讀取配置文件的類

//author Naven 2003 for both Win32 and Unix os

class MyProperties {
public:
    MyProperties();
    MyProperties(istream &is); 
    MyProperties(const string &filename); 

    void load(const string &filename);
    unsigned long size(); 
    string filename();
    string get(const string &name, const string &default_value); 
    void remove(const string &name); 
    void set(const string &name, const string &value); 
    void add(const string &name, const string &value); 
    string getName(const int &i);
    string getValue(const int &i);

    void save();
    void save(string &filename); 

private:
    void init(istream &is); 

private:
    string _file; 
    vector _vals, _elms; 
    unsigned long _size; 

}; 

MyProperties::MyProperties()
{
    _size = 0;
}

MyProperties::MyProperties(istream &is) 
{
    _size = 0;
    init(is); 
}

MyProperties::MyProperties(const string &filename) 
{
    load(filename); 
}

void
MyProperties::load(const string &filename) 
{
    _elms.clear(); _vals.clear(); 
    _size = 0; 
    if(filename.empty()) 
        return; 
    ifstream is(filename.c_str()); 
    _file = filename; 

    init(is); 
}

void 
MyProperties::init(istream &is) 
{
    if(!is) return;
    char ln[LINE_SIZE+1], *pval; 
    _elms.clear(); _vals.clear(); 
    _size = 0; 
    while(is.getline(ln, LINE_SIZE)) { 
        trimleft(ln); 
        if(ln[0] != '#' && (pval = strchr(ln, '=')) != NULL) {
            pval[0] = 0; pval++; 
            trimright(ln); trim(pval); 
            if(ln[0] != 0 && pval[0] != 0) { 
                _elms.push_back(ln); 
                _vals.push_back(pval);
                _size ++; 
            }
        }
    }
}

unsigned long 
MyProperties::size() 
{
    return _size;
}

string
MyProperties::filename()
{
    return _file; 
}

string 
MyProperties::getName(const int &i)
{
    if(i >=0 && i<_elms.size()) 
        return _elms[i];
    return "";
}

string 
MyProperties::getValue(const int &i)
{
    if(i >=0 && i<_vals.size()) 
        return _vals[i];
    return "";
}

string
MyProperties::get(const string &name, const string &default_value="") 
{
    if(name.empty()) 
        return default_value; 
    vector::const_iterator elm_iter = _elms.begin(), elm_end = _elms.end();
    vector::const_iterator val_iter = _vals.begin(), val_end = _elms.end();
    while(elm_iter != elm_end && val_iter != val_end) {
        if((*elm_iter) == name) 
            return *val_iter; 
        elm_iter ++; 
        val_iter ++; 
    }
    return default_value; 
}

void
MyProperties::remove(const string &name) 
{
    if(name.empty()) return;
    vector::iterator elm_iter = _elms.begin(), elm_end = _elms.end();
    vector::iterator val_iter = _vals.begin(), val_end = _elms.end();
    while(elm_iter != elm_end && val_iter != val_end) {
        if((*elm_iter) == name) {
            _elms.erase(elm_iter); 
            _vals.erase(val_iter); 
            _size --;
        } 
        elm_iter ++; 
        val_iter ++; 
    }
}

void
MyProperties::set(const string &name, const string &value) 
{
    if(name.empty()) return;
    vector::iterator elm_iter = _elms.begin(), elm_end = _elms.end();
    vector::iterator val_iter = _vals.begin(), val_end = _elms.end();
    while(elm_iter != elm_end && val_iter != val_end) {
        if((*elm_iter) == name) 
            *val_iter = value; 
        elm_iter ++; 
        val_iter ++; 
    }
}

void 
MyProperties::add(const string &name, const string &value) 
{
    if(name.empty()) return; 
    _elms.push_back(name); _vals.push_back(value); 
    _size ++; 
}

void 
MyProperties::save(string &filename)
{
    if(filename.empty()) 
        return;
    ifstream is(filename.c_str()); 
    if(!is) return; 
    
    char ln[LINE_SIZE+1], *pval; 
    ostrstream sbuf; string str, str2; bool exist_flag;
    vector vec; 

    while(is.getline(ln, LINE_SIZE)) { 
        str = ln; trimleft(ln); exist_flag = false;
        if(ln[0] != '#' && (pval = strchr(ln, '=')) != NULL) {
            pval[0] = 0; trimright(ln); 
            if(ln[0] != 0 && !(str2=get(ln)).empty()) {
                sbuf << ln << "=" << str2 << endl;
                vec.push_back(ln); 
                exist_flag = true; 
            }
        }
        if(exist_flag == false) 
            sbuf << str << endl; 
    }

    vector::iterator elm_iter = _elms.begin(), elm_end = _elms.end();
    vector::iterator val_iter = _vals.begin(), val_end = _elms.end();
    vector::iterator vec_iter, vec_end = vec.end();
    while(elm_iter != elm_end && val_iter != val_end) {
        vec_iter = vec.begin(); exist_flag = false;
        while(vec_iter != vec_end) {
            if((*vec_iter) == (*elm_iter)) {
                exist_flag = true; break; 
            } 
            vec_iter ++; 
        } 
        if(exist_flag == false) 
            sbuf << *elm_iter << "=" << *val_iter << endl; 
        elm_iter ++; val_iter ++; 
    } 
    sbuf << ends;
    
    ofstream os(filename.c_str()); 
    if(os) os << sbuf.str();
}

void 
MyProperties::save()
{
    save(_file);
}

/* trim the space and tab at left */
char*
trimleft( char *s )
{
    register int i=0; int sl=0;
    char *sc =0;

    if( s == NULL || s[0] == 0 ) return NULL;
    sl = strlen( s );

    /* trim space and tab char at the left */
    for( i=0; i s )
    {
        sl = strlen(sc);
        for( i=0; i=0; i-- )
    {
        /* 32 is space, 9 is tab */
        if( s[i] == 32 || s[i] == 9 )
            s[i] = 0;
        else
            break;
    }
    return s;
}

/* trim space and tab at left and right */
char*
trim( char *s )
{
    if( s == NULL || s[0] == 0 ) return NULL;

    trimright( s );
    trimleft( s );

    return s;
}