New file

2 files changed, 274 insertions, 0 deletions

diff --git a/etc/ChangeLog b/etc/ChangeLog
index c584240780..35c72c7b1a 100644
--- a/etc/ChangeLog
+++ b/etc/ChangeLog
@@ -1,3 +1,7 @@
+2005-05-30  Noah Friedman  <[email protected]>
+
+	* emacs-buffer.gdb: New file.
+
 2005-05-28  Richard M. Stallman  <[email protected]>
 
 	* TUTORIAL.fr: Change NBSP to space.
diff --git a/etc/emacs-buffer.gdb b/etc/emacs-buffer.gdb
new file mode 100644
index 0000000000..b99abe8a22
--- /dev/null
+++ b/etc/emacs-buffer.gdb
@@ -0,0 +1,270 @@
+# emacs-buffer.gdb --- gdb macros for recovering buffers from emacs coredumps
+
+# Copyright (C) 2005 Free Software Foundation, Inc.
+
+# Maintainer: Noah Friedman <[email protected]>
+# Status: tested with Emacs 22
+# Created: 2005-04-28
+
+# $Id$
+
+# This file is part of GNU Emacs.
+#
+# GNU Emacs 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.
+#
+# GNU Emacs 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 GNU Emacs; see the file COPYING.  If not, write to the
+# Free Software Foundation, Inc.; 51 Franklin Street, Fifth Floor;
+# Boston, MA 02110-1301, USA.
+
+# Commentary:
+
+# This is a set of gdb macros for recovering the contents of buffers from
+# an Emacs coredump; they may not always be file-backed or have a recent
+# autosave.
+#
+# The Emacs executable must have debugging symbols for this to work.  But
+# you never strip Emacs, right?  Right!
+#
+# The main commands of interest are `ybuffer-list', `yfile-buffers',
+# `ysave-buffer', and `ybuffer-contents'.  The `y' prefix avoids any
+# namespace collisions with emacs/src/.gdbinit.
+
+# Example usage:
+#
+#     $ gdb /export/src/emacs/2005-05-02--03-17/src/emacs core.emacs.6.9845
+#     Current directory is /u/noah/
+#     GNU gdb (6.1post-1.20040607.43rh)
+#     ...
+#     #0  0x400007a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
+#     (gdb) source emacs-buffer.gdb
+#     (gdb) ybuffer-list
+#     B# M       Size Name                 Mode       File
+#     -- -       ---- ----                 ----       ----
+#      0 *        556 mail to [email protected] Mail
+#      1 *          0  *Minibuf-1*         Fundamental
+#      2       145769 ChangeLog            Change Log /u/noah/lib/elisp/noahf/ChangeLog
+#      3         6619 ascii-table.el       Elisp      /u/noah/lib/elisp/noahf/ascii-table.el
+#      4 *      48396 *Messages*           Fundamental
+#      5         3191 *Apropos*            Apropos
+#      6        17642 init-21.el           Elisp      /u/noah/etc/init/emacs/init-21.el
+#      7          333 cpuid.c              C          /u/noah/cpuid.c
+#      8          230 src                  Dired
+#      9          218 noah                 Dired
+#     10 *         21  *Echo Area 0*       Fundamental
+#     11 *          0  *Echo Area 1*       Fundamental
+#     12       319952  *bbdb data*         Text       /u/noah/.bbdb
+#     (gdb) ysave-buffer 0 mail.save
+#     [Wrote buffer "mail to [email protected]" to file mail.save]
+#     (gdb) quit
+#     $ ls -l mail.save
+#     -rw-rw-rw-  1 noah user 556 May  2 04:05 mail.save
+#     $
+
+# Code:
+
+# Force loading of symbols, enough to give us gdb_valbits etc.
+set main
+
+# When nonzero, display some extra diagnostics in various commands
+set $yverbose = 1
+set $yfile_buffers_only = 0
+
+set $tagmask = (((long)1 << gdb_gctypebits) - 1)
+set $valmask = gdb_use_lsb ? ~($tagmask) : ((long)1 << gdb_valbits) - 1
+
+define ygetptr
+  set $ptr = $arg0
+  set $ptr = (gdb_use_union ? $ptr.u.val : $ptr & $valmask) | gdb_data_seg_bits
+end
+
+define ybuffer-list
+  set $files_only         = $yfile_buffers_only
+  set $yfile_buffers_only = 0
+
+  if $yverbose
+    printf "B# M       Size Name                 Mode       File\n"
+    printf "-- -       ---- ----                 ----       ----\n"
+  end
+
+  set $i = 0
+  set $alist = Vbuffer_alist
+  while $alist != Qnil
+    ygetptr $alist
+    set $this  = ((struct Lisp_Cons *) $ptr)->car
+    set $alist = ((struct Lisp_Cons *) $ptr)->cdr
+
+    # Vbuffer_alist elts are pairs of the form (name . buffer)
+    ygetptr $this
+    set $buf  = ((struct Lisp_Cons *) $ptr)->cdr
+    ygetptr $buf
+    set $buf = (struct buffer *) $ptr
+
+    if ! ($files_only && $buf->filename == Qnil)
+      ygetptr $buf->name
+      set $name = ((struct Lisp_String *) $ptr)->data
+      set $modp = ($buf->text->modiff > $buf->text->save_modiff) ? '*' : ' '
+
+      ygetptr $buf->mode_name
+      set $mode = ((struct Lisp_String *) $ptr)->data
+
+      if $buf->filename != Qnil
+        ygetptr $buf->filename
+        set $filename = ((struct Lisp_String *) $ptr)->data
+      else
+        set $filename = ' '
+      end
+
+      printf "%2d %c  %9d %-20s %-10s %s\n", \
+             $i, $modp, ($buf->text->z_byte - 1), $name, $mode, $filename
+    end
+
+    set $i++
+  end
+end
+document ybuffer-list
+  Display a list of buffer names, sizes, and other attributes.
+  The buffer number in the first column is used as an argument
+  to some other emacs-buffer recovery commands, e.g. `ysave-buffer'.
+end
+
+define yfile-buffers
+  set $yfile_buffers_only = 1
+  ybuffer-list
+end
+document yfile-buffers
+  Display a list of buffers which are associated with files.
+  This is like `ybuffer-list', but only buffers that were visiting files
+  are displayed.
+end
+
+define yset-buffer
+  set $i = $arg0
+
+  set $alist = Vbuffer_alist
+  while ($alist != Qnil && $i > 0)
+    ygetptr $alist
+    set $alist = ((struct Lisp_Cons *) $ptr)->cdr
+    set $i--
+  end
+
+  # Get car of alist; this is a pair (name . buffer)
+  ygetptr $alist
+  set $this = ((struct Lisp_Cons *) $ptr)->car
+
+  # Get the buffer object
+  ygetptr $this
+  set $this = ((struct Lisp_Cons *) $ptr)->cdr
+
+  ygetptr $this
+  set $ycurrent_buffer = (struct buffer *) $ptr
+end
+document yset-buffer
+  Set current buffer (for other emacs-buffer recovery commands) to the ARG'th
+  buffer as displayed by `ybuffer-list'.
+end
+
+define yget-buffer-pointers
+  yset-buffer $arg0
+  set $buf = $ycurrent_buffer->text
+
+  set $beg     = $buf->beg
+  set $gap     = $beg + $buf->gpt_byte
+  set $gap_end = $gap + $buf->gap_size - 1
+  set $end     = $gap_end + ($buf->z_byte - $buf->gpt_byte)
+
+  set $modp    = $buf->modiff > $buf->save_modiff
+
+  #print *$beg@($gap - $beg)
+  #print *$gap_end@($end - $gap_end)
+end
+document yget-buffer-pointers
+  Update convenience variables with address pointers for the ARG'th buffer
+  as displayed by `ybuffer-list'.
+
+  This also sets the current buffer using `yset-buffer' (which see).
+end
+
+define yget-current-buffer-name
+  set $this = $ycurrent_buffer->name
+  ygetptr $this
+  set $ycurrent_buffer_name = ((struct Lisp_String *) $ptr)->data
+end
+document yget-current-buffer-name
+  Set $ycurrent_buffer_name to the name of the currently selected buffer.
+end
+
+define ycurrent-buffer
+  yget-current-buffer-name
+  printf "%s\n", $ycurrent_buffer_name
+end
+document ycurrent-buffer
+  Display the currently selected buffer.
+end
+
+define ydump-buffer
+  yget-buffer-pointers $arg0
+  if $buf->z_byte > 1
+    if $buf->z_byte <= $buf->gpt_byte
+      set $endptr = $beg + $buf->gpt_byte - 1
+      dump binary memory $arg1 $beg $endptr
+    else
+      dump   binary memory $arg1 $beg $gap-1
+      append binary memory $arg1 $gap_end $end
+      set $endptr = $end
+    end
+  end
+end
+document ydump-buffer
+  Write contents of buffer N (as numbered according to `ybuffer-list') to
+  file FILE.
+
+  This is mainly used as an internal subroutine for `ysave-buffer' and
+  `ybuffer-contents', which see.
+end
+
+define ysave-buffer
+  ydump-buffer $arg0 $arg1
+  if $yverbose
+    yget-current-buffer-name
+    if $buf->z_byte <= 1
+      printf "[Buffer \"%s\" is empty.]\n", $ycurrent_buffer_name
+    else
+      # Output string broken into separate calls as necessary to avoid
+      # requiring a running process for evaluation.
+      printf "[Wrote buffer \"%s\" to file ", $ycurrent_buffer_name
+      echo $arg1]\n
+    end
+  end
+end
+document ysave-buffer
+  Save contents of buffer N (as numbered according to `ybuffer-list') to
+  file FILE.
+end
+
+define ybuffer-contents
+  ydump-buffer $arg0 /dev/stdout
+  if $yverbose && $buf->z_byte <= 1
+    yget-current-buffer-name
+    printf "[Buffer \"%s\" is empty.]\n", $ycurrent_buffer_name
+  else
+    if *($endptr-1) != '\n'
+      echo \n
+    end
+  end
+end
+document ybuffer-contents
+  Write contents of buffer N (numbered according to `ybuffer-list') to stdout.
+end
+
+# local variables:
+# mode: gdb-script
+# end: