src/callint.c

   1 /* Call a Lisp function interactively.
   2    Copyright (C) 1985-1986, 1993-1995, 1997, 2000-2017 Free Software
   3    Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software: you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation, either version 3 of the License, or (at
  10 your option) any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20
  21 #include <config.h>
  22
  23 #include "lisp.h"
  24 #include "character.h"
  25 #include "buffer.h"
  26 #include "keyboard.h"
  27 #include "window.h"
  28
  29 static Lisp_Object preserved_fns;
  30
  31 /* Marker used within call-interactively to refer to point.  */
  32 static Lisp_Object point_marker;
  33
  34 /* String for the prompt text used in Fcall_interactively.  */
  35 static Lisp_Object callint_message;
  36 \f
  37 /* ARGSUSED */
  38 DEFUN ("interactive", Finteractive, Sinteractive, 0, UNEVALLED, 0,
  39        doc: /* Specify a way of parsing arguments for interactive use of a function.
  40 For example, write
  41  (defun foo (arg buf) "Doc string" (interactive "P\\nbbuffer: ") .... )
  42  to make ARG be the raw prefix argument, and set BUF to an existing buffer,
  43  when `foo' is called as a command.
  44
  45 The "call" to `interactive' is actually a declaration rather than a
  46  function; it tells `call-interactively' how to read arguments to pass
  47  to the function.  When actually called, `interactive' just returns
  48  nil.
  49
  50 Usually the argument of `interactive' is a string containing a code
  51  letter followed optionally by a prompt.  (Some code letters do not
  52  use I/O to get the argument and do not use prompts.)  To pass several
  53  arguments to the command, concatenate the individual strings,
  54  separating them by newline characters.
  55
  56 Prompts are passed to `format', and may use % escapes to print the
  57  arguments that have already been read.
  58 If the argument is not a string, it is evaluated to get a list of
  59  arguments to pass to the command.
  60 Just `(interactive)' means pass no arguments to the command when
  61  calling interactively.
  62
  63 Code letters available are:
  64 a -- Function name: symbol with a function definition.
  65 b -- Name of existing buffer.
  66 B -- Name of buffer, possibly nonexistent.
  67 c -- Character (no input method is used).
  68 C -- Command name: symbol with interactive function definition.
  69 d -- Value of point as number.  Does not do I/O.
  70 D -- Directory name.
  71 e -- Parameterized event (i.e., one that's a list) that invoked this command.
  72      If used more than once, the Nth `e' returns the Nth parameterized event.
  73      This skips events that are integers or symbols.
  74 f -- Existing file name.
  75 F -- Possibly nonexistent file name.
  76 G -- Possibly nonexistent file name, defaulting to just directory name.
  77 i -- Ignored, i.e. always nil.  Does not do I/O.
  78 k -- Key sequence (downcase the last event if needed to get a definition).
  79 K -- Key sequence to be redefined (do not downcase the last event).
  80 m -- Value of mark as number.  Does not do I/O.
  81 M -- Any string.  Inherits the current input method.
  82 n -- Number read using minibuffer.
  83 N -- Numeric prefix arg, or if none, do like code `n'.
  84 p -- Prefix arg converted to number.  Does not do I/O.
  85 P -- Prefix arg in raw form.  Does not do I/O.
  86 r -- Region: point and mark as 2 numeric args, smallest first.  Does no I/O.
  87 s -- Any string.  Does not inherit the current input method.
  88 S -- Any symbol.
  89 U -- Mouse up event discarded by a previous k or K argument.
  90 v -- Variable name: symbol that is `custom-variable-p'.
  91 x -- Lisp expression read but not evaluated.
  92 X -- Lisp expression read and evaluated.
  93 z -- Coding system.
  94 Z -- Coding system, nil if no prefix arg.
  95
  96 In addition, if the string begins with `*', an error is signaled if
  97   the buffer is read-only.
  98 If `@' appears at the beginning of the string, and if the key sequence
  99  used to invoke the command includes any mouse events, then the window
 100  associated with the first of those events is selected before the
 101  command is run.
 102 If the string begins with `^' and `shift-select-mode' is non-nil,
 103  Emacs first calls the function `handle-shift-selection'.
 104 You may use `@', `*', and `^' together.  They are processed in the
 105  order that they appear, before reading any arguments.
 106 usage: (interactive &optional ARG-DESCRIPTOR)  */
 107        attributes: const)
 108   (Lisp_Object args)
 109 {
 110   return Qnil;
 111 }
 112
 113 /* Quotify EXP: if EXP is constant, return it.
 114    If EXP is not constant, return (quote EXP).  */
 115 static Lisp_Object
 116 quotify_arg (register Lisp_Object exp)
 117 {
 118   if (CONSP (exp)
 119       || (SYMBOLP (exp)
 120           && !NILP (exp) && !EQ (exp, Qt)))
 121     return list2 (Qquote, exp);
 122
 123   return exp;
 124 }
 125
 126 /* Modify EXP by quotifying each element (except the first).  */
 127 static Lisp_Object
 128 quotify_args (Lisp_Object exp)
 129 {
 130   register Lisp_Object tail;
 131   Lisp_Object next;
 132   for (tail = exp; CONSP (tail); tail = next)
 133     {
 134       next = XCDR (tail);
 135       XSETCAR (tail, quotify_arg (XCAR (tail)));
 136     }
 137   return exp;
 138 }
 139
 140 static const char *callint_argfuns[]
 141     = {"", "point", "mark", "region-beginning", "region-end"};
 142
 143 static void
 144 check_mark (bool for_region)
 145 {
 146   Lisp_Object tem;
 147   tem = Fmarker_buffer (BVAR (current_buffer, mark));
 148   if (NILP (tem) || (XBUFFER (tem) != current_buffer))
 149     error (for_region ? "The mark is not set now, so there is no region"
 150            : "The mark is not set now");
 151   if (!NILP (Vtransient_mark_mode) && NILP (Vmark_even_if_inactive)
 152       && NILP (BVAR (current_buffer, mark_active)))
 153     xsignal0 (Qmark_inactive);
 154 }
 155
 156 /* If the list of args INPUT was produced with an explicit call to
 157    `list', look for elements that were computed with
 158    (region-beginning) or (region-end), and put those expressions into
 159    VALUES instead of the present values.
 160
 161    This function doesn't return a value because it modifies elements
 162    of VALUES to do its job.  */
 163
 164 static void
 165 fix_command (Lisp_Object input, Lisp_Object values)
 166 {
 167   /* FIXME: Instead of this ugly hack, we should provide a way for an
 168      interactive spec to return an expression/function that will re-build the
 169      args without user intervention.  */
 170   if (CONSP (input))
 171     {
 172       Lisp_Object car;
 173
 174       car = XCAR (input);
 175       /* Skip through certain special forms.  */
 176       while (EQ (car, Qlet) || EQ (car, Qletx)
 177              || EQ (car, Qsave_excursion)
 178              || EQ (car, Qprogn))
 179         {
 180           while (CONSP (XCDR (input)))
 181             input = XCDR (input);
 182           input = XCAR (input);
 183           if (!CONSP (input))
 184             break;
 185           car = XCAR (input);
 186         }
 187       if (EQ (car, Qlist))
 188         {
 189           Lisp_Object intail, valtail;
 190           for (intail = Fcdr (input), valtail = values;
 191                CONSP (valtail);
 192                intail = Fcdr (intail), valtail = XCDR (valtail))
 193             {
 194               Lisp_Object elt;
 195               elt = Fcar (intail);
 196               if (CONSP (elt))
 197                 {
 198                   Lisp_Object presflag, carelt;
 199                   carelt = XCAR (elt);
 200                   /* If it is (if X Y), look at Y.  */
 201                   if (EQ (carelt, Qif)
 202                       && EQ (Fnthcdr (make_number (3), elt), Qnil))
 203                     elt = Fnth (make_number (2), elt);
 204                   /* If it is (when ... Y), look at Y.  */
 205                   else if (EQ (carelt, Qwhen))
 206                     {
 207                       while (CONSP (XCDR (elt)))
 208                         elt = XCDR (elt);
 209                       elt = Fcar (elt);
 210                     }
 211
 212                   /* If the function call we're looking at
 213                      is a special preserved one, copy the
 214                      whole expression for this argument.  */
 215                   if (CONSP (elt))
 216                     {
 217                       presflag = Fmemq (Fcar (elt), preserved_fns);
 218                       if (!NILP (presflag))
 219                         Fsetcar (valtail, Fcar (intail));
 220                     }
 221                 }
 222             }
 223         }
 224     }
 225 }
 226
 227 /* Helper function to call `read-file-name' from C.  */
 228
 229 static Lisp_Object
 230 read_file_name (Lisp_Object default_filename, Lisp_Object mustmatch,
 231                 Lisp_Object initial, Lisp_Object predicate)
 232 {
 233   return CALLN (Ffuncall, intern ("read-file-name"),
 234                 callint_message, Qnil, default_filename,
 235                 mustmatch, initial, predicate);
 236 }
 237
 238 /* BEWARE: Calling this directly from C would defeat the purpose!  */
 239 DEFUN ("funcall-interactively", Ffuncall_interactively, Sfuncall_interactively,
 240        1, MANY, 0, doc: /* Like `funcall' but marks the call as interactive.
 241 I.e. arrange that within the called function `called-interactively-p' will
 242 return non-nil.
 243 usage: (funcall-interactively FUNCTION &rest ARGUMENTS)  */)
 244      (ptrdiff_t nargs, Lisp_Object *args)
 245 {
 246   ptrdiff_t speccount = SPECPDL_INDEX ();
 247   temporarily_switch_to_single_kboard (NULL);
 248
 249   /* Nothing special to do here, all the work is inside
 250      `called-interactively-p'.  Which will look for us as a marker in the
 251      backtrace.  */
 252   return unbind_to (speccount, Ffuncall (nargs, args));
 253 }
 254
 255 DEFUN ("call-interactively", Fcall_interactively, Scall_interactively, 1, 3, 0,
 256        doc: /* Call FUNCTION, providing args according to its interactive calling specs.
 257 Return the value FUNCTION returns.
 258 The function contains a specification of how to do the argument reading.
 259 In the case of user-defined functions, this is specified by placing a call
 260 to the function `interactive' at the top level of the function body.
 261 See `interactive'.
 262
 263 Optional second arg RECORD-FLAG non-nil
 264 means unconditionally put this command in the command-history.
 265 Otherwise, this is done only if an arg is read using the minibuffer.
 266
 267 Optional third arg KEYS, if given, specifies the sequence of events to
 268 supply, as a vector, if the command inquires which events were used to
 269 invoke it.  If KEYS is omitted or nil, the return value of
 270 `this-command-keys-vector' is used.  */)
 271   (Lisp_Object function, Lisp_Object record_flag, Lisp_Object keys)
 272 {
 273   /* `args' will contain the array of arguments to pass to the function.
 274      `visargs' will contain the same list but in a nicer form, so that if we
 275      pass it to `Fformat_message' it will be understandable to a human.  */
 276   Lisp_Object *args, *visargs;
 277   Lisp_Object specs;
 278   Lisp_Object filter_specs;
 279   Lisp_Object teml;
 280   Lisp_Object up_event;
 281   Lisp_Object enable;
 282   USE_SAFE_ALLOCA;
 283   ptrdiff_t speccount = SPECPDL_INDEX ();
 284
 285   /* The index of the next element of this_command_keys to examine for
 286      the 'e' interactive code.  */
 287   ptrdiff_t next_event;
 288
 289   Lisp_Object prefix_arg;
 290   char *string;
 291   const char *tem;
 292
 293   /* If varies[i] > 0, the i'th argument shouldn't just have its value
 294      in this call quoted in the command history.  It should be
 295      recorded as a call to the function named callint_argfuns[varies[i]].  */
 296   signed char *varies;
 297
 298   ptrdiff_t i, nargs;
 299   ptrdiff_t mark;
 300   bool arg_from_tty = 0;
 301   ptrdiff_t key_count;
 302   bool record_then_fail = 0;
 303
 304   Lisp_Object save_this_command, save_last_command;
 305   Lisp_Object save_this_original_command, save_real_this_command;
 306
 307   save_this_command = Vthis_command;
 308   save_this_original_command = Vthis_original_command;
 309   save_real_this_command = Vreal_this_command;
 310   save_last_command = KVAR (current_kboard, Vlast_command);
 311
 312   if (NILP (keys))
 313     keys = this_command_keys, key_count = this_command_key_count;
 314   else
 315     {
 316       CHECK_VECTOR (keys);
 317       key_count = ASIZE (keys);
 318     }
 319
 320   /* Save this now, since use of minibuffer will clobber it.  */
 321   prefix_arg = Vcurrent_prefix_arg;
 322
 323   if (SYMBOLP (function))
 324     enable = Fget (function, Qenable_recursive_minibuffers);
 325   else
 326     enable = Qnil;
 327
 328   specs = Qnil;
 329   string = 0;
 330   /* The idea of FILTER_SPECS is to provide a way to
 331      specify how to represent the arguments in command history.
 332      The feature is not fully implemented.  */
 333   filter_specs = Qnil;
 334
 335   /* If k or K discard an up-event, save it here so it can be retrieved with
 336      U.  */
 337   up_event = Qnil;
 338
 339   /* Set SPECS to the interactive form, or barf if not interactive.  */
 340   {
 341     Lisp_Object form;
 342     form = Finteractive_form (function);
 343     if (CONSP (form))
 344       specs = filter_specs = Fcar (XCDR (form));
 345     else
 346       wrong_type_argument (Qcommandp, function);
 347   }
 348
 349   /* If SPECS is not a string, invent one.  */
 350   if (! STRINGP (specs))
 351     {
 352       Lisp_Object input;
 353       Lisp_Object funval = Findirect_function (function, Qt);
 354       uintmax_t events = num_input_events;
 355       input = specs;
 356       /* Compute the arg values using the user's expression.  */
 357       specs = Feval (specs,
 358                      CONSP (funval) && EQ (Qclosure, XCAR (funval))
 359                      ? CAR_SAFE (XCDR (funval)) : Qnil);
 360       if (events != num_input_events || !NILP (record_flag))
 361         {
 362           /* We should record this command on the command history.  */
 363           Lisp_Object values;
 364           Lisp_Object this_cmd;
 365           /* Make a copy of the list of values, for the command history,
 366              and turn them into things we can eval.  */
 367           values = quotify_args (Fcopy_sequence (specs));
 368           fix_command (input, values);
 369           this_cmd = Fcons (function, values);
 370           if (history_delete_duplicates)
 371             Vcommand_history = Fdelete (this_cmd, Vcommand_history);
 372           Vcommand_history = Fcons (this_cmd, Vcommand_history);
 373
 374           /* Don't keep command history around forever.  */
 375           if (INTEGERP (Vhistory_length) && XINT (Vhistory_length) > 0)
 376             {
 377               teml = Fnthcdr (Vhistory_length, Vcommand_history);
 378               if (CONSP (teml))
 379                 XSETCDR (teml, Qnil);
 380             }
 381         }
 382
 383       Vthis_command = save_this_command;
 384       Vthis_original_command = save_this_original_command;
 385       Vreal_this_command = save_real_this_command;
 386       kset_last_command (current_kboard, save_last_command);
 387
 388       Lisp_Object result
 389         = unbind_to (speccount, CALLN (Fapply, Qfuncall_interactively,
 390                                        function, specs));
 391       SAFE_FREE ();
 392       return result;
 393     }
 394
 395   /* SPECS is set to a string; use it as an interactive prompt.
 396      Copy it so that STRING will be valid even if a GC relocates SPECS.  */
 397   SAFE_ALLOCA_STRING (string, specs);
 398
 399   /* Here if function specifies a string to control parsing the defaults.  */
 400
 401   /* Set next_event to point to the first event with parameters.  */
 402   for (next_event = 0; next_event < key_count; next_event++)
 403     if (EVENT_HAS_PARAMETERS (AREF (keys, next_event)))
 404       break;
 405
 406   /* Handle special starting chars `*' and `@'.  Also `-'.  */
 407   /* Note that `+' is reserved for user extensions.  */
 408   while (1)
 409     {
 410       if (*string == '+')
 411         error ("`+' is not used in `interactive' for ordinary commands");
 412       else if (*string == '*')
 413         {
 414           string++;
 415           if (!NILP (BVAR (current_buffer, read_only)))
 416             {
 417               if (!NILP (record_flag))
 418                 {
 419                   char *p = string;
 420                   while (*p)
 421                     {
 422                       if (! (*p == 'r' || *p == 'p' || *p == 'P'
 423                              || *p == '\n'))
 424                         Fbarf_if_buffer_read_only (Qnil);
 425                       p++;
 426                     }
 427                   record_then_fail = 1;
 428                 }
 429               else
 430                 Fbarf_if_buffer_read_only (Qnil);
 431             }
 432         }
 433       /* Ignore this for semi-compatibility with Lucid.  */
 434       else if (*string == '-')
 435         string++;
 436       else if (*string == '@')
 437         {
 438           Lisp_Object event, w;
 439
 440           event = (next_event < key_count
 441                    ? AREF (keys, next_event)
 442                    : Qnil);
 443           if (EVENT_HAS_PARAMETERS (event)
 444               && (w = XCDR (event), CONSP (w))
 445               && (w = XCAR (w), CONSP (w))
 446               && (w = XCAR (w), WINDOWP (w)))
 447             {
 448               if (MINI_WINDOW_P (XWINDOW (w))
 449                   && ! (minibuf_level > 0 && EQ (w, minibuf_window)))
 450                 error ("Attempt to select inactive minibuffer window");
 451
 452               /* If the current buffer wants to clean up, let it.  */
 453               run_hook (Qmouse_leave_buffer_hook);
 454
 455               Fselect_window (w, Qnil);
 456             }
 457           string++;
 458         }
 459       else if (*string == '^')
 460         {
 461           call0 (Qhandle_shift_selection);
 462           string++;
 463         }
 464       else break;
 465     }
 466
 467   /* Count the number of arguments, which is two (the function itself and
 468      `funcall-interactively') plus the number of arguments the interactive spec
 469      would have us give to the function.  */
 470   tem = string;
 471   for (nargs = 2; *tem; )
 472     {
 473       /* 'r' specifications ("point and mark as 2 numeric args")
 474          produce *two* arguments.  */
 475       if (*tem == 'r')
 476         nargs += 2;
 477       else
 478         nargs++;
 479       tem = strchr (tem, '\n');
 480       if (tem)
 481         ++tem;
 482       else
 483         break;
 484     }
 485
 486   if (MOST_POSITIVE_FIXNUM < min (PTRDIFF_MAX, SIZE_MAX) / word_size
 487       && MOST_POSITIVE_FIXNUM < nargs)
 488     memory_full (SIZE_MAX);
 489
 490   /* Allocate them all at one go.  This wastes a bit of memory, but
 491      it's OK to trade space for speed.  */
 492   SAFE_NALLOCA (args, 3, nargs);
 493   visargs = args + nargs;
 494   varies = (signed char *) (visargs + nargs);
 495
 496   memclear (args, nargs * (2 * word_size + 1));
 497
 498   if (!NILP (enable))
 499     specbind (Qenable_recursive_minibuffers, Qt);
 500
 501   tem = string;
 502   for (i = 2; *tem; i++)
 503     {
 504       visargs[1] = make_string (tem + 1, strcspn (tem + 1, "\n"));
 505       if (strchr (SSDATA (visargs[1]), '%'))
 506         callint_message = Fformat_message (i - 1, visargs + 1);
 507       else
 508         callint_message = visargs[1];
 509
 510       switch (*tem)
 511         {
 512         case 'a':               /* Symbol defined as a function.  */
 513           visargs[i] = Fcompleting_read (callint_message,
 514                                          Vobarray, Qfboundp, Qt,
 515                                          Qnil, Qnil, Qnil, Qnil);
 516           /* Passing args[i] directly stimulates compiler bug.  */
 517           teml = visargs[i];
 518           args[i] = Fintern (teml, Qnil);
 519           break;
 520
 521         case 'b':               /* Name of existing buffer.  */
 522           args[i] = Fcurrent_buffer ();
 523           if (EQ (selected_window, minibuf_window))
 524             args[i] = Fother_buffer (args[i], Qnil, Qnil);
 525           args[i] = Fread_buffer (callint_message, args[i], Qt, Qnil);
 526           break;
 527
 528         case 'B':               /* Name of buffer, possibly nonexistent.  */
 529           args[i] = Fread_buffer (callint_message,
 530                                   Fother_buffer (Fcurrent_buffer (), Qnil, Qnil),
 531                                   Qnil, Qnil);
 532           break;
 533
 534         case 'c':               /* Character.  */
 535           /* Prompt in `minibuffer-prompt' face.  */
 536           Fput_text_property (make_number (0),
 537                               make_number (SCHARS (callint_message)),
 538                               Qface, Qminibuffer_prompt, callint_message);
 539           args[i] = Fread_char (callint_message, Qnil, Qnil);
 540           message1_nolog (0);
 541           /* Passing args[i] directly stimulates compiler bug.  */
 542           teml = args[i];
 543           /* See bug#8479.  */
 544           if (! CHARACTERP (teml)) error ("Non-character input-event");
 545           visargs[i] = Fchar_to_string (teml);
 546           break;
 547
 548         case 'C':             /* Command: symbol with interactive function.  */
 549           visargs[i] = Fcompleting_read (callint_message,
 550                                          Vobarray, Qcommandp,
 551                                          Qt, Qnil, Qnil, Qnil, Qnil);
 552           /* Passing args[i] directly stimulates compiler bug.  */
 553           teml = visargs[i];
 554           args[i] = Fintern (teml, Qnil);
 555           break;
 556
 557         case 'd':               /* Value of point.  Does not do I/O.  */
 558           set_marker_both (point_marker, Qnil, PT, PT_BYTE);
 559           args[i] = point_marker;
 560           /* visargs[i] = Qnil; */
 561           varies[i] = 1;
 562           break;
 563
 564         case 'D':               /* Directory name.  */
 565           args[i] = read_file_name (BVAR (current_buffer, directory), Qlambda, Qnil,
 566                                     Qfile_directory_p);
 567           break;
 568
 569         case 'f':               /* Existing file name.  */
 570           args[i] = read_file_name (Qnil, Qlambda, Qnil, Qnil);
 571           break;
 572
 573         case 'F':               /* Possibly nonexistent file name.  */
 574           args[i] = read_file_name (Qnil, Qnil, Qnil, Qnil);
 575           break;
 576
 577         case 'G':               /* Possibly nonexistent file name,
 578                                    default to directory alone.  */
 579           args[i] = read_file_name (Qnil, Qnil, empty_unibyte_string, Qnil);
 580           break;
 581
 582         case 'i':               /* Ignore an argument -- Does not do I/O.  */
 583           varies[i] = -1;
 584           break;
 585
 586         case 'k':               /* Key sequence.  */
 587           {
 588             ptrdiff_t speccount1 = SPECPDL_INDEX ();
 589             specbind (Qcursor_in_echo_area, Qt);
 590             /* Prompt in `minibuffer-prompt' face.  */
 591             Fput_text_property (make_number (0),
 592                                 make_number (SCHARS (callint_message)),
 593                                 Qface, Qminibuffer_prompt, callint_message);
 594             args[i] = Fread_key_sequence (callint_message,
 595                                           Qnil, Qnil, Qnil, Qnil);
 596             unbind_to (speccount1, Qnil);
 597             teml = args[i];
 598             visargs[i] = Fkey_description (teml, Qnil);
 599
 600             /* If the key sequence ends with a down-event,
 601                discard the following up-event.  */
 602             teml = Faref (args[i], make_number (XINT (Flength (args[i])) - 1));
 603             if (CONSP (teml))
 604               teml = XCAR (teml);
 605             if (SYMBOLP (teml))
 606               {
 607                 Lisp_Object tem2;
 608
 609                 teml = Fget (teml, Qevent_symbol_elements);
 610                 /* Ignore first element, which is the base key.  */
 611                 tem2 = Fmemq (Qdown, Fcdr (teml));
 612                 if (! NILP (tem2))
 613                   up_event = Fread_event (Qnil, Qnil, Qnil);
 614               }
 615           }
 616           break;
 617
 618         case 'K':               /* Key sequence to be defined.  */
 619           {
 620             ptrdiff_t speccount1 = SPECPDL_INDEX ();
 621             specbind (Qcursor_in_echo_area, Qt);
 622             /* Prompt in `minibuffer-prompt' face.  */
 623             Fput_text_property (make_number (0),
 624                                 make_number (SCHARS (callint_message)),
 625                                 Qface, Qminibuffer_prompt, callint_message);
 626             args[i] = Fread_key_sequence_vector (callint_message,
 627                                                  Qnil, Qt, Qnil, Qnil);
 628             teml = args[i];
 629             visargs[i] = Fkey_description (teml, Qnil);
 630             unbind_to (speccount1, Qnil);
 631
 632             /* If the key sequence ends with a down-event,
 633                discard the following up-event.  */
 634             teml = Faref (args[i], make_number (XINT (Flength (args[i])) - 1));
 635             if (CONSP (teml))
 636               teml = XCAR (teml);
 637             if (SYMBOLP (teml))
 638               {
 639                 Lisp_Object tem2;
 640
 641                 teml = Fget (teml, Qevent_symbol_elements);
 642                 /* Ignore first element, which is the base key.  */
 643                 tem2 = Fmemq (Qdown, Fcdr (teml));
 644                 if (! NILP (tem2))
 645                   up_event = Fread_event (Qnil, Qnil, Qnil);
 646               }
 647           }
 648           break;
 649
 650         case 'U':               /* Up event from last k or K.  */
 651           if (!NILP (up_event))
 652             {
 653               args[i] = Fmake_vector (make_number (1), up_event);
 654               up_event = Qnil;
 655               teml = args[i];
 656               visargs[i] = Fkey_description (teml, Qnil);
 657             }
 658           break;
 659
 660         case 'e':               /* The invoking event.  */
 661           if (next_event >= key_count)
 662             error ("%s must be bound to an event with parameters",
 663                    (SYMBOLP (function)
 664                     ? SSDATA (SYMBOL_NAME (function))
 665                     : "command"));
 666           args[i] = AREF (keys, next_event);
 667           next_event++;
 668           varies[i] = -1;
 669
 670           /* Find the next parameterized event.  */
 671           while (next_event < key_count
 672                  && !(EVENT_HAS_PARAMETERS (AREF (keys, next_event))))
 673             next_event++;
 674
 675           break;
 676
 677         case 'm':               /* Value of mark.  Does not do I/O.  */
 678           check_mark (0);
 679           /* visargs[i] = Qnil; */
 680           args[i] = BVAR (current_buffer, mark);
 681           varies[i] = 2;
 682           break;
 683
 684         case 'M':               /* String read via minibuffer with
 685                                    inheriting the current input method.  */
 686           args[i] = Fread_string (callint_message,
 687                                   Qnil, Qnil, Qnil, Qt);
 688           break;
 689
 690         case 'N':     /* Prefix arg as number, else number from minibuffer.  */
 691           if (!NILP (prefix_arg))
 692             goto have_prefix_arg;
 693           FALLTHROUGH;
 694         case 'n':               /* Read number from minibuffer.  */
 695           args[i] = call1 (Qread_number, callint_message);
 696           /* Passing args[i] directly stimulates compiler bug.  */
 697           teml = args[i];
 698           visargs[i] = Fnumber_to_string (teml);
 699           break;
 700
 701         case 'P':               /* Prefix arg in raw form.  Does no I/O.  */
 702           args[i] = prefix_arg;
 703           /* visargs[i] = Qnil; */
 704           varies[i] = -1;
 705           break;
 706
 707         case 'p':               /* Prefix arg converted to number.  No I/O.  */
 708         have_prefix_arg:
 709           args[i] = Fprefix_numeric_value (prefix_arg);
 710           /* visargs[i] = Qnil; */
 711           varies[i] = -1;
 712           break;
 713
 714         case 'r':               /* Region, point and mark as 2 args.  */
 715           check_mark (1);
 716           set_marker_both (point_marker, Qnil, PT, PT_BYTE);
 717           /* visargs[i+1] = Qnil; */
 718           mark = marker_position (BVAR (current_buffer, mark));
 719           /* visargs[i] = Qnil; */
 720           args[i] = PT < mark ? point_marker : BVAR (current_buffer, mark);
 721           varies[i] = 3;
 722           args[++i] = PT > mark ? point_marker : BVAR (current_buffer, mark);
 723           varies[i] = 4;
 724           break;
 725
 726         case 's':               /* String read via minibuffer without
 727                                    inheriting the current input method.  */
 728           args[i] = Fread_string (callint_message,
 729                                   Qnil, Qnil, Qnil, Qnil);
 730           break;
 731
 732         case 'S':               /* Any symbol.  */
 733           visargs[i] = Fread_string (callint_message,
 734                                      Qnil, Qnil, Qnil, Qnil);
 735           /* Passing args[i] directly stimulates compiler bug.  */
 736           teml = visargs[i];
 737           args[i] = Fintern (teml, Qnil);
 738           break;
 739
 740         case 'v':               /* Variable name: symbol that is
 741                                    custom-variable-p.  */
 742           args[i] = Fread_variable (callint_message, Qnil);
 743           visargs[i] = last_minibuf_string;
 744           break;
 745
 746         case 'x':               /* Lisp expression read but not evaluated.  */
 747           args[i] = call1 (intern ("read-minibuffer"), callint_message);
 748           visargs[i] = last_minibuf_string;
 749           break;
 750
 751         case 'X':               /* Lisp expression read and evaluated.  */
 752           args[i] = call1 (intern ("eval-minibuffer"), callint_message);
 753           visargs[i] = last_minibuf_string;
 754           break;
 755
 756         case 'Z':               /* Coding-system symbol, or ignore the
 757                                    argument if no prefix.  */
 758           if (NILP (prefix_arg))
 759             {
 760               /* args[i] = Qnil; */
 761               varies[i] = -1;
 762             }
 763           else
 764             {
 765               args[i]
 766                 = Fread_non_nil_coding_system (callint_message);
 767               visargs[i] = last_minibuf_string;
 768             }
 769           break;
 770
 771         case 'z':               /* Coding-system symbol or nil.  */
 772           args[i] = Fread_coding_system (callint_message, Qnil);
 773           visargs[i] = last_minibuf_string;
 774           break;
 775
 776           /* We have a case for `+' so we get an error
 777              if anyone tries to define one here.  */
 778         case '+':
 779         default:
 780           error ("Invalid control letter `%c' (#o%03o, #x%04x) in interactive calling string",
 781                  STRING_CHAR ((unsigned char *) tem),
 782                  (unsigned) STRING_CHAR ((unsigned char *) tem),
 783                  (unsigned) STRING_CHAR ((unsigned char *) tem));
 784         }
 785
 786       if (varies[i] == 0)
 787         arg_from_tty = 1;
 788
 789       if (NILP (visargs[i]) && STRINGP (args[i]))
 790         visargs[i] = args[i];
 791
 792       tem = strchr (tem, '\n');
 793       if (tem) tem++;
 794       else tem = "";
 795     }
 796   unbind_to (speccount, Qnil);
 797
 798   maybe_quit ();
 799
 800   args[0] = Qfuncall_interactively;
 801   args[1] = function;
 802
 803   if (arg_from_tty || !NILP (record_flag))
 804     {
 805       /* We don't need `visargs' any more, so let's recycle it since we need
 806          an array of just the same size.  */
 807       visargs[1] = function;
 808       for (i = 2; i < nargs; i++)
 809         {
 810           if (varies[i] > 0)
 811             visargs[i] = list1 (intern (callint_argfuns[varies[i]]));
 812           else
 813             visargs[i] = quotify_arg (args[i]);
 814         }
 815       Vcommand_history = Fcons (Flist (nargs - 1, visargs + 1),
 816                                 Vcommand_history);
 817       /* Don't keep command history around forever.  */
 818       if (INTEGERP (Vhistory_length) && XINT (Vhistory_length) > 0)
 819         {
 820           teml = Fnthcdr (Vhistory_length, Vcommand_history);
 821           if (CONSP (teml))
 822             XSETCDR (teml, Qnil);
 823         }
 824     }
 825
 826   /* If we used a marker to hold point, mark, or an end of the region,
 827      temporarily, convert it to an integer now.  */
 828   for (i = 2; i < nargs; i++)
 829     if (varies[i] >= 1 && varies[i] <= 4)
 830       XSETINT (args[i], marker_position (args[i]));
 831
 832   if (record_then_fail)
 833     Fbarf_if_buffer_read_only (Qnil);
 834
 835   Vthis_command = save_this_command;
 836   Vthis_original_command = save_this_original_command;
 837   Vreal_this_command = save_real_this_command;
 838   kset_last_command (current_kboard, save_last_command);
 839
 840   {
 841     Lisp_Object val;
 842     specbind (Qcommand_debug_status, Qnil);
 843
 844     val = Ffuncall (nargs, args);
 845     val = unbind_to (speccount, val);
 846     SAFE_FREE ();
 847     return val;
 848   }
 849 }
 850
 851 DEFUN ("prefix-numeric-value", Fprefix_numeric_value, Sprefix_numeric_value,
 852        1, 1, 0,
 853        doc: /* Return numeric meaning of raw prefix argument RAW.
 854 A raw prefix argument is what you get from `(interactive "P")'.
 855 Its numeric meaning is what you would get from `(interactive "p")'.  */)
 856   (Lisp_Object raw)
 857 {
 858   Lisp_Object val;
 859
 860   if (NILP (raw))
 861     XSETFASTINT (val, 1);
 862   else if (EQ (raw, Qminus))
 863     XSETINT (val, -1);
 864   else if (CONSP (raw) && INTEGERP (XCAR (raw)))
 865     XSETINT (val, XINT (XCAR (raw)));
 866   else if (INTEGERP (raw))
 867     val = raw;
 868   else
 869     XSETFASTINT (val, 1);
 870
 871   return val;
 872 }
 873
 874 void
 875 syms_of_callint (void)
 876 {
 877   point_marker = Fmake_marker ();
 878   staticpro (&point_marker);
 879
 880   callint_message = Qnil;
 881   staticpro (&callint_message);
 882
 883   preserved_fns = listn (CONSTYPE_PURE, 4,
 884                          intern_c_string ("region-beginning"),
 885                          intern_c_string ("region-end"),
 886                          intern_c_string ("point"),
 887                          intern_c_string ("mark"));
 888
 889   DEFSYM (Qlist, "list");
 890   DEFSYM (Qlet, "let");
 891   DEFSYM (Qif, "if");
 892   DEFSYM (Qwhen, "when");
 893   DEFSYM (Qletx, "let*");
 894   DEFSYM (Qsave_excursion, "save-excursion");
 895   DEFSYM (Qprogn, "progn");
 896   DEFSYM (Qminus, "-");
 897   DEFSYM (Qplus, "+");
 898   DEFSYM (Qhandle_shift_selection, "handle-shift-selection");
 899   DEFSYM (Qread_number, "read-number");
 900   DEFSYM (Qfuncall_interactively, "funcall-interactively");
 901   DEFSYM (Qcommand_debug_status, "command-debug-status");
 902   DEFSYM (Qenable_recursive_minibuffers, "enable-recursive-minibuffers");
 903   DEFSYM (Qmouse_leave_buffer_hook, "mouse-leave-buffer-hook");
 904
 905   DEFVAR_KBOARD ("prefix-arg", Vprefix_arg,
 906                  doc: /* The value of the prefix argument for the next editing command.
 907 It may be a number, or the symbol `-' for just a minus sign as arg,
 908 or a list whose car is a number for just one or more C-u's
 909 or nil if no argument has been specified.
 910
 911 You cannot examine this variable to find the argument for this command
 912 since it has been set to nil by the time you can look.
 913 Instead, you should use the variable `current-prefix-arg', although
 914 normally commands can get this prefix argument with (interactive "P").  */);
 915
 916   DEFVAR_KBOARD ("last-prefix-arg", Vlast_prefix_arg,
 917                  doc: /* The value of the prefix argument for the previous editing command.
 918 See `prefix-arg' for the meaning of the value.  */);
 919
 920   DEFVAR_LISP ("current-prefix-arg", Vcurrent_prefix_arg,
 921                doc: /* The value of the prefix argument for this editing command.
 922 It may be a number, or the symbol `-' for just a minus sign as arg,
 923 or a list whose car is a number for just one or more C-u's
 924 or nil if no argument has been specified.
 925 This is what `(interactive \"P\")' returns.  */);
 926   Vcurrent_prefix_arg = Qnil;
 927
 928   DEFVAR_LISP ("command-history", Vcommand_history,
 929                doc: /* List of recent commands that read arguments from terminal.
 930 Each command is represented as a form to evaluate.
 931
 932 Maximum length of the history list is determined by the value
 933 of `history-length', which see.  */);
 934   Vcommand_history = Qnil;
 935
 936   DEFVAR_LISP ("command-debug-status", Vcommand_debug_status,
 937                doc: /* Debugging status of current interactive command.
 938 Bound each time `call-interactively' is called;
 939 may be set by the debugger as a reminder for itself.  */);
 940   Vcommand_debug_status = Qnil;
 941
 942   DEFVAR_LISP ("mark-even-if-inactive", Vmark_even_if_inactive,
 943                doc: /* Non-nil means you can use the mark even when inactive.
 944 This option makes a difference in Transient Mark mode.
 945 When the option is non-nil, deactivation of the mark
 946 turns off region highlighting, but commands that use the mark
 947 behave as if the mark were still active.  */);
 948   Vmark_even_if_inactive = Qt;
 949
 950   DEFVAR_LISP ("mouse-leave-buffer-hook", Vmouse_leave_buffer_hook,
 951                doc: /* Hook to run when about to switch windows with a mouse command.
 952 Its purpose is to give temporary modes such as Isearch mode
 953 a way to turn themselves off when a mouse command switches windows.  */);
 954   Vmouse_leave_buffer_hook = Qnil;
 955
 956   defsubr (&Sinteractive);
 957   defsubr (&Scall_interactively);
 958   defsubr (&Sfuncall_interactively);
 959   defsubr (&Sprefix_numeric_value);
 960 }