从linux文件名中获取文件名前缀

int get_prefixname_from_filename(char *fileName, char *prefixName)
{

    char *tmpIn = NULL;
    char *tmpOut = NULL;
    char *tmpPointer = NULL;
    if ((NULL == fileName) || (NULL == prefixName))
    {
        printf("[%s +%d %s] (NULL == fileName) || (NULL == prefixName) failed\n", __FILE__, __LINE__, __func__);
        return -1;
    }
    //printf("[%s +%d %s] fileName=%s prefixName=%s\n", __FILE__, __LINE__, __func__, fileName, prefixName);
    tmpIn = fileName;

    if(('.' == *tmpIn) && ('/' == *(tmpIn+1)))
    {
        tmpIn = fileName + 2;
    }
    else if(('.' == *tmpIn) && ('.' == *(tmpIn+1)) && ('/' == *(tmpIn+2)))
    {
        tmpIn = fileName + 3;

    }
    else
    {
        //if(('.' == *tmpIn) && (('.' != *(tmpIn+1)) || ('/' != *(tmpIn+1))))
        if(('.' == *tmpIn) && ('.' == *(tmpIn+1)))
        {
			printf("[%s +%d %s] fileName=%s tmpIn=%s\n", __FILE__, __LINE__, __func__, fileName, tmpIn);
            printf("[%s +%d %s] ('.' == *tmpIn) && ('.' == *(tmpIn+1)) failed\n", __FILE__, __LINE__, __func__);
            return -1;
        }
        tmpIn = fileName;
    }
    tmpOut = strchr(tmpIn, '/');
    while(1)
    {
        if(NULL == tmpOut)
        {
            break;
        }
        else
        {
            tmpIn = tmpOut + 1;
            //printf("[%s +%d %s] fileName=%s tmpIn=%s\n", __FILE__, __LINE__, __func__, fileName, tmpIn);
        }        
        tmpOut = strchr(tmpIn, '/');
    }
    fileName = tmpIn;
    tmpPointer = tmpIn;
    
    while(NULL != tmpIn)
    {
        tmpOut = strchr(tmpIn, '.');
        if(NULL == tmpOut)
        {
            break;
        }
        tmpIn = tmpOut + 1;
        tmpPointer = tmpIn;
    }

    //printf("[%s +%d %s] fileName=%s tmpPointer=%s\n", __FILE__, __LINE__, __func__, fileName, tmpPointer);
    memcpy(prefixName, fileName, tmpPointer - fileName - 1);

    return 0;
}