gcc/fortran/error.c

   1 /* Handle errors.
   2    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation,
   3    Inc.
   4    Contributed by Andy Vaught & Niels Kristian Bech Jensen
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING.  If not, write to the Free
  20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  21 02110-1301, USA.  */
  22
  23 /* Handle the inevitable errors.  A major catch here is that things
  24    flagged as errors in one match subroutine can conceivably be legal
  25    elsewhere.  This means that error messages are recorded and saved
  26    for possible use later.  If a line does not match a legal
  27    construction, then the saved error message is reported.  */
  28
  29 #include "config.h"
  30 #include "system.h"
  31 #include "flags.h"
  32 #include "gfortran.h"
  33
  34 int gfc_suppress_error = 0;
  35
  36 static int terminal_width, buffer_flag, errors, warnings;
  37
  38 static gfc_error_buf error_buffer, warning_buffer, *cur_error_buffer;
  39
  40
  41 /* Per-file error initialization.  */
  42
  43 void
  44 gfc_error_init_1 (void)
  45 {
  46   terminal_width = gfc_terminal_width ();
  47   errors = 0;
  48   warnings = 0;
  49   buffer_flag = 0;
  50 }
  51
  52
  53 /* Set the flag for buffering errors or not.  */
  54
  55 void
  56 gfc_buffer_error (int flag)
  57 {
  58   buffer_flag = flag;
  59 }
  60
  61
  62 /* Add a single character to the error buffer or output depending on
  63    buffer_flag.  */
  64
  65 static void
  66 error_char (char c)
  67 {
  68   if (buffer_flag)
  69     {
  70       if (cur_error_buffer->index >= cur_error_buffer->allocated)
  71         {
  72           cur_error_buffer->allocated =
  73             cur_error_buffer->allocated
  74             ? cur_error_buffer->allocated * 2 : 1000;
  75           cur_error_buffer->message
  76             = xrealloc (cur_error_buffer->message,
  77                         cur_error_buffer->allocated);
  78         }
  79       cur_error_buffer->message[cur_error_buffer->index++] = c;
  80     }
  81   else
  82     {
  83       if (c != 0)
  84         {
  85           /* We build up complete lines before handing things
  86              over to the library in order to speed up error printing.  */
  87           static char *line;
  88           static size_t allocated = 0, index = 0;
  89
  90           if (index + 1 >= allocated)
  91             {
  92               allocated = allocated ? allocated * 2 : 1000;
  93               line = xrealloc (line, allocated);
  94             }
  95           line[index++] = c;
  96           if (c == '\n')
  97             {
  98               line[index] = '\0';
  99               fputs (line, stderr);
 100               index = 0;
 101             }
 102         }
 103     }
 104 }
 105
 106
 107 /* Copy a string to wherever it needs to go.  */
 108
 109 static void
 110 error_string (const char *p)
 111 {
 112   while (*p)
 113     error_char (*p++);
 114 }
 115
 116
 117 /* Show the file, where it was included and the source line, give a
 118    locus.  Calls error_printf() recursively, but the recursion is at
 119    most one level deep.  */
 120
 121 static void error_printf (const char *, ...) ATTRIBUTE_GCC_GFC(1,2);
 122
 123 static void
 124 show_locus (int offset, locus * loc)
 125 {
 126   gfc_linebuf *lb;
 127   gfc_file *f;
 128   char c, *p;
 129   int i, m;
 130
 131   /* TODO: Either limit the total length and number of included files
 132      displayed or add buffering of arbitrary number of characters in
 133      error messages.  */
 134
 135   lb = loc->lb;
 136   f = lb->file;
 137   error_printf ("In file %s:%d\n", f->filename,
 138 #ifdef USE_MAPPED_LOCATION
 139                 LOCATION_LINE (lb->location)
 140 #else
 141                 lb->linenum
 142 #endif
 143                 );
 144
 145   for (;;)
 146     {
 147       i = f->inclusion_line;
 148
 149       f = f->included_by;
 150       if (f == NULL) break;
 151
 152       error_printf ("    Included at %s:%d\n", f->filename, i);
 153     }
 154
 155   /* Show the line itself, taking care not to print more than what can
 156      show up on the terminal.  Tabs are converted to spaces.  */
 157
 158   p = lb->line + offset;
 159   i = strlen (p);
 160   if (i > terminal_width)
 161     i = terminal_width - 1;
 162
 163   for (; i > 0; i--)
 164     {
 165       c = *p++;
 166       if (c == '\t')
 167         c = ' ';
 168
 169       if (ISPRINT (c))
 170         error_char (c);
 171       else
 172         {
 173           error_char ('\\');
 174           error_char ('x');
 175
 176           m = ((c >> 4) & 0x0F) + '0';
 177           if (m > '9')
 178             m += 'A' - '9' - 1;
 179           error_char (m);
 180
 181           m = (c & 0x0F) + '0';
 182           if (m > '9')
 183             m += 'A' - '9' - 1;
 184           error_char (m);
 185         }
 186     }
 187
 188   error_char ('\n');
 189 }
 190
 191
 192 /* As part of printing an error, we show the source lines that caused
 193    the problem.  We show at least one, possibly two loci.  If we're
 194    showing two loci and they both refer to the same file and line, we
 195    only print the line once.  */
 196
 197 static void
 198 show_loci (locus * l1, locus * l2)
 199 {
 200   int offset, flag, i, m, c1, c2, cmax;
 201
 202   if (l1 == NULL)
 203     {
 204       error_printf ("<During initialization>\n");
 205       return;
 206     }
 207
 208   c1 = l1->nextc - l1->lb->line;
 209   c2 = 0;
 210   if (l2 == NULL)
 211     goto separate;
 212
 213   c2 = l2->nextc - l2->lb->line;
 214
 215   if (c1 < c2)
 216     m = c2 - c1;
 217   else
 218     m = c1 - c2;
 219
 220
 221   if (l1->lb != l2->lb || m > terminal_width - 10)
 222     goto separate;
 223
 224   offset = 0;
 225   cmax = (c1 < c2) ? c2 : c1;
 226   if (cmax > terminal_width - 5)
 227     offset = cmax - terminal_width + 5;
 228
 229   if (offset < 0)
 230     offset = 0;
 231
 232   c1 -= offset;
 233   c2 -= offset;
 234
 235   show_locus (offset, l1);
 236
 237   /* Arrange that '1' and '2' will show up even if the two columns are equal.  */
 238   for (i = 1; i <= cmax; i++)
 239     {
 240       flag = 0;
 241       if (i == c1)
 242         {
 243           error_char ('1');
 244           flag = 1;
 245         }
 246       if (i == c2)
 247         {
 248           error_char ('2');
 249           flag = 1;
 250         }
 251       if (flag == 0)
 252         error_char (' ');
 253     }
 254
 255   error_char ('\n');
 256
 257   return;
 258
 259 separate:
 260   offset = 0;
 261
 262   if (c1 > terminal_width - 5)
 263     {
 264       offset = c1 - 5;
 265       if (offset < 0)
 266         offset = 0;
 267       c1 = c1 - offset;
 268     }
 269
 270   show_locus (offset, l1);
 271   for (i = 1; i < c1; i++)
 272     error_char (' ');
 273
 274   error_char ('1');
 275   error_char ('\n');
 276
 277   if (l2 != NULL)
 278     {
 279       offset = 0;
 280
 281       if (c2 > terminal_width - 20)
 282         {
 283           offset = c2 - 20;
 284           if (offset < 0)
 285             offset = 0;
 286           c2 = c2 - offset;
 287         }
 288
 289       show_locus (offset, l2);
 290
 291       for (i = 1; i < c2; i++)
 292         error_char (' ');
 293
 294       error_char ('2');
 295       error_char ('\n');
 296     }
 297 }
 298
 299
 300 /* Workhorse for the error printing subroutines.  This subroutine is
 301    inspired by g77's error handling and is similar to printf() with
 302    the following %-codes:
 303
 304    %c Character, %d Integer, %s String, %% Percent
 305    %L  Takes locus argument
 306    %C  Current locus (no argument)
 307
 308    If a locus pointer is given, the actual source line is printed out
 309    and the column is indicated.  Since we want the error message at
 310    the bottom of any source file information, we must scan the
 311    argument list twice.  A maximum of two locus arguments are
 312    permitted.  */
 313
 314 #define IBUF_LEN 30
 315 #define MAX_ARGS 10
 316
 317 static void ATTRIBUTE_GCC_GFC(2,0)
 318 error_print (const char *type, const char *format0, va_list argp)
 319 {
 320   char c, *p, int_buf[IBUF_LEN], c_arg[MAX_ARGS], *cp_arg[MAX_ARGS];
 321   int i, n, have_l1, i_arg[MAX_ARGS];
 322   locus *l1, *l2, *loc;
 323   const char *format;
 324
 325   l1 = l2 = loc = NULL;
 326
 327   have_l1 = 0;
 328
 329   n = 0;
 330   format = format0;
 331
 332   while (*format)
 333     {
 334       c = *format++;
 335       if (c == '%')
 336         {
 337           c = *format++;
 338
 339           switch (c)
 340             {
 341             case '%':
 342               break;
 343
 344             case 'L':
 345               loc = va_arg (argp, locus *);
 346               /* Fall through */
 347
 348             case 'C':
 349               if (c == 'C')
 350                 loc = &gfc_current_locus;
 351
 352               if (have_l1)
 353                 {
 354                   l2 = loc;
 355                 }
 356               else
 357                 {
 358                   l1 = loc;
 359                   have_l1 = 1;
 360                 }
 361               break;
 362
 363             case 'd':
 364             case 'i':
 365               i_arg[n++] = va_arg (argp, int);
 366               break;
 367
 368             case 'c':
 369               c_arg[n++] = va_arg (argp, int);
 370               break;
 371
 372             case 's':
 373               cp_arg[n++] = va_arg (argp, char *);
 374               break;
 375             }
 376         }
 377     }
 378
 379   /* Show the current loci if we have to.  */
 380   if (have_l1)
 381     show_loci (l1, l2);
 382   error_string (type);
 383   error_char (' ');
 384
 385   have_l1 = 0;
 386   format = format0;
 387   n = 0;
 388
 389   for (; *format; format++)
 390     {
 391       if (*format != '%')
 392         {
 393           error_char (*format);
 394           continue;
 395         }
 396
 397       format++;
 398       switch (*format)
 399         {
 400         case '%':
 401           error_char ('%');
 402           break;
 403
 404         case 'c':
 405           error_char (c_arg[n++]);
 406           break;
 407
 408         case 's':
 409           error_string (cp_arg[n++]);
 410           break;
 411
 412         case 'i':
 413         case 'd':
 414           i = i_arg[n++];
 415
 416           if (i < 0)
 417             {
 418               i = -i;
 419               error_char ('-');
 420             }
 421
 422           p = int_buf + IBUF_LEN - 1;
 423           *p-- = '\0';
 424
 425           if (i == 0)
 426             *p-- = '0';
 427
 428           while (i > 0)
 429             {
 430               *p-- = i % 10 + '0';
 431               i = i / 10;
 432             }
 433
 434           error_string (p + 1);
 435           break;
 436
 437         case 'C':               /* Current locus */
 438         case 'L':               /* Specified locus */
 439           error_string (have_l1 ? "(2)" : "(1)");
 440           have_l1 = 1;
 441           break;
 442         }
 443     }
 444
 445   error_char ('\n');
 446 }
 447
 448
 449 /* Wrapper for error_print().  */
 450
 451 static void
 452 error_printf (const char *nocmsgid, ...)
 453 {
 454   va_list argp;
 455
 456   va_start (argp, nocmsgid);
 457   error_print ("", _(nocmsgid), argp);
 458   va_end (argp);
 459 }
 460
 461
 462 /* Issue a warning.  */
 463
 464 void
 465 gfc_warning (const char *nocmsgid, ...)
 466 {
 467   va_list argp;
 468
 469   if (inhibit_warnings)
 470     return;
 471
 472   warning_buffer.flag = 1;
 473   warning_buffer.index = 0;
 474   cur_error_buffer = &warning_buffer;
 475
 476   va_start (argp, nocmsgid);
 477   if (buffer_flag == 0)
 478     warnings++;
 479   error_print (_("Warning:"), _(nocmsgid), argp);
 480   va_end (argp);
 481
 482   error_char ('\0');
 483 }
 484
 485
 486 /* Possibly issue a warning/error about use of a nonstandard (or deleted)
 487    feature.  An error/warning will be issued if the currently selected
 488    standard does not contain the requested bits.  Return FAILURE if
 489    an error is generated.  */
 490
 491 try
 492 gfc_notify_std (int std, const char *nocmsgid, ...)
 493 {
 494   va_list argp;
 495   bool warning;
 496
 497   warning = ((gfc_option.warn_std & std) != 0)
 498             && !inhibit_warnings;
 499   if ((gfc_option.allow_std & std) != 0
 500       && !warning)
 501     return SUCCESS;
 502
 503   if (gfc_suppress_error)
 504     return warning ? SUCCESS : FAILURE;
 505
 506   cur_error_buffer = warning ? &warning_buffer : &error_buffer;
 507   cur_error_buffer->flag = 1;
 508   cur_error_buffer->index = 0;
 509
 510   if (buffer_flag == 0)
 511     {
 512       if (warning)
 513         warnings++;
 514       else
 515         errors++;
 516     }
 517   va_start (argp, nocmsgid);
 518   if (warning)
 519     error_print (_("Warning:"), _(nocmsgid), argp);
 520   else
 521     error_print (_("Error:"), _(nocmsgid), argp);
 522   va_end (argp);
 523
 524   error_char ('\0');
 525   return warning ? SUCCESS : FAILURE;
 526 }
 527
 528
 529 /* Immediate warning (i.e. do not buffer the warning).  */
 530
 531 void
 532 gfc_warning_now (const char *nocmsgid, ...)
 533 {
 534   va_list argp;
 535   int i;
 536
 537   if (inhibit_warnings)
 538     return;
 539
 540   i = buffer_flag;
 541   buffer_flag = 0;
 542   warnings++;
 543
 544   va_start (argp, nocmsgid);
 545   error_print (_("Warning:"), _(nocmsgid), argp);
 546   va_end (argp);
 547
 548   error_char ('\0');
 549   buffer_flag = i;
 550 }
 551
 552
 553 /* Clear the warning flag.  */
 554
 555 void
 556 gfc_clear_warning (void)
 557 {
 558   warning_buffer.flag = 0;
 559 }
 560
 561
 562 /* Check to see if any warnings have been saved.
 563    If so, print the warning.  */
 564
 565 void
 566 gfc_warning_check (void)
 567 {
 568   if (warning_buffer.flag)
 569     {
 570       warnings++;
 571       if (warning_buffer.message != NULL)
 572         fputs (warning_buffer.message, stderr);
 573       warning_buffer.flag = 0;
 574     }
 575 }
 576
 577
 578 /* Issue an error.  */
 579
 580 void
 581 gfc_error (const char *nocmsgid, ...)
 582 {
 583   va_list argp;
 584
 585   if (gfc_suppress_error)
 586     return;
 587
 588   error_buffer.flag = 1;
 589   error_buffer.index = 0;
 590   cur_error_buffer = &error_buffer;
 591
 592   va_start (argp, nocmsgid);
 593   if (buffer_flag == 0)
 594     errors++;
 595   error_print (_("Error:"), _(nocmsgid), argp);
 596   va_end (argp);
 597
 598   error_char ('\0');
 599 }
 600
 601
 602 /* Immediate error.  */
 603
 604 void
 605 gfc_error_now (const char *nocmsgid, ...)
 606 {
 607   va_list argp;
 608   int i;
 609
 610   error_buffer.flag = 1;
 611   error_buffer.index = 0;
 612   cur_error_buffer = &error_buffer;
 613
 614   i = buffer_flag;
 615   buffer_flag = 0;
 616   errors++;
 617
 618   va_start (argp, nocmsgid);
 619   error_print (_("Error:"), _(nocmsgid), argp);
 620   va_end (argp);
 621
 622   error_char ('\0');
 623   buffer_flag = i;
 624
 625   if (flag_fatal_errors)
 626     exit (1);
 627 }
 628
 629
 630 /* Fatal error, never returns.  */
 631
 632 void
 633 gfc_fatal_error (const char *nocmsgid, ...)
 634 {
 635   va_list argp;
 636
 637   buffer_flag = 0;
 638
 639   va_start (argp, nocmsgid);
 640   error_print (_("Fatal Error:"), _(nocmsgid), argp);
 641   va_end (argp);
 642
 643   exit (3);
 644 }
 645
 646
 647 /* This shouldn't happen... but sometimes does.  */
 648
 649 void
 650 gfc_internal_error (const char *format, ...)
 651 {
 652   va_list argp;
 653
 654   buffer_flag = 0;
 655
 656   va_start (argp, format);
 657
 658   show_loci (&gfc_current_locus, NULL);
 659   error_printf ("Internal Error at (1):");
 660
 661   error_print ("", format, argp);
 662   va_end (argp);
 663
 664   exit (4);
 665 }
 666
 667
 668 /* Clear the error flag when we start to compile a source line.  */
 669
 670 void
 671 gfc_clear_error (void)
 672 {
 673   error_buffer.flag = 0;
 674 }
 675
 676
 677 /* Check to see if any errors have been saved.
 678    If so, print the error.  Returns the state of error_flag.  */
 679
 680 int
 681 gfc_error_check (void)
 682 {
 683   int rc;
 684
 685   rc = error_buffer.flag;
 686
 687   if (error_buffer.flag)
 688     {
 689       errors++;
 690       if (error_buffer.message != NULL)
 691         fputs (error_buffer.message, stderr);
 692       error_buffer.flag = 0;
 693
 694       if (flag_fatal_errors)
 695         exit (1);
 696     }
 697
 698   return rc;
 699 }
 700
 701
 702 /* Save the existing error state.  */
 703
 704 void
 705 gfc_push_error (gfc_error_buf * err)
 706 {
 707   err->flag = error_buffer.flag;
 708   if (error_buffer.flag)
 709     err->message = xstrdup (error_buffer.message);
 710
 711   error_buffer.flag = 0;
 712 }
 713
 714
 715 /* Restore a previous pushed error state.  */
 716
 717 void
 718 gfc_pop_error (gfc_error_buf * err)
 719 {
 720   error_buffer.flag = err->flag;
 721   if (error_buffer.flag)
 722     {
 723       size_t len = strlen (err->message) + 1;
 724       gcc_assert (len <= error_buffer.allocated);
 725       memcpy (error_buffer.message, err->message, len);
 726       gfc_free (err->message);
 727     }
 728 }
 729
 730
 731 /* Free a pushed error state, but keep the current error state.  */
 732
 733 void
 734 gfc_free_error (gfc_error_buf * err)
 735 {
 736   if (err->flag)
 737     gfc_free (err->message);
 738 }
 739
 740
 741 /* Debug wrapper for printf.  */
 742
 743 void
 744 gfc_status (const char *cmsgid, ...)
 745 {
 746   va_list argp;
 747
 748   va_start (argp, cmsgid);
 749
 750   vprintf (_(cmsgid), argp);
 751
 752   va_end (argp);
 753 }
 754
 755
 756 /* Subroutine for outputting a single char so that we don't have to go
 757    around creating a lot of 1-character strings.  */
 758
 759 void
 760 gfc_status_char (char c)
 761 {
 762   putchar (c);
 763 }
 764
 765
 766 /* Report the number of warnings and errors that occurred to the caller.  */
 767
 768 void
 769 gfc_get_errors (int *w, int *e)
 770 {
 771   if (w != NULL)
 772     *w = warnings;
 773   if (e != NULL)
 774     *e = errors;
 775 }