StrTok.cxx

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// StrTok.cpp: implementation of the CStrTok class.
//

#include "StrTok.h"
#include "string.h"

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

// Construction/Destruction

CStrTok::CStrTok()
{
        m_bDelimiterAsToken = m_bOneByOneDelimiter = m_bDelimitersInSequence = false;
        m_chDelimiter = 0;
        m_lpszNext = NULL;
}

CStrTok::~CStrTok()
{

}

char* CStrTok::GetFirst(char* lpsz, const char* lpcszDelimiters)
{
        Break();

        m_lpszNext = lpsz;
        return GetNext(lpcszDelimiters); 
}

char* CStrTok::GetNext(const char* lpcszDelimiters)
{
        if(m_lpszNext == NULL)
                return NULL;

        // return the saved delimiter
        if(m_chDelimiter != 0)
                *m_lpszNext = m_chDelimiter;

        char* lpsz = m_lpszNext;
        if(m_bDelimiterAsToken)
                // increment the next pointer to the next delimiter or token
                if(m_bDelimitersInSequence)
                {
                        int nLength = strlen(lpcszDelimiters);
                        if(memcmp(lpcszDelimiters, m_lpszNext, nLength) == 0)
                                m_lpszNext += nLength;
                        else
                                m_lpszNext = strstr(m_lpszNext, lpcszDelimiters); // may be NULL
                }
                else
                {
                        if(strchr(lpcszDelimiters, *m_lpszNext))
                                m_lpszNext++;
                        else
                                m_lpszNext += strcspn(m_lpszNext, lpcszDelimiters);
                }
        else
                if(m_bDelimitersInSequence)
                {
                        int nLength = strlen(lpcszDelimiters);
                        // increment the token pointer
                        while(memcmp(lpcszDelimiters, lpsz, nLength) == 0)
                        {
                                lpsz += nLength;
                                if(m_bOneByOneDelimiter)
                                        break;
                        }
                        // increment the next pointer after the end of the token
                        m_lpszNext = strstr(lpsz, lpcszDelimiters); // may be NULL
                }
                else
                {
                        // increment the token pointer to the start of the token
                        if(!m_bOneByOneDelimiter)
                                lpsz += strspn(lpsz, lpcszDelimiters);
                        else
                                if(strchr(lpcszDelimiters, *lpsz) && m_chDelimiter)
                                        lpsz++;
                        // increment the next pointer after the end of the token
                        m_lpszNext = lpsz + strcspn(lpsz, lpcszDelimiters);
                }
        
        if(m_lpszNext == NULL || *m_lpszNext == 0)
        {       // reach the end of the buffer
                m_chDelimiter = 0;
                m_lpszNext = NULL;
        }
        else
        {       // save the delimiter and terminate the token by null
                m_chDelimiter = *m_lpszNext;
                *m_lpszNext = 0;
        }
        if(*lpsz == 0 && !m_bOneByOneDelimiter)
                return NULL;
        return lpsz;
}

void CStrTok::SetNext(const char* lpcszNext)
{
        if(m_chDelimiter != 0)
                *m_lpszNext = m_chDelimiter;
        m_chDelimiter = 0;
        m_lpszNext = (char*)lpcszNext;
}

bool CStrTok::IsEOB()
{
        return m_lpszNext == NULL;
}

bool CStrTok::IsDelimiter(char ch, const char* lpcszDelimiters)
{
        return strchr(lpcszDelimiters, ch) != NULL;
}

void CStrTok::Break()
{
        SetNext(NULL);
}

void CStrTok::TrimLeft(char* &lpsz, const char* lpcszDelimiters /*= NULL*/)
{
        if(m_lpszNext == NULL)
                return;
        if(lpcszDelimiters == NULL)
                lpcszDelimiters = " \t\r\n";
        while(strchr(lpcszDelimiters, *lpsz))
                lpsz++;
}

void CStrTok::TrimRight(const char* lpcszDelimiters /*= NULL*/)
{
        if(m_lpszNext == NULL)
                return;
        if(lpcszDelimiters == NULL)
                lpcszDelimiters = " \t\r\n";
        char* pNext = m_lpszNext-1;
        while(strchr(lpcszDelimiters, *pNext))
                *pNext = 0, pNext--;
}