SPO-4-NIX-FINAL

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <ncurses.h>
#include <errno.h>
#include <cstring>

#define MAX_THREAD_NUMBER 10

void* writer( void* );
void removeAll();
int addThread();
int removeThread();
pthread_mutex_t mu;
int quitThread[MAX_THREAD_NUMBER];
int currentThreadCount = 0;
pthread_t handle[MAX_THREAD_NUMBER];

void init()
{
    initscr();
    clear();
    noecho();
    refresh();
    curs_set(0);
    pthread_mutex_init(&mu, NULL);
}

int main()
{
    init();
    int isQuit = 0;
    while(isQuit == 0)
    {
        fflush(stdin);
        char c = getch();
        switch ( c )
        {
            case '+':
                addThread();
                break;
            case '-':
                removeThread();
                break;
            case 'q':
                isQuit = 1;
                break;
            default:
                break;
        }
    }
    removeAll();
    pthread_mutex_destroy(&mu);
    echo();
    endwin();
    return 0;
}

int removeThread()
{
    if(currentThreadCount != 0)
    {
        quitThread[--currentThreadCount] = 1;
        if (pthread_join(handle[currentThreadCount], NULL) != 0)
        {
            printw("pthread_join(%lu) failed with error %s\n", handle[currentThreadCount] ,strerror(errno));
            refresh();
        }
    }
    return 0;
}

int addThread()
{
    if ( currentThreadCount < MAX_THREAD_NUMBER)
    {
        quitThread[currentThreadCount] = 0;
        if (pthread_create(&handle[currentThreadCount], NULL, writer, (void*)currentThreadCount) != 0)
        {
            printw("pthread_create() failed with error %s\n", strerror(errno));
            refresh();
            return 1;
        }
        else
        {
            currentThreadCount++;
        }
    }
    return 0;
}

void removeAll()
{
    while( currentThreadCount > 0 )
    {
        quitThread[--currentThreadCount] = 1;
        if (pthread_join(handle[currentThreadCount], 0) != 0)
        {
            printw("pthread_join(%lu) failed with error %s\n", handle[currentThreadCount], strerror(errno));
            refresh();
        }
    }
}

char textStrings[MAX_THREAD_NUMBER][50] =
    {
        "0-Nirvana ",
        "1-Queen ",
        "2-Scorpions ",
        "3-Metallica ",
        "4-Bon Jovi ",
        "5-The Final Countdown ",
        "6-Rammstein ",
        "7-Louna ",
        "8-Sonic Syndicate ",
        "9-Skillet "
    };


void* writer(void* param)
{
    int a = (int)param;
    while(quitThread[a] != 1)
    {
        if (pthread_mutex_trylock(&mu) == 0)
        {
            for (int i = 0; textStrings[a][i]; i++)
            {
                printw("%c", textStrings[a][i]);
                refresh();
                usleep(100000);
            }
            printw(" ");
            refresh();
            pthread_mutex_unlock(&mu);
        }
    }
    quitThread[a] = 0;
}