fileio.c 85.5 KB
Newer Older
Jim Blandy's avatar
Jim Blandy committed
1
/* File IO for GNU Emacs.
Jim Blandy's avatar
Jim Blandy committed
2
   Copyright (C) 1985, 1986, 1987, 1988, 1992 Free Software Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
3 4 5 6 7

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
Jim Blandy's avatar
Jim Blandy committed
8
the Free Software Foundation; either version 2, or (at your option)
Jim Blandy's avatar
Jim Blandy committed
9 10 11 12 13 14 15 16 17 18 19
any later version.

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

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

Jim Blandy's avatar
Jim Blandy committed
20
#include "config.h"
Jim Blandy's avatar
Jim Blandy committed
21 22 23

#include <sys/types.h>
#include <sys/stat.h>
Jim Blandy's avatar
Jim Blandy committed
24 25

#ifdef VMS
Jim Blandy's avatar
Jim Blandy committed
26
#include "vms-pwd.h"
Jim Blandy's avatar
Jim Blandy committed
27
#else
Jim Blandy's avatar
Jim Blandy committed
28
#include <pwd.h>
Jim Blandy's avatar
Jim Blandy committed
29 30
#endif

Jim Blandy's avatar
Jim Blandy committed
31
#include <ctype.h>
Jim Blandy's avatar
Jim Blandy committed
32 33 34 35 36 37 38

#ifdef VMS
#include "dir.h"
#include <perror.h>
#include <stddef.h>
#include <string.h>
#else
Jim Blandy's avatar
Jim Blandy committed
39
#include <sys/dir.h>
Jim Blandy's avatar
Jim Blandy committed
40 41
#endif

Jim Blandy's avatar
Jim Blandy committed
42 43
#include <errno.h>

Jim Blandy's avatar
Jim Blandy committed
44
#ifndef vax11c
Jim Blandy's avatar
Jim Blandy committed
45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66
extern int errno;
extern char *sys_errlist[];
extern int sys_nerr;
#endif

#define err_str(a) ((a) < sys_nerr ? sys_errlist[a] : "unknown error")

#ifdef APOLLO
#include <sys/time.h>
#endif

#include "lisp.h"
#include "buffer.h"
#include "window.h"

#ifdef VMS
#include <file.h>
#include <rmsdef.h>
#include <fab.h>
#include <nam.h>
#endif

Jim Blandy's avatar
Jim Blandy committed
67
#include "systime.h"
Jim Blandy's avatar
Jim Blandy committed
68 69 70

#ifdef HPUX
#include <netio.h>
Jim Blandy's avatar
Jim Blandy committed
71
#ifndef HPUX8
Jim Blandy's avatar
Jim Blandy committed
72 73
#include <errnet.h>
#endif
Jim Blandy's avatar
Jim Blandy committed
74
#endif
Jim Blandy's avatar
Jim Blandy committed
75 76 77 78 79 80 81 82 83 84 85 86 87 88 89

#ifndef O_WRONLY
#define O_WRONLY 1
#endif

#define min(a, b) ((a) < (b) ? (a) : (b))
#define max(a, b) ((a) > (b) ? (a) : (b))

/* Nonzero during writing of auto-save files */
int auto_saving;

/* Set by auto_save_1 to mode of original file so Fwrite_region will create
   a new file with the same mode as the original */
int auto_save_mode_bits;

90 91 92 93
/* Alist of elements (REGEXP . HANDLER) for file names 
   whose I/O is done with a special handler.  */
Lisp_Object Vfile_name_handler_alist;

Jim Blandy's avatar
Jim Blandy committed
94 95 96 97 98 99 100 101 102 103
/* Nonzero means, when reading a filename in the minibuffer,
 start out by inserting the default directory into the minibuffer. */
int insert_default_directory;

/* On VMS, nonzero means write new files with record format stmlf.
   Zero means use var format.  */
int vms_stmlf_recfm;

Lisp_Object Qfile_error, Qfile_already_exists;

104 105
Lisp_Object Qfile_name_history;

Jim Blandy's avatar
Jim Blandy committed
106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125
report_file_error (string, data)
     char *string;
     Lisp_Object data;
{
  Lisp_Object errstring;

  if (errno >= 0 && errno < sys_nerr)
    errstring = build_string (sys_errlist[errno]);
  else
    errstring = build_string ("undocumented error code");

  /* System error messages are capitalized.  Downcase the initial
     unless it is followed by a slash.  */
  if (XSTRING (errstring)->data[1] != '/')
    XSTRING (errstring)->data[0] = DOWNCASE (XSTRING (errstring)->data[0]);

  while (1)
    Fsignal (Qfile_error,
	     Fcons (build_string (string), Fcons (errstring, data)));
}
126 127 128 129 130 131

close_file_unwind (fd)
     Lisp_Object fd;
{
  close (XFASTINT (fd));
}
Jim Blandy's avatar
Jim Blandy committed
132

133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161
Lisp_Object Qcopy_file;
Lisp_Object Qmake_directory;
Lisp_Object Qdelete_directory;
Lisp_Object Qdelete_file;
Lisp_Object Qrename_file;
Lisp_Object Qadd_name_to_file;
Lisp_Object Qmake_symbolic_link;
Lisp_Object Qfile_exists_p;
Lisp_Object Qfile_executable_p;
Lisp_Object Qfile_readable_p;
Lisp_Object Qfile_symlink_p;
Lisp_Object Qfile_writable_p;
Lisp_Object Qfile_directory_p;
Lisp_Object Qfile_accessible_directory_p;
Lisp_Object Qfile_modes;
Lisp_Object Qset_file_modes;
Lisp_Object Qfile_newer_than_file_p;
Lisp_Object Qinsert_file_contents;
Lisp_Object Qwrite_region;
Lisp_Object Qverify_visited_file_modtime;

/* If FILENAME is handled specially on account of its syntax,
   return its handler function.  Otherwise, return nil.  */

Lisp_Object
find_file_handler (filename)
     Lisp_Object filename;
{
  Lisp_Object chain;
Jim Blandy's avatar
Jim Blandy committed
162
  for (chain = Vfile_name_handler_alist; XTYPE (chain) == Lisp_Cons;
163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178
       chain = XCONS (chain)->cdr)
    {
      Lisp_Object elt;
      elt = XCONS (chain)->car;
      if (XTYPE (elt) == Lisp_Cons)
	{
	  Lisp_Object string;
	  string = XCONS (elt)->car;
	  if (XTYPE (string) == Lisp_String
	      && fast_string_match (string, filename))
	    return XCONS (elt)->cdr;
	}
    }
  return Qnil;
}

Jim Blandy's avatar
Jim Blandy committed
179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282
DEFUN ("file-name-directory", Ffile_name_directory, Sfile_name_directory,
  1, 1, 0,
  "Return the directory component in file name NAME.\n\
Return nil if NAME does not include a directory.\n\
Otherwise return a directory spec.\n\
Given a Unix syntax file name, returns a string ending in slash;\n\
on VMS, perhaps instead a string ending in `:', `]' or `>'.")
  (file)
     Lisp_Object file;
{
  register unsigned char *beg;
  register unsigned char *p;

  CHECK_STRING (file, 0);

  beg = XSTRING (file)->data;
  p = beg + XSTRING (file)->size;

  while (p != beg && p[-1] != '/'
#ifdef VMS
	 && p[-1] != ':' && p[-1] != ']' && p[-1] != '>'
#endif /* VMS */
	 ) p--;

  if (p == beg)
    return Qnil;
  return make_string (beg, p - beg);
}

DEFUN ("file-name-nondirectory", Ffile_name_nondirectory, Sfile_name_nondirectory,
  1, 1, 0,
  "Return file name NAME sans its directory.\n\
For example, in a Unix-syntax file name,\n\
this is everything after the last slash,\n\
or the entire name if it contains no slash.")
  (file)
     Lisp_Object file;
{
  register unsigned char *beg, *p, *end;

  CHECK_STRING (file, 0);

  beg = XSTRING (file)->data;
  end = p = beg + XSTRING (file)->size;

  while (p != beg && p[-1] != '/'
#ifdef VMS
	 && p[-1] != ':' && p[-1] != ']' && p[-1] != '>'
#endif /* VMS */
	 ) p--;

  return make_string (p, end - p);
}

char *
file_name_as_directory (out, in)
     char *out, *in;
{
  int size = strlen (in) - 1;

  strcpy (out, in);

#ifdef VMS
  /* Is it already a directory string? */
  if (in[size] == ':' || in[size] == ']' || in[size] == '>')
    return out;
  /* Is it a VMS directory file name?  If so, hack VMS syntax.  */
  else if (! index (in, '/')
	   && ((size > 3 && ! strcmp (&in[size - 3], ".DIR"))
	       || (size > 3 && ! strcmp (&in[size - 3], ".dir"))
	       || (size > 5 && (! strncmp (&in[size - 5], ".DIR", 4)
				|| ! strncmp (&in[size - 5], ".dir", 4))
		   && (in[size - 1] == '.' || in[size - 1] == ';')
		   && in[size] == '1')))
    {
      register char *p, *dot;
      char brack;

      /* x.dir -> [.x]
	 dir:x.dir --> dir:[x]
	 dir:[x]y.dir --> dir:[x.y] */
      p = in + size;
      while (p != in && *p != ':' && *p != '>' && *p != ']') p--;
      if (p != in)
	{
	  strncpy (out, in, p - in);
	  out[p - in] = '\0';
	  if (*p == ':')
	    {
	      brack = ']';
	      strcat (out, ":[");
	    }
	  else
	    {
	      brack = *p;
	      strcat (out, ".");
	    }
	  p++;
	}
      else
	{
	  brack = ']';
	  strcpy (out, "[.");
	}
Jim Blandy's avatar
Jim Blandy committed
283 284
      dot = index (p, '.');
      if (dot)
Jim Blandy's avatar
Jim Blandy committed
285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320
	{
	  /* blindly remove any extension */
	  size = strlen (out) + (dot - p);
	  strncat (out, p, dot - p);
	}
      else
	{
	  strcat (out, p);
	  size = strlen (out);
	}
      out[size++] = brack;
      out[size] = '\0';
    }
#else /* not VMS */
  /* For Unix syntax, Append a slash if necessary */
  if (out[size] != '/')
    strcat (out, "/");
#endif /* not VMS */
  return out;
}

DEFUN ("file-name-as-directory", Ffile_name_as_directory,
       Sfile_name_as_directory, 1, 1, 0,
  "Return a string representing file FILENAME interpreted as a directory.\n\
This operation exists because a directory is also a file, but its name as\n\
a directory is different from its name as a file.\n\
The result can be used as the value of `default-directory'\n\
or passed as second argument to `expand-file-name'.\n\
For a Unix-syntax file name, just appends a slash.\n\
On VMS, converts \"[X]FOO.DIR\" to \"[X.FOO]\", etc.")
  (file)
     Lisp_Object file;
{
  char *buf;

  CHECK_STRING (file, 0);
Jim Blandy's avatar
Jim Blandy committed
321
  if (NILP (file))
Jim Blandy's avatar
Jim Blandy committed
322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414
    return Qnil;
  buf = (char *) alloca (XSTRING (file)->size + 10);
  return build_string (file_name_as_directory (buf, XSTRING (file)->data));
}

/*
 * Convert from directory name to filename.
 * On VMS:
 *       xyzzy:[mukesh.emacs] => xyzzy:[mukesh]emacs.dir.1
 *       xyzzy:[mukesh] => xyzzy:[000000]mukesh.dir.1
 * On UNIX, it's simple: just make sure there is a terminating /

 * Value is nonzero if the string output is different from the input.
 */

directory_file_name (src, dst)
     char *src, *dst;
{
  long slen;
#ifdef VMS
  long rlen;
  char * ptr, * rptr;
  char bracket;
  struct FAB fab = cc$rms_fab;
  struct NAM nam = cc$rms_nam;
  char esa[NAM$C_MAXRSS];
#endif /* VMS */

  slen = strlen (src);
#ifdef VMS
  if (! index (src, '/')
      && (src[slen - 1] == ']'
	  || src[slen - 1] == ':'
	  || src[slen - 1] == '>'))
    {
      /* VMS style - convert [x.y.z] to [x.y]z, [x] to [000000]x */
      fab.fab$l_fna = src;
      fab.fab$b_fns = slen;
      fab.fab$l_nam = &nam;
      fab.fab$l_fop = FAB$M_NAM;

      nam.nam$l_esa = esa;
      nam.nam$b_ess = sizeof esa;
      nam.nam$b_nop |= NAM$M_SYNCHK;

      /* We call SYS$PARSE to handle such things as [--] for us. */
      if (SYS$PARSE(&fab, 0, 0) == RMS$_NORMAL)
	{
	  slen = nam.nam$b_esl;
	  if (esa[slen - 1] == ';' && esa[slen - 2] == '.')
	    slen -= 2;
	  esa[slen] = '\0';
	  src = esa;
	}
      if (src[slen - 1] != ']' && src[slen - 1] != '>')
	{
	  /* what about when we have logical_name:???? */
	  if (src[slen - 1] == ':')
	    {			/* Xlate logical name and see what we get */
	      ptr = strcpy (dst, src); /* upper case for getenv */
	      while (*ptr)
		{
		  if ('a' <= *ptr && *ptr <= 'z')
		    *ptr -= 040;
		  ptr++;
		}
	      dst[slen - 1] = 0;	/* remove colon */
	      if (!(src = egetenv (dst)))
		return 0;
	      /* should we jump to the beginning of this procedure?
		 Good points: allows us to use logical names that xlate
		 to Unix names,
		 Bad points: can be a problem if we just translated to a device
		 name...
		 For now, I'll punt and always expect VMS names, and hope for
		 the best! */
	      slen = strlen (src);
	      if (src[slen - 1] != ']' && src[slen - 1] != '>')
		{ /* no recursion here! */
		  strcpy (dst, src);
		  return 0;
		}
	    }
	  else
	    {		/* not a directory spec */
	      strcpy (dst, src);
	      return 0;
	    }
	}
      bracket = src[slen - 1];

      /* If bracket is ']' or '>', bracket - 2 is the corresponding
	 opening bracket.  */
Jim Blandy's avatar
Jim Blandy committed
415 416
      ptr = index (src, bracket - 2);
      if (ptr == 0)
Jim Blandy's avatar
Jim Blandy committed
417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465
	{ /* no opening bracket */
	  strcpy (dst, src);
	  return 0;
	}
      if (!(rptr = rindex (src, '.')))
	rptr = ptr;
      slen = rptr - src;
      strncpy (dst, src, slen);
      dst[slen] = '\0';
      if (*rptr == '.')
	{
	  dst[slen++] = bracket;
	  dst[slen] = '\0';
	}
      else
	{
	  /* If we have the top-level of a rooted directory (i.e. xx:[000000]),
	     then translate the device and recurse. */
	  if (dst[slen - 1] == ':'
	      && dst[slen - 2] != ':'	/* skip decnet nodes */
	      && strcmp(src + slen, "[000000]") == 0)
	    {
	      dst[slen - 1] = '\0';
	      if ((ptr = egetenv (dst))
		  && (rlen = strlen (ptr) - 1) > 0
		  && (ptr[rlen] == ']' || ptr[rlen] == '>')
		  && ptr[rlen - 1] == '.')
		{
		  ptr[rlen - 1] = ']';
		  ptr[rlen] = '\0';
		  return directory_file_name (ptr, dst);
		}
	      else
		dst[slen - 1] = ':';
	    }
	  strcat (dst, "[000000]");
	  slen += 8;
	}
      rptr++;
      rlen = strlen (rptr) - 1;
      strncat (dst, rptr, rlen);
      dst[slen + rlen] = '\0';
      strcat (dst, ".DIR.1");
      return 1;
    }
#endif /* VMS */
  /* Process as Unix format: just remove any final slash.
     But leave "/" unchanged; do not change it to "".  */
  strcpy (dst, src);
Jim Blandy's avatar
Jim Blandy committed
466
  if (slen > 1 && dst[slen - 1] == '/')
Jim Blandy's avatar
Jim Blandy committed
467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486
    dst[slen - 1] = 0;
  return 1;
}

DEFUN ("directory-file-name", Fdirectory_file_name, Sdirectory_file_name,
  1, 1, 0,
  "Returns the file name of the directory named DIR.\n\
This is the name of the file that holds the data for the directory DIR.\n\
This operation exists because a directory is also a file, but its name as\n\
a directory is different from its name as a file.\n\
In Unix-syntax, this function just removes the final slash.\n\
On VMS, given a VMS-syntax directory name such as \"[X.Y]\",\n\
it returns a file name such as \"[X]Y.DIR.1\".")
  (directory)
     Lisp_Object directory;
{
  char *buf;

  CHECK_STRING (directory, 0);

Jim Blandy's avatar
Jim Blandy committed
487
  if (NILP (directory))
Jim Blandy's avatar
Jim Blandy committed
488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518
    return Qnil;
#ifdef VMS
  /* 20 extra chars is insufficient for VMS, since we might perform a
     logical name translation. an equivalence string can be up to 255
     chars long, so grab that much extra space...  - sss */
  buf = (char *) alloca (XSTRING (directory)->size + 20 + 255);
#else
  buf = (char *) alloca (XSTRING (directory)->size + 20);
#endif
  directory_file_name (XSTRING (directory)->data, buf);
  return build_string (buf);
}

DEFUN ("make-temp-name", Fmake_temp_name, Smake_temp_name, 1, 1, 0,
  "Generate temporary file name (string) starting with PREFIX (a string).\n\
The Emacs process number forms part of the result,\n\
so there is no danger of generating a name being used by another process.")
  (prefix)
     Lisp_Object prefix;
{
  Lisp_Object val;
  val = concat2 (prefix, build_string ("XXXXXX"));
  mktemp (XSTRING (val)->data);
  return val;
}

DEFUN ("expand-file-name", Fexpand_file_name, Sexpand_file_name, 1, 2, 0,
  "Convert FILENAME to absolute, and canonicalize it.\n\
Second arg DEFAULT is directory to start with if FILENAME is relative\n\
 (does not start with slash); if DEFAULT is nil or missing,\n\
the current buffer's value of default-directory is used.\n\
Jim Blandy's avatar
Jim Blandy committed
519 520 521 522 523 524
Path components that are `.' are removed, and \n\
path components followed by `..' are removed, along with the `..' itself;\n\
note that these simplifications are done without checking the resulting\n\
paths in the file system.\n\
An initial `~/' expands to your home directory.\n\
An initial `~USER/' expands to USER's home directory.\n\
Jim Blandy's avatar
Jim Blandy committed
525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675
See also the function `substitute-in-file-name'.")
     (name, defalt)
     Lisp_Object name, defalt;
{
  unsigned char *nm;
  
  register unsigned char *newdir, *p, *o;
  int tlen;
  unsigned char *target;
  struct passwd *pw;
  int lose;
#ifdef VMS
  unsigned char * colon = 0;
  unsigned char * close = 0;
  unsigned char * slash = 0;
  unsigned char * brack = 0;
  int lbrack = 0, rbrack = 0;
  int dots = 0;
#endif /* VMS */
  
  CHECK_STRING (name, 0);

#ifdef VMS
  /* Filenames on VMS are always upper case.  */
  name = Fupcase (name);
#endif

  nm = XSTRING (name)->data;
  
  /* If nm is absolute, flush ...// and detect /./ and /../.
     If no /./ or /../ we can return right away. */
  if (
      nm[0] == '/'
#ifdef VMS
      || index (nm, ':')
#endif /* VMS */
      )
    {
      p = nm;
      lose = 0;
      while (*p)
	{
	  if (p[0] == '/' && p[1] == '/'
#ifdef APOLLO
	      /* // at start of filename is meaningful on Apollo system */
	      && nm != p
#endif /* APOLLO */
	      )
	    nm = p + 1;
	  if (p[0] == '/' && p[1] == '~')
	    nm = p + 1, lose = 1;
	  if (p[0] == '/' && p[1] == '.'
	      && (p[2] == '/' || p[2] == 0
		  || (p[2] == '.' && (p[3] == '/' || p[3] == 0))))
	    lose = 1;
#ifdef VMS
	  if (p[0] == '\\')
	    lose = 1;
	  if (p[0] == '/') {
	    /* if dev:[dir]/, move nm to / */
	    if (!slash && p > nm && (brack || colon)) {
	      nm = (brack ? brack + 1 : colon + 1);
	      lbrack = rbrack = 0;
	      brack = 0;
	      colon = 0;
	    }
	    slash = p;
	  }
	  if (p[0] == '-')
#ifndef VMS4_4
	    /* VMS pre V4.4,convert '-'s in filenames. */
	    if (lbrack == rbrack)
	      {
		if (dots < 2)	/* this is to allow negative version numbers */
		  p[0] = '_';
	      }
	    else
#endif /* VMS4_4 */
	      if (lbrack > rbrack &&
		  ((p[-1] == '.' || p[-1] == '[' || p[-1] == '<') &&
		   (p[1] == '.' || p[1] == ']' || p[1] == '>')))
		lose = 1;
#ifndef VMS4_4
	      else
		p[0] = '_';
#endif /* VMS4_4 */
	  /* count open brackets, reset close bracket pointer */
	  if (p[0] == '[' || p[0] == '<')
	    lbrack++, brack = 0;
	  /* count close brackets, set close bracket pointer */
	  if (p[0] == ']' || p[0] == '>')
	    rbrack++, brack = p;
	  /* detect ][ or >< */
	  if ((p[0] == ']' || p[0] == '>') && (p[1] == '[' || p[1] == '<'))
	    lose = 1;
	  if ((p[0] == ':' || p[0] == ']' || p[0] == '>') && p[1] == '~')
	    nm = p + 1, lose = 1;
	  if (p[0] == ':' && (colon || slash))
	    /* if dev1:[dir]dev2:, move nm to dev2: */
	    if (brack)
	      {
		nm = brack + 1;
		brack = 0;
	      }
	    /* if /pathname/dev:, move nm to dev: */
	    else if (slash)
	      nm = slash + 1;
	    /* if node::dev:, move colon following dev */
	    else if (colon && colon[-1] == ':')
	      colon = p;
	    /* if dev1:dev2:, move nm to dev2: */
	    else if (colon && colon[-1] != ':')
	      {
		nm = colon + 1;
		colon = 0;
	      }
	  if (p[0] == ':' && !colon)
	    {
	      if (p[1] == ':')
		p++;
	      colon = p;
	    }
	  if (lbrack == rbrack)
	    if (p[0] == ';')
	      dots = 2;
	    else if (p[0] == '.')
	      dots++;
#endif /* VMS */
	  p++;
	}
      if (!lose)
	{
#ifdef VMS
	  if (index (nm, '/'))
	    return build_string (sys_translate_unix (nm));
#endif /* VMS */
	  if (nm == XSTRING (name)->data)
	    return name;
	  return build_string (nm);
	}
    }

  /* Now determine directory to start with and put it in newdir */

  newdir = 0;

  if (nm[0] == '~')		/* prefix ~ */
    if (nm[1] == '/'
#ifdef VMS
	|| nm[1] == ':'
#endif /* VMS */
Jim Blandy's avatar
Jim Blandy committed
676
	|| nm[1] == 0)/* ~ by itself */
Jim Blandy's avatar
Jim Blandy committed
677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696
      {
	if (!(newdir = (unsigned char *) egetenv ("HOME")))
	  newdir = (unsigned char *) "";
	nm++;
#ifdef VMS
	nm++;			/* Don't leave the slash in nm.  */
#endif /* VMS */
      }
    else			/* ~user/filename */
      {
	for (p = nm; *p && (*p != '/'
#ifdef VMS
			    && *p != ':'
#endif /* VMS */
			    ); p++);
	o = (unsigned char *) alloca (p - nm + 1);
	bcopy ((char *) nm, o, p - nm);
	o [p - nm] = 0;

	pw = (struct passwd *) getpwnam (o + 1);
Jim Blandy's avatar
Jim Blandy committed
697 698 699
	if (pw)
	  {
	    newdir = (unsigned char *) pw -> pw_dir;
Jim Blandy's avatar
Jim Blandy committed
700
#ifdef VMS
Jim Blandy's avatar
Jim Blandy committed
701
	    nm = p + 1;		/* skip the terminator */
Jim Blandy's avatar
Jim Blandy committed
702
#else
Jim Blandy's avatar
Jim Blandy committed
703
	    nm = p;
Jim Blandy's avatar
Jim Blandy committed
704
#endif /* VMS */
Jim Blandy's avatar
Jim Blandy committed
705 706 707 708
	  }

	/* If we don't find a user of that name, leave the name
	   unchanged; don't move nm forward to p.  */
Jim Blandy's avatar
Jim Blandy committed
709 710 711 712 713 714 715 716
      }

  if (nm[0] != '/'
#ifdef VMS
      && !index (nm, ':')
#endif /* not VMS */
      && !newdir)
    {
Jim Blandy's avatar
Jim Blandy committed
717
      if (NILP (defalt))
Jim Blandy's avatar
Jim Blandy committed
718 719 720 721 722
	defalt = current_buffer->directory;
      CHECK_STRING (defalt, 1);
      newdir = XSTRING (defalt)->data;
    }

Jim Blandy's avatar
Jim Blandy committed
723 724 725 726 727 728 729 730 731 732 733 734 735 736 737
  if (newdir != 0)
    {
      /* Get rid of any slash at the end of newdir.  */
      int length = strlen (newdir);
      if (newdir[length - 1] == '/')
	{
	  unsigned char *temp = (unsigned char *) alloca (length);
	  bcopy (newdir, temp, length - 1);
	  temp[length - 1] = 0;
	  newdir = temp;
	}
      tlen = length + 1;
    }
  else
    tlen = 0;
Jim Blandy's avatar
Jim Blandy committed
738

Jim Blandy's avatar
Jim Blandy committed
739 740
  /* Now concatenate the directory and name to new space in the stack frame */
  tlen += strlen (nm) + 1;
Jim Blandy's avatar
Jim Blandy committed
741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851
  target = (unsigned char *) alloca (tlen);
  *target = 0;

  if (newdir)
    {
#ifndef VMS
      if (nm[0] == 0 || nm[0] == '/')
	strcpy (target, newdir);
      else
#endif
      file_name_as_directory (target, newdir);
    }

  strcat (target, nm);
#ifdef VMS
  if (index (target, '/'))
    strcpy (target, sys_translate_unix (target));
#endif /* VMS */

  /* Now canonicalize by removing /. and /foo/.. if they appear */

  p = target;
  o = target;

  while (*p)
    {
#ifdef VMS
      if (*p != ']' && *p != '>' && *p != '-')
	{
	  if (*p == '\\')
	    p++;
	  *o++ = *p++;
	}
      else if ((p[0] == ']' || p[0] == '>') && p[0] == p[1] + 2)
	/* brackets are offset from each other by 2 */
	{
	  p += 2;
	  if (*p != '.' && *p != '-' && o[-1] != '.')
	    /* convert [foo][bar] to [bar] */
	    while (o[-1] != '[' && o[-1] != '<')
	      o--;
	  else if (*p == '-' && *o != '.')
	    *--p = '.';
	}
      else if (p[0] == '-' && o[-1] == '.' &&
	       (p[1] == '.' || p[1] == ']' || p[1] == '>'))
	/* flush .foo.- ; leave - if stopped by '[' or '<' */
	{
	  do
	    o--;
	  while (o[-1] != '.' && o[-1] != '[' && o[-1] != '<');
	  if (p[1] == '.')	/* foo.-.bar ==> bar*/
	    p += 2;
	  else if (o[-1] == '.') /* '.foo.-]' ==> ']' */
	    p++, o--;
	  /* else [foo.-] ==> [-] */
	}
      else
	{
#ifndef VMS4_4
	  if (*p == '-' &&
	      o[-1] != '[' && o[-1] != '<' && o[-1] != '.' &&
	      p[1] != ']' && p[1] != '>' && p[1] != '.')
	    *p = '_';
#endif /* VMS4_4 */
	  *o++ = *p++;
	}
#else /* not VMS */
      if (*p != '/')
 	{
	  *o++ = *p++;
	}
      else if (!strncmp (p, "//", 2)
#ifdef APOLLO
	       /* // at start of filename is meaningful in Apollo system */
	       && o != target
#endif /* APOLLO */
	       )
	{
	  o = target;
	  p++;
	}
      else if (p[0] == '/' && p[1] == '.' &&
	       (p[2] == '/' || p[2] == 0))
	p += 2;
      else if (!strncmp (p, "/..", 3)
	       /* `/../' is the "superroot" on certain file systems.  */
	       && o != target
	       && (p[3] == '/' || p[3] == 0))
	{
	  while (o != target && *--o != '/')
	    ;
#ifdef APOLLO
	  if (o == target + 1 && o[-1] == '/' && o[0] == '/')
	    ++o;
	  else
#endif /* APOLLO */
	  if (o == target && *o == '/')
	    ++o;
	  p += 3;
	}
      else
 	{
	  *o++ = *p++;
	}
#endif /* not VMS */
    }

  return make_string (target, o - target);
}
#if 0
Jim Blandy's avatar
Jim Blandy committed
852 853
/* Changed this DEFUN to a DEAFUN, so as not to confuse `make-docfile'.
DEAFUN ("expand-file-name", Fexpand_file_name, Sexpand_file_name, 1, 2, 0,
Jim Blandy's avatar
Jim Blandy committed
854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053
  "Convert FILENAME to absolute, and canonicalize it.\n\
Second arg DEFAULT is directory to start with if FILENAME is relative\n\
 (does not start with slash); if DEFAULT is nil or missing,\n\
the current buffer's value of default-directory is used.\n\
Filenames containing `.' or `..' as components are simplified;\n\
initial `~/' expands to your home directory.\n\
See also the function `substitute-in-file-name'.")
     (name, defalt)
     Lisp_Object name, defalt;
{
  unsigned char *nm;
  
  register unsigned char *newdir, *p, *o;
  int tlen;
  unsigned char *target;
  struct passwd *pw;
  int lose;
#ifdef VMS
  unsigned char * colon = 0;
  unsigned char * close = 0;
  unsigned char * slash = 0;
  unsigned char * brack = 0;
  int lbrack = 0, rbrack = 0;
  int dots = 0;
#endif /* VMS */
  
  CHECK_STRING (name, 0);

#ifdef VMS
  /* Filenames on VMS are always upper case.  */
  name = Fupcase (name);
#endif

  nm = XSTRING (name)->data;
  
  /* If nm is absolute, flush ...// and detect /./ and /../.
     If no /./ or /../ we can return right away. */
  if (
      nm[0] == '/'
#ifdef VMS
      || index (nm, ':')
#endif /* VMS */
      )
    {
      p = nm;
      lose = 0;
      while (*p)
	{
	  if (p[0] == '/' && p[1] == '/'
#ifdef APOLLO
	      /* // at start of filename is meaningful on Apollo system */
	      && nm != p
#endif /* APOLLO */
	      )
	    nm = p + 1;
	  if (p[0] == '/' && p[1] == '~')
	    nm = p + 1, lose = 1;
	  if (p[0] == '/' && p[1] == '.'
	      && (p[2] == '/' || p[2] == 0
		  || (p[2] == '.' && (p[3] == '/' || p[3] == 0))))
	    lose = 1;
#ifdef VMS
	  if (p[0] == '\\')
	    lose = 1;
	  if (p[0] == '/') {
	    /* if dev:[dir]/, move nm to / */
	    if (!slash && p > nm && (brack || colon)) {
	      nm = (brack ? brack + 1 : colon + 1);
	      lbrack = rbrack = 0;
	      brack = 0;
	      colon = 0;
	    }
	    slash = p;
	  }
	  if (p[0] == '-')
#ifndef VMS4_4
	    /* VMS pre V4.4,convert '-'s in filenames. */
	    if (lbrack == rbrack)
	      {
		if (dots < 2)	/* this is to allow negative version numbers */
		  p[0] = '_';
	      }
	    else
#endif /* VMS4_4 */
	      if (lbrack > rbrack &&
		  ((p[-1] == '.' || p[-1] == '[' || p[-1] == '<') &&
		   (p[1] == '.' || p[1] == ']' || p[1] == '>')))
		lose = 1;
#ifndef VMS4_4
	      else
		p[0] = '_';
#endif /* VMS4_4 */
	  /* count open brackets, reset close bracket pointer */
	  if (p[0] == '[' || p[0] == '<')
	    lbrack++, brack = 0;
	  /* count close brackets, set close bracket pointer */
	  if (p[0] == ']' || p[0] == '>')
	    rbrack++, brack = p;
	  /* detect ][ or >< */
	  if ((p[0] == ']' || p[0] == '>') && (p[1] == '[' || p[1] == '<'))
	    lose = 1;
	  if ((p[0] == ':' || p[0] == ']' || p[0] == '>') && p[1] == '~')
	    nm = p + 1, lose = 1;
	  if (p[0] == ':' && (colon || slash))
	    /* if dev1:[dir]dev2:, move nm to dev2: */
	    if (brack)
	      {
		nm = brack + 1;
		brack = 0;
	      }
	    /* if /pathname/dev:, move nm to dev: */
	    else if (slash)
	      nm = slash + 1;
	    /* if node::dev:, move colon following dev */
	    else if (colon && colon[-1] == ':')
	      colon = p;
	    /* if dev1:dev2:, move nm to dev2: */
	    else if (colon && colon[-1] != ':')
	      {
		nm = colon + 1;
		colon = 0;
	      }
	  if (p[0] == ':' && !colon)
	    {
	      if (p[1] == ':')
		p++;
	      colon = p;
	    }
	  if (lbrack == rbrack)
	    if (p[0] == ';')
	      dots = 2;
	    else if (p[0] == '.')
	      dots++;
#endif /* VMS */
	  p++;
	}
      if (!lose)
	{
#ifdef VMS
	  if (index (nm, '/'))
	    return build_string (sys_translate_unix (nm));
#endif /* VMS */
	  if (nm == XSTRING (name)->data)
	    return name;
	  return build_string (nm);
	}
    }

  /* Now determine directory to start with and put it in NEWDIR */

  newdir = 0;

  if (nm[0] == '~')		/* prefix ~ */
    if (nm[1] == '/'
#ifdef VMS
	|| nm[1] == ':'
#endif /* VMS */
	|| nm[1] == 0)/* ~/filename */
      {
	if (!(newdir = (unsigned char *) egetenv ("HOME")))
	  newdir = (unsigned char *) "";
	nm++;
#ifdef VMS
	nm++;			/* Don't leave the slash in nm.  */
#endif /* VMS */
      }
    else  /* ~user/filename */
      {
	/* Get past ~ to user */
	unsigned char *user = nm + 1;
	/* Find end of name. */
	unsigned char *ptr = (unsigned char *) index (user, '/');
	int len = ptr ? ptr - user : strlen (user);
#ifdef VMS
	unsigned char *ptr1 = index (user, ':');
	if (ptr1 != 0 && ptr1 - user < len)
	  len = ptr1 - user;
#endif				/* VMS */
	/* Copy the user name into temp storage. */
	o = (unsigned char *) alloca (len + 1);
	bcopy ((char *) user, o, len);
	o[len] = 0;

	/* Look up the user name. */
	pw = (struct passwd *) getpwnam (o + 1);
	if (!pw)
	  error ("\"%s\" isn't a registered user", o + 1);

	newdir = (unsigned char *) pw->pw_dir;

	/* Discard the user name from NM.  */
	nm += len;
      }

  if (nm[0] != '/'
#ifdef VMS
      && !index (nm, ':')
#endif /* not VMS */
      && !newdir)
    {
Jim Blandy's avatar
Jim Blandy committed
1054
      if (NILP (defalt))
Jim Blandy's avatar
Jim Blandy committed
1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368
	defalt = current_buffer->directory;
      CHECK_STRING (defalt, 1);
      newdir = XSTRING (defalt)->data;
    }

  /* Now concatenate the directory and name to new space in the stack frame */

  tlen = (newdir ? strlen (newdir) + 1 : 0) + strlen (nm) + 1;
  target = (unsigned char *) alloca (tlen);
  *target = 0;

  if (newdir)
    {
#ifndef VMS
      if (nm[0] == 0 || nm[0] == '/')
	strcpy (target, newdir);
      else
#endif
      file_name_as_directory (target, newdir);
    }

  strcat (target, nm);
#ifdef VMS
  if (index (target, '/'))
    strcpy (target, sys_translate_unix (target));
#endif /* VMS */

  /* Now canonicalize by removing /. and /foo/.. if they appear */

  p = target;
  o = target;

  while (*p)
    {
#ifdef VMS
      if (*p != ']' && *p != '>' && *p != '-')
	{
	  if (*p == '\\')
	    p++;
	  *o++ = *p++;
	}
      else if ((p[0] == ']' || p[0] == '>') && p[0] == p[1] + 2)
	/* brackets are offset from each other by 2 */
	{
	  p += 2;
	  if (*p != '.' && *p != '-' && o[-1] != '.')
	    /* convert [foo][bar] to [bar] */
	    while (o[-1] != '[' && o[-1] != '<')
	      o--;
	  else if (*p == '-' && *o != '.')
	    *--p = '.';
	}
      else if (p[0] == '-' && o[-1] == '.' &&
	       (p[1] == '.' || p[1] == ']' || p[1] == '>'))
	/* flush .foo.- ; leave - if stopped by '[' or '<' */
	{
	  do
	    o--;
	  while (o[-1] != '.' && o[-1] != '[' && o[-1] != '<');
	  if (p[1] == '.')	/* foo.-.bar ==> bar*/
	    p += 2;
	  else if (o[-1] == '.') /* '.foo.-]' ==> ']' */
	    p++, o--;
	  /* else [foo.-] ==> [-] */
	}
      else
	{
#ifndef VMS4_4
	  if (*p == '-' &&
	      o[-1] != '[' && o[-1] != '<' && o[-1] != '.' &&
	      p[1] != ']' && p[1] != '>' && p[1] != '.')
	    *p = '_';
#endif /* VMS4_4 */
	  *o++ = *p++;
	}
#else /* not VMS */
      if (*p != '/')
 	{
	  *o++ = *p++;
	}
      else if (!strncmp (p, "//", 2)
#ifdef APOLLO
	       /* // at start of filename is meaningful in Apollo system */
	       && o != target
#endif /* APOLLO */
	       )
	{
	  o = target;
	  p++;
	}
      else if (p[0] == '/' && p[1] == '.' &&
	       (p[2] == '/' || p[2] == 0))
	p += 2;
      else if (!strncmp (p, "/..", 3)
	       /* `/../' is the "superroot" on certain file systems.  */
	       && o != target
	       && (p[3] == '/' || p[3] == 0))
	{
	  while (o != target && *--o != '/')
	    ;
#ifdef APOLLO
	  if (o == target + 1 && o[-1] == '/' && o[0] == '/')
	    ++o;
	  else
#endif /* APOLLO */
	  if (o == target && *o == '/')
	    ++o;
	  p += 3;
	}
      else
 	{
	  *o++ = *p++;
	}
#endif /* not VMS */
    }

  return make_string (target, o - target);
}
#endif

DEFUN ("substitute-in-file-name", Fsubstitute_in_file_name,
  Ssubstitute_in_file_name, 1, 1, 0,
  "Substitute environment variables referred to in FILENAME.\n\
`$FOO' where FOO is an environment variable name means to substitute\n\
the value of that variable.  The variable name should be terminated\n\
with a character not a letter, digit or underscore; otherwise, enclose\n\
the entire variable name in braces.\n\
If `/~' appears, all of FILENAME through that `/' is discarded.\n\n\
On VMS, `$' substitution is not done; this function does little and only\n\
duplicates what `expand-file-name' does.")
  (string)
     Lisp_Object string;
{
  unsigned char *nm;

  register unsigned char *s, *p, *o, *x, *endp;
  unsigned char *target;
  int total = 0;
  int substituted = 0;
  unsigned char *xnm;

  CHECK_STRING (string, 0);

  nm = XSTRING (string)->data;
  endp = nm + XSTRING (string)->size;

  /* If /~ or // appears, discard everything through first slash. */

  for (p = nm; p != endp; p++)
    {
      if ((p[0] == '~' ||
#ifdef APOLLO
	   /* // at start of file name is meaningful in Apollo system */
	   (p[0] == '/' && p - 1 != nm)
#else /* not APOLLO */
	   p[0] == '/'
#endif /* not APOLLO */
	   )
	  && p != nm &&
#ifdef VMS
	  (p[-1] == ':' || p[-1] == ']' || p[-1] == '>' ||
#endif /* VMS */
	  p[-1] == '/')
#ifdef VMS
	  )
#endif /* VMS */
	{
	  nm = p;
	  substituted = 1;
	}
    }

#ifdef VMS
  return build_string (nm);
#else

  /* See if any variables are substituted into the string
     and find the total length of their values in `total' */

  for (p = nm; p != endp;)
    if (*p != '$')
      p++;
    else
      {
	p++;
	if (p == endp)
	  goto badsubst;
	else if (*p == '$')
	  {
	    /* "$$" means a single "$" */
	    p++;
	    total -= 1;
	    substituted = 1;
	    continue;
	  }
	else if (*p == '{')
	  {
	    o = ++p;
	    while (p != endp && *p != '}') p++;
	    if (*p != '}') goto missingclose;
	    s = p;
	  }
	else
	  {
	    o = p;
	    while (p != endp && (isalnum (*p) || *p == '_')) p++;
	    s = p;
	  }

	/* Copy out the variable name */
	target = (unsigned char *) alloca (s - o + 1);
	strncpy (target, o, s - o);
	target[s - o] = 0;

	/* Get variable value */
	o = (unsigned char *) egetenv (target);
/* The presence of this code makes vax 5.0 crash, for reasons yet unknown */
#if 0
#ifdef USG
	if (!o && !strcmp (target, "USER"))
	  o = egetenv ("LOGNAME");
#endif /* USG */
#endif /* 0 */
	if (!o) goto badvar;
	total += strlen (o);
	substituted = 1;
      }

  if (!substituted)
    return string;

  /* If substitution required, recopy the string and do it */
  /* Make space in stack frame for the new copy */
  xnm = (unsigned char *) alloca (XSTRING (string)->size + total + 1);
  x = xnm;

  /* Copy the rest of the name through, replacing $ constructs with values */
  for (p = nm; *p;)
    if (*p != '$')
      *x++ = *p++;
    else
      {
	p++;
	if (p == endp)
	  goto badsubst;
	else if (*p == '$')
	  {
	    *x++ = *p++;
	    continue;
	  }
	else if (*p == '{')
	  {
	    o = ++p;
	    while (p != endp && *p != '}') p++;
	    if (*p != '}') goto missingclose;
	    s = p++;
	  }
	else
	  {
	    o = p;
	    while (p != endp && (isalnum (*p) || *p == '_')) p++;
	    s = p;
	  }

	/* Copy out the variable name */
	target = (unsigned char *) alloca (s - o + 1);
	strncpy (target, o, s - o);
	target[s - o] = 0;

	/* Get variable value */
	o = (unsigned char *) egetenv (target);
/* The presence of this code makes vax 5.0 crash, for reasons yet unknown */
#if 0
#ifdef USG
	if (!o && !strcmp (target, "USER"))
	  o = egetenv ("LOGNAME");
#endif /* USG */
#endif /* 0 */
	if (!o)
	  goto badvar;

	strcpy (x, o);
	x += strlen (o);
      }

  *x = 0;

  /* If /~ or // appears, discard everything through first slash. */

  for (p = xnm; p != x; p++)
    if ((p[0] == '~' ||
#ifdef APOLLO
	 /* // at start of file name is meaningful in Apollo system */
	 (p[0] == '/' && p - 1 != xnm)
#else /* not APOLLO */
	 p[0] == '/'
#endif /* not APOLLO */
	 )
	&& p != nm && p[-1] == '/')
      xnm = p;

  return make_string (xnm, x - xnm);

 badsubst:
  error ("Bad format environment-variable substitution");
 missingclose:
  error ("Missing \"}\" in environment-variable substitution");
 badvar:
  error ("Substituting nonexistent environment variable \"%s\"", target);

  /* NOTREACHED */
#endif /* not VMS */
}

Jim Blandy's avatar
Jim Blandy committed
1369 1370 1371 1372 1373 1374 1375
/* A slightly faster and more convenient way to get
   (directory-file-name (expand-file-name FOO)).  The return value may
   have had its last character zapped with a '\0' character, meaning
   that it is acceptable to system calls, but not to other lisp
   functions.  Callers should make sure that the return value doesn't
   escape.  */

Jim Blandy's avatar
Jim Blandy committed
1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420
Lisp_Object
expand_and_dir_to_file (filename, defdir)
     Lisp_Object filename, defdir;
{
  register Lisp_Object abspath;

  abspath = Fexpand_file_name (filename, defdir);
#ifdef VMS
  {
    register int c = XSTRING (abspath)->data[XSTRING (abspath)->size - 1];
    if (c == ':' || c == ']' || c == '>')
      abspath = Fdirectory_file_name (abspath);
  }
#else
  /* Remove final slash, if any (unless path is root).
     stat behaves differently depending!  */
  if (XSTRING (abspath)->size > 1
      && XSTRING (abspath)->data[XSTRING (abspath)->size - 1] == '/')
    {
      if (EQ (abspath, filename))
	abspath = Fcopy_sequence (abspath);
      XSTRING (abspath)->data[XSTRING (abspath)->size - 1] = 0;
    }
#endif
  return abspath;
}

barf_or_query_if_file_exists (absname, querystring, interactive)
     Lisp_Object absname;
     unsigned char *querystring;
     int interactive;
{
  register Lisp_Object tem;
  struct gcpro gcpro1;

  if (access (XSTRING (absname)->data, 4) >= 0)
    {
      if (! interactive)
	Fsignal (Qfile_already_exists,
		 Fcons (build_string ("File already exists"),
			Fcons (absname, Qnil)));
      GCPRO1 (absname);
      tem = do_yes_or_no_p (format1 ("File %s already exists; %s anyway? ",
				     XSTRING (absname)->data, querystring));
      UNGCPRO;
Jim Blandy's avatar
Jim Blandy committed
1421
      if (NILP (tem))
Jim Blandy's avatar
Jim Blandy committed
1422 1423 1424 1425 1426 1427 1428 1429
	Fsignal (Qfile_already_exists,
		 Fcons (build_string ("File already exists"),
			Fcons (absname, Qnil)));
    }
  return;
}

DEFUN ("copy-file", Fcopy_file, Scopy_file, 2, 4,
Jim Blandy's avatar
Jim Blandy committed
1430
  "fCopy file: \nFCopy %s to file: \np\nP",
Jim Blandy's avatar
Jim Blandy committed
1431 1432 1433 1434 1435
  "Copy FILE to NEWNAME.  Both args must be strings.\n\
Signals a `file-already-exists' error if file NEWNAME already exists,\n\
unless a third argument OK-IF-ALREADY-EXISTS is supplied and non-nil.\n\
A number as third arg means request confirmation if NEWNAME already exists.\n\
This is what happens in interactive use with M-x.\n\
Jim Blandy's avatar
Jim Blandy committed
1436 1437 1438
Fourth arg KEEP-TIME non-nil means give the new file the same\n\
last-modified time as the old one.  (This works on only some systems.)\n\
A prefix arg makes KEEP-TIME non-nil.")
Jim Blandy's avatar
Jim Blandy committed
1439 1440 1441 1442 1443 1444
  (filename, newname, ok_if_already_exists, keep_date)
     Lisp_Object filename, newname, ok_if_already_exists, keep_date;
{
  int ifd, ofd, n;
  char buf[16 * 1024];
  struct stat st;
1445
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1446
  struct gcpro gcpro1, gcpro2;
1447
  int count = specpdl_ptr - specpdl;
Jim Blandy's avatar
Jim Blandy committed
1448 1449 1450 1451 1452 1453

  GCPRO2 (filename, newname);
  CHECK_STRING (filename, 0);
  CHECK_STRING (newname, 1);
  filename = Fexpand_file_name (filename, Qnil);
  newname = Fexpand_file_name (newname, Qnil);
1454 1455 1456 1457 1458 1459 1460

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call3 (handler, Qcopy_file, filename, newname);

Jim Blandy's avatar
Jim Blandy committed
1461
  if (NILP (ok_if_already_exists)
Jim Blandy's avatar
Jim Blandy committed
1462 1463 1464 1465 1466 1467 1468 1469
      || XTYPE (ok_if_already_exists) == Lisp_Int)
    barf_or_query_if_file_exists (newname, "copy to it",
				  XTYPE (ok_if_already_exists) == Lisp_Int);

  ifd = open (XSTRING (filename)->data, 0);
  if (ifd < 0)
    report_file_error ("Opening input file", Fcons (filename, Qnil));

1470 1471
  record_unwind_protect (close_file_unwind, make_number (ifd));

Jim Blandy's avatar
Jim Blandy committed
1472 1473 1474 1475 1476 1477 1478
#ifdef VMS
  /* Create the copy file with the same record format as the input file */
  ofd = sys_creat (XSTRING (newname)->data, 0666, ifd);
#else
  ofd = creat (XSTRING (newname)->data, 0666);
#endif /* VMS */
  if (ofd < 0)
Jim Blandy's avatar
Jim Blandy committed
1479
      report_file_error ("Opening output file", Fcons (newname, Qnil));
1480 1481

  record_unwind_protect (close_file_unwind, make_number (ofd));
Jim Blandy's avatar
Jim Blandy committed
1482

1483 1484
  immediate_quit = 1;
  QUIT;
Jim Blandy's avatar
Jim Blandy committed
1485 1486
  while ((n = read (ifd, buf, sizeof buf)) > 0)
    if (write (ofd, buf, n) != n)
Jim Blandy's avatar
Jim Blandy committed
1487
	report_file_error ("I/O error", Fcons (newname, Qnil));
1488
  immediate_quit = 0;
Jim Blandy's avatar
Jim Blandy committed
1489 1490 1491

  if (fstat (ifd, &st) >= 0)
    {
Jim Blandy's avatar
Jim Blandy committed
1492
      if (!NILP (keep_date))
Jim Blandy's avatar
Jim Blandy committed
1493
	{
Jim Blandy's avatar
Jim Blandy committed
1494 1495 1496 1497
	  EMACS_TIME atime, mtime;
	  EMACS_SET_SECS_USECS (atime, st.st_atime, 0);
	  EMACS_SET_SECS_USECS (mtime, st.st_mtime, 0);
	  EMACS_SET_UTIMES (XSTRING (newname)->data, atime, mtime);
Jim Blandy's avatar
Jim Blandy committed
1498 1499 1500 1501
	}
#ifdef APOLLO
      if (!egetenv ("USE_DOMAIN_ACLS"))
#endif
Jim Blandy's avatar
Jim Blandy committed
1502
	chmod (XSTRING (newname)->data, st.st_mode & 07777);
Jim Blandy's avatar
Jim Blandy committed
1503 1504
    }

1505 1506 1507
  /* Discard the unwind protects.  */
  specpdl_ptr = specpdl + count;

Jim Blandy's avatar
Jim Blandy committed
1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521
  close (ifd);
  if (close (ofd) < 0)
    report_file_error ("I/O error", Fcons (newname, Qnil));

  UNGCPRO;
  return Qnil;
}

DEFUN ("make-directory", Fmake_directory, Smake_directory, 1, 1, "FMake directory: ",
  "Create a directory.  One argument, a file name string.")
  (dirname)
     Lisp_Object dirname;
{
  unsigned char *dir;
1522
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1523 1524 1525

  CHECK_STRING (dirname, 0);
  dirname = Fexpand_file_name (dirname, Qnil);
1526 1527 1528 1529 1530

  handler = find_file_handler (dirname);
  if (!NILP (handler))
    return call2 (handler, Qmake_directory, dirname);
 
Jim Blandy's avatar
Jim Blandy committed
1531 1532 1533 1534 1535
  dir = XSTRING (dirname)->data;

  if (mkdir (dir, 0777) != 0)
    report_file_error ("Creating directory", Flist (1, &dirname));

1536
  return Qnil;
Jim Blandy's avatar
Jim Blandy committed
1537 1538
}

1539 1540
DEFUN ("delete-directory", Fdelete_directory, Sdelete_directory, 1, 1, "FDelete directory: ",
  "Delete a directory.  One argument, a file name string.")
Jim Blandy's avatar
Jim Blandy committed
1541 1542 1543 1544
  (dirname)
     Lisp_Object dirname;
{
  unsigned char *dir;
1545
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1546 1547 1548 1549 1550

  CHECK_STRING (dirname, 0);
  dirname = Fexpand_file_name (dirname, Qnil);
  dir = XSTRING (dirname)->data;

1551 1552 1553 1554
  handler = find_file_handler (dirname);
  if (!NILP (handler))
    return call2 (handler, Qdelete_directory, dirname);

Jim Blandy's avatar
Jim Blandy committed
1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566
  if (rmdir (dir) != 0)
    report_file_error ("Removing directory", Flist (1, &dirname));

  return Qnil;
}

DEFUN ("delete-file", Fdelete_file, Sdelete_file, 1, 1, "fDelete file: ",
  "Delete specified file.  One argument, a file name string.\n\
If file has multiple names, it continues to exist with the other names.")
  (filename)
     Lisp_Object filename;
{
1567
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1568 1569
  CHECK_STRING (filename, 0);
  filename = Fexpand_file_name (filename, Qnil);
1570 1571 1572 1573 1574

  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call2 (handler, Qdelete_file, filename);

Jim Blandy's avatar
Jim Blandy committed
1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593
  if (0 > unlink (XSTRING (filename)->data))
    report_file_error ("Removing old name", Flist (1, &filename));
  return Qnil;
}

DEFUN ("rename-file", Frename_file, Srename_file, 2, 3,
  "fRename file: \nFRename %s to file: \np",
  "Rename FILE as NEWNAME.  Both args strings.\n\
If file has names other than FILE, it continues to have those names.\n\
Signals a `file-already-exists' error if a file NEWNAME already exists\n\
unless optional third argument OK-IF-ALREADY-EXISTS is non-nil.\n\
A number as third arg means request confirmation if NEWNAME already exists.\n\
This is what happens in interactive use with M-x.")
  (filename, newname, ok_if_already_exists)
     Lisp_Object filename, newname, ok_if_already_exists;
{
#ifdef NO_ARG_ARRAY
  Lisp_Object args[2];
#endif
1594
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1595 1596 1597 1598 1599 1600 1601
  struct gcpro gcpro1, gcpro2;

  GCPRO2 (filename, newname);
  CHECK_STRING (filename, 0);
  CHECK_STRING (newname, 1);
  filename = Fexpand_file_name (filename, Qnil);
  newname = Fexpand_file_name (newname, Qnil);
1602 1603 1604 1605 1606 1607 1608

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call3 (handler, Qrename_file, filename, newname);

Jim Blandy's avatar
Jim Blandy committed
1609
  if (NILP (ok_if_already_exists)
Jim Blandy's avatar
Jim Blandy committed
1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652
      || XTYPE (ok_if_already_exists) == Lisp_Int)
    barf_or_query_if_file_exists (newname, "rename to it",
				  XTYPE (ok_if_already_exists) == Lisp_Int);
#ifndef BSD4_1
  if (0 > rename (XSTRING (filename)->data, XSTRING (newname)->data))
#else
  if (0 > link (XSTRING (filename)->data, XSTRING (newname)->data)
      || 0 > unlink (XSTRING (filename)->data))
#endif
    {
      if (errno == EXDEV)
	{
	  Fcopy_file (filename, newname, ok_if_already_exists, Qt);
	  Fdelete_file (filename);
	}
      else
#ifdef NO_ARG_ARRAY
	{
	  args[0] = filename;
	  args[1] = newname;
	  report_file_error ("Renaming", Flist (2, args));
	}
#else
	report_file_error ("Renaming", Flist (2, &filename));
#endif
    }
  UNGCPRO;
  return Qnil;
}

DEFUN ("add-name-to-file", Fadd_name_to_file, Sadd_name_to_file, 2, 3,
  "fAdd name to file: \nFName to add to %s: \np",
  "Give FILE additional name NEWNAME.  Both args strings.\n\
Signals a `file-already-exists' error if a file NEWNAME already exists\n\
unless optional third argument OK-IF-ALREADY-EXISTS is non-nil.\n\
A number as third arg means request confirmation if NEWNAME already exists.\n\
This is what happens in interactive use with M-x.")
  (filename, newname, ok_if_already_exists)
     Lisp_Object filename, newname, ok_if_already_exists;
{
#ifdef NO_ARG_ARRAY
  Lisp_Object args[2];
#endif
1653
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1654 1655 1656 1657 1658 1659 1660
  struct gcpro gcpro1, gcpro2;

  GCPRO2 (filename, newname);
  CHECK_STRING (filename, 0);
  CHECK_STRING (newname, 1);
  filename = Fexpand_file_name (filename, Qnil);
  newname = Fexpand_file_name (newname, Qnil);
1661 1662 1663 1664 1665 1666 1667

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call3 (handler, Qadd_name_to_file, filename, newname);

Jim Blandy's avatar
Jim Blandy committed
1668
  if (NILP (ok_if_already_exists)
Jim Blandy's avatar
Jim Blandy committed
1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695
      || XTYPE (ok_if_already_exists) == Lisp_Int)
    barf_or_query_if_file_exists (newname, "make it a new name",
				  XTYPE (ok_if_already_exists) == Lisp_Int);
  unlink (XSTRING (newname)->data);
  if (0 > link (XSTRING (filename)->data, XSTRING (newname)->data))
    {
#ifdef NO_ARG_ARRAY
      args[0] = filename;
      args[1] = newname;
      report_file_error ("Adding new name", Flist (2, args));
#else
      report_file_error ("Adding new name", Flist (2, &filename));
#endif
    }

  UNGCPRO;
  return Qnil;
}

#ifdef S_IFLNK
DEFUN ("make-symbolic-link", Fmake_symbolic_link, Smake_symbolic_link, 2, 3,
  "FMake symbolic link to file: \nFMake symbolic link to file %s: \np",
  "Make a symbolic link to FILENAME, named LINKNAME.  Both args strings.\n\
Signals a `file-already-exists' error if a file NEWNAME already exists\n\
unless optional third argument OK-IF-ALREADY-EXISTS is non-nil.\n\
A number as third arg means request confirmation if NEWNAME already exists.\n\
This happens for interactive use with M-x.")
Jim Blandy's avatar
Jim Blandy committed
1696 1697
  (filename, linkname, ok_if_already_exists)
     Lisp_Object filename, linkname, ok_if_already_exists;
Jim Blandy's avatar
Jim Blandy committed
1698 1699 1700 1701
{
#ifdef NO_ARG_ARRAY
  Lisp_Object args[2];
#endif
1702
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1703 1704
  struct gcpro gcpro1, gcpro2;

Jim Blandy's avatar
Jim Blandy committed
1705
  GCPRO2 (filename, linkname);
Jim Blandy's avatar
Jim Blandy committed
1706
  CHECK_STRING (filename, 0);
Jim Blandy's avatar
Jim Blandy committed
1707
  CHECK_STRING (linkname, 1);
Jim Blandy's avatar
Jim Blandy committed
1708 1709 1710
#if 0 /* This made it impossible to make a link to a relative name.  */
  filename = Fexpand_file_name (filename, Qnil);
#endif
Jim Blandy's avatar
Jim Blandy committed
1711
  linkname = Fexpand_file_name (linkname, Qnil);
1712 1713 1714 1715 1716

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
Jim Blandy's avatar
Jim Blandy committed
1717
    return call3 (handler, Qmake_symbolic_link, filename, linkname);
1718

Jim Blandy's avatar
Jim Blandy committed
1719
  if (NILP (ok_if_already_exists)
Jim Blandy's avatar
Jim Blandy committed
1720
      || XTYPE (ok_if_already_exists) == Lisp_Int)
Jim Blandy's avatar
Jim Blandy committed
1721
    barf_or_query_if_file_exists (linkname, "make it a link",
Jim Blandy's avatar
Jim Blandy committed
1722
				  XTYPE (ok_if_already_exists) == Lisp_Int);
Jim Blandy's avatar
Jim Blandy committed
1723
  if (0 > symlink (XSTRING (filename)->data, XSTRING (linkname)->data))
Jim Blandy's avatar
Jim Blandy committed
1724 1725 1726 1727 1728
    {
      /* If we didn't complain already, silently delete existing file.  */
      if (errno == EEXIST)
	{
	  unlink (XSTRING (filename)->data);
Jim Blandy's avatar
Jim Blandy committed
1729
	  if (0 <= symlink (XSTRING (filename)->data, XSTRING (linkname)->data))
Jim Blandy's avatar
Jim Blandy committed
1730 1731 1732 1733 1734
	    return Qnil;
	}

#ifdef NO_ARG_ARRAY
      args[0] = filename;
Jim Blandy's avatar
Jim Blandy committed
1735
      args[1] = linkname;
Jim Blandy's avatar
Jim Blandy committed
1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756
      report_file_error ("Making symbolic link", Flist (2, args));
#else
      report_file_error ("Making symbolic link", Flist (2, &filename));
#endif
    }
  UNGCPRO;
  return Qnil;
}
#endif /* S_IFLNK */

#ifdef VMS

DEFUN ("define-logical-name", Fdefine_logical_name, Sdefine_logical_name,
       2, 2, "sDefine logical name: \nsDefine logical name %s as: ",
  "Define the job-wide logical name NAME to have the value STRING.\n\
If STRING is nil or a null string, the logical name NAME is deleted.")
  (varname, string)
     Lisp_Object varname;
     Lisp_Object string;
{
  CHECK_STRING (varname, 0);
Jim Blandy's avatar
Jim Blandy committed
1757
  if (NILP (string))
Jim Blandy's avatar
Jim Blandy committed
1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824
    delete_logical_name (XSTRING (varname)->data);
  else
    {
      CHECK_STRING (string, 1);

      if (XSTRING (string)->size == 0)
        delete_logical_name (XSTRING (varname)->data);
      else
        define_logical_name (XSTRING (varname)->data, XSTRING (string)->data);
    }

  return string;
}
#endif /* VMS */

#ifdef HPUX_NET

DEFUN ("sysnetunam", Fsysnetunam, Ssysnetunam, 2, 2, 0,
       "Open a network connection to PATH using LOGIN as the login string.")
     (path, login)
     Lisp_Object path, login;
{
  int netresult;
  
  CHECK_STRING (path, 0);
  CHECK_STRING (login, 0);  
  
  netresult = netunam (XSTRING (path)->data, XSTRING (login)->data);

  if (netresult == -1)
    return Qnil;
  else
    return Qt;
}
#endif /* HPUX_NET */

DEFUN ("file-name-absolute-p", Ffile_name_absolute_p, Sfile_name_absolute_p,
       1, 1, 0,
       "Return t if file FILENAME specifies an absolute path name.\n\
On Unix, this is a name starting with a `/' or a `~'.")
     (filename)
     Lisp_Object filename;
{
  unsigned char *ptr;

  CHECK_STRING (filename, 0);
  ptr = XSTRING (filename)->data;
  if (*ptr == '/' || *ptr == '~'
#ifdef VMS
/* ??? This criterion is probably wrong for '<'.  */
      || index (ptr, ':') || index (ptr, '<')
      || (*ptr == '[' && (ptr[1] != '-' || (ptr[2] != '.' && ptr[2] != ']'))
	  && ptr[1] != '.')
#endif /* VMS */
      )
    return Qt;
  else
    return Qnil;
}

DEFUN ("file-exists-p", Ffile_exists_p, Sfile_exists_p, 1, 1, 0,
  "Return t if file FILENAME exists.  (This does not mean you can read it.)\n\
See also `file-readable-p' and `file-attributes'.")
  (filename)
     Lisp_Object filename;
{
  Lisp_Object abspath;
1825
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1826 1827 1828

  CHECK_STRING (filename, 0);
  abspath = Fexpand_file_name (filename, Qnil);
1829 1830 1831 1832 1833 1834 1835

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call2 (handler, Qfile_exists_p, filename);

Jim Blandy's avatar
Jim Blandy committed
1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846
  return (access (XSTRING (abspath)->data, 0) >= 0) ? Qt : Qnil;
}

DEFUN ("file-executable-p", Ffile_executable_p, Sfile_executable_p, 1, 1, 0,
  "Return t if FILENAME can be executed by you.\n\
For directories this means you can change to that directory.")
  (filename)
    Lisp_Object filename;

{
  Lisp_Object abspath;
1847
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1848 1849 1850

  CHECK_STRING (filename, 0);
  abspath = Fexpand_file_name (filename, Qnil);
1851 1852 1853 1854 1855 1856 1857

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call2 (handler, Qfile_executable_p, filename);

Jim Blandy's avatar
Jim Blandy committed
1858 1859 1860 1861 1862 1863 1864 1865 1866 1867
  return (access (XSTRING (abspath)->data, 1) >= 0) ? Qt : Qnil;
}

DEFUN ("file-readable-p", Ffile_readable_p, Sfile_readable_p, 1, 1, 0,
  "Return t if file FILENAME exists and you can read it.\n\
See also `file-exists-p' and `file-attributes'.")
  (filename)
     Lisp_Object filename;
{
  Lisp_Object abspath;
1868
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1869 1870 1871

  CHECK_STRING (filename, 0);
  abspath = Fexpand_file_name (filename, Qnil);
1872 1873 1874 1875 1876 1877 1878

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call2 (handler, Qfile_readable_p, filename);

Jim Blandy's avatar
Jim Blandy committed
1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893
  return (access (XSTRING (abspath)->data, 4) >= 0) ? Qt : Qnil;
}

DEFUN ("file-symlink-p", Ffile_symlink_p, Sfile_symlink_p, 1, 1, 0,
  "If file FILENAME is the name of a symbolic link\n\
returns the name of the file to which it is linked.\n\
Otherwise returns NIL.")
  (filename)
     Lisp_Object filename;
{
#ifdef S_IFLNK
  char *buf;
  int bufsize;
  int valsize;
  Lisp_Object val;
1894
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1895 1896 1897 1898

  CHECK_STRING (filename, 0);
  filename = Fexpand_file_name (filename, Qnil);

1899 1900 1901 1902 1903 1904
  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call2 (handler, Qfile_symlink_p, filename);

Jim Blandy's avatar
Jim Blandy committed
1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936
  bufsize = 100;
  while (1)
    {
      buf = (char *) xmalloc (bufsize);
      bzero (buf, bufsize);
      valsize = readlink (XSTRING (filename)->data, buf, bufsize);
      if (valsize < bufsize) break;
      /* Buffer was not long enough */
      free (buf);
      bufsize *= 2;
    }
  if (valsize == -1)
    {
      free (buf);
      return Qnil;
    }
  val = make_string (buf, valsize);
  free (buf);
  return val;
#else /* not S_IFLNK */
  return Qnil;
#endif /* not S_IFLNK */
}

/* Having this before file-symlink-p mysteriously caused it to be forgotten
   on the RT/PC.  */
DEFUN ("file-writable-p", Ffile_writable_p, Sfile_writable_p, 1, 1, 0,
  "Return t if file FILENAME can be written or created by you.")
  (filename)
     Lisp_Object filename;
{
  Lisp_Object abspath, dir;
1937
  Lisp_Object handler;
Jim Blandy's avatar
Jim Blandy committed
1938 1939 1940

  CHECK_STRING (filename, 0);
  abspath = Fexpand_file_name (filename, Qnil);
1941 1942 1943 1944 1945 1946 1947

  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
  handler = find_file_handler (filename);
  if (!NILP (handler))
    return call2 (handler, Qfile_writable_p, filename);

Jim Blandy's avatar
Jim Blandy committed
1948 1949 1950 1951
  if (access (XSTRING (abspath)->data, 0) >= 0)
    return (access (XSTRING (abspath)->data, 2) >= 0) ? Qt : Qnil;
  dir = Ffile_name_directory (abspath);
#ifdef VMS
Jim Blandy's avatar
Jim Blandy committed
1952
  if (!NILP (dir))
Jim Blandy's avatar
Jim Blandy committed
1953 1954
    dir = Fdirectory_file_name (dir);
#endif /* VMS */
Jim Blandy's avatar
Jim Blandy committed
1955
  return (access (!NILP (dir) ? (char *) XSTRING (dir)->data : "", 2) >= 0
Jim Blandy's avatar
Jim Blandy committed
1956 1957