editordrawrows.c

void editorDrawRows(struct abuf *ab) {
  int y;
  for (y = 0; y < E.screenrows; y++) {
    int filerow = y + E.rowoff;
    if (filerow >= E.numrows) {
      if (E.numrows == 0 && y == E.screenrows / 3) {
        char welcome[80];
        int welcomelen = snprintf(welcome, sizeof(welcome),
                                  "Bob, the text editor");
        if (welcomelen > E.screencols) welcomelen = E.screencols;
        int padding = (E.screencols - welcomelen) / 2;
        if (padding) {
          abAppend(ab, " ", 1);
          padding--;
        }
        while (padding--) abAppend(ab, " ", 1);
        abAppend(ab, welcome, welcomelen);
      } else {
        abAppend(ab, " ", 1);
      }
    } else {
      int len = E.row[filerow].rsize - E.coloff;
      if (len < 0) len = 0;
      if (len > E.screencols) len = E.screencols;
      abAppend(ab, &E.row[filerow].render[E.coloff], len);
    }
    abAppend(ab, "\x1b[K", 3);
    abAppend(ab, "\r\n", 2);
  }
}