1 /****************************************************************************
2 * Copyright (c) 1998-2007,2008 Free Software Foundation, Inc. *
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5 * copy of this software and associated documentation files (the *
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12 * The above copyright notice and this permission notice shall be included *
13 * in all copies or substantial portions of the Software. *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
18 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
21 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
23 * Except as contained in this notice, the name(s) of the above copyright *
24 * holders shall not be used in advertising or otherwise to promote the *
25 * sale, use or other dealings in this Software without prior written *
27 ****************************************************************************/
29 /****************************************************************************
30 * Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
31 * and: Eric S. Raymond <esr@snark.thyrsus.com> *
32 * and: Thomas E. Dickey 1996-on *
33 ****************************************************************************/
38 ** The routines for moving the physical cursor and scrolling:
40 ** void _nc_mvcur_init(void)
42 ** void _nc_mvcur_resume(void)
44 ** int mvcur(int old_y, int old_x, int new_y, int new_x)
46 ** void _nc_mvcur_wrap(void)
48 ** Comparisons with older movement optimizers:
49 ** SVr3 curses mvcur() can't use cursor_to_ll or auto_left_margin.
50 ** 4.4BSD curses can't use cuu/cud/cuf/cub/hpa/vpa/tab/cbt for local
51 ** motions. It doesn't use tactics based on auto_left_margin. Weirdly
52 ** enough, it doesn't use its own hardware-scrolling routine to scroll up
53 ** destination lines for out-of-bounds addresses!
54 ** old ncurses optimizer: less accurate cost computations (in fact,
55 ** it was broken and had to be commented out!).
57 ** Compile with -DMAIN to build an interactive tester/timer for the movement
58 ** optimizer. You can use it to investigate the optimizer's behavior.
59 ** You can also use it for tuning the formulas used to determine whether
60 ** or not full optimization is attempted.
62 ** This code has a nasty tendency to find bugs in terminfo entries, because it
63 ** exercises the non-cup movement capabilities heavily. If you think you've
64 ** found a bug, try deleting subsets of the following capabilities (arranged
65 ** in decreasing order of suspiciousness): it, tab, cbt, hpa, vpa, cuu, cud,
66 ** cuf, cub, cuu1, cud1, cuf1, cub1. It may be that one or more are wrong.
68 ** Note: you should expect this code to look like a resource hog in a profile.
69 ** That's because it does a lot of I/O, through the tputs() calls. The I/O
70 ** cost swamps the computation overhead (and as machines get faster, this
71 ** will become even more true). Comments in the test exerciser at the end
72 ** go into detail about tuning and how you can gauge the optimizer's
76 /****************************************************************************
78 * Constants and macros for optimizer tuning.
80 ****************************************************************************/
83 * The average overhead of a full optimization computation in character
84 * transmission times. If it's too high, the algorithm will be a bit
85 * over-biased toward using cup rather than local motions; if it's too
86 * low, the algorithm may spend more time than is strictly optimal
87 * looking for non-cup motions. Profile the optimizer using the `t'
88 * command of the exerciser (see below), and round to the nearest integer.
90 * Yes, I (esr) thought about computing expected overhead dynamically, say
91 * by derivation from a running average of optimizer times. But the
92 * whole point of this optimization is to *decrease* the frequency of
95 #define COMPUTE_OVERHEAD 1 /* I use a 90MHz Pentium @ 9.6Kbps */
98 * LONG_DIST is the distance we consider to be just as costly to move over as a
99 * cup sequence is to emit. In other words, it's the length of a cup sequence
100 * adjusted for average computation overhead. The magic number is the length
101 * of "\033[yy;xxH", the typical cup sequence these days.
103 #define LONG_DIST (8 - COMPUTE_OVERHEAD)
106 * Tell whether a motion is optimizable by local motions. Needs to be cheap to
107 * compute. In general, all the fast moves go to either the right or left edge
108 * of the screen. So any motion to a location that is (a) further away than
109 * LONG_DIST and (b) further inward from the right or left edge than LONG_DIST,
110 * we'll consider nonlocal.
112 #define NOT_LOCAL(fy, fx, ty, tx) ((tx > LONG_DIST) \
113 && (tx < screen_columns - 1 - LONG_DIST) \
114 && (abs(ty-fy) + abs(tx-fx) > LONG_DIST))
116 /****************************************************************************
118 * External interfaces
120 ****************************************************************************/
123 * For this code to work OK, the following components must live in the
126 * int _char_padding; // cost of character put
127 * int _cr_cost; // cost of (carriage_return)
128 * int _cup_cost; // cost of (cursor_address)
129 * int _home_cost; // cost of (cursor_home)
130 * int _ll_cost; // cost of (cursor_to_ll)
132 * int _ht_cost; // cost of (tab)
133 * int _cbt_cost; // cost of (back_tab)
134 *#endif USE_HARD_TABS
135 * int _cub1_cost; // cost of (cursor_left)
136 * int _cuf1_cost; // cost of (cursor_right)
137 * int _cud1_cost; // cost of (cursor_down)
138 * int _cuu1_cost; // cost of (cursor_up)
139 * int _cub_cost; // cost of (parm_cursor_left)
140 * int _cuf_cost; // cost of (parm_cursor_right)
141 * int _cud_cost; // cost of (parm_cursor_down)
142 * int _cuu_cost; // cost of (parm_cursor_up)
143 * int _hpa_cost; // cost of (column_address)
144 * int _vpa_cost; // cost of (row_address)
145 * int _ech_cost; // cost of (erase_chars)
146 * int _rep_cost; // cost of (repeat_char)
148 * The USE_HARD_TABS switch controls whether it is reliable to use tab/backtabs
149 * for local motions. On many systems, it's not, due to uncertainties about
150 * tab delays and whether or not tabs will be expanded in raw mode. If you
151 * have parm_right_cursor, tab motions don't win you a lot anyhow.
154 #include <curses.priv.h>
158 MODULE_ID("$Id: lib_mvcur.c,v 1.113 2008/08/16 19:30:58 tom Exp $")
160 #define WANT_CHAR(y, x) SP->_newscr->_line[y].text[x] /* desired state */
161 #define BAUDRATE cur_term->_baudrate /* bits per second */
163 #if defined(MAIN) || defined(NCURSES_TEST)
164 #include <sys/time.h>
166 static bool profiling = FALSE;
172 static int normalized_cost(const char *const cap, int affcnt);
174 /****************************************************************************
176 * Initialization/wrapup (including cost pre-computation)
178 ****************************************************************************/
182 trace_cost_of(const char *capname, const char *cap, int affcnt)
184 int result = _nc_msec_cost(cap, affcnt);
185 TR(TRACE_CHARPUT | TRACE_MOVE,
186 ("CostOf %s %d %s", capname, result, _nc_visbuf(cap)));
189 #define CostOf(cap,affcnt) trace_cost_of(#cap,cap,affcnt);
192 trace_normalized_cost(const char *capname, const char *cap, int affcnt)
194 int result = normalized_cost(cap, affcnt);
195 TR(TRACE_CHARPUT | TRACE_MOVE,
196 ("NormalizedCost %s %d %s", capname, result, _nc_visbuf(cap)));
199 #define NormalizedCost(cap,affcnt) trace_normalized_cost(#cap,cap,affcnt);
203 #define CostOf(cap,affcnt) _nc_msec_cost(cap,affcnt);
204 #define NormalizedCost(cap,affcnt) normalized_cost(cap,affcnt);
209 _nc_msec_cost(const char *const cap, int affcnt)
210 /* compute the cost of a given operation */
216 float cum_cost = 0.0;
218 for (cp = cap; *cp; cp++) {
219 /* extract padding, either mandatory or required */
220 if (cp[0] == '$' && cp[1] == '<' && strchr(cp, '>')) {
223 for (cp += 2; *cp != '>'; cp++) {
224 if (isdigit(UChar(*cp)))
225 number = number * 10 + (*cp - '0');
228 else if (*cp == '.' && (*++cp != '>') && isdigit(UChar(*cp)))
229 number += (*cp - '0') / 10.0;
232 #if NCURSES_NO_PADDING
233 if (!GetNoPadding(SP))
235 cum_cost += number * 10;
237 cum_cost += SP->_char_padding;
240 return ((int) cum_cost);
245 normalized_cost(const char *const cap, int affcnt)
246 /* compute the effective character-count for an operation (round up) */
248 int cost = _nc_msec_cost(cap, affcnt);
249 if (cost != INFINITY)
250 cost = (cost + SP->_char_padding - 1) / SP->_char_padding;
255 reset_scroll_region(void)
256 /* Set the scroll-region to a known state (the default) */
258 if (change_scroll_region) {
259 TPUTS_TRACE("change_scroll_region");
260 putp(TPARM_2(change_scroll_region, 0, screen_lines - 1));
265 _nc_mvcur_resume(void)
266 /* what to do at initialization time and after each shellout */
268 /* initialize screen for cursor access */
270 TPUTS_TRACE("enter_ca_mode");
275 * Doing this here rather than in _nc_mvcur_wrap() ensures that
276 * ncurses programs will see a reset scroll region even if a
277 * program that messed with it died ungracefully.
279 * This also undoes the effects of terminal init strings that assume
280 * they know the screen size. This is useful when you're running
281 * a vt100 emulation through xterm.
283 reset_scroll_region();
284 SP->_cursrow = SP->_curscol = -1;
286 /* restore cursor shape */
287 if (SP->_cursor != -1) {
288 int cursor = SP->_cursor;
296 /* initialize the cost structure */
298 if (isatty(fileno(SP->_ofp)))
299 SP->_char_padding = ((BAUDBYTE * 1000 * 10)
300 / (BAUDRATE > 0 ? BAUDRATE : 9600));
302 SP->_char_padding = 1; /* must be nonzero */
303 if (SP->_char_padding <= 0)
304 SP->_char_padding = 1; /* must be nonzero */
305 TR(TRACE_CHARPUT | TRACE_MOVE, ("char_padding %d msecs", SP->_char_padding));
307 /* non-parameterized local-motion strings */
308 SP->_cr_cost = CostOf(carriage_return, 0);
309 SP->_home_cost = CostOf(cursor_home, 0);
310 SP->_ll_cost = CostOf(cursor_to_ll, 0);
312 if (getenv("NCURSES_NO_HARD_TABS") == 0) {
313 SP->_ht_cost = CostOf(tab, 0);
314 SP->_cbt_cost = CostOf(back_tab, 0);
316 SP->_ht_cost = INFINITY;
317 SP->_cbt_cost = INFINITY;
319 #endif /* USE_HARD_TABS */
320 SP->_cub1_cost = CostOf(cursor_left, 0);
321 SP->_cuf1_cost = CostOf(cursor_right, 0);
322 SP->_cud1_cost = CostOf(cursor_down, 0);
323 SP->_cuu1_cost = CostOf(cursor_up, 0);
325 SP->_smir_cost = CostOf(enter_insert_mode, 0);
326 SP->_rmir_cost = CostOf(exit_insert_mode, 0);
328 if (insert_padding) {
329 SP->_ip_cost = CostOf(insert_padding, 0);
333 * Assumption: if the terminal has memory_relative addressing, the
334 * initialization strings or smcup will set single-page mode so we
335 * can treat it like absolute screen addressing. This seems to be true
336 * for all cursor_mem_address terminal types in the terminfo database.
338 SP->_address_cursor = cursor_address ? cursor_address : cursor_mem_address;
341 * Parametrized local-motion strings. This static cost computation
342 * depends on the following assumptions:
344 * (1) They never have * padding. In the entire master terminfo database
345 * as of March 1995, only the obsolete Zenith Z-100 pc violates this.
346 * (Proportional padding is found mainly in insert, delete and scroll
349 * (2) The average case of cup has two two-digit parameters. Strictly,
350 * the average case for a 24 * 80 screen has ((10*10*(1 + 1)) +
351 * (14*10*(1 + 2)) + (10*70*(2 + 1)) + (14*70*4)) / (24*80) = 3.458
352 * digits of parameters. On a 25x80 screen the average is 3.6197.
353 * On larger screens the value gets much closer to 4.
355 * (3) The average case of cub/cuf/hpa/ech/rep has 2 digits of parameters
356 * (strictly, (((10 * 1) + (70 * 2)) / 80) = 1.8750).
358 * (4) The average case of cud/cuu/vpa has 2 digits of parameters
359 * (strictly, (((10 * 1) + (14 * 2)) / 24) = 1.5833).
361 * All these averages depend on the assumption that all parameter values
362 * are equally probable.
364 SP->_cup_cost = CostOf(TPARM_2(SP->_address_cursor, 23, 23), 1);
365 SP->_cub_cost = CostOf(TPARM_1(parm_left_cursor, 23), 1);
366 SP->_cuf_cost = CostOf(TPARM_1(parm_right_cursor, 23), 1);
367 SP->_cud_cost = CostOf(TPARM_1(parm_down_cursor, 23), 1);
368 SP->_cuu_cost = CostOf(TPARM_1(parm_up_cursor, 23), 1);
369 SP->_hpa_cost = CostOf(TPARM_1(column_address, 23), 1);
370 SP->_vpa_cost = CostOf(TPARM_1(row_address, 23), 1);
372 /* non-parameterized screen-update strings */
373 SP->_ed_cost = NormalizedCost(clr_eos, 1);
374 SP->_el_cost = NormalizedCost(clr_eol, 1);
375 SP->_el1_cost = NormalizedCost(clr_bol, 1);
376 SP->_dch1_cost = NormalizedCost(delete_character, 1);
377 SP->_ich1_cost = NormalizedCost(insert_character, 1);
380 * If this is a bce-terminal, we want to bias the choice so we use clr_eol
381 * rather than spaces at the end of a line.
383 if (back_color_erase)
386 /* parameterized screen-update strings */
387 SP->_dch_cost = NormalizedCost(TPARM_1(parm_dch, 23), 1);
388 SP->_ich_cost = NormalizedCost(TPARM_1(parm_ich, 23), 1);
389 SP->_ech_cost = NormalizedCost(TPARM_1(erase_chars, 23), 1);
390 SP->_rep_cost = NormalizedCost(TPARM_2(repeat_char, ' ', 23), 1);
392 SP->_cup_ch_cost = NormalizedCost(TPARM_2(SP->_address_cursor, 23, 23), 1);
393 SP->_hpa_ch_cost = NormalizedCost(TPARM_1(column_address, 23), 1);
394 SP->_cuf_ch_cost = NormalizedCost(TPARM_1(parm_right_cursor, 23), 1);
395 SP->_inline_cost = min(SP->_cup_ch_cost,
396 min(SP->_hpa_ch_cost,
400 * If save_cursor is used within enter_ca_mode, we should not use it for
401 * scrolling optimization, since the corresponding restore_cursor is not
402 * nested on the various terminals (vt100, xterm, etc.) which use this
406 && enter_ca_mode != 0
407 && strstr(enter_ca_mode, save_cursor) != 0) {
408 T(("...suppressed sc/rc capability due to conflict with smcup/rmcup"));
414 * A different, possibly better way to arrange this would be to set
415 * SP->_endwin = TRUE at window initialization time and let this be
416 * called by doupdate's return-from-shellout code.
423 /* wrap up cursor-addressing mode */
425 /* leave cursor at screen bottom */
426 mvcur(-1, -1, screen_lines - 1, 0);
428 /* set cursor to normal mode */
429 if (SP->_cursor != -1) {
430 int cursor = SP->_cursor;
432 SP->_cursor = cursor;
436 TPUTS_TRACE("exit_ca_mode");
440 * Reset terminal's tab counter. There's a long-time bug that
441 * if you exit a "curses" program such as vi or more, tab
442 * forward, and then backspace, the cursor doesn't go to the
443 * right place. The problem is that the kernel counts the
444 * escape sequences that reset things as column positions.
445 * Utter a \r to reset this invisibly.
450 /****************************************************************************
452 * Optimized cursor movement
454 ****************************************************************************/
457 * Perform repeated-append, returning cost
459 static NCURSES_INLINE int
460 repeated_append(string_desc * target, int total, int num, int repeat, const char *src)
462 size_t need = repeat * strlen(src);
464 if (need < target->s_size) {
465 while (repeat-- > 0) {
466 if (_nc_safe_strcat(target, src)) {
480 #define NEXTTAB(fr) (fr + init_tabs - (fr % init_tabs))
483 * Assume back_tab (CBT) does not wrap backwards at the left margin, return
484 * a negative value at that point to simplify the loop.
486 #define LASTTAB(fr) ((fr > 0) ? ((fr - 1) / init_tabs) * init_tabs : -1)
489 relative_move(string_desc * target, int from_y, int from_x, int to_y, int
491 /* move via local motions (cuu/cuu1/cud/cud1/cub1/cub/cuf1/cuf/vpa/hpa) */
494 int n, vcost = 0, hcost = 0;
496 (void) _nc_str_copy(&save, target);
498 if (to_y != from_y) {
502 && _nc_safe_strcat(target, TPARM_1(row_address, to_y))) {
503 vcost = SP->_vpa_cost;
510 && SP->_cud_cost < vcost
511 && _nc_safe_strcat(_nc_str_copy(target, &save),
512 TPARM_1(parm_down_cursor, n))) {
513 vcost = SP->_cud_cost;
517 && (*cursor_down != '\n' || SP->_nl)
518 && (n * SP->_cud1_cost < vcost)) {
519 vcost = repeated_append(_nc_str_copy(target, &save), 0,
520 SP->_cud1_cost, n, cursor_down);
522 } else { /* (to_y < from_y) */
526 && SP->_cuu_cost < vcost
527 && _nc_safe_strcat(_nc_str_copy(target, &save),
528 TPARM_1(parm_up_cursor, n))) {
529 vcost = SP->_cuu_cost;
532 if (cursor_up && (n * SP->_cuu1_cost < vcost)) {
533 vcost = repeated_append(_nc_str_copy(target, &save), 0,
534 SP->_cuu1_cost, n, cursor_up);
538 if (vcost == INFINITY)
544 if (to_x != from_x) {
551 && _nc_safe_strcat(_nc_str_copy(target, &save),
552 TPARM_1(column_address, to_x))) {
553 hcost = SP->_hpa_cost;
559 if (parm_right_cursor
560 && SP->_cuf_cost < hcost
561 && _nc_safe_strcat(_nc_str_copy(target, &save),
562 TPARM_1(parm_right_cursor, n))) {
563 hcost = SP->_cuf_cost;
569 (void) _nc_str_init(&check, str, sizeof(str));
572 /* use hard tabs, if we have them, to do as much as possible */
573 if (init_tabs > 0 && tab) {
576 for (fr = from_x; (nxt = NEXTTAB(fr)) <= to_x; fr = nxt) {
577 lhcost = repeated_append(&check, lhcost,
578 SP->_ht_cost, 1, tab);
579 if (lhcost == INFINITY)
586 #endif /* USE_HARD_TABS */
588 if (n <= 0 || n >= (int) check.s_size)
592 * If we're allowing BSD-style padding in tputs, don't generate
593 * a string with a leading digit. Otherwise, that will be
594 * interpreted as a padding value rather than sent to the
599 && n < (int) check.s_size
602 int wanted = CharOf(WANT_CHAR(to_y, from_x));
603 if (is8bits(wanted) && isdigit(wanted))
608 * If we have no attribute changes, overwrite is cheaper.
609 * Note: must suppress this by passing in ovw = FALSE whenever
610 * WANT_CHAR would return invalid data. In particular, this
611 * is true between the time a hardware scroll has been done
612 * and the time the structure WANT_CHAR would access has been
618 for (i = 0; i < n; i++) {
619 NCURSES_CH_T ch = WANT_CHAR(to_y, from_x + i);
620 if (!SameAttrOf(ch, SCREEN_ATTRS(SP))
621 #if USE_WIDEC_SUPPORT
633 for (i = 0; i < n; i++)
634 *check.s_tail++ = (char) CharOf(WANT_CHAR(to_y,
636 *check.s_tail = '\0';
638 lhcost += n * SP->_char_padding;
640 lhcost = repeated_append(&check, lhcost, SP->_cuf1_cost,
645 && _nc_safe_strcat(_nc_str_copy(target, &save), str)) {
649 } else { /* (to_x < from_x) */
653 && SP->_cub_cost < hcost
654 && _nc_safe_strcat(_nc_str_copy(target, &save),
655 TPARM_1(parm_left_cursor, n))) {
656 hcost = SP->_cub_cost;
662 (void) _nc_str_init(&check, str, sizeof(str));
665 if (init_tabs > 0 && back_tab) {
668 for (fr = from_x; (nxt = LASTTAB(fr)) >= to_x; fr = nxt) {
669 lhcost = repeated_append(&check, lhcost,
670 SP->_cbt_cost, 1, back_tab);
671 if (lhcost == INFINITY)
677 #endif /* USE_HARD_TABS */
679 lhcost = repeated_append(&check, lhcost, SP->_cub1_cost, n, cursor_left);
682 && _nc_safe_strcat(_nc_str_copy(target, &save), str)) {
688 if (hcost == INFINITY)
692 return (vcost + hcost);
694 #endif /* !NO_OPTIMIZE */
697 * With the machinery set up above, it's conceivable that
698 * onscreen_mvcur could be modified into a recursive function that does
699 * an alpha-beta search of motion space, as though it were a chess
700 * move tree, with the weight function being boolean and the search
701 * depth equated to length of string. However, this would jack up the
702 * computation cost a lot, especially on terminals without a cup
703 * capability constraining the search tree depth. So we settle for
704 * the simpler method below.
707 static NCURSES_INLINE int
708 onscreen_mvcur(int yold, int xold, int ynew, int xnew, bool ovw)
709 /* onscreen move from (yold, xold) to (ynew, xnew) */
712 char buffer[OPT_SIZE];
713 int tactic = 0, newcost, usecost = INFINITY;
716 #if defined(MAIN) || defined(NCURSES_TEST)
717 struct timeval before, after;
719 gettimeofday(&before, NULL);
722 #define NullResult _nc_str_null(&result, sizeof(buffer))
723 #define InitResult _nc_str_init(&result, buffer, sizeof(buffer))
725 /* tactic #0: use direct cursor addressing */
726 if (_nc_safe_strcpy(InitResult, TPARM_2(SP->_address_cursor, ynew, xnew))) {
728 usecost = SP->_cup_cost;
730 #if defined(TRACE) || defined(NCURSES_TEST)
731 if (!(_nc_optimize_enable & OPTIMIZE_MVCUR))
736 * We may be able to tell in advance that the full optimization
737 * will probably not be worth its overhead. Also, don't try to
738 * use local movement if the current attribute is anything but
739 * A_NORMAL...there are just too many ways this can screw up
740 * (like, say, local-movement \n getting mapped to some obscure
741 * character because A_ALTCHARSET is on).
743 if (yold == -1 || xold == -1 || NOT_LOCAL(yold, xold, ynew, xnew)) {
744 #if defined(MAIN) || defined(NCURSES_TEST)
746 (void) fputs("nonlocal\n", stderr);
747 goto nonlocal; /* always run the optimizer if profiling */
755 /* tactic #1: use local movement */
756 if (yold != -1 && xold != -1
757 && ((newcost = relative_move(NullResult, yold, xold, ynew, xnew,
759 && newcost < usecost) {
764 /* tactic #2: use carriage-return + local movement */
765 if (yold != -1 && carriage_return
766 && ((newcost = relative_move(NullResult, yold, 0, ynew, xnew, ovw))
768 && SP->_cr_cost + newcost < usecost) {
770 usecost = SP->_cr_cost + newcost;
773 /* tactic #3: use home-cursor + local movement */
775 && ((newcost = relative_move(NullResult, 0, 0, ynew, xnew, ovw)) != INFINITY)
776 && SP->_home_cost + newcost < usecost) {
778 usecost = SP->_home_cost + newcost;
781 /* tactic #4: use home-down + local movement */
783 && ((newcost = relative_move(NullResult, screen_lines - 1, 0, ynew,
784 xnew, ovw)) != INFINITY)
785 && SP->_ll_cost + newcost < usecost) {
787 usecost = SP->_ll_cost + newcost;
791 * tactic #5: use left margin for wrap to right-hand side,
792 * unless strange wrap behavior indicated by xenl might hose us.
794 t5_cr_cost = (xold > 0 ? SP->_cr_cost : 0);
795 if (auto_left_margin && !eat_newline_glitch
796 && yold > 0 && cursor_left
797 && ((newcost = relative_move(NullResult, yold - 1, screen_columns -
798 1, ynew, xnew, ovw)) != INFINITY)
799 && t5_cr_cost + SP->_cub1_cost + newcost < usecost) {
801 usecost = t5_cr_cost + SP->_cub1_cost + newcost;
805 * These cases are ordered by estimated relative frequency.
811 (void) relative_move(&result, yold, xold, ynew, xnew, ovw);
814 (void) _nc_safe_strcpy(&result, carriage_return);
815 (void) relative_move(&result, yold, 0, ynew, xnew, ovw);
818 (void) _nc_safe_strcpy(&result, cursor_home);
819 (void) relative_move(&result, 0, 0, ynew, xnew, ovw);
822 (void) _nc_safe_strcpy(&result, cursor_to_ll);
823 (void) relative_move(&result, screen_lines - 1, 0, ynew, xnew, ovw);
827 (void) _nc_safe_strcat(&result, carriage_return);
828 (void) _nc_safe_strcat(&result, cursor_left);
829 (void) relative_move(&result, yold - 1, screen_columns - 1, ynew,
833 #endif /* !NO_OPTIMIZE */
836 #if defined(MAIN) || defined(NCURSES_TEST)
837 gettimeofday(&after, NULL);
838 diff = after.tv_usec - before.tv_usec
839 + (after.tv_sec - before.tv_sec) * 1000000;
841 (void) fprintf(stderr,
842 "onscreen: %d microsec, %f 28.8Kbps char-equivalents\n",
843 (int) diff, diff / 288);
846 if (usecost != INFINITY) {
847 TPUTS_TRACE("mvcur");
848 tputs(buffer, 1, _nc_outch);
857 mvcur(int yold, int xold, int ynew, int xnew)
858 /* optimized cursor move from (yold, xold) to (ynew, xnew) */
860 NCURSES_CH_T oldattr;
863 TR(TRACE_CALLS | TRACE_MOVE, (T_CALLED("mvcur(%d,%d,%d,%d)"),
864 yold, xold, ynew, xnew));
868 } else if (yold == ynew && xold == xnew) {
873 * Most work here is rounding for terminal boundaries getting the
874 * column position implied by wraparound or the lack thereof and
875 * rolling up the screen to get ynew on the screen.
877 if (xnew >= screen_columns) {
878 ynew += xnew / screen_columns;
879 xnew %= screen_columns;
883 * Force restore even if msgr is on when we're in an alternate
884 * character set -- these have a strong tendency to screw up the CR &
885 * LF used for local character motions!
887 oldattr = SCREEN_ATTRS(SP);
888 if ((AttrOf(oldattr) & A_ALTCHARSET)
889 || (AttrOf(oldattr) && !move_standout_mode)) {
890 TR(TRACE_CHARPUT, ("turning off (%#lx) %s before move",
891 (unsigned long) AttrOf(oldattr),
892 _traceattr(AttrOf(oldattr))));
893 (void) VIDATTR(A_NORMAL, 0);
896 if (xold >= screen_columns) {
900 l = (xold + 1) / screen_columns;
902 if (yold >= screen_lines)
903 l -= (yold - screen_lines - 1);
906 if (carriage_return) {
907 TPUTS_TRACE("carriage_return");
908 putp(carriage_return);
915 TPUTS_TRACE("newline");
924 * If caller set nonl(), we cannot really use newlines to
925 * position to the next row.
932 if (yold > screen_lines - 1)
933 yold = screen_lines - 1;
934 if (ynew > screen_lines - 1)
935 ynew = screen_lines - 1;
937 /* destination location is on screen now */
938 code = onscreen_mvcur(yold, xold, ynew, xnew, TRUE);
941 * Restore attributes if we disabled them before moving.
943 if (!SameAttrOf(oldattr, SCREEN_ATTRS(SP))) {
944 TR(TRACE_CHARPUT, ("turning on (%#lx) %s after move",
945 (unsigned long) AttrOf(oldattr),
946 _traceattr(AttrOf(oldattr))));
947 (void) VIDATTR(AttrOf(oldattr), GetPair(oldattr));
953 #if defined(TRACE) || defined(NCURSES_TEST)
954 NCURSES_EXPORT_VAR(int) _nc_optimize_enable = OPTIMIZE_ALL;
957 #if defined(MAIN) || defined(NCURSES_TEST)
958 /****************************************************************************
960 * Movement optimizer test code
962 ****************************************************************************/
965 #include <dump_entry.h>
968 NCURSES_EXPORT_VAR(const char *) _nc_progname = "mvcur";
970 static unsigned long xmits;
972 /* these override lib_tputs.c */
974 tputs(const char *string, int affcnt GCC_UNUSED, int (*outc) (int) GCC_UNUSED)
975 /* stub tputs() that dumps sequences in a visible form */
978 xmits += strlen(string);
980 (void) fputs(_nc_visbuf(string), stdout);
985 putp(const char *string)
987 return (tputs(string, 1, _nc_outch));
998 delay_output(int ms GCC_UNUSED)
1003 static char tname[PATH_MAX];
1008 (void) setupterm(tname, STDOUT_FILENO, NULL);
1016 i = (RAND_MAX / n) * n;
1017 while ((j = rand()) >= i)
1023 main(int argc GCC_UNUSED, char *argv[]GCC_UNUSED)
1025 strcpy(tname, getenv("TERM"));
1027 _nc_setupscreen(lines, columns, stdout, FALSE, 0);
1033 (void) puts("The mvcur tester. Type ? for help");
1035 fputs("smcup:", stdout);
1039 int fy, fx, ty, tx, n, i;
1040 char buf[BUFSIZ], capname[BUFSIZ];
1042 (void) fputs("> ", stdout);
1043 (void) fgets(buf, sizeof(buf), stdin);
1045 if (buf[0] == '?') {
1046 (void) puts("? -- display this help message");
1048 puts("fy fx ty tx -- (4 numbers) display (fy,fx)->(ty,tx) move");
1049 (void) puts("s[croll] n t b m -- display scrolling sequence");
1051 printf("r[eload] -- reload terminal info for %s\n",
1054 puts("l[oad] <term> -- load terminal info for type <term>");
1055 (void) puts("d[elete] <cap> -- delete named capability");
1056 (void) puts("i[nspect] -- display terminal capabilities");
1058 puts("c[ost] -- dump cursor-optimization cost table");
1059 (void) puts("o[optimize] -- toggle movement optimization");
1061 puts("t[orture] <num> -- torture-test with <num> random moves");
1062 (void) puts("q[uit] -- quit the program");
1063 } else if (sscanf(buf, "%d %d %d %d", &fy, &fx, &ty, &tx) == 4) {
1064 struct timeval before, after;
1068 gettimeofday(&before, NULL);
1069 mvcur(fy, fx, ty, tx);
1070 gettimeofday(&after, NULL);
1072 printf("\" (%ld msec)\n",
1073 (long) (after.tv_usec - before.tv_usec
1074 + (after.tv_sec - before.tv_sec)
1076 } else if (sscanf(buf, "s %d %d %d %d", &fy, &fx, &ty, &tx) == 4) {
1077 struct timeval before, after;
1081 gettimeofday(&before, NULL);
1082 _nc_scrolln(fy, fx, ty, tx);
1083 gettimeofday(&after, NULL);
1085 printf("\" (%ld msec)\n",
1086 (long) (after.tv_usec - before.tv_usec + (after.tv_sec -
1089 } else if (buf[0] == 'r') {
1090 (void) strcpy(tname, termname());
1092 } else if (sscanf(buf, "l %s", tname) == 1) {
1094 } else if (sscanf(buf, "d %s", capname) == 1) {
1095 struct name_table_entry const *np = _nc_find_entry(capname,
1096 _nc_get_hash_table(FALSE));
1099 (void) printf("No such capability as \"%s\"\n", capname);
1101 switch (np->nte_type) {
1103 cur_term->type.Booleans[np->nte_index] = FALSE;
1105 printf("Boolean capability `%s' (%d) turned off.\n",
1106 np->nte_name, np->nte_index);
1110 cur_term->type.Numbers[np->nte_index] = ABSENT_NUMERIC;
1111 (void) printf("Number capability `%s' (%d) set to -1.\n",
1112 np->nte_name, np->nte_index);
1116 cur_term->type.Strings[np->nte_index] = ABSENT_STRING;
1117 (void) printf("String capability `%s' (%d) deleted.\n",
1118 np->nte_name, np->nte_index);
1122 } else if (buf[0] == 'i') {
1123 dump_init((char *) NULL, F_TERMINFO, S_TERMINFO, 70, 0, FALSE);
1124 dump_entry(&cur_term->type, FALSE, TRUE, 0, 0);
1126 } else if (buf[0] == 'o') {
1127 if (_nc_optimize_enable & OPTIMIZE_MVCUR) {
1128 _nc_optimize_enable &= ~OPTIMIZE_MVCUR;
1129 (void) puts("Optimization is now off.");
1131 _nc_optimize_enable |= OPTIMIZE_MVCUR;
1132 (void) puts("Optimization is now on.");
1136 * You can use the `t' test to profile and tune the movement
1137 * optimizer. Use iteration values in three digits or more.
1138 * At above 5000 iterations the profile timing averages are stable
1139 * to within a millisecond or three.
1141 * The `overhead' field of the report will help you pick a
1142 * COMPUTE_OVERHEAD figure appropriate for your processor and
1143 * expected line speed. The `total estimated time' is
1144 * computation time plus a character-transmission time
1145 * estimate computed from the number of transmits and the baud
1148 * Use this together with the `o' command to get a read on the
1149 * optimizer's effectiveness. Compare the total estimated times
1150 * for `t' runs of the same length in both optimized and un-optimized
1151 * modes. As long as the optimized times are less, the optimizer
1154 else if (sscanf(buf, "t %d", &n) == 1) {
1155 float cumtime = 0.0, perchar;
1157 {2400, 9600, 14400, 19200, 28800, 38400, 0};
1159 srand((unsigned) (getpid() + time((time_t *) 0)));
1162 for (i = 0; i < n; i++) {
1164 * This does a move test between two random locations,
1165 * Random moves probably short-change the optimizer,
1166 * which will work better on the short moves probably
1167 * typical of doupdate()'s usage pattern. Still,
1168 * until we have better data...
1170 #ifdef FIND_COREDUMP
1171 int from_y = roll(lines);
1172 int to_y = roll(lines);
1173 int from_x = roll(columns);
1174 int to_x = roll(columns);
1176 printf("(%d,%d) -> (%d,%d)\n", from_y, from_x, to_y, to_x);
1177 mvcur(from_y, from_x, to_y, to_x);
1179 mvcur(roll(lines), roll(columns), roll(lines), roll(columns));
1180 #endif /* FIND_COREDUMP */
1187 * Average milliseconds per character optimization time.
1188 * This is the key figure to watch when tuning the optimizer.
1190 perchar = cumtime / n;
1192 (void) printf("%d moves (%ld chars) in %d msec, %f msec each:\n",
1193 n, xmits, (int) cumtime, perchar);
1195 for (i = 0; speeds[i]; i++) {
1197 * Total estimated time for the moves, computation and
1198 * transmission both. Transmission time is an estimate
1199 * assuming 9 bits/char, 8 bits + 1 stop bit.
1201 float totalest = cumtime + xmits * 9 * 1e6 / speeds[i];
1204 * Per-character optimization overhead in character transmits
1205 * at the current speed. Round this to the nearest integer
1206 * to figure COMPUTE_OVERHEAD for the speed.
1208 float overhead = speeds[i] * perchar / 1e6;
1211 printf("%6d bps: %3.2f char-xmits overhead; total estimated time %15.2f\n",
1212 speeds[i], overhead, totalest);
1214 } else if (buf[0] == 'c') {
1215 (void) printf("char padding: %d\n", SP->_char_padding);
1216 (void) printf("cr cost: %d\n", SP->_cr_cost);
1217 (void) printf("cup cost: %d\n", SP->_cup_cost);
1218 (void) printf("home cost: %d\n", SP->_home_cost);
1219 (void) printf("ll cost: %d\n", SP->_ll_cost);
1221 (void) printf("ht cost: %d\n", SP->_ht_cost);
1222 (void) printf("cbt cost: %d\n", SP->_cbt_cost);
1223 #endif /* USE_HARD_TABS */
1224 (void) printf("cub1 cost: %d\n", SP->_cub1_cost);
1225 (void) printf("cuf1 cost: %d\n", SP->_cuf1_cost);
1226 (void) printf("cud1 cost: %d\n", SP->_cud1_cost);
1227 (void) printf("cuu1 cost: %d\n", SP->_cuu1_cost);
1228 (void) printf("cub cost: %d\n", SP->_cub_cost);
1229 (void) printf("cuf cost: %d\n", SP->_cuf_cost);
1230 (void) printf("cud cost: %d\n", SP->_cud_cost);
1231 (void) printf("cuu cost: %d\n", SP->_cuu_cost);
1232 (void) printf("hpa cost: %d\n", SP->_hpa_cost);
1233 (void) printf("vpa cost: %d\n", SP->_vpa_cost);
1234 } else if (buf[0] == 'x' || buf[0] == 'q')
1237 (void) puts("Invalid command.");
1240 (void) fputs("rmcup:", stdout);
1249 /* lib_mvcur.c ends here */