libgfortran/io/open.c

   1 /* Copyright (C) 2002-2014 Free Software Foundation, Inc.
   2    Contributed by Andy Vaught
   3    F2003 I/O support contributed by Jerry DeLisle
   4
   5 This file is part of the GNU Fortran runtime library (libgfortran).
   6
   7 Libgfortran is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 Libgfortran is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 Under Section 7 of GPL version 3, you are granted additional
  18 permissions described in the GCC Runtime Library Exception, version
  19 3.1, as published by the Free Software Foundation.
  20
  21 You should have received a copy of the GNU General Public License and
  22 a copy of the GCC Runtime Library Exception along with this program;
  23 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 <http://www.gnu.org/licenses/>.  */
  25
  26 #include "io.h"
  27 #include "fbuf.h"
  28 #include "unix.h"
  29
  30 #ifdef HAVE_UNISTD_H
  31 #include <unistd.h>
  32 #endif
  33
  34 #include <string.h>
  35 #include <errno.h>
  36 #include <stdlib.h>
  37
  38
  39 static const st_option access_opt[] = {
  40   {"sequential", ACCESS_SEQUENTIAL},
  41   {"direct", ACCESS_DIRECT},
  42   {"append", ACCESS_APPEND},
  43   {"stream", ACCESS_STREAM},
  44   {NULL, 0}
  45 };
  46
  47 static const st_option action_opt[] =
  48 {
  49   { "read", ACTION_READ},
  50   { "write", ACTION_WRITE},
  51   { "readwrite", ACTION_READWRITE},
  52   { NULL, 0}
  53 };
  54
  55 static const st_option blank_opt[] =
  56 {
  57   { "null", BLANK_NULL},
  58   { "zero", BLANK_ZERO},
  59   { NULL, 0}
  60 };
  61
  62 static const st_option delim_opt[] =
  63 {
  64   { "none", DELIM_NONE},
  65   { "apostrophe", DELIM_APOSTROPHE},
  66   { "quote", DELIM_QUOTE},
  67   { NULL, 0}
  68 };
  69
  70 static const st_option form_opt[] =
  71 {
  72   { "formatted", FORM_FORMATTED},
  73   { "unformatted", FORM_UNFORMATTED},
  74   { NULL, 0}
  75 };
  76
  77 static const st_option position_opt[] =
  78 {
  79   { "asis", POSITION_ASIS},
  80   { "rewind", POSITION_REWIND},
  81   { "append", POSITION_APPEND},
  82   { NULL, 0}
  83 };
  84
  85 static const st_option status_opt[] =
  86 {
  87   { "unknown", STATUS_UNKNOWN},
  88   { "old", STATUS_OLD},
  89   { "new", STATUS_NEW},
  90   { "replace", STATUS_REPLACE},
  91   { "scratch", STATUS_SCRATCH},
  92   { NULL, 0}
  93 };
  94
  95 static const st_option pad_opt[] =
  96 {
  97   { "yes", PAD_YES},
  98   { "no", PAD_NO},
  99   { NULL, 0}
 100 };
 101
 102 static const st_option decimal_opt[] =
 103 {
 104   { "point", DECIMAL_POINT},
 105   { "comma", DECIMAL_COMMA},
 106   { NULL, 0}
 107 };
 108
 109 static const st_option encoding_opt[] =
 110 {
 111   { "utf-8", ENCODING_UTF8},
 112   { "default", ENCODING_DEFAULT},
 113   { NULL, 0}
 114 };
 115
 116 static const st_option round_opt[] =
 117 {
 118   { "up", ROUND_UP},
 119   { "down", ROUND_DOWN},
 120   { "zero", ROUND_ZERO},
 121   { "nearest", ROUND_NEAREST},
 122   { "compatible", ROUND_COMPATIBLE},
 123   { "processor_defined", ROUND_PROCDEFINED},
 124   { NULL, 0}
 125 };
 126
 127 static const st_option sign_opt[] =
 128 {
 129   { "plus", SIGN_PLUS},
 130   { "suppress", SIGN_SUPPRESS},
 131   { "processor_defined", SIGN_PROCDEFINED},
 132   { NULL, 0}
 133 };
 134
 135 static const st_option convert_opt[] =
 136 {
 137   { "native", GFC_CONVERT_NATIVE},
 138   { "swap", GFC_CONVERT_SWAP},
 139   { "big_endian", GFC_CONVERT_BIG},
 140   { "little_endian", GFC_CONVERT_LITTLE},
 141   { NULL, 0}
 142 };
 143
 144 static const st_option async_opt[] =
 145 {
 146   { "yes", ASYNC_YES},
 147   { "no", ASYNC_NO},
 148   { NULL, 0}
 149 };
 150
 151 /* Given a unit, test to see if the file is positioned at the terminal
 152    point, and if so, change state from NO_ENDFILE flag to AT_ENDFILE.
 153    This prevents us from changing the state from AFTER_ENDFILE to
 154    AT_ENDFILE.  */
 155
 156 static void
 157 test_endfile (gfc_unit * u)
 158 {
 159   if (u->endfile == NO_ENDFILE)
 160     {
 161       gfc_offset sz = ssize (u->s);
 162       if (sz == 0 || sz == stell (u->s))
 163         u->endfile = AT_ENDFILE;
 164     }
 165 }
 166
 167
 168 /* Change the modes of a file, those that are allowed * to be
 169    changed.  */
 170
 171 static void
 172 edit_modes (st_parameter_open *opp, gfc_unit * u, unit_flags * flags)
 173 {
 174   /* Complain about attempts to change the unchangeable.  */
 175
 176   if (flags->status != STATUS_UNSPECIFIED && flags->status != STATUS_OLD &&
 177       u->flags.status != flags->status)
 178     generate_error (&opp->common, LIBERROR_BAD_OPTION,
 179                     "Cannot change STATUS parameter in OPEN statement");
 180
 181   if (flags->access != ACCESS_UNSPECIFIED && u->flags.access != flags->access)
 182     generate_error (&opp->common, LIBERROR_BAD_OPTION,
 183                     "Cannot change ACCESS parameter in OPEN statement");
 184
 185   if (flags->form != FORM_UNSPECIFIED && u->flags.form != flags->form)
 186     generate_error (&opp->common, LIBERROR_BAD_OPTION,
 187                     "Cannot change FORM parameter in OPEN statement");
 188
 189   if ((opp->common.flags & IOPARM_OPEN_HAS_RECL_IN)
 190       && opp->recl_in != u->recl)
 191     generate_error (&opp->common, LIBERROR_BAD_OPTION,
 192                     "Cannot change RECL parameter in OPEN statement");
 193
 194   if (flags->action != ACTION_UNSPECIFIED && u->flags.action != flags->action)
 195     generate_error (&opp->common, LIBERROR_BAD_OPTION,
 196                     "Cannot change ACTION parameter in OPEN statement");
 197
 198   /* Status must be OLD if present.  */
 199
 200   if (flags->status != STATUS_UNSPECIFIED && flags->status != STATUS_OLD &&
 201       flags->status != STATUS_UNKNOWN)
 202     {
 203       if (flags->status == STATUS_SCRATCH)
 204         notify_std (&opp->common, GFC_STD_GNU,
 205                     "OPEN statement must have a STATUS of OLD or UNKNOWN");
 206       else
 207         generate_error (&opp->common, LIBERROR_BAD_OPTION,
 208                     "OPEN statement must have a STATUS of OLD or UNKNOWN");
 209     }
 210
 211   if (u->flags.form == FORM_UNFORMATTED)
 212     {
 213       if (flags->delim != DELIM_UNSPECIFIED)
 214         generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 215                         "DELIM parameter conflicts with UNFORMATTED form in "
 216                         "OPEN statement");
 217
 218       if (flags->blank != BLANK_UNSPECIFIED)
 219         generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 220                         "BLANK parameter conflicts with UNFORMATTED form in "
 221                         "OPEN statement");
 222
 223       if (flags->pad != PAD_UNSPECIFIED)
 224         generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 225                         "PAD parameter conflicts with UNFORMATTED form in "
 226                         "OPEN statement");
 227
 228       if (flags->decimal != DECIMAL_UNSPECIFIED)
 229         generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 230                         "DECIMAL parameter conflicts with UNFORMATTED form in "
 231                         "OPEN statement");
 232
 233       if (flags->encoding != ENCODING_UNSPECIFIED)
 234         generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 235                         "ENCODING parameter conflicts with UNFORMATTED form in "
 236                         "OPEN statement");
 237
 238       if (flags->round != ROUND_UNSPECIFIED)
 239         generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 240                         "ROUND parameter conflicts with UNFORMATTED form in "
 241                         "OPEN statement");
 242
 243       if (flags->sign != SIGN_UNSPECIFIED)
 244         generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 245                         "SIGN parameter conflicts with UNFORMATTED form in "
 246                         "OPEN statement");
 247     }
 248
 249   if ((opp->common.flags & IOPARM_LIBRETURN_MASK) == IOPARM_LIBRETURN_OK)
 250     {
 251       /* Change the changeable:  */
 252       if (flags->blank != BLANK_UNSPECIFIED)
 253         u->flags.blank = flags->blank;
 254       if (flags->delim != DELIM_UNSPECIFIED)
 255         u->flags.delim = flags->delim;
 256       if (flags->pad != PAD_UNSPECIFIED)
 257         u->flags.pad = flags->pad;
 258       if (flags->decimal != DECIMAL_UNSPECIFIED)
 259         u->flags.decimal = flags->decimal;
 260       if (flags->encoding != ENCODING_UNSPECIFIED)
 261         u->flags.encoding = flags->encoding;
 262       if (flags->async != ASYNC_UNSPECIFIED)
 263         u->flags.async = flags->async;
 264       if (flags->round != ROUND_UNSPECIFIED)
 265         u->flags.round = flags->round;
 266       if (flags->sign != SIGN_UNSPECIFIED)
 267         u->flags.sign = flags->sign;
 268
 269       /* Reposition the file if necessary.  */
 270
 271       switch (flags->position)
 272         {
 273         case POSITION_UNSPECIFIED:
 274         case POSITION_ASIS:
 275           break;
 276
 277         case POSITION_REWIND:
 278           if (sseek (u->s, 0, SEEK_SET) != 0)
 279             goto seek_error;
 280
 281           u->current_record = 0;
 282           u->last_record = 0;
 283
 284           test_endfile (u);
 285           break;
 286
 287         case POSITION_APPEND:
 288           if (sseek (u->s, 0, SEEK_END) < 0)
 289             goto seek_error;
 290
 291           if (flags->access != ACCESS_STREAM)
 292             u->current_record = 0;
 293
 294           u->endfile = AT_ENDFILE;      /* We are at the end.  */
 295           break;
 296
 297         seek_error:
 298           generate_error (&opp->common, LIBERROR_OS, NULL);
 299           break;
 300         }
 301     }
 302
 303   unlock_unit (u);
 304 }
 305
 306
 307 /* Open an unused unit.  */
 308
 309 gfc_unit *
 310 new_unit (st_parameter_open *opp, gfc_unit *u, unit_flags * flags)
 311 {
 312   gfc_unit *u2;
 313   stream *s;
 314   char tmpname[5 /* fort. */ + 10 /* digits of unit number */ + 1 /* 0 */];
 315
 316   /* Change unspecifieds to defaults.  Leave (flags->action ==
 317      ACTION_UNSPECIFIED) alone so open_external() can set it based on
 318      what type of open actually works.  */
 319
 320   if (flags->access == ACCESS_UNSPECIFIED)
 321     flags->access = ACCESS_SEQUENTIAL;
 322
 323   if (flags->form == FORM_UNSPECIFIED)
 324     flags->form = (flags->access == ACCESS_SEQUENTIAL)
 325       ? FORM_FORMATTED : FORM_UNFORMATTED;
 326
 327   if (flags->async == ASYNC_UNSPECIFIED)
 328     flags->async = ASYNC_NO;
 329
 330   if (flags->status == STATUS_UNSPECIFIED)
 331     flags->status = STATUS_UNKNOWN;
 332
 333   /* Checks.  */
 334
 335   if (flags->delim != DELIM_UNSPECIFIED
 336       && flags->form == FORM_UNFORMATTED)
 337     {
 338       generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 339                       "DELIM parameter conflicts with UNFORMATTED form in "
 340                       "OPEN statement");
 341       goto fail;
 342     }
 343
 344   if (flags->blank == BLANK_UNSPECIFIED)
 345     flags->blank = BLANK_NULL;
 346   else
 347     {
 348       if (flags->form == FORM_UNFORMATTED)
 349         {
 350           generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 351                           "BLANK parameter conflicts with UNFORMATTED form in "
 352                           "OPEN statement");
 353           goto fail;
 354         }
 355     }
 356
 357   if (flags->pad == PAD_UNSPECIFIED)
 358     flags->pad = PAD_YES;
 359   else
 360     {
 361       if (flags->form == FORM_UNFORMATTED)
 362         {
 363           generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 364                           "PAD parameter conflicts with UNFORMATTED form in "
 365                           "OPEN statement");
 366           goto fail;
 367         }
 368     }
 369
 370   if (flags->decimal == DECIMAL_UNSPECIFIED)
 371     flags->decimal = DECIMAL_POINT;
 372   else
 373     {
 374       if (flags->form == FORM_UNFORMATTED)
 375         {
 376           generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 377                           "DECIMAL parameter conflicts with UNFORMATTED form "
 378                           "in OPEN statement");
 379           goto fail;
 380         }
 381     }
 382
 383   if (flags->encoding == ENCODING_UNSPECIFIED)
 384     flags->encoding = ENCODING_DEFAULT;
 385   else
 386     {
 387       if (flags->form == FORM_UNFORMATTED)
 388         {
 389           generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 390                           "ENCODING parameter conflicts with UNFORMATTED form in "
 391                           "OPEN statement");
 392           goto fail;
 393         }
 394     }
 395
 396   /* NB: the value for ROUND when it's not specified by the user does not
 397          have to be PROCESSOR_DEFINED; the standard says that it is
 398          processor dependent, and requires that it is one of the
 399          possible value (see F2003, 9.4.5.13).  */
 400   if (flags->round == ROUND_UNSPECIFIED)
 401     flags->round = ROUND_PROCDEFINED;
 402   else
 403     {
 404       if (flags->form == FORM_UNFORMATTED)
 405         {
 406           generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 407                           "ROUND parameter conflicts with UNFORMATTED form in "
 408                           "OPEN statement");
 409           goto fail;
 410         }
 411     }
 412
 413   if (flags->sign == SIGN_UNSPECIFIED)
 414     flags->sign = SIGN_PROCDEFINED;
 415   else
 416     {
 417       if (flags->form == FORM_UNFORMATTED)
 418         {
 419           generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 420                           "SIGN parameter conflicts with UNFORMATTED form in "
 421                           "OPEN statement");
 422           goto fail;
 423         }
 424     }
 425
 426   if (flags->position != POSITION_ASIS && flags->access == ACCESS_DIRECT)
 427    {
 428      generate_error (&opp->common, LIBERROR_OPTION_CONFLICT,
 429                      "ACCESS parameter conflicts with SEQUENTIAL access in "
 430                      "OPEN statement");
 431      goto fail;
 432    }
 433   else
 434    if (flags->position == POSITION_UNSPECIFIED)
 435      flags->position = POSITION_ASIS;
 436
 437   if (flags->access == ACCESS_DIRECT
 438       && (opp->common.flags & IOPARM_OPEN_HAS_RECL_IN) == 0)
 439     {
 440       generate_error (&opp->common, LIBERROR_MISSING_OPTION,
 441                       "Missing RECL parameter in OPEN statement");
 442       goto fail;
 443     }
 444
 445   if ((opp->common.flags & IOPARM_OPEN_HAS_RECL_IN) && opp->recl_in <= 0)
 446     {
 447       generate_error (&opp->common, LIBERROR_BAD_OPTION,
 448                       "RECL parameter is non-positive in OPEN statement");
 449       goto fail;
 450     }
 451
 452   switch (flags->status)
 453     {
 454     case STATUS_SCRATCH:
 455       if ((opp->common.flags & IOPARM_OPEN_HAS_FILE) == 0)
 456         {
 457           opp->file = NULL;
 458           break;
 459         }
 460
 461       generate_error (&opp->common, LIBERROR_BAD_OPTION,
 462                       "FILE parameter must not be present in OPEN statement");
 463       goto fail;
 464
 465     case STATUS_OLD:
 466     case STATUS_NEW:
 467     case STATUS_REPLACE:
 468     case STATUS_UNKNOWN:
 469       if ((opp->common.flags & IOPARM_OPEN_HAS_FILE))
 470         break;
 471
 472       opp->file = tmpname;
 473       opp->file_len = snprintf(opp->file, sizeof (tmpname), "fort.%d",
 474                                (int) opp->common.unit);
 475       break;
 476
 477     default:
 478       internal_error (&opp->common, "new_unit(): Bad status");
 479     }
 480
 481   /* Make sure the file isn't already open someplace else.
 482      Do not error if opening file preconnected to stdin, stdout, stderr.  */
 483
 484   u2 = NULL;
 485   if ((opp->common.flags & IOPARM_OPEN_HAS_FILE) != 0)
 486     u2 = find_file (opp->file, opp->file_len);
 487   if (u2 != NULL
 488       && (options.stdin_unit < 0 || u2->unit_number != options.stdin_unit)
 489       && (options.stdout_unit < 0 || u2->unit_number != options.stdout_unit)
 490       && (options.stderr_unit < 0 || u2->unit_number != options.stderr_unit))
 491     {
 492       unlock_unit (u2);
 493       generate_error (&opp->common, LIBERROR_ALREADY_OPEN, NULL);
 494       goto cleanup;
 495     }
 496
 497   if (u2 != NULL)
 498     unlock_unit (u2);
 499
 500   /* Open file.  */
 501
 502   s = open_external (opp, flags);
 503   if (s == NULL)
 504     {
 505       char *path = fc_strdup (opp->file, opp->file_len);
 506       size_t msglen = opp->file_len + 51;
 507       char *msg = xmalloc (msglen);
 508
 509       switch (errno)
 510         {
 511         case ENOENT:
 512           snprintf (msg, msglen, "File '%s' does not exist", path);
 513           break;
 514
 515         case EEXIST:
 516           snprintf (msg, msglen, "File '%s' already exists", path);
 517           break;
 518
 519         case EACCES:
 520           snprintf (msg, msglen,
 521                     "Permission denied trying to open file '%s'", path);
 522           break;
 523
 524         case EISDIR:
 525           snprintf (msg, msglen, "'%s' is a directory", path);
 526           break;
 527
 528         default:
 529           free (msg);
 530           msg = NULL;
 531         }
 532
 533       generate_error (&opp->common, LIBERROR_OS, msg);
 534       free (msg);
 535       free (path);
 536       goto cleanup;
 537     }
 538
 539   if (flags->status == STATUS_NEW || flags->status == STATUS_REPLACE)
 540     flags->status = STATUS_OLD;
 541
 542   /* Create the unit structure.  */
 543
 544   if (u->unit_number != opp->common.unit)
 545     internal_error (&opp->common, "Unit number changed");
 546   u->s = s;
 547   u->flags = *flags;
 548   u->read_bad = 0;
 549   u->endfile = NO_ENDFILE;
 550   u->last_record = 0;
 551   u->current_record = 0;
 552   u->mode = READING;
 553   u->maxrec = 0;
 554   u->bytes_left = 0;
 555   u->saved_pos = 0;
 556
 557   if (flags->position == POSITION_APPEND)
 558     {
 559       if (sseek (u->s, 0, SEEK_END) < 0)
 560         {
 561           generate_error (&opp->common, LIBERROR_OS, NULL);
 562           goto cleanup;
 563         }
 564       u->endfile = AT_ENDFILE;
 565     }
 566
 567   /* Unspecified recl ends up with a processor dependent value.  */
 568
 569   if ((opp->common.flags & IOPARM_OPEN_HAS_RECL_IN))
 570     {
 571       u->flags.has_recl = 1;
 572       u->recl = opp->recl_in;
 573       u->recl_subrecord = u->recl;
 574       u->bytes_left = u->recl;
 575     }
 576   else
 577     {
 578       u->flags.has_recl = 0;
 579       u->recl = max_offset;
 580       if (compile_options.max_subrecord_length)
 581         {
 582           u->recl_subrecord = compile_options.max_subrecord_length;
 583         }
 584       else
 585         {
 586           switch (compile_options.record_marker)
 587             {
 588             case 0:
 589               /* Fall through */
 590             case sizeof (GFC_INTEGER_4):
 591               u->recl_subrecord = GFC_MAX_SUBRECORD_LENGTH;
 592               break;
 593
 594             case sizeof (GFC_INTEGER_8):
 595               u->recl_subrecord = max_offset - 16;
 596               break;
 597
 598             default:
 599               runtime_error ("Illegal value for record marker");
 600               break;
 601             }
 602         }
 603     }
 604
 605   /* If the file is direct access, calculate the maximum record number
 606      via a division now instead of letting the multiplication overflow
 607      later.  */
 608
 609   if (flags->access == ACCESS_DIRECT)
 610     u->maxrec = max_offset / u->recl;
 611
 612   if (flags->access == ACCESS_STREAM)
 613     {
 614       u->maxrec = max_offset;
 615       u->recl = 1;
 616       u->bytes_left = 1;
 617       u->strm_pos = stell (u->s) + 1;
 618     }
 619
 620   u->filename = fc_strdup (opp->file, opp->file_len);
 621
 622   /* Curiously, the standard requires that the
 623      position specifier be ignored for new files so a newly connected
 624      file starts out at the initial point.  We still need to figure
 625      out if the file is at the end or not.  */
 626
 627   test_endfile (u);
 628
 629   if (flags->status == STATUS_SCRATCH && opp->file != NULL)
 630     free (opp->file);
 631
 632   if (flags->form == FORM_FORMATTED)
 633     {
 634       if ((opp->common.flags & IOPARM_OPEN_HAS_RECL_IN))
 635         fbuf_init (u, u->recl);
 636       else
 637         fbuf_init (u, 0);
 638     }
 639   else
 640     u->fbuf = NULL;
 641
 642
 643
 644   return u;
 645
 646  cleanup:
 647
 648   /* Free memory associated with a temporary filename.  */
 649
 650   if (flags->status == STATUS_SCRATCH && opp->file != NULL)
 651     free (opp->file);
 652
 653  fail:
 654
 655   close_unit (u);
 656   return NULL;
 657 }
 658
 659
 660 /* Open a unit which is already open.  This involves changing the
 661    modes or closing what is there now and opening the new file.  */
 662
 663 static void
 664 already_open (st_parameter_open *opp, gfc_unit * u, unit_flags * flags)
 665 {
 666   if ((opp->common.flags & IOPARM_OPEN_HAS_FILE) == 0)
 667     {
 668       edit_modes (opp, u, flags);
 669       return;
 670     }
 671
 672   /* If the file is connected to something else, close it and open a
 673      new unit.  */
 674
 675   if (!compare_file_filename (u, opp->file, opp->file_len))
 676     {
 677       if (sclose (u->s) == -1)
 678         {
 679           unlock_unit (u);
 680           generate_error (&opp->common, LIBERROR_OS,
 681                           "Error closing file in OPEN statement");
 682           return;
 683         }
 684
 685       u->s = NULL;
 686
 687 #if !HAVE_UNLINK_OPEN_FILE
 688       if (u->filename && u->flags.status == STATUS_SCRATCH)
 689         unlink (u->filename);
 690 #endif
 691      free (u->filename);
 692      u->filename = NULL;
 693
 694       u = new_unit (opp, u, flags);
 695       if (u != NULL)
 696         unlock_unit (u);
 697       return;
 698     }
 699
 700   edit_modes (opp, u, flags);
 701 }
 702
 703
 704 /* Open file.  */
 705
 706 extern void st_open (st_parameter_open *opp);
 707 export_proto(st_open);
 708
 709 void
 710 st_open (st_parameter_open *opp)
 711 {
 712   unit_flags flags;
 713   gfc_unit *u = NULL;
 714   GFC_INTEGER_4 cf = opp->common.flags;
 715   unit_convert conv;
 716
 717   library_start (&opp->common);
 718
 719   /* Decode options.  */
 720
 721   flags.access = !(cf & IOPARM_OPEN_HAS_ACCESS) ? ACCESS_UNSPECIFIED :
 722     find_option (&opp->common, opp->access, opp->access_len,
 723                  access_opt, "Bad ACCESS parameter in OPEN statement");
 724
 725   flags.action = !(cf & IOPARM_OPEN_HAS_ACTION) ? ACTION_UNSPECIFIED :
 726     find_option (&opp->common, opp->action, opp->action_len,
 727                  action_opt, "Bad ACTION parameter in OPEN statement");
 728
 729   flags.blank = !(cf & IOPARM_OPEN_HAS_BLANK) ? BLANK_UNSPECIFIED :
 730     find_option (&opp->common, opp->blank, opp->blank_len,
 731                  blank_opt, "Bad BLANK parameter in OPEN statement");
 732
 733   flags.delim = !(cf & IOPARM_OPEN_HAS_DELIM) ? DELIM_UNSPECIFIED :
 734     find_option (&opp->common, opp->delim, opp->delim_len,
 735                  delim_opt, "Bad DELIM parameter in OPEN statement");
 736
 737   flags.pad = !(cf & IOPARM_OPEN_HAS_PAD) ? PAD_UNSPECIFIED :
 738     find_option (&opp->common, opp->pad, opp->pad_len,
 739                  pad_opt, "Bad PAD parameter in OPEN statement");
 740
 741   flags.decimal = !(cf & IOPARM_OPEN_HAS_DECIMAL) ? DECIMAL_UNSPECIFIED :
 742     find_option (&opp->common, opp->decimal, opp->decimal_len,
 743                  decimal_opt, "Bad DECIMAL parameter in OPEN statement");
 744
 745   flags.encoding = !(cf & IOPARM_OPEN_HAS_ENCODING) ? ENCODING_UNSPECIFIED :
 746     find_option (&opp->common, opp->encoding, opp->encoding_len,
 747                  encoding_opt, "Bad ENCODING parameter in OPEN statement");
 748
 749   flags.async = !(cf & IOPARM_OPEN_HAS_ASYNCHRONOUS) ? ASYNC_UNSPECIFIED :
 750     find_option (&opp->common, opp->asynchronous, opp->asynchronous_len,
 751                  async_opt, "Bad ASYNCHRONOUS parameter in OPEN statement");
 752
 753   flags.round = !(cf & IOPARM_OPEN_HAS_ROUND) ? ROUND_UNSPECIFIED :
 754     find_option (&opp->common, opp->round, opp->round_len,
 755                  round_opt, "Bad ROUND parameter in OPEN statement");
 756
 757   flags.sign = !(cf & IOPARM_OPEN_HAS_SIGN) ? SIGN_UNSPECIFIED :
 758     find_option (&opp->common, opp->sign, opp->sign_len,
 759                  sign_opt, "Bad SIGN parameter in OPEN statement");
 760
 761   flags.form = !(cf & IOPARM_OPEN_HAS_FORM) ? FORM_UNSPECIFIED :
 762     find_option (&opp->common, opp->form, opp->form_len,
 763                  form_opt, "Bad FORM parameter in OPEN statement");
 764
 765   flags.position = !(cf & IOPARM_OPEN_HAS_POSITION) ? POSITION_UNSPECIFIED :
 766     find_option (&opp->common, opp->position, opp->position_len,
 767                  position_opt, "Bad POSITION parameter in OPEN statement");
 768
 769   flags.status = !(cf & IOPARM_OPEN_HAS_STATUS) ? STATUS_UNSPECIFIED :
 770     find_option (&opp->common, opp->status, opp->status_len,
 771                  status_opt, "Bad STATUS parameter in OPEN statement");
 772
 773   /* First, we check wether the convert flag has been set via environment
 774      variable.  This overrides the convert tag in the open statement.  */
 775
 776   conv = get_unformatted_convert (opp->common.unit);
 777
 778   if (conv == GFC_CONVERT_NONE)
 779     {
 780       /* Nothing has been set by environment variable, check the convert tag.  */
 781       if (cf & IOPARM_OPEN_HAS_CONVERT)
 782         conv = find_option (&opp->common, opp->convert, opp->convert_len,
 783                             convert_opt,
 784                             "Bad CONVERT parameter in OPEN statement");
 785       else
 786         conv = compile_options.convert;
 787     }
 788
 789   /* We use big_endian, which is 0 on little-endian machines
 790      and 1 on big-endian machines.  */
 791   switch (conv)
 792     {
 793     case GFC_CONVERT_NATIVE:
 794     case GFC_CONVERT_SWAP:
 795       break;
 796
 797     case GFC_CONVERT_BIG:
 798       conv = big_endian ? GFC_CONVERT_NATIVE : GFC_CONVERT_SWAP;
 799       break;
 800
 801     case GFC_CONVERT_LITTLE:
 802       conv = big_endian ? GFC_CONVERT_SWAP : GFC_CONVERT_NATIVE;
 803       break;
 804
 805     default:
 806       internal_error (&opp->common, "Illegal value for CONVERT");
 807       break;
 808     }
 809
 810   flags.convert = conv;
 811
 812   if (flags.position != POSITION_UNSPECIFIED
 813       && flags.access == ACCESS_DIRECT)
 814     generate_error (&opp->common, LIBERROR_BAD_OPTION,
 815                     "Cannot use POSITION with direct access files");
 816
 817   if (flags.access == ACCESS_APPEND)
 818     {
 819       if (flags.position != POSITION_UNSPECIFIED
 820           && flags.position != POSITION_APPEND)
 821         generate_error (&opp->common, LIBERROR_BAD_OPTION,
 822                         "Conflicting ACCESS and POSITION flags in"
 823                         " OPEN statement");
 824
 825       notify_std (&opp->common, GFC_STD_GNU,
 826                   "Extension: APPEND as a value for ACCESS in OPEN statement");
 827       flags.access = ACCESS_SEQUENTIAL;
 828       flags.position = POSITION_APPEND;
 829     }
 830
 831   if (flags.position == POSITION_UNSPECIFIED)
 832     flags.position = POSITION_ASIS;
 833
 834   if ((opp->common.flags & IOPARM_LIBRETURN_MASK) == IOPARM_LIBRETURN_OK)
 835     {
 836       if ((opp->common.flags & IOPARM_OPEN_HAS_NEWUNIT))
 837         opp->common.unit = get_unique_unit_number(opp);
 838       else if (opp->common.unit < 0)
 839         {
 840           u = find_unit (opp->common.unit);
 841           if (u == NULL) /* Negative unit and no NEWUNIT-created unit found.  */
 842             {
 843               generate_error (&opp->common, LIBERROR_BAD_OPTION,
 844                               "Bad unit number in OPEN statement");
 845               library_end ();
 846               return;
 847             }
 848         }
 849
 850       if (u == NULL)
 851         u = find_or_create_unit (opp->common.unit);
 852       if (u->s == NULL)
 853         {
 854           u = new_unit (opp, u, &flags);
 855           if (u != NULL)
 856             unlock_unit (u);
 857         }
 858       else
 859         already_open (opp, u, &flags);
 860     }
 861
 862   if ((opp->common.flags & IOPARM_OPEN_HAS_NEWUNIT)
 863       && (opp->common.flags & IOPARM_LIBRETURN_MASK) == IOPARM_LIBRETURN_OK)
 864     *opp->newunit = opp->common.unit;
 865
 866   library_end ();
 867 }