2002-09-14 Marcus Brinkmann <marcus@gnu.org>

	* Makefile (SRCS): Add vcons-input.c.
	* vcons-input.c: New file.

	* vcons-scrollback.c (_cons_vcons_scrollback): New function.
	(cons_vcons_scrollback): Reimplement in terms of
	_cons_vcons_scrollback.
	* cons.h (cons_scroll_t): New type.
	(cons_vcons_scrollback): Update prototype.

	* priv.h (_cons_jump_down_at_input): New extern.
	(_cons_jump_down_at_output): Likewise.
	(_cons_vcons_scrollback): New prototype.
	* opts-std-startup.c (OPT_JUMP_DOWN_AT_INPUT): New macro.
	(OPT_JUMP_DOWN_AT_OUTPUT): Likewise.
	(_cons_jump_down_at_input): New variable.
	(_cons_jump_down_at_output): Likewise.
	(startup_options): Add new options --jump-down-at-input and
	--jump-down-at-output.
	(parse_startup_opt): Handle these new options.
	* file-changed.c (cons_S_file_changed): Support the jump down at
	output option.

8 files changed, 204 insertions, 28 deletions

diff --git a/libcons/ChangeLog b/libcons/ChangeLog
index 6b21a264..a6e5c3c3 100644
--- a/libcons/ChangeLog
+++ b/libcons/ChangeLog
@@ -1,3 +1,27 @@
+2002-09-14  Marcus Brinkmann  <marcus@gnu.org>
+
+	* Makefile (SRCS): Add vcons-input.c.
+	* vcons-input.c: New file.
+
+	* vcons-scrollback.c (_cons_vcons_scrollback): New function.
+	(cons_vcons_scrollback): Reimplement in terms of
+	_cons_vcons_scrollback.
+	* cons.h (cons_scroll_t): New type.
+	(cons_vcons_scrollback): Update prototype.
+
+	* priv.h (_cons_jump_down_at_input): New extern.
+	(_cons_jump_down_at_output): Likewise.
+	(_cons_vcons_scrollback): New prototype.
+	* opts-std-startup.c (OPT_JUMP_DOWN_AT_INPUT): New macro.
+	(OPT_JUMP_DOWN_AT_OUTPUT): Likewise.
+	(_cons_jump_down_at_input): New variable.
+	(_cons_jump_down_at_output): Likewise.
+	(startup_options): Add new options --jump-down-at-input and
+	--jump-down-at-output.
+	(parse_startup_opt): Handle these new options.
+	* file-changed.c (cons_S_file_changed): Support the jump down at
+	output option.
+
 2002-09-10  Marcus Brinkmann  <marcus@gnu.org>
 
 	* file-changed.c (cons_S_file_changed): Fix typo in last change.
diff --git a/libcons/Makefile b/libcons/Makefile
index 2a677e7d..576f8b66 100644
--- a/libcons/Makefile
+++ b/libcons/Makefile
@@ -22,7 +22,8 @@ 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-scrollback.c
+      vcons-close.c vcons-destroy.c vcons-refresh.c vcons-scrollback.c \
+      vcons-input.c
 LCLHDRS = priv.h mutations.h
 installhdrs = cons.h
 
diff --git a/libcons/cons.h b/libcons/cons.h
index 783aeb6a..67f4e45b 100644
--- a/libcons/cons.h
+++ b/libcons/cons.h
@@ -189,7 +189,7 @@ void cons_vcons_scroll (vcons_t vcons, int delta);
 void cons_vcons_update (vcons_t vcons);
 
 /* The user must define this function.  Make the virtual console
-   VCONS, which is locked, beep audible.  */
+   VCONS, which is locked, beep audibly.  */
 void cons_vcons_beep (vcons_t vcons);
 
 /* The user must define this function.  Make the virtual console
@@ -218,8 +218,27 @@ void cons_vcons_remove (cons_t cons, vcons_list_t vcons_entry);
    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);
+/* Enter SIZE bytes from the buffer BUF into the virtual console
+   VCONS.  */
+error_t cons_vcons_input (vcons_t vcons, char *buf, size_t size);
+
+typedef enum
+  {
+    CONS_SCROLL_DELTA_LINES, CONS_SCROLL_DELTA_SCREENS,
+    CONS_SCROLL_ABSOLUTE_LINE, CONS_SCROLL_ABSOLUTE_PERCENTAGE
+  } cons_scroll_t;
+
+/* Scroll back into the history of VCONS.  If TYPE is
+   CONS_SCROLL_DELTA_LINES, scroll up or down by VALUE lines.  If TYPE
+   is CONS_SCROLL_DELTA_SCREENS, scroll up or down by VALUE multiples
+   of a screen height.  If TYPE is CONS_SCROLL_ABSOLUTE_LINE, scroll to
+   line VALUE (where 0 is the lowest line).  If TYPE is
+   CONS_SCROLL_ABSOLUTE_PERCENTAGE, scroll to the position determined
+   by VALUE, where 0 is the bottom and 1 is the top.
+
+   The function returns the number of lines actually scrolled up or
+   down.  */
+int cons_vcons_scrollback (vcons_t vcons, cons_scroll_t type, float value);
 
 
 extern const struct argp cons_startup_argp;
diff --git a/libcons/file-changed.c b/libcons/file-changed.c
index 2c91fe51..21449271 100644
--- a/libcons/file-changed.c
+++ b/libcons/file-changed.c
@@ -124,19 +124,28 @@ cons_S_file_changed (cons_notify_t notify, natural_t tickno,
 			scrolling = UINT32_MAX - vcons->state.screen.cur_line
 			  + 1 + new_cur_line;
 
-		      /* If we are scrollbacking, defer scrolling
+		      /* If we are scrolling back, defer scrolling
 			 until absolutely necessary.  */
 		      if (vcons->scrolling)
 			{
-			  if (vcons->scrolling + scrolling <= vcons->state.screen.scr_lines)
-			    {
-			      vcons->scrolling += scrolling;
-			      scrolling = 0;
-			    }
+			  if (_cons_jump_down_at_output)
+			    _cons_vcons_scrollback
+			      (vcons, CONS_SCROLL_ABSOLUTE_LINE, 0);
 			  else
 			    {
-			      scrolling -= vcons->state.screen.scr_lines - vcons->scrolling;
-			      vcons->scrolling = vcons->state.screen.scr_lines;
+			      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;
+				}
 			    }
 			}
 
@@ -225,6 +234,9 @@ 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->scrolling && _cons_jump_down_at_output)
+		_cons_vcons_scrollback (vcons, CONS_SCROLL_ABSOLUTE_LINE, 0);
+
 	      if (vcons->state.screen.cur_line >= vcons->scrolling)
 		rotate = vcons->state.screen.cur_line - vcons->scrolling;
 	      else
diff --git a/libcons/opts-std-startup.c b/libcons/opts-std-startup.c
index c4a7d7bd..f64f60fc 100644
--- a/libcons/opts-std-startup.c
+++ b/libcons/opts-std-startup.c
@@ -25,7 +25,9 @@
 
 
 /* Option keys for long-only options in diskfs_common_options.  */
-#define OPT_SLACK	600	/* --slack */
+#define OPT_SLACK		600	/* --slack */
+#define OPT_JUMP_DOWN_AT_INPUT	601	/* --jump-down-at-input */
+#define OPT_JUMP_DOWN_AT_OUTPUT	602	/* --jump-down-at-output */
 
 /* Common value for diskfs_common_options and diskfs_default_sync_interval. */
 #define DEFAULT_SLACK 100
@@ -37,6 +39,12 @@
    server.  */
 int _cons_slack = DEFAULT_SLACK;
 
+/* If we jump down at input.  */
+int _cons_jump_down_at_input;
+
+/* If we jump down at output.  */
+int _cons_jump_down_at_output;
+
 /* The filename of the console server.  */
 char *_cons_file;
 
@@ -45,6 +53,10 @@ startup_options[] =
 {
   { "slack", OPT_SLACK, "RECORDS", 0, "Max number of records the client is"
     " allowed to lag behind the server (default " DEFAULT_SLACK_STRING ")" },
+  { "jump-down-at-input", OPT_JUMP_DOWN_AT_INPUT, NULL, 0,
+    "End scrollback when something is entered" },
+  { "jump-down-at-output", OPT_JUMP_DOWN_AT_OUTPUT, NULL, 0,
+    "End scrollback when something is printed" },
   { 0, 0 }
 };
 
@@ -61,6 +73,14 @@ parse_startup_opt (int opt, char *arg, struct argp_state *state)
       _cons_slack = atoi (arg);
       break;
 
+    case OPT_JUMP_DOWN_AT_INPUT:
+      _cons_jump_down_at_input = 1;
+      break;
+
+    case OPT_JUMP_DOWN_AT_OUTPUT:
+      _cons_jump_down_at_output = 1;
+      break;
+
     case ARGP_KEY_ARG:
       if (state->arg_num > 0)
 	/* Too many arguments.  */
diff --git a/libcons/priv.h b/libcons/priv.h
index c99a1600..9f3fd7b6 100644
--- a/libcons/priv.h
+++ b/libcons/priv.h
@@ -25,10 +25,21 @@
    server.  */
 extern int _cons_slack;
 
+/* If we jump down at input.  */
+extern int _cons_jump_down_at_input;
+
+/* If we jump down at output.  */
+extern int _cons_jump_down_at_output;
+
 /* The filename of the console server.  */
 extern char *_cons_file;
 
 
+/* Non-locking version of cons_vcons_scrollback.  Does also not update
+   the display.  */
+int _cons_vcons_scrollback (vcons_t vcons, cons_scroll_t type, float value);
+
+
 /* Called by MiG to translate ports into cons_notify_t.  mutations.h
    arranges for this to happen for the fs_notify interfaces. */
 static inline cons_notify_t
diff --git a/libcons/vcons-input.c b/libcons/vcons-input.c
new file mode 100644
index 00000000..83cc8846
--- /dev/null
+++ b/libcons/vcons-input.c
@@ -0,0 +1,54 @@
+/* vcons-input.c - Add input to a virtual console.
+   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 <errno.h>
+#include <unistd.h>
+
+#include "cons.h"
+#include "priv.h"
+
+/* Enter SIZE bytes from the buffer BUF into the virtual console
+   VCONS.  */
+error_t
+cons_vcons_input (vcons_t vcons, char *buf, size_t size)
+{
+  int ret;
+
+  mutex_lock (&vcons->lock);
+
+  if (vcons->scrolling && _cons_jump_down_at_input)
+    _cons_vcons_scrollback (vcons, CONS_SCROLL_ABSOLUTE_LINE, 0);
+
+  do
+    {
+      ret = write (vcons->input, buf, size);
+      if (ret > 0)
+	{
+	  size -= ret;
+	  buf += ret;
+	}
+    }
+  while (size && (ret != -1 || errno == EINTR));
+
+  mutex_unlock (&vcons->lock);
+  return 0;
+}
+
+
diff --git a/libcons/vcons-scrollback.c b/libcons/vcons-scrollback.c
index cfc94458..84fef0b0 100644
--- a/libcons/vcons-scrollback.c
+++ b/libcons/vcons-scrollback.c
@@ -24,29 +24,43 @@
 
 #include "cons.h"
 
-/* Scroll back into the history of VCONS by DELTA lines.  */
+/* Non-locking version of cons_vcons_scrollback.  Does also not update
+   the display.  */
 int
-cons_vcons_scrollback (vcons_t vcons, int delta)
+_cons_vcons_scrollback (vcons_t vcons, cons_scroll_t type, float value)
 {
   int scrolling;
   uint32_t new_scr;
 
-  mutex_lock (&vcons->lock);
-  if (delta > 0 || vcons->scrolling > (uint32_t) (-delta))
+  switch (type)
     {
-      new_scr = vcons->scrolling + delta;
-      if (new_scr > vcons->state.screen.scr_lines)
-	new_scr = vcons->state.screen.scr_lines;
+    case CONS_SCROLL_DELTA_LINES:
+      scrolling = vcons->scrolling + ((uint32_t) value);
+      break;
+    case CONS_SCROLL_DELTA_SCREENS:
+      scrolling = vcons->scrolling
+	+ ((uint32_t) (value * vcons->state.screen.height));
+      break;
+    case CONS_SCROLL_ABSOLUTE_LINE:
+      scrolling = (uint32_t) value;
+      break;
+    case CONS_SCROLL_ABSOLUTE_PERCENTAGE:
+      scrolling = (uint32_t) (value * vcons->state.screen.scr_lines);
+      break;
+    default:
+      return 0;
     }
-  else
+
+  if (scrolling < 0)
     new_scr = 0;
+  else if (scrolling > vcons->state.screen.scr_lines)
+    new_scr = vcons->state.screen.scr_lines;
+  else
+    new_scr = scrolling;
 
   if (new_scr == vcons->scrolling)
-    {
-      mutex_unlock (&vcons->lock);
-      return 0;
-    }
-  
+    return 0;
+
   scrolling = vcons->scrolling - new_scr;
   {
     uint32_t new_cur_line;
@@ -114,9 +128,30 @@ cons_vcons_scrollback (vcons_t vcons, int delta)
       cons_vcons_set_cursor_status (vcons, CONS_CURSOR_INVISIBLE);
   }
 
-  cons_vcons_update (vcons);
   vcons->scrolling -= scrolling;
-  mutex_unlock (&vcons->lock);
 
   return -scrolling;
 }
+
+/* Scroll back into the history of VCONS.  If TYPE is
+   CONS_SCROLL_DELTA_LINES, scroll up or down by VALUE lines.  If TYPE
+   is CONS_SCROLL_DELTA_SCREENS, scroll up or down by VALUE multiples
+   of a screen height.  If TYPE is CONS_SCROLL_ABSOLUTE_LINE, scroll to
+   line VALUE (where 0 is the lowest line).  If TYPE is
+   CONS_SCROLL_ABSOLUTE_PERCENTAGE, scroll to the position determined
+   by VALUE, where 0 is the bottom and 1 is the top.
+
+   The function returns the number of lines actually scrolled up or
+   down.  */
+int
+cons_vcons_scrollback (vcons_t vcons, cons_scroll_t type, float value)
+{
+  int ret;
+
+  mutex_lock (&vcons->lock);
+  ret = _cons_vcons_scrollback (vcons, type, value);
+  cons_vcons_update (vcons);
+  mutex_unlock (&vcons->lock);
+  return ret;
+}
+