diff options
Diffstat (limited to 'contrib/ncurses/ncurses/base/lib_scroll.c')
-rw-r--r-- | contrib/ncurses/ncurses/base/lib_scroll.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/contrib/ncurses/ncurses/base/lib_scroll.c b/contrib/ncurses/ncurses/base/lib_scroll.c new file mode 100644 index 000000000000..197bb221a07c --- /dev/null +++ b/contrib/ncurses/ncurses/base/lib_scroll.c @@ -0,0 +1,118 @@ +/**************************************************************************** + * Copyright (c) 1998 Free Software Foundation, Inc. * + * * + * Permission is hereby granted, free of charge, to any person obtaining a * + * copy of this software and associated documentation files (the * + * "Software"), to deal in the Software without restriction, including * + * without limitation the rights to use, copy, modify, merge, publish, * + * distribute, distribute with modifications, sublicense, and/or sell * + * copies of the Software, and to permit persons to whom the Software is * + * furnished to do so, subject to the following conditions: * + * * + * The above copyright notice and this permission notice shall be included * + * in all copies or substantial portions of the Software. * + * * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * + * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * + * THE USE OR OTHER DEALINGS IN THE SOFTWARE. * + * * + * Except as contained in this notice, the name(s) of the above copyright * + * holders shall not be used in advertising or otherwise to promote the * + * sale, use or other dealings in this Software without prior written * + * authorization. * + ****************************************************************************/ + +/**************************************************************************** + * Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 * + * and: Eric S. Raymond <esr@snark.thyrsus.com> * + ****************************************************************************/ + + + +/* +** lib_scroll.c +** +** The routine wscrl(win, n). +** positive n scroll the window up (ie. move lines down) +** negative n scroll the window down (ie. move lines up) +** +*/ + +#include <curses.priv.h> + +MODULE_ID("$Id: lib_scroll.c,v 1.16 1998/02/11 12:13:55 tom Exp $") + +void _nc_scroll_window(WINDOW *win, int const n, short const top, short const bottom, chtype blank) +{ +int line, j; +size_t to_copy = (size_t)(sizeof(chtype) * (win->_maxx + 1)); + + TR(TRACE_MOVE, ("_nc_scroll_window(%p, %d, %d, %d)", win, n, top,bottom)); + + /* + * This used to do a line-text pointer-shuffle instead of text copies. + * That (a) doesn't work when the window is derived and doesn't have + * its own storage, (b) doesn't save you a lot on modern machines + * anyway. Your typical memcpy implementations are coded in + * assembler using a tight BLT loop; for the size of copies we're + * talking here, the total execution time is dominated by the one-time + * setup cost. So there is no point in trying to be excessively + * clever -- esr. + */ + + /* shift n lines downwards */ + if (n < 0) { + for (line = bottom; line >= top-n; line--) { + memcpy(win->_line[line].text, + win->_line[line+n].text, + to_copy); + if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line+n].oldindex); + } + for (line = top; line < top-n; line++) { + for (j = 0; j <= win->_maxx; j ++) + win->_line[line].text[j] = blank; + if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX); + } + } + + /* shift n lines upwards */ + if (n > 0) { + for (line = top; line <= bottom-n; line++) { + memcpy(win->_line[line].text, + win->_line[line+n].text, + to_copy); + if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line+n].oldindex); + } + for (line = bottom; line > bottom-n; line--) { + for (j = 0; j <= win->_maxx; j ++) + win->_line[line].text[j] = blank; + if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX); + } + } + touchline(win, top, bottom-top+1); +} + +int +wscrl(WINDOW *win, int n) +{ + T((T_CALLED("wscrl(%p,%d)"), win, n)); + + if (!win || !win->_scroll) + returnCode(ERR); + + if (n == 0) + returnCode(OK); + + if ((n > (win->_regbottom - win->_regtop)) || + (-n > (win->_regbottom - win->_regtop))) + returnCode(ERR); + + _nc_scroll_window(win, n, win->_regtop, win->_regbottom, _nc_background(win)); + + _nc_synchook(win); + returnCode(OK); +} |