1 /****************************************************************************
2 * Copyright 2018-2020,2021 Thomas E. Dickey *
3 * Copyright 1998-2016,2017 Free Software Foundation, Inc. *
5 * Permission is hereby granted, free of charge, to any person obtaining a *
6 * copy of this software and associated documentation files (the *
7 * "Software"), to deal in the Software without restriction, including *
8 * without limitation the rights to use, copy, modify, merge, publish, *
9 * distribute, distribute with modifications, sublicense, and/or sell *
10 * copies of the Software, and to permit persons to whom the Software is *
11 * furnished to do so, subject to the following conditions: *
13 * The above copyright notice and this permission notice shall be included *
14 * in all copies or substantial portions of the Software. *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
19 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
21 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
22 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
24 * Except as contained in this notice, the name(s) of the above copyright *
25 * holders shall not be used in advertising or otherwise to promote the *
26 * sale, use or other dealings in this Software without prior written *
28 ****************************************************************************/
30 /****************************************************************************
31 * Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
32 * and: Eric S. Raymond <esr@snark.thyrsus.com> *
33 * and: Thomas E. Dickey 1996-on *
34 * and: Juergen Pfeifer 2009 *
35 ****************************************************************************/
40 ** The routines for moving the physical cursor and scrolling:
42 ** void _nc_mvcur_init(void)
44 ** void _nc_mvcur_resume(void)
46 ** int mvcur(int old_y, int old_x, int new_y, int new_x)
48 ** void _nc_mvcur_wrap(void)
50 ** Comparisons with older movement optimizers:
51 ** SVr3 curses mvcur() can't use cursor_to_ll or auto_left_margin.
52 ** 4.4BSD curses can't use cuu/cud/cuf/cub/hpa/vpa/tab/cbt for local
53 ** motions. It doesn't use tactics based on auto_left_margin. Weirdly
54 ** enough, it doesn't use its own hardware-scrolling routine to scroll up
55 ** destination lines for out-of-bounds addresses!
56 ** old ncurses optimizer: less accurate cost computations (in fact,
57 ** it was broken and had to be commented out!).
59 ** Compile with -DMAIN to build an interactive tester/timer for the movement
60 ** optimizer. You can use it to investigate the optimizer's behavior.
61 ** You can also use it for tuning the formulas used to determine whether
62 ** or not full optimization is attempted.
64 ** This code has a nasty tendency to find bugs in terminfo entries, because it
65 ** exercises the non-cup movement capabilities heavily. If you think you've
66 ** found a bug, try deleting subsets of the following capabilities (arranged
67 ** in decreasing order of suspiciousness): it, tab, cbt, hpa, vpa, cuu, cud,
68 ** cuf, cub, cuu1, cud1, cuf1, cub1. It may be that one or more are wrong.
70 ** Note: you should expect this code to look like a resource hog in a profile.
71 ** That's because it does a lot of I/O, through the tputs() calls. The I/O
72 ** cost swamps the computation overhead (and as machines get faster, this
73 ** will become even more true). Comments in the test exerciser at the end
74 ** go into detail about tuning and how you can gauge the optimizer's
78 /****************************************************************************
80 * Constants and macros for optimizer tuning.
82 ****************************************************************************/
85 * The average overhead of a full optimization computation in character
86 * transmission times. If it's too high, the algorithm will be a bit
87 * over-biased toward using cup rather than local motions; if it's too
88 * low, the algorithm may spend more time than is strictly optimal
89 * looking for non-cup motions. Profile the optimizer using the `t'
90 * command of the exerciser (see below), and round to the nearest integer.
92 * Yes, I (esr) thought about computing expected overhead dynamically, say
93 * by derivation from a running average of optimizer times. But the
94 * whole point of this optimization is to *decrease* the frequency of
97 #define COMPUTE_OVERHEAD 1 /* I use a 90MHz Pentium @ 9.6Kbps */
100 * LONG_DIST is the distance we consider to be just as costly to move over as a
101 * cup sequence is to emit. In other words, it's the length of a cup sequence
102 * adjusted for average computation overhead. The magic number is the length
103 * of "\033[yy;xxH", the typical cup sequence these days.
105 #define LONG_DIST (8 - COMPUTE_OVERHEAD)
108 * Tell whether a motion is optimizable by local motions. Needs to be cheap to
109 * compute. In general, all the fast moves go to either the right or left edge
110 * of the screen. So any motion to a location that is (a) further away than
111 * LONG_DIST and (b) further inward from the right or left edge than LONG_DIST,
112 * we'll consider nonlocal.
114 #define NOT_LOCAL(sp, fy, fx, ty, tx) ((tx > LONG_DIST) \
115 && (tx < screen_columns(sp) - 1 - LONG_DIST) \
116 && (abs(ty-fy) + abs(tx-fx) > LONG_DIST))
118 /****************************************************************************
120 * External interfaces
122 ****************************************************************************/
125 * For this code to work OK, the following components must live in the
128 * int _char_padding; // cost of character put
129 * int _cr_cost; // cost of (carriage_return)
130 * int _cup_cost; // cost of (cursor_address)
131 * int _home_cost; // cost of (cursor_home)
132 * int _ll_cost; // cost of (cursor_to_ll)
134 * int _ht_cost; // cost of (tab)
135 * int _cbt_cost; // cost of (back_tab)
136 *#endif USE_HARD_TABS
137 * int _cub1_cost; // cost of (cursor_left)
138 * int _cuf1_cost; // cost of (cursor_right)
139 * int _cud1_cost; // cost of (cursor_down)
140 * int _cuu1_cost; // cost of (cursor_up)
141 * int _cub_cost; // cost of (parm_cursor_left)
142 * int _cuf_cost; // cost of (parm_cursor_right)
143 * int _cud_cost; // cost of (parm_cursor_down)
144 * int _cuu_cost; // cost of (parm_cursor_up)
145 * int _hpa_cost; // cost of (column_address)
146 * int _vpa_cost; // cost of (row_address)
147 * int _ech_cost; // cost of (erase_chars)
148 * int _rep_cost; // cost of (repeat_char)
150 * The USE_HARD_TABS switch controls whether it is reliable to use tab/backtabs
151 * for local motions. On many systems, it's not, due to uncertainties about
152 * tab delays and whether or not tabs will be expanded in raw mode. If you
153 * have parm_right_cursor, tab motions don't win you a lot anyhow.
156 #include <curses.priv.h>
160 #define CUR SP_TERMTYPE
163 MODULE_ID("$Id: lib_mvcur.c,v 1.155 2021/02/06 13:53:41 tom Exp $")
165 #define WANT_CHAR(sp, y, x) NewScreen(sp)->_line[y].text[x] /* desired state */
168 #define BAUDRATE(sp) sp->_term->_baudrate /* bits per second */
170 #define BAUDRATE(sp) cur_term->_baudrate /* bits per second */
173 #if defined(MAIN) || defined(NCURSES_TEST)
174 #include <sys/time.h>
176 static bool profiling = FALSE;
180 #undef NCURSES_OUTC_FUNC
181 #define NCURSES_OUTC_FUNC myOutCh
185 static int normalized_cost(NCURSES_SP_DCLx const char *const cap, int affcnt);
187 /****************************************************************************
189 * Initialization/wrapup (including cost pre-computation)
191 ****************************************************************************/
195 trace_cost_of(NCURSES_SP_DCLx const char *capname, const char *cap, int affcnt)
197 int result = NCURSES_SP_NAME(_nc_msec_cost) (NCURSES_SP_ARGx cap, affcnt);
198 TR(TRACE_CHARPUT | TRACE_MOVE,
199 ("CostOf %s %d %s", capname, result, _nc_visbuf(cap)));
202 #define CostOf(cap,affcnt) trace_cost_of(NCURSES_SP_ARGx #cap, cap, affcnt)
205 trace_normalized_cost(NCURSES_SP_DCLx const char *capname, const char *cap, int affcnt)
207 int result = normalized_cost(NCURSES_SP_ARGx cap, affcnt);
208 TR(TRACE_CHARPUT | TRACE_MOVE,
209 ("NormalizedCost %s %d %s", capname, result, _nc_visbuf(cap)));
212 #define NormalizedCost(cap,affcnt) trace_normalized_cost(NCURSES_SP_ARGx #cap, cap, affcnt)
216 #define CostOf(cap,affcnt) NCURSES_SP_NAME(_nc_msec_cost)(NCURSES_SP_ARGx cap, affcnt)
217 #define NormalizedCost(cap,affcnt) normalized_cost(NCURSES_SP_ARGx cap, affcnt)
222 NCURSES_SP_NAME(_nc_msec_cost) (NCURSES_SP_DCLx const char *const cap, int affcnt)
223 /* compute the cost of a given operation */
229 float cum_cost = 0.0;
231 for (cp = cap; *cp; cp++) {
232 /* extract padding, either mandatory or required */
233 if (cp[0] == '$' && cp[1] == '<' && strchr(cp, '>')) {
236 for (cp += 2; *cp != '>'; cp++) {
237 if (isdigit(UChar(*cp)))
238 number = number * 10 + (float) (*cp - '0');
240 number *= (float) affcnt;
241 else if (*cp == '.' && (*++cp != '>') && isdigit(UChar(*cp)))
242 number += (float) ((*cp - '0') / 10.0);
245 #if NCURSES_NO_PADDING
246 if (!GetNoPadding(SP_PARM))
248 cum_cost += number * 10;
249 } else if (SP_PARM) {
250 cum_cost += (float) SP_PARM->_char_padding;
254 return ((int) cum_cost);
260 _nc_msec_cost(const char *const cap, int affcnt)
262 return NCURSES_SP_NAME(_nc_msec_cost) (CURRENT_SCREEN, cap, affcnt);
267 normalized_cost(NCURSES_SP_DCLx const char *const cap, int affcnt)
268 /* compute the effective character-count for an operation (round up) */
270 int cost = NCURSES_SP_NAME(_nc_msec_cost) (NCURSES_SP_ARGx cap, affcnt);
271 if (cost != INFINITY)
272 cost = (cost + SP_PARM->_char_padding - 1) / SP_PARM->_char_padding;
277 reset_scroll_region(NCURSES_SP_DCL0)
278 /* Set the scroll-region to a known state (the default) */
280 if (change_scroll_region) {
281 NCURSES_PUTP2("change_scroll_region",
282 TIPARM_2(change_scroll_region,
283 0, screen_lines(SP_PARM) - 1));
288 NCURSES_SP_NAME(_nc_mvcur_resume) (NCURSES_SP_DCL0)
289 /* what to do at initialization time and after each shellout */
291 if (!SP_PARM || !IsTermInfo(SP_PARM))
294 /* initialize screen for cursor access */
296 NCURSES_PUTP2("enter_ca_mode", enter_ca_mode);
300 * Doing this here rather than in _nc_mvcur_wrap() ensures that
301 * ncurses programs will see a reset scroll region even if a
302 * program that messed with it died ungracefully.
304 * This also undoes the effects of terminal init strings that assume
305 * they know the screen size. This is useful when you're running
306 * a vt100 emulation through xterm.
308 reset_scroll_region(NCURSES_SP_ARG);
309 SP_PARM->_cursrow = SP_PARM->_curscol = -1;
311 /* restore cursor shape */
312 if (SP_PARM->_cursor != -1) {
313 int cursor = SP_PARM->_cursor;
314 SP_PARM->_cursor = -1;
315 NCURSES_SP_NAME(curs_set) (NCURSES_SP_ARGx cursor);
321 _nc_mvcur_resume(void)
323 NCURSES_SP_NAME(_nc_mvcur_resume) (CURRENT_SCREEN);
328 NCURSES_SP_NAME(_nc_mvcur_init) (NCURSES_SP_DCL0)
329 /* initialize the cost structure */
331 if (SP_PARM->_ofp && NC_ISATTY(fileno(SP_PARM->_ofp))) {
332 SP_PARM->_char_padding = ((BAUDBYTE * 1000 * 10)
333 / (BAUDRATE(SP_PARM) > 0
337 SP_PARM->_char_padding = 1; /* must be nonzero */
339 if (SP_PARM->_char_padding <= 0)
340 SP_PARM->_char_padding = 1; /* must be nonzero */
341 TR(TRACE_CHARPUT | TRACE_MOVE, ("char_padding %d msecs", SP_PARM->_char_padding));
343 /* non-parameterized local-motion strings */
344 SP_PARM->_cr_cost = CostOf(carriage_return, 0);
345 SP_PARM->_home_cost = CostOf(cursor_home, 0);
346 SP_PARM->_ll_cost = CostOf(cursor_to_ll, 0);
348 if (getenv("NCURSES_NO_HARD_TABS") == 0
349 && dest_tabs_magic_smso == 0
351 SP_PARM->_ht_cost = CostOf(tab, 0);
352 SP_PARM->_cbt_cost = CostOf(back_tab, 0);
354 SP_PARM->_ht_cost = INFINITY;
355 SP_PARM->_cbt_cost = INFINITY;
357 #endif /* USE_HARD_TABS */
358 SP_PARM->_cub1_cost = CostOf(cursor_left, 0);
359 SP_PARM->_cuf1_cost = CostOf(cursor_right, 0);
360 SP_PARM->_cud1_cost = CostOf(cursor_down, 0);
361 SP_PARM->_cuu1_cost = CostOf(cursor_up, 0);
363 SP_PARM->_smir_cost = CostOf(enter_insert_mode, 0);
364 SP_PARM->_rmir_cost = CostOf(exit_insert_mode, 0);
365 SP_PARM->_ip_cost = 0;
366 if (insert_padding) {
367 SP_PARM->_ip_cost = CostOf(insert_padding, 0);
371 * Assumption: if the terminal has memory_relative addressing, the
372 * initialization strings or smcup will set single-page mode so we
373 * can treat it like absolute screen addressing. This seems to be true
374 * for all cursor_mem_address terminal types in the terminfo database.
376 SP_PARM->_address_cursor = cursor_address ? cursor_address : cursor_mem_address;
379 * Parametrized local-motion strings. This static cost computation
380 * depends on the following assumptions:
382 * (1) They never have * padding. In the entire master terminfo database
383 * as of March 1995, only the obsolete Zenith Z-100 pc violates this.
384 * (Proportional padding is found mainly in insert, delete and scroll
387 * (2) The average case of cup has two two-digit parameters. Strictly,
388 * the average case for a 24 * 80 screen has ((10*10*(1 + 1)) +
389 * (14*10*(1 + 2)) + (10*70*(2 + 1)) + (14*70*4)) / (24*80) = 3.458
390 * digits of parameters. On a 25x80 screen the average is 3.6197.
391 * On larger screens the value gets much closer to 4.
393 * (3) The average case of cub/cuf/hpa/ech/rep has 2 digits of parameters
394 * (strictly, (((10 * 1) + (70 * 2)) / 80) = 1.8750).
396 * (4) The average case of cud/cuu/vpa has 2 digits of parameters
397 * (strictly, (((10 * 1) + (14 * 2)) / 24) = 1.5833).
399 * All these averages depend on the assumption that all parameter values
400 * are equally probable.
402 SP_PARM->_cup_cost = CostOf(TIPARM_2(SP_PARM->_address_cursor, 23, 23), 1);
403 SP_PARM->_cub_cost = CostOf(TIPARM_1(parm_left_cursor, 23), 1);
404 SP_PARM->_cuf_cost = CostOf(TIPARM_1(parm_right_cursor, 23), 1);
405 SP_PARM->_cud_cost = CostOf(TIPARM_1(parm_down_cursor, 23), 1);
406 SP_PARM->_cuu_cost = CostOf(TIPARM_1(parm_up_cursor, 23), 1);
407 SP_PARM->_hpa_cost = CostOf(TIPARM_1(column_address, 23), 1);
408 SP_PARM->_vpa_cost = CostOf(TIPARM_1(row_address, 23), 1);
410 /* non-parameterized screen-update strings */
411 SP_PARM->_ed_cost = NormalizedCost(clr_eos, 1);
412 SP_PARM->_el_cost = NormalizedCost(clr_eol, 1);
413 SP_PARM->_el1_cost = NormalizedCost(clr_bol, 1);
414 SP_PARM->_dch1_cost = NormalizedCost(delete_character, 1);
415 SP_PARM->_ich1_cost = NormalizedCost(insert_character, 1);
418 * If this is a bce-terminal, we want to bias the choice so we use clr_eol
419 * rather than spaces at the end of a line.
421 if (back_color_erase)
422 SP_PARM->_el_cost = 0;
424 /* parameterized screen-update strings */
425 SP_PARM->_dch_cost = NormalizedCost(TIPARM_1(parm_dch, 23), 1);
426 SP_PARM->_ich_cost = NormalizedCost(TIPARM_1(parm_ich, 23), 1);
427 SP_PARM->_ech_cost = NormalizedCost(TIPARM_1(erase_chars, 23), 1);
428 SP_PARM->_rep_cost = NormalizedCost(TIPARM_2(repeat_char, ' ', 23), 1);
430 SP_PARM->_cup_ch_cost = NormalizedCost(TIPARM_2(SP_PARM->_address_cursor,
433 SP_PARM->_hpa_ch_cost = NormalizedCost(TIPARM_1(column_address, 23), 1);
434 SP_PARM->_cuf_ch_cost = NormalizedCost(TIPARM_1(parm_right_cursor, 23), 1);
435 SP_PARM->_inline_cost = min(SP_PARM->_cup_ch_cost,
436 min(SP_PARM->_hpa_ch_cost,
437 SP_PARM->_cuf_ch_cost));
440 * If save_cursor is used within enter_ca_mode, we should not use it for
441 * scrolling optimization, since the corresponding restore_cursor is not
442 * nested on the various terminals (vt100, xterm, etc.) which use this
446 && enter_ca_mode != 0
447 && strstr(enter_ca_mode, save_cursor) != 0) {
448 T(("...suppressed sc/rc capability due to conflict with smcup/rmcup"));
454 * A different, possibly better way to arrange this would be to set the
455 * SCREEN's _endwin at window initialization time and let this be called by
456 * doupdate's return-from-shellout code.
458 NCURSES_SP_NAME(_nc_mvcur_resume) (NCURSES_SP_ARG);
465 NCURSES_SP_NAME(_nc_mvcur_init) (CURRENT_SCREEN);
470 NCURSES_SP_NAME(_nc_mvcur_wrap) (NCURSES_SP_DCL0)
471 /* wrap up cursor-addressing mode */
473 /* leave cursor at screen bottom */
474 TINFO_MVCUR(NCURSES_SP_ARGx -1, -1, screen_lines(SP_PARM) - 1, 0);
476 if (!SP_PARM || !IsTermInfo(SP_PARM))
479 /* set cursor to normal mode */
480 if (SP_PARM->_cursor != -1) {
481 int cursor = SP_PARM->_cursor;
482 NCURSES_SP_NAME(curs_set) (NCURSES_SP_ARGx 1);
483 SP_PARM->_cursor = cursor;
487 NCURSES_PUTP2("exit_ca_mode", exit_ca_mode);
490 * Reset terminal's tab counter. There's a long-time bug that
491 * if you exit a "curses" program such as vi or more, tab
492 * forward, and then backspace, the cursor doesn't go to the
493 * right place. The problem is that the kernel counts the
494 * escape sequences that reset things as column positions.
495 * Utter a \r to reset this invisibly.
497 NCURSES_SP_NAME(_nc_outch) (NCURSES_SP_ARGx '\r');
504 NCURSES_SP_NAME(_nc_mvcur_wrap) (CURRENT_SCREEN);
508 /****************************************************************************
510 * Optimized cursor movement
512 ****************************************************************************/
515 * Perform repeated-append, returning cost
517 static NCURSES_INLINE int
518 repeated_append(string_desc * target, int total, int num, int repeat, const char *src)
520 size_t need = (size_t) repeat * strlen(src);
522 if (need < target->s_size) {
523 while (repeat-- > 0) {
524 if (_nc_safe_strcat(target, src)) {
538 #define NEXTTAB(fr) (fr + init_tabs - (fr % init_tabs))
541 * Assume back_tab (CBT) does not wrap backwards at the left margin, return
542 * a negative value at that point to simplify the loop.
544 #define LASTTAB(fr) ((fr > 0) ? ((fr - 1) / init_tabs) * init_tabs : -1)
547 relative_move(NCURSES_SP_DCLx
548 string_desc * target,
554 /* move via local motions (cuu/cuu1/cud/cud1/cub1/cub/cuf1/cuf/vpa/hpa) */
557 int n, vcost = 0, hcost = 0;
559 (void) _nc_str_copy(&save, target);
561 if (to_y != from_y) {
565 && _nc_safe_strcat(target, TIPARM_1(row_address, to_y))) {
566 vcost = SP_PARM->_vpa_cost;
573 && SP_PARM->_cud_cost < vcost
574 && _nc_safe_strcat(_nc_str_copy(target, &save),
575 TIPARM_1(parm_down_cursor, n))) {
576 vcost = SP_PARM->_cud_cost;
580 && (*cursor_down != '\n')
581 && (n * SP_PARM->_cud1_cost < vcost)) {
582 vcost = repeated_append(_nc_str_copy(target, &save), 0,
583 SP_PARM->_cud1_cost, n, cursor_down);
585 } else { /* (to_y < from_y) */
589 && SP_PARM->_cuu_cost < vcost
590 && _nc_safe_strcat(_nc_str_copy(target, &save),
591 TIPARM_1(parm_up_cursor, n))) {
592 vcost = SP_PARM->_cuu_cost;
595 if (cursor_up && (n * SP_PARM->_cuu1_cost < vcost)) {
596 vcost = repeated_append(_nc_str_copy(target, &save), 0,
597 SP_PARM->_cuu1_cost, n, cursor_up);
601 if (vcost == INFINITY)
607 if (to_x != from_x) {
614 && _nc_safe_strcat(_nc_str_copy(target, &save),
615 TIPARM_1(column_address, to_x))) {
616 hcost = SP_PARM->_hpa_cost;
622 if (parm_right_cursor
623 && SP_PARM->_cuf_cost < hcost
624 && _nc_safe_strcat(_nc_str_copy(target, &save),
625 TIPARM_1(parm_right_cursor, n))) {
626 hcost = SP_PARM->_cuf_cost;
632 (void) _nc_str_init(&check, str, sizeof(str));
635 /* use hard tabs, if we have them, to do as much as possible */
636 if (init_tabs > 0 && tab) {
639 for (fr = from_x; (nxt = NEXTTAB(fr)) <= to_x; fr = nxt) {
640 lhcost = repeated_append(&check, lhcost,
641 SP_PARM->_ht_cost, 1, tab);
642 if (lhcost == INFINITY)
649 #endif /* USE_HARD_TABS */
651 if (n <= 0 || n >= (int) check.s_size)
655 * If we're allowing BSD-style padding in tputs, don't generate
656 * a string with a leading digit. Otherwise, that will be
657 * interpreted as a padding value rather than sent to the
662 && n < (int) check.s_size
665 int wanted = CharOf(WANT_CHAR(SP_PARM, to_y, from_x));
666 if (is8bits(wanted) && isdigit(wanted))
671 * If we have no attribute changes, overwrite is cheaper.
672 * Note: must suppress this by passing in ovw = FALSE whenever
673 * WANT_CHAR would return invalid data. In particular, this
674 * is true between the time a hardware scroll has been done
675 * and the time the structure WANT_CHAR would access has been
681 for (i = 0; i < n; i++) {
682 NCURSES_CH_T ch = WANT_CHAR(SP_PARM, to_y, from_x + i);
683 if (!SameAttrOf(ch, SCREEN_ATTRS(SP_PARM))
684 #if USE_WIDEC_SUPPORT
696 for (i = 0; i < n; i++)
697 *check.s_tail++ = (char) CharOf(WANT_CHAR(SP_PARM, to_y,
699 *check.s_tail = '\0';
700 check.s_size -= (size_t) n;
701 lhcost += n * SP_PARM->_char_padding;
703 lhcost = repeated_append(&check, lhcost, SP_PARM->_cuf1_cost,
708 && _nc_safe_strcat(_nc_str_copy(target, &save), str)) {
712 } else { /* (to_x < from_x) */
716 && SP_PARM->_cub_cost < hcost
717 && _nc_safe_strcat(_nc_str_copy(target, &save),
718 TIPARM_1(parm_left_cursor, n))) {
719 hcost = SP_PARM->_cub_cost;
725 (void) _nc_str_init(&check, str, sizeof(str));
728 if (init_tabs > 0 && back_tab) {
731 for (fr = from_x; (nxt = LASTTAB(fr)) >= to_x; fr = nxt) {
732 lhcost = repeated_append(&check, lhcost,
735 if (lhcost == INFINITY)
741 #endif /* USE_HARD_TABS */
743 lhcost = repeated_append(&check, lhcost,
748 && _nc_safe_strcat(_nc_str_copy(target, &save), str)) {
754 if (hcost == INFINITY)
758 return (vcost + hcost);
760 #endif /* !NO_OPTIMIZE */
763 * With the machinery set up above, it's conceivable that
764 * onscreen_mvcur could be modified into a recursive function that does
765 * an alpha-beta search of motion space, as though it were a chess
766 * move tree, with the weight function being boolean and the search
767 * depth equated to length of string. However, this would jack up the
768 * computation cost a lot, especially on terminals without a cup
769 * capability constraining the search tree depth. So we settle for
770 * the simpler method below.
773 static NCURSES_INLINE int
774 onscreen_mvcur(NCURSES_SP_DCLx
776 int ynew, int xnew, int ovw,
777 NCURSES_SP_OUTC myOutCh)
778 /* onscreen move from (yold, xold) to (ynew, xnew) */
781 char buffer[OPT_SIZE];
782 int tactic = 0, newcost, usecost = INFINITY;
785 #if defined(MAIN) || defined(NCURSES_TEST)
786 struct timeval before, after;
788 gettimeofday(&before, NULL);
791 #define NullResult _nc_str_null(&result, sizeof(buffer))
792 #define InitResult _nc_str_init(&result, buffer, sizeof(buffer))
794 /* tactic #0: use direct cursor addressing */
795 if (_nc_safe_strcpy(InitResult, TIPARM_2(SP_PARM->_address_cursor,
798 usecost = SP_PARM->_cup_cost;
800 #if defined(TRACE) || defined(NCURSES_TEST)
801 if (!(_nc_optimize_enable & OPTIMIZE_MVCUR))
806 * We may be able to tell in advance that the full optimization
807 * will probably not be worth its overhead. Also, don't try to
808 * use local movement if the current attribute is anything but
809 * A_NORMAL...there are just too many ways this can screw up
810 * (like, say, local-movement \n getting mapped to some obscure
811 * character because A_ALTCHARSET is on).
813 if (yold == -1 || xold == -1 || NOT_LOCAL(SP_PARM, yold, xold, ynew, xnew)) {
814 #if defined(MAIN) || defined(NCURSES_TEST)
816 (void) fputs("nonlocal\n", stderr);
817 goto nonlocal; /* always run the optimizer if profiling */
825 /* tactic #1: use local movement */
826 if (yold != -1 && xold != -1
827 && ((newcost = relative_move(NCURSES_SP_ARGx
830 ynew, xnew, ovw)) != INFINITY)
831 && newcost < usecost) {
836 /* tactic #2: use carriage-return + local movement */
837 if (yold != -1 && carriage_return
838 && ((newcost = relative_move(NCURSES_SP_ARGx
841 ynew, xnew, ovw)) != INFINITY)
842 && SP_PARM->_cr_cost + newcost < usecost) {
844 usecost = SP_PARM->_cr_cost + newcost;
847 /* tactic #3: use home-cursor + local movement */
849 && ((newcost = relative_move(NCURSES_SP_ARGx
852 ynew, xnew, ovw)) != INFINITY)
853 && SP_PARM->_home_cost + newcost < usecost) {
855 usecost = SP_PARM->_home_cost + newcost;
858 /* tactic #4: use home-down + local movement */
860 && ((newcost = relative_move(NCURSES_SP_ARGx
862 screen_lines(SP_PARM) - 1, 0,
863 ynew, xnew, ovw)) != INFINITY)
864 && SP_PARM->_ll_cost + newcost < usecost) {
866 usecost = SP_PARM->_ll_cost + newcost;
870 * tactic #5: use left margin for wrap to right-hand side,
871 * unless strange wrap behavior indicated by xenl might hose us.
873 t5_cr_cost = (xold > 0 ? SP_PARM->_cr_cost : 0);
874 if (auto_left_margin && !eat_newline_glitch
875 && yold > 0 && cursor_left
876 && ((newcost = relative_move(NCURSES_SP_ARGx
878 yold - 1, screen_columns(SP_PARM) - 1,
879 ynew, xnew, ovw)) != INFINITY)
880 && t5_cr_cost + SP_PARM->_cub1_cost + newcost < usecost) {
882 usecost = t5_cr_cost + SP_PARM->_cub1_cost + newcost;
886 * These cases are ordered by estimated relative frequency.
892 (void) relative_move(NCURSES_SP_ARGx
898 (void) _nc_safe_strcpy(&result, carriage_return);
899 (void) relative_move(NCURSES_SP_ARGx
905 (void) _nc_safe_strcpy(&result, cursor_home);
906 (void) relative_move(NCURSES_SP_ARGx
911 (void) _nc_safe_strcpy(&result, cursor_to_ll);
912 (void) relative_move(NCURSES_SP_ARGx
914 screen_lines(SP_PARM) - 1, 0,
919 (void) _nc_safe_strcat(&result, carriage_return);
920 (void) _nc_safe_strcat(&result, cursor_left);
921 (void) relative_move(NCURSES_SP_ARGx
923 yold - 1, screen_columns(SP_PARM) - 1,
927 #endif /* !NO_OPTIMIZE */
930 #if defined(MAIN) || defined(NCURSES_TEST)
931 gettimeofday(&after, NULL);
932 diff = after.tv_usec - before.tv_usec
933 + (after.tv_sec - before.tv_sec) * 1000000;
935 (void) fprintf(stderr,
936 "onscreen: %d microsec, %f 28.8Kbps char-equivalents\n",
937 (int) diff, diff / 288);
940 if (usecost != INFINITY) {
941 TR(TRACE_MOVE, ("mvcur tactic %d", tactic));
942 TPUTS_TRACE("mvcur");
943 NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx
945 SP_PARM->_cursrow = ynew;
946 SP_PARM->_curscol = xnew;
953 * optimized cursor move from (yold, xold) to (ynew, xnew)
956 _nc_real_mvcur(NCURSES_SP_DCLx
959 NCURSES_SP_OUTC myOutCh,
962 NCURSES_CH_T oldattr;
965 TR(TRACE_CALLS | TRACE_MOVE, (T_CALLED("_nc_real_mvcur(%p,%d,%d,%d,%d)"),
966 (void *) SP_PARM, yold, xold, ynew, xnew));
970 } else if (yold == ynew && xold == xnew) {
975 * Most work here is rounding for terminal boundaries getting the
976 * column position implied by wraparound or the lack thereof and
977 * rolling up the screen to get ynew on the screen.
979 if (xnew >= screen_columns(SP_PARM)) {
980 ynew += xnew / screen_columns(SP_PARM);
981 xnew %= screen_columns(SP_PARM);
985 * Force restore even if msgr is on when we're in an alternate
986 * character set -- these have a strong tendency to screw up the CR &
987 * LF used for local character motions!
989 oldattr = SCREEN_ATTRS(SP_PARM);
990 if ((AttrOf(oldattr) & A_ALTCHARSET)
991 || (AttrOf(oldattr) && !move_standout_mode)) {
992 TR(TRACE_CHARPUT, ("turning off (%#lx) %s before move",
993 (unsigned long) AttrOf(oldattr),
994 _traceattr(AttrOf(oldattr))));
995 VIDPUTS(SP_PARM, A_NORMAL, 0);
998 if (xold >= screen_columns(SP_PARM)) {
1000 int l = (xold + 1) / screen_columns(SP_PARM);
1003 if (yold >= screen_lines(SP_PARM))
1004 l -= (yold - screen_lines(SP_PARM) - 1);
1007 if (carriage_return) {
1008 NCURSES_PUTP2("carriage_return", carriage_return);
1010 myOutCh(NCURSES_SP_ARGx '\r');
1016 NCURSES_PUTP2("newline", newline);
1018 myOutCh(NCURSES_SP_ARGx '\n');
1025 if (yold > screen_lines(SP_PARM) - 1)
1026 yold = screen_lines(SP_PARM) - 1;
1027 if (ynew > screen_lines(SP_PARM) - 1)
1028 ynew = screen_lines(SP_PARM) - 1;
1030 /* destination location is on screen now */
1031 code = onscreen_mvcur(NCURSES_SP_ARGx yold, xold, ynew, xnew, ovw, myOutCh);
1034 * Restore attributes if we disabled them before moving.
1036 if (!SameAttrOf(oldattr, SCREEN_ATTRS(SP_PARM))) {
1037 TR(TRACE_CHARPUT, ("turning on (%#lx) %s after move",
1038 (unsigned long) AttrOf(oldattr),
1039 _traceattr(AttrOf(oldattr))));
1040 VIDPUTS(SP_PARM, AttrOf(oldattr), GetPair(oldattr));
1047 * These entrypoints are used within the library.
1050 NCURSES_SP_NAME(_nc_mvcur) (NCURSES_SP_DCLx
1055 rc = _nc_real_mvcur(NCURSES_SP_ARGx yold, xold, ynew, xnew,
1056 NCURSES_SP_NAME(_nc_outch),
1059 * With the terminal-driver, we cannot distinguish between internal and
1060 * external calls. Flush the output if the screen has not been
1061 * initialized, e.g., when used from low-level terminfo programs.
1063 if ((SP_PARM != 0) && (SP_PARM->_endwin == ewInitial))
1064 NCURSES_SP_NAME(_nc_flush) (NCURSES_SP_ARG);
1068 #if NCURSES_SP_FUNCS
1070 _nc_mvcur(int yold, int xold,
1073 return NCURSES_SP_NAME(_nc_mvcur) (CURRENT_SCREEN, yold, xold, ynew, xnew);
1077 #if defined(USE_TERM_DRIVER)
1079 * The terminal driver does not support the external "mvcur()".
1082 TINFO_MVCUR(NCURSES_SP_DCLx int yold, int xold, int ynew, int xnew)
1085 rc = _nc_real_mvcur(NCURSES_SP_ARGx
1088 NCURSES_SP_NAME(_nc_outch),
1090 if ((SP_PARM != 0) && (SP_PARM->_endwin == ewInitial))
1091 NCURSES_SP_NAME(_nc_flush) (NCURSES_SP_ARG);
1092 NCURSES_SP_NAME(_nc_flush) (NCURSES_SP_ARG);
1096 #else /* !USE_TERM_DRIVER */
1099 * These entrypoints support users of the library.
1102 NCURSES_SP_NAME(mvcur) (NCURSES_SP_DCLx int yold, int xold, int ynew,
1105 return _nc_real_mvcur(NCURSES_SP_ARGx
1108 NCURSES_SP_NAME(_nc_putchar),
1112 #if NCURSES_SP_FUNCS
1114 mvcur(int yold, int xold, int ynew, int xnew)
1116 return NCURSES_SP_NAME(mvcur) (CURRENT_SCREEN, yold, xold, ynew, xnew);
1119 #endif /* USE_TERM_DRIVER */
1121 #if defined(TRACE) || defined(NCURSES_TEST)
1122 NCURSES_EXPORT_VAR(int) _nc_optimize_enable = OPTIMIZE_ALL;
1125 #if defined(MAIN) || defined(NCURSES_TEST)
1126 /****************************************************************************
1128 * Movement optimizer test code
1130 ****************************************************************************/
1133 #include <dump_entry.h>
1136 NCURSES_EXPORT_VAR(const char *) _nc_progname = "mvcur";
1138 static unsigned long xmits;
1140 /* these override lib_tputs.c */
1142 tputs(const char *string, int affcnt GCC_UNUSED, int (*outc) (int) GCC_UNUSED)
1143 /* stub tputs() that dumps sequences in a visible form */
1146 xmits += strlen(string);
1148 (void) fputs(_nc_visbuf(string), stdout);
1153 putp(const char *string)
1155 return (tputs(string, 1, _nc_outch));
1166 delay_output(int ms GCC_UNUSED)
1171 static char tname[PATH_MAX];
1176 (void) setupterm(tname, STDOUT_FILENO, NULL);
1184 i = (RAND_MAX / n) * n;
1185 while ((j = rand()) >= i)
1191 main(int argc GCC_UNUSED, char *argv[]GCC_UNUSED)
1193 _nc_STRCPY(tname, getenv("TERM"), sizeof(tname));
1195 _nc_setupscreen(lines, columns, stdout, FALSE, 0);
1200 (void) puts("The mvcur tester. Type ? for help");
1202 fputs("smcup:", stdout);
1206 int fy, fx, ty, tx, n, i;
1207 char buf[BUFSIZ], capname[BUFSIZ];
1209 if (fputs("> ", stdout) == EOF)
1211 if (fgets(buf, sizeof(buf), stdin) == 0)
1214 #define PUTS(s) (void) puts(s)
1215 #define PUTF(s,t) (void) printf(s,t)
1216 if (buf[0] == '?') {
1217 PUTS("? -- display this help message");
1218 PUTS("fy fx ty tx -- (4 numbers) display (fy,fx)->(ty,tx) move");
1219 PUTS("s[croll] n t b m -- display scrolling sequence");
1220 PUTF("r[eload] -- reload terminal info for %s\n",
1222 PUTS("l[oad] <term> -- load terminal info for type <term>");
1223 PUTS("d[elete] <cap> -- delete named capability");
1224 PUTS("i[nspect] -- display terminal capabilities");
1225 PUTS("c[ost] -- dump cursor-optimization cost table");
1226 PUTS("o[optimize] -- toggle movement optimization");
1227 PUTS("t[orture] <num> -- torture-test with <num> random moves");
1228 PUTS("q[uit] -- quit the program");
1229 } else if (sscanf(buf, "%d %d %d %d", &fy, &fx, &ty, &tx) == 4) {
1230 struct timeval before, after;
1234 gettimeofday(&before, NULL);
1235 mvcur(fy, fx, ty, tx);
1236 gettimeofday(&after, NULL);
1238 printf("\" (%ld msec)\n",
1239 (long) (after.tv_usec - before.tv_usec
1240 + (after.tv_sec - before.tv_sec)
1242 } else if (sscanf(buf, "s %d %d %d %d", &fy, &fx, &ty, &tx) == 4) {
1243 struct timeval before, after;
1247 gettimeofday(&before, NULL);
1248 _nc_scrolln(fy, fx, ty, tx);
1249 gettimeofday(&after, NULL);
1251 printf("\" (%ld msec)\n",
1252 (long) (after.tv_usec - before.tv_usec + (after.tv_sec -
1255 } else if (buf[0] == 'r') {
1256 _nc_STRCPY(tname, termname(), sizeof(tname));
1258 } else if (sscanf(buf, "l %s", tname) == 1) {
1260 } else if (sscanf(buf, "d %s", capname) == 1) {
1261 struct name_table_entry const *np = _nc_find_entry(capname,
1262 _nc_get_hash_table(FALSE));
1265 (void) printf("No such capability as \"%s\"\n", capname);
1267 switch (np->nte_type) {
1269 cur_term->type.Booleans[np->nte_index] = FALSE;
1271 printf("Boolean capability `%s' (%d) turned off.\n",
1272 np->nte_name, np->nte_index);
1276 cur_term->type.Numbers[np->nte_index] = ABSENT_NUMERIC;
1277 (void) printf("Number capability `%s' (%d) set to -1.\n",
1278 np->nte_name, np->nte_index);
1282 cur_term->type.Strings[np->nte_index] = ABSENT_STRING;
1283 (void) printf("String capability `%s' (%d) deleted.\n",
1284 np->nte_name, np->nte_index);
1288 } else if (buf[0] == 'i') {
1289 dump_init(NULL, F_TERMINFO, S_TERMINFO,
1290 FALSE, 70, 0, 0, FALSE, FALSE, 0);
1291 dump_entry(&TerminalType(cur_term), FALSE, TRUE, 0, 0);
1293 } else if (buf[0] == 'o') {
1294 if (_nc_optimize_enable & OPTIMIZE_MVCUR) {
1295 _nc_optimize_enable &= ~OPTIMIZE_MVCUR;
1296 (void) puts("Optimization is now off.");
1298 _nc_optimize_enable |= OPTIMIZE_MVCUR;
1299 (void) puts("Optimization is now on.");
1303 * You can use the `t' test to profile and tune the movement
1304 * optimizer. Use iteration values in three digits or more.
1305 * At above 5000 iterations the profile timing averages are stable
1306 * to within a millisecond or three.
1308 * The `overhead' field of the report will help you pick a
1309 * COMPUTE_OVERHEAD figure appropriate for your processor and
1310 * expected line speed. The `total estimated time' is
1311 * computation time plus a character-transmission time
1312 * estimate computed from the number of transmits and the baud
1315 * Use this together with the `o' command to get a read on the
1316 * optimizer's effectiveness. Compare the total estimated times
1317 * for `t' runs of the same length in both optimized and un-optimized
1318 * modes. As long as the optimized times are less, the optimizer
1321 else if (sscanf(buf, "t %d", &n) == 1) {
1322 float cumtime = 0.0, perchar;
1324 {2400, 9600, 14400, 19200, 28800, 38400, 0};
1326 srand((unsigned) (getpid() + time((time_t *) 0)));
1329 for (i = 0; i < n; i++) {
1331 * This does a move test between two random locations,
1332 * Random moves probably short-change the optimizer,
1333 * which will work better on the short moves probably
1334 * typical of doupdate()'s usage pattern. Still,
1335 * until we have better data...
1337 #ifdef FIND_COREDUMP
1338 int from_y = roll(lines);
1339 int to_y = roll(lines);
1340 int from_x = roll(columns);
1341 int to_x = roll(columns);
1343 printf("(%d,%d) -> (%d,%d)\n", from_y, from_x, to_y, to_x);
1344 mvcur(from_y, from_x, to_y, to_x);
1346 mvcur(roll(lines), roll(columns), roll(lines), roll(columns));
1347 #endif /* FIND_COREDUMP */
1354 * Average milliseconds per character optimization time.
1355 * This is the key figure to watch when tuning the optimizer.
1357 perchar = cumtime / n;
1359 (void) printf("%d moves (%ld chars) in %d msec, %f msec each:\n",
1360 n, xmits, (int) cumtime, perchar);
1362 for (i = 0; speeds[i]; i++) {
1364 * Total estimated time for the moves, computation and
1365 * transmission both. Transmission time is an estimate
1366 * assuming 9 bits/char, 8 bits + 1 stop bit.
1368 float totalest = cumtime + xmits * 9 * 1e6 / speeds[i];
1371 * Per-character optimization overhead in character transmits
1372 * at the current speed. Round this to the nearest integer
1373 * to figure COMPUTE_OVERHEAD for the speed.
1375 float overhead = speeds[i] * perchar / 1e6;
1378 printf("%6d bps: %3.2f char-xmits overhead; total estimated time %15.2f\n",
1379 speeds[i], overhead, totalest);
1381 } else if (buf[0] == 'c') {
1382 (void) printf("char padding: %d\n", CURRENT_SCREEN->_char_padding);
1383 (void) printf("cr cost: %d\n", CURRENT_SCREEN->_cr_cost);
1384 (void) printf("cup cost: %d\n", CURRENT_SCREEN->_cup_cost);
1385 (void) printf("home cost: %d\n", CURRENT_SCREEN->_home_cost);
1386 (void) printf("ll cost: %d\n", CURRENT_SCREEN->_ll_cost);
1388 (void) printf("ht cost: %d\n", CURRENT_SCREEN->_ht_cost);
1389 (void) printf("cbt cost: %d\n", CURRENT_SCREEN->_cbt_cost);
1390 #endif /* USE_HARD_TABS */
1391 (void) printf("cub1 cost: %d\n", CURRENT_SCREEN->_cub1_cost);
1392 (void) printf("cuf1 cost: %d\n", CURRENT_SCREEN->_cuf1_cost);
1393 (void) printf("cud1 cost: %d\n", CURRENT_SCREEN->_cud1_cost);
1394 (void) printf("cuu1 cost: %d\n", CURRENT_SCREEN->_cuu1_cost);
1395 (void) printf("cub cost: %d\n", CURRENT_SCREEN->_cub_cost);
1396 (void) printf("cuf cost: %d\n", CURRENT_SCREEN->_cuf_cost);
1397 (void) printf("cud cost: %d\n", CURRENT_SCREEN->_cud_cost);
1398 (void) printf("cuu cost: %d\n", CURRENT_SCREEN->_cuu_cost);
1399 (void) printf("hpa cost: %d\n", CURRENT_SCREEN->_hpa_cost);
1400 (void) printf("vpa cost: %d\n", CURRENT_SCREEN->_vpa_cost);
1401 } else if (buf[0] == 'x' || buf[0] == 'q')
1404 (void) puts("Invalid command.");
1407 (void) fputs("rmcup:", stdout);
1416 /* lib_mvcur.c ends here */