for (; nCount--; ++pElements)
ar << *pElements;
}
else
{
for (; nCount--; ++pElements)
ar >> *pElements;
}
}
// Runtime class serialization code
CRuntimeClass* PASCAL CRuntimeClass::Load(CArchive& ar, UINT* pwSchemaNum)
// loads a runtime class description
{
WORD nLen;
char szClassName[64];
CRuntimeClass* pClass;
WORD wTemp;
ar >> wTemp; *pwSchemaNum = wTemp;
ar >> nLen;
if (nLen >= _countof(szClassName) ||
ar.Read(szClassName, nLen*sizeof(char)) != nLen*sizeof(char))
{
return NULL;
}
szClassName[nLen] = '\0';
// search app specific classes
AFX_MODULE_STATE* pModuleState = AfxGetModuleState();
AfxLockGlobals(CRIT_RUNTIMECLASSLIST);
for (pClass = pModuleState->m_classList; pClass != NULL;
pClass = pClass->m_pNextClass)
{
if (lstrcmpA(szClassName, pClass->m_lpszClassName) == 0)
{
AfxUnlockGlobals(CRIT_RUNTIMECLASSLIST);
return pClass;
}
}
AfxUnlockGlobals(CRIT_RUNTIMECLASSLIST);
#ifdef _AFXDLL
// search classes in shared DLLs
AfxLockGlobals(CRIT_DYNLINKLIST);
for (CDynLinkLibrary* pDLL = pModuleState->m_libraryList; pDLL != NULL;
pDLL = pDLL->m_pNextDLL)
{
for (pClass = pDLL->m_classList; pClass != NULL;
pClass = pClass->m_pNextClass)
{
if (lstrcmpA(szClassName, pClass->m_lpszClassName) == 0)
{
AfxUnlockGlobals(CRIT_DYNLINKLIST);
return pClass;
}
}
}
AfxUnlockGlobals(CRIT_DYNLINKLIST);
#endif
TRACE1("Warning: Cannot load %hs from archive. Class not defined.\n",
szClassName);
return NULL; // not found
}
void CRuntimeClass::Store(CArchive& ar) const
// stores a runtime class description
{
WORD nLen = (WORD)lstrlenA(m_lpszClassName);
ar << (WORD)m_wSchema << nLen;
ar.Write(m_lpszClassName, nLen*sizeof(char));
}
////////////////////////////////////////////////////////////////////////////
// Archive object input/output
// minimum buffer size
enum { nBufSizeMin = 128 };
// default amount to grow m_pLoadArray upon insert
enum { nGrowSize = 64 };
// default size of hash table in m_pStoreMap when storing
enum { nHashSize = 137 };
// default size to grow collision blocks when storing
enum { nBlockSize = 16 };
////////////////////////////////////////////////////////////////////////////
CArchive::CArchive(CFile* pFile, UINT nMode, int nBufSize, void* lpBuf) :
m_strFileName(pFile->GetFilePath())
{
ASSERT_VALID(pFile);
// initialize members not dependent on allocated buffer
m_nMode = nMode;
m_pFile = pFile;
m_pSchemaMap = NULL;
m_pLoadArray = NULL;
m_pDocument = NULL;
m_bForceFlat = TRUE;
m_nObjectSchema = (UINT)-1; // start with invalid schema
if (IsStoring())
m_nGrowSize = nBlockSize;
else
m_nGrowSize = nGrowSize;
m_nHashSize = nHashSize;
// initialize the buffer. minimum size is 128
m_lpBufStart = (BYTE*)lpBuf;
m_bUserBuf = TRUE;
m_bDirectBuffer = FALSE;
if (nBufSize < nBufSizeMin)
{
// force use of private buffer of minimum size
m_nBufSize = nBufSizeMin;
m_lpBufStart = NULL;
}
else
m_nBufSize = nBufSize;
nBufSize = m_nBufSize;
if (m_lpBufStart == NULL)
{
// check for CFile providing buffering support
m_bDirectBuffer = m_pFile->GetBufferPtr(CFile::bufferCheck);
if (!m_bDirectBuffer)
{
// no support for direct buffering, allocate new buffer
m_lpBufStart = new BYTE[m_nBufSize];
m_bUserBuf = FALSE;
}
else
{
// CFile* supports direct buffering!
nBufSize = 0; // will trigger initial FillBuffer
}
}
if (!m_bDirectBuffer)
{
ASSERT(m_lpBufStart != NULL);
ASSERT(AfxIsValidAddress(m_lpBufStart, nBufSize, IsStoring()));
}
m_lpBufMax = m_lpBufStart + nBufSize;
m_lpBufCur = (IsLoading()) ? m_lpBufMax : m_lpBufStart;
ASSERT(m_pStoreMap == NULL); // same as m_pLoadArray
}
CArchive::~CArchive()
{
// Close makes m_pFile NULL. If it is not NULL, we must Close the CArchive
if (m_pFile != NULL && !(m_nMode & bNoFlushOnDelete))
Close();
Abort(); // abort completely shuts down the archive
}
void CArchive::Abort()
{
ASSERT(m_bDirectBuffer || m_lpBufStart == NULL ||
AfxIsValidAddress(m_lpBufStart, m_lpBufMax - m_lpBufStart, IsStoring()));
ASSERT(m_bDirectBuffer || m_lpBufCur == NULL ||
AfxIsValidAddress(m_lpBufCur, m_lpBufMax - m_lpBufCur, IsStoring()));
// disconnect from the file
m_pFile = NULL;
if (!m_bUserBuf)
{
ASSERT(!m_bDirectBuffer);
delete[] m_lpBufStart;
m_lpBufStart = NULL;
m_lpBufCur = NULL;
}
delete m_pSchemaMap;
m_pSchemaMap = NULL;
// m_pStoreMap and m_pLoadArray are unioned, so we only need to delete one
ASSERT((CObject*)m_pStoreMap == (CObject*)m_pLoadArray);
delete (CObject*)m_pLoadArray;
m_pLoadArray = NULL;
}
void CArchive::Close()
{
ASSERT_VALID(m_pFile);
Flush();
m_pFile = NULL;
}
UINT CArchive::Read(void* lpBuf, UINT nMax)
{
ASSERT_VALID(m_pFile);
if (nMax == 0)
return 0;
ASSERT(lpBuf != NULL);
ASSERT(AfxIsValidAddress(lpBuf, nMax));
ASSERT(m_bDirectBuffer || m_lpBufStart != NULL);
ASSERT(m_bDirectBuffer || m_lpBufCur != NULL);
ASSERT(m_lpBufStart == NULL ||
AfxIsValidAddress(m_lpBufStart, m_lpBufMax - m_lpBufStart, FALSE));
ASSERT(m_lpBufCur == NULL ||
AfxIsValidAddress(m_lpBufCur, m_lpBufMax - m_lpBufCur, FALSE));
ASSERT(IsLoading());
// try to fill from buffer first
UINT nMaxTemp = nMax;
UINT nTemp = min(nMaxTemp, (UINT)(m_lpBufMax - m_lpBufCur));
memcpy(lpBuf, m_lpBufCur, nTemp);
m_lpBufCur += nTemp;
lpBuf = (BYTE*)lpBuf + nTemp;
nMaxTemp -= nTemp;
if (nMaxTemp != 0)
{
ASSERT(m_lpBufCur == m_lpBufMax);
// read rest in buffer size chunks
nTemp = nMaxTemp - (nMaxTemp % m_nBufSize);
UINT nRead = 0;
UINT nLeft = nTemp;
UINT nBytes;
do
{
nBytes = m_pFile->Read(lpBuf, nLeft);
lpBuf = (BYTE*)lpBuf + nBytes;
nRead += nBytes;
nLeft -= nBytes;
}
while ((nBytes > 0) && (nLeft > 0));
nMaxTemp -= nRead;
// read last chunk into buffer then copy
if (nRead == nTemp)
{
ASSERT(m_lpBufCur == m_lpBufMax);
ASSERT(nMaxTemp < (UINT)m_nBufSize);
// fill buffer (similar to CArchive::FillBuffer, but no exception)
if (!m_bDirectBuffer)
{
UINT nLeft = max(nMaxTemp, (UINT)m_nBufSize);
UINT nBytes;
BYTE* lpTemp = m_lpBufStart;
nRead = 0;
do
{
nBytes = m_pFile->Read(lpTemp, nLeft);
lpTemp = lpTemp + nBytes;
nRead += nBytes;
nLeft -= nBytes;
}
while ((nBytes > 0) && (nLeft > 0) && nRead < nMaxTemp);
m_lpBufCur = m_lpBufStart;
m_lpBufMax = m_lpBufStart + nRead;
}
else
{
nRead = m_pFile->GetBufferPtr(CFile::bufferRead, m_nBufSize,
(void**)&m_lpBufStart, (void**)&m_lpBufMax);
ASSERT(nRead == (UINT)(m_lpBufMax - m_lpBufStart));
m_lpBufCur = m_lpBufStart;
}
// use first part for rest of read
nTemp = min(nMaxTemp, (UINT)(m_lpBufMax - m_lpBufCur));
memcpy(lpBuf, m_lpBufCur, nTemp);
m_lpBufCur += nTemp;
nMaxTemp -= nTemp;
}
}
return nMax - nMaxTemp;
}
void CArchive::Write(const void* lpBuf, UINT nMax)
{
ASSERT_VALID(m_pFile);
if (nMax == 0)
return;
ASSERT(lpBuf != NULL);
ASSERT(AfxIsValidAddress(lpBuf, nMax, FALSE)); // read-only access needed
ASSERT(m_bDirectBuffer || m_lpBufStart != NULL);
ASSERT(m_bDirectBuffer || m_lpBufCur != NULL);
ASSERT(m_lpBufStart == NULL ||
AfxIsValidAddress(m_lpBufStart, m_lpBufMax - m_lpBufStart));
ASSERT(m_lpBufCur == NULL ||
AfxIsValidAddress(m_lpBufCur, m_lpBufMax - m_lpBufCur));
ASSERT(IsStoring());
// copy to buffer if possible
UINT nTemp = min(nMax, (UINT)(m_lpBufMax - m_lpBufCur));
memcpy(m_lpBufCur, lpBuf, nTemp);
m_lpBufCur += nTemp;
lpBuf = (BYTE*)lpBuf + nTemp;
nMax -= nTemp;
if (nMax > 0)
{
Flush(); // flush the full buffer
// write rest of buffer size chunks
nTemp = nMax - (nMax % m_nBufSize);
m_pFile->Write(lpBuf, nTemp);
lpBuf = (BYTE*)lpBuf + nTemp;
nMax -= nTemp;
if (m_bDirectBuffer)
{
// sync up direct mode buffer to new file position
VERIFY(m_pFile->GetBufferPtr(CFile::bufferWrite, m_nBufSize,
(void**)&m_lpBufStart, (void**)&m_lpBufMax) == (UINT)m_nBufSize);
ASSERT((UINT)m_nBufSize == (UINT)(m_lpBufMax - m_lpBufStart));
m_lpBufCur = m_lpBufStart;
}
// copy remaining to active buffer
ASSERT(nMax < (UINT)m_nBufSize);
ASSERT(m_lpBufCur == m_lpBufStart);
memcpy(m_lpBufCur, lpBuf, nMax);
m_lpBufCur += nMax;
}
}
void CArchive::Flush()
{
ASSERT_VALID(m_pFile);
ASSERT(m_bDirectBuffer || m_lpBufStart != NULL);
ASSERT(m_bDirectBuffer || m_lpBufCur != NULL);
ASSERT(m_lpBufStart == NULL ||
AfxIsValidAddress(m_lpBufStart, m_lpBufMax - m_lpBufStart, IsStoring()));
ASSERT(m_lpBufCur == NULL ||
AfxIsValidAddress(m_lpBufCur, m_lpBufMax - m_lpBufCur, IsStoring()));
if (IsLoading())
{
// unget the characters in the buffer, seek back unused amount
if (m_lpBufMax != m_lpBufCur)
m_pFile->Seek(-(m_lpBufMax - m_lpBufCur), CFile::current);
m_lpBufCur = m_lpBufMax; // empty
}
else
{
if (!m_bDirectBuffer)
{
// write out the current buffer to file
if (m_lpBufCur != m_lpBufStart)
m_pFile->Write(m_lpBufStart, m_lpBufCur - m_lpBufStart);
}
else
{
// commit current buffer
if (m_lpBufCur != m_lpBufStart)
m_pFile->GetBufferPtr(CFile::bufferCommit, m_lpBufCur - m_lpBufStart);
// get next buffer
VERIFY(m_pFile->GetBufferPtr(CFile::bufferWrite, m_nBufSize,
(void**)&m_lpBufStart, (void**)&m_lpBufMax) == (UINT)m_nBufSize);
ASSERT((UINT)m_nBufSize == (UINT)(m_lpBufMax - m_lpBufStart));
}
m_lpBufCur = m_lpBufStart;
}
}
void CArchive::FillBuffer(UINT nBytesNeeded)
{
ASSERT_VALID(m_pFile);
ASSERT(IsLoading());
ASSERT(m_bDirectBuffer || m_lpBufStart != NULL);
ASSERT(m_bDirectBuffer || m_lpBufCur != NULL);
ASSERT(nBytesNeeded > 0);
ASSERT(nBytesNeeded <= (UINT)m_nBufSize);
ASSERT(m_lpBufStart == NULL ||
AfxIsValidAddress(m_lpBufStart, m_lpBufMax - m_lpBufStart, FALSE));
ASSERT(m_lpBufCur == NULL ||
AfxIsValidAddress(m_lpBufCur, m_lpBufMax - m_lpBufCur, FALSE));
UINT nUnused = m_lpBufMax - m_lpBufCur;
ULONG nTotalNeeded = ((ULONG)nBytesNeeded) + nUnused;
// fill up the current buffer from file
if (!m_bDirectBuffer)
{
ASSERT(m_lpBufCur != NULL);
ASSERT(m_lpBufStart != NULL);
ASSERT(m_lpBufMax != NULL);
if (m_lpBufCur > m_lpBufStart)
{
// copy unused
if ((int)nUnused > 0)
{
memmove(m_lpBufStart, m_lpBufCur, nUnused);
m_lpBufCur = m_lpBufStart;
m_lpBufMax = m_lpBufStart + nUnused;
}
// read to satisfy nBytesNeeded or nLeft if possible
UINT nRead = nUnused;
UINT nLeft = m_nBufSize-nUnused;
UINT nBytes;
BYTE* lpTemp = m_lpBufStart + nUnused;
do
{
nBytes = m_pFile->Read(lpTemp, nLeft);
lpTemp = lpTemp + nBytes;
nRead += nBytes;
nLeft -= nBytes;
}
while (nBytes > 0 && nLeft > 0 && nRead < nBytesNeeded);
m_lpBufCur = m_lpBufStart;
m_lpBufMax = m_lpBufStart + nRead;
}
}
else
{
// seek to unused portion and get the buffer starting there
if (nUnused != 0)
m_pFile->Seek(-(LONG)nUnused, CFile::current);
UINT nActual = m_pFile->GetBufferPtr(CFile::bufferRead, m_nBufSize,
(void**)&m_lpBufStart, (void**)&m_lpBufMax);
ASSERT(nActual == (UINT)(m_lpBufMax - m_lpBufStart));
m_lpBufCur = m_lpBufStart;
}
// not enough data to fill request?
if ((ULONG)(m_lpBufMax - m_lpBufCur) < nTotalNeeded)
AfxThrowArchiveException(CArchiveException::endOfFile);
}
void CArchive::WriteCount(DWORD dwCount)
{
if (dwCount < 0xFFFF)
*this << (WORD)dwCount;
else
{
*this << (WORD)0xFFFF;
*this << dwCount;
}
}
DWORD CArchive::ReadCount()
{
WORD wCount;
*this >> wCount;
if (wCount != 0xFFFF)
return wCount;
DWORD dwCount;
*this >> dwCount;
return dwCount;
}
// special functions for text file input and output
void CArchive::WriteString(LPCTSTR lpsz)
{
ASSERT(AfxIsValidString(lpsz));
Write(lpsz, lstrlen(lpsz) * sizeof(TCHAR));
}
LPTSTR CArchive::ReadString(LPTSTR lpsz, UINT nMax)
{
// if nMax is negative (such a large number doesn't make sense given today's
// 2gb address space), then assume it to mean "keep the newline".
int nStop = (int)nMax < 0 ? -(int)nMax : (int)nMax;
ASSERT(AfxIsValidAddress(lpsz, (nStop+1) * sizeof(TCHAR)));
_TUCHAR ch;
int nRead = 0;
TRY
{
while (nRead < nStop)
{
*this >> ch;
// stop and end-of-line (trailing '\n' is ignored)
if (ch == '\n' || ch == '\r')
{
if (ch == '\r')
*this >> ch;
// store the newline when called with negative nMax
if ((int)nMax != nStop)
lpsz[nRead++] = ch;
break;
}
lpsz[nRead++] = ch;
}
}
CATCH(CArchiveException, e)
{
if (e->m_cause == CArchiveException::endOfFile)
{
DELETE_EXCEPTION(e);
if (nRead == 0)
return NULL;
}
else
{
THROW_LAST();
}
}
END_CATCH
lpsz[nRead] = '\0';
return lpsz;
}
BOOL CArchive::ReadString(CString& rString)
{
rString = &afxChNil; // empty string without deallocating
const int nMaxSize = 128;
LPTSTR lpsz = rString.GetBuffer(nMaxSize);
LPTSTR lpszResult;
int nLen;
for (;;)
{
lpszResult = ReadString(lpsz, (UINT)-nMaxSize); // store the newline
rString.ReleaseBuffer();
// if string is read completely or EOF
if (lpszResult == NULL ||
(nLen = lstrlen(lpsz)) < nMaxSize ||
lpsz[nLen-1] == '\n')
{
break;
}
nLen = rString.GetLength();
lpsz = rString.GetBuffer(nMaxSize + nLen) + nLen;
}
// remove '\n' from end of string if present
lpsz = rString.GetBuffer(0);
nLen = rString.GetLength();
if (nLen != 0 && lpsz[nLen-1] == '\n')
rString.GetBufferSetLength(nLen-1);
return lpszResult != NULL;
}
/////////////////////////////////////////////////////////////////////////////