/*************************************************************************** * COPYRIGHT NOTICE * **************************************************************************** * ncurses is copyright (C) 1992-1995 * * Zeyd M. Ben-Halim * * zmbenhal@netcom.com * * Eric S. Raymond * * esr@snark.thyrsus.com * * * * Permission is hereby granted to reproduce and distribute ncurses * * by any means and for any fee, whether alone or as part of a * * larger distribution, in source or in binary form, PROVIDED * * this notice is included with any such distribution, and is not * * removed from any of its header files. Mention of ncurses in any * * applications linked with it is highly appreciated. * * * * ncurses comes AS IS with no warranty, implied or expressed. * * * ***************************************************************************/ /*----------------------------------------------------------------- * * lib_doupdate.c * * The routine doupdate() and its dependents. Also _nc_outstr(), * so all physical output is concentrated here (except _nc_outch() * in lib_tputs.c). * *-----------------------------------------------------------------*/ #include #if defined(TRACE) && HAVE_SYS_TIMES_H && HAVE_TIMES #define USE_TRACE_TIMES 1 #else #define USE_TRACE_TIMES 0 #endif #if HAVE_SYS_TIME_H && ! SYSTEM_LOOKS_LIKE_SCO #include #endif #if USE_TRACE_TIMES #include #endif #if USE_FUNC_POLL #include #include #elif HAVE_SELECT #if HAVE_SYS_SELECT_H #include #endif #endif #include MODULE_ID("$Id: lib_doupdate.c,v 1.60 1997/05/03 19:32:55 Alexander.V.Lukyanov Exp $") /* * This define controls the line-breakout optimization. Every once in a * while during screen refresh, we want to check for input and abort the * update if there's some waiting. CHECK_INTERVAL controls the number of * changed lines to be emitted between input checks. * * Note: Input-check-and-abort is no longer done if the screen is being * updated from scratch. This is a feature, not a bug. */ #define CHECK_INTERVAL 6 /* * Enable checking to see if doupdate and friends are tracking the true * cursor position correctly. NOTE: this is a debugging hack which will * work ONLY on ANSI-compatible terminals! */ /* #define POSITION_DEBUG */ static inline chtype ClrBlank ( WINDOW *win ); static inline chtype ClrSetup ( WINDOW *scr ); static int ClrBottom(int total); static int InsStr( chtype *line, int count ); static void ClearScreen( void ); static void ClrUpdate( WINDOW *scr ); static void DelChar( int count ); static void TransformLine( int const lineno ); #ifdef POSITION_DEBUG /**************************************************************************** * * Debugging code. Only works on ANSI-standard terminals. * ****************************************************************************/ void position_check(int expected_y, int expected_x, char *legend) /* check to see if the real cursor position matches the virtual */ { static char buf[9]; int y, x; if (_nc_tracing) return; memset(buf, '\0', sizeof(buf)); (void) write(1, "\033[6n", 4); /* only works on ANSI-compatibles */ (void) read(0, (void *)buf, 8); _tracef("probe returned %s", _nc_visbuf(buf)); /* try to interpret as a position report */ if (sscanf(buf, "\033[%d;%dR", &y, &x) != 2) _tracef("position probe failed in %s", legend); else if (y - 1 != expected_y || x - 1 != expected_x) _tracef("position seen (%d, %d) doesn't match expected one (%d, %d) in %s", y-1, x-1, expected_y, expected_x, legend); else _tracef("position matches OK in %s", legend); } #endif /* POSITION_DEBUG */ /**************************************************************************** * * Optimized update code * ****************************************************************************/ static inline void GoTo(int const row, int const col) { chtype oldattr = SP->_current_attr; TR(TRACE_MOVE, ("GoTo(%d, %d) from (%d, %d)", row, col, SP->_cursrow, SP->_curscol)); #ifdef POSITION_DEBUG position_check(SP->_cursrow, SP->_curscol, "GoTo"); #endif /* POSITION_DEBUG */ /* * Force restore even if msgr is on when we're in an alternate * character set -- these have a strong tendency to screw up the * CR & LF used for local character motions! */ if ((oldattr & A_ALTCHARSET) || (oldattr && !move_standout_mode)) { TR(TRACE_CHARPUT, ("turning off (%#lx) %s before move", oldattr, _traceattr(oldattr))); vidattr(A_NORMAL); } mvcur(SP->_cursrow, SP->_curscol, row, col); SP->_cursrow = row; SP->_curscol = col; } static inline void PutAttrChar(chtype ch) { if (tilde_glitch && (TextOf(ch) == '~')) ch = ('`' | AttrOf(ch)); TR(TRACE_CHARPUT, ("PutAttrChar(%s) at (%d, %d)", _tracechtype(ch), SP->_cursrow, SP->_curscol)); UpdateAttrs(ch); putc((int)TextOf(ch), SP->_ofp); #ifdef TRACE _nc_outchars++; #endif /* TRACE */ SP->_curscol++; if (char_padding) { TPUTS_TRACE("char_padding"); putp(char_padding); } } static bool check_pending(void) /* check for pending input */ { if (SP->_checkfd >= 0) { #if USE_FUNC_POLL struct pollfd fds[1]; fds[0].fd = SP->_checkfd; fds[0].events = POLLIN; if (poll(fds, 1, 0) > 0) { fflush(SP->_ofp); return TRUE; } #elif HAVE_SELECT fd_set fdset; struct timeval ktimeout; ktimeout.tv_sec = ktimeout.tv_usec = 0; FD_ZERO(&fdset); FD_SET(SP->_checkfd, &fdset); if (select(SP->_checkfd+1, &fdset, NULL, NULL, &ktimeout) > 0) { fflush(SP->_ofp); return TRUE; } #endif } return FALSE; } /* * No one supports recursive inline functions. However, gcc is quieter if we * instantiate the recursive part separately. */ #if CC_HAS_INLINE_FUNCS static void callPutChar(chtype const); #else #define callPutChar(ch) PutChar(ch) #endif static inline void PutChar(chtype const ch) /* insert character, handling automargin stuff */ { if (!(SP->_cursrow == screen_lines-1 && SP->_curscol == screen_columns-1 && auto_right_margin && !eat_newline_glitch)) { PutAttrChar(ch); /* normal case */ } else if (!auto_right_margin /* maybe we can suppress automargin */ || (enter_am_mode && exit_am_mode)) { bool old_am = auto_right_margin; if (old_am) { TPUTS_TRACE("exit_am_mode"); putp(exit_am_mode); } PutAttrChar(ch); if (old_am) { TPUTS_TRACE("enter_am_mode"); putp(enter_am_mode); } } else { GoTo(screen_lines-1,screen_columns-2); callPutChar(ch); GoTo(screen_lines-1,screen_columns-2); if (InsStr(newscr->_line[screen_lines-1].text+screen_columns-2,1)==ERR) return; } if (SP->_curscol >= screen_columns) { if (eat_newline_glitch) { /* * xenl can manifest two different ways. The vt100 * way is that, when you'd expect the cursor to wrap, * it stays hung at the right margin (on top of the * character just emitted) and doesn't wrap until the * *next* graphic char is emitted. The c100 way is * to ignore LF received just after an am wrap. * * An aggressive way to handle this would be to * emit CR/LF after the char and then assume the wrap * is done, you're on the first position of the next * line, and the terminal out of its weird state. * Here it's safe to just tell the code that the * cursor is in hyperspace and let the next mvcur() * call straighten things out. */ SP->_curscol = -1; SP->_cursrow = -1; } else if (auto_right_margin) { SP->_curscol = 0; SP->_cursrow++; } else { SP->_curscol--; } } #ifdef POSITION_DEBUG position_check(SP->_cursrow, SP->_curscol, "PutChar"); #endif /* POSITION_DEBUG */ } /* * Issue a given span of characters from an array. * Must be functionally equivalent to: * for (i = 0; i < num; i++) * PutChar(ntext[i]); * but can leave the cursor positioned at the middle of the interval. * * Returns: 0 - cursor is at the end of interval * 1 - cursor is somewhere in the middle * * This code is optimized using ech and rep. */ static inline int EmitRange(const chtype *ntext, int num) { int i; if (erase_chars || repeat_char) { while (num > 0) { int runcount; chtype ntext0; while (num>1 && ntext[0]!=ntext[1]) { PutChar(ntext[0]); ntext++; num--; } ntext0 = ntext[0]; if (num==1) { PutChar(ntext0); return 0; } runcount = 2; while (runcount < num && ntext[runcount] == ntext0) runcount++; /* * The cost expression in the middle isn't exactly right. * _cup_cost is an upper bound on the cost for moving to the * end of the erased area, but not the cost itself (which we * can't compute without emitting the move). This may result * in erase_chars not getting used in some situations for * which it would be marginally advantageous. */ if (erase_chars && runcount > SP->_ech_cost + SP->_cup_cost && can_clear_with(ntext0)) { UpdateAttrs(ntext0); putp(tparm(erase_chars, runcount)); /* * If this is the last part of the given interval, * don't bother moving cursor, since it can be the * last update on the line. */ if (runcount < num) GoTo(SP->_cursrow, SP->_curscol + runcount); else return 1; /* cursor stays in the middle */ } else if (repeat_char && runcount > SP->_rep_cost) { bool wrap_possible = (SP->_curscol + runcount >= screen_columns); int rep_count = runcount; if (wrap_possible) rep_count--; UpdateAttrs(ntext0); putp(tparm(repeat_char, TextOf(ntext0), rep_count)); SP->_curscol += rep_count; if (wrap_possible) PutChar(ntext0); } else { for (i = 0; i < runcount; i++) PutChar(ntext[i]); } ntext += runcount; num -= runcount; } return 0; } for (i = 0; i < num; i++) PutChar(ntext[i]); return 0; } /* * Output the line in the given range [first .. last] * * If there's a run of identical characters that's long enough to justify * cursor movement, use that also. * * Returns: same as EmitRange */ static int PutRange( const chtype *otext, const chtype *ntext, int row, int first, int last) { int j, run; int cost = min(SP->_cup_ch_cost, SP->_hpa_ch_cost); TR(TRACE_CHARPUT, ("PutRange(%p, %p, %d, %d, %d)", otext, ntext, row, first, last)); if (otext != ntext && (last-first+1) > cost) { for (j = first, run = 0; j <= last; j++) { if (otext[j] == ntext[j]) { run++; } else { if (run > cost) { int before_run = (j - run); EmitRange(ntext+first, before_run-first); GoTo(row, first = j); } run = 0; } } } return EmitRange(ntext + first, last-first+1); } #if CC_HAS_INLINE_FUNCS static void callPutChar(chtype const ch) { PutChar(ch); } #endif #define MARK_NOCHANGE(win,row) \ { \ win->_line[row].firstchar = _NOCHANGE; \ win->_line[row].lastchar = _NOCHANGE; \ win->_line[row].oldindex = row; \ } int doupdate(void) { int i; int nonempty; #if USE_TRACE_TIMES struct tms before, after; #endif /* USE_TRACE_TIMES */ T((T_CALLED("doupdate()"))); #ifdef TRACE if (_nc_tracing & TRACE_UPDATE) { if (curscr->_clear) _tracef("curscr is clear"); else _tracedump("curscr", curscr); _tracedump("newscr", newscr); } #endif /* TRACE */ _nc_signal_handler(FALSE); if (SP->_endwin == TRUE) { T(("coming back from shell mode")); reset_prog_mode(); /* * This is a transparent extension: XSI does not address it, * and applications need not know that ncurses can do it. * * Check if the terminal size has changed while curses was off * (this can happen in an xterm, for example), and resize the * ncurses data structures accordingly. */ _nc_get_screensize(); resizeterm(LINES, COLS); _nc_mvcur_resume(); _nc_mouse_resume(SP); newscr->_clear = TRUE; SP->_endwin = FALSE; } #if USE_TRACE_TIMES /* zero the metering machinery */ _nc_outchars = 0; (void) times(&before); #endif /* USE_TRACE_TIMES */ /* * This is the support for magic-cookie terminals. The * theory: we scan the virtual screen looking for attribute * turnons. Where we find one, check to make sure it's * realizable by seeing if the required number of * un-attributed blanks are present before and after the * attributed range; try to shift the range boundaries over * blanks (not changing the screen display) so this becomes * true. If it is, shift the beginning attribute change * appropriately (the end one, if we've gotten this far, is * guaranteed room for its cookie). If not, nuke the added * attributes out of the span. */ if (magic_cookie_glitch > 0) { int j, k; attr_t rattr = A_NORMAL; for (i = 0; i < screen_lines; i++) for (j = 0; j < screen_columns; j++) { bool failed = FALSE; chtype turnon = AttrOf(newscr->_line[i].text[j]) & ~rattr; /* is an attribute turned on here? */ if (turnon == 0) continue; T(("At (%d, %d): from %s...", i, j, _traceattr(rattr))); T(("...to %s",_traceattr(turnon))); /* * If the attribute change location is a blank with a * "safe" attribute, undo the attribute turnon. This may * ensure there's enough room to set the attribute before * the first non-blank in the run. */ #define SAFE(a) !((a) & ~NONBLANK_ATTR) if (TextOf(newscr->_line[i].text[j])==' ' && SAFE(turnon)) { newscr->_line[i].text[j] &= ~turnon; continue; } /* check that there's enough room at start of span */ for (k = 1; k <= magic_cookie_glitch; k++) if (j-k < 0 || TextOf(newscr->_line[i].text[j-k]) != ' ' || !SAFE(AttrOf(newscr->_line[i].text[j-k]))) failed = TRUE; if (!failed) { bool end_onscreen = FALSE; int m, n = -1; /* find end of span, if it's onscreen */ for (m = i; m < screen_lines; m++) for (n = j; n < screen_columns; n++) if (AttrOf(newscr->_line[m].text[n]) == rattr) { end_onscreen = TRUE; T(("Range attributed with %s ends at (%d, %d)", _traceattr(turnon),m,n)); goto foundit; } T(("Range attributed with %s ends offscreen", _traceattr(turnon))); foundit:; if (end_onscreen) { chtype *lastline = newscr->_line[m].text; /* * If there are safely-attributed blanks at the * end of the range, shorten the range. This will * help ensure that there is enough room at end * of span. */ while (n >= 0 && TextOf(lastline[n]) == ' ' && SAFE(AttrOf(lastline[n]))) lastline[n--] &=~ turnon; /* check that there's enough room at end of span */ for (k = 1; k <= magic_cookie_glitch; k++) if (n + k >= screen_columns || TextOf(lastline[n + k]) != ' ' || !SAFE(AttrOf(lastline[n+k]))) failed = TRUE; } } if (failed) { int p, q; T(("Clearing %s beginning at (%d, %d)", _traceattr(turnon), i, j)); /* turn off new attributes over span */ for (p = i; p < screen_lines; p++) for (q = j; q < screen_columns; q++) if (AttrOf(newscr->_line[p].text[q]) == rattr) goto foundend; else newscr->_line[p].text[q] &=~ turnon; foundend:; } else { T(("Cookie space for %s found before (%d, %d)", _traceattr(turnon), i, j)); /* * back up the start of range so there's room * for cookies before the first nonblank character */ for (k = 1; k <= magic_cookie_glitch; k++) newscr->_line[i].text[j-k] |= turnon; } rattr = AttrOf(newscr->_line[i].text[j]); } #ifdef TRACE /* show altered highlights after magic-cookie check */ if (_nc_tracing & TRACE_UPDATE) { _tracef("After magic-cookie check..."); _tracedump("newscr", newscr); } #endif /* TRACE */ } nonempty = 0; if (curscr->_clear) { /* force refresh ? */ T(("clearing and updating curscr")); ClrUpdate(newscr); /* yes, clear all & update */ curscr->_clear = FALSE; /* reset flag */ } else if (newscr->_clear) { T(("clearing and updating newscr")); ClrUpdate(newscr); newscr->_clear = FALSE; } else { int changedlines; nonempty = min(screen_lines, newscr->_maxy+1); #if 0 /* still 5% slower 960928 */ #if defined(TRACE) || defined(NCURSES_TEST) if (_nc_optimize_enable & OPTIMIZE_HASHMAP) #endif /*TRACE */ _nc_hash_map(); #endif #if defined(TRACE) || defined(NCURSES_TEST) if (_nc_optimize_enable & OPTIMIZE_SCROLL) #endif /*TRACE */ _nc_scroll_optimize(); if (clr_eos) nonempty = ClrBottom(nonempty); T(("Transforming lines, nonempty %d", nonempty)); for (i = changedlines = 0; i < nonempty; i++) { /* * newscr->line[i].firstchar is normally set * by wnoutrefresh. curscr->line[i].firstchar * is normally set by _nc_scroll_window in the * vertical-movement optimization code, */ if (newscr->_line[i].firstchar != _NOCHANGE || curscr->_line[i].firstchar != _NOCHANGE) { TransformLine(i); changedlines++; } /* mark line changed successfully */ if (i <= newscr->_maxy) MARK_NOCHANGE(newscr,i) if (i <= curscr->_maxy) MARK_NOCHANGE(curscr,i) /* * Here is our line-breakout optimization. */ if ((changedlines % CHECK_INTERVAL) == CHECK_INTERVAL-1 && check_pending()) goto cleanup; } } /* put everything back in sync */ for (i = nonempty; i <= newscr->_maxy; i++) MARK_NOCHANGE(newscr,i) for (i = nonempty; i <= curscr->_maxy; i++) MARK_NOCHANGE(curscr,i) curscr->_curx = newscr->_curx; curscr->_cury = newscr->_cury; GoTo(curscr->_cury, curscr->_curx); cleanup: /* * Keep the physical screen in normal mode in case we get other * processes writing to the screen. */ UpdateAttrs(A_NORMAL); fflush(SP->_ofp); curscr->_attrs = newscr->_attrs; /* curscr->_bkgd = newscr->_bkgd; */ #if USE_TRACE_TIMES (void) times(&after); TR(TRACE_TIMES, ("Update cost: %ld chars, %ld clocks system time, %ld clocks user time", _nc_outchars, after.tms_stime-before.tms_stime, after.tms_utime-before.tms_utime)); #endif /* USE_TRACE_TIMES */ _nc_signal_handler(TRUE); returnCode(OK); } /* * ClrBlank(win) * * Returns the attributed character that corresponds to the "cleared" * screen. If the terminal has the back-color-erase feature, this will be * colored according to the wbkgd() call. (Other attributes are * unspecified, hence assumed to be reset in accordance with * 'ClrSetup()'). * * We treat 'curscr' specially because it isn't supposed to be set directly * in the wbkgd() call. Assume 'stdscr' for this case. */ #define BCE_ATTRS (A_NORMAL|A_COLOR) #define BCE_BKGD(win) (((win) == curscr ? stdscr : (win))->_bkgd) static inline chtype ClrBlank (WINDOW *win) { chtype blank = BLANK; if (back_color_erase) blank |= (BCE_BKGD(win) & BCE_ATTRS); return blank; } /* * ClrSetup(win) * * Ensures that if the terminal recognizes back-color-erase, that we * set the video attributes to match the window's background color * before an erase operation. */ static inline chtype ClrSetup (WINDOW *win) { if (back_color_erase) vidattr(BCE_BKGD(win) & BCE_ATTRS); return ClrBlank(win); } /* ** ClrUpdate(scr) ** ** Update by clearing and redrawing the entire screen. ** */ static void ClrUpdate(WINDOW *scr) { int i = 0, j = 0; int lastNonBlank; chtype blank = ClrSetup(scr); T(("ClrUpdate(%p) called", scr)); ClearScreen(); if (scr != curscr) { for (i = 0; i < screen_lines ; i++) for (j = 0; j < screen_columns; j++) curscr->_line[i].text[j] = blank; } T(("updating screen from scratch")); for (i = 0; i < min(screen_lines, scr->_maxy + 1); i++) { lastNonBlank = scr->_maxx; while (lastNonBlank >= 0 && scr->_line[i].text[lastNonBlank] == blank) lastNonBlank--; if (lastNonBlank >= 0) { if (lastNonBlank > screen_columns) lastNonBlank = screen_columns; GoTo(i, 0); PutRange(curscr->_line[i].text, scr->_line[i].text, i, 0, lastNonBlank); } } if (scr != curscr) { for (i = 0; i < screen_lines ; i++) memcpy(curscr->_line[i].text, scr->_line[i].text, screen_columns * sizeof(chtype)); } } /* ** ClrToEOL(blank) ** ** Clear to end of current line, starting at the cursor position */ static void ClrToEOL(chtype blank) { int j; bool needclear = FALSE; for (j = SP->_curscol; j < screen_columns; j++) { chtype *cp = &(curscr->_line[SP->_cursrow].text[j]); if (*cp != blank) { *cp = blank; needclear = TRUE; } } if (needclear) { UpdateAttrs(blank); TPUTS_TRACE("clr_eol"); if (SP->_el_cost > (screen_columns - SP->_curscol)) { int count = (screen_columns - SP->_curscol); while (count-- > 0) PutChar(blank); } else putp(clr_eol); } } /* * ClrBottom(total) * * Test if clearing the end of the screen would satisfy part of the * screen-update. Do this by scanning backwards through the lines in the * screen, checking if each is blank, and one or more are changed. */ static int ClrBottom(int total) { static chtype *tstLine; static size_t lenLine; int row, col; int top = total; int last = min(screen_columns, newscr->_maxx+1); size_t length = sizeof(chtype) * last; chtype blank = newscr->_line[total-1].text[last-1]; /* lower right char */ if(!can_clear_with(blank)) return total; if (tstLine == 0) tstLine = (chtype *)malloc(length); else if (length > lenLine) tstLine = (chtype *)realloc(tstLine, length); if (tstLine != 0) { lenLine = length; for (col = 0; col < last; col++) tstLine[col] = blank; for (row = total-1; row >= 0; row--) { if (memcmp(tstLine, newscr->_line[row].text, length)) break; if (newscr->_line[row].firstchar != _NOCHANGE) top = row; } if (top < total) { GoTo(top,0); UpdateAttrs(blank); TPUTS_TRACE("clr_eos"); putp(clr_eos); while (total-- > top) { for (col = 0; col <= curscr->_maxx; col++) curscr->_line[total].text[col] = blank; } total++; } } #if NO_LEAKS FreeAndNull(tstLine); #endif return total; } /* ** TransformLine(lineno) ** ** Transform the given line in curscr to the one in newscr, using ** Insert/Delete Character if _nc_idcok && has_ic(). ** ** firstChar = position of first different character in line ** oLastChar = position of last different character in old line ** nLastChar = position of last different character in new line ** ** move to firstChar ** overwrite chars up to min(oLastChar, nLastChar) ** if oLastChar < nLastChar ** insert newLine[oLastChar+1..nLastChar] ** else ** delete oLastChar - nLastChar spaces */ static void TransformLine(int const lineno) { int firstChar, oLastChar, nLastChar; chtype *newLine = newscr->_line[lineno].text; chtype *oldLine = curscr->_line[lineno].text; int n; bool attrchanged = FALSE; T(("TransformLine(%d) called", lineno)); if(ceol_standout_glitch && clr_eol) { firstChar = 0; while(firstChar < screen_columns) { if(AttrOf(newLine[firstChar]) != AttrOf(oldLine[firstChar])) attrchanged = TRUE; firstChar++; } } firstChar = 0; if (attrchanged) { /* we may have to disregard the whole line */ GoTo(lineno, firstChar); ClrToEOL(ClrBlank(curscr)); PutRange(oldLine, newLine, lineno, 0, (screen_columns-1)); } else { chtype blank; /* find the first differing character */ while (firstChar < screen_columns && newLine[firstChar] == oldLine[firstChar]) firstChar++; /* if there wasn't one, we're done */ if (firstChar >= screen_columns) return; /* it may be cheap to clear leading whitespace with clr_bol */ if (clr_bol && can_clear_with(blank=newLine[0])) { int oFirstChar, nFirstChar; for (oFirstChar = 0; oFirstChar < screen_columns; oFirstChar++) if (oldLine[oFirstChar] != blank) break; for (nFirstChar = 0; nFirstChar < screen_columns; nFirstChar++) if (newLine[nFirstChar] != blank) break; if (nFirstChar > oFirstChar + SP->_el1_cost) { GoTo(lineno, nFirstChar - 1); UpdateAttrs(blank); TPUTS_TRACE("clr_bol"); putp(clr_bol); while (firstChar < nFirstChar) oldLine[firstChar++] = blank; if (firstChar >= screen_columns) return; } } blank = newLine[screen_columns-1]; if(!can_clear_with(blank)) { /* find the last differing character */ nLastChar = screen_columns - 1; while (nLastChar > firstChar && newLine[nLastChar] == oldLine[nLastChar]) nLastChar--; if (nLastChar >= firstChar) { GoTo(lineno, firstChar); PutRange(oldLine, newLine, lineno, firstChar, nLastChar); memcpy( oldLine + firstChar, newLine + firstChar, (nLastChar - firstChar + 1) * sizeof(chtype)); } return; } /* find last non-blank character on old line */ oLastChar = screen_columns - 1; while (oLastChar > firstChar && oldLine[oLastChar] == blank) oLastChar--; /* find last non-blank character on new line */ nLastChar = screen_columns - 1; while (nLastChar > firstChar && newLine[nLastChar] == blank) nLastChar--; if((nLastChar == firstChar) && (SP->_el_cost < (screen_columns - nLastChar))) { GoTo(lineno, firstChar); ClrToEOL(blank); if(newLine[firstChar] != blank ) PutChar(newLine[firstChar]); } else if( newLine[nLastChar] != oldLine[oLastChar] || !(_nc_idcok && has_ic()) ) { GoTo(lineno, firstChar); if ((oLastChar - nLastChar) > SP->_el_cost) { if(PutRange(oldLine, newLine, lineno, firstChar, nLastChar)) GoTo(lineno, nLastChar+1); ClrToEOL(blank); } else { n = max( nLastChar , oLastChar ); PutRange(oldLine, newLine, lineno, firstChar, n); } } else { int nLastNonblank = nLastChar; int oLastNonblank = oLastChar; /* find the last characters that really differ */ while (newLine[nLastChar] == oldLine[oLastChar]) { if (nLastChar != 0 && oLastChar != 0) { nLastChar--; oLastChar--; } else { break; } } n = min(oLastChar, nLastChar); if (n >= firstChar) { GoTo(lineno, firstChar); PutRange(oldLine, newLine, lineno, firstChar, n); } GoTo(lineno, n+1); if (oLastChar < nLastChar) { int m = max(nLastNonblank, oLastNonblank); if (InsCharCost(nLastChar - oLastChar) > (m - n)) { PutRange(oldLine, newLine, lineno, n+1, m); } else { InsStr(&newLine[n+1], nLastChar - oLastChar); } } else if (oLastChar > nLastChar ) { if (DelCharCost(oLastChar - nLastChar) > SP->_el_cost + nLastNonblank - (n+1)) { if(PutRange(oldLine, newLine, lineno, n+1, nLastNonblank)) GoTo(lineno, nLastNonblank+1); ClrToEOL(blank); } else { /* * The delete-char sequence will * effectively shift in blanks from the * right margin of the screen. Ensure * that they are the right color by * setting the video attributes from * the last character on the row. */ UpdateAttrs(blank); DelChar(oLastChar - nLastChar); } } } } /* update the code's internal representation */ if (screen_columns > firstChar) memcpy( oldLine + firstChar, newLine + firstChar, (screen_columns - firstChar) * sizeof(chtype)); } /* ** ClearScreen() ** ** Clear the physical screen and put cursor at home ** */ static void ClearScreen(void) { T(("ClearScreen() called")); if (clear_screen) { TPUTS_TRACE("clear_screen"); putp(clear_screen); SP->_cursrow = SP->_curscol = 0; #ifdef POSITION_DEBUG position_check(SP->_cursrow, SP->_curscol, "ClearScreen"); #endif /* POSITION_DEBUG */ } else if (clr_eos) { SP->_cursrow = SP->_curscol = -1; GoTo(0,0); TPUTS_TRACE("clr_eos"); putp(clr_eos); } else if (clr_eol) { SP->_cursrow = SP->_curscol = -1; while (SP->_cursrow < screen_lines) { GoTo(SP->_cursrow, 0); TPUTS_TRACE("clr_eol"); putp(clr_eol); } GoTo(0,0); } T(("screen cleared")); } /* ** InsStr(line, count) ** ** Insert the count characters pointed to by line. ** */ static int InsStr(chtype *line, int count) { T(("InsStr(%p,%d) called", line, count)); if (enter_insert_mode && exit_insert_mode) { TPUTS_TRACE("enter_insert_mode"); putp(enter_insert_mode); while (count) { PutAttrChar(*line); line++; count--; } TPUTS_TRACE("exit_insert_mode"); putp(exit_insert_mode); return(OK); } else if (parm_ich) { TPUTS_TRACE("parm_ich"); tputs(tparm(parm_ich, count), count, _nc_outch); while (count) { PutAttrChar(*line); line++; count--; } return(OK); } else { while (count) { TPUTS_TRACE("insert_character"); putp(insert_character); PutAttrChar(*line); if (insert_padding) { TPUTS_TRACE("insert_padding"); putp(insert_padding); } line++; count--; } return(OK); } } /* ** DelChar(count) ** ** Delete count characters at current position ** */ static void DelChar(int count) { T(("DelChar(%d) called, position = (%d,%d)", count, newscr->_cury, newscr->_curx)); if (parm_dch) { TPUTS_TRACE("parm_dch"); tputs(tparm(parm_dch, count), count, _nc_outch); } else { while (count--) { TPUTS_TRACE("delete_character"); putp(delete_character); } } } /* ** _nc_outstr(char *str) ** ** Emit a string without waiting for update. */ void _nc_outstr(const char *str) { FILE *ofp = SP ? SP->_ofp : stdout; (void) fputs(str, ofp); (void) fflush(ofp); #ifdef TRACE _nc_outchars += strlen(str); #endif /* TRACE */ }