/* Call a Lisp function interactively.
   Copyright (C) 1985, 1986, 1992, 1993, 1994 Free Software Foundation, Inc.
   Copyright (C) 1995, 1996, 2001, 2002 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 3 of the License, 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.  If not, see <http://www.gnu.org/licenses/>. */

/* Synched up with: FSF 19.30, Mule 2.0. */

/* Authorship:

   FSF: long ago.
   Mly or JWZ: various changes.
 */

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

#include "buffer.h"
#include "bytecode.h"
#include "commands.h"
#include "events.h"
#include "insdel.h"
#include "window-impl.h" /* WINDOW_MINI_P */

extern Charcount num_input_chars;

Lisp_Object Vcurrent_prefix_arg;
Lisp_Object Qcall_interactively;
Lisp_Object Vcommand_history;

Lisp_Object Vcommand_debug_status, Qcommand_debug_status;
Lisp_Object Qenable_recursive_minibuffers;

#if 0 /* FSFmacs */
/* Non-nil means treat the mark as active
   even if mark_active is 0.  */
Lisp_Object Vmark_even_if_inactive;
#endif

#if 0 /* ill-conceived */
/* FSF calls Qmouse_leave_buffer_hook at all sorts of random places,
   including a bunch of places in their mouse.el.  If this is
   implemented, it has to be done cleanly. */
Lisp_Object Vmouse_leave_buffer_hook, Qmouse_leave_buffer_hook;
#endif

Lisp_Object QletX, Qsave_excursion;

Lisp_Object Qread_from_minibuffer;
Lisp_Object Qread_file_name;
Lisp_Object Qread_directory_name;
Lisp_Object Qcompleting_read;
Lisp_Object Qread_buffer;
Lisp_Object Qread_function;
Lisp_Object Qread_variable;
Lisp_Object Qread_expression;
Lisp_Object Qread_command;
Lisp_Object Qread_number;
Lisp_Object Qread_string;
Lisp_Object Qevents_to_keys;

Lisp_Object Qread_coding_system;
Lisp_Object Qread_non_nil_coding_system;

/* ARGSUSED */
DEFUN ("interactive", Finteractive, 0, UNEVALLED, 0, /*
Specify a way of parsing arguments for interactive use of a function.
For example, write
  (defun foo (arg) "Doc string" (interactive "p") ...use arg...)
to make ARG be the prefix argument when `foo' is called as a command.
The "call" to `interactive' is actually a declaration rather than a function;
 it tells `call-interactively' how to read arguments
 to pass to the function.
The interactive form must appear at the top level of the function body.  If
 it is wrapped in a `let' or `progn' or similar, Lisp will not even realize
 the function is an interactive command!
When actually called, `interactive' just returns nil.

The argument of `interactive' is usually a string containing a code letter
 followed by a prompt.  (Some code letters do not use I/O to get
 the argument and do not need prompts.)  To prompt for multiple arguments,
 give a code letter, its prompt, a newline, and another code letter, etc.
 Prompts are passed to format, and may use % escapes to print the
 arguments that have already been read.
If the argument is not a string, it is evaluated to get a list of
 arguments to pass to the function.
Just `(interactive)' means pass no args when calling interactively.

Code letters available are:
a -- Function name: symbol with a function definition.
b -- Name of existing buffer.
B -- Name of buffer, possibly nonexistent.
c -- Character.
C -- Command name: symbol with interactive function definition.
d -- Value of point as number.  Does not do I/O.
D -- Directory name.
e -- Last mouse-button or misc-user event that invoked this command.
     If used more than once, the Nth `e' returns the Nth such event.
     Does not do I/O.
f -- Existing file name.
F -- Possibly nonexistent file name.
i -- Always nil, ignore.  Use to skip arguments when interactive.
k -- Key sequence (a vector of events).
K -- Key sequence to be redefined (do not automatically down-case).
m -- Value of mark as number.  Does not do I/O.
n -- Number read using minibuffer.
N -- Prefix arg converted to number, or if none, do like code `n'.
p -- Prefix arg converted to number.  Does not do I/O.
P -- Prefix arg in raw form.  Does not do I/O.
r -- Region: point and mark as 2 numeric args, smallest first.  Does no I/O.
s -- Any string.
S -- Any symbol.
v -- Variable name: symbol that is user-variable-p.
x -- Lisp expression read but not evaluated.
X -- Lisp expression read and evaluated.
z -- Coding system. (Always nil if no Mule support.)
Z -- Coding system, nil if no prefix arg. (Always nil if no Mule support.)
In addition, if the string begins with `*'
 then an error is signaled if the buffer is read-only.
 This happens before reading any arguments.
If the string begins with `@', then the window the mouse is over is selected
 before anything else is done.
If the string begins with `_', then this command will not cause the region
 to be deactivated when it completes; that is, `zmacs-region-stays' will be
 set to t when the command exits successfully.
You may use any of `@', `*' and `_' at the beginning of the string;
 they are processed in the order that they appear.


When writing your own interactive spec, it can be useful to know the
equivalent Lisp expressions for the various code letters.  They are:

a -- (read-function "PROMPT")
b -- (let ((def (current-buffer)))
       (if (eq (selected-window) (active-minibuffer-window))
           (setq def (other-buffer def))
       (read-buffer "PROMPT" def t)))
B -- (read-buffer "PROMPT" (other-buffer (current-buffer)))
c -- (prog1
         (let ((cursor-in-echo-area t))
           (message "%s" "PROMPT")
           (read-char))
       (message nil))
C -- (read-command "PROMPT")
d -- (point)
D -- (read-directory-name "PROMPT" nil default-directory t)
e -- current-mouse-event ;; #### not quite right. needs access to the KEYS
                         ;; argument of `call-interactively', but that's
                         ;; currently impossible.
f -- (read-file-name "PROMPT" nil nil 0)
F -- (read-file-name "PROMPT")
i -- nil
k -- (read-key-sequence "PROMPT")
K -- (read-key-sequence "PROMPT" nil t)
m -- (mark)
n -- (read-number "PROMPT")
N -- (if current-prefix-arg
         (prefix-numeric-value current-prefix-arg)
       (read-number "PROMPT"))
p -- (prefix-numeric-value current-prefix-arg)
P -- current-prefix-arg
r -- (if (and zmacs-regions (not zmacs-region-active-p))
         (error "The region is not active now"))
     (let ((tem (marker-buffer (mark-marker t))))
       (unless (and tem (eq tem (current-buffer)))
         (error "The mark is now set now")))
     (region-beginning) +
     (region-end)
s -- (read-string "PROMPT")
S -- (let (tem prev-tem)
       (while (not tem)
         (setq tem (completing-read "PROMPT" obarray nil nil prev-tem))
         (setq prev-tem tem)
         (setq tem (intern tem))
         (if (= (length tem) 0)
             (setq tem nil))))
v -- (read-variable "PROMPT")
x -- (read-expression "PROMPT")
X -- (eval (read-expression "PROMPT"))
z -- (and (fboundp 'read-coding-system) (read-coding-system "PROMPT"))
Z -- (and current-prefix-arg (fboundp 'read-coding-system)
       (read-coding-system "PROMPT"))

`*' (barf-if-buffer-read-only)
`@' (let ((event current-mouse-event)) ;; #### not quite right; needs the
      (when event                      ;; value from the `e' spec above.
        (let ((window event-window event))
          (when window
            (if (and (window-minibuffer-p window)
                     (not (and (> (minibuffer-depth) 0)
                               (eq window (active-minibuffer-window)))))
              (error "Attempt to select inactive minibuffer window"))
            (select window)))))
`_' (setq zmacs-region-stays t) *//* FIXME: moving end of previous comment
to a separate line causes docstring lossage! */
       (UNUSED (args)))
{
  return Qnil;
}

/* Modify EXPR by quotifying each element (except the first).  */
static Lisp_Object
quotify_args (Lisp_Object expr)
{
  EXTERNAL_LIST_LOOP_3 (elt, expr, tail)
    XSETCAR (tail, Fquote_maybe (elt));
  return expr;
}

static Charbpos
check_mark (void)
{
  Lisp_Object tem;

  if (zmacs_regions && !zmacs_region_active_p)
    invalid_operation ("The region is not active now", Qunbound);

  tem = Fmarker_buffer (current_buffer->mark);
  if (NILP (tem) || (XBUFFER (tem) != current_buffer))
    invalid_operation ("The mark is not set now", Qunbound);

  return marker_position (current_buffer->mark);
}

static Lisp_Object
callint_prompt (const Ibyte *prompt_start, Bytecount prompt_length,
                const Lisp_Object *args, int nargs)
{
  Lisp_Object s = make_string (prompt_start, prompt_length);
  struct gcpro gcpro1;

  /* Fformat no longer smashes its arg vector, so no need to copy it. */

  if (!strchr ((char *) XSTRING_DATA (s), '%'))
    return s;
  GCPRO1 (s);
  RETURN_UNGCPRO (emacs_vsprintf_string_lisp (0, s, nargs, args));
}

/* `lambda' for RECORD-FLAG is an XEmacs addition. */

DEFUN ("call-interactively", Fcall_interactively, 1, 3, 0, /*
Call FUNCTION, reading args according to its interactive calling specs.
Return the value FUNCTION returns.
The function contains a specification of how to do the argument reading.
In the case of user-defined functions, this is specified by placing a call
to the function `interactive' at the top level of the function body.
See `interactive'.

If optional second arg RECORD-FLAG is the symbol `lambda', the interactive
calling arguments for FUNCTION are read and returned as a list,
but the function is not called on them.

If RECORD-FLAG is `t' then unconditionally put this command in the
command-history.  Otherwise, this is done only if an arg is read using
the minibuffer.

The argument KEYS specifies the value to use instead of (this-command-keys)
when reading the arguments.
*/
       (function, record_flag, keys))
{
  /* This function can GC */
  int speccount = specpdl_depth ();
  Lisp_Object prefix;

  Lisp_Object fun;
  Lisp_Object specs = Qnil;
#ifdef IT_SEEMS_THAT_MLY_DOESNT_LIKE_THIS
  Lisp_Object enable;
#endif
  /* If SPECS is a string, we reset prompt_data to XSTRING_DATA (specs)
     every time a GC might have occurred */
  const char *prompt_data = 0;
  int prompt_index = 0;
  int argcount;
  int set_zmacs_region_stays = 0;
  int mouse_event_count = 0;

  if (!NILP (keys))
    {
      int i, len;

      CHECK_VECTOR (keys);
      len = XVECTOR_LENGTH (keys);
      for (i = 0; i < len; i++)
	CHECK_LIVE_EVENT (XVECTOR_DATA (keys)[i]);
    }

  /* Save this now, since use of minibuffer will clobber it. */
  prefix = Vcurrent_prefix_arg;

 retry:

#ifdef IT_SEEMS_THAT_MLY_DOESNT_LIKE_THIS
  /* Marginal kludge.  Use an evaluated interactive spec instead of this! */
  if (SYMBOLP (function))
    enable = Fget (function, Qenable_recursive_minibuffers, Qnil);
#endif

  fun = indirect_function (function, 1);

  /* Decode the kind of function.  Either handle it and return,
     or go to `lose' if not interactive, or go to `retry'
     to specify a different function, or set either PROMPT_DATA or SPECS. */

  if (SUBRP (fun))
    {
      prompt_data = XSUBR (fun)->prompt;
      if (!prompt_data)
	{
	lose:
	  function = wrong_type_argument (Qcommandp, function);
	  goto retry;
	}
#if 0 /* FSFmacs */ /* Huh? Where is this used? */
      if ((EMACS_INT) prompt_data == 1)
	/* Let SPECS (which is nil) be used as the args.  */
	prompt_data = 0;
#endif
    }
  else if (COMPILED_FUNCTIONP (fun))
    {
      Lisp_Compiled_Function *f = XCOMPILED_FUNCTION (fun);
      if (! f->flags.interactivep)
        goto lose;
      specs = compiled_function_interactive (f);
    }
  else if (!CONSP (fun))
    goto lose;
  else
    {
      Lisp_Object funcar = Fcar (fun);

      if (EQ (funcar, Qautoload))
	{
	  struct gcpro gcpro1;
	  GCPRO1 (prefix);
	  /* do_autoload GCPROs both arguments */
	  do_autoload (fun, function);
	  UNGCPRO;
	  goto retry;
	}
      else if (EQ (funcar, Qlambda))
	{
	  specs = Fassq (Qinteractive, Fcdr (Fcdr (fun)));
	  if (NILP (specs))
	    goto lose;
	  specs = Fcar (Fcdr (specs));
	}
      else
	goto lose;
    }

  /* FSFmacs makes an ALLOCA() copy of prompt_data here.
     We're more intelligent about this and just reset prompt_data
     as necessary. */
  /* If either specs or prompt_data is set to a string, use it.  */
  if (!STRINGP (specs) && prompt_data == 0)
    {
      struct gcpro gcpro1, gcpro2, gcpro3;
      int i = num_input_chars;
      Lisp_Object input = specs;

      GCPRO3 (function, specs, input);
      /* Compute the arg values using the user's expression.  */
      specs = IGNORE_MULTIPLE_VALUES (Feval (specs));
      if (EQ (record_flag, Qlambda)) /* XEmacs addition */
	{
	  UNGCPRO;
	  return specs;
	}
      if (!NILP (record_flag) || i != num_input_chars)
	{
	  /* We should record this command on the command history.  */
	  /* #### The following is too specific; should have general
	     mechanism for doing this. */
	  Lisp_Object values, car;
	  /* Make a copy of the list of values, for the command history,
	     and turn them into things we can eval.  */
	  values = quotify_args (Fcopy_sequence (specs));
	  /* If the list of args was produced with an explicit call to `list',
	     look for elements that were computed with (region-beginning)
	     or (region-end), and put those expressions into VALUES
	     instead of the present values.  */
	  if (CONSP (input))
	    {
	      car = XCAR (input);
	      /* Skip through certain special forms.  */
	      while (EQ (car, Qlet) || EQ (car, QletX)
		     || EQ (car, Qsave_excursion))
		{
		  while (CONSP (XCDR (input)))
		    input = XCDR (input);
		  input = XCAR (input);
		  if (!CONSP (input))
		    break;
		  car = XCAR (input);
		}
	      if (EQ (car, Qlist))
		{
		  Lisp_Object intail, valtail;
		  for (intail = Fcdr (input), valtail = values;
		       CONSP (valtail);
		       intail = Fcdr (intail), valtail = Fcdr (valtail))
		    {
		      Lisp_Object elt;
		      elt = Fcar (intail);
		      if (CONSP (elt))
			{
			  Lisp_Object eltcar = Fcar (elt);
			  if (EQ (eltcar, Qpoint) ||
			      EQ (eltcar, Qmark)  ||
			      EQ (eltcar, Qregion_beginning) ||
			      EQ (eltcar, Qregion_end))
			    Fsetcar (valtail, Fcar (intail));
			}
		    }
		}
	    }
	  Vcommand_history
	    = Fcons (Fcons (function, values), Vcommand_history);
	}
      single_console_state ();
      RETURN_UNGCPRO (apply1 (fun, specs));
    }

  /* Here if function specifies a string to control parsing the defaults */

#ifdef I18N3
  /* Translate interactive prompt. */
  if (STRINGP (specs))
    {
      Lisp_Object domain = Qnil;
      if (COMPILED_FUNCTIONP (fun))
	domain = compiled_function_domain (XCOMPILED_FUNCTION (fun));
      if (NILP (domain))
	specs = Fgettext (specs);
      else
	specs = Fdgettext (domain, specs);
    }
  else if (prompt_data)
    /* We do not have to worry about domains in this case because
       prompt_data is non-nil only for built-in functions, which
       always use the default domain. */
    prompt_data = gettext (prompt_data);
#endif

  /* Handle special starting chars `*' and `@' and `_'.  */
  /* Note that `+' is reserved for user extensions.  */
  prompt_index = 0;
  {
    struct gcpro gcpro1, gcpro2;
    GCPRO2 (function, specs);

    for (;;)
      {
	if (STRINGP (specs))
	  prompt_data = (const char *) XSTRING_DATA (specs);

	if (prompt_data[prompt_index] == '+')
	  syntax_error ("`+' is not used in `interactive' for ordinary commands", Qunbound);
	else if (prompt_data[prompt_index] == '*')
	  {
	    prompt_index++;
	    if (!NILP (current_buffer->read_only))
	      barf_if_buffer_read_only (current_buffer, -1, -1);
	  }
	else if (prompt_data[prompt_index] == '@')
	  {
	    Lisp_Object event;
	    prompt_index++;

	    if (!NILP (keys))
	      event = extract_vector_nth_mouse_event (keys, 0);
	    else
#if 0
	      event = extract_this_command_keys_nth_mouse_event (0);
#else
	      /* Doesn't work; see below */
	      event = Vcurrent_mouse_event;
#endif
	    if (! NILP (event))
	      {
		Lisp_Object window = Fevent_window (event);
		if (!NILP (window))
		  {
		    if (MINI_WINDOW_P (XWINDOW (window))
			&& ! (minibuf_level > 0 && EQ (window,
						       minibuf_window)))
		      invalid_operation ("Attempt to select inactive minibuffer window", Qunbound);

#if 0 /* unclean! see event-stream.c */
		    /* If the current buffer wants to clean up, let it.  */
		    if (!NILP (Vmouse_leave_buffer_hook))
		      run_hook (Qmouse_leave_buffer_hook);
#endif

		    Fselect_window (window, Qnil);
		  }
	      }
	  }
	else if (prompt_data[prompt_index] == '_')
	  {
	    prompt_index++;
	    set_zmacs_region_stays = 1;
	  }
	else
	  {
	    UNGCPRO;
	    break;
	  }
      }
  }

  /* Count the number of arguments the interactive spec would have
     us give to the function.  */
  argcount = 0;
  {
    const char *tem;
    for (tem = prompt_data + prompt_index; *tem; )
      {
	/* 'r' specifications ("point and mark as 2 numeric args")
	   produce *two* arguments.  */
	if (*tem == 'r')
	  argcount += 2;
	else
	  argcount += 1;
	tem = (const char *) strchr (tem + 1, '\n');
	if (!tem)
	  break;
	tem++;
      }
  }

#ifdef IT_SEEMS_THAT_MLY_DOESNT_LIKE_THIS
  if (!NILP (enable))
    specbind (Qenable_recursive_minibuffers, Qt);
#endif

  if (argcount == 0)
    {
      /* Interactive function or no arguments; just call it */
      if (EQ (record_flag, Qlambda))
	return Qnil;
      if (!NILP (record_flag))
	{
	  Vcommand_history = Fcons (list1 (function), Vcommand_history);
	}
      specbind (Qcommand_debug_status, Qnil);
      /* XEmacs: was fun = call0 (fun), but that's backtraced wrong */
      {
	struct gcpro gcpro1;

	GCPRO1 (fun);
	fun = Ffuncall (1, &fun);
	UNGCPRO;
      }
      if (set_zmacs_region_stays)
	zmacs_region_stays = 1;
      return unbind_to_1 (speccount, fun);
    }

  /* Read interactive arguments */
  {
    /* args[-1] is the function to call */
    /* args[n] is the n'th argument to the function */
    int alloca_size = (1	/* function to call */
                       + argcount /* actual arguments */
                       + argcount /* visargs */
                       + argcount /* varies */
                       );
    Lisp_Object *args = alloca_array (Lisp_Object, alloca_size) + 1;
    /* visargs is an array of either Qnil or user-friendlier versions (often
     *  strings) of previous arguments, to use in prompts for successive
     *  arguments.  ("Often strings" because emacs didn't used to have
     *  format %S and prin1-to-string.) */
    Lisp_Object *visargs = args + argcount;
    /* If varies[i] is non-null, the i'th argument shouldn't just have
       its value in this call quoted in the command history.  It should be
       recorded as a call to the function named varies[i]]. */
    Lisp_Object *varies = visargs + argcount;
    int arg_from_tty = 0;
    REGISTER int argnum;
    struct gcpro gcpro1, gcpro2;

    args[-1] = function;
    for (argnum = 0; argnum < alloca_size - 1; argnum++)
      args[argnum] = Qnil;

    /* Must GC-protect args[-1] (ie function) because Ffuncall doesn't */
    /* `function' itself isn't GC-protected -- use args[-1] from here
       (actually, doesn't matter since Emacs GC doesn't relocate, sigh) */
    GCPRO2 (prefix, args[-1]);
    gcpro2.nvars = alloca_size;

    for (argnum = 0; ; argnum++)
      {
	const char *prompt_start = prompt_data + prompt_index + 1;
	const char *prompt_limit = (const char *) strchr (prompt_start, '\n');
	int prompt_length;
	prompt_length = ((prompt_limit)
			 ? (prompt_limit - prompt_start)
			 : (int) strlen (prompt_start));
	if (prompt_limit && prompt_limit[1] == 0)
	  {
	    prompt_limit = 0;	/* "sfoo:\n" -- strip tailing return */
	    prompt_length -= 1;
	  }
	/* This uses `visargs' instead of `args' so that global-set-key
	   prompts with "Set key C-x C-f to command: "instead of printing
	   event objects in there.
	 */
#define PROMPT() callint_prompt ((const Ibyte *) prompt_start, prompt_length, visargs, argnum)
	switch (prompt_data[prompt_index])
	  {
	  case 'a':		/* Symbol defined as a function */
	    {
	      Lisp_Object tem = call1 (Qread_function, PROMPT ());
	      args[argnum] = tem;
	      arg_from_tty = 1;
	      break;
	    }
	  case 'b':   		/* Name of existing buffer */
	    {
	      Lisp_Object def = Fcurrent_buffer ();
	      if (EQ (Fselected_window (Qnil), minibuf_window))
		def = Fother_buffer (def, Qnil, Qnil);
              /* read-buffer returns a buffer name, not a buffer! */
	      args[argnum] = call3 (Qread_buffer, PROMPT (), def,
				    Qt);
	      arg_from_tty = 1;
	      break;
	    }
	  case 'B':		/* Name of buffer, possibly nonexistent */
	    {
              /* read-buffer returns a buffer name, not a buffer! */
	      args[argnum] = call2 (Qread_buffer, PROMPT (),
				    Fother_buffer (Fcurrent_buffer (), Qnil,
						   Qnil));
	      arg_from_tty = 1;
	      break;
	    }
	  case 'c':		/* Character */
	    {
              Lisp_Object tem;
	      int shadowing_speccount = specpdl_depth ();

	      specbind (Qcursor_in_echo_area, Qt);
	      message ("%s", XSTRING_DATA (PROMPT ()));
	      tem = (call0 (Qread_char));
              args[argnum] = tem;
              /* visargs[argnum] = Fsingle_key_description (tem); */
	      /* FSF has visargs[argnum] = Fchar_to_string (tem); */

	      unbind_to (shadowing_speccount);

	      /* #### `C-x / a' should not leave the prompt in the minibuffer.
		 This isn't the right fix, because (message ...) (read-char)
		 shouldn't leave the message there either... */
	      clear_message ();

	      arg_from_tty = 1;
	      break;
	    }
	  case 'C':		/* Command: symbol with interactive function */
	    {
	      Lisp_Object tem = call1 (Qread_command, PROMPT ());
	      args[argnum] = tem;
	      arg_from_tty = 1;
	      break;
	    }
	  case 'd':		/* Value of point.  Does not do I/O.  */
	    {
	      args[argnum] = Fcopy_marker (current_buffer->point_marker, Qt);
	      varies[argnum] = Qpoint;
	      break;
	    }
	  case 'e':
	    {
	      Lisp_Object event;

	      if (!NILP (keys))
		event = extract_vector_nth_mouse_event (keys,
							mouse_event_count);
	      else
#if 0
	      /* This doesn't quite work because this-command-keys
		 behaves in utterly counterintuitive ways.  Sometimes
		 it retrieves an event back in the future, e.g. when
		 one command invokes another command and both are
		 invoked with the mouse. */
		event = (extract_this_command_keys_nth_mouse_event
			 (mouse_event_count));
#else
	        event = Vcurrent_mouse_event;
#endif

	      if (NILP (event))
		signal_error (Qinvalid_operation,
			      "function must be bound to a mouse or misc-user event",
			      function);
	      args[argnum] = event;
	      mouse_event_count++;
	      break;
	    }
	  case 'D':		/* Directory name. */
	    {
	      args[argnum] = call4 (Qread_directory_name, PROMPT (),
				    Qnil, /* dir */
				    current_buffer->directory, /* default */
				    Qt /* must-match */
				    );
	      arg_from_tty = 1;
	      break;
	    }
	  case 'f':		/* Existing file name. */
	    {
	      Lisp_Object tem = call4 (Qread_file_name, PROMPT (),
				       Qnil, /* dir */
				       Qnil, /* default */
				       Qzero /* must-match */
				       );
              args[argnum] = tem;
	      arg_from_tty = 1;
	      break;
	    }
	  case 'F':		/* Possibly nonexistent file name. */
	    {
	      args[argnum] = call4 (Qread_file_name, PROMPT (),
				    Qnil, /* dir */
				    Qnil, /* default */
				    Qnil /* must-match */
				    );
	      arg_from_tty = 1;
	      break;
	    }
	  case 'i':		/* Ignore: always nil. Use to skip arguments. */
            {
              args[argnum] = Qnil;
              break;
            }
	  case 'k':		/* Key sequence (vector of events) */
	    {
	      struct gcpro ngcpro1;
	      Lisp_Object tem;
	      Lisp_Object key_prompt = PROMPT ();

	      NGCPRO1(key_prompt);
	      tem = Fread_key_sequence (key_prompt, Qnil, Qnil);
	      NUNGCPRO;

	      visargs[argnum] = Fkey_description (tem);
	      /* The following makes `describe-key' not work with
		 extent-local keymaps and such; and anyway, it's
		 contrary to the documentation. */
	      /* args[argnum] = call1 (Qevents_to_keys, tem); */
	      args[argnum] = tem;
	      arg_from_tty = 1;
	      break;
	    }
	  case 'K':		/* Key sequence (vector of events),
				   no automatic downcasing */
	    {
	      struct gcpro ngcpro1;
	      Lisp_Object tem;
	      Lisp_Object key_prompt = PROMPT ();

	      NGCPRO1(key_prompt);
	      tem = Fread_key_sequence (key_prompt, Qnil, Qt);
	      NUNGCPRO;

	      visargs[argnum] = Fkey_description (tem);
	      /* The following makes `describe-key' not work with
		 extent-local keymaps and such; and anyway, it's
		 contrary to the documentation. */
	      /* args[argnum] = call1 (Qevents_to_keys, tem); */
	      args[argnum] = tem;
	      arg_from_tty = 1;
	      break;
	    }

	  case 'm':		/* Value of mark.  Does not do I/O.  */
	    {
	      args[argnum] = current_buffer->mark;
	      varies[argnum] = Qmark;
	      break;
	    }
	  case 'n':		/* Read number from minibuffer.  */
	    {
	    read_number:
	      args[argnum] = call2 (Qread_number, PROMPT (), Qnil);
	      /* numbers are too boring to go on command history */
	      /* arg_from_tty = 1; */
              break;
            }
	  case 'N':		/* Prefix arg, else number from minibuffer */
	    {
	      if (NILP (prefix))
		goto read_number;
              else
                goto prefix_value;
	    }
	  case 'P':		/* Prefix arg in raw form.  Does no I/O.  */
	    {
	      args[argnum] = prefix;
	      break;
	    }
	  case 'p':		/* Prefix arg converted to number.  No I/O. */
            {
            prefix_value:
              {
                Lisp_Object tem = Fprefix_numeric_value (prefix);
                args[argnum] = tem;
              }
              break;
            }
	  case 'r':		/* Region, point and mark as 2 args. */
	    {
	      Charbpos tem = check_mark ();
	      args[argnum] = (BUF_PT (current_buffer) < tem
			      ? Fcopy_marker (current_buffer->point_marker, Qt)
			      : current_buffer->mark);
	      varies[argnum] = Qregion_beginning;
	      args[++argnum] = (BUF_PT (current_buffer) > tem
				? Fcopy_marker (current_buffer->point_marker,
						Qt)
				: current_buffer->mark);
	      varies[argnum] = Qregion_end;
	      break;
	    }
	  case 's':		/* String read via minibuffer.  */
	    {
	      args[argnum] = call1 (Qread_string, PROMPT ());
	      arg_from_tty = 1;
	      break;
	    }
	  case 'S':		/* Any symbol.  */
	    {
	      visargs[argnum] = Qnil;
	      for (;;)
		{
		  Lisp_Object tem = call5 (Qcompleting_read,
					   PROMPT (),
					   Vobarray,
					   Qnil,
					   Qnil,
					   /* nil, or prev attempt */
					   visargs[argnum]);
		  visargs[argnum] = tem;
		  /* I could use condition-case with this loser, but why bother?
		   * tem = Fread (tem); check-symbol-p;
		   */
		  tem = Fintern (tem, Qnil);
		  args[argnum] = tem;
		  if (XSTRING_LENGTH (XSYMBOL (tem)->name) > 0)
		    /* Don't accept the empty-named symbol.  If the loser
		       really wants this s/he can call completing-read
                       directly */
		    break;
		}
	      arg_from_tty = 1;
	      break;
	    }
	  case 'v':		/* Variable name: user-variable-p symbol */
	    {
	      Lisp_Object tem = call1 (Qread_variable, PROMPT ());
	      args[argnum] = tem;
	      arg_from_tty = 1;
	      break;
	    }
	  case 'x':		/* Lisp expression read but not evaluated */
	    {
	      args[argnum] = call1 (Qread_expression, PROMPT ());
              /* visargs[argnum] = Fprin1_to_string (args[argnum], Qnil); */
	      arg_from_tty = 1;
	      break;
	    }
	  case 'X':		/* Lisp expression read and evaluated */
	    {
	      Lisp_Object tem = call1 (Qread_expression, PROMPT ());
	      /* visargs[argnum] = Fprin1_to_string (tem, Qnil); */
              args[argnum] = IGNORE_MULTIPLE_VALUES (Feval (tem));
	      arg_from_tty = 1;
	      break;
	    }
	  case 'Z':		/* Coding-system symbol or nil if no prefix */
	    {
	      if (NILP (prefix))
		{
		  args[argnum] = Qnil;
		}
	      else
		{
		  args[argnum] =
		    call1 (Qread_non_nil_coding_system, PROMPT ());
		  arg_from_tty = 1;
		}
	      break;
	    }
	  case 'z':		/* Coding-system symbol */
	    {
	      args[argnum] = call1 (Qread_coding_system, PROMPT ());
	      arg_from_tty = 1;
	      break;
	    }

	    /* We have a case for `+' so we get an error
	       if anyone tries to define one here.  */
	  case '+':
	  default:
	    {
	      signal_ferror
		(Qsyntax_error,
		 "Invalid `interactive' control letter \"%c\" (#o%03o).",
		 prompt_data[prompt_index], prompt_data[prompt_index]);
	    }
	  }
#undef PROMPT
	if (NILP (visargs[argnum]))
	  visargs[argnum] = args[argnum];

	if (!prompt_limit)
	  break;
	if (STRINGP (specs))
	  prompt_data = (const char *) XSTRING_DATA (specs);
	prompt_index += prompt_length + 1 + 1; /* +1 to skip spec, +1 for \n */
      }
    unbind_to (speccount);

    QUIT;

    if (EQ (record_flag, Qlambda))
      {
	RETURN_UNGCPRO (Flist (argcount, args));
      }

    if (arg_from_tty || !NILP (record_flag))
      {
        /* Reuse visargs as a temporary for constructing the command history */
	for (argnum = 0; argnum < argcount; argnum++)
	  {
	    if (!NILP (varies[argnum]))
	      visargs[argnum] = list1 (varies[argnum]);
	    else
	      visargs[argnum] = Fquote_maybe (args[argnum]);
	  }
	Vcommand_history = Fcons (Fcons (args[-1], Flist (argcount, visargs)),
				  Vcommand_history);
      }

    /* If we used a marker to hold point, mark, or an end of the region,
       temporarily, convert it to an integer now.  */
    for (argnum = 0; argnum < argcount; argnum++)
      if (!NILP (varies[argnum]))
	args[argnum] = make_fixnum (marker_position (args[argnum]));

    single_console_state ();
    specbind (Qcommand_debug_status, Qnil);
    fun = Ffuncall (argcount + 1, args - 1);
    UNGCPRO;
    if (set_zmacs_region_stays)
      zmacs_region_stays = 1;
    return unbind_to_1 (speccount, fun);
  }
}

DEFUN ("prefix-numeric-value", Fprefix_numeric_value, 1, 1, 0, /*
Return numeric meaning of raw prefix argument RAW.
A raw prefix argument is what you get from `(interactive "P")'.
Its numeric meaning is what you would get from `(interactive "p")'.
*/
       (raw))
{
  if (NILP (raw))
    return make_fixnum (1);
  if (EQ (raw, Qminus))
    return make_fixnum (-1);
  if (FIXNUMP (raw))
    return raw;
  if (CONSP (raw) && FIXNUMP (XCAR (raw)))
    return XCAR (raw);

  return make_fixnum (1);
}

void
syms_of_callint (void)
{
  DEFSYMBOL (Qcall_interactively);
  DEFSYMBOL (Qread_from_minibuffer);
  DEFSYMBOL (Qcompleting_read);
  DEFSYMBOL (Qread_file_name);
  DEFSYMBOL (Qread_directory_name);
  DEFSYMBOL (Qread_string);
  DEFSYMBOL (Qread_buffer);
  DEFSYMBOL (Qread_variable);
  DEFSYMBOL (Qread_function);
  DEFSYMBOL (Qread_command);
  DEFSYMBOL (Qread_number);
  DEFSYMBOL (Qread_expression);
  DEFSYMBOL (Qread_coding_system);
  DEFSYMBOL (Qread_non_nil_coding_system);
  DEFSYMBOL (Qevents_to_keys);
  DEFSYMBOL (Qcommand_debug_status);
  DEFSYMBOL (Qenable_recursive_minibuffers);

  defsymbol (&QletX, "let*");
  DEFSYMBOL (Qsave_excursion);
#if 0 /* ill-conceived */
  DEFSYMBOL (Qmouse_leave_buffer_hook);
#endif

  DEFSUBR (Finteractive);
  DEFSUBR (Fcall_interactively);
  DEFSUBR (Fprefix_numeric_value);
}

void
vars_of_callint (void)
{
  DEFVAR_LISP ("current-prefix-arg", &Vcurrent_prefix_arg /*
The value of the prefix argument for this editing command.
It may be a number, or the symbol `-' for just a minus sign as arg,
or a list whose car is a number for just one or more C-U's
or nil if no argument has been specified.
This is what `(interactive "P")' returns.
*/ );
  Vcurrent_prefix_arg = Qnil;

  DEFVAR_LISP ("command-history", &Vcommand_history /*
List of recent commands that read arguments from terminal.
Each command is represented as a form to evaluate.
*/ );
  Vcommand_history = Qnil;

  DEFVAR_LISP ("command-debug-status", &Vcommand_debug_status /*
Debugging status of current interactive command.
Bound each time `call-interactively' is called;
may be set by the debugger as a reminder for itself.
*/ );
  Vcommand_debug_status = Qnil;

#if 0 /* FSFmacs */
  xxDEFVAR_LISP ("mark-even-if-inactive", &Vmark_even_if_inactive /*
*Non-nil means you can use the mark even when inactive.
This option makes a difference in Transient Mark mode.
When the option is non-nil, deactivation of the mark
turns off region highlighting, but commands that use the mark
behave as if the mark were still active.
*/ );
  Vmark_even_if_inactive = Qnil;
#endif

#if 0 /* Doesn't work and is totally ill-conceived anyway. */
  xxDEFVAR_LISP ("mouse-leave-buffer-hook", &Vmouse_leave_buffer_hook /*
Hook to run when about to switch windows with a mouse command.
Its purpose is to give temporary modes such as Isearch mode
a way to turn themselves off when a mouse command switches windows.
*/ );
  Vmouse_leave_buffer_hook = Qnil;
#endif
}
