lread.c 120 KB
Newer Older
Jim Blandy's avatar
Jim Blandy committed
1
/* Lisp parsing and input streams.
2 3
   Copyright (C) 1985, 1986, 1987, 1988, 1989, 1993, 1994, 1995,
                 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
Glenn Morris's avatar
Glenn Morris committed
4
                 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
5 6 7

This file is part of GNU Emacs.

8
GNU Emacs is free software: you can redistribute it and/or modify
Jim Blandy's avatar
Jim Blandy committed
9
it under the terms of the GNU General Public License as published by
10 11
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Jim Blandy's avatar
Jim Blandy committed
12 13 14 15 16 17 18

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
19
along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
Jim Blandy's avatar
Jim Blandy committed
20 21


Richard M. Stallman's avatar
Richard M. Stallman committed
22
#include <config.h>
Jim Blandy's avatar
Jim Blandy committed
23 24 25 26
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
27
#include <errno.h>
28
#include <setjmp.h>
Jim Blandy's avatar
Jim Blandy committed
29
#include "lisp.h"
30
#include "intervals.h"
Jim Blandy's avatar
Jim Blandy committed
31
#include "buffer.h"
Kenichi Handa's avatar
Kenichi Handa committed
32
#include "character.h"
Karl Heuer's avatar
Karl Heuer committed
33
#include "charset.h"
Kenichi Handa's avatar
Kenichi Handa committed
34
#include "coding.h"
35
#include <epaths.h>
Jim Blandy's avatar
Jim Blandy committed
36
#include "commands.h"
Jim Blandy's avatar
Jim Blandy committed
37
#include "keyboard.h"
38
#include "frame.h"
39
#include "termhooks.h"
40
#include "coding.h"
YAMAMOTO Mitsuharu's avatar
YAMAMOTO Mitsuharu committed
41
#include "blockinput.h"
Jim Blandy's avatar
Jim Blandy committed
42

43 44 45 46 47 48 49
#ifdef MSDOS
#if __DJGPP__ < 2
#include <unistd.h>	/* to get X_OK */
#endif
#include "msdos.h"
#endif

Andreas Schwab's avatar
Andreas Schwab committed
50 51 52 53
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

Jim Blandy's avatar
Jim Blandy committed
54 55 56 57 58 59
#ifndef X_OK
#define X_OK 01
#endif

#include <math.h>

Richard M. Stallman's avatar
Richard M. Stallman committed
60 61 62 63
#ifdef HAVE_SETLOCALE
#include <locale.h>
#endif /* HAVE_SETLOCALE */

Dave Love's avatar
Dave Love committed
64 65 66
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
Richard M. Stallman's avatar
Richard M. Stallman committed
67 68 69 70
#ifndef O_RDONLY
#define O_RDONLY 0
#endif

71
#ifdef HAVE_FSEEKO
72 73 74 75 76 77 78
#define file_offset off_t
#define file_tell ftello
#else
#define file_offset long
#define file_tell ftell
#endif

79
#ifndef USE_CRT_DLL
80
extern int errno;
81
#endif
82

83
Lisp_Object Qread_char, Qget_file_char, Qstandard_input, Qcurrent_load_list;
Jim Blandy's avatar
Jim Blandy committed
84
Lisp_Object Qvariable_documentation, Vvalues, Vstandard_input, Vafter_load_alist;
85
Lisp_Object Qascii_character, Qload, Qload_file_name;
86
Lisp_Object Qbackquote, Qcomma, Qcomma_at, Qcomma_dot, Qfunction;
87
Lisp_Object Qinhibit_file_name_operation;
88
Lisp_Object Qeval_buffer_list, Veval_buffer_list;
89
Lisp_Object Qfile_truename, Qdo_after_load_evaluation; /* ACM 2006/5/16 */
90

Kenichi Handa's avatar
Kenichi Handa committed
91 92 93 94 95 96
/* Used instead of Qget_file_char while loading *.elc files compiled
   by Emacs 21 or older.  */
static Lisp_Object Qget_emacs_mule_file_char;

static Lisp_Object Qload_force_doc_strings;

97
extern Lisp_Object Qevent_symbol_element_mask;
98
extern Lisp_Object Qfile_exists_p;
Jim Blandy's avatar
Jim Blandy committed
99

Glenn Morris's avatar
Glenn Morris committed
100
/* non-zero if inside `load' */
Jim Blandy's avatar
Jim Blandy committed
101 102
int load_in_progress;

103 104 105
/* Directory in which the sources were found.  */
Lisp_Object Vsource_directory;

106
/* Search path and suffixes for files to be loaded. */
107
Lisp_Object Vload_path, Vload_suffixes, Vload_file_rep_suffixes;
Jim Blandy's avatar
Jim Blandy committed
108

Karl Heuer's avatar
Karl Heuer committed
109 110 111
/* File name of user's init file.  */
Lisp_Object Vuser_init_file;

112 113 114 115
/* This is the user-visible association list that maps features to
   lists of defs in their load files. */
Lisp_Object Vload_history;

116
/* This is used to build the load history. */
117 118
Lisp_Object Vcurrent_load_list;

119 120 121
/* List of files that were preloaded.  */
Lisp_Object Vpreloaded_file_list;

122 123 124
/* Name of file actually being read by `load'.  */
Lisp_Object Vload_file_name;

125 126 127
/* Function to use for reading, in `load' and friends.  */
Lisp_Object Vload_read_function;

128 129 130 131 132 133
/* The association list of objects read with the #n=object form.
   Each member of the list has the form (n . object), and is used to
   look up the object for the corresponding #n# construct.
   It must be set to nil before all top-level calls to read0.  */
Lisp_Object read_objects;

134 135 136
/* Nonzero means load should forcibly load all dynamic doc strings.  */
static int load_force_doc_strings;

137 138 139
/* Nonzero means read should convert strings to unibyte.  */
static int load_convert_to_unibyte;

Kenichi Handa's avatar
Kenichi Handa committed
140 141 142 143 144
/* Nonzero means READCHAR should read bytes one by one (not character)
   when READCHARFUN is Qget_file_char or Qget_emacs_mule_file_char.
   This is set to 1 by read1 temporarily while handling #@NUMBER.  */
static int load_each_byte;

145
/* Function to use for loading an Emacs Lisp source file (not
Karl Heuer's avatar
Karl Heuer committed
146 147 148
   compiled) instead of readevalloop.  */
Lisp_Object Vload_source_file_function;

149 150 151
/* List of all DEFVAR_BOOL variables.  Used by the byte optimizer.  */
Lisp_Object Vbyte_boolean_vars;

152 153 154 155 156 157 158
/* Whether or not to add a `read-positions' property to symbols
   read. */
Lisp_Object Vread_with_symbol_positions;

/* List of (SYMBOL . POSITION) accumulated so far. */
Lisp_Object Vread_symbol_positions_list;

159 160 161
/* List of descriptors now open for Fload.  */
static Lisp_Object load_descriptor_list;

162
/* File for get_file_char to read from.  Use by load.  */
Jim Blandy's avatar
Jim Blandy committed
163 164 165 166 167
static FILE *instream;

/* When nonzero, read conses in pure space */
static int read_pure;

168
/* For use within read-from-string (this reader is non-reentrant!!)  */
Jim Blandy's avatar
Jim Blandy committed
169
static int read_from_string_index;
170
static int read_from_string_index_byte;
Jim Blandy's avatar
Jim Blandy committed
171
static int read_from_string_limit;
172

173 174 175
/* Number of characters read in the current call to Fread or
   Fread_from_string. */
static int readchar_count;
176

177
/* This contains the last string skipped with #@.  */
178 179 180 181 182 183
static char *saved_doc_string;
/* Length of buffer allocated in saved_doc_string.  */
static int saved_doc_string_size;
/* Length of actual data in saved_doc_string.  */
static int saved_doc_string_length;
/* This is the file position that string came from.  */
184
static file_offset saved_doc_string_position;
185

186 187 188 189 190 191 192 193 194
/* This contains the previous string skipped with #@.
   We copy it from saved_doc_string when a new string
   is put in saved_doc_string.  */
static char *prev_saved_doc_string;
/* Length of buffer allocated in prev_saved_doc_string.  */
static int prev_saved_doc_string_size;
/* Length of actual data in prev_saved_doc_string.  */
static int prev_saved_doc_string_length;
/* This is the file position that string came from.  */
195
static file_offset prev_saved_doc_string_position;
196

197 198 199 200 201
/* Nonzero means inside a new-style backquote
   with no surrounding parentheses.
   Fread initializes this to zero, so we need not specbind it
   or worry about what happens to it when there is an error.  */
static int new_backquote_flag;
202
static Lisp_Object Vold_style_backquotes, Qold_style_backquotes;
203 204 205 206

/* A list of file names for files being loaded in Fload.  Used to
   check for recursive loads.  */

Lute Kamstra's avatar
Lute Kamstra committed
207
static Lisp_Object Vloads_in_progress;
208

209 210 211 212 213 214 215 216
/* Non-zero means load dangerous compiled Lisp files.  */

int load_dangerous_libraries;

/* A regular expression used to detect files compiled with Emacs.  */

static Lisp_Object Vbytecomp_version_regexp;

Kenichi Handa's avatar
Kenichi Handa committed
217 218 219
static int read_emacs_mule_char P_ ((int, int (*) (int, Lisp_Object),
				     Lisp_Object));

220
static void readevalloop P_ ((Lisp_Object, FILE*, Lisp_Object,
221
			      Lisp_Object (*) (), int,
222
			      Lisp_Object, Lisp_Object,
223 224 225 226
			      Lisp_Object, Lisp_Object));
static Lisp_Object load_unwind P_ ((Lisp_Object));
static Lisp_Object load_descriptor_unwind P_ ((Lisp_Object));

227
static void invalid_syntax P_ ((const char *, int)) NO_RETURN;
228
static void end_of_file_error P_ (()) NO_RETURN;
229

Jim Blandy's avatar
Jim Blandy committed
230

Kenichi Handa's avatar
Kenichi Handa committed
231 232 233 234 235 236 237 238 239 240
/* Functions that read one byte from the current source READCHARFUN
   or unreads one byte.  If the integer argument C is -1, it returns
   one read byte, or -1 when there's no more byte in the source.  If C
   is 0 or positive, it unreads C, and the return value is not
   interesting.  */

static int readbyte_for_lambda P_ ((int, Lisp_Object));
static int readbyte_from_file P_ ((int, Lisp_Object));
static int readbyte_from_string P_ ((int, Lisp_Object));

Jim Blandy's avatar
Jim Blandy committed
241 242
/* Handle unreading and rereading of characters.
   Write READCHAR to read a character,
Karl Heuer's avatar
Karl Heuer committed
243 244
   UNREAD(c) to unread c to be read again.

Kenichi Handa's avatar
Kenichi Handa committed
245
   These macros correctly read/unread multibyte characters.  */
Jim Blandy's avatar
Jim Blandy committed
246

247
#define READCHAR readchar (readcharfun, NULL)
Jim Blandy's avatar
Jim Blandy committed
248 249
#define UNREAD(c) unreadchar (readcharfun, c)

250 251 252
/* Same as READCHAR but set *MULTIBYTE to the multibyteness of the source.  */
#define READCHAR_REPORT_MULTIBYTE(multibyte) readchar (readcharfun, multibyte)

Kenichi Handa's avatar
Kenichi Handa committed
253
/* When READCHARFUN is Qget_file_char, Qget_emacs_mule_file_char,
Kenichi Handa's avatar
Kenichi Handa committed
254 255
   Qlambda, or a cons, we use this to keep an unread character because
   a file stream can't handle multibyte-char unreading.  The value -1
Kenichi Handa's avatar
Kenichi Handa committed
256 257 258
   means that there's no unread character. */
static int unread_char;

Jim Blandy's avatar
Jim Blandy committed
259
static int
260
readchar (readcharfun, multibyte)
Jim Blandy's avatar
Jim Blandy committed
261
     Lisp_Object readcharfun;
262
     int *multibyte;
Jim Blandy's avatar
Jim Blandy committed
263 264
{
  Lisp_Object tem;
265
  register int c;
Kenichi Handa's avatar
Kenichi Handa committed
266 267 268 269
  int (*readbyte) P_ ((int, Lisp_Object));
  unsigned char buf[MAX_MULTIBYTE_LENGTH];
  int i, len;
  int emacs_mule_encoding = 0;
Jim Blandy's avatar
Jim Blandy committed
270

271 272 273
  if (multibyte)
    *multibyte = 0;

274
  readchar_count++;
275

276
  if (BUFFERP (readcharfun))
Jim Blandy's avatar
Jim Blandy committed
277
    {
278
      register struct buffer *inbuffer = XBUFFER (readcharfun);
Jim Blandy's avatar
Jim Blandy committed
279

280
      int pt_byte = BUF_PT_BYTE (inbuffer);
281

282 283
      if (pt_byte >= BUF_ZV_BYTE (inbuffer))
	return -1;
Jim Blandy's avatar
Jim Blandy committed
284

285 286
      if (! NILP (inbuffer->enable_multibyte_characters))
	{
287
	  /* Fetch the character code from the buffer.  */
288 289 290
	  unsigned char *p = BUF_BYTE_ADDRESS (inbuffer, pt_byte);
	  BUF_INC_POS (inbuffer, pt_byte);
	  c = STRING_CHAR (p, pt_byte - orig_pt_byte);
291 292
	  if (multibyte)
	    *multibyte = 1;
293 294 295 296
	}
      else
	{
	  c = BUF_FETCH_BYTE (inbuffer, pt_byte);
Kenichi Handa's avatar
Kenichi Handa committed
297 298
	  if (! ASCII_BYTE_P (c))
	    c = BYTE8_TO_CHAR (c);
299
	  pt_byte++;
300
	}
301
      SET_BUF_PT_BOTH (inbuffer, BUF_PT (inbuffer) + 1, pt_byte);
302

303
      return c;
Jim Blandy's avatar
Jim Blandy committed
304
    }
305
  if (MARKERP (readcharfun))
Jim Blandy's avatar
Jim Blandy committed
306
    {
307
      register struct buffer *inbuffer = XMARKER (readcharfun)->buffer;
Jim Blandy's avatar
Jim Blandy committed
308

309
      int bytepos = marker_byte_position (readcharfun);
310

311 312
      if (bytepos >= BUF_ZV_BYTE (inbuffer))
	return -1;
313

314 315
      if (! NILP (inbuffer->enable_multibyte_characters))
	{
316
	  /* Fetch the character code from the buffer.  */
317 318 319
	  unsigned char *p = BUF_BYTE_ADDRESS (inbuffer, bytepos);
	  BUF_INC_POS (inbuffer, bytepos);
	  c = STRING_CHAR (p, bytepos - orig_bytepos);
320 321
	  if (multibyte)
	    *multibyte = 1;
322 323 324 325
	}
      else
	{
	  c = BUF_FETCH_BYTE (inbuffer, bytepos);
Kenichi Handa's avatar
Kenichi Handa committed
326 327
	  if (! ASCII_BYTE_P (c))
	    c = BYTE8_TO_CHAR (c);
328
	  bytepos++;
329 330
	}

331 332 333 334
      XMARKER (readcharfun)->bytepos = bytepos;
      XMARKER (readcharfun)->charpos++;

      return c;
Jim Blandy's avatar
Jim Blandy committed
335
    }
336 337

  if (EQ (readcharfun, Qlambda))
Kenichi Handa's avatar
Kenichi Handa committed
338 339 340 341
    {
      readbyte = readbyte_for_lambda;
      goto read_multibyte;
    }
342

Jim Blandy's avatar
Jim Blandy committed
343
  if (EQ (readcharfun, Qget_file_char))
344
    {
Kenichi Handa's avatar
Kenichi Handa committed
345 346
      readbyte = readbyte_from_file;
      goto read_multibyte;
347
    }
Jim Blandy's avatar
Jim Blandy committed
348

349
  if (STRINGP (readcharfun))
Jim Blandy's avatar
Jim Blandy committed
350
    {
351
      if (read_from_string_index >= read_from_string_limit)
Jim Blandy's avatar
Jim Blandy committed
352
	c = -1;
353 354 355 356 357 358 359 360
      else if (STRING_MULTIBYTE (readcharfun))
	{
	  if (multibyte)
	    *multibyte = 1;
	  FETCH_STRING_CHAR_ADVANCE_NO_CHECK (c, readcharfun,
					      read_from_string_index,
					      read_from_string_index_byte);
	}
361
      else
362 363 364 365 366
	{
	  c = SREF (readcharfun, read_from_string_index_byte);
	  read_from_string_index++;
	  read_from_string_index_byte++;
	}
Jim Blandy's avatar
Jim Blandy committed
367 368 369
      return c;
    }

Kenichi Handa's avatar
Kenichi Handa committed
370 371 372 373 374 375 376 377 378 379 380 381
  if (CONSP (readcharfun))
    {
      /* This is the case that read_vector is reading from a unibyte
	 string that contains a byte sequence previously skipped
	 because of #@NUMBER.  The car part of readcharfun is that
	 string, and the cdr part is a value of readcharfun given to
	 read_vector.  */
      readbyte = readbyte_from_string;
      if (EQ (XCDR (readcharfun), Qget_emacs_mule_file_char))
	emacs_mule_encoding = 1;
      goto read_multibyte;
    }
Kenichi Handa's avatar
Kenichi Handa committed
382

Kenichi Handa's avatar
Kenichi Handa committed
383 384 385 386 387 388
  if (EQ (readcharfun, Qget_emacs_mule_file_char))
    {
      readbyte = readbyte_from_file;
      emacs_mule_encoding = 1;
      goto read_multibyte;
    }
Jim Blandy's avatar
Jim Blandy committed
389 390 391

  tem = call0 (readcharfun);

Jim Blandy's avatar
Jim Blandy committed
392
  if (NILP (tem))
Jim Blandy's avatar
Jim Blandy committed
393 394
    return -1;
  return XINT (tem);
Kenichi Handa's avatar
Kenichi Handa committed
395 396 397 398 399 400 401 402 403

 read_multibyte:
  if (unread_char >= 0)
    {
      c = unread_char;
      unread_char = -1;
      return c;
    }
  c = (*readbyte) (-1, readcharfun);
404 405 406 407 408
  if (c < 0 || load_each_byte)
    return c;
  if (multibyte)
    *multibyte = 1;
  if (ASCII_BYTE_P (c))
Kenichi Handa's avatar
Kenichi Handa committed
409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426
    return c;
  if (emacs_mule_encoding)
    return read_emacs_mule_char (c, readbyte, readcharfun);
  i = 0;
  buf[i++] = c;
  len = BYTES_BY_CHAR_HEAD (c);
  while (i < len)
    {
      c = (*readbyte) (-1, readcharfun);
      if (c < 0 || ! TRAILING_CODE_P (c))
	{
	  while (--i > 1)
	    (*readbyte) (buf[i], readcharfun);
	  return BYTE8_TO_CHAR (buf[0]);
	}
      buf[i++] = c;
    }
  return STRING_CHAR (buf, i);
Jim Blandy's avatar
Jim Blandy committed
427 428 429 430 431 432 433 434 435 436
}

/* Unread the character C in the way appropriate for the stream READCHARFUN.
   If the stream is a user function, call it with the char as argument.  */

static void
unreadchar (readcharfun, c)
     Lisp_Object readcharfun;
     int c;
{
437
  readchar_count--;
438 439 440 441
  if (c == -1)
    /* Don't back up the pointer if we're unreading the end-of-input mark,
       since readchar didn't advance it when we read it.  */
    ;
442
  else if (BUFFERP (readcharfun))
443
    {
444 445
      struct buffer *b = XBUFFER (readcharfun);
      int bytepos = BUF_PT_BYTE (b);
446

Kenichi Handa's avatar
Kenichi Handa committed
447 448 449
      BUF_PT (b)--;
      if (! NILP (b->enable_multibyte_characters))
	BUF_DEC_POS (b, bytepos);
450
      else
Kenichi Handa's avatar
Kenichi Handa committed
451
	bytepos--;
452

Kenichi Handa's avatar
Kenichi Handa committed
453
      BUF_PT_BYTE (b) = bytepos;
454
    }
455
  else if (MARKERP (readcharfun))
456
    {
457 458
      struct buffer *b = XMARKER (readcharfun)->buffer;
      int bytepos = XMARKER (readcharfun)->bytepos;
459

Kenichi Handa's avatar
Kenichi Handa committed
460 461 462
      XMARKER (readcharfun)->charpos--;
      if (! NILP (b->enable_multibyte_characters))
	BUF_DEC_POS (b, bytepos);
463
      else
Kenichi Handa's avatar
Kenichi Handa committed
464
	bytepos--;
465

Kenichi Handa's avatar
Kenichi Handa committed
466
      XMARKER (readcharfun)->bytepos = bytepos;
467
    }
468
  else if (STRINGP (readcharfun))
469 470 471 472 473
    {
      read_from_string_index--;
      read_from_string_index_byte
	= string_char_to_byte (readcharfun, read_from_string_index);
    }
Kenichi Handa's avatar
Kenichi Handa committed
474 475 476 477
  else if (CONSP (readcharfun))
    {
      unread_char = c;
    }
478
  else if (EQ (readcharfun, Qlambda))
Kenichi Handa's avatar
Kenichi Handa committed
479 480 481 482 483 484 485
    {
      unread_char = c;
    }
  else if (EQ (readcharfun, Qget_file_char)
	   || EQ (readcharfun, Qget_emacs_mule_file_char))
    {
      if (load_each_byte)
Miles Bader's avatar
Miles Bader committed
486 487 488 489 490
	{
	  BLOCK_INPUT;
	  ungetc (c, instream);
	  UNBLOCK_INPUT;
	}
Kenichi Handa's avatar
Kenichi Handa committed
491 492 493
      else
	unread_char = c;
    }
Jim Blandy's avatar
Jim Blandy committed
494 495 496 497
  else
    call1 (readcharfun, make_number (c));
}

Kenichi Handa's avatar
Kenichi Handa committed
498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513
static int
readbyte_for_lambda (c, readcharfun)
     int c;
     Lisp_Object readcharfun;
{
  return read_bytecode_char (c >= 0);
}


static int
readbyte_from_file (c, readcharfun)
     int c;
     Lisp_Object readcharfun;
{
  if (c >= 0)
    {
YAMAMOTO Mitsuharu's avatar
YAMAMOTO Mitsuharu committed
514
      BLOCK_INPUT;
Kenichi Handa's avatar
Kenichi Handa committed
515
      ungetc (c, instream);
YAMAMOTO Mitsuharu's avatar
YAMAMOTO Mitsuharu committed
516
      UNBLOCK_INPUT;
Kenichi Handa's avatar
Kenichi Handa committed
517 518 519
      return 0;
    }

Miles Bader's avatar
Miles Bader committed
520
  BLOCK_INPUT;
Kenichi Handa's avatar
Kenichi Handa committed
521
  c = getc (instream);
Miles Bader's avatar
Miles Bader committed
522

Kenichi Handa's avatar
Kenichi Handa committed
523
#ifdef EINTR
Miles Bader's avatar
Miles Bader committed
524 525 526
  /* Interrupted reads have been observed while reading over the network */
  while (c == EOF && ferror (instream) && errno == EINTR)
    {
Miles Bader's avatar
Miles Bader committed
527
      UNBLOCK_INPUT;
Miles Bader's avatar
Miles Bader committed
528 529
      QUIT;
      BLOCK_INPUT;
Miles Bader's avatar
Miles Bader committed
530
      clearerr (instream);
Miles Bader's avatar
Miles Bader committed
531
      c = getc (instream);
YAMAMOTO Mitsuharu's avatar
YAMAMOTO Mitsuharu committed
532
    }
Kenichi Handa's avatar
Kenichi Handa committed
533
#endif
Miles Bader's avatar
Miles Bader committed
534

Miles Bader's avatar
Miles Bader committed
535 536
  UNBLOCK_INPUT;

Kenichi Handa's avatar
Kenichi Handa committed
537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552
  return (c == EOF ? -1 : c);
}

static int
readbyte_from_string (c, readcharfun)
     int c;
     Lisp_Object readcharfun;
{
  Lisp_Object string = XCAR (readcharfun);

  if (c >= 0)
    {
      read_from_string_index--;
      read_from_string_index_byte
	= string_char_to_byte (string, read_from_string_index);
    }
Kenichi Handa's avatar
Kenichi Handa committed
553

Kenichi Handa's avatar
Kenichi Handa committed
554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602
  if (read_from_string_index >= read_from_string_limit)
    c = -1;
  else
    FETCH_STRING_CHAR_ADVANCE (c, string,
			       read_from_string_index,
			       read_from_string_index_byte);
  return c;
}


/* Read one non-ASCII character from INSTREAM.  The character is
   encoded in `emacs-mule' and the first byte is already read in
   C.  */

extern char emacs_mule_bytes[256];

static int
read_emacs_mule_char (c, readbyte, readcharfun)
     int c;
     int (*readbyte) P_ ((int, Lisp_Object));
     Lisp_Object readcharfun;
{
  /* Emacs-mule coding uses at most 4-byte for one character.  */
  unsigned char buf[4];
  int len = emacs_mule_bytes[c];
  struct charset *charset;
  int i;
  unsigned code;

  if (len == 1)
    /* C is not a valid leading-code of `emacs-mule'.  */
    return BYTE8_TO_CHAR (c);

  i = 0;
  buf[i++] = c;
  while (i < len)
    {
      c = (*readbyte) (-1, readcharfun);
      if (c < 0xA0)
	{
	  while (--i > 1)
	    (*readbyte) (buf[i], readcharfun);
	  return BYTE8_TO_CHAR (buf[0]);
	}
      buf[i++] = c;
    }

  if (len == 2)
    {
Dave Love's avatar
Dave Love committed
603
      charset = emacs_mule_charset[buf[0]];
Kenichi Handa's avatar
Kenichi Handa committed
604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622
      code = buf[1] & 0x7F;
    }
  else if (len == 3)
    {
      if (buf[0] == EMACS_MULE_LEADING_CODE_PRIVATE_11
	  || buf[0] == EMACS_MULE_LEADING_CODE_PRIVATE_12)
	{
	  charset = emacs_mule_charset[buf[1]];
	  code = buf[2] & 0x7F;
	}
      else
	{
	  charset = emacs_mule_charset[buf[0]];
	  code = ((buf[1] << 8) | buf[2]) & 0x7F7F;
	}
    }
  else
    {
      charset = emacs_mule_charset[buf[1]];
Kenichi Handa's avatar
Kenichi Handa committed
623
      code = ((buf[2] << 8) | buf[3]) & 0x7F7F;
Kenichi Handa's avatar
Kenichi Handa committed
624 625 626 627 628 629 630 631 632
    }
  c = DECODE_CHAR (charset, code);
  if (c < 0)
    Fsignal (Qinvalid_read_syntax,
	     Fcons (build_string ("invalid multibyte form"), Qnil));
  return c;
}


633 634 635
static Lisp_Object read_internal_start P_ ((Lisp_Object, Lisp_Object,
					    Lisp_Object));
static Lisp_Object read0 P_ ((Lisp_Object));
636
static Lisp_Object read1 P_ ((Lisp_Object, int *, int));
637 638 639 640 641 642 643 644 645

static Lisp_Object read_list P_ ((int, Lisp_Object));
static Lisp_Object read_vector P_ ((Lisp_Object, int));

static Lisp_Object substitute_object_recurse P_ ((Lisp_Object, Lisp_Object,
						  Lisp_Object));
static void substitute_object_in_subtree P_ ((Lisp_Object,
					      Lisp_Object));
static void substitute_in_interval P_ ((INTERVAL, Lisp_Object));
646

Jim Blandy's avatar
Jim Blandy committed
647

648
/* Get a character from the tty.  */
Jim Blandy's avatar
Jim Blandy committed
649

650 651 652 653 654 655 656 657 658 659 660 661 662
/* Read input events until we get one that's acceptable for our purposes.

   If NO_SWITCH_FRAME is non-zero, switch-frame events are stashed
   until we get a character we like, and then stuffed into
   unread_switch_frame.

   If ASCII_REQUIRED is non-zero, we check function key events to see
   if the unmodified version of the symbol has a Qascii_character
   property, and use that character, if present.

   If ERROR_NONASCII is non-zero, we signal an error if the input we
   get isn't an ASCII character with modifiers.  If it's zero but
   ASCII_REQUIRED is non-zero, we just re-read until we get an ASCII
663 664 665
   character.

   If INPUT_METHOD is nonzero, we invoke the current input method
666 667 668 669
   if the character warrants that.

   If SECONDS is a number, we wait that many seconds for input, and
   return Qnil if no input arrives within that time.  */
670

671
Lisp_Object
672
read_filtered_event (no_switch_frame, ascii_required, error_nonascii,
673
		     input_method, seconds)
674
     int no_switch_frame, ascii_required, error_nonascii, input_method;
675
     Lisp_Object seconds;
676
{
677
  Lisp_Object val, delayed_switch_frame;
678
  EMACS_TIME end_time;
679

680
#ifdef HAVE_WINDOW_SYSTEM
681 682
  if (display_hourglass_p)
    cancel_hourglass ();
683
#endif
684

685
  delayed_switch_frame = Qnil;
686

687 688 689 690 691
  /* Compute timeout.  */
  if (NUMBERP (seconds))
    {
      EMACS_TIME wait_time;
      int sec, usec;
692
      double duration = extract_float (seconds);
693 694 695 696 697 698 699 700

      sec  = (int) duration;
      usec = (duration - sec) * 1000000;
      EMACS_GET_TIME (end_time);
      EMACS_SET_SECS_USECS (wait_time, sec, usec);
      EMACS_ADD_TIME (end_time, end_time, wait_time);
    }

Karoly Lorentey's avatar
Karoly Lorentey committed
701
/* Read until we get an acceptable event.  */
702
 retry:
703
  do
Karoly Lorentey's avatar
Karoly Lorentey committed
704 705
    val = read_char (0, 0, 0, (input_method ? Qnil : Qt), 0,
		     NUMBERP (seconds) ? &end_time : NULL);
706
  while (INTEGERP (val) && XINT (val) == -2); /* wrong_kboard_jmpbuf */
707

708
  if (BUFFERP (val))
709 710
    goto retry;

711
  /* switch-frame events are put off until after the next ASCII
Karl Heuer's avatar
Karl Heuer committed
712
     character.  This is better than signaling an error just because
713 714 715 716 717
     the last characters were typed to a separate minibuffer frame,
     for example.  Eventually, some code which can deal with
     switch-frame events will read it and process it.  */
  if (no_switch_frame
      && EVENT_HAS_PARAMETERS (val)
718
      && EQ (EVENT_HEAD_KIND (EVENT_HEAD (val)), Qswitch_frame))
719 720 721 722 723
    {
      delayed_switch_frame = val;
      goto retry;
    }

724
  if (ascii_required && !(NUMBERP (seconds) && NILP (val)))
725 726
    {
      /* Convert certain symbols to their ASCII equivalents.  */
727
      if (SYMBOLP (val))
728
	{
729
	  Lisp_Object tem, tem1;
730 731 732 733 734 735 736
	  tem = Fget (val, Qevent_symbol_element_mask);
	  if (!NILP (tem))
	    {
	      tem1 = Fget (Fcar (tem), Qascii_character);
	      /* Merge this symbol's modifier bits
		 with the ASCII equivalent of its basic code.  */
	      if (!NILP (tem1))
737
		XSETFASTINT (val, XINT (tem1) | XINT (Fcar (Fcdr (tem))));
738 739
	    }
	}
740

741
      /* If we don't have a character now, deal with it appropriately.  */
742
      if (!INTEGERP (val))
743 744 745
	{
	  if (error_nonascii)
	    {
746
	      Vunread_command_events = Fcons (val, Qnil);
747 748 749 750 751 752 753 754 755 756
	      error ("Non-character input-event");
	    }
	  else
	    goto retry;
	}
    }

  if (! NILP (delayed_switch_frame))
    unread_switch_frame = delayed_switch_frame;

757 758
#if 0

759
#ifdef HAVE_WINDOW_SYSTEM
760 761
  if (display_hourglass_p)
    start_hourglass ();
762
#endif
763 764 765

#endif

766 767 768
  return val;
}

769
DEFUN ("read-char", Fread_char, Sread_char, 0, 3, 0,
770 771
       doc: /* Read a character from the command input (keyboard or macro).
It is returned as a number.
772 773 774
If the character has modifiers, they are resolved and reflected to the
character code if possible (e.g. C-SPC -> 0).

775 776
If the user generates an event which is not a character (i.e. a mouse
click or function key event), `read-char' signals an error.  As an
777 778
exception, switch-frame events are put off until non-character events
can be read.
779 780 781 782 783 784
If you want to read non-character events, or ignore them, call
`read-event' or `read-char-exclusive' instead.

If the optional argument PROMPT is non-nil, display that as a prompt.
If the optional argument INHERIT-INPUT-METHOD is non-nil and some
input method is turned on in the current buffer, that input method
785 786 787 788 789 790 791
is used for reading a character.
If the optional argument SECONDS is non-nil, it should be a number
specifying the maximum number of seconds to wait for input.  If no
input arrives in that time, return nil.  SECONDS may be a
floating-point value.  */)
     (prompt, inherit_input_method, seconds)
     Lisp_Object prompt, inherit_input_method, seconds;
Jim Blandy's avatar
Jim Blandy committed
792
{
793 794
  Lisp_Object val;

795 796
  if (! NILP (prompt))
    message_with_string ("%s", prompt, 0);
797
  val = read_filtered_event (1, 1, 1, ! NILP (inherit_input_method), seconds);
798 799 800

  return (NILP (val) ? Qnil
	  : make_number (char_resolve_modifier_mask (XINT (val))));
Jim Blandy's avatar
Jim Blandy committed
801 802
}

803
DEFUN ("read-event", Fread_event, Sread_event, 0, 3, 0,
804 805 806 807
       doc: /* Read an event object from the input stream.
If the optional argument PROMPT is non-nil, display that as a prompt.
If the optional argument INHERIT-INPUT-METHOD is non-nil and some
input method is turned on in the current buffer, that input method
808 809 810 811 812 813 814
is used for reading a character.
If the optional argument SECONDS is non-nil, it should be a number
specifying the maximum number of seconds to wait for input.  If no
input arrives in that time, return nil.  SECONDS may be a
floating-point value.  */)
     (prompt, inherit_input_method, seconds)
     Lisp_Object prompt, inherit_input_method, seconds;
Jim Blandy's avatar
Jim Blandy committed
815
{
816 817
  if (! NILP (prompt))
    message_with_string ("%s", prompt, 0);
818
  return read_filtered_event (0, 0, 0, ! NILP (inherit_input_method), seconds);
Jim Blandy's avatar
Jim Blandy committed
819 820
}

821
DEFUN ("read-char-exclusive", Fread_char_exclusive, Sread_char_exclusive, 0, 3, 0,
822 823
       doc: /* Read a character from the command input (keyboard or macro).
It is returned as a number.  Non-character events are ignored.
824 825
If the character has modifiers, they are resolved and reflected to the
character code if possible (e.g. C-SPC -> 0).
826 827 828 829

If the optional argument PROMPT is non-nil, display that as a prompt.
If the optional argument INHERIT-INPUT-METHOD is non-nil and some
input method is turned on in the current buffer, that input method
830 831 832 833 834 835 836
is used for reading a character.
If the optional argument SECONDS is non-nil, it should be a number
specifying the maximum number of seconds to wait for input.  If no
input arrives in that time, return nil.  SECONDS may be a
floating-point value.  */)
     (prompt, inherit_input_method, seconds)
     Lisp_Object prompt, inherit_input_method, seconds;
Jim Blandy's avatar
Jim Blandy committed
837
{
838 839
  Lisp_Object val;

840 841
  if (! NILP (prompt))
    message_with_string ("%s", prompt, 0);
842

843
  val = read_filtered_event (1, 1, 0, ! NILP (inherit_input_method), seconds);
844 845 846

  return (NILP (val) ? Qnil
	  : make_number (char_resolve_modifier_mask (XINT (val))));
Jim Blandy's avatar
Jim Blandy committed
847 848 849
}

DEFUN ("get-file-char", Fget_file_char, Sget_file_char, 0, 0, 0,
850 851
       doc: /* Don't use this yourself.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
852 853
{
  register Lisp_Object val;
YAMAMOTO Mitsuharu's avatar
YAMAMOTO Mitsuharu committed
854
  BLOCK_INPUT;
855
  XSETINT (val, getc (instream));
YAMAMOTO Mitsuharu's avatar
YAMAMOTO Mitsuharu committed
856
  UNBLOCK_INPUT;
Jim Blandy's avatar
Jim Blandy committed
857 858
  return val;
}
859 860


861

Kenichi Handa's avatar
Kenichi Handa committed
862
/* Value is a version number of byte compiled code if the file
Miles Bader's avatar
Miles Bader committed
863
   associated with file descriptor FD is a compiled Lisp file that's
Kenichi Handa's avatar
Kenichi Handa committed
864 865 866
   safe to load.  Only files compiled with Emacs are safe to load.
   Files compiled with XEmacs can lead to a crash in Fbyte_code
   because of an incompatible change in the byte compiler.  */
867 868 869 870 871 872 873 874

static int
safe_to_load_p (fd)
     int fd;
{
  char buf[512];
  int nbytes, i;
  int safe_p = 1;
Kenichi Handa's avatar
Kenichi Handa committed
875
  int version = 1;
876 877 878 879 880 881 882 883 884

  /* Read the first few bytes from the file, and look for a line
     specifying the byte compiler version used.  */
  nbytes = emacs_read (fd, buf, sizeof buf - 1);
  if (nbytes > 0)
    {
      buf[nbytes] = '\0';

      /* Skip to the next newline, skipping over the initial `ELC'
Dave Love's avatar
Dave Love committed
885
	 with NUL bytes following it, but note the version.  */
886
      for (i = 0; i < nbytes && buf[i] != '\n'; ++i)
Dave Love's avatar
Dave Love committed
887
	if (i == 4)
Kenichi Handa's avatar
Kenichi Handa committed
888
	  version = buf[i];
889

890 891
      if (i == nbytes
	  || fast_c_string_match_ignore_case (Vbytecomp_version_regexp,
892 893 894
					      buf + i) < 0)
	safe_p = 0;
    }
Dave Love's avatar
Dave Love committed
895 896
  if (safe_p)
    safe_p = version;
897 898 899 900 901 902

  lseek (fd, 0, SEEK_SET);
  return safe_p;
}


903 904 905 906 907 908 909 910 911 912
/* Callback for record_unwind_protect.  Restore the old load list OLD,
   after loading a file successfully.  */

static Lisp_Object
record_load_unwind (old)
     Lisp_Object old;
{
  return Vloads_in_progress = old;
}

913 914 915 916 917 918 919 920
/* This handler function is used via internal_condition_case_1.  */

static Lisp_Object
load_error_handler (data)
     Lisp_Object data;
{
  return Qnil;
}
921

922 923 924 925 926 927
static Lisp_Object
load_warn_old_style_backquotes (file)
     Lisp_Object file;
{
  if (!NILP (Vold_style_backquotes))
    {
928
      Lisp_Object args[2];
929
      args[0] = build_string ("Loading `%s': old-style backquotes detected!");
930 931 932 933 934 935
      args[1] = file;
      Fmessage (2, args);
    }
  return Qnil;
}

936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957
DEFUN ("get-load-suffixes", Fget_load_suffixes, Sget_load_suffixes, 0, 0, 0,
       doc: /* Return the suffixes that `load' should try if a suffix is \
required.
This uses the variables `load-suffixes' and `load-file-rep-suffixes'.  */)
     ()
{
  Lisp_Object lst = Qnil, suffixes = Vload_suffixes, suffix, ext;
  while (CONSP (suffixes))
    {
      Lisp_Object exts = Vload_file_rep_suffixes;
      suffix = XCAR (suffixes);
      suffixes = XCDR (suffixes);
      while (CONSP (exts))
	{
	  ext = XCAR (exts);
	  exts = XCDR (exts);
	  lst = Fcons (concat2 (suffix, ext), lst);
	}
    }
  return Fnreverse (lst);
}

958
DEFUN ("load", Fload, Sload, 1, 5, 0,
959 960
       doc: /* Execute a file of Lisp code named FILE.
First try FILE with `.elc' appended, then try with `.el',
961
then try FILE unmodified (the exact suffixes in the exact order are
962
determined by `load-suffixes').  Environment variable references in
963
FILE are replaced with their values by calling `substitute-in-file-name'.
964
This function searches the directories in `load-path'.
965

966
If optional second arg NOERROR is non-nil,
967
report no error if FILE doesn't exist.
968
Print messages at start and end of loading unless
969
optional third arg NOMESSAGE is non-nil.
970
If optional fourth arg NOSUFFIX is non-nil, don't try adding
971
suffixes `.elc' or `.el' to the specified name FILE.
972
If optional fifth arg MUST-SUFFIX is non-nil, insist on
973 974 975 976 977 978 979 980 981 982 983 984 985 986 987
the suffix `.elc' or `.el'; don't accept just FILE unless
it ends in one of those suffixes or includes a directory name.

If this function fails to find a file, it may look for different
representations of that file before trying another file.
It does so by adding the non-empty suffixes in `load-file-rep-suffixes'
to the file name.  Emacs uses this feature mainly to find compressed
versions of files when Auto Compression mode is enabled.

The exact suffixes that this function tries out, in the exact order,
are given by the value of the variable `load-file-rep-suffixes' if
NOSUFFIX is non-nil and by the return value of the function
`get-load-suffixes' if MUST-SUFFIX is non-nil.  If both NOSUFFIX and
MUST-SUFFIX are nil, this function first tries out the latter suffixes
and then the former.
988 989 990 991 992

Loading a file records its definitions, and its `provide' and
`require' calls, in an element of `load-history' whose
car is the file name loaded.  See `load-history'.

993
Return t if the file exists and loads successfully.  */)
994
     (file, noerror, nomessage, nosuffix, must_suffix)
995
     Lisp_Object file, noerror, nomessage, nosuffix, must_suffix;
Jim Blandy's avatar
Jim Blandy committed
996 997 998
{
  register FILE *stream;
  register int fd = -1;
Juanma Barranquero's avatar
Juanma Barranquero committed
999
  int count = SPECPDL_INDEX ();
1000 1001
  struct gcpro gcpro1, gcpro2, gcpro3;
  Lisp_Object found, efound, hist_file_name;
1002 1003 1004 1005
  /* 1 means we printed the ".el is newer" message.  */
  int newer = 0;
  /* 1 means we are loading a compiled file.  */
  int compiled = 0;
1006
  Lisp_Object handler;
1007
  int safe_p = 1;
1008
  char *fmode = "r";
1009
  Lisp_Object tmp[2];
Kenichi Handa's avatar
Kenichi Handa committed
1010 1011
  int version;

1012
#ifdef DOS_NT
1013
  fmode = "rt";
1014
#endif /* DOS_NT */