Linux C下fdopen的问题__m_fdIndex_bRet_m_nIndex_m_fStream_m_nLineCount_

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Linux C下fdopen的问题

来源: 互联网发布时间：2016-10-12

本文导语: void LogManage::GetIndex(void) { if(!m_bOpen) { ReadIndex(); } printf("Current log file: [%s] n", m_ppFileList[m_nIndex]); } void LogManage::Clean() { Close(); for(int i = 0; i = 50) { WriteIndex(); } fputc('n', m_fStream); if(m_nLineCount >= MAX_LINE_COU...

void LogManage::GetIndex(void)
{
if(!m_bOpen)
{
ReadIndex();
}
printf("Current log file: [%s] n", m_ppFileList[m_nIndex]);
}
void LogManage::Clean()
{
Close();
for(int i = 0; i = 50)
{
WriteIndex();
}
fputc('n', m_fStream);
if(m_nLineCount >= MAX_LINE_COUNT)
{
close(m_fdLog);
// fclose(m_fStream);
m_nIndex = (m_nIndex + 1) % FILE_COUNT;
m_fdLog = open(m_ppFileList[m_nIndex], O_CREAT | O_TRUNC | O_WRONLY, 0666);
if(-1 == m_fdLog)
{
printf("open file failed! Line: %dn", __LINE__);
}
m_nLineCount = 0;

/* why NOT work??????
* m_fStream = fdopen(m_fdLog, "a+"); // "a+" means append
if(NULL == m_fStream)
{
printf("fdopen failed! Line: %dn", __LINE__);
}
*/

/*              why NOT work?????
char pBuf[100];
sprintf(pBuf, "nnn*******************************   %d    *****************nnn", m_nLogTimer); // Indicate the file sequence
fputs(pBuf, m_fStream);
fflush(m_fStream);
*/ fprintf(m_fStream, "nnn*******************************   %d    *****************nnn", m_nLogTimer); // Indicate the file sequence
fflush(m_fStream);

WriteIndex();
}
fflush(m_fStream);
fdatasync(m_fdLog);
}

bool LogManage::WriteIndex(void)
{
m_fdIndex = open(m_pIndexFile, O_RDWR);
if(-1 == m_fdIndex) // open fail, maybe haven't been created
{
printf("Index file %s dose NOT exists! n", m_pIndexFile);
return false;
}
else // open successfully
{
bool bRet = true;
lseek(m_fdIndex, 0, SEEK_SET);
bRet = bRet && (-1 != write(m_fdIndex, &m_nIndex, sizeof(m_nIndex))); // write  m_nIndex
bRet = bRet && (-1 != write(m_fdIndex, &m_nLineCount, sizeof(m_nLineCount))); // write  m_nLineCount
bRet = bRet && (-1 != write(m_fdIndex, &m_nLogTimer, sizeof(m_nLogTimer))); // write  m_nLogTimer
fdatasync(m_fdIndex);
bRet = bRet && (-1 != close(m_fdIndex)); // close index file
return bRet;
}
}

bool LogManage::ReadIndex(void)
{
bool bRet = true;
m_fdIndex = open(m_pIndexFile, O_RDWR);
if(-1 == m_fdIndex) // open fail, maybe haven't been created
{
printf("Index file %s dose NOT exists! Create it!n", m_pIndexFile);
m_fdIndex = open(m_pIndexFile, O_CREAT | O_RDWR, 0666);
if(-1 == m_fdIndex)
{
error("Create index file %s FAILED! Errno: %d", m_pIndexFile, errno);
bRet = false;
}
else
{
int nTemp = 0;
bRet = bRet && (-1 != write(m_fdIndex, &nTemp, sizeof(m_nIndex)));
bRet = bRet && (-1 != write(m_fdIndex, &nTemp, sizeof(m_nLineCount)));
bRet = bRet && (-1 != write(m_fdIndex, &nTemp, sizeof(m_nLogTimer)));
fdatasync(m_fdIndex);
m_nIndex = 0;
m_nLineCount = 0;
m_nLogTimer = 0;
}
}
else // open successfully
{
lseek(m_fdIndex, 0, SEEK_SET);
if(read(m_fdIndex, &m_nIndex, sizeof(m_nIndex))