музыкальный плеер, ревизия кода, советы и

#include <iostream>
#include <string>
#include <cstdlib>
 
using namespace std;
 
const string STRING_MASK_SET_VOLUME = "-s_v";
const string STRING_MASK_PAUSE      = "-p";
const string STRING_MASK_LOAD       = "-ld";
const string STRING_MASK_PLAY       = "-pl";
const string STRING_MASK_QUIT       = "-halt";
 
enum Main_cmd_ID
{
    MCMD_UNKNOWN    = 0,
    MCMD_LOAD       = 1,
    MCMD_PLAY       = 2,
    MCMD_SET_VOLUME = 3,
    MCMD_PAUSE      = 4,
    MCMD_QUIT       = 5
};
 
typedef void (*MainFunctions)(char *);
 
 
struct MainCmd
{
    Main_cmd_ID id;
    char* params;
 
    MainCmd()
    {
        id = MCMD_UNKNOWN;
        params = NULL;
    }
 
    ~MainCmd()
    {
        delete params;
    }
};
// ---------------------------------------------------
 
bool on_cycle = true;
// ---------------------------------------------------
 
void unknown(char*);
void load(char*);
void play(char*);
void set_volume(char*);
void pause(char*);
void quit(char*);
 
MainFunctions main_function[6] = { unknown,
                                    load,
                                    play,
                                    set_volume, 
                                    pause,
                                    quit
};
 
// ---------------------------------------------------
MainCmd parse_cmd(string);
// ---------------------------------------------------
int main()
{
    string cmd_line = "";
 
    while(on_cycle)
    {
        MainCmd cur_cmd;
        getline(cin, cmd_line);
        cur_cmd = parse_cmd(cmd_line);
 
        main_function[cur_cmd.id](cur_cmd.params);
    }
 
    return 0;
}
// ----------------------------------------------------
void unknown(char* params)
{
    string s_param = (params == NULL) ? "" : string(params);
    cout << "cmd : unknown\nparams : " << s_param << endl;
}
 
void load(char* params)
{
    string s_param = (params == NULL) ? "" : string(params);
    cout << "cmd : load\nparams :" << s_param << endl;
}
 
void play(char* params)
{
    string s_param = (params == NULL) ? "" : string(params);
    cout << "cmd : play\nparams :" << s_param << endl;
}
 
void set_volume(char* params)
{
    string s_param = (params == NULL) ? "" : string(params);
    cout << "cmd : set_volume\nparams :" << s_param << endl;
}
 
void pause(char* params)
{
    string s_param = (params == NULL) ? "" : string(params);
    cout << "cmd : pause\nparams :" << s_param << endl;
}
 
void quit(char* params)
{
    //string s_param = (params == NULL) ? "" : string(params);
    //cout << "cmd : quit\nparams :" << s_param << endl;
    on_cycle = false;
}
//------------------------------------------------------
 
MainCmd parse_cmd(string line)
{
    MainCmd res;
    string cmd_line_id = "";
    string cmd_line_params = "";
    char *p;
 
    if(line.find("-") == string::npos)
    {
        res.id = MCMD_UNKNOWN;
 
        return res;
    } else 
    {
        size_t len = line.find("-");
 
        if(len)
            line.erase(line.begin()+len);
        
        cmd_line_id = (line.find(" ") != string::npos) ? line.substr(0, line.find(" ")) : line;
        cmd_line_params = (line.find(" ") != string::npos) ? line.substr(line.find(" ") + 1) : "";
 
        if(cmd_line_params.size())
        {
            p = new char[cmd_line_params.size()];
            strcpy(p, cmd_line_params.c_str());
        }
    }
 
    res.id = (cmd_line_id == STRING_MASK_LOAD) ? MCMD_LOAD :
                (cmd_line_id == STRING_MASK_PLAY) ? MCMD_PLAY :
                (cmd_line_id == STRING_MASK_SET_VOLUME) ? MCMD_SET_VOLUME :
                (cmd_line_id == STRING_MASK_PAUSE) ? MCMD_PAUSE : 
                (cmd_line_id == STRING_MASK_QUIT) ? MCMD_QUIT : MCMD_UNKNOWN;
    
    res.params = p;
 
    return res; 
}