Install ncurses as -lcurses and <curses.h>

Install BSD curses library as -locurses and <ocurses.h>

1 files changed, 1389 insertions, 0 deletions

diff --git a/lib/libcurses/lib_mvcur.c b/lib/libcurses/lib_mvcur.c
new file mode 100644
index 00000000000..b8483e95480
--- /dev/null
+++ b/lib/libcurses/lib_mvcur.c
@@ -0,0 +1,1389 @@
+
+/***************************************************************************
+*                            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_mvcur.c
+**
+**	The routines for moving the physical cursor and scrolling:
+**
+**		void _nc_mvcur_init(void), mvcur_wrap(void)
+**
+**		int mvcur(int old_y, int old_x, int new_y, int new_x)
+**
+**		void _nc_mvcur_wrap(void)
+**
+**		int _nc_mvcur_scrolln(int n, int top, int bot, int maxy)
+**
+** Comparisons with older movement optimizers:  
+**    SVr3 curses mvcur() can't use cursor_to_ll or auto_left_margin.
+**    4.4BSD curses can't use cuu/cud/cuf/cub/hpa/vpa/tab/cbt for local
+** motions.  It doesn't use tactics based on auto_left_margin.  Weirdly
+** enough, it doesn't use its own hardware-scrolling routine to scroll up
+** destination lines for out-of-bounds addresses!
+**    old ncurses optimizer: less accurate cost computations (in fact,
+** it was broken and had to be commented out!).
+**
+** Compile with -DMAIN to build an interactive tester/timer for the movement
+** optimizer.  You can use it to investigate the optimizer's behavior.
+** You can also use it for tuning the formulas used to determine whether
+** or not full optimization is attempted.
+**
+** This code has a nasty tendency to find bugs in terminfo entries, because it
+** exercises the non-cup movement capabilities heavily.  If you think you've
+** found a bug, try deleting subsets of the following capabilities (arranged
+** in decreasing order of suspiciousness): it, tab, cbt, hpa, vpa, cuu, cud,
+** cuf, cub, cuu1, cud1, cuf1, cub1.  It may be that one or more are wrong.
+**
+** Note: you should expect this code to look like a resource hog in a profile.
+** That's because it does a lot of I/O, through the tputs() calls.  The I/O 
+** cost swamps the computation overhead (and as machines get faster, this
+** will become even more true).  Comments in the test exerciser at the end
+** go into detail about tuning and how you can gauge the optimizer's
+** effectiveness.
+**/
+
+/****************************************************************************
+ *
+ * Constants and macros for optimizer tuning.
+ *
+ ****************************************************************************/
+
+/*
+ * The average overhead of a full optimization computation in character
+ * transmission times.  If it's too high, the algorithm will be a bit
+ * over-biased toward using cup rather than local motions; if it's too
+ * low, the algorithm may spend more time than is strictly optimal
+ * looking for non-cup motions.  Profile the optimizer using the `t'
+ * command of the exerciser (see below), and round to the nearest integer.
+ *
+ * Yes, I (esr) thought about computing expected overhead dynamically, say
+ * by derivation from a running average of optimizer times.  But the
+ * whole point of this optimization is to *decrease* the frequency of
+ * system calls. :-)
+ */
+#define COMPUTE_OVERHEAD	1	/* I use a 90MHz Pentium @ 9.6Kbps */
+
+/*
+ * LONG_DIST is the distance we consider to be just as costly to move over as a
+ * cup sequence is to emit.  In other words, it's the length of a cup sequence
+ * adjusted for average computation overhead.  The magic number is the length
+ * of "\033[yy;xxH", the typical cup sequence these days.
+ */
+#define LONG_DIST		(8 - COMPUTE_OVERHEAD)
+
+/*
+ * Tell whether a motion is optimizable by local motions.  Needs to be cheap to
+ * compute. In general, all the fast moves go to either the right or left edge
+ * of the screen.  So any motion to a location that is (a) further away than
+ * LONG_DIST and (b) further inward from the right or left edge than LONG_DIST,
+ * we'll consider nonlocal.
+ */
+#define NOT_LOCAL(fy, fx, ty, tx)	((tx > LONG_DIST) && (tx < screen_lines - 1 - LONG_DIST) && (abs(ty-fy) + abs(tx-fx) > LONG_DIST))
+
+/****************************************************************************
+ *
+ * External interfaces
+ *
+ ****************************************************************************/
+
+/*
+ * For this code to work OK, the following components must live in the
+ * screen structure:
+ *
+ *	int		_char_padding;	// cost of character put
+ *	int		_cr_cost;	// cost of (carriage_return)
+ *	int		_cup_cost;	// cost of (cursor_address)
+ *	int		_home_cost;	// cost of (cursor_home)
+ *	int		_ll_cost;	// cost of (cursor_to_ll)
+ *#ifdef TABS_OK
+ *	int		_ht_cost;	// cost of (tab)
+ *	int		_cbt_cost;	// cost of (backtab)
+ *#endif TABS_OK
+ *	int		_cub1_cost;	// cost of (cursor_left)
+ *	int		_cuf1_cost;	// cost of (cursor_right)
+ *	int		_cud1_cost;	// cost of (cursor_down)
+ *	int		_cuu1_cost;	// cost of (cursor_up)
+ *	int		_cub_cost;	// cost of (parm_cursor_left)
+ *	int		_cuf_cost;	// cost of (parm_cursor_right)
+ *	int		_cud_cost;	// cost of (parm_cursor_down)
+ *	int		_cuu_cost;	// cost of (parm_cursor_up)
+ *	int		_hpa_cost;	// cost of (column_address)
+ *	int		_vpa_cost;	// cost of (row_address)
+ *
+ * The TABS_OK switch controls whether it is reliable to use tab/backtabs
+ * for local motions.  On many systems, it's not, due to uncertainties about
+ * tab delays and whether or not tabs will be expanded in raw mode.  If you
+ * have parm_right_cursor, tab motions don't win you a lot anyhow.
+ */
+
+#include "curses.priv.h"
+#include "term.h"
+
+#define NLMAPPING	SP->_nl			/* nl() on? */
+#define RAWFLAG		SP->_raw		/* raw() on? */
+#define CURRENT_ATTR	SP->_current_attr	/* current phys attribute */
+#define CURRENT_ROW	SP->_cursrow		/* phys cursor row */
+#define CURRENT_COLUMN	SP->_curscol		/* phys cursor column */
+#define REAL_ATTR	SP->_current_attr	/* phys current attribute */
+#define WANT_CHAR(y, x)	SP->_newscr->_line[y].text[x]	/* desired state */
+#define BAUDRATE	SP->_baudrate		/* bits per second */
+
+#include <string.h>
+#include <ctype.h>
+#include <stdlib.h>
+
+#ifdef TRACE
+bool no_optimize;	/* suppress optimization */
+#endif /* TRACE */
+
+#ifdef MAIN
+#include <sys/time.h>
+
+static bool profiling = FALSE;
+static float diff;
+#endif /* MAIN */
+
+#define OPT_SIZE 512
+
+static char	*address_cursor;
+static int	carriage_return_length;
+static int	cursor_home_length;
+static int	cursor_to_ll_length;
+
+static void save_curs(void);
+static void restore_curs(void);
+
+/****************************************************************************
+ *
+ * Initialization/wrapup (including cost pre-computation)
+ *
+ ****************************************************************************/
+
+#define INFINITY	1000000	/* too high to use */
+
+static int cost(char *cap, int affcnt)
+/* compute the cost of a given operation */
+{
+    if (cap == (char *)NULL)
+	return(INFINITY);
+    else
+    {
+	char	*cp;
+	float	cum_cost = 0;	
+
+	for (cp = cap; *cp; cp++)
+	{
+	    /* extract padding, either mandatory or required */
+	    if (cp[0] == '$' && cp[1] == '<' && strchr(cp, '>'))
+	    {
+		float	number = 0;
+
+		for (cp += 2; *cp != '>'; cp++)
+		{
+		    if (isdigit(*cp))
+			number = number * 10 + (*cp - '0');
+		    else if (*cp == '.')
+			number += (*++cp - 10) / 10.0;
+		    else if (*cp == '*')
+			number *= affcnt;
+		}
+
+		cum_cost += number * 10;
+	    }
+	    else
+		cum_cost += SP->_char_padding;
+	}
+
+	return((int)cum_cost);
+    }
+}
+
+void _nc_mvcur_init(SCREEN *sp)
+/* initialize the cost structure */
+{
+    /*
+     * 9 = 7 bits + 1 parity + 1 stop.
+     */
+    if (BAUDRATE != 0)
+    	SP->_char_padding = (9 * 1000 * 10) / BAUDRATE;
+    else
+    	SP->_char_padding = 9 * 1000 * 10 / 9600; /* use some default if baudrate == 0 */
+
+    /* non-parameterized local-motion strings */
+    SP->_cr_cost = cost(carriage_return, 0);
+    SP->_home_cost = cost(cursor_home, 0);
+    SP->_ll_cost = cost(cursor_to_ll, 0);
+#ifdef TABS_OK
+    SP->_ht_cost = cost(tab, 0);
+    SP->_cbt_cost = cost(back_tab, 0);
+#endif /* TABS_OK */
+    SP->_cub1_cost = cost(cursor_left, 0);
+    SP->_cuf1_cost = cost(cursor_right, 0);
+    SP->_cud1_cost = cost(cursor_down, 0);
+    SP->_cuu1_cost = cost(cursor_up, 0);
+
+    /*
+     * Assumption: if the terminal has memory_relative addressing, the
+     * initialization strings or smcup will set single-page mode so we
+     * can treat it like absolute screen addressing.  This seems to be true
+     * for all cursor_mem_address terminal types in the terminfo database.
+     */
+    address_cursor = cursor_address ? cursor_address : cursor_mem_address;
+
+    /*
+     * Parametrized local-motion strings.  This static cost computation
+     * depends on the following assumptions:
+     *
+     * (1) They never have * padding.  In the entire master terminfo database
+     *     as of March 1995, only the obsolete Zenith Z-100 pc violates this.
+     *	   (Proportional padding is found mainly in insert, delete and scroll
+     *     capabilities).
+     *
+     * (2) The average case of cup has two two-digit parameters.  Strictly,
+     *     the average case for a 24 * 80 screen has ((10*10*(1 + 1)) +
+     *     (14*10*(1 + 2)) + (10*70*(2 + 1)) + (14*70*4)) / (24*80) = 3.458
+     *     digits of parameters.  On a 25x80 screen the average is 3.6197.
+     *     On larger screens the value gets much closer to 4.
+     *
+     * (3) The average case of cub/cuf/hpa has 2 digits of parameters
+     *     (strictly, (((10 * 1) + (70 * 2)) / 80) = 1.8750).
+     *
+     * (4) The average case of cud/cuu/vpa has 2 digits of parameters
+     *     (strictly, (((10 * 1) + (14 * 2)) / 24) = 1.5833).
+     *
+     * All these averages depend on the assumption that all parameter values
+     * are equally probable.
+     */
+    SP->_cup_cost = cost(tparm(address_cursor, 23, 23), 1);
+    SP->_cub_cost = cost(tparm(parm_left_cursor, 23), 1);
+    SP->_cuf_cost = cost(tparm(parm_right_cursor, 23), 1);
+    SP->_cud_cost = cost(tparm(parm_down_cursor, 23), 1);
+    SP->_cuu_cost = cost(tparm(parm_up_cursor, 23), 1);
+    SP->_hpa_cost = cost(tparm(column_address, 23), 1);
+    SP->_vpa_cost = cost(tparm(row_address, 23), 1);
+
+    /* initialize screen for cursor access */
+    if (enter_ca_mode)
+    {
+	TPUTS_TRACE("enter_ca_mode");
+	putp(enter_ca_mode);
+    }
+
+    /* pre-compute some capability lengths */
+    carriage_return_length = carriage_return ? strlen(carriage_return) : 0;
+    cursor_home_length     = cursor_home     ? strlen(cursor_home)     : 0;
+    cursor_to_ll_length    = cursor_to_ll    ? strlen(cursor_to_ll)    : 0;
+}
+
+void _nc_mvcur_wrap(void)
+/* wrap up cursor-addressing mode */
+{
+    /* change_scroll_region may trash the cursor location */
+    save_curs();
+    if (change_scroll_region)
+    {
+	TPUTS_TRACE("change_scroll_region");
+	putp(tparm(change_scroll_region, 0, screen_lines - 1));
+    }
+    restore_curs();
+
+    if (exit_ca_mode)
+    {
+	TPUTS_TRACE("exit_ca_mode");
+	putp(exit_ca_mode);
+    }
+}
+
+/****************************************************************************
+ *
+ * Optimized cursor movement
+ *
+ ****************************************************************************/
+
+/*
+ * Perform repeated-append, returning cost
+ */
+static __inline int
+repeated_append (int total, int num, int repeat, char *dst, char *src)
+{
+	register size_t src_len = strlen(src);
+	register size_t dst_len = 0;
+
+	if (dst)
+	    dst_len = strlen(dst);
+	if ((dst_len + repeat * src_len) < OPT_SIZE-1) {
+		total += (num * repeat);
+		if (dst) {
+		    dst += dst_len;
+		    while (repeat-- > 0) {
+			(void) strcpy(dst, src);
+			dst += src_len;
+		    }
+		}
+	} else {
+		total = INFINITY;
+	}
+	return total;
+}
+
+#ifndef NO_OPTIMIZE
+#define NEXTTAB(fr)	(fr + init_tabs - (fr % init_tabs))
+#define LASTTAB(fr)	(fr - init_tabs + (fr % init_tabs))
+
+/* Note: we'd like to inline this for speed, but GNU C barfs on the attempt. */
+
+static int
+relative_move(char *result, int from_y,int from_x,int to_y,int to_x, bool ovw)
+/* move via local motions (cuu/cuu1/cud/cud1/cub1/cub/cuf1/cuf/vpa/hpa) */
+{
+    int		n, vcost = 0, hcost = 0;
+    bool	used_lf = FALSE;
+
+    if (result)
+	result[0] = '\0';
+
+    if (to_y != from_y)
+    {
+	vcost = INFINITY;
+
+	if (row_address)
+	{
+	    if (result)
+		(void) strcpy(result, tparm(row_address, to_y));
+	    vcost = SP->_vpa_cost;
+	}
+
+	if (to_y > from_y)
+	{
+	    n = (to_y - from_y);
+
+	    if (parm_down_cursor && SP->_cud_cost < vcost)
+	    {
+		if (result)
+		    (void) strcpy(result, tparm(parm_down_cursor, n));
+		vcost = SP->_cud_cost;
+	    }
+
+	    if (cursor_down && (n * SP->_cud1_cost < vcost))
+	    {
+		if (result)
+		    result[0] = '\0';
+		if (cursor_down[0] == '\n')
+		    used_lf = TRUE;
+		vcost = repeated_append(vcost, SP->_cud1_cost, n, result, cursor_down);
+	    }
+	}
+	else /* (to_y < from_y) */
+	{
+	    n = (from_y - to_y);
+
+	    if (parm_up_cursor && SP->_cup_cost < vcost)
+	    {
+		if (result)
+		    (void) strcpy(result, tparm(parm_up_cursor, n));
+		vcost = SP->_cup_cost;
+	    }
+
+	    if (cursor_up && (n * SP->_cuu1_cost < vcost))
+	    {
+		if (result)
+		    result[0] = '\0';
+		vcost = repeated_append(vcost, SP->_cuu1_cost, n, result, cursor_up);
+	    }
+	}
+
+	if (vcost == INFINITY)
+	    return(INFINITY);
+    }
+
+    /*
+     * It may be that we're using a cud1 capability of \n with the
+     * side-effect of taking the cursor to column 0.  Deal with this.
+     */
+    if (used_lf && NLMAPPING && !RAWFLAG)
+	from_x = 0;
+
+    if (result)
+	result += strlen(result);
+
+    if (to_x != from_x)
+    {
+	char	try[OPT_SIZE];
+
+	hcost = INFINITY;
+
+	if (column_address)
+	{
+	    if (result)
+		(void) strcpy(result, tparm(column_address, to_x));
+	    hcost = SP->_hpa_cost;
+	}
+
+	if (to_x > from_x)
+	{
+	    n = to_x - from_x;
+
+	    if (parm_right_cursor && SP->_cuf_cost < hcost)
+	    {
+		if (result)
+		    (void) strcpy(result, tparm(parm_right_cursor, n));
+		hcost = SP->_cuf_cost;
+	    }
+
+	    if (cursor_right)
+	    {
+		int	lhcost = 0;
+
+		try[0] = '\0';
+
+#ifdef TABS_OK
+		/* use hard tabs, if we have them, to do as much as possible */
+		if (init_tabs > 0 && tab)
+		{
+		    int	nxt, fr;
+
+		    for (fr = from_x; (nxt = NEXTTAB(fr)) <= to_x; fr = nxt)
+		    {
+			lhcost = repeated_append(lhcost, SP->_ht_cost, 1, try, tab);
+			if (lhcost == INFINITY)
+				break;
+		    }
+
+		    n = to_x - fr;
+		    from_x = fr;
+		}
+#endif /* TABS_OK */
+
+#if defined(REAL_ATTR) && defined(WANT_CHAR)
+		/*
+		 * If we have no attribute changes, overwrite is cheaper.
+		 * Note: must suppress this by passing in ovw = FALSE whenever
+		 * WANT_CHAR would return invalid data.  In particular, this 
+		 * is true between the time a hardware scroll has been done
+		 * and the time the structure WANT_CHAR would access has been
+		 * updated.
+		 */
+		if (ovw)
+		{
+		    int	i;
+
+		    for (i = 0; i < n; i++)
+			if ((WANT_CHAR(to_y, from_x + i) & A_ATTRIBUTES) != CURRENT_ATTR)
+			{
+			    ovw = FALSE;
+			    break;
+			}
+		}
+		if (ovw)
+		{
+		    char	*sp;
+		    int	i;
+
+		    sp = try + strlen(try);
+
+		    for (i = 0; i < n; i++)
+			*sp++ = WANT_CHAR(to_y, from_x + i);
+		    *sp = '\0';
+		    lhcost += n * SP->_char_padding;
+	        }
+		else
+#endif /* defined(REAL_ATTR) && defined(WANT_CHAR) */
+		{
+		    lhcost = repeated_append(lhcost, SP->_cuf1_cost, n, try, cursor_right);
+		}
+
+		if (lhcost < hcost)
+		{
+		    if (result)
+			(void) strcpy(result, try);
+		    hcost = lhcost;
+		}
+	    }
+	}
+	else /* (to_x < from_x) */
+	{
+	    n = from_x - to_x;
+
+	    if (parm_left_cursor && SP->_cub_cost < hcost)
+	    {
+		if (result)
+		    (void) strcpy(result, tparm(parm_left_cursor, n));
+		hcost = SP->_cub_cost;
+	    }
+
+	    if (cursor_left)
+	    {
+		int	lhcost = 0;
+
+		try[0] = '\0';
+
+#ifdef TABS_OK
+		if (init_tabs > 0 && back_tab)
+		{
+		    int	nxt, fr;
+
+		    for (fr = from_x; (nxt = LASTTAB(fr)) >= to_x; fr = nxt)
+		    {
+			lhcost = repeated_append(lhcost, SP->_cbt_cost, 1, try, back_tab);
+			if (lhcost == INFINITY)
+				break;
+		    }
+
+		    n = to_x - fr;
+		}
+#endif /* TABS_OK */
+
+		lhcost = repeated_append(lhcost, SP->_cub1_cost, n, try, cursor_left);
+
+		if (lhcost < hcost)
+		{
+		    if (result)
+			(void) strcpy(result, try);
+		    hcost = lhcost;
+		}
+	    }
+	}
+
+	if (hcost == INFINITY)
+	    return(INFINITY);
+    }
+
+    return(vcost + hcost);
+}
+#endif /* !NO_OPTIMIZE */
+
+/*
+ * With the machinery set up above, it's conceivable that
+ * onscreen_mvcur could be modified into a recursive function that does
+ * an alpha-beta search of motion space, as though it were a chess
+ * move tree, with the weight function being boolean and the search
+ * depth equated to length of string.  However, this would jack up the
+ * computation cost a lot, especially on terminals without a cup
+ * capability constraining the search tree depth.  So we settle for
+ * the simpler method below.
+ */
+
+static __inline int
+onscreen_mvcur(int yold,int xold,int ynew,int xnew, bool ovw)
+/* onscreen move from (yold, xold) to (ynew, xnew) */
+{
+    char	use[OPT_SIZE], *sp;
+    int		tactic = 0, newcost, usecost = INFINITY;
+
+#ifdef MAIN
+    struct timeval before, after;
+
+    gettimeofday(&before, NULL);
+#endif /* MAIN */
+
+    /* tactic #0: use direct cursor addressing */
+    sp = tparm(address_cursor, ynew, xnew);
+    if (sp)
+    {
+	tactic = 0;
+	(void) strcpy(use, sp);
+	usecost = SP->_cup_cost;
+
+#ifdef TRACE
+	if (no_optimize)
+	    xold = yold = -1;
+#endif /* TRACE */
+
+	/*
+	 * We may be able to tell in advance that the full optimization
+	 * will probably not be worth its overhead.  Also, don't try to
+	 * use local movement if the current attribute is anything but
+	 * A_NORMAL...there are just too many ways this can screw up
+	 * (like, say, local-movement \n getting mapped to some obscure
+	 * character because A_ALTCHARSET is on).
+	 */
+	if (yold == -1 || xold == -1  || 
+	    REAL_ATTR != A_NORMAL || NOT_LOCAL(yold, xold, ynew, xnew))
+	{
+#ifdef MAIN
+	    if (!profiling)
+	    {
+		(void) fputs("nonlocal\n", stderr);
+		goto nonlocal;	/* always run the optimizer if profiling */
+	    }
+#else
+	    goto nonlocal;
+#endif /* MAIN */
+	}
+    }
+
+#ifndef NO_OPTIMIZE
+    /* tactic #1: use local movement */
+    if (yold != -1 && xold != -1
+		&& ((newcost=relative_move(NULL, yold, xold, ynew, xnew, ovw))!=INFINITY)
+		&& newcost < usecost)
+    {
+	tactic = 1;
+	usecost = newcost;
+    }
+
+    /* tactic #2: use carriage-return + local movement */
+    if (yold < screen_lines - 1 && xold < screen_columns - 1)
+    {
+	if (carriage_return
+		&& ((newcost=relative_move(NULL, yold,0,ynew,xnew, ovw)) != INFINITY)
+		&& SP->_cr_cost + newcost < usecost)
+	{
+	    tactic = 2;
+	    usecost = SP->_cr_cost + newcost;
+	}
+    }
+
+    /* tactic #3: use home-cursor + local movement */
+    if (cursor_home
+	&& ((newcost=relative_move(NULL, 0, 0, ynew, xnew, ovw)) != INFINITY)
+	&& SP->_home_cost + newcost < usecost)
+    {
+	tactic = 3;
+	usecost = SP->_home_cost + newcost;
+    }
+
+    /* tactic #4: use home-down + local movement */
+    if (cursor_to_ll
+    	&& ((newcost=relative_move(NULL, screen_lines-1, 0, ynew, xnew, ovw)) != INFINITY)
+	&& SP->_ll_cost + newcost < usecost)
+    {
+	tactic = 4;
+	usecost = SP->_ll_cost + newcost;
+    }
+
+    /*
+     * tactic #5: use left margin for wrap to right-hand side,
+     * unless strange wrap behavior indicated by xenl might hose us.
+     */
+    if (auto_left_margin && !eat_newline_glitch
+	&& yold > 0 && yold < screen_lines - 1 && cursor_left
+	&& ((newcost=relative_move(NULL, yold-1, screen_columns-1, ynew, xnew, ovw)) != INFINITY)
+	&& SP->_cr_cost + SP->_cub1_cost + newcost + newcost < usecost)
+    {
+	tactic = 5;
+	usecost = SP->_cr_cost + SP->_cub1_cost + newcost;
+    }
+
+    /*
+     * These cases are ordered by estimated relative frequency.
+     */
+    if (tactic)
+    {
+	if (tactic == 1)
+	    (void) relative_move(use, yold, xold, ynew, xnew, ovw);
+	else if (tactic == 2)
+	{
+	    (void) strcpy(use, carriage_return);
+	    (void) relative_move(use + carriage_return_length,
+				 yold,0,ynew,xnew, ovw);
+	}
+	else if (tactic == 3)
+	{
+	    (void) strcpy(use, cursor_home);
+	    (void) relative_move(use + cursor_home_length,
+				 0, 0, ynew, xnew, ovw);
+	}
+	else if (tactic == 4)
+	{
+	    (void) strcpy(use, cursor_to_ll);
+	    (void) relative_move(use + cursor_to_ll_length,
+				 screen_lines-1, 0, ynew, xnew, ovw);
+	}
+	else /* if (tactic == 5) */
+	{
+	    use[0] = '\0';
+	    if (xold > 0)
+		(void) strcat(use, carriage_return);
+	    (void) strcat(use, cursor_left);
+	    (void) relative_move(use + strlen(use),
+				 yold-1, screen_columns-1, ynew, xnew, ovw);
+	}
+    }
+#endif /* !NO_OPTIMIZE */
+
+#ifdef MAIN
+    gettimeofday(&after, NULL);
+    diff = after.tv_usec - before.tv_usec
+	+ (after.tv_sec - before.tv_sec) * 1000000;
+    if (!profiling)
+	(void) fprintf(stderr, "onscreen: %d msec, %f 28.8Kbps char-equivalents\n",
+		       (int)diff, diff/288);
+#endif /* MAIN */
+
+ nonlocal:
+    if (usecost != INFINITY)
+    {
+	TPUTS_TRACE("mvcur");
+	tputs(use, 1, _nc_outch);
+	return(OK);
+    }
+    else
+	return(ERR);
+}
+
+int mvcur(int yold, int xold, int ynew, int xnew)
+/* optimized cursor move from (yold, xold) to (ynew, xnew) */
+{
+    TR(TRACE_MOVE, ("mvcur(%d,%d,%d,%d) called", yold, xold, ynew, xnew));
+
+    if (yold == ynew && xold == xnew)
+	return(OK);
+
+    /*
+     * Most work here is rounding for terminal boundaries getting the
+     * column position implied by wraparound or the lack thereof and
+     * rolling up the screen to get ynew on the screen.
+     */
+
+    if (xnew >= screen_columns)
+    {
+	ynew += xnew / screen_columns;
+	xnew %= screen_columns;
+    }
+    if (xold >= screen_columns)
+    {
+	int	l;
+
+	l = (xold + 1) / screen_columns;
+	yold += l;
+	xold %= screen_columns;
+	if (!auto_right_margin)
+	{
+	    while (l > 0) {
+		if (newline)
+		{
+		    TPUTS_TRACE("newline");
+		    tputs(newline, 0, _nc_outch);
+		}
+		else
+		    putchar('\n');
+		l--;
+	    }
+	    xold = 0;
+	}
+	if (yold > screen_lines - 1)
+	{
+	    ynew -= yold - (screen_lines - 1);
+	    yold = screen_lines - 1;
+	}
+    }
+
+#ifdef CURSES_OVERRUN	/* not used, it takes us out of sync with curscr */
+    /*
+     * The destination line is offscreen. Try to scroll the screen to
+     * bring it onscreen.  Note: this is not a documented feature of the
+     * API.  It's here for compatibility with archaic curses code, a
+     * feature no one seems to have actually used in a long time.
+     */
+    if (ynew >= screen_lines)
+    {
+	if (mvcur_scrolln((ynew - (screen_lines - 1)), 0, screen_lines - 1, screen_lines - 1) == OK)
+	    ynew = screen_lines - 1;
+	else
+	    return(ERR);
+    }
+#endif /* CURSES_OVERRUN */
+
+    /* destination location is on screen now */
+    return(onscreen_mvcur(yold, xold, ynew, xnew, TRUE));
+}
+
+/****************************************************************************
+ *
+ * Cursor save_restore
+ *
+ ****************************************************************************/
+
+/* assumption: sc/rc is faster than cursor addressing */
+
+static int	oy, ox;		/* ugh, mvcur_scrolln() needs to see this */
+
+static void save_curs(void)
+{
+    if (save_cursor && restore_cursor)
+    {
+	TPUTS_TRACE("save_cursor");
+	putp(save_cursor);
+    }
+
+    oy = CURRENT_ROW;
+    ox = CURRENT_COLUMN;
+}
+
+static void restore_curs(void)
+{
+    if (save_cursor && restore_cursor)
+    {
+	TPUTS_TRACE("restore_cursor");
+	putp(restore_cursor);
+    }
+    else
+	onscreen_mvcur(-1, -1, oy, ox, FALSE);
+}
+
+/****************************************************************************
+ *
+ * Physical-scrolling support
+ *
+ ****************************************************************************/
+
+int _nc_mvcur_scrolln(int n, int top, int bot, int maxy)
+/* scroll region from top to bot by n lines */
+{
+    int i;
+
+    TR(TRACE_MOVE, ("mvcur_scrolln(%d, %d, %d, %d)", n, top, bot, maxy));
+
+    save_curs();
+
+    /*
+     * This code was adapted from Keith Bostic's hardware scrolling
+     * support for 4.4BSD curses.  I (esr) translated it to use terminfo
+     * capabilities, narrowed the call interface slightly, and cleaned
+     * up some convoluted tests.  I also added support for the memory_above
+     * memory_below, and non_dest_scroll_region capabilities.
+     *
+     * For this code to work, we must have either
+     * change_scroll_region and scroll forward/reverse commands, or
+     * insert and delete line capabilities.
+     * When the scrolling region has been set, the cursor has to
+     * be at the last line of the region to make the scroll
+     * happen.
+     *
+     * This code makes one aesthetic decision in the opposite way from
+     * BSD curses.  BSD curses preferred pairs of il/dl operations
+     * over scrolls, allegedly because il/dl looked faster.  We, on
+     * the other hand, prefer scrolls because (a) they're just as fast
+     * on modern terminals and (b) using them avoids bouncing an
+     * unchanged bottom section of the screen up and down, which is
+     * visually nasty.
+     */
+    if (n > 0)
+    {
+	/*
+	 * Do explicit clear to end of region if it's possible that the
+	 * terminal might hold on to stuff we push off the end.
+	 */
+	if (non_dest_scroll_region || (memory_below && bot == maxy))
+	{
+	    if (bot == maxy && clr_eos)
+	    {
+		mvcur(-1, -1, lines - n, 0);
+		TPUTS_TRACE("clr_eos");
+		tputs(clr_eos, n, _nc_outch);
+	    }
+	    else if (clr_eol)
+	    {
+		for (i = 0; i < n; i++)
+		{
+		    mvcur(-1, -1, lines - n + i, 0);
+		    TPUTS_TRACE("clr_eol");
+		    tputs(clr_eol, n, _nc_outch);
+		}
+	    }
+	}
+
+	if (change_scroll_region && (scroll_forward || parm_index))
+	{
+	    TPUTS_TRACE("change_scroll_region");
+	    tputs(tparm(change_scroll_region, top, bot), 0, _nc_outch);
+	    onscreen_mvcur(-1, -1, bot, 0, TRUE);
+	    if (parm_index != NULL)
+	    {
+		TPUTS_TRACE("parm_index");
+		tputs(tparm(parm_index, n, 0), n, _nc_outch);
+	    }
+	    else
+		for (i = 0; i < n; i++)
+		{
+		    TPUTS_TRACE("scroll_forward");
+		    tputs(scroll_forward, 0, _nc_outch);
+		}
+	    TPUTS_TRACE("change_scroll_region");
+	    tputs(tparm(change_scroll_region, 0, maxy), 0, _nc_outch);
+	    restore_curs();
+	    return(OK);
+	}
+
+	/* Scroll up the block. */
+	if (parm_index && top == 0)
+	{
+	    onscreen_mvcur(oy, ox, bot, 0, TRUE);
+	    TPUTS_TRACE("parm_index");
+	    tputs(tparm(parm_index, n, 0), n, _nc_outch);
+	}
+	else if (parm_delete_line)
+	{
+	    onscreen_mvcur(oy, ox, top, 0, TRUE);
+	    TPUTS_TRACE("parm_delete_line");
+	    tputs(tparm(parm_delete_line, n, 0), n, _nc_outch);
+	}
+	else if (delete_line)
+	{
+	    onscreen_mvcur(oy, ox, top, 0, TRUE);
+	    for (i = 0; i < n; i++)
+	    {
+		TPUTS_TRACE("parm_index");
+		tputs(delete_line, 0, _nc_outch);
+	    }
+	}
+	else if (scroll_forward && top == 0)
+	{
+	    onscreen_mvcur(oy, ox, bot, 0, TRUE);
+	    for (i = 0; i < n; i++)
+	    {
+		TPUTS_TRACE("scroll_forward");
+		tputs(scroll_forward, 0, _nc_outch);
+	    }
+	}
+	else
+	    return(ERR);
+
+	/* Push down the bottom region. */
+	if (parm_insert_line)
+	{
+	    onscreen_mvcur(top, 0, bot - n + 1, 0, FALSE);
+	    TPUTS_TRACE("parm_insert_line");
+	    tputs(tparm(parm_insert_line, n, 0), n, _nc_outch);
+	}
+	else if (insert_line)
+	{
+	    onscreen_mvcur(top, 0, bot - n + 1, 0, FALSE);
+	    for (i = 0; i < n; i++)
+	    {
+		TPUTS_TRACE("insert_line");
+		tputs(insert_line, 0, _nc_outch);
+	    }
+	}
+	else
+	    return(ERR);
+	restore_curs();
+    }
+    else /* (n < 0) */
+    {
+	/*
+	 * Explicitly clear if stuff pushed off top of region might 
+	 * be saved by the terminal.
+	 */
+	if (non_dest_scroll_region || (memory_above && top == 0))
+	    for (i = 0; i < n; i++)
+	    {
+		mvcur(-1, -1, i, 0);
+		TPUTS_TRACE("clr_eol");
+		tputs(clr_eol, n, _nc_outch);
+	    }
+
+	if (change_scroll_region && (scroll_reverse || parm_rindex))
+	{
+	    TPUTS_TRACE("change_scroll_region");
+	    tputs(tparm(change_scroll_region, top, bot), 0, _nc_outch);
+	    onscreen_mvcur(-1, -1, top, 0, TRUE);
+	    if (parm_rindex)
+	    {
+		TPUTS_TRACE("parm_rindex");
+		tputs(tparm(parm_rindex, -n, 0), -n, _nc_outch);
+	    }
+	    else
+		for (i = n; i < 0; i++)
+		{
+		    TPUTS_TRACE("scroll_reverse");
+		    tputs(scroll_reverse, 0, _nc_outch);
+		}
+	    TPUTS_TRACE("change_scroll_region");
+	    tputs(tparm(change_scroll_region, 0, maxy), 0, _nc_outch);
+	    restore_curs();
+	    return(OK);
+	}
+
+	/* Preserve the bottom lines. */
+	onscreen_mvcur(oy, ox, bot + n + 1, 0, TRUE);
+	if (parm_rindex && bot == maxy)
+	{
+	    TPUTS_TRACE("parm_rindex");
+	    tputs(tparm(parm_rindex, -n, 0), -n, _nc_outch);
+	}
+	else if (parm_delete_line)
+	{
+	    TPUTS_TRACE("parm_delete_line");
+	    tputs(tparm(parm_delete_line, -n, 0), -n, _nc_outch);
+	}
+	else if (delete_line)
+	    for (i = n; i < 0; i++)
+	    {
+		TPUTS_TRACE("delete_line");
+		tputs(delete_line, 0, _nc_outch);
+	    }
+	else if (scroll_reverse && bot == maxy)
+	    for (i = n; i < 0; i++)
+	    {
+		TPUTS_TRACE("scroll_reverse");
+		tputs(scroll_reverse, 0, _nc_outch);
+	    }
+	else
+	    return(ERR);
+
+	/* Scroll the block down. */
+	if (parm_insert_line)
+	{
+	    onscreen_mvcur(bot + n + 1, 0, top, 0, FALSE);
+	    TPUTS_TRACE("parm_insert_line");
+	    tputs(tparm(parm_insert_line, -n, 0), -n, _nc_outch);
+	}
+	else if (insert_line)
+	{
+	    onscreen_mvcur(bot + n + 1, 0, top, 0, FALSE);
+	    for (i = n; i < 0; i++)
+	    {
+		TPUTS_TRACE("insert_line");
+		tputs(insert_line, 0, _nc_outch);
+	    }
+	}
+	else
+	    return(ERR);
+	restore_curs();
+    }
+
+    return(OK);
+}
+
+#ifdef MAIN
+/****************************************************************************
+ *
+ * Movement optimizer test code
+ *
+ ****************************************************************************/
+
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <string.h>
+#include <stdlib.h>
+#include "tic.h"
+#include "dump_entry.h"
+
+char *_nc_progname = "mvcur";
+
+static unsigned long xmits;
+
+int tputs(const char *string, int affcnt, int (*outc)(int))
+/* stub tputs() that dumps sequences in a visible form */
+{
+    if (profiling)
+	xmits += strlen(string);
+    else
+	(void) fputs(_nc_visbuf(string), stdout);
+    return(OK);
+}
+
+int putp(const char *string)
+{
+    return(tputs(string, 1, _nc_outch));
+}
+
+int _nc_outch(int ch)
+{
+    putc(ch, stdout);
+    return OK;
+}
+
+static char	tname[BUFSIZ];
+
+static void load_term(void)
+{
+    (void) setupterm(tname, STDOUT_FILENO, NULL);
+}
+
+static int roll(int n)
+{
+    int i, j;
+
+    i = (RAND_MAX / n) * n;
+    while ((j = rand()) >= i)
+	continue;
+    return (j % n);
+}
+
+int main(int argc, char *argv[])
+{
+    (void) strcpy(tname, getenv("TERM"));
+    load_term();
+    _nc_setupscreen(lines, columns);
+    baudrate();
+
+    _nc_mvcur_init(SP);
+#if HAVE_SETVBUF || HAVE_SETBUFFER
+    /*
+     * Undo the effects of our optimization hack, otherwise our interactive
+     * prompts don't flush properly.
+     */
+#if HAVE_SETVBUF
+    (void) setvbuf(SP->_ofp, malloc(BUFSIZ), _IOLBF, BUFSIZ);
+#elif HAVE_SETBUFFER
+    (void) setbuffer(SP->_ofp, malloc(BUFSIZ), BUFSIZ);
+#endif
+#endif /* HAVE_SETVBUF || HAVE_SETBUFFER */
+
+    (void) puts("The mvcur tester.  Type ? for help");
+
+    fputs("smcup:", stdout);
+    putchar('\n');
+
+    for (;;)
+    {
+	int	fy, fx, ty, tx, n, i;
+	char	buf[BUFSIZ], capname[BUFSIZ];
+
+	(void) fputs("> ", stdout);
+	(void) fgets(buf, sizeof(buf), stdin);
+
+	if (buf[0] == '?')
+	{
+(void) puts("?                -- display this help message");
+(void) puts("fy fx ty tx      -- (4 numbers) display (fy,fx)->(ty,tx) move");
+(void) puts("s[croll] n t b m -- display scrolling sequence");
+(void) printf("r[eload]         -- reload terminal info for %s\n",
+	      getenv("TERM"));
+(void) puts("l[oad] <term>    -- load terminal info for type <term>");
+(void) puts("nl               -- assume NL -> CR/LF when computing (default)");
+(void) puts("nonl             -- don't assume NL -> CR/LF when computing");
+(void) puts("d[elete] <cap>   -- delete named capability");
+(void) puts("i[nspect]        -- display terminal capabilities");
+(void) puts("c[ost]           -- dump cursor-optimization cost table");
+(void) puts("o[optimize]      -- toggle movement optimization");
+(void) puts("t[orture] <num>  -- torture-test with <num> random moves");
+(void) puts("q[uit]           -- quit the program");
+	}
+	else if (sscanf(buf, "%d %d %d %d", &fy, &fx, &ty, &tx) == 4)
+	{
+	    struct timeval before, after;
+
+	    putchar('"');
+
+	    gettimeofday(&before, NULL);
+	    mvcur(fy, fx, ty, tx);
+	    gettimeofday(&after, NULL);
+
+	    printf("\" (%ld msec)\n",
+		after.tv_usec - before.tv_usec + (after.tv_sec - before.tv_sec) * 1000000);
+	}
+	else if (sscanf(buf, "s %d %d %d %d", &fy, &fx, &ty, &tx) == 4)
+	{
+	    struct timeval before, after;
+
+	    putchar('"');
+
+	    gettimeofday(&before, NULL);
+	    _nc_mvcur_scrolln(fy, fx, ty, tx);
+	    gettimeofday(&after, NULL);
+
+	    printf("\" (%ld msec)\n",
+		after.tv_usec - before.tv_usec + (after.tv_sec - before.tv_sec) * 1000000);
+	}
+	else if (buf[0] == 'r')
+	{
+	    (void) strcpy(tname, getenv("TERM"));
+	    load_term();
+	}
+	else if (sscanf(buf, "l %s", tname) == 1)
+	{
+	    load_term();
+	}
+	else if (strncmp(buf, "nl", 2) == 0)
+	{
+	    NLMAPPING = TRUE;
+	    (void) puts("NL -> CR/LF will be assumed.");
+	}
+	else if (strncmp(buf, "nonl", 4) == 0)
+	{
+	    NLMAPPING = FALSE;
+	    (void) puts("NL -> CR/LF will not be assumed.");
+	}
+	else if (sscanf(buf, "d %s", capname) == 1)
+	{
+	    struct name_table_entry const	*np = _nc_find_entry(capname,
+							 _nc_info_hash_table);
+
+	    if (np == NULL)
+		(void) printf("No such capability as \"%s\"\n", capname);
+	    else
+	    {
+		switch(np->nte_type)
+		{
+		case BOOLEAN:
+		    cur_term->type.Booleans[np->nte_index] = FALSE;
+		    (void) printf("Boolean capability `%s' (%d) turned off.\n",
+				  np->nte_name, np->nte_index);
+		    break;
+
+		case NUMBER:
+		    cur_term->type.Numbers[np->nte_index] = -1;
+		    (void) printf("Number capability `%s' (%d) set to -1.\n",
+				  np->nte_name, np->nte_index);
+		    break;
+
+		case STRING:
+		    cur_term->type.Strings[np->nte_index] = (char *)NULL;
+		    (void) printf("String capability `%s' (%d) deleted.\n",
+				  np->nte_name, np->nte_index);
+		    break;
+		}
+	    }
+	}
+	else if (buf[0] == 'i')
+	{
+	     dump_init((char *)NULL, F_TERMINFO, S_TERMINFO, 70, 0);
+	     dump_entry(&cur_term->type, NULL);
+	     putchar('\n');
+	}
+	else if (buf[0] == 'o')
+	{
+	     if (no_optimize)
+	     {
+		 no_optimize = FALSE;
+		 (void) puts("Optimization is now on.");
+	     }
+	     else
+	     {
+		 no_optimize = TRUE;
+		 (void) puts("Optimization is now off.");
+	     }
+	}
+	/* 
+	 * You can use the `t' test to profile and tune the movement
+	 * optimizer.  Use iteration values in three digits or more.
+	 * At above 5000 iterations the profile timing averages are stable
+	 * to within a millisecond or three.
+	 *
+	 * The `overhead' field of the report will help you pick a
+	 * COMPUTE_OVERHEAD figure appropriate for your processor and
+	 * expected line speed.  The `total estimated time' is
+	 * computation time plus a character-transmission time
+	 * estimate computed from the number of transmits and the baud
+	 * rate.
+	 *
+	 * Use this together with the `o' command to get a read on the
+	 * optimizer's effectiveness.  Compare the total estimated times
+	 * for `t' runs of the same length in both optimized and un-optimized
+	 * modes.  As long as the optimized times are less, the optimizer
+	 * is winning.
+	 */
+	else if (sscanf(buf, "t %d", &n) == 1)
+	{
+	    float cumtime = 0, perchar;
+	    int speeds[] = {2400, 9600, 14400, 19200, 28800, 38400, 0};
+
+	    srand((unsigned)(getpid() + time((time_t *)0)));
+	    profiling = TRUE;
+	    xmits = 0;
+	    for (i = 0; i < n; i++)
+	    {
+		/* 
+		 * This does a move test between two random locations,
+		 * Random moves probably short-change the optimizer,
+		 * which will work better on the short moves probably
+		 * typical of doupdate()'s usage pattern.  Still,
+		 * until we have better data...
+		 */
+#ifdef FIND_COREDUMP
+		int from_y = roll(lines);
+		int to_y = roll(lines);
+		int from_x = roll(columns);
+		int to_x = roll(columns);
+
+		printf("(%d,%d) -> (%d,%d)\n", from_y, from_x, to_y, to_x);
+		mvcur(from_y, from_x, to_y, to_x);
+#else
+		mvcur(roll(lines), roll(columns), roll(lines), roll(columns));
+#endif /* FIND_COREDUMP */
+		if (diff)
+		    cumtime += diff;
+	    }
+	    profiling = FALSE;
+
+	    /*
+	     * Average milliseconds per character optimization time.
+	     * This is the key figure to watch when tuning the optimizer.
+	     */
+	    perchar = cumtime / n;
+
+	    (void) printf("%d moves (%ld chars) in %d msec, %f msec each:\n", 
+			  n, xmits, (int)cumtime, perchar);
+
+	    for (i = 0; speeds[i]; i++)
+	    {
+		/*
+		 * Total estimated time for the moves, computation and 
+		 * transmission both. Transmission time is an estimate
+		 * assuming 9 bits/char, 8 bits + 1 stop bit.
+		 */
+		float totalest = cumtime + xmits * 9 * 1e6 / speeds[i];
+
+		/*
+		 * Per-character optimization overhead in character transmits
+		 * at the current speed.  Round this to the nearest integer
+		 * to figure COMPUTE_OVERHEAD for the speed.
+		 */
+		float overhead = speeds[i] * perchar / 1e6;
+
+		(void) printf("%6d bps: %3.2f char-xmits overhead; total estimated time %15.2f\n",
+			      speeds[i], overhead, totalest);
+	    }
+	}
+	else if (buf[0] == 'c')
+	{
+	    (void) printf("char padding: %d\n", SP->_char_padding);
+	    (void) printf("cr cost: %d\n", SP->_cr_cost);
+	    (void) printf("cup cost: %d\n", SP->_cup_cost);
+	    (void) printf("home cost: %d\n", SP->_home_cost);
+	    (void) printf("ll cost: %d\n", SP->_ll_cost);
+#ifdef TABS_OK
+	    (void) printf("ht cost: %d\n", SP->_ht_cost);
+	    (void) printf("cbt cost: %d\n", SP->_cbt_cost);
+#endif /* TABS_OK */
+	    (void) printf("cub1 cost: %d\n", SP->_cub1_cost);
+	    (void) printf("cuf1 cost: %d\n", SP->_cuf1_cost);
+	    (void) printf("cud1 cost: %d\n", SP->_cud1_cost);
+	    (void) printf("cuu1 cost: %d\n", SP->_cuu1_cost);
+	    (void) printf("cub cost: %d\n", SP->_cub_cost);
+	    (void) printf("cuf cost: %d\n", SP->_cuf_cost);
+	    (void) printf("cud cost: %d\n", SP->_cud_cost);
+	    (void) printf("cuu cost: %d\n", SP->_cuu_cost);
+	    (void) printf("hpa cost: %d\n", SP->_hpa_cost);
+	    (void) printf("vpa cost: %d\n", SP->_vpa_cost);
+	}
+	else if (buf[0] == 'x' || buf[0] == 'q')
+	    break;
+	else
+	    (void) puts("Invalid command.");
+    }
+
+    (void) fputs("rmcup:", stdout);
+    _nc_mvcur_wrap();
+    putchar('\n');
+
+    return(0);
+}
+
+#endif /* MAIN */
+
+/* lib_mvcur.c ends here */