Stack problems

#include <stdlib.h>
#include <string.h>

#define WIN_MAXTEXT         128
#define WIN_TEXTLEN         21

typedef struct {
  int count;
  int top;
  char caption[WIN_TEXTLEN+1];
  char lines[WIN_MAXTEXT][WIN_TEXTLEN+1];
} WIN_TEXT;

static WIN_TEXT win_text;
static char *line = "Hello World";

void
main(void)
{
  WIN_TEXT *text;
  char *s,*d;
  int i;

  text = &win_text;
  if ( text->count<WIN_MAXTEXT ) {
    d = text->lines[text->count++];
    s = line;
    for ( i=0 ; *s && i<WIN_TEXTLEN ; i++ )
      *(d++) = *(s++);
    *d = '\0';
  }
}