libcons/

2002-09-09  Marcus Brinkmann  <marcus@gnu.org>

	* Makefile (SRCS): Add vcons-scrollback.c.
	* vcons-scrollback.c: New file.
	* cons.h (struct vcons): Add SCROLLING member.
	* file-changed.c: Include <assert.h>.
	(cons_S_file_changed): Be careful to take VCONS->scrolling into
	account when doing clipping and scrolling.

	* cons-switch.c: Roll back to earlier version with vcons ->
	vcons_entry adjustments.  The user is now expected to hold a
	reference to the VCONS.
	* cons.h: Fix prototype, too.

	* vcons-open.c (cons_vcons_open): Initialize VCONS->lock,
	VCONS->input and VCONS->display.

utils/
2002-09-09  Marcus Brinkmann  <marcus@gnu.org>

	* console-ncurses.c (console_switch): Keep a reference to the port
	instead refering to it by number.

7 files changed, 267 insertions, 63 deletions

diff --git a/libcons/ChangeLog b/libcons/ChangeLog
index ee8a9ec6..bae85db0 100644
--- a/libcons/ChangeLog
+++ b/libcons/ChangeLog
@@ -1,5 +1,20 @@
 2002-09-09  Marcus Brinkmann  <marcus@gnu.org>
 
+	* Makefile (SRCS): Add vcons-scrollback.c.
+	* vcons-scrollback.c: New file.
+	* cons.h (struct vcons): Add SCROLLING member.
+	* file-changed.c: Include <assert.h>.
+	(cons_S_file_changed): Be careful to take VCONS->scrolling into
+	account when doing clipping and scrolling.
+
+	* cons-switch.c: Roll back to earlier version with vcons ->
+	vcons_entry adjustments.  The user is now expected to hold a
+	reference to the VCONS.
+	* cons.h: Fix prototype, too.
+	
+	* vcons-open.c (cons_vcons_open): Initialize VCONS->lock,
+	VCONS->input and VCONS->display.
+
 	* vcons-remove.c: New file.
 	* Makefile (SRCS): Add vcons-destroy.c.
 	* cons.h: New type vcons_list_t.
diff --git a/libcons/Makefile b/libcons/Makefile
index a7fe6bf8..2a677e7d 100644
--- a/libcons/Makefile
+++ b/libcons/Makefile
@@ -22,7 +22,7 @@ libname = libcons
 SRCS= demuxer.c init-init.c init-loop.c opts-version.c extra-version.c \
       dir-changed.c file-changed.c opts-std-startup.c cons-lookup.c \
       cons-switch.c vcons-remove.c vcons-add.c vcons-open.c \
-      vcons-close.c vcons-destroy.c vcons-refresh.c
+      vcons-close.c vcons-destroy.c vcons-refresh.c vcons-scrollback.c
 LCLHDRS = priv.h mutations.h
 installhdrs = cons.h
 
diff --git a/libcons/cons-switch.c b/libcons/cons-switch.c
index d9aa64af..c39e83da 100644
--- a/libcons/cons-switch.c
+++ b/libcons/cons-switch.c
@@ -23,44 +23,47 @@
 
 #include "cons.h"
 
-/* Open the virtual console ID or the ACTIVE_ID plus DELTA one in CONS
-   and return it in R_VCONS, which will be locked.  */
+/* Open the virtual console ID or the virtual console DELTA steps away
+   from VCONS in the linked list and return it in R_VCONS, which will
+   be locked.  */
 error_t
-cons_switch (cons_t cons, int active_id, int id, int delta, vcons_t *r_vcons)
+cons_switch (vcons_t vcons, int id, int delta, vcons_t *r_vcons)
 {
   error_t err = 0;
+  cons_t cons = vcons->cons;
   vcons_list_t vcons_entry = NULL;
 
   if (!id && !delta)
     return 0;
 
   mutex_lock (&cons->lock);
-  vcons_entry = cons->vcons_list;
-  while (vcons_entry && vcons_entry->id != (id ?: active_id))
-    vcons_entry = vcons_entry->next;
-
-  if (!id && vcons_entry)
+  if (id)
+    {
+      vcons_entry = cons->vcons_list;
+      while (vcons_entry && vcons_entry->id != id)
+        vcons_entry = vcons_entry->next;
+    }
+  else if (delta > 0)
+    {
+      vcons_entry = vcons->vcons_entry;
+      while (delta-- > 0)
+        {
+          vcons_entry = vcons_entry->next;
+          if (!vcons_entry)
+            vcons_entry = cons->vcons_list;
+        }
+    }
+  else
     {
-      if (delta > 0)
-	{
-	  while (delta-- > 0)
-	    {
-	      vcons_entry = vcons_entry->next;
-	      if (!vcons_entry)
-		vcons_entry = cons->vcons_list;
-	    }
-	}
-      else
-	{
-	  assert (delta < 0);
-	  while (delta++ < 0)
-	    {
-	      vcons_entry = vcons_entry->prev;
-	      if (!vcons_entry)
-		vcons_entry = cons->vcons_last;
-	    }
-	}
+      assert (delta < 0);
+      while (delta++ < 0)
+        {
+          vcons_entry = vcons_entry->prev;
+          if (!vcons_entry)
+            vcons_entry = cons->vcons_last;
+        }
     }
+
   if (!vcons_entry)
     {
       mutex_unlock (&cons->lock);
@@ -78,6 +81,7 @@ cons_switch (cons_t cons, int active_id, int id, int delta, vcons_t *r_vcons)
       if (!err)
         vcons_entry->vcons = *r_vcons;
     }
+
   mutex_unlock (&cons->lock);
   return err;
 }
diff --git a/libcons/cons.h b/libcons/cons.h
index e7484db5..6b2fca49 100644
--- a/libcons/cons.h
+++ b/libcons/cons.h
@@ -103,6 +103,8 @@ struct vcons
       cons_change_t *buffer;
     } changes;
   } state;
+
+  uint32_t scrolling;
 };
 
 struct cons
@@ -206,10 +208,13 @@ void cons_vcons_add (cons_t cons, vcons_list_t vcons_entry);
    virtual console entry is removed.  CONS is locked.  */
 void cons_vcons_remove (cons_t cons, vcons_list_t vcons_entry);
 
-/* Open the virtual console ID or the ACTIVE_ID plus DELTA one in CONS
-   and return it in R_VCONS.  */
-error_t cons_switch (cons_t cons, int active_id, int id, int delta,
-		     vcons_t *r_vcons);
+/* Open the virtual console ID or the virtual console DELTA steps away
+   from VCONS in the linked list and return it in R_VCONS, which will
+   be locked.  */
+error_t cons_switch (vcons_t vcons, int id, int delta, vcons_t *r_vcons);
+
+/* Scroll back into the history of VCONS by DELTA lines.  */
+int cons_vcons_scrollback (vcons_t vcons, int delta);
 
 
 extern const struct argp cons_startup_argp;
diff --git a/libcons/file-changed.c b/libcons/file-changed.c
index 9d7a066b..b4372ed9 100644
--- a/libcons/file-changed.c
+++ b/libcons/file-changed.c
@@ -18,8 +18,10 @@
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA. */
 
-#include <mach.h>
 #include <errno.h>
+#include <assert.h>
+
+#include <mach.h>
 
 #include "cons.h"
 #include "fs_notify_S.h"
@@ -70,10 +72,27 @@ cons_S_file_changed (cons_notify_t notify, natural_t tickno,
 	    {
 	      if (change.what.cursor_pos)
 		{
+		  uint32_t old_row = vcons->state.cursor.row;
+		  uint32_t height = vcons->state.screen.height;
+		  uint32_t row;
+
 		  vcons->state.cursor.col = vcons->display->cursor.col;
-		  vcons->state.cursor.row = vcons->display->cursor.row;
-		  cons_vcons_set_cursor_pos (vcons, vcons->state.cursor.col,
-					     vcons->state.cursor.row);
+		  row = vcons->state.cursor.row = vcons->display->cursor.row;
+
+		  if (row + vcons->scrolling < height)
+		    {
+		      cons_vcons_set_cursor_pos (vcons,
+						 vcons->state.cursor.col,
+						 row + vcons->scrolling);
+		      if (old_row + vcons->scrolling >= height)
+			/* The cursor was invisible before.  */
+			cons_vcons_set_cursor_status (vcons,
+						      vcons->state.cursor.status);
+		    }
+		  else if (old_row + vcons->scrolling < height)
+		    /* The cursor was visible before.  */
+		    cons_vcons_set_cursor_status (vcons, CONS_CURSOR_INVISIBLE);
+
 		  cons_vcons_update (vcons);
 		}
 	      if (change.what.cursor_status)
@@ -86,8 +105,9 @@ cons_S_file_changed (cons_notify_t notify, natural_t tickno,
 	      if (change.what.screen_cur_line)
 		{
 		  uint32_t new_cur_line;
-		  
+
 		  new_cur_line = vcons->display->screen.cur_line;
+
 		  if (new_cur_line != vcons->state.screen.cur_line)
 		    {
 		      off_t size = vcons->state.screen.width
@@ -103,30 +123,57 @@ cons_S_file_changed (cons_notify_t notify, natural_t tickno,
 		      else
 			scrolling = UINT32_MAX - vcons->state.screen.cur_line
 			  + 1 + new_cur_line;
-		      if (scrolling > vcons->state.screen.height)
-			scrolling = vcons->state.screen.height;
-		      if (scrolling < vcons->state.screen.height)
-			cons_vcons_scroll (vcons, scrolling);
-		      vis_start = vcons->state.screen.width
-			* (new_cur_line % vcons->state.screen.lines);
-		      start = (((new_cur_line % vcons->state.screen.lines)
-				+ vcons->state.screen.height - scrolling)
-			       * vcons->state.screen.width) % size;
-		      end = start + scrolling * vcons->state.screen.width - 1;
-		      cons_vcons_write (vcons,
-					vcons->state.screen.matrix + start,
-					end < size
-					? end - start + 1 
-					: size - start,
-					0, vcons->state.screen.height
-					- scrolling);
-		      if (end >= size)
-			cons_vcons_write (vcons,
-					  vcons->state.screen.matrix,
-					  end - size + 1,
-					  0, (size - vis_start)
-					  / vcons->state.screen.width);
-		      cons_vcons_update (vcons);
+
+		      /* If we are scrollbacking, defer scrolling
+			 until absolutely necessary.  */
+		      if (vcons->scrolling)
+			{
+			  if (vcons->scrolling + scrolling <= vcons->state.screen.scr_lines)
+			    {
+			      vcons->scrolling += scrolling;
+			      scrolling = 0;
+			    }
+			  else
+			    {
+			      scrolling -= vcons->state.screen.scr_lines - vcons->scrolling;
+			      vcons->scrolling = vcons->state.screen.scr_lines;
+			    }
+			}
+
+		      if (scrolling)
+			{
+			  uint32_t cur_disp_line;
+
+			  if (new_cur_line >= vcons->scrolling)
+			    cur_disp_line = new_cur_line - vcons->scrolling;
+			  else
+			    cur_disp_line = (UINT32_MAX - (vcons->scrolling - new_cur_line)) + 1;
+
+			  if (scrolling > vcons->state.screen.height)
+			    scrolling = vcons->state.screen.height;
+			  if (scrolling < vcons->state.screen.height)
+			    cons_vcons_scroll (vcons, scrolling);
+			  vis_start = vcons->state.screen.width
+			    * (cur_disp_line % vcons->state.screen.lines);
+			  start = (((cur_disp_line % vcons->state.screen.lines)
+				    + vcons->state.screen.height - scrolling)
+				   * vcons->state.screen.width) % size;
+			  end = start + scrolling * vcons->state.screen.width - 1;
+			  cons_vcons_write (vcons,
+					    vcons->state.screen.matrix + start,
+					    end < size
+					    ? end - start + 1 
+					    : size - start,
+					    0, vcons->state.screen.height
+					    - scrolling);
+			  if (end >= size)
+			    cons_vcons_write (vcons,
+					      vcons->state.screen.matrix,
+					      end - size + 1,
+					      0, (size - vis_start)
+					      / vcons->state.screen.width);
+			  cons_vcons_update (vcons);
+			}
 		      vcons->state.screen.cur_line = new_cur_line;
 		    }
 		}
@@ -134,6 +181,8 @@ cons_S_file_changed (cons_notify_t notify, natural_t tickno,
 		{
 		  vcons->state.screen.scr_lines
 		    = vcons->display->screen.scr_lines;
+		  if (vcons->state.screen.scr_lines < vcons->scrolling)
+		    assert (!"Implement shrinking scrollback buffer! XXX");
 		}
 	      if (change.what.bell_audible)
 		{
@@ -158,8 +207,7 @@ cons_S_file_changed (cons_notify_t notify, natural_t tickno,
 	    {
 	      /* For clipping.  */
 	      off_t size = vcons->state.screen.width*vcons->state.screen.lines;
-	      off_t rotate = vcons->state.screen.width
-		* (vcons->state.screen.cur_line % vcons->state.screen.lines);
+	      off_t rotate;
 	      off_t vis_end = vcons->state.screen.height
 		* vcons->state.screen.width - 1;
 	      off_t end2 = -1;
@@ -167,6 +215,12 @@ cons_S_file_changed (cons_notify_t notify, natural_t tickno,
 	      off_t start = change.matrix.start;
 	      off_t end = change.matrix.end;
 
+	      if (vcons->state.screen.cur_line >= vcons->scrolling)
+		rotate = vcons->state.screen.cur_line - vcons->scrolling;
+	      else
+		rotate = (UINT32_MAX - (vcons->scrolling - vcons->state.screen.cur_line)) + 1;
+	      rotate = vcons->state.screen.width * (rotate % vcons->state.screen.lines);
+
 	      /* Rotate the buffer.  */
 	      start -= rotate;
 	      if (start < 0)
diff --git a/libcons/vcons-open.c b/libcons/vcons-open.c
index 0d826b63..8841b938 100644
--- a/libcons/vcons-open.c
+++ b/libcons/vcons-open.c
@@ -55,6 +55,10 @@ cons_vcons_open (cons_t cons, vcons_list_t vcons_entry, vcons_t *r_vcons)
   vcons->cons = cons;
   vcons->vcons_entry = vcons_entry;
   vcons->id = vcons_entry->id;
+  mutex_init (&vcons->lock);
+  vcons->input = -1;
+  vcons->display = MAP_FAILED;
+  vcons->scrolling = 0;
 
   /* Open the directory port of the virtual console.  */
   vconsp = file_name_lookup_under (cons->dirport, name,
diff --git a/libcons/vcons-scrollback.c b/libcons/vcons-scrollback.c
new file mode 100644
index 00000000..cfc94458
--- /dev/null
+++ b/libcons/vcons-scrollback.c
@@ -0,0 +1,122 @@
+/* vcons-scrollback.c - Move forward and backward in the scrollback buffer.
+   Copyright (C) 2002 Free Software Foundation, Inc.
+   Written by Marcus Brinkmann.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd 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 2, or (at
+   your option) any later version.
+
+   The GNU Hurd 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; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA. */
+
+#include <stdint.h>
+
+#include <cthreads.h>
+
+#include "cons.h"
+
+/* Scroll back into the history of VCONS by DELTA lines.  */
+int
+cons_vcons_scrollback (vcons_t vcons, int delta)
+{
+  int scrolling;
+  uint32_t new_scr;
+
+  mutex_lock (&vcons->lock);
+  if (delta > 0 || vcons->scrolling > (uint32_t) (-delta))
+    {
+      new_scr = vcons->scrolling + delta;
+      if (new_scr > vcons->state.screen.scr_lines)
+	new_scr = vcons->state.screen.scr_lines;
+    }
+  else
+    new_scr = 0;
+
+  if (new_scr == vcons->scrolling)
+    {
+      mutex_unlock (&vcons->lock);
+      return 0;
+    }
+  
+  scrolling = vcons->scrolling - new_scr;
+  {
+    uint32_t new_cur_line;
+    off_t size = vcons->state.screen.width
+      * vcons->state.screen.lines;
+    off_t vis_start;
+    off_t start;
+    off_t end;
+
+    if (vcons->state.screen.cur_line >= new_scr)
+      new_cur_line = vcons->state.screen.cur_line - new_scr;
+    else
+      new_cur_line = (UINT32_MAX - (new_scr - vcons->state.screen.cur_line)) + 1;
+
+    if (scrolling > 0 && (uint32_t) scrolling > vcons->state.screen.height)
+      scrolling = vcons->state.screen.height;
+    else if (scrolling < 0
+	     && (uint32_t) (-scrolling) > vcons->state.screen.height)
+      scrolling = -vcons->state.screen.height;
+    if ((scrolling > 0 && scrolling < vcons->state.screen.height)
+	|| (scrolling < 0
+	    && (uint32_t) (-scrolling) < vcons->state.screen.height))
+      cons_vcons_scroll (vcons, scrolling);
+
+    vis_start = vcons->state.screen.width
+      * (new_cur_line % vcons->state.screen.lines);
+    if (scrolling > 0)
+      start = (((new_cur_line % vcons->state.screen.lines)
+		+ vcons->state.screen.height - scrolling)
+	       * vcons->state.screen.width) % size;
+    else
+      start = vis_start;
+    end = start + abs (scrolling) * vcons->state.screen.width - 1;
+
+    cons_vcons_write (vcons,
+		      vcons->state.screen.matrix + start,
+		      end < size
+		      ? end - start + 1 
+		      : size - start,
+		      0, (scrolling > 0)
+		      ? vcons->state.screen.height - scrolling : 0);
+    if (end >= size)
+      cons_vcons_write (vcons,
+			vcons->state.screen.matrix,
+			end - size + 1,
+			0, (size - vis_start)
+			/ vcons->state.screen.width);
+  }
+
+  /* Set the new cursor position.  */
+  {
+    uint32_t row = vcons->state.cursor.row;
+    uint32_t height = vcons->state.screen.height;
+
+    if (row + new_scr < height)
+      {
+	cons_vcons_set_cursor_pos (vcons, vcons->state.cursor.col,
+				   row + new_scr);
+	if (row + vcons->scrolling >= height)
+	  /* The cursor was invisible before.  */
+	  cons_vcons_set_cursor_status (vcons, vcons->state.cursor.status);
+      }
+    else if (row + vcons->scrolling < height)
+      /* The cursor was visible before.  */
+      cons_vcons_set_cursor_status (vcons, CONS_CURSOR_INVISIBLE);
+  }
+
+  cons_vcons_update (vcons);
+  vcons->scrolling -= scrolling;
+  mutex_unlock (&vcons->lock);
+
+  return -scrolling;
+}