1 files changed, 607 insertions, 0 deletions

diff --git a/contrib/nvi/vi/vs_split.c b/contrib/nvi/vi/vs_split.c
new file mode 100644
index 0000000..d017354
--- /dev/null
+++ b/contrib/nvi/vi/vs_split.c
@@ -0,0 +1,607 @@
+/*-
+ * Copyright (c) 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ * Copyright (c) 1993, 1994, 1995, 1996
+ *	Keith Bostic.  All rights reserved.
+ *
+ * See the LICENSE file for redistribution information.
+ */
+
+#include "config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)vs_split.c	10.31 (Berkeley) 10/13/96";
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <sys/queue.h>
+#include <sys/time.h>
+
+#include <bitstring.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "../common/common.h"
+#include "vi.h"
+
+static SCR *vs_getbg __P((SCR *, char *));
+
+/*
+ * vs_split --
+ *	Create a new screen.
+ *
+ * PUBLIC: int vs_split __P((SCR *, SCR *, int));
+ */
+int
+vs_split(sp, new, ccl)
+	SCR *sp, *new;
+	int ccl;		/* Colon-command line split. */
+{
+	GS *gp;
+	SMAP *smp;
+	size_t half;
+	int issmallscreen, splitup;
+
+	gp = sp->gp;
+
+	/* Check to see if it's possible. */
+	/* XXX: The IS_ONELINE fix will change this, too. */
+	if (sp->rows < 4) {
+		msgq(sp, M_ERR,
+		    "222|Screen must be larger than %d lines to split", 4 - 1);
+		return (1);
+	}
+
+	/* Wait for any messages in the screen. */
+	vs_resolve(sp, NULL, 1);
+
+	half = sp->rows / 2;
+	if (ccl && half > 6)
+		half = 6;
+
+	/* Get a new screen map. */
+	CALLOC(sp, _HMAP(new), SMAP *, SIZE_HMAP(sp), sizeof(SMAP));
+	if (_HMAP(new) == NULL)
+		return (1);
+	_HMAP(new)->lno = sp->lno;
+	_HMAP(new)->coff = 0;
+	_HMAP(new)->soff = 1;
+
+	/*
+	 * Small screens: see vs_refresh.c section 6a.  Set a flag so
+	 * we know to fix the screen up later.
+	 */
+	issmallscreen = IS_SMALL(sp);
+
+	/* The columns in the screen don't change. */
+	new->cols = sp->cols;
+
+	/*
+	 * Split the screen, and link the screens together.  If creating a
+	 * screen to edit the colon command line or the cursor is in the top
+	 * half of the current screen, the new screen goes under the current
+	 * screen.  Else, it goes above the current screen.
+	 *
+	 * Recalculate current cursor position based on sp->lno, we're called
+	 * with the cursor on the colon command line.  Then split the screen
+	 * in half and update the shared information.
+	 */
+	splitup =
+	    !ccl && (vs_sm_cursor(sp, &smp) ? 0 : (smp - HMAP) + 1) >= half;
+	if (splitup) {				/* Old is bottom half. */
+		new->rows = sp->rows - half;	/* New. */
+		new->woff = sp->woff;
+		sp->rows = half;		/* Old. */
+		sp->woff += new->rows;
+						/* Link in before old. */
+		CIRCLEQ_INSERT_BEFORE(&gp->dq, sp, new, q);
+
+		/*
+		 * If the parent is the bottom half of the screen, shift
+		 * the map down to match on-screen text.
+		 */
+		memmove(_HMAP(sp), _HMAP(sp) + new->rows,
+		    (sp->t_maxrows - new->rows) * sizeof(SMAP));
+	} else {				/* Old is top half. */
+		new->rows = half;		/* New. */
+		sp->rows -= half;		/* Old. */
+		new->woff = sp->woff + sp->rows;
+						/* Link in after old. */
+		CIRCLEQ_INSERT_AFTER(&gp->dq, sp, new, q);
+	}
+
+	/* Adjust maximum text count. */
+	sp->t_maxrows = IS_ONELINE(sp) ? 1 : sp->rows - 1;
+	new->t_maxrows = IS_ONELINE(new) ? 1 : new->rows - 1;
+
+	/*
+	 * Small screens: see vs_refresh.c, section 6a.
+	 *
+	 * The child may have different screen options sizes than the parent,
+	 * so use them.  Guarantee that text counts aren't larger than the
+	 * new screen sizes.
+	 */
+	if (issmallscreen) {
+		/* Fix the text line count for the parent. */
+		if (splitup)
+			sp->t_rows -= new->rows;
+
+		/* Fix the parent screen. */
+		if (sp->t_rows > sp->t_maxrows)
+			sp->t_rows = sp->t_maxrows;
+		if (sp->t_minrows > sp->t_maxrows)
+			sp->t_minrows = sp->t_maxrows;
+
+		/* Fix the child screen. */
+		new->t_minrows = new->t_rows = O_VAL(sp, O_WINDOW);
+		if (new->t_rows > new->t_maxrows)
+			new->t_rows = new->t_maxrows;
+		if (new->t_minrows > new->t_maxrows)
+			new->t_minrows = new->t_maxrows;
+	} else {
+		sp->t_minrows = sp->t_rows = IS_ONELINE(sp) ? 1 : sp->rows - 1;
+
+		/*
+		 * The new screen may be a small screen, even if the parent
+		 * was not.  Don't complain if O_WINDOW is too large, we're
+		 * splitting the screen so the screen is much smaller than
+		 * normal.
+		 */
+		new->t_minrows = new->t_rows = O_VAL(sp, O_WINDOW);
+		if (new->t_rows > new->rows - 1)
+			new->t_minrows = new->t_rows =
+			    IS_ONELINE(new) ? 1 : new->rows - 1;
+	}
+
+	/* Adjust the ends of the new and old maps. */
+	_TMAP(sp) = IS_ONELINE(sp) ?
+	    _HMAP(sp) : _HMAP(sp) + (sp->t_rows - 1);
+	_TMAP(new) = IS_ONELINE(new) ?
+	    _HMAP(new) : _HMAP(new) + (new->t_rows - 1);
+
+	/* Reset the length of the default scroll. */
+	if ((sp->defscroll = sp->t_maxrows / 2) == 0)
+		sp->defscroll = 1;
+	if ((new->defscroll = new->t_maxrows / 2) == 0)
+		new->defscroll = 1;
+
+	/*
+	 * Initialize the screen flags:
+	 *
+	 * If we're in vi mode in one screen, we don't have to reinitialize.
+	 * This isn't just a cosmetic fix.  The path goes like this:
+	 *
+	 *	return into vi(), SC_SSWITCH set
+	 *	call vs_refresh() with SC_STATUS set
+	 *	call vs_resolve to display the status message
+	 *	call vs_refresh() because the SC_SCR_VI bit isn't set
+	 *
+	 * Things go downhill at this point.
+	 *
+	 * Draw the new screen from scratch, and add a status line.
+	 */
+	F_SET(new,
+	    SC_SCR_REFORMAT | SC_STATUS |
+	    F_ISSET(sp, SC_EX | SC_VI | SC_SCR_VI | SC_SCR_EX));
+	return (0);
+}
+
+/*
+ * vs_discard --
+ *	Discard the screen, folding the real-estate into a related screen,
+ *	if one exists, and return that screen.
+ *
+ * PUBLIC: int vs_discard __P((SCR *, SCR **));
+ */
+int
+vs_discard(sp, spp)
+	SCR *sp, **spp;
+{
+	SCR *nsp;
+	dir_t dir;
+
+	/*
+	 * Save the old screen's cursor information.
+	 *
+	 * XXX
+	 * If called after file_end(), and the underlying file was a tmp
+	 * file, it may have gone away.
+	 */
+	if (sp->frp != NULL) {
+		sp->frp->lno = sp->lno;
+		sp->frp->cno = sp->cno;
+		F_SET(sp->frp, FR_CURSORSET);
+	}
+
+	/*
+	 * Add into a previous screen and then into a subsequent screen, as
+	 * they're the closest to the current screen.  If that doesn't work,
+	 * there was no screen to join.
+	 */
+	if ((nsp = sp->q.cqe_prev) != (void *)&sp->gp->dq) {
+		nsp->rows += sp->rows;
+		sp = nsp;
+		dir = FORWARD;
+	} else if ((nsp = sp->q.cqe_next) != (void *)&sp->gp->dq) {
+		nsp->woff = sp->woff;
+		nsp->rows += sp->rows;
+		sp = nsp;
+		dir = BACKWARD;
+	} else
+		sp = NULL;
+
+	if (spp != NULL)
+		*spp = sp;
+	if (sp == NULL)
+		return (0);
+		
+	/*
+	 * Make no effort to clean up the discarded screen's information.  If
+	 * it's not exiting, we'll do the work when the user redisplays it.
+	 *
+	 * Small screens: see vs_refresh.c section 6a.  Adjust text line info,
+	 * unless it's a small screen.
+	 *
+	 * Reset the length of the default scroll.
+	 */
+	if (!IS_SMALL(sp))
+		sp->t_rows = sp->t_minrows = sp->rows - 1;
+	sp->t_maxrows = sp->rows - 1;
+	sp->defscroll = sp->t_maxrows / 2;
+	*(HMAP + (sp->t_rows - 1)) = *TMAP;
+	TMAP = HMAP + (sp->t_rows - 1);
+
+	/*
+	 * Draw the new screen from scratch, and add a status line.
+	 *
+	 * XXX
+	 * We could play games with the map, if this were ever to be a
+	 * performance problem, but I wrote the code a few times and it
+	 * was never clean or easy.
+	 */
+	switch (dir) {
+	case FORWARD:
+		vs_sm_fill(sp, OOBLNO, P_TOP);
+		break;
+	case BACKWARD:
+		vs_sm_fill(sp, OOBLNO, P_BOTTOM);
+		break;
+	default:
+		abort();
+	}
+
+	F_SET(sp, SC_STATUS);
+	return (0);
+}
+
+/*
+ * vs_fg --
+ *	Background the current screen, and foreground a new one.
+ *
+ * PUBLIC: int vs_fg __P((SCR *, SCR **, CHAR_T *, int));
+ */
+int
+vs_fg(sp, nspp, name, newscreen)
+	SCR *sp, **nspp;
+	CHAR_T *name;
+	int newscreen;
+{
+	GS *gp;
+	SCR *nsp;
+
+	gp = sp->gp;
+
+	if (newscreen)
+		/* Get the specified background screen. */
+		nsp = vs_getbg(sp, name);
+	else
+		/* Swap screens. */
+		if (vs_swap(sp, &nsp, name))
+			return (1);
+
+	if ((*nspp = nsp) == NULL) {
+		msgq_str(sp, M_ERR, name,
+		    name == NULL ?
+		    "223|There are no background screens" :
+		    "224|There's no background screen editing a file named %s");
+		return (1);
+	}
+
+	if (newscreen) {
+		/* Remove the new screen from the background queue. */
+		CIRCLEQ_REMOVE(&gp->hq, nsp, q);
+
+		/* Split the screen; if we fail, hook the screen back in. */
+		if (vs_split(sp, nsp, 0)) {
+			CIRCLEQ_INSERT_TAIL(&gp->hq, nsp, q);
+			return (1);
+		}
+	} else {
+		/* Move the old screen to the background queue. */
+		CIRCLEQ_REMOVE(&gp->dq, sp, q);
+		CIRCLEQ_INSERT_TAIL(&gp->hq, sp, q);
+	}
+	return (0);
+}
+
+/*
+ * vs_bg --
+ *	Background the screen, and switch to the next one.
+ *
+ * PUBLIC: int vs_bg __P((SCR *));
+ */
+int
+vs_bg(sp)
+	SCR *sp;
+{
+	GS *gp;
+	SCR *nsp;
+
+	gp = sp->gp;
+
+	/* Try and join with another screen. */
+	if (vs_discard(sp, &nsp))
+		return (1);
+	if (nsp == NULL) {
+		msgq(sp, M_ERR,
+		    "225|You may not background your only displayed screen");
+		return (1);
+	}
+
+	/* Move the old screen to the background queue. */
+	CIRCLEQ_REMOVE(&gp->dq, sp, q);
+	CIRCLEQ_INSERT_TAIL(&gp->hq, sp, q);
+
+	/* Toss the screen map. */
+	free(_HMAP(sp));
+	_HMAP(sp) = NULL;
+
+	/* Switch screens. */
+	sp->nextdisp = nsp;
+	F_SET(sp, SC_SSWITCH);
+
+	return (0);
+}
+
+/*
+ * vs_swap --
+ *	Swap the current screen with a backgrounded one.
+ *
+ * PUBLIC: int vs_swap __P((SCR *, SCR **, char *));
+ */
+int
+vs_swap(sp, nspp, name)
+	SCR *sp, **nspp;
+	char *name;
+{
+	GS *gp;
+	SCR *nsp;
+
+	gp = sp->gp;
+
+	/* Get the specified background screen. */
+	if ((*nspp = nsp = vs_getbg(sp, name)) == NULL)
+		return (0);
+
+	/*
+	 * Save the old screen's cursor information.
+	 *
+	 * XXX
+	 * If called after file_end(), and the underlying file was a tmp
+	 * file, it may have gone away.
+	 */
+	if (sp->frp != NULL) {
+		sp->frp->lno = sp->lno;
+		sp->frp->cno = sp->cno;
+		F_SET(sp->frp, FR_CURSORSET);
+	}
+
+	/* Switch screens. */
+	sp->nextdisp = nsp;
+	F_SET(sp, SC_SSWITCH);
+
+	/* Initialize terminal information. */
+	VIP(nsp)->srows = VIP(sp)->srows;
+
+	/* Initialize screen information. */
+	nsp->cols = sp->cols;
+	nsp->rows = sp->rows;	/* XXX: Only place in vi that sets rows. */
+	nsp->woff = sp->woff;
+
+	/*
+	 * Small screens: see vs_refresh.c, section 6a.
+	 *
+	 * The new screens may have different screen options sizes than the
+	 * old one, so use them.  Make sure that text counts aren't larger
+	 * than the new screen sizes.
+	 */
+	if (IS_SMALL(nsp)) {
+		nsp->t_minrows = nsp->t_rows = O_VAL(nsp, O_WINDOW);
+		if (nsp->t_rows > sp->t_maxrows)
+			nsp->t_rows = nsp->t_maxrows;
+		if (nsp->t_minrows > sp->t_maxrows)
+			nsp->t_minrows = nsp->t_maxrows;
+	} else
+		nsp->t_rows = nsp->t_maxrows = nsp->t_minrows = nsp->rows - 1;
+
+	/* Reset the length of the default scroll. */
+	nsp->defscroll = nsp->t_maxrows / 2;
+
+	/* Allocate a new screen map. */
+	CALLOC_RET(nsp, _HMAP(nsp), SMAP *, SIZE_HMAP(nsp), sizeof(SMAP));
+	_TMAP(nsp) = _HMAP(nsp) + (nsp->t_rows - 1);
+
+	/* Fill the map. */
+	if (vs_sm_fill(nsp, nsp->lno, P_FILL))
+		return (1);
+
+	/*
+	 * The new screen replaces the old screen in the parent/child list.
+	 * We insert the new screen after the old one.  If we're exiting,
+	 * the exit will delete the old one, if we're foregrounding, the fg
+	 * code will move the old one to the background queue.
+	 */
+	CIRCLEQ_REMOVE(&gp->hq, nsp, q);
+	CIRCLEQ_INSERT_AFTER(&gp->dq, sp, nsp, q);
+
+	/*
+	 * Don't change the screen's cursor information other than to
+	 * note that the cursor is wrong.
+	 */
+	F_SET(VIP(nsp), VIP_CUR_INVALID);
+
+	/* Draw the new screen from scratch, and add a status line. */
+	F_SET(nsp, SC_SCR_REDRAW | SC_STATUS);
+	return (0);
+}
+
+/*
+ * vs_resize --
+ *	Change the absolute size of the current screen.
+ *
+ * PUBLIC: int vs_resize __P((SCR *, long, adj_t));
+ */
+int
+vs_resize(sp, count, adj)
+	SCR *sp;
+	long count;
+	adj_t adj;
+{
+	GS *gp;
+	SCR *g, *s;
+	size_t g_off, s_off;
+
+	gp = sp->gp;
+
+	/*
+	 * Figure out which screens will grow, which will shrink, and
+	 * make sure it's possible.
+	 */
+	if (count == 0)
+		return (0);
+	if (adj == A_SET) {
+		if (sp->t_maxrows == count)
+			return (0);
+		if (sp->t_maxrows > count) {
+			adj = A_DECREASE;
+			count = sp->t_maxrows - count;
+		} else {
+			adj = A_INCREASE;
+			count = count - sp->t_maxrows;
+		}
+	}
+
+	g_off = s_off = 0;
+	if (adj == A_DECREASE) {
+		if (count < 0)
+			count = -count;
+		s = sp;
+		if (s->t_maxrows < MINIMUM_SCREEN_ROWS + count)
+			goto toosmall;
+		if ((g = sp->q.cqe_prev) == (void *)&gp->dq) {
+			if ((g = sp->q.cqe_next) == (void *)&gp->dq)
+				goto toobig;
+			g_off = -count;
+		} else
+			s_off = count;
+	} else {
+		g = sp;
+		if ((s = sp->q.cqe_next) != (void *)&gp->dq)
+			if (s->t_maxrows < MINIMUM_SCREEN_ROWS + count)
+				s = NULL;
+			else
+				s_off = count;
+		else
+			s = NULL;
+		if (s == NULL) {
+			if ((s = sp->q.cqe_prev) == (void *)&gp->dq) {
+toobig:				msgq(sp, M_BERR, adj == A_DECREASE ?
+				    "227|The screen cannot shrink" :
+				    "228|The screen cannot grow");
+				return (1);
+			}
+			if (s->t_maxrows < MINIMUM_SCREEN_ROWS + count) {
+toosmall:			msgq(sp, M_BERR,
+				    "226|The screen can only shrink to %d rows",
+				    MINIMUM_SCREEN_ROWS);
+				return (1);
+			}
+			g_off = -count;
+		}
+	}
+
+	/*
+	 * Fix up the screens; we could optimize the reformatting of the
+	 * screen, but this isn't likely to be a common enough operation
+	 * to make it worthwhile.
+	 */
+	s->rows += -count;
+	s->woff += s_off;
+	g->rows += count;
+	g->woff += g_off;
+
+	g->t_rows += count;
+	if (g->t_minrows == g->t_maxrows)
+		g->t_minrows += count;
+	g->t_maxrows += count;
+	_TMAP(g) += count;
+	F_SET(g, SC_SCR_REFORMAT | SC_STATUS);
+
+	s->t_rows -= count;
+	s->t_maxrows -= count;
+	if (s->t_minrows > s->t_maxrows)
+		s->t_minrows = s->t_maxrows;
+	_TMAP(s) -= count;
+	F_SET(s, SC_SCR_REFORMAT | SC_STATUS);
+
+	return (0);
+}
+
+/*
+ * vs_getbg --
+ *	Get the specified background screen, or, if name is NULL, the first
+ *	background screen.
+ */
+static SCR *
+vs_getbg(sp, name)
+	SCR *sp;
+	char *name;
+{
+	GS *gp;
+	SCR *nsp;
+	char *p;
+
+	gp = sp->gp;
+
+	/* If name is NULL, return the first background screen on the list. */
+	if (name == NULL) {
+		nsp = gp->hq.cqh_first;
+		return (nsp == (void *)&gp->hq ? NULL : nsp);
+	}
+
+	/* Search for a full match. */
+	for (nsp = gp->hq.cqh_first;
+	    nsp != (void *)&gp->hq; nsp = nsp->q.cqe_next)
+		if (!strcmp(nsp->frp->name, name))
+			break;
+	if (nsp != (void *)&gp->hq)
+		return (nsp);
+
+	/* Search for a last-component match. */
+	for (nsp = gp->hq.cqh_first;
+	    nsp != (void *)&gp->hq; nsp = nsp->q.cqe_next) {
+		if ((p = strrchr(nsp->frp->name, '/')) == NULL)
+			p = nsp->frp->name;
+		else
+			++p;
+		if (!strcmp(p, name))
+			break;
+	}
+	if (nsp != (void *)&gp->hq)
+		return (nsp);
+
+	return (NULL);
+}