Adding upstream version 4.8.0.upstream/4.8.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1247 insertions, 0 deletions

diff --git a/layer.c b/layer.c
new file mode 100644
index 0000000..f505349
--- /dev/null
+++ b/layer.c
@@ -0,0 +1,1247 @@
+/* Copyright (c) 2008-2017
+ *      Juergen Weigert <jnweiger@immd4.informatik.uni-erlangen.de>
+ *      Michael Schroeder <mlschroe@immd4.informatik.uni-erlangen.de>
+ *      Micah Cowan <micah@cowan.name>
+ *      Sadrul Habib Chowdhury <sadrul@users.sourceforge.net>
+ *
+ * Copyright (c) 1993-2002, 2003, 2005, 2006, 2007
+ *      Juergen Weigert <jnweiger@immd4.informatik.uni-erlangen.de>
+ *      Michael Schroeder <mlschroe@immd4.informatik.uni-erlangen.de>
+ *
+ * Copyright (c) 1987 Oliver Laumann
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (see the file COPYING); if not, see
+ * https://www.gnu.org/licenses/, or contact Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
+ *
+ ****************************************************************
+ */
+
+#include <sys/types.h>
+
+#include "config.h"
+#include "screen.h"
+#include "mark.h"
+#include "extern.h"
+#include "braille.h"
+
+extern struct display *display, *displays;
+
+extern struct mline mline_blank, mline_null;
+extern struct mchar mchar_blank, mchar_null;
+
+extern struct layer *flayer;	/* sigh */
+extern struct LayFuncs WinLf;
+extern struct LayFuncs BlankLf;
+
+
+static struct mline *mloff __P((struct mline *, int));
+
+/*
+ * Layer subsystem.
+ *
+ * ...here is all the clipping code... beware!
+ *
+ * XXX: add some speedup code!
+ *
+ */
+
+static struct mline *mloff(struct mline *ml, int off)
+{
+  static struct mline mml;
+  if (ml == 0)
+    return 0;
+
+  mml.image = ml->image + off;
+  mml.attr  = ml->attr  + off;
+#ifdef FONT
+  mml.font  = ml->font  + off;
+  mml.fontx  = ml->fontx  + off;
+#endif
+
+#ifdef COLOR
+  mml.color = ml->color + off;
+# ifdef COLORS256
+  mml.colorx = ml->colorx + off;
+# endif
+#endif
+
+  return &mml;
+}
+
+#ifdef UTF8
+# define RECODE_MCHAR(mc) ((l->l_encoding == UTF8) != (D_encoding == UTF8) ? recode_mchar(mc, l->l_encoding, D_encoding) : (mc))
+# define RECODE_MLINE(ml) ((l->l_encoding == UTF8) != (D_encoding == UTF8) ? recode_mline(ml, l->l_width, l->l_encoding, D_encoding) : (ml))
+#else
+# define RECODE_MCHAR(mc) (mc)
+# define RECODE_MLINE(ml) (ml)
+#endif
+
+#define FOR_EACH_UNPAUSED_CANVAS(l, fn) for (cv = (l)->l_cvlist; cv; cv = cv->c_lnext) \
+  {	\
+    if ((l)->l_pause.d && cv->c_slorient)	\
+      continue;	\
+    fn	\
+  }
+
+void LGotoPos(struct layer *l, int x, int y)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int x2, y2;
+
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, x, x, y, y);
+
+#ifdef HAVE_BRAILLE
+  if (bd.bd_refreshing)
+    return;
+#endif
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    {
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      if (cv != D_forecv)
+        continue;
+      x2 = x + cv->c_xoff;
+      y2 = y + cv->c_yoff;
+      debug2("---LGotoPos %d %d\n", x2, y2);
+      if (x2 < cv->c_xs)
+        x2 = cv->c_xs;
+      if (y2 < cv->c_ys)
+        y2 = cv->c_ys;
+      if (x2 > cv->c_xe)
+        x2 = cv->c_xe;
+      if (y2 > cv->c_ye)
+        y2 = cv->c_ye;
+      for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+        if (x2 < vp->v_xs || x2 > vp->v_xe)
+          continue;
+        if (y2 < vp->v_ys || y2 > vp->v_ye)
+          continue;
+        GotoPos(x2, y2);
+        break;
+      }
+    }
+  );
+}
+
+void LScrollH(struct layer *l, int n, int y, int xs, int xe, int bce, struct mline *ol)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int y2, xs2, xe2;
+
+  if (n == 0)
+    return;
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, xs, xe, y, y);
+
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+      y2 = y + vp->v_yoff;
+      if (y2 < vp->v_ys || y2 > vp->v_ye)
+        continue;
+      xs2 = xs + vp->v_xoff;
+      xe2 = xe + vp->v_xoff;
+      if (xs2 < vp->v_xs)
+        xs2 = vp->v_xs;
+      if (xe2 > vp->v_xe)
+        xe2 = vp->v_xe;
+      if (xs2 > xe2)
+        continue;
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      ScrollH(y2, xs2, xe2, n, bce, ol ? mloff(ol, -vp->v_xoff) : 0);
+      if (xe2 - xs2 == xe - xs)
+        continue;
+      if (n > 0) {
+        xs2 = xe2 + 1 - n;
+        xe2 = xe + vp->v_xoff - n;
+      }
+      else {
+        xe2 = xs2 - 1 - n;
+        xs2 = xs + vp->v_xoff - n;
+      }
+
+      if (xs2 < vp->v_xs)
+        xs2 = vp->v_xs;
+      if (xe2 > vp->v_xe)
+        xe2 = vp->v_xe;
+      if (xs2 <= xe2)
+        RefreshArea(xs2, y2, xe2, y2, 1);
+    }
+  );
+}
+
+void LScrollV(struct layer *l, int n, int ys, int ye, int bce)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int ys2, ye2, xs2, xe2;
+  if (n == 0)
+    return;
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, 0, l->l_width - 1, ys, ye);
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+      xs2 = vp->v_xoff;
+      xe2 = l->l_width - 1 + vp->v_xoff;
+      ys2 = ys + vp->v_yoff;
+      ye2 = ye + vp->v_yoff;
+
+      if (xs2 < vp->v_xs)
+        xs2 = vp->v_xs;
+      if (xe2 > vp->v_xe)
+        xe2 = vp->v_xe;
+      if (ys2 < vp->v_ys)
+        ys2 = vp->v_ys;
+      if (ye2 > vp->v_ye)
+        ye2 = vp->v_ye;
+      if (ys2 > ye2 || xs2 > xe2)
+        continue;
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+#if 0
+      ScrollV(xs2, ys2, xe2, ye2, n, bce);
+#else
+      ScrollV(vp->v_xs, ys2, vp->v_xe, ye2, n, bce);
+#endif
+
+      debug2("LScrollV: %d %d", ys, ye);
+      debug2(" -> %d %d\n", ys2, ye2);
+      if (ye2 - ys2 == ye - ys)
+        continue;
+      if (n > 0) {
+        ys2 = ye2 + 1 - n;
+        ye2 = ye + vp->v_yoff - n;
+      }
+      else {
+        ye2 = ys2 - 1 - n;
+        ys2 = ys + vp->v_yoff - n;
+      }
+
+      debug2("LScrollV: - %d %d\n", ys2, ye2);
+      if (ys2 < vp->v_ys)
+        ys2 = vp->v_ys;
+      if (ye2 > vp->v_ye)
+        ye2 = vp->v_ye;
+      debug2("LScrollV: - %d %d\n", ys2, ye2);
+      if (ys2 <= ye2)
+        RefreshArea(xs2, ys2, xe2, ye2, 1);
+    }
+  );
+}
+
+void LInsChar(struct layer *l, struct mchar *c, int x, int y, struct mline *ol)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int xs2, xe2, y2, f;
+  struct mchar *c2, cc;
+  struct mline *rol;
+
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, x, l->l_width - 1, y, y);
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+      y2 = y + vp->v_yoff;
+      if (y2 < vp->v_ys || y2 > vp->v_ye)
+        continue;
+      xs2 = x + vp->v_xoff;
+      xe2 = l->l_width - 1 + vp->v_xoff;
+      c2 = c;
+      f = 0;
+      if (xs2 < vp->v_xs) {
+        xs2 = vp->v_xs;
+        c2 = &mchar_blank;
+        if (ol) {
+          int i = xs2 - vp->v_xoff - 1;
+          if (i >= 0 && i < l->l_width) {
+            copy_mline2mchar(&cc, ol, i);
+            c2 = &cc;
+          }
+        }
+       else
+        f = 1;
+      }
+
+      if (xe2 > vp->v_xe)
+        xe2 = vp->v_xe;
+      if (xs2 > xe2)
+        continue;
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      rol = RECODE_MLINE(ol);
+      InsChar(RECODE_MCHAR(c2), xs2, xe2, y2, mloff(rol, -vp->v_xoff));
+      if (f)
+        RefreshArea(xs2, y2, xs2, y2, 1);
+    }
+  );
+}
+
+
+void LPutChar(struct layer *l, struct mchar *c, int x, int y)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int x2, y2;
+
+#ifdef HAVE_BRAILLE
+  if (bd.bd_refreshing) {
+    BPutChar(l, c, x, y);
+    return;
+  }
+#endif
+
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, x,
+
+#ifdef DW_CHARS
+  x + (c->mbcs ? 1 : 0)
+#else
+  x
+#endif
+  , y, y);
+
+
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    {
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+        y2 = y + vp->v_yoff;
+        if (y2 < vp->v_ys || y2 > vp->v_ye)
+          continue;
+        x2 = x + vp->v_xoff;
+        if (x2 < vp->v_xs || x2 > vp->v_xe)
+          continue;
+        PutChar(RECODE_MCHAR(c), x2, y2);
+        break;
+      }
+    }
+  );
+}
+
+
+void LPutStr(struct layer *l, char *s, int n, struct mchar *r, int x, int y)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  char *s2;
+  int xs2, xe2, y2;
+
+  if (x + n > l->l_width)
+    n = l->l_width - x;
+
+#ifdef HAVE_BRAILLE
+  if (bd.bd_refreshing) {
+    BPutStr(l, s, n, r, x, y);
+    return;
+  }
+#endif
+
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, x, x + n - 1, y, y);
+
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+      y2 = y + vp->v_yoff;
+      if (y2 < vp->v_ys || y2 > vp->v_ye)
+        continue;
+      xs2 = x + vp->v_xoff;
+      xe2 = xs2 + n - 1;
+      if (xs2 < vp->v_xs)
+        xs2 = vp->v_xs;
+      if (xe2 > vp->v_xe)
+        xe2 = vp->v_xe;
+      if (xs2 > xe2)
+        continue;
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      GotoPos(xs2, y2);
+      SetRendition(r);
+      s2 = s + xs2 - x - vp->v_xoff;
+
+#ifdef UTF8
+      if (D_encoding == UTF8 && l->l_encoding != UTF8 && (r->font || r->fontx || l->l_encoding)) {
+        struct mchar mc;
+        mc = *r;
+        while (xs2 <= xe2) {
+          mc.image = *s2++;
+          PutChar(RECODE_MCHAR(&mc), xs2++, y2);
+        }
+        continue;
+      }
+#endif
+
+      while (xs2++ <= xe2)
+        PUTCHARLP(*s2++);
+    }
+  );
+}
+
+
+void LPutWinMsg(struct layer *l, char *s, int n, struct mchar *r, int x, int y)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int xs2, xe2, y2, len, len2;
+  struct mchar or;
+
+  if (x + n > l->l_width)
+    n = l->l_width - x;
+
+#ifdef HAVE_BRAILLE
+  if (bd.bd_refreshing) {
+    BPutStr(l, s, n, r, x, y);
+    return;
+  }
+#endif
+
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, x, x + n - 1, y, y);
+
+  len = strlen(s);
+  if (len > n)
+    len = n;
+
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+      y2 = y + vp->v_yoff;
+      if (y2 < vp->v_ys || y2 > vp->v_ye)
+        continue;
+      xs2 = x + vp->v_xoff;
+      xe2 = xs2 + n - 1;
+      if (xs2 < vp->v_xs)
+        xs2 = vp->v_xs;
+      if (xe2 > vp->v_xe)
+        xe2 = vp->v_xe;
+      if (xs2 > xe2)
+        continue;
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      GotoPos(xs2, y2);
+      SetRendition(r);
+      len2 = xe2 - (x + vp->v_xoff) + 1;
+      if (len2 > len)
+        len2 = len;
+      PutWinMsg(s, xs2 - x - vp->v_xoff, len2);
+      xs2 = x + vp->v_xoff + len2;
+      if (xs2 < vp->v_xs)
+        xs2 = vp->v_xs;
+      or = D_rend;
+      GotoPos(xs2, y2);
+      SetRendition(&or);
+      while (xs2++ <= xe2)
+        PUTCHARLP(' ');
+    }
+  );
+}
+
+
+void LClearLine(struct layer *l, int y, int xs, int xe, int bce, struct mline *ol)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int y2, xs2, xe2;
+
+  /* check for magic margin condition */
+  if (xs >= l->l_width)
+    xs = l->l_width - 1;
+  if (xe >= l->l_width)
+    xe = l->l_width - 1;
+  if (l->l_pause.d)
+      LayPauseUpdateRegion(l, xs, xe, y, y);
+
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+      xs2 = xs + vp->v_xoff;
+      xe2 = xe + vp->v_xoff;
+      y2  = y + vp->v_yoff;
+      if (y2 < vp->v_ys || y2 > vp->v_ye)
+        continue;
+      if (xs2 < vp->v_xs)
+        xs2 = vp->v_xs;
+      if (xe2 > vp->v_xe)
+        xe2 = vp->v_xe;
+      if (xs2 > xe2)
+        continue;
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      ClearLine(ol ? mloff(RECODE_MLINE(ol), -vp->v_xoff) : (struct mline *)0, y2, xs2, xe2, bce);
+    }
+  );
+}
+
+void LClearArea(struct layer *l, int xs, int ys, int xe, int ye, int bce, int uself)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int xs2, ys2, xe2, ye2;
+
+#ifdef HAVE_BRAILLE
+  if (bd.bd_refreshing)
+    return;
+#endif
+
+  /* Check for zero-height window */
+  if (ys < 0 || ye < ys)
+    return;
+
+  /* check for magic margin condition */
+  if (xs >= l->l_width)
+    xs = l->l_width - 1;
+  if (xe >= l->l_width)
+    xe = l->l_width - 1;
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, xs, xe, ys, ye);
+
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    {
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+        xs2 = xs + vp->v_xoff;
+        xe2 = xe + vp->v_xoff;
+        ys2 = ys + vp->v_yoff;
+        ye2 = ye + vp->v_yoff;
+
+        if (xs2 < vp->v_xs)
+          xs2 = vp->v_xs;
+        if (xe2 > vp->v_xe)
+          xe2 = vp->v_xe;
+        if (xs2 > vp->v_xe)
+          ys2++;
+        if (xe2 < vp->v_xs)
+          ye2--;
+        if (ys2 < vp->v_ys)
+          ys2 = vp->v_ys;
+        if (ye2 > vp->v_ye)
+          ye2 = vp->v_ye;
+        if (ys2 > ye2)
+          continue;
+#if 0
+        xcs = vp->v_xoff;
+        xce = l->l_width - 1 + vp->v_xoff;
+        if (xcs < vp->v_xs)
+          xcs = vp->v_xs;
+        if (xce > vp->v_xe)
+          xce = vp->v_xe;
+        if (xcs > xce)
+          continue;
+        if (ys2 != ys + vp->v_yoff)
+          xs2 = xcs;
+        if (ye2 != ye + vp->v_yoff)
+          xe2 = xce;
+        display = cv->c_display;
+        ClearArea(xs2, ys2, xcs, xce, xe2, ye2, bce, uself);
+#else
+
+        if (xs == 0 || ys2 != ys + vp->v_yoff)
+          xs2 = vp->v_xs;
+        if (xe == l->l_width - 1 || ye2 != ye + vp->v_yoff)
+          xe2 = vp->v_xe;
+        display = cv->c_display;
+        ClearArea(xs2, ys2, vp->v_xs, vp->v_xe, xe2, ye2, bce, uself);
+
+        if (xe == l->l_width - 1 && xe2 > vp->v_xoff + xe) {
+          int y;
+          SetRendition(&mchar_blank);
+          for (y = ys2; y <= ye2; y++) {
+            GotoPos(xe + vp->v_xoff + 1, y);
+            PUTCHARLP('|');
+          }
+        }
+#endif
+      }
+    }
+  );
+}
+
+
+void LCDisplayLine(struct layer *l, struct mline *ml, int y, int xs, int xe, int isblank)
+{
+  struct canvas *cv;
+  struct viewport *vp;
+  int xs2, xe2, y2;
+
+#ifdef HAVE_BRAILLE
+  if (bd.bd_refreshing) {
+    BCDisplayLine(l, ml, y, xs, xe, isblank);
+    return;
+  }
+#endif
+
+  if (l->l_pause.d)
+    LayPauseUpdateRegion(l, xs, xe, y, y);
+
+  FOR_EACH_UNPAUSED_CANVAS(l,
+    {
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+      for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+        xs2 = xs + vp->v_xoff;
+        xe2 = xe + vp->v_xoff;
+        y2  = y + vp->v_yoff;
+        if (y2 < vp->v_ys || y2 > vp->v_ye)
+          continue;
+        if (xs2 < vp->v_xs)
+          xs2 = vp->v_xs;
+        if (xe2 > vp->v_xe)
+          xe2 = vp->v_xe;
+        if (xs2 > xe2)
+          continue;
+        display = cv->c_display;
+        debug3("LCDisplayLine: DisplayLine %d, %d-%d", y2, xs2, xe2);
+        debug1("  mloff = %d\n", -vp->v_xoff);
+        DisplayLine(isblank ? &mline_blank : &mline_null, mloff(RECODE_MLINE(ml), -vp->v_xoff), y2, xs2, xe2);
+      }
+    }
+  );
+}
+
+
+void LCDisplayLineWrap(struct layer *l, struct mline *ml, int y, int from, int to, int isblank)
+{
+  struct mchar nc;
+  copy_mline2mchar(&nc, ml, 0);
+
+#ifdef DW_CHARS
+  if (dw_left(ml, 0, l->l_encoding)) {
+    nc.mbcs = ml->image[1];
+    from++;
+  }
+#endif
+
+  LWrapChar(l, &nc, y - 1, -1, -1, 0);
+  from++;
+  if (from <= to)
+    LCDisplayLine(l, ml, y, from, to, isblank);
+}
+
+
+void LSetRendition(struct layer *l, struct mchar *r)
+{
+  struct canvas *cv;
+
+  for (cv = l->l_cvlist; cv; cv = cv->c_lnext) {
+    display = cv->c_display;
+    if (D_blocked)
+      continue;
+    SetRendition(r);
+  }
+}
+
+
+void LWrapChar(struct layer *l, struct mchar *c, int y, int top, int bot, int ins)
+{
+  struct canvas *cv, *cvlist, *cvlnext;
+  struct viewport *vp, *evp, **vpp;
+  int yy, y2, yy2, top2, bot2;
+  int bce;
+
+  if (l->l_pause.d)
+    /* XXX: 'y'? */
+    LayPauseUpdateRegion(l, 0, l->l_width - 1, top, bot);
+
+#ifdef COLOR
+  bce = rend_getbg(c);
+#else
+  bce = 0;
+#endif
+
+  if (y != bot) {
+  /* simple case: no scrolling */
+  /* cursor after wrapping */
+    yy = y == l->l_height - 1 ? y : y + 1;
+
+    FOR_EACH_UNPAUSED_CANVAS(l,
+    {
+      y2 = 0;       /* gcc -Wall */
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+
+      /* find the viewport of the wrapped character */
+      for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+        y2 =  y + vp->v_yoff;
+        yy2 = yy + vp->v_yoff;
+        if (yy2 >= vp->v_ys && yy2 <= vp->v_ye && vp->v_xoff >= vp->v_xs && vp->v_xoff <= vp->v_xe)
+          break;
+      }
+
+      if (vp == 0)
+        continue;	/* nothing to do, character not visible */
+
+      /* find the viewport of the character at the end of the line*/
+      for (evp = cv->c_vplist; evp; evp = evp->v_next)
+        if (y2 >= evp->v_ys && y2 <= evp->v_ye && evp->v_xoff + l->l_width - 1 >= evp->v_xs && evp->v_xoff + l->l_width - 1 <= evp->v_xe)
+          break;	/* gotcha! */
+
+      if (evp == 0 || (ins && vp->v_xoff + l->l_width - 1 > vp->v_ye)) {
+        /* no wrapping possible */
+        debug("LWrap: can't wrap!\n");
+        cvlist = l->l_cvlist;
+        cvlnext = cv->c_lnext;
+        l->l_cvlist = cv;
+        cv->c_lnext = 0;
+ 
+        if (ins)
+          LInsChar(l, c, 0, yy, 0);
+        else
+          LPutChar(l, c, 0, yy);
+
+        l->l_cvlist = cvlist;
+        cv->c_lnext = cvlnext;
+      }
+      else
+        WrapChar(RECODE_MCHAR(c), vp->v_xoff + l->l_width, y2, vp->v_xoff, -1, vp->v_xoff + l->l_width - 1, -1, ins);
+    });
+  }
+  else
+  {
+  /* hard case: scroll up*/
+    FOR_EACH_UNPAUSED_CANVAS(l,
+    {
+      display = cv->c_display;
+      if (D_blocked)
+        continue;
+
+      /* search for wrap viewport */
+      for (vpp = &cv->c_vplist; (vp = *vpp); vpp = &vp->v_next) {
+        yy2 = bot + vp->v_yoff;
+        if (yy2 >= vp->v_ys && yy2 <= vp->v_ye && vp->v_xoff >= vp->v_xs && vp->v_xoff + l->l_width - 1 <= vp->v_xe)
+          break;
+      }
+
+      if (vp) {
+        /* great, can use Wrap on the vp */
+        /* temporarily remove vp from cvlist */
+        *vpp = vp->v_next;
+      }
+
+      if (cv->c_vplist) {
+        /* scroll all viewports != vp */
+        cvlist = l->l_cvlist;
+        cvlnext = cv->c_lnext;
+        l->l_cvlist = cv;
+        cv->c_lnext = 0;
+        LScrollV(l, 1, top, bot, bce);
+        if (!vp) {
+          if (ins)
+            LInsChar(l, c, 0, bot, 0);
+          else
+            LPutChar(l, c, 0, bot);
+        }
+
+        l->l_cvlist = cvlist;
+        cv->c_lnext = cvlnext;
+      }
+      if (vp) {
+        /* add vp back to cvlist */
+        *vpp = vp;
+        top2 = top + vp->v_yoff;
+        bot2 = bot + vp->v_yoff;
+        if (top2 < vp->v_ys)
+          top2 = vp->v_ys;
+        WrapChar(RECODE_MCHAR(c), vp->v_xoff + l->l_width, bot2, vp->v_xoff, top2, vp->v_xoff + l->l_width - 1, bot2, ins);
+      }
+    });
+  }
+}
+
+
+void LCursorVisibility(struct layer *l, int vis)
+{
+  struct canvas *cv;
+  for (cv = l->l_cvlist; cv; cv = cv->c_lnext) {
+    display = cv->c_display;
+    if (D_blocked)
+      continue;
+    if (cv != D_forecv)
+      continue;
+    CursorVisibility(vis);
+  }
+}
+
+
+void LSetFlow(struct layer *l, int flow)
+{
+  struct canvas *cv;
+  for (cv = l->l_cvlist; cv; cv = cv->c_lnext) {
+    display = cv->c_display;
+    if (cv != D_forecv)
+      continue;
+    SetFlow(flow);
+  }
+}
+
+
+void LKeypadMode(struct layer *l, int on)
+{
+  struct canvas *cv;
+  for (cv = l->l_cvlist; cv; cv = cv->c_lnext) {
+    display = cv->c_display;
+    if (D_blocked)
+      continue;
+    if (cv != D_forecv)
+      continue;
+    KeypadMode(on);
+  }
+}
+
+
+void LCursorkeysMode(struct layer *l, int on)
+{
+  struct canvas *cv;
+  for (cv = l->l_cvlist; cv; cv = cv->c_lnext) {
+    display = cv->c_display;
+    if (D_blocked)
+      continue;
+    if (cv != D_forecv)
+      continue;
+    CursorkeysMode(on);
+  }
+}
+
+
+void LMouseMode(struct layer *l, int on)
+{
+  struct canvas *cv;
+  for (cv = l->l_cvlist; cv; cv = cv->c_lnext) {
+    display = cv->c_display;
+    if (D_blocked)
+      continue;
+    if (cv != D_forecv)
+      continue;
+    MouseMode(on);
+  }
+}
+
+void LClearAll(struct layer *l, int uself)
+{
+  LClearArea(l, 0, 0, l->l_width - 1, l->l_height - 1, 0, uself);
+}
+
+
+void LRefreshAll(struct layer *l, int isblank)
+{
+  struct layer *oldflayer;
+  int y;
+
+  debug1("LRefreshAll isblank=%d\n", isblank);
+  oldflayer = flayer;
+  flayer = l;
+  if (!isblank)
+    LClearArea(l, 0, 0, l->l_width - 1, l->l_height - 1, 0, 0);
+  /* signal full refresh */
+  LayRedisplayLine(-1, -1, -1, 1);
+  for (y = 0; y < l->l_height; y++)
+    LayRedisplayLine(y, 0, l->l_width - 1, 1);
+  flayer = oldflayer;
+}
+
+void
+/*VARARGS2*/
+#if defined(USEVARARGS) && defined(__STDC__)
+LMsg(int err, const char *fmt, VA_DOTS)
+#else
+LMsg(err, fmt, VA_DOTS)
+int err;
+const char *fmt;
+VA_DECL
+#endif
+{
+  VA_LIST(ap)
+  char buf[MAXPATHLEN*2];
+  char *p = buf;
+  struct canvas *cv;
+
+  VA_START(ap, fmt);
+  fmt = DoNLS(fmt);
+  (void)vsnprintf(p, sizeof(buf) - 100, fmt, VA_ARGS(ap));
+  VA_END(ap);
+
+  if (err) {
+    p += strlen(p);
+    *p++ = ':';
+    *p++ = ' ';
+    strncpy(p, strerror(err), buf + sizeof(buf) - p - 1);
+    buf[sizeof(buf) - 1] = 0;
+  }
+
+  debug2("LMsg('%s') (%#x);\n", buf, (unsigned int)flayer);
+  for (display = displays; display; display = display->d_next) {
+    for (cv = D_cvlist; cv; cv = cv->c_next)
+      if (cv->c_layer == flayer)
+        break;
+
+    if (cv == 0)
+      continue;
+    MakeStatus(buf);
+  }
+}
+
+void
+LExtMouseMode(l, on)
+struct layer *l;
+int on;
+{
+  struct canvas *cv;
+  for (cv = l->l_cvlist; cv; cv = cv->c_lnext)
+    {
+      display = cv->c_display;
+      if (D_blocked)
+	continue;
+      if (cv != D_forecv)
+	continue;
+      ExtMouseMode(on);
+    }
+}
+
+
+/*******************************************************************/
+/*******************************************************************/
+
+/*
+ *  Layer creation / removal
+ */
+
+void KillLayerChain(struct layer *lay)
+{
+  struct canvas *cv, *ncv;
+  struct layer *l, *oldflayer;
+
+  oldflayer = flayer;
+  debug1("KillLayerChain %#x\n", lay);
+  for (l = lay; l; l = l->l_next) {
+    if (l->l_layfn == &WinLf || l->l_layfn == &BlankLf)
+      break;
+    debug1("- killing %#x\n", l);
+    if (oldflayer == l)
+      oldflayer = 0;
+    for (cv = l->l_cvlist; cv; cv = ncv) {
+      ncv = cv->c_lnext;
+      cv->c_layer = 0;
+      cv->c_lnext = 0;
+    }
+  }
+  flayer = lay;
+  while (flayer != l)
+    ExitOverlayPage();
+  flayer = oldflayer;
+}
+
+
+
+int InitOverlayPage(int datasize, struct LayFuncs *lf, int block)
+{
+  char *data;
+  struct layer *newlay;
+  struct canvas *cv, *cvp, **cvpp;
+  struct win *p;
+
+  ASSERT(flayer);
+
+  cv = 0;
+  if (display && D_forecv->c_layer == flayer)
+    cv = D_forecv;	/* work only on this cv! */
+
+  if ((newlay = (struct layer *)calloc(1, sizeof(struct layer))) == 0) {
+    Msg(0, "No memory for layer struct");
+      return -1;
+  }
+  debug2("Entering new layer on top of %#x: %#x\n", (unsigned int)flayer, newlay);
+  data = 0;
+  if (datasize) {
+    if ((data = calloc(1, datasize)) == 0) {
+      free((char *)newlay);
+      Msg(0, "No memory for layer data");
+      return -1;
+    }
+  }
+  p = Layer2Window(flayer);
+
+  if (p && (p->w_savelayer == flayer || (block && flayer->l_next == 0))) {
+    if (p->w_savelayer && p->w_savelayer != flayer && p->w_savelayer->l_cvlist == 0)
+      KillLayerChain(p->w_savelayer);
+    p->w_savelayer = newlay;
+  }
+
+  if (cv && flayer->l_next == 0 && !block) {
+    struct display *olddisplay = display;
+    display = cv->c_display;
+    RemoveStatus();
+    display = olddisplay;
+
+    /* new branch -> just get canvas vps */
+    for (cvpp = &flayer->l_cvlist; (cvp = *cvpp); cvpp = &cvp->c_lnext)
+      if (cvp == cv)
+        break;
+
+    ASSERT(cvp);
+    *cvpp = cv->c_lnext;
+    newlay->l_cvlist = cv;
+    cv->c_lnext = 0;
+    cv->c_layer = newlay;
+  }
+  else {
+    LAY_DISPLAYS(flayer, RemoveStatus());
+    if (block)
+      debug("layer is blocking\n");
+    if (block && flayer->l_layfn == &WinLf) {
+      debug("...and is first, so window gets blocked\n");
+      ASSERT(p->w_blocked == 0);
+      p->w_blocked++;
+      newlay->l_blocking = 1;
+    }
+
+    /* change all canvases */
+    newlay->l_cvlist = flayer->l_cvlist;
+
+    for (cvp = newlay->l_cvlist; cvp; cvp = cvp->c_lnext)
+      cvp->c_layer = newlay;
+    flayer->l_cvlist = 0;
+  }
+  newlay->l_width = flayer->l_width;
+  newlay->l_height = flayer->l_height;
+  newlay->l_encoding = 0;
+  newlay->l_layfn = lf;
+  newlay->l_data = data;
+  newlay->l_next = flayer;
+  newlay->l_bottom = flayer->l_bottom;
+  flayer = newlay;
+  LayRestore();
+  return 0;
+}
+
+
+extern struct layout *layouts;
+
+void ExitOverlayPage()
+{
+  struct layer *oldlay;
+  struct win *p;
+  int doredisplay = 0;
+  struct canvas *cv, *ocv;
+  struct layout *lay;
+
+  ASSERT(flayer);
+  debug1("Exiting layer %#x\n", (unsigned int)flayer);
+  oldlay = flayer;
+  if (oldlay->l_data) {
+    if (oldlay->l_layfn->lf_LayFree)
+      LayFree(oldlay->l_data);
+        free(oldlay->l_data);
+  }
+  p = Layer2Window(flayer);
+
+  flayer = oldlay->l_next;
+  if (flayer->l_layfn == &WinLf) {
+    if (oldlay->l_blocking) {
+      ASSERT(p->w_blocked > 0);
+      p->w_blocked--;
+      debug1("layer was blocking, -> w_blocked now %d\n", p->w_blocked);
+    }
+
+    /* don't warp dead layers: check cvlist */
+    if (p->w_blocked && p->w_savelayer && p->w_savelayer != flayer && oldlay->l_cvlist) {
+      debug("warping to top of blocking chain!\n");
+      /* warp ourself into savelayer */
+      flayer = p->w_savelayer;
+      doredisplay = 1;
+    }
+  }
+
+  if (p && p->w_savelayer == oldlay)
+    p->w_savelayer = flayer;
+#ifdef COPY_PASTE
+  if (p && oldlay == p->w_paster.pa_pastelayer)
+    p->w_paster.pa_pastelayer = 0;
+#endif
+
+  for (lay = layouts; lay; lay = lay->lay_next)
+    for (cv = lay->lay_cvlist; cv; cv = cv->c_next)
+      if (cv->c_layer == oldlay)
+        cv->c_layer = flayer;
+
+  /* add all canvases back into next layer's canvas list */
+  for (ocv = 0, cv = oldlay->l_cvlist; cv; cv = cv->c_lnext) {
+    cv->c_layer = flayer;
+    ocv = cv;
+  }
+  if (ocv) {
+    cv = flayer->l_cvlist;
+    ocv->c_lnext = 0;
+    flayer->l_cvlist = oldlay->l_cvlist;
+
+    /* redisplay only the warped cvs */
+    if (doredisplay)
+      LRefreshAll(flayer, 0);
+    ocv->c_lnext = cv;
+  }
+  oldlay->l_cvlist = 0;
+  LayerCleanupMemory(oldlay);
+  free((char *)oldlay);
+  LayRestore();
+  LaySetCursor();
+}
+
+int LayProcessMouse(struct layer *l, unsigned char ch)
+{
+  /* XXX: Make sure the layer accepts mouse events */
+  int len;
+  if (l->l_mouseevent.len >= sizeof(l->l_mouseevent.buffer))
+    return -1;
+
+  len = l->l_mouseevent.len++;
+  l->l_mouseevent.buffer[len] = (len > 0 ? ch - 33 : ch);
+  return (l->l_mouseevent.len == sizeof(l->l_mouseevent.buffer));
+}
+
+void LayProcessMouseSwitch(struct layer *l, int s)
+{
+  if ((l->l_mouseevent.start = s))
+    l->l_mouseevent.len = 0;
+}
+
+
+void LayPause(struct layer *layer, int pause)
+{
+  struct canvas *cv;
+  int line;
+  struct win *win;
+  pause = !!pause;
+
+  if (layer->l_pause.d == pause)
+    return;
+
+  if ((layer->l_pause.d = pause)) {
+    /* Start pausing */
+    layer->l_pause.top = layer->l_pause.bottom = -1;
+    return;
+  }
+
+  /* Unpause. So refresh the regions in the displays! */
+  if (layer->l_pause.top == -1 && layer->l_pause.bottom == -1)
+    return;
+
+  if (layer->l_layfn == &WinLf)  /* Currently, this will always be the case! */
+    win = layer->l_data;
+  else
+    win = NULL;
+
+  for (cv = layer->l_cvlist; cv; cv = cv->c_lnext) {
+    struct viewport *vp;
+
+    if (!cv->c_slorient)
+      continue;              /* Wasn't split, so already updated. */
+    display = cv->c_display;
+    for (vp = cv->c_vplist; vp; vp = vp->v_next) {
+      for (line = layer->l_pause.top; line <= layer->l_pause.bottom; line++) {
+        int xs, xe;
+        if (line + vp->v_yoff >= vp->v_ys && line + vp->v_yoff <= vp->v_ye &&
+             ((xs = layer->l_pause.left[line]) >= 0) &&
+             ((xe = layer->l_pause.right[line]) >= 0)) {
+           xs += vp->v_xoff;
+           xe += vp->v_xoff;
+
+          if (xs < vp->v_xs) xs = vp->v_xs;
+          if (xe > vp->v_xe) xe = vp->v_xe;
+
+#if defined(DW_CHARS) && defined(UTF8)
+          if (layer->l_encoding == UTF8 && xe < vp->v_xe && win) {
+            struct mline *ml = win->w_mlines + line;
+            if (dw_left(ml, xe, UTF8))
+              xe++;
+          }
+#endif
+
+          if (xs <= xe)
+            RefreshLine(line + vp->v_yoff, xs, xe, 0);
+        }
+      }
+    }
+
+    if (cv == D_forecv) {
+      int cx = layer->l_x + cv->c_xoff;
+      int cy = layer->l_y + cv->c_yoff;
+
+      if (cx < cv->c_xs) cx = cv->c_xs;
+      if (cy < cv->c_ys) cy = cv->c_ys;
+      if (cx > cv->c_xe) cx = cv->c_xe;
+      if (cy > cv->c_ye) cy = cv->c_ye;
+
+      GotoPos(cx, cy);
+    }
+  }
+
+  for (line = layer->l_pause.top; line <= layer->l_pause.bottom; line++)
+    layer->l_pause.left[line] = layer->l_pause.right[line] = -1;
+}
+
+void LayPauseUpdateRegion(struct layer *layer, int xs, int xe, int ys, int ye)
+{
+  if (!layer->l_pause.d)
+    return;
+  if (ys < 0)
+    ys = 0;
+  if (ye >= layer->l_height)
+    ye = layer->l_height - 1;
+  if (xe >= layer->l_width)
+    xe = layer->l_width - 1;
+
+  if (layer->l_pause.top == -1 || layer->l_pause.top > ys)
+    layer->l_pause.top = ys;
+  if (layer->l_pause.bottom < ye) {
+    layer->l_pause.bottom = ye;
+
+    if (layer->l_pause.lines <= ye) {
+      int o = layer->l_pause.lines;
+      layer->l_pause.lines = ye + 32;
+      layer->l_pause.left = realloc(layer->l_pause.left, sizeof(int) * layer->l_pause.lines);
+      layer->l_pause.right = realloc(layer->l_pause.right, sizeof(int) * layer->l_pause.lines);
+      while (o < layer->l_pause.lines) {
+        layer->l_pause.left[o] = layer->l_pause.right[o] = -1;
+        o++;
+      }
+    }
+  }
+  while (ys <= ye) {
+    if (layer->l_pause.left[ys] == -1 || layer->l_pause.left[ys] > xs)
+    layer->l_pause.left[ys] = xs;
+      if (layer->l_pause.right[ys] < xe)
+    layer->l_pause.right[ys] = xe;
+      ys++;
+  }
+}
+
+void LayerCleanupMemory(struct layer *layer)
+{
+  if (layer->l_pause.left)
+    free(layer->l_pause.left);
+  if (layer->l_pause.right)
+    free(layer->l_pause.right);
+}