view src/print.c @ 3895:a3c2418313d5

[xemacs-hg @ 2007-04-05 02:09:06 by stephent] Refactor separate_textual_runs, part 1 <87648fwhqx.fsf@uwakimon.sk.tsukuba.ac.jp>
author stephent
date Thu, 05 Apr 2007 02:09:08 +0000
parents d674024a8674
children d9eb5ea14f65
line wrap: on
line source

/* Lisp object printing and output streams.
   Copyright (C) 1985, 1986, 1988, 1992-1995 Free Software Foundation, Inc.
   Copyright (C) 1995, 1996, 2000, 2001, 2002, 2003, 2005 Ben Wing.

This file is part of XEmacs.

XEmacs 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.

XEmacs 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 XEmacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* Synched up with: Not synched with FSF. */

/* This file has been Mule-ized. */

/* Seriously divergent from FSF by this point.

   Seriously hacked on by Ben Wing for Mule.  All stdio code also by Ben,
   as well as the debugging code (initial version of debug_print(), though,
   by Jamie Zawinski) and the _fmt interfaces.  Also a fair amount of work
   by Hrvoje, e.g. floating-point code and rewriting to avoid O(N^2)
   consing when outputting to the echo area.  Print-circularity code by
   Martin? */

#include <config.h>
#include "lisp.h"

#include "backtrace.h"
#include "buffer.h"
#include "bytecode.h"
#include "device-impl.h"
#include "extents.h"
#include "frame.h"
#include "insdel.h"
#include "lstream.h"
#include "opaque.h"

#include "console-tty-impl.h"
#include "console-stream-impl.h"
#ifdef WIN32_NATIVE
#include "console-msw.h"
#endif

#include "sysfile.h"

#include <float.h>
/* Define if not in float.h */
#ifndef DBL_DIG
#define DBL_DIG 16
#endif

Lisp_Object Vstandard_output, Qstandard_output;

/* The subroutine object for external-debugging-output is kept here
   for the convenience of the debugger.  */
Lisp_Object Qexternal_debugging_output, Qalternate_debugging_output;

#ifdef HAVE_MS_WINDOWS
Lisp_Object Qmswindows_debugging_output;
#endif

/* Avoid actual stack overflow in print.  */
static int print_depth;

/* Detect most circularities to print finite output.  */
#define PRINT_CIRCLE 200
static Lisp_Object being_printed[PRINT_CIRCLE];

/* Maximum length of list or vector to print in full; noninteger means
   effectively infinity */

Lisp_Object Vprint_length;
Lisp_Object Qprint_length;

/* Maximum length of string to print in full; noninteger means
   effectively infinity */

Lisp_Object Vprint_string_length;
Lisp_Object Qprint_string_length;

/* Maximum depth of list to print in full; noninteger means
   effectively infinity.  */

Lisp_Object Vprint_level;

/* Label to use when making echo-area messages. */

Lisp_Object Vprint_message_label;

/* Nonzero means print newlines in strings as \n.  */

int print_escape_newlines;
int print_readably;

/* Non-nil means print #: before uninterned symbols.
   Neither t nor nil means so that and don't clear Vprint_gensym_alist
   on entry to and exit from print functions.  */
Lisp_Object Vprint_gensym;
Lisp_Object Vprint_gensym_alist;

Lisp_Object Qdisplay_error;
Lisp_Object Qprint_message_label;

/* Force immediate output of all printed data.  Used for debugging. */
int print_unbuffered;

FILE *termscript;	/* Stdio stream being used for copy of all output.  */

static void write_string_to_alternate_debugging_output (const Ibyte *str,
							Bytecount len);

/* To avoid consing in debug_prin1, we package up variables we need to bind
   into an opaque object. */
struct debug_bindings 
{
  int inhibit_non_essential_conversion_operations;
  int print_depth;
  int print_readably;
  int print_unbuffered;
  int gc_currently_forbidden;
  Lisp_Object Vprint_length;
  Lisp_Object Vprint_level;
  Lisp_Object Vinhibit_quit;
};

static Lisp_Object debug_prin1_bindings;


int stdout_needs_newline;
int stdout_clear_before_next_output;

/* Basic function to actually write to a stdio stream or TTY console. */

static void
write_string_to_stdio_stream_1 (FILE *stream, struct console *con,
				const Ibyte *ptr, Bytecount len,
				int must_flush)
{
  Extbyte *extptr = 0;
  Bytecount extlen = 0;
  int output_is_std_handle =
    stream ? stream == stdout || stream == stderr :
      CONSOLE_TTY_DATA (con)->is_stdio;

  if (stream || output_is_std_handle)
    {
      if (initialized && !inhibit_non_essential_conversion_operations)
	TO_EXTERNAL_FORMAT (DATA, (ptr, len),
			    ALLOCA, (extptr, extlen),
			    Qterminal);
      else
	{
#ifdef NON_ASCII_INTERNAL_FORMAT
#error Do something here
#else
	  extptr = (Extbyte *) ptr;
	  extlen = (Bytecount) len;
#endif
	}
    }

  if (stream)
    {
#ifdef WIN32_NATIVE
      HANDLE errhand = GetStdHandle (STD_INPUT_HANDLE);
      int no_useful_stderr = errhand == 0 || errhand == INVALID_HANDLE_VALUE;

      if (!no_useful_stderr)
	no_useful_stderr = !PeekNamedPipe (errhand, 0, 0, 0, 0, 0);
      /* we typically have no useful stdout/stderr under windows if we're
	 being invoked graphically. */
      if (no_useful_stderr)
	mswindows_output_console_string (ptr, len);
      else
#endif
	{
	  retry_fwrite (extptr, 1, extlen, stream);
#ifdef WIN32_NATIVE
	  /* Q122442 says that pipes are "treated as files, not as
	     devices", and that this is a feature. Before I found that
	     article, I thought it was a bug. Thanks MS, I feel much
	     better now. - kkm */
	  must_flush = 1;
#endif
	  if (must_flush)
	    fflush (stream);
	}
    }
  else
    /* The stream itself does conversion to external format */
    Lstream_write (XLSTREAM (CONSOLE_TTY_DATA (con)->outstream), ptr, len);

  if (output_is_std_handle)
    {
      if (termscript)
	{
	  retry_fwrite (extptr, 1, extlen, termscript);
	  fflush (termscript);
	}
      stdout_needs_newline = (ptr[len - 1] != '\n');
    }
}

/* Write to a stdio stream or TTY console, first clearing the left side
   if necessary. */

static void
write_string_to_stdio_stream (FILE *stream, struct console *con,
			      const Ibyte *ptr, Bytecount len,
			      int must_flush)
{
  if (stdout_clear_before_next_output &&
      (stream ? stream == stdout || stream == stderr :
       CONSOLE_TTY_DATA (con)->is_stdio))
    {
      if (stdout_needs_newline)
	write_string_to_stdio_stream_1 (stream, con, (Ibyte *) "\n", 1,
					must_flush);
      stdout_clear_before_next_output = 0;
    }

  write_string_to_stdio_stream_1 (stream, con, ptr, len, must_flush);
}

/*
    EXT_PRINT_STDOUT    = stdout or its equivalent (may be a
                          console window under MS Windows)
    EXT_PRINT_STDERR    = stderr or its equivalent (may be a
                          console window under MS Windows)
    EXT_PRINT_ALTERNATE = an internal character array; see
                          `alternate-debugging-output'
    EXT_PRINT_MSWINDOWS = Under MS Windows, the "debugging output" that
                          debuggers can hook into; uses OutputDebugString()
                          system call
    EXT_PRINT_ALL       = all of the above except stdout
*/

enum ext_print
  {
    EXT_PRINT_STDOUT = 1,
    EXT_PRINT_STDERR = 2,
    EXT_PRINT_ALTERNATE = 4,
    EXT_PRINT_MSWINDOWS = 8,
    EXT_PRINT_ALL = 14
  };

static void
write_string_to_external_output (const Ibyte *ptr, Bytecount len,
				 int dest)
{
  if (dest & EXT_PRINT_STDOUT)
    write_string_to_stdio_stream (stdout, 0, ptr, len, 1);
  if (dest & EXT_PRINT_STDERR)
    write_string_to_stdio_stream (stderr, 0, ptr, len, 1);
  if (dest & EXT_PRINT_ALTERNATE)
    write_string_to_alternate_debugging_output (ptr, len);
#ifdef WIN32_NATIVE
  if (dest & EXT_PRINT_MSWINDOWS)
    write_string_to_mswindows_debugging_output (ptr, len);
#endif
}

/* #### The following function should make use of a call to the
   emacs_vsprintf_*() functions rather than just using vsprintf.  This is
   the only way to ensure that I18N3 works properly (many implementations
   of the *printf() functions, including the ones included in glibc, do not
   implement the %###$ argument-positioning syntax).

   Note, however, that to do this, we'd have to

   1) pre-allocate all the lstreams and do whatever else was necessary
   to make sure that no allocation occurs, since these functions may be
   called from fatal_error_signal().

   2) (to be really correct) make a new lstream that outputs using
   mswindows_output_console_string().

   3) A reasonable compromise might be to use emacs_vsprintf() when we're
   in a safe state, and when not, use plain vsprintf(). */

static void
write_string_to_external_output_va (const CIbyte *fmt, va_list args,
				    int dest)
{
  Ibyte kludge[8192];
  Bytecount kludgelen;

  if (initialized && !inhibit_non_essential_conversion_operations)
    fmt = GETTEXT (fmt);
  vsprintf ((CIbyte *) kludge, fmt, args);
  kludgelen = qxestrlen (kludge);
  write_string_to_external_output (kludge, kludgelen, dest);
}

/* Output portably to stderr or its equivalent (i.e. may be a console
   window under MS Windows); do external-format conversion and call GETTEXT
   on the format string.  Automatically flush when done.

   NOTE: CIbyte means "internal format" data.  This includes the "..."
   arguments.  For numerical arguments, we have to assume that vsprintf
   will be a good boy and format them as ASCII.  For Mule internal coding
   (and UTF-8 internal coding, if/when we get it), it is safe to pass
   string values in internal format to be formatted, because zero octets
   only occur in the NUL character itself.  Similarly, it is safe to pass
   pure ASCII literal strings for these functions.  *Everything else must
   be converted, including all external data.*

   This function is safe to use even when not initialized or when dying --
   we don't do conversion in such cases. */

void
stderr_out (const CIbyte *fmt, ...)
{
  va_list args;
  va_start (args, fmt);
  write_string_to_external_output_va (fmt, args, EXT_PRINT_STDERR);
  va_end (args);
}

/* Output portably to stdout or its equivalent (i.e. may be a console
   window under MS Windows).  Works like stderr_out(). */

void
stdout_out (const CIbyte *fmt, ...)
{
  va_list args;
  va_start (args, fmt);
  write_string_to_external_output_va (fmt, args, EXT_PRINT_STDOUT);
  va_end (args);
}

/* Output portably to print destination as specified by DEST. */

void
external_out (int dest, const CIbyte *fmt, ...)
{
  va_list args;
  va_start (args, fmt);
  write_string_to_external_output_va (fmt, args, dest);
  va_end (args);
}

/* Output portably to stderr or its equivalent (i.e. may be a console
   window under MS Windows), as well as alternate-debugging-output and
   (under MS Windows) the C debugging output, i.e. OutputDebugString().
   Works like stderr_out(). */

void
debug_out (const CIbyte *fmt, ...)
{
  va_list args;
  va_start (args, fmt);
  write_string_to_external_output_va (fmt, args, EXT_PRINT_ALL);
  va_end (args);
}

DOESNT_RETURN
fatal (const CIbyte *fmt, ...)
{
  va_list args;
  va_start (args, fmt);

  stderr_out ("\nXEmacs: fatal error: ");
  write_string_to_external_output_va (fmt, args, EXT_PRINT_STDERR);
  stderr_out ("\n");

  va_end (args);
  exit (1);
}

/* Write a string to the output location specified in FUNCTION.
   Arguments NONRELOC, RELOC, OFFSET, and LEN are as in
   buffer_insert_string_1() in insdel.c.

   FUNCTION is one of

   -- an lstream
   -- a buffer (insert at point and advance point)
   -- a marker (insert at marker and advance marker)
   -- a frame (append to echo area; clear echo area first if
               `print-message-label' has changed since the last time)
   -- t or nil (send to stdout)
   -- a Lisp function of one argument (call to get data output)

   Use Qexternal_debugging_output to get output to stderr.
*/

static void
output_string (Lisp_Object function, const Ibyte *nonreloc,
	       Lisp_Object reloc, Bytecount offset, Bytecount len)
{
  /* This function can GC */
  Charcount cclen;
  /* We change the value of nonreloc (fetching it from reloc as
     necessary), but we don't want to pass this changed value on to
     other functions that take both a nonreloc and a reloc, or things
     may get confused and an assertion failure in
     fixup_internal_substring() may get triggered. */
  const Ibyte *newnonreloc = nonreloc;
  struct gcpro gcpro1, gcpro2;

  /* Emacs won't print while GCing, but an external debugger might */
#ifdef NO_PRINT_DURING_GC
  if (gc_in_progress) return;
#endif

  /* Perhaps not necessary but probably safer. */
  GCPRO2 (function, reloc);

  fixup_internal_substring (newnonreloc, reloc, offset, &len);

  if (STRINGP (reloc))
    {
      cclen = string_offset_byte_to_char_len (reloc, offset, len);
      newnonreloc = XSTRING_DATA (reloc);
    }
  else
    cclen = bytecount_to_charcount (newnonreloc + offset, len);

  if (LSTREAMP (function))
    {
      if (STRINGP (reloc))
	{
	  /* Protect against Lstream_write() causing a GC and
	     relocating the string.  For small strings, we do it by
	     alloc'ing the string and using a copy; for large strings,
	     we inhibit GC.  */
	  if (len < 65536)
	    {
	      Ibyte *copied = alloca_ibytes (len);
	      memcpy (copied, newnonreloc + offset, len);
	      Lstream_write (XLSTREAM (function), copied, len);
	    }
	  else if (gc_currently_forbidden)
	    {
	      /* Avoid calling begin_gc_forbidden, which conses.  We can reach
		 this point from the cons debug code, which will get us into
		 an infinite loop if we cons again. */
	      Lstream_write (XLSTREAM (function), newnonreloc + offset, len);
	    }
	  else
	    {
	      int speccount = begin_gc_forbidden ();
	      Lstream_write (XLSTREAM (function), newnonreloc + offset, len);
	      unbind_to (speccount);
	    }
	}
      else
	Lstream_write (XLSTREAM (function), newnonreloc + offset, len);

      if (print_unbuffered)
	Lstream_flush (XLSTREAM (function));
    }
  else if (BUFFERP (function))
    {
      CHECK_LIVE_BUFFER (function);
      buffer_insert_string (XBUFFER (function), nonreloc, reloc, offset, len);
    }
  else if (MARKERP (function))
    {
      /* marker_position() will err if marker doesn't point anywhere.  */
      Charbpos spoint = marker_position (function);

      buffer_insert_string_1 (XMARKER (function)->buffer,
			      spoint, nonreloc, reloc, offset, len,
			      0);
      Fset_marker (function, make_int (spoint + cclen),
		   Fmarker_buffer (function));
    }
  else if (FRAMEP (function))
    {
      /* This gets used by functions not invoking print_prepare(),
         such as Fwrite_char, Fterpri, etc..  */
      struct frame *f = XFRAME (function);
      CHECK_LIVE_FRAME (function);

      if (!EQ (Vprint_message_label, echo_area_status (f)))
	clear_echo_area_from_print (f, Qnil, 1);
      echo_area_append (f, nonreloc, reloc, offset, len, Vprint_message_label);
    }
  else if (EQ (function, Qt) || EQ (function, Qnil))
    {
      write_string_to_stdio_stream (stdout, 0, newnonreloc + offset, len,
				    print_unbuffered);
    }
  else if (EQ (function, Qexternal_debugging_output))
    {
      /* This is not strictly necessary, and somewhat of a hack, but it
	 avoids having each character passed separately to
	 `external-debugging-output'. #### Why do we pass each character
	 separately, anyway?
	 */
      write_string_to_stdio_stream (stderr, 0, newnonreloc + offset, len,
				    print_unbuffered);
    }
  else
    {
      Charcount ccoff;
      Charcount iii;

      if (STRINGP (reloc))
	ccoff = string_index_byte_to_char (reloc, offset);
      else
	ccoff = bytecount_to_charcount (newnonreloc, offset);

      if (STRINGP (reloc))
	{
	  for (iii = ccoff; iii < cclen + ccoff; iii++)
	    {
	      call1 (function, make_char (string_ichar (reloc, iii)));
	      if (STRINGP (reloc))
		newnonreloc = XSTRING_DATA (reloc);
	    }
	}
      else
	{
	  for (iii = ccoff; iii < cclen + ccoff; iii++)
	    {
	      call1 (function,
		     make_char (itext_ichar_n (newnonreloc, iii)));
	    }
	}
    }

  UNGCPRO;
}

#define RESET_PRINT_GENSYM do {			\
  if (!CONSP (Vprint_gensym))			\
    Vprint_gensym_alist = Qnil;			\
} while (0)

Lisp_Object
canonicalize_printcharfun (Lisp_Object printcharfun)
{
  if (NILP (printcharfun))
    printcharfun = Vstandard_output;

  if (!noninteractive && (EQ (printcharfun, Qt) || NILP (printcharfun)))
    printcharfun = Fselected_frame (Qnil); /* print to minibuffer */

  return printcharfun;
}

static Lisp_Object
print_prepare (Lisp_Object printcharfun, Lisp_Object *frame_kludge)
{
  /* Emacs won't print while GCing, but an external debugger might */
#ifdef NO_PRINT_DURING_GC
  if (gc_in_progress)
    return Qnil;
#endif
  
  RESET_PRINT_GENSYM;

  printcharfun = canonicalize_printcharfun (printcharfun);

  /* Here we could safely return the canonicalized PRINTCHARFUN.
     However, if PRINTCHARFUN is a frame, printing of complex
     structures becomes very expensive, because `append-message'
     (called by echo_area_append) gets called as many times as
     output_string() is called (and that's a *lot*).  append-message
     tries to keep top of the message-stack in sync with the contents
     of " *Echo Area" buffer, consing a new string for each component
     of the printed structure.  For instance, if you print (a a),
     append-message will cons up the following strings:

         "("
	 "(a"
	 "(a "
	 "(a a"
	 "(a a)"

     and will use only the last one.  With larger objects, this turns
     into an O(n^2) consing frenzy that locks up XEmacs in incessant
     garbage collection.

     We prevent this by creating a resizing_buffer stream and letting
     the printer write into it.  print_finish() will notice this
     stream, and invoke echo_area_append() with the stream's buffer,
     only once.  */
  if (FRAMEP (printcharfun))
    {
      CHECK_LIVE_FRAME (printcharfun);
      *frame_kludge = printcharfun;
      printcharfun = make_resizing_buffer_output_stream ();
    }

  return printcharfun;
}

static void
print_finish (Lisp_Object stream, Lisp_Object frame_kludge)
{
  /* Emacs won't print while GCing, but an external debugger might */
#ifdef NO_PRINT_DURING_GC
  if (gc_in_progress)
    return;
#endif
  
  RESET_PRINT_GENSYM;

  /* See the comment in print_prepare().  */
  if (FRAMEP (frame_kludge))
    {
      struct frame *f = XFRAME (frame_kludge);
      Lstream *str = XLSTREAM (stream);
      CHECK_LIVE_FRAME (frame_kludge);

      Lstream_flush (str);
      if (!EQ (Vprint_message_label, echo_area_status (f)))
	clear_echo_area_from_print (f, Qnil, 1);
      echo_area_append (f, resizing_buffer_stream_ptr (str),
			Qnil, 0, Lstream_byte_count (str),
			Vprint_message_label);
      Lstream_delete (str);
    }
}


/* Write internal-format data to STREAM.  See output_string() for
   interpretation of STREAM.

   NOTE: Do not call this with the data of a Lisp_String, as
   printcharfun might cause a GC, which might cause the string's data
   to be relocated.  To princ a Lisp string, use:

       print_internal (string, printcharfun, 0);

   Also note that STREAM should be the result of
   canonicalize_printcharfun() (i.e. Qnil means stdout, not
   Vstandard_output, etc.)  */
void
write_string_1 (Lisp_Object stream, const Ibyte *str, Bytecount size)
{
  /* This function can GC */
#ifdef ERROR_CHECK_TEXT
  assert (size >= 0);
#endif
  output_string (stream, str, Qnil, 0, size);
}

void
write_string (Lisp_Object stream, const Ibyte *str)
{
  /* This function can GC */
  write_string_1 (stream, str, qxestrlen (str));
}

void
write_c_string (Lisp_Object stream, const CIbyte *str)
{
  /* This function can GC */
  write_string_1 (stream, (const Ibyte *) str, strlen (str));
}

void
write_eistring (Lisp_Object stream, const Eistring *ei)
{
  write_string_1 (stream, eidata (ei), eilen (ei));
}

/* Write a printf-style string to STREAM; see output_string(). */

void
write_fmt_string (Lisp_Object stream, const CIbyte *fmt, ...)
{
  va_list va;
  Ibyte *str;
  Bytecount len;
  int count;

  va_start (va, fmt);
  str = emacs_vsprintf_malloc (fmt, va, &len);
  va_end (va);
  count = record_unwind_protect_freeing (str);
  write_string_1 (stream, str, len);
  unbind_to (count);
}

/* Write a printf-style string to STREAM, where the arguments are
   Lisp objects and not C strings or integers; see output_string().

   #### It shouldn't be necessary to specify the number of arguments.
   This would require some rewriting of the doprnt() functions, though. */

void
write_fmt_string_lisp (Lisp_Object stream, const CIbyte *fmt, int nargs, ...)
{
  Lisp_Object *args = alloca_array (Lisp_Object, nargs);
  va_list va;
  int i;
  Ibyte *str;
  Bytecount len;
  int count;

  va_start (va, nargs);
  for (i = 0; i < nargs; i++)
    args[i] = va_arg (va, Lisp_Object);
  va_end (va);
  str = emacs_vsprintf_malloc_lisp (fmt, Qnil, nargs, args, &len);
  count = record_unwind_protect_freeing (str);
  write_string_1 (stream, str, len);
  unbind_to (count);
}

void
stderr_out_lisp (const CIbyte *fmt, int nargs, ...)
{
  Lisp_Object *args = alloca_array (Lisp_Object, nargs);
  va_list va;
  int i;
  Ibyte *str;
  Bytecount len;
  int count;

  va_start (va, nargs);
  for (i = 0; i < nargs; i++)
    args[i] = va_arg (va, Lisp_Object);
  va_end (va);
  str = emacs_vsprintf_malloc_lisp (fmt, Qnil, nargs, args, &len);
  count = record_unwind_protect_freeing (str);
  write_string_1 (Qexternal_debugging_output, str, len);
  unbind_to (count);
}


DEFUN ("write-char", Fwrite_char, 1, 2, 0, /*
Output character CHARACTER to stream STREAM.
STREAM defaults to the value of `standard-output' (which see).
*/
       (character, stream))
{
  /* This function can GC */
  Ibyte str[MAX_ICHAR_LEN];
  Bytecount len;

  CHECK_CHAR_COERCE_INT (character);
  len = set_itext_ichar (str, XCHAR (character));
  output_string (canonicalize_printcharfun (stream), str, Qnil, 0, len);
  return character;
}

void
temp_output_buffer_setup (Lisp_Object bufname)
{
  /* This function can GC */
  struct buffer *old = current_buffer;
  Lisp_Object buf;

#ifdef I18N3
  /* #### This function should accept a Lisp_Object instead of a char *,
     so that proper translation on the buffer name can occur. */
#endif

  Fset_buffer (Fget_buffer_create (bufname));

  current_buffer->read_only = Qnil;
  Ferase_buffer (Qnil);

  buf = wrap_buffer (current_buffer);
  specbind (Qstandard_output, buf);

  set_buffer_internal (old);
}

Lisp_Object
internal_with_output_to_temp_buffer (Lisp_Object bufname,
                                     Lisp_Object (*function) (Lisp_Object arg),
                                     Lisp_Object arg,
                                     Lisp_Object same_frame)
{
  int speccount = specpdl_depth ();
  struct gcpro gcpro1, gcpro2, gcpro3;
  Lisp_Object buf = Qnil;

  GCPRO3 (buf, arg, same_frame);

  temp_output_buffer_setup (bufname);
  buf = Vstandard_output;

  arg = (*function) (arg);

  temp_output_buffer_show (buf, same_frame);
  UNGCPRO;

  return unbind_to_1 (speccount, arg);
}

DEFUN ("with-output-to-temp-buffer", Fwith_output_to_temp_buffer, 1, UNEVALLED, 0, /*
Bind `standard-output' to buffer BUFNAME, eval BODY, then show that buffer.
The buffer is cleared out initially, and marked as unmodified when done.
All output done by BODY is inserted in that buffer by default.
The buffer is displayed in another window, but not selected.
The value of the last form in BODY is returned.
If BODY does not finish normally, the buffer BUFNAME is not displayed.

If variable `temp-buffer-show-function' is non-nil, call it at the end
to get the buffer displayed.  It gets one argument, the buffer to display.
*/
       (args))
{
  /* This function can GC */
  Lisp_Object name = Qnil;
  int speccount = specpdl_depth ();
  struct gcpro gcpro1, gcpro2;
  Lisp_Object val = Qnil;

#ifdef I18N3
  /* #### should set the buffer to be translating.  See print_internal(). */
#endif

  GCPRO2 (name, val);
  name = Feval (XCAR (args));

  CHECK_STRING (name);

  temp_output_buffer_setup (name);
  UNGCPRO;

  val = Fprogn (XCDR (args));

  temp_output_buffer_show (Vstandard_output, Qnil);

  return unbind_to_1 (speccount, val);
}

DEFUN ("terpri", Fterpri, 0, 1, 0, /*
Output a newline to STREAM.
If STREAM is omitted or nil, the value of `standard-output' is used.
*/
       (stream))
{
  /* This function can GC */
  write_c_string (canonicalize_printcharfun (stream), "\n");
  return Qt;
}

DEFUN ("prin1", Fprin1, 1, 2, 0, /*
Output the printed representation of OBJECT, any Lisp object.
Quoting characters are printed when needed to make output that `read'
can handle, whenever this is possible.
Output stream is STREAM, or value of `standard-output' (which see).
*/
       (object, stream))
{
  /* This function can GC */
  Lisp_Object frame = Qnil;
  struct gcpro gcpro1, gcpro2;
  GCPRO2 (object, stream);

  stream = print_prepare (stream, &frame);
  print_internal (object, stream, 1);
  print_finish (stream, frame);

  UNGCPRO;
  return object;
}

DEFUN ("prin1-to-string", Fprin1_to_string, 1, 2, 0, /*
Return a string containing the printed representation of OBJECT,
any Lisp object.  Quoting characters are used when needed to make output
that `read' can handle, whenever this is possible, unless the optional
second argument NOESCAPE is non-nil.
*/
       (object, noescape))
{
  /* This function can GC */
  Lisp_Object result = Qnil;
  Lisp_Object stream = make_resizing_buffer_output_stream ();
  Lstream *str = XLSTREAM (stream);
  /* gcpro OBJECT in case a caller forgot to do so */
  struct gcpro gcpro1, gcpro2, gcpro3;
  GCPRO3 (object, stream, result);

  RESET_PRINT_GENSYM;
  print_internal (object, stream, NILP (noescape));
  RESET_PRINT_GENSYM;
  Lstream_flush (str);
  UNGCPRO;
  result = make_string (resizing_buffer_stream_ptr (str),
			Lstream_byte_count (str));
  Lstream_delete (str);
  return result;
}

DEFUN ("princ", Fprinc, 1, 2, 0, /*
Output the printed representation of OBJECT, any Lisp object.
No quoting characters are used; no delimiters are printed around
the contents of strings.
Output stream is STREAM, or value of `standard-output' (which see).
*/
       (object, stream))
{
  /* This function can GC */
  Lisp_Object frame = Qnil;
  struct gcpro gcpro1, gcpro2;

  GCPRO2 (object, stream);
  stream = print_prepare (stream, &frame);
  print_internal (object, stream, 0);
  print_finish (stream, frame);
  UNGCPRO;
  return object;
}

DEFUN ("print", Fprint, 1, 2, 0, /*
Output the printed representation of OBJECT, with newlines around it.
Quoting characters are printed when needed to make output that `read'
can handle, whenever this is possible.
Output stream is STREAM, or value of `standard-output' (which see).
*/
       (object, stream))
{
  /* This function can GC */
  Lisp_Object frame = Qnil;
  struct gcpro gcpro1, gcpro2;

  GCPRO2 (object, stream);
  stream = print_prepare (stream, &frame);
  write_c_string (stream, "\n");
  print_internal (object, stream, 1);
  write_c_string (stream, "\n");
  print_finish (stream, frame);
  UNGCPRO;
  return object;
}

/* Print an error message for the error DATA to STREAM.  This is a
   complete implementation of `display-error', which used to be in
   Lisp (see prim/cmdloop.el).  It was ported to C so it can be used
   efficiently by Ferror_message_string.  Fdisplay_error and
   Ferror_message_string are trivial wrappers around this function.

   STREAM should be the result of canonicalize_printcharfun().  */
static void
print_error_message (Lisp_Object error_object, Lisp_Object stream)
{
  /* This function can GC */
  Lisp_Object type = Fcar_safe (error_object);
  Lisp_Object method = Qnil;
  Lisp_Object tail;

  /* No need to GCPRO anything under the assumption that ERROR_OBJECT
     is GCPRO'd.  */

  if (! (CONSP (error_object) && SYMBOLP (type)
	 && CONSP (Fget (type, Qerror_conditions, Qnil))))
    goto error_throw;

  tail = XCDR (error_object);
  while (!NILP (tail))
    {
      if (CONSP (tail))
	tail = XCDR (tail);
      else
	goto error_throw;
    }
  tail = Fget (type, Qerror_conditions, Qnil);
  while (!NILP (tail))
    {
      if (!(CONSP (tail) && SYMBOLP (XCAR (tail))))
	goto error_throw;
      else if (!NILP (Fget (XCAR (tail), Qdisplay_error, Qnil)))
	{
	  method = Fget (XCAR (tail), Qdisplay_error, Qnil);
	  goto error_throw;
	}
      else
	tail = XCDR (tail);
    }
  /* Default method */
  {
    int first = 1;
    int speccount = specpdl_depth ();
    Lisp_Object frame = Qnil;
    struct gcpro gcpro1;
    GCPRO1 (stream);

    specbind (Qprint_message_label, Qerror);
    stream = print_prepare (stream, &frame);

    tail = Fcdr (error_object);
    if (EQ (type, Qerror))
      {
	print_internal (Fcar (tail), stream, 0);
	tail = Fcdr (tail);
      }
    else
      {
	Lisp_Object errmsg = Fget (type, Qerror_message, Qnil);
	if (NILP (errmsg))
	  print_internal (type, stream, 0);
	else
	  print_internal (LISP_GETTEXT (errmsg), stream, 0);
      }
    while (!NILP (tail))
      {
	write_c_string (stream, first ? ": " : ", ");
	/* Most errors have an explanatory string as their first argument,
	   and it looks better not to put the quotes around it. */
	print_internal (Fcar (tail), stream,
			!(first && STRINGP (Fcar (tail))) ||
			!NILP (Fget (type, Qerror_lacks_explanatory_string,
				     Qnil)));
	tail = Fcdr (tail);
	first = 0;
      }
    print_finish (stream, frame);
    UNGCPRO;
    unbind_to (speccount);
    return;
    /* not reached */
  }

 error_throw:
  if (NILP (method))
    {
      write_c_string (stream, GETTEXT ("Peculiar error "));
      print_internal (error_object, stream, 1);
      return;
    }
  else
    {
      call2 (method, error_object, stream);
    }
}

DEFUN ("error-message-string", Ferror_message_string, 1, 1, 0, /*
Convert ERROR-OBJECT to an error message, and return it.

The format of ERROR-OBJECT should be (ERROR-SYMBOL . DATA).  The
message is equivalent to the one that would be issued by
`display-error' with the same argument.
*/
       (error_object))
{
  /* This function can GC */
  Lisp_Object result = Qnil;
  Lisp_Object stream = make_resizing_buffer_output_stream ();
  struct gcpro gcpro1;
  GCPRO1 (stream);

  print_error_message (error_object, stream);
  Lstream_flush (XLSTREAM (stream));
  result = make_string (resizing_buffer_stream_ptr (XLSTREAM (stream)),
			Lstream_byte_count (XLSTREAM (stream)));
  Lstream_delete (XLSTREAM (stream));

  UNGCPRO;
  return result;
}

DEFUN ("display-error", Fdisplay_error, 2, 2, 0, /*
Display ERROR-OBJECT on STREAM in a user-friendly way.
*/
       (error_object, stream))
{
  /* This function can GC */
  print_error_message (error_object, canonicalize_printcharfun (stream));
  return Qnil;
}


Lisp_Object Vfloat_output_format;

/*
 * This buffer should be at least as large as the max string size of the
 * largest float, printed in the biggest notation.  This is undoubtedly
 * 20d float_output_format, with the negative of the C-constant "HUGE"
 * from <math.h>.
 *
 * On the vax the worst case is -1e38 in 20d format which takes 61 bytes.
 *
 * I assume that IEEE-754 format numbers can take 329 bytes for the worst
 * case of -1e307 in 20d float_output_format. What is one to do (short of
 * re-writing _doprnt to be more sane)?
 * 			-wsr
 */
void
float_to_string (char *buf, double data)
{
  Ibyte *cp, c;
  int width;

  if (NILP (Vfloat_output_format)
      || !STRINGP (Vfloat_output_format))
  lose:
    sprintf (buf, "%.16g", data);
  else			/* oink oink */
    {
      /* Check that the spec we have is fully valid.
	 This means not only valid for printf,
	 but meant for floats, and reasonable.  */
      cp = XSTRING_DATA (Vfloat_output_format);

      if (cp[0] != '%')
	goto lose;
      if (cp[1] != '.')
	goto lose;

      cp += 2;
      for (width = 0; (c = *cp, isdigit (c)); cp++)
	{
	  width *= 10;
	  width += c - '0';
	}

      if (*cp != 'e' && *cp != 'f' && *cp != 'g' && *cp != 'E' && *cp != 'G')
	goto lose;

      if (width < (int) (*cp != 'e' && *cp != 'E') || width > DBL_DIG)
	goto lose;

      if (cp[1] != 0)
	goto lose;

      sprintf (buf, (char *) XSTRING_DATA (Vfloat_output_format),
	       data);
    }

  /* added by jwz: don't allow "1.0" to print as "1"; that destroys
     the read-equivalence of lisp objects.  (* x 1) and (* x 1.0) do
     not do the same thing, so it's important that the printed
     representation of that form not be corrupted by the printer.
   */
  {
    Ibyte *s = (Ibyte *) buf; /* don't use signed chars here!
				     isdigit() can't hack them! */
    if (*s == '-') s++;
    for (; *s; s++)
      /* if there's a non-digit, then there is a decimal point, or
	 it's in exponential notation, both of which are ok. */
      if (!isdigit (*s))
	goto DONE_LABEL;
    /* otherwise, we need to hack it. */
    *s++ = '.';
    *s++ = '0';
    *s = 0;
  }
 DONE_LABEL:

  /* Some machines print "0.4" as ".4".  I don't like that. */
  if (buf [0] == '.' || (buf [0] == '-' && buf [1] == '.'))
    {
      int i;
      for (i = strlen (buf) + 1; i >= 0; i--)
	buf [i+1] = buf [i];
      buf [(buf [0] == '-' ? 1 : 0)] = '0';
    }
}

#define ONE_DIGIT(figure) *p++ = (char) (n / (figure) + '0')
#define ONE_DIGIT_ADVANCE(figure) (ONE_DIGIT (figure), n %= (figure))

#define DIGITS_1(figure) ONE_DIGIT (figure)
#define DIGITS_2(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_1 ((figure) / 10)
#define DIGITS_3(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_2 ((figure) / 10)
#define DIGITS_4(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_3 ((figure) / 10)
#define DIGITS_5(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_4 ((figure) / 10)
#define DIGITS_6(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_5 ((figure) / 10)
#define DIGITS_7(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_6 ((figure) / 10)
#define DIGITS_8(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_7 ((figure) / 10)
#define DIGITS_9(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_8 ((figure) / 10)
#define DIGITS_10(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_9 ((figure) / 10)

/* DIGITS_<11-20> are only used on machines with 64-bit longs. */

#define DIGITS_11(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_10 ((figure) / 10)
#define DIGITS_12(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_11 ((figure) / 10)
#define DIGITS_13(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_12 ((figure) / 10)
#define DIGITS_14(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_13 ((figure) / 10)
#define DIGITS_15(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_14 ((figure) / 10)
#define DIGITS_16(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_15 ((figure) / 10)
#define DIGITS_17(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_16 ((figure) / 10)
#define DIGITS_18(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_17 ((figure) / 10)
#define DIGITS_19(figure) ONE_DIGIT_ADVANCE (figure); DIGITS_18 ((figure) / 10)

/* Print NUMBER to BUFFER in base 10.  This is completely equivalent
   to `sprintf(buffer, "%ld", number)', only much faster.

   The speedup may make a difference in programs that frequently
   convert numbers to strings.  Some implementations of sprintf,
   particularly the one in GNU libc, have been known to be extremely
   slow compared to this function.

   BUFFER should accept as many bytes as you expect the number to take
   up.  On machines with 64-bit longs the maximum needed size is 24
   bytes.  That includes the worst-case digits, the optional `-' sign,
   and the trailing \0.  */

void
long_to_string (char *buffer, long number)
{
  char *p = buffer;
  long n = number;

#if (SIZEOF_LONG != 4) && (SIZEOF_LONG != 8)
  /* We are running in a strange or misconfigured environment.  Let
     sprintf cope with it.  */
  sprintf (buffer, "%ld", n);
#else  /* (SIZEOF_LONG == 4) || (SIZEOF_LONG == 8) */

  if (n < 0)
    {
      *p++ = '-';
      n = -n;
    }

  if      (n < 10)                   { DIGITS_1 (1); }
  else if (n < 100)                  { DIGITS_2 (10); }
  else if (n < 1000)                 { DIGITS_3 (100); }
  else if (n < 10000)                { DIGITS_4 (1000); }
  else if (n < 100000)               { DIGITS_5 (10000); }
  else if (n < 1000000)              { DIGITS_6 (100000); }
  else if (n < 10000000)             { DIGITS_7 (1000000); }
  else if (n < 100000000)            { DIGITS_8 (10000000); }
  else if (n < 1000000000)           { DIGITS_9 (100000000); }
#if SIZEOF_LONG == 4
  /* ``if (1)'' serves only to preserve editor indentation. */
  else if (1)                        { DIGITS_10 (1000000000); }
#else  /* SIZEOF_LONG != 4 */
  else if (n < 10000000000L)         { DIGITS_10 (1000000000L); }
  else if (n < 100000000000L)        { DIGITS_11 (10000000000L); }
  else if (n < 1000000000000L)       { DIGITS_12 (100000000000L); }
  else if (n < 10000000000000L)      { DIGITS_13 (1000000000000L); }
  else if (n < 100000000000000L)     { DIGITS_14 (10000000000000L); }
  else if (n < 1000000000000000L)    { DIGITS_15 (100000000000000L); }
  else if (n < 10000000000000000L)   { DIGITS_16 (1000000000000000L); }
  else if (n < 100000000000000000L)  { DIGITS_17 (10000000000000000L); }
  else if (n < 1000000000000000000L) { DIGITS_18 (100000000000000000L); }
  else                               { DIGITS_19 (1000000000000000000L); }
#endif /* SIZEOF_LONG != 4 */

  *p = '\0';
#endif /* (SIZEOF_LONG == 4) || (SIZEOF_LONG == 8) */
}

#undef ONE_DIGIT
#undef ONE_DIGIT_ADVANCE

#undef DIGITS_1
#undef DIGITS_2
#undef DIGITS_3
#undef DIGITS_4
#undef DIGITS_5
#undef DIGITS_6
#undef DIGITS_7
#undef DIGITS_8
#undef DIGITS_9
#undef DIGITS_10
#undef DIGITS_11
#undef DIGITS_12
#undef DIGITS_13
#undef DIGITS_14
#undef DIGITS_15
#undef DIGITS_16
#undef DIGITS_17
#undef DIGITS_18
#undef DIGITS_19

static void
print_vector_internal (const char *start, const char *end,
                       Lisp_Object obj,
                       Lisp_Object printcharfun, int escapeflag)
{
  /* This function can GC */
  int i;
  int len = XVECTOR_LENGTH (obj);
  int last = len;
  struct gcpro gcpro1, gcpro2;
  GCPRO2 (obj, printcharfun);

  if (INTP (Vprint_length))
    {
      int max = XINT (Vprint_length);
      if (max < len) last = max;
    }

  write_c_string (printcharfun, start);
  for (i = 0; i < last; i++)
    {
      Lisp_Object elt = XVECTOR_DATA (obj)[i];
      if (i != 0) write_c_string (printcharfun, " ");
      print_internal (elt, printcharfun, escapeflag);
    }
  UNGCPRO;
  if (last != len)
    write_c_string (printcharfun, " ...");
  write_c_string (printcharfun, end);
}

void
print_cons (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
  /* This function can GC */
  struct gcpro gcpro1, gcpro2;

  /* If print_readably is on, print (quote -foo-) as '-foo-
     (Yeah, this should really be what print-pretty does, but we
     don't have the rest of a pretty printer, and this actually
     has non-negligible impact on size/speed of .elc files.)
  */
  if (print_readably &&
      EQ (XCAR (obj), Qquote) &&
      CONSP (XCDR (obj)) &&
      NILP (XCDR (XCDR (obj))))
    {
      obj = XCAR (XCDR (obj));
      GCPRO2 (obj, printcharfun);
      write_c_string (printcharfun, "\'");
      UNGCPRO;
      print_internal (obj, printcharfun, escapeflag);
      return;
    }

  GCPRO2 (obj, printcharfun);
  write_c_string (printcharfun, "(");

  {
    int len;
    int max = INTP (Vprint_length) ? XINT (Vprint_length) : INT_MAX;
    Lisp_Object tortoise;
    /* Use tortoise/hare to make sure circular lists don't infloop */

    for (tortoise = obj, len = 0;
	 CONSP (obj);
	 obj = XCDR (obj), len++)
      {
	if (len > 0)
	  write_c_string (printcharfun, " ");
	if (EQ (obj, tortoise) && len > 0)
	  {
	    if (print_readably)
	      printing_unreadable_object ("circular list");
	    else
	      write_c_string (printcharfun, "... <circular list>");
	    break;
	  }
	if (len & 1)
	  tortoise = XCDR (tortoise);
	if (len > max)
	  {
	    write_c_string (printcharfun, "...");
	    break;
	  }
	print_internal (XCAR (obj), printcharfun, escapeflag);
      }
  }
  if (!LISTP (obj))
    {
      write_c_string (printcharfun, " . ");
      print_internal (obj, printcharfun, escapeflag);
    }
  UNGCPRO;

  write_c_string (printcharfun, ")");
  return;
}

void
print_vector (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
  print_vector_internal ("[", "]", obj, printcharfun, escapeflag);
}

void
print_string (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
  /* We distinguish between Bytecounts and Charcounts, to make
     Vprint_string_length work correctly under Mule.  */
  Charcount size = string_char_length (obj);
  Charcount max = size;
  Bytecount bcmax = XSTRING_LENGTH (obj);
  struct gcpro gcpro1, gcpro2;
  GCPRO2 (obj, printcharfun);

  if (INTP (Vprint_string_length) &&
      XINT (Vprint_string_length) < max)
    {
      max = XINT (Vprint_string_length);
      bcmax = string_index_char_to_byte (obj, max);
    }
  if (max < 0)
    {
      max = 0;
      bcmax = 0;
    }

  if (!escapeflag)
    {
      /* This deals with GC-relocation and Mule. */
      output_string (printcharfun, 0, obj, 0, bcmax);
      if (max < size)
	write_c_string (printcharfun, " ...");
    }
  else
    {
      Bytecount i, last = 0;

      write_c_string (printcharfun, "\"");
      for (i = 0; i < bcmax; i++)
	{
	  Ibyte ch = string_byte (obj, i);
	  if (ch == '\"' || ch == '\\'
	      || (ch == '\n' && print_escape_newlines))
	    {
	      if (i > last)
		{
		  output_string (printcharfun, 0, obj, last,
				 i - last);
		}
	      if (ch == '\n')
		{
		  write_c_string (printcharfun, "\\n");
		}
	      else
		{
		  Ibyte temp[2];
		  write_c_string (printcharfun, "\\");
		  /* This is correct for Mule because the
		     character is either \ or " */
		  temp[0] = string_byte (obj, i);
		  temp[1] = '\0';
		  write_string (printcharfun, temp);
		}
	      last = i + 1;
	    }
	}
      if (bcmax > last)
	{
	  output_string (printcharfun, 0, obj, last,
			 bcmax - last);
	}
      if (max < size)
	write_c_string (printcharfun, " ...");
      write_c_string (printcharfun, "\"");
    }
  UNGCPRO;
}

void
default_object_printer (Lisp_Object obj, Lisp_Object printcharfun,
			int UNUSED (escapeflag))
{
  struct LCRECORD_HEADER *header = (struct LCRECORD_HEADER *) XPNTR (obj);

  if (print_readably)
    printing_unreadable_object
      ("#<%s 0x%x>",
#ifdef NEW_GC
       LHEADER_IMPLEMENTATION (header)->name,
#else /* not NEW_GC */
       LHEADER_IMPLEMENTATION (&header->lheader)->name,
#endif /* not NEW_GC */
       header->uid);

  write_fmt_string (printcharfun, "#<%s 0x%x>",
#ifdef NEW_GC
		    LHEADER_IMPLEMENTATION (header)->name,
#else /* not NEW_GC */
		    LHEADER_IMPLEMENTATION (&header->lheader)->name,
#endif /* not NEW_GC */
		    header->uid);
}

void
internal_object_printer (Lisp_Object obj, Lisp_Object printcharfun,
			 int UNUSED (escapeflag))
{
  write_fmt_string (printcharfun,
		    "#<INTERNAL OBJECT (XEmacs bug?) (%s) 0x%lx>",
		    XRECORD_LHEADER_IMPLEMENTATION (obj)->name,
		    (unsigned long) XPNTR (obj));
}

enum printing_badness
{
  BADNESS_INTEGER_OBJECT,
  BADNESS_POINTER_OBJECT,
  BADNESS_NO_TYPE
};

static void
printing_major_badness (Lisp_Object printcharfun,
			Ascbyte *badness_string, int type, void *val,
			enum printing_badness badness)
{
  Ibyte buf[666];

  switch (badness)
    {
    case BADNESS_INTEGER_OBJECT:
      qxesprintf (buf, "%s %d object %ld", badness_string, type,
		  (EMACS_INT) val);
      break;

    case BADNESS_POINTER_OBJECT:
      qxesprintf (buf, "%s %d object %p", badness_string, type, val);
      break;

    case BADNESS_NO_TYPE:
      qxesprintf (buf, "%s object %p", badness_string, val);
      break;
    }

  /* Don't abort or signal if called from debug_print() or already
     crashing */
  if (!inhibit_non_essential_conversion_operations)
    {
#ifdef ERROR_CHECK_TYPES
      ABORT ();
#else  /* not ERROR_CHECK_TYPES */
      if (print_readably)
	signal_ferror (Qinternal_error, "printing %s", buf);
#endif /* not ERROR_CHECK_TYPES */
    }
  write_fmt_string (printcharfun,
		    "#<EMACS BUG: %s Save your buffers immediately and "
		    "please report this bug>", buf);
}

void
print_internal (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
  /* This function can GC */
  int specdepth = 0;
  struct gcpro gcpro1, gcpro2;

  QUIT;

#ifdef NO_PRINT_DURING_GC
  /* Emacs won't print while GCing, but an external debugger might */
  if (gc_in_progress) return;
#endif

  /* Just to be safe ... */
  GCPRO2 (obj, printcharfun);

#ifdef I18N3
  /* #### Both input and output streams should have a flag associated
     with them indicating whether output to that stream, or strings
     read from the stream, get translated using Fgettext().  Such a
     stream is called a "translating stream".  For the minibuffer and
     external-debugging-output this is always true on output, and
     with-output-to-temp-buffer sets the flag to true for the buffer
     it creates.  This flag should also be user-settable.  Perhaps it
     should be split up into two flags, one for input and one for
     output. */
#endif

  /* Detect circularities and truncate them.
     No need to offer any alternative--this is better than an error.  */
  if (CONSP (obj) || VECTORP (obj) || COMPILED_FUNCTIONP (obj))
    {
      int i;
      for (i = 0; i < print_depth; i++)
	if (EQ (obj, being_printed[i]))
	  {
	    char buf[DECIMAL_PRINT_SIZE (long) + 1];
	    *buf = '#';
	    long_to_string (buf + 1, i);
	    write_c_string (printcharfun, buf);
	    UNGCPRO;
	    return;
	  }
    }

  being_printed[print_depth] = obj;

  /* Avoid calling internal_bind_int, which conses, when called from
     debug_prin1.  In that case, we have bound print_depth to 0 anyway. */
  if (!inhibit_non_essential_conversion_operations)
    {
      specdepth = internal_bind_int (&print_depth, print_depth + 1);

      if (print_depth > PRINT_CIRCLE)
	signal_error (Qstack_overflow, "Apparently circular structure being printed", Qunbound);
    }

  switch (XTYPE (obj))
    {
    case Lisp_Type_Int_Even:
    case Lisp_Type_Int_Odd:
      {
	char buf[DECIMAL_PRINT_SIZE (EMACS_INT)];
	long_to_string (buf, XINT (obj));
	write_c_string (printcharfun, buf);
	break;
      }

    case Lisp_Type_Char:
      {
	/* God intended that this be #\..., you know. */
	char buf[16];
	Ichar ch = XCHAR (obj);
	char *p = buf;
	*p++ = '?';
	if (ch < 32)
	  {
	    *p++ = '\\';
	    switch (ch)
	      {
	      case '\t': *p++ = 't'; break;
	      case '\n': *p++ = 'n'; break;
	      case '\r': *p++ = 'r'; break;
	      default:
		*p++ = '^';
		*p++ = ch + 64;
		if ((ch + 64) == '\\')
		  *p++ = '\\';
		break;
	      }
	  }
	else if (ch < 127)
	  {
	    /* syntactically special characters should be escaped. */
	    switch (ch)
	      {
	      case ' ':
	      case '"':
	      case '#':
	      case '\'':
	      case '(':
	      case ')':
	      case ',':
	      case '.':
	      case ';':
	      case '?':
	      case '[':
	      case '\\':
	      case ']':
	      case '`':
		*p++ = '\\';
	      }
	    *p++ = ch;
	  }
	else if (ch == 127)
	  {
	    *p++ = '\\', *p++ = '^', *p++ = '?';
	  }
	else if (ch < 160)
	  {
	    *p++ = '\\', *p++ = '^';
	    p += set_itext_ichar ((Ibyte *) p, ch + 64);
	  }
	else
	  {
	    p += set_itext_ichar ((Ibyte *) p, ch);
	  }

	output_string (printcharfun, (Ibyte *) buf, Qnil, 0, p - buf);

	break;
      }

    case Lisp_Type_Record:
      {
	struct lrecord_header *lheader = XRECORD_LHEADER (obj);

	/* Try to check for various sorts of bogus pointers if we're in a
	   situation where it may be likely -- i.e. called from
	   debug_print() or we're already crashing.  In such cases,
	   (further) crashing is counterproductive. */

	if (inhibit_non_essential_conversion_operations &&
	    !debug_can_access_memory (lheader, sizeof (*lheader)))
	    {
	      write_fmt_string (printcharfun, "#<EMACS BUG: BAD MEMORY %p>",
				lheader);
	      break;
	    }

	if (CONSP (obj) || VECTORP (obj))
	  {
	    /* If deeper than spec'd depth, print placeholder.  */
	    if (INTP (Vprint_level)
		&& print_depth > XINT (Vprint_level))
	      {
		write_c_string (printcharfun, "...");
		break;
	      }
	  }

#ifndef NEW_GC
	if (lheader->type == lrecord_type_free)
	  {
	    printing_major_badness (printcharfun, "freed lrecord", 0,
				    lheader, BADNESS_NO_TYPE);
	    break;
	  }
	else if (lheader->type == lrecord_type_undefined)
	  {
	    printing_major_badness (printcharfun, "lrecord_type_undefined", 0,
				    lheader, BADNESS_NO_TYPE);
	    break;
	  }
#endif /* not NEW_GC */
	else if ((int) (lheader->type) >= lrecord_type_count)
	  {
	    printing_major_badness (printcharfun, "illegal lrecord type",
				    (int) (lheader->type),
				    lheader, BADNESS_POINTER_OBJECT);
	    break;
	  }

	/* Further checks for bad memory in critical situations.  We don't
	   normally do these because they may be expensive or weird
	   (e.g. under Unix we typically have to set a SIGSEGV handler and
	   try to trigger a seg fault). */

	if (inhibit_non_essential_conversion_operations)
	  {
	    if (!debug_can_access_memory
		(lheader, detagged_lisp_object_size (lheader)))
	      {
		write_fmt_string (printcharfun,
				  "#<EMACS BUG: type %s BAD MEMORY %p>",
				  LHEADER_IMPLEMENTATION (lheader)->name,
				  lheader);
		break;
	      }

	    if (STRINGP (obj))
	      {
#ifdef NEW_GC
		if (!debug_can_access_memory (XSTRING_DATA (obj), 
					      XSTRING_LENGTH (obj)))
		  {
		    write_fmt_string
		      (printcharfun,
		       "#<EMACS BUG: %p (BAD STRING DATA %p)>",
		       lheader, XSTRING_DATA (obj));
		    break;
		  }
#else /* not NEW_GC */
		Lisp_String *l = (Lisp_String *) lheader;
		if (!debug_can_access_memory (l->data_, l->size_))
		  {
		    write_fmt_string
		      (printcharfun,
		       "#<EMACS BUG: %p (BAD STRING DATA %p)>",
		       lheader, l->data_);
		    break;
		  }
#endif /* not NEW_GC */
	      }
	  }

	if (LHEADER_IMPLEMENTATION (lheader)->printer)
	  ((LHEADER_IMPLEMENTATION (lheader)->printer)
	   (obj, printcharfun, escapeflag));
	else
	  internal_object_printer (obj, printcharfun, escapeflag);
	break;
      }

    default:
      {
	/* We're in trouble if this happens! */
	printing_major_badness (printcharfun, "illegal data type", XTYPE (obj),
				LISP_TO_VOID (obj), BADNESS_INTEGER_OBJECT);
	break;
      }
    }

  if (!inhibit_non_essential_conversion_operations)
    unbind_to (specdepth);
  UNGCPRO;
}

void
print_float (Lisp_Object obj, Lisp_Object printcharfun,
	     int UNUSED (escapeflag))
{
  char pigbuf[350];	/* see comments in float_to_string */

  float_to_string (pigbuf, XFLOAT_DATA (obj));
  write_c_string (printcharfun, pigbuf);
}

void
print_symbol (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
  /* This function can GC */
  /* #### Bug!! (intern "") isn't printed in some distinguished way */
  /* ####  (the reader also loses on it) */
  Lisp_Object name = symbol_name (XSYMBOL (obj));
  Bytecount size = XSTRING_LENGTH (name);
  struct gcpro gcpro1, gcpro2;

  if (!escapeflag)
    {
      /* This deals with GC-relocation */
      output_string (printcharfun, 0, name, 0, size);
      return;
    }
  GCPRO2 (obj, printcharfun);

  /* If we print an uninterned symbol as part of a complex object and
     the flag print-gensym is non-nil, prefix it with #n= to read the
     object back with the #n# reader syntax later if needed.  */
  if (!NILP (Vprint_gensym)
      /* #### Test whether this produces a noticeable slow-down for
         printing when print-gensym is non-nil.  */
      && !EQ (obj, oblookup (Vobarray,
			     XSTRING_DATA (symbol_name (XSYMBOL (obj))),
			     XSTRING_LENGTH (symbol_name (XSYMBOL (obj))))))
    {
      if (print_depth > 1)
	{
	  Lisp_Object tem = Fassq (obj, Vprint_gensym_alist);
	  if (CONSP (tem))
	    {
	      write_c_string (printcharfun, "#");
	      print_internal (XCDR (tem), printcharfun, escapeflag);
	      write_c_string (printcharfun, "#");
	      UNGCPRO;
	      return;
	    }
	  else
	    {
	      if (CONSP (Vprint_gensym_alist))
		{
		  /* Vprint_gensym_alist is exposed to Lisp, so we
                     have to be careful.  */
		  CHECK_CONS (XCAR (Vprint_gensym_alist));
		  CHECK_INT (XCDR (XCAR (Vprint_gensym_alist)));
		  tem = make_int (XINT (XCDR (XCAR (Vprint_gensym_alist))) + 1);
		}
	      else
		tem = make_int (1);
	      Vprint_gensym_alist = Fcons (Fcons (obj, tem), Vprint_gensym_alist);

	      write_c_string (printcharfun, "#");
	      print_internal (tem, printcharfun, escapeflag);
	      write_c_string (printcharfun, "=");
	    }
	}
      write_c_string (printcharfun, "#:");
    }

  /* Does it look like an integer or a float? */
  {
    Ibyte *data = XSTRING_DATA (name);
    Bytecount confusing = 0;

    if (size == 0)
      goto not_yet_confused;    /* Really confusing */
    else if (isdigit (data[0]))
      confusing = 0;
    else if (size == 1)
      goto not_yet_confused;
    else if (data[0] == '-' || data[0] == '+')
      confusing = 1;
    else
      goto not_yet_confused;

    for (; confusing < size; confusing++)
      {
        if (!isdigit (data[confusing]))
          {
            confusing = 0;
            break;
          }
      }
  not_yet_confused:

    if (!confusing)
      /* #### Ugh, this is needlessly complex and slow for what we
         need here.  It might be a good idea to copy equivalent code
         from FSF.  --hniksic */
      confusing = isfloat_string ((char *) data);
    if (confusing)
      write_c_string (printcharfun, "\\");
  }

  {
    Bytecount i;
    Bytecount last = 0;

    for (i = 0; i < size; i++)
      {
	switch (string_byte (name, i))
	  {
	  case  0: case  1: case  2: case  3:
	  case  4: case  5: case  6: case  7:
	  case  8: case  9: case 10: case 11:
	  case 12: case 13: case 14: case 15:
	  case 16: case 17: case 18: case 19:
	  case 20: case 21: case 22: case 23:
	  case 24: case 25: case 26: case 27:
	  case 28: case 29: case 30: case 31:
	  case ' ': case '\"': case '\\': case '\'':
	  case ';': case '#' : case '(' : case ')':
	  case ',': case '.' : case '`' :
	  case '[': case ']' : case '?' :
	    if (i > last)
	      output_string (printcharfun, 0, name, last, i - last);
	    write_c_string (printcharfun, "\\");
	    last = i;
	  }
      }
    output_string (printcharfun, 0, name, last, size - last);
  }
  UNGCPRO;
}


/* Useful on systems or in places where writing to stdout is unavailable or
   not working. */

static int alternate_do_pointer;
static int alternate_do_size;
static char *alternate_do_string;

DEFUN ("alternate-debugging-output", Falternate_debugging_output, 1, 1, 0, /*
Append CHARACTER to the array `alternate_do_string'.
This can be used in place of `external-debugging-output' as a function
to be passed to `print'.  Before calling `print', set `alternate_do_pointer'
to 0.
*/
       (character))
{
  Ibyte str[MAX_ICHAR_LEN];
  Bytecount len;

  CHECK_CHAR_COERCE_INT (character);
  len = set_itext_ichar (str, XCHAR (character));
  write_string_to_alternate_debugging_output (str, len);
  
  return character;
}

static void
write_string_to_alternate_debugging_output (const Ibyte *str, Bytecount len)
{
  int extlen;
  const Extbyte *extptr;
#if 0 /* We want to see the internal representation, don't we? */
  if (initialized && !inhibit_non_essential_conversion_operations)
    TO_EXTERNAL_FORMAT (DATA, (str, len),
			ALLOCA, (extptr, extlen),
			Qterminal);
  else
#endif /* 0 */
    {
      extlen = len;
      extptr = (Extbyte *) str;
    }

  /* If not yet initialized, just skip it. */
  if (alternate_do_string == NULL)
    return;

  if (alternate_do_pointer + extlen >= alternate_do_size)
    {
      alternate_do_size =
	max(alternate_do_size * 2, alternate_do_pointer + extlen + 1);
      XREALLOC_ARRAY (alternate_do_string, char, alternate_do_size);
    }
  memcpy (alternate_do_string + alternate_do_pointer, extptr, extlen);
  alternate_do_pointer += extlen;
  alternate_do_string[alternate_do_pointer] = 0;
}


DEFUN ("set-device-clear-left-side", Fset_device_clear_left_side, 2, 2, 0, /*
Set whether to output a newline before the next output to a stream device.
This will happen only if the most recently-outputted character was not
a newline -- i.e. it will make sure the left side is "clear" of text.
*/
       (device, value))
{
  if (!NILP (device))
    CHECK_LIVE_DEVICE (device);
  if (NILP (device) || DEVICE_STREAM_P (XDEVICE (device)))
    /* #### This should be per-device */
    stdout_clear_before_next_output = !NILP (value);
  return Qnil;
}

DEFUN ("device-left-side-clear-p", Fdevice_left_side_clear_p, 0, 1, 0, /*
For stream devices, true if the most recent-outputted character was a newline.
*/
       (device))
{
  if (!NILP (device))
    CHECK_LIVE_DEVICE (device);
  if (NILP (device) || DEVICE_STREAM_P (XDEVICE (device)))
    /* #### This should be per-device */
    return stdout_needs_newline ? Qt : Qnil;
  return Qnil;
}

DEFUN ("external-debugging-output", Fexternal_debugging_output, 1, 3, 0, /*
Write CHAR-OR-STRING to stderr or stdout.
If optional arg STDOUT-P is non-nil, write to stdout; otherwise, write
to stderr.  You can use this function to write directly to the terminal.
This function can be used as the STREAM argument of Fprint() or the like.

Under MS Windows, this writes output to the console window (which is
created, if necessary), unless XEmacs is being run noninteractively
\(i.e. using the `-batch' argument).

If you have opened a termscript file (using `open-termscript'), then
the output also will be logged to this file.
*/
       (char_or_string, stdout_p, device))
{
  FILE *file = 0;
  struct console *con = 0;

  if (NILP (device))
    {
      if (!NILP (stdout_p))
	file = stdout;
      else
	file = stderr;
    }
  else
    {
      CHECK_LIVE_DEVICE (device);
      if (!DEVICE_TTY_P (XDEVICE (device)) &&
	  !DEVICE_STREAM_P (XDEVICE (device)))
	wtaerror ("Must be tty or stream device", device);
      con = XCONSOLE (DEVICE_CONSOLE (XDEVICE (device)));
      if (DEVICE_TTY_P (XDEVICE (device)))
	file = 0;
      else if (!NILP (stdout_p))
	file = CONSOLE_STREAM_DATA (con)->out;
      else
	file = CONSOLE_STREAM_DATA (con)->err;
    }

  if (STRINGP (char_or_string))
    write_string_to_stdio_stream (file, con,
				  XSTRING_DATA (char_or_string),
				  XSTRING_LENGTH (char_or_string),
				  print_unbuffered);
  else
    {
      Ibyte str[MAX_ICHAR_LEN];
      Bytecount len;

      CHECK_CHAR_COERCE_INT (char_or_string);
      len = set_itext_ichar (str, XCHAR (char_or_string));
      write_string_to_stdio_stream (file, con, str, len, print_unbuffered);
    }

  return char_or_string;
}

DEFUN ("open-termscript", Fopen_termscript, 1, 1, "FOpen termscript file: ", /*
Start writing all terminal output to FILENAME as well as the terminal.
FILENAME = nil means just close any termscript file currently open.
*/
       (filename))
{
  /* This function can GC */
  if (termscript != 0)
    {
      retry_fclose (termscript);
      termscript = 0;
    }

  if (! NILP (filename))
    {
      filename = Fexpand_file_name (filename, Qnil);
      termscript = qxe_fopen (XSTRING_DATA (filename), "w");
      if (termscript == NULL)
	report_file_error ("Opening termscript", filename);
    }
  return Qnil;
}

static int debug_print_length   = 50;
static int debug_print_level    = 15;
static int debug_print_readably = -1;

/* Restore values temporarily bound by debug_prin1.  We use this approach to
   avoid consing in debug_prin1.  That is verboten, since debug_prin1 can be
   called by cons debugging code. */
static Lisp_Object
debug_prin1_exit (Lisp_Object UNUSED (ignored))
{
  struct debug_bindings *bindings = 
    (struct debug_bindings *) XOPAQUE (debug_prin1_bindings)->data;
  inhibit_non_essential_conversion_operations =
    bindings->inhibit_non_essential_conversion_operations;
  print_depth = bindings->print_depth;
  print_readably = bindings->print_readably;
  print_unbuffered = bindings->print_unbuffered;
  gc_currently_forbidden = bindings->gc_currently_forbidden;
  Vprint_length = bindings->Vprint_length;
  Vprint_level = bindings->Vprint_level;
  Vinhibit_quit = bindings->Vinhibit_quit;
  return Qnil;
}

/* Print an object, `prin1'-style, to various possible debugging outputs.
   Make sure it's completely unbuffered so that, in the event of a crash
   somewhere, we see as much as possible that happened before it.
   */
static void
debug_prin1 (Lisp_Object debug_print_obj, int flags)
{
  /* This function can GC */

  /* by doing this, we trick various things that are non-essential
     but might cause crashes into not getting executed. */
  int specdepth;
  struct debug_bindings *bindings = 
    (struct debug_bindings *) XOPAQUE (debug_prin1_bindings)->data;

  bindings->inhibit_non_essential_conversion_operations =
    inhibit_non_essential_conversion_operations;
  bindings->print_depth = print_depth;
  bindings->print_readably = print_readably;
  bindings->print_unbuffered = print_unbuffered;
  bindings->gc_currently_forbidden = gc_currently_forbidden;
  bindings->Vprint_length = Vprint_length;
  bindings->Vprint_level = Vprint_level;
  bindings->Vinhibit_quit = Vinhibit_quit;
  specdepth = record_unwind_protect (debug_prin1_exit, Qnil);

  inhibit_non_essential_conversion_operations = 1;
  print_depth = 0;
  print_readably = debug_print_readably != -1 ? debug_print_readably : 0;
  print_unbuffered++;
  if (debug_print_length > 0)
    Vprint_length = make_int (debug_print_length);
  if (debug_print_level > 0)
    Vprint_level = make_int (debug_print_level);
  Vinhibit_quit = Qt;

  if ((flags & EXT_PRINT_STDOUT) || (flags & EXT_PRINT_STDERR))
    print_internal (debug_print_obj, Qexternal_debugging_output, 1);
  if (flags & EXT_PRINT_ALTERNATE)
    print_internal (debug_print_obj, Qalternate_debugging_output, 1);
#ifdef WIN32_NATIVE
  if (flags & EXT_PRINT_MSWINDOWS)
    {
      /* Write out to the debugger, as well */
      print_internal (debug_print_obj, Qmswindows_debugging_output, 1);
    }
#endif

  unbind_to (specdepth);
}

void
debug_p4 (Lisp_Object obj)
{
  inhibit_non_essential_conversion_operations = 1;
  if (STRINGP (obj))
    debug_out ("\"%s\"", XSTRING_DATA (obj));
  else if (CONSP (obj))
    {
      int first = 1;
      do {
	debug_out (first ? "(" : " ");
	first = 0;
	debug_p4 (XCAR (obj));
	obj = XCDR (obj);
      } while (CONSP (obj));
      if (NILP (obj))
	debug_out (")");
      else
	{
	  debug_out (" . ");
	  debug_p4 (obj);
	  debug_out (")");
	}
    }
  else if (VECTORP (obj))
    {
      int size = XVECTOR_LENGTH (obj);
      int i;
      int first = 1;

      for (i = 0; i < size; i++)
	{
	  debug_out (first ? "[" : " ");
	  first = 0;
	  debug_p4 (XVECTOR_DATA (obj)[i]);
	  debug_out ("]");
	}
    }
  else if (SYMBOLP (obj))
    {
      Lisp_Object name = XSYMBOL_NAME (obj);
      if (!STRINGP (name))
	debug_out ("<<bad symbol>>");
      else
	debug_out ("%s", XSTRING_DATA (name));
    }
  else if (INTP (obj))
    {
      debug_out ("%ld", XINT (obj));
    }
  else if (FLOATP (obj))
    {
      debug_out ("%g", XFLOAT_DATA (obj));
    }
  else
    {
      struct lrecord_header *header =
	(struct lrecord_header *) XPNTR (obj);

      if (header->type >= lrecord_type_last_built_in_type)
	debug_out ("<< bad object type=%d 0x%lx>>", header->type,
		   (EMACS_INT) header);
      else
#ifdef NEW_GC
	debug_out ("#<%s addr=0x%lx uid=0x%lx>",
		   LHEADER_IMPLEMENTATION (header)->name,
		   (EMACS_INT) header,
		   (EMACS_INT) ((struct lrecord_header *) header)->uid);
#else /* not NEW_GC */
	debug_out ("#<%s addr=0x%lx uid=0x%lx>",
		   LHEADER_IMPLEMENTATION (header)->name,
		   (EMACS_INT) header,
		   (EMACS_INT) (LHEADER_IMPLEMENTATION (header)->basic_p ?
				((struct lrecord_header *) header)->uid :
				((struct old_lcrecord_header *) header)->uid));
#endif /* not NEW_GC */
    }

  inhibit_non_essential_conversion_operations = 0;
}

static void
ext_print_begin (int dest)
{
  if (dest & EXT_PRINT_ALTERNATE)
    alternate_do_pointer = 0;
  if (dest & (EXT_PRINT_STDERR | EXT_PRINT_STDOUT))
    stdout_clear_before_next_output = 1;
}

static void
ext_print_end (int dest)
{
  if (dest & (EXT_PRINT_MSWINDOWS | EXT_PRINT_STDERR | EXT_PRINT_STDOUT))
    external_out (dest & (EXT_PRINT_MSWINDOWS | EXT_PRINT_STDERR |
			  EXT_PRINT_STDOUT), "\n");
}

static void
external_debug_print (Lisp_Object object, int dest)
{
  ext_print_begin (dest);
  debug_prin1 (object, dest);
  ext_print_end (dest);
}

void
debug_p3 (Lisp_Object obj)
{
  debug_p4 (obj);
  inhibit_non_essential_conversion_operations = 1;
  debug_out ("\n");
  inhibit_non_essential_conversion_operations = 0;
}

void
debug_print (Lisp_Object debug_print_obj)
{
  external_debug_print (debug_print_obj, EXT_PRINT_ALL);
}

/* Getting tired of typing debug_print() ... */
void dp (Lisp_Object debug_print_obj);
void
dp (Lisp_Object debug_print_obj)
{
  debug_print (debug_print_obj);
}

/* Alternate debug printer: Return a char * pointer to the output */
char *dpa (Lisp_Object debug_print_obj);
char *
dpa (Lisp_Object debug_print_obj)
{
  external_debug_print (debug_print_obj, EXT_PRINT_ALTERNATE);
  
  return alternate_do_string;
}

/* Debugging kludge -- unbuffered */
/* This function provided for the benefit of the debugger.  */
void
debug_backtrace (void)
{
  /* This function can GC */

  /* by doing this, we trick various things that are non-essential
     but might cause crashes into not getting executed. */
  int specdepth = 
    internal_bind_int (&inhibit_non_essential_conversion_operations, 1);

  internal_bind_int (&print_depth, 0);
  internal_bind_int (&print_readably, 0);
  internal_bind_int (&print_unbuffered, print_unbuffered + 1);
  if (debug_print_length > 0)
    internal_bind_lisp_object (&Vprint_length, make_int (debug_print_length));
  if (debug_print_level > 0)
    internal_bind_lisp_object (&Vprint_level, make_int (debug_print_level));
  /* #### Do we need this?  It was in the old code. */
  internal_bind_lisp_object (&Vinhibit_quit, Vinhibit_quit);

  Fbacktrace (Qexternal_debugging_output, Qt);
  stderr_out ("\n");

  unbind_to (specdepth);
}

/* Getting tired of typing debug_backtrace() ... */
void db (void);
void
db (void)
{
  debug_backtrace ();
}

void
debug_short_backtrace (int length)
{
  int first = 1;
  struct backtrace *bt = backtrace_list;
  debug_out ("   [");
  while (length > 0 && bt)
    {
      if (!first)
	{
	  debug_out (", ");
	}
      if (COMPILED_FUNCTIONP (*bt->function))
	{
#if defined (COMPILED_FUNCTION_ANNOTATION_HACK)
	  Lisp_Object ann =
	    compiled_function_annotation (XCOMPILED_FUNCTION (*bt->function));
#else
	  Lisp_Object ann = Qnil;
#endif
	  if (!NILP (ann))
	    {
	      debug_out ("<compiled-function from ");
	      debug_prin1 (ann, EXT_PRINT_ALL);
	      debug_out (">");
	    }
	  else
	    {
	      debug_out ("<compiled-function of unknown origin>");
	    }
	}
      else
	debug_prin1 (*bt->function, EXT_PRINT_ALL);
      first = 0;
      length--;
      bt = bt->next;
    }
  debug_out ("]\n");
}


void
syms_of_print (void)
{
  DEFSYMBOL (Qstandard_output);

  DEFSYMBOL (Qprint_length);

  DEFSYMBOL (Qprint_string_length);

  DEFSYMBOL (Qdisplay_error);
  DEFSYMBOL (Qprint_message_label);

  DEFSUBR (Fprin1);
  DEFSUBR (Fprin1_to_string);
  DEFSUBR (Fprinc);
  DEFSUBR (Fprint);
  DEFSUBR (Ferror_message_string);
  DEFSUBR (Fdisplay_error);
  DEFSUBR (Fterpri);
  DEFSUBR (Fwrite_char);
  DEFSUBR (Falternate_debugging_output);
  DEFSUBR (Fset_device_clear_left_side);
  DEFSUBR (Fdevice_left_side_clear_p);
  DEFSUBR (Fexternal_debugging_output);
  DEFSUBR (Fopen_termscript);
  DEFSYMBOL (Qexternal_debugging_output);
  DEFSYMBOL (Qalternate_debugging_output);
#ifdef HAVE_MS_WINDOWS
  DEFSYMBOL (Qmswindows_debugging_output);
#endif
  DEFSUBR (Fwith_output_to_temp_buffer);
}

void
reinit_vars_of_print (void)
{
  alternate_do_pointer = 0;
}

void
vars_of_print (void)
{
  DEFVAR_LISP ("standard-output", &Vstandard_output /*
Output stream `print' uses by default for outputting a character.
This may be any function of one argument.
It may also be a buffer (output is inserted before point)
or a marker (output is inserted and the marker is advanced)
or the symbol t (output appears in the minibuffer line).
*/ );
  Vstandard_output = Qt;

  DEFVAR_LISP ("float-output-format", &Vfloat_output_format /*
The format descriptor string that lisp uses to print floats.
This is a %-spec like those accepted by `printf' in C,
but with some restrictions.  It must start with the two characters `%.'.
After that comes an integer precision specification,
and then a letter which controls the format.
The letters allowed are `e', `f' and `g'.
Use `e' for exponential notation "DIG.DIGITSeEXPT"
Use `f' for decimal point notation "DIGITS.DIGITS".
Use `g' to choose the shorter of those two formats for the number at hand.
The precision in any of these cases is the number of digits following
the decimal point.  With `f', a precision of 0 means to omit the
decimal point.  0 is not allowed with `f' or `g'.

A value of nil means to use `%.16g'.

Regardless of the value of `float-output-format', a floating point number
will never be printed in such a way that it is ambiguous with an integer;
that is, a floating-point number will always be printed with a decimal
point and/or an exponent, even if the digits following the decimal point
are all zero.  This is to preserve read-equivalence.
*/ );
  Vfloat_output_format = Qnil;

  DEFVAR_LISP ("print-length", &Vprint_length /*
Maximum length of list or vector to print before abbreviating.
A value of nil means no limit.
*/ );
  Vprint_length = Qnil;

  DEFVAR_LISP ("print-string-length", &Vprint_string_length /*
Maximum length of string to print before abbreviating.
A value of nil means no limit.
*/ );
  Vprint_string_length = Qnil;

  DEFVAR_LISP ("print-level", &Vprint_level /*
Maximum depth of list nesting to print before abbreviating.
A value of nil means no limit.
*/ );
  Vprint_level = Qnil;

  DEFVAR_BOOL ("print-escape-newlines", &print_escape_newlines /*
Non-nil means print newlines in strings as backslash-n.
*/ );
  print_escape_newlines = 0;

  DEFVAR_BOOL ("print-readably", &print_readably /*
If non-nil, then all objects will be printed in a readable form.
If an object has no readable representation, then an error is signalled.
When print-readably is true, compiled-function objects will be written in
 #[...] form instead of in #<compiled-function [...]> form, and two-element
 lists of the form (quote object) will be written as the equivalent 'object.
Do not SET this variable; bind it instead.
*/ );
  print_readably = 0;

  /* #### I think this should default to t.  But we'd better wait
     until we see that it works out.  */
  DEFVAR_LISP ("print-gensym", &Vprint_gensym /*
If non-nil, then uninterned symbols will be printed specially.
Uninterned symbols are those which are not present in `obarray', that is,
those which were made with `make-symbol' or by calling `intern' with a
second argument.

When print-gensym is true, such symbols will be preceded by "#:",
which causes the reader to create a new symbol instead of interning
and returning an existing one.  Beware: the #: syntax creates a new
symbol each time it is seen, so if you print an object which contains
two pointers to the same uninterned symbol, `read' will not duplicate
that structure.

If the value of `print-gensym' is a cons cell, then in addition
refrain from clearing `print-gensym-alist' on entry to and exit from
printing functions, so that the use of #...# and #...= can carry over
for several separately printed objects.
*/ );
  Vprint_gensym = Qnil;

  DEFVAR_LISP ("print-gensym-alist", &Vprint_gensym_alist /*
Association list of elements (GENSYM . N) to guide use of #N# and #N=.
In each element, GENSYM is an uninterned symbol that has been associated
with #N= for the specified value of N.
*/ );
  Vprint_gensym_alist = Qnil;

  DEFVAR_LISP ("print-message-label", &Vprint_message_label /*
Label for minibuffer messages created with `print'.  This should
generally be bound with `let' rather than set.  (See `display-message'.)
*/ );
  Vprint_message_label = Qprint;

  debug_prin1_bindings =
    make_opaque (OPAQUE_UNINIT, sizeof (struct debug_bindings));
  staticpro (&debug_prin1_bindings);

  alternate_do_size = 5000;
  alternate_do_string = xnew_array(char, 5000);
}