Steuerung:
F – Reibung aus/an
Pfeil hoch – ball hinzufügen
Pfeil runter – ball wegnehmen
Pfeil rechts – fügt pro tick einen ball hinzu
Pfeil links – nimmt pro tick einen ball weg
Maus links auf ball – nimmt ball weg
Maus links auf freie Stelle – setzt ball

Das ganze läuft auf Basis von Slick 2D, einer Bibliothek für das Entwickeln von 2D-Spielen in Java. Die Bibliothek ist schön einfach zu handhaben und ermöglicht einem in kürzester Zeit ein Spiel zu entwickeln.

Ich werkel übrigens gerade an einer Netzwerkversion von Pong

(Quelltexte der Simulation)

#include <stdio.h>
#include <stdlib.h>

void func(int *i);

// harmless code
int main(void)
{
  int i = 0;
  char *buf = "pause";

  printf("i: %x;%d\n",&i,i);
  printf("buf: %x;%x;%s\n",buf,&buf,buf);

  func(&i);

  system(buf);

  return EXIT_SUCCESS;
}

// not so harmless function
void func(int *i)
{
  printf("i(dos): %x;%x\n",i,&i);

  /* To avoid system call */
  int *iptr;
  iptr = (int*) (&i - 1); // Point to the return address
  printf("iptr: %x;%x\n",iptr,*iptr);
  *iptr += 11; // change the return address (jump over the system() command)
  printf("iptr: %x;%x\n",iptr,*iptr);

  /* to inject an pwn command */
  char **cptr;
  cptr = (char**)((char*) i - sizeof(i)); // point to buf from the main func
  *cptr = "shutdown"; // point to new value
  printf("cptr: %x;%x;%s\n",cptr,*cptr,*cptr);
}

The bad part wasn’t the networkcode as you maybe think. It was the conversion of the char array I used as buffer. I searched for functions that would do exactly this, but the result was equal zero.
So I deceided to write them myself.

Here is the result, I hope you find it useful:

/*
  Author: Michael Henke
  Date:   19 May 2009

  These two functions show how to convert an integer to a chararray and vice versa.

*/

#include <stdio.h>
#include <stdlib.h>

// Puts the Stringrepresentation of $var into the buffer $buf
// $buf -> after the function here is the stringrepresentation of $var
// $var -> the integer that is going to be interpreted as String
void getString(unsigned char* buf,unsigned int var)
{
  unsigned int test;
  char i;

  test = 0x000000FF;
  for(i=3;i>=0;i--)
  {
    buf[i] = var & test;
    var >>= 8;
  }
}

// Gets the Integerrepresentation of the String $buf
// $buf -> the string that is interpreted
// return -> the integerrepresentation of $buf
void getUInt(unsigned int* var,unsigned char* buf)
{
  char i;

  *var = 0;
  for(i=0;i<4;i++)
  {
    *var <<= 8;
    *var |= buf[i];
  }
}

int main(void)
{
  unsigned int var = 0x2CFA207A;
  unsigned char buf[4] = {0,0,0,0};

  printf("Hex: 0x%x\n",var);
  getString(buf,var);
  var = 0;
  fputs("--------------\n",stdout);
  getUInt(&var,buf);
  printf("Hex again: 0x%x\n",var);

  return EXIT_SUCCESS;
}

Der beep-o-mat liest eine Textdatei aus und erzeugt basierend auf einer zeilenbasierenden Syntax Töne/Beeps.

/**************************\
| Autor: Michael Henke     |
| Datum: 02.11.2009        |
\**************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef __WIN32__
  #include <windows.h>
#elif __unix__
  #include <fcntl.h>
  #include <signal.h>
  #include <linux/kd.h>
#endif
#define MAXLEN 50
#define SLEEP "sleep"

void parsebeep(char *line);
void die(char *mesg,int code);

#ifdef __unix__
void Beep(int freq,int len);
void handle_signal(int signum);
int console_fd = -1;
#endif

int main(int argc,char **argv)
{
  FILE* file;
  char line[MAXLEN];

  if(argc!=2)
  {
    die("Usage: beep-o-mat file\n",0);
  }

  file = fopen(argv[1],"r");
  if(!file)
  {
    die("File opening was not successfull!\n",1);
  }

  #ifdef __unix__
  signal(SIGINT, handle_signal);
  #endif

  for(;fgets(line,MAXLEN,file)!=NULL;)
  {
    parsebeep(line);
  }

  return EXIT_SUCCESS;
}

void parsebeep(char *line)
{
  int freq,dur;
  char *ptr;

  line[strlen(line)-1] = '\0';   // cut the newline
  ptr = strchr(line,(int)':');     // get pointer to the first colon in the line
  if (ptr==NULL)
  {
    return;
  }
  *ptr = '\0';                     // set the stringend where the colon  was -> line = frequency
  ptr = ptr+1;                       // point to the sign after the colon  -> a = duration

  dur = atoi(ptr);
  if (strcmp(line,SLEEP)==0)
  {
    printf("%s:%d\n",SLEEP,dur);
    #ifdef __WIN32__
    Sleep(dur);
    #elif __unix__
    usleep(dur*1000);
    #endif
  }
  else
  {
    freq = atoi(line);
    printf("%d:%d\n",freq,dur);
    Beep(freq,dur);
  }
}

void die(char *mesg,int code)
{
  fputs(mesg,stderr);
  exit(code);
}

#ifdef __unix__
void Beep(int freq,int len)
{
  if((console_fd = open("/dev/console", O_WRONLY)) == -1)
  {
    die("Could not open /dev/console for writing.\n",1);
  }

  if(ioctl(console_fd, KIOCSOUND, (int)(1193180/freq)) < 0)
  {
    die("Could not beep.\n",1);
  }

  usleep(1000*len);
  ioctl(console_fd, KIOCSOUND, 0);
  close(console_fd);
}

void handle_signal(int signum) {
  switch(signum) {
  case SIGINT:
    if(console_fd >= 0) {
      ioctl(console_fd, KIOCSOUND, 0);
      close(console_fd);
      exit(signum);
    } else {
      exit(signum);
    }
  }
}
#endif

Wer einen eigenen Beep-Song erstellen will, dem wird diese Seite wahrscheinlich sehr helfen.

Hier ein Archiv mit Liedern die ich im Internet zusammen gesammelt habe, enthalten sind:

Star Wars – Imperial March
Still Alive
axelf
merry christmas
Amazing grace
black sabbath – crazy train intro
Canon in D Johann Pachellbel
charlie brown
Cold Play – Clocks
daoremon
Ludwig van Beethoven – Für Elise
Flight of the Bumblebee
Harvester of Sorrow
i like to move it move it
Mario1
mario underwater
Mary has a little lamb
Scott Joplin – The Entertainer
Super Mario bros. 3
supermario bros
Tetris
Led Zeppelin – Fool In The Rain
How To Save a Life
Deck the Halls

Viel Spass

Ach, und nicht vergessen die Piraten zu wählen
Wikipedia – Piratenpartei Deutschland
Website der Piratenpartei Deutschland