diff options
Diffstat (limited to 'ncurses-5.9/ncurses/base/lib_scroll.c')
-rw-r--r-- | ncurses-5.9/ncurses/base/lib_scroll.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/ncurses-5.9/ncurses/base/lib_scroll.c b/ncurses-5.9/ncurses/base/lib_scroll.c new file mode 100644 index 0000000..c2f6a36 --- /dev/null +++ b/ncurses-5.9/ncurses/base/lib_scroll.c @@ -0,0 +1,150 @@ +/**************************************************************************** + * Copyright (c) 1998-2009,2010 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: Thomas E. Dickey 1996-2003 * + * and: 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("$Id$") + +NCURSES_EXPORT(void) +_nc_scroll_window(WINDOW *win, + int const n, + NCURSES_SIZE_T const top, + NCURSES_SIZE_T const bottom, + NCURSES_CH_T blank) +{ + int limit; + int line; + int j; + size_t to_copy = (sizeof(NCURSES_CH_T) * (size_t) (win->_maxx + 1)); + + TR(TRACE_MOVE, ("_nc_scroll_window(%p, %d, %ld, %ld)", + (void *) win, n, (long) top, (long) bottom)); + + if (top < 0 + || bottom < top + || bottom > win->_maxy) { + TR(TRACE_MOVE, ("nothing to scroll")); + return; + } + + /* + * 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) { + limit = top - n; + for (line = bottom; line >= limit && line >= 0; line--) { + TR(TRACE_MOVE, ("...copying %d to %d", line + 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 < limit && line <= win->_maxy; line++) { + TR(TRACE_MOVE, ("...filling %d", 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) { + limit = bottom - n; + for (line = top; line <= limit && line <= win->_maxy; 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 > limit && line >= 0; 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); + + if_WIDEC({ + if (WINDOW_EXT(win, addch_used) != 0) { + int next = WINDOW_EXT(win, addch_y) + n; + if (next < 0 || next > win->_maxy) { + TR(TRACE_VIRTPUT, + ("Alert discarded multibyte on scroll")); + WINDOW_EXT(win, addch_y) = 0; + } else { + TR(TRACE_VIRTPUT, ("scrolled working position to %d,%d", + WINDOW_EXT(win, addch_y), + WINDOW_EXT(win, addch_x))); + WINDOW_EXT(win, addch_y) = next; + } + } + }) +} + +NCURSES_EXPORT(int) +wscrl(WINDOW *win, int n) +{ + T((T_CALLED("wscrl(%p,%d)"), (void *) win, n)); + + if (!win || !win->_scroll) { + TR(TRACE_MOVE, ("...scrollok is false")); + returnCode(ERR); + } + + if (n != 0) { + _nc_scroll_window(win, n, win->_regtop, win->_regbottom, win->_nc_bkgd); + _nc_synchook(win); + } + returnCode(OK); +} |