ld/ldfile.c

   1 /* Linker file opening and searching.
   2    Copyright 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2000, 2001, 2002,
   3    2003, 2004, 2005, 2007, 2008 Free Software Foundation, Inc.
   4
   5    This file is part of the GNU Binutils.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  20    MA 02110-1301, USA.  */
  21
  22 #include "sysdep.h"
  23 #include "bfd.h"
  24 #include "bfdlink.h"
  25 #include "safe-ctype.h"
  26 #include "ld.h"
  27 #include "ldmisc.h"
  28 #include "ldexp.h"
  29 #include "ldlang.h"
  30 #include "ldfile.h"
  31 #include "ldmain.h"
  32 #include <ldgram.h>
  33 #include "ldlex.h"
  34 #include "ldemul.h"
  35 #include "libiberty.h"
  36 #include "filenames.h"
  37
  38 const char * ldfile_input_filename;
  39 bfd_boolean  ldfile_assumed_script = FALSE;
  40 const char * ldfile_output_machine_name = "";
  41 unsigned long ldfile_output_machine;
  42 enum bfd_architecture ldfile_output_architecture;
  43 search_dirs_type * search_head;
  44
  45 #ifdef VMS
  46 static char * slash = "";
  47 #else
  48 #if defined (_WIN32) && ! defined (__CYGWIN32__)
  49 static char * slash = "\\";
  50 #else
  51 static char * slash = "/";
  52 #endif
  53 #endif
  54
  55 typedef struct search_arch
  56 {
  57   char *name;
  58   struct search_arch *next;
  59 } search_arch_type;
  60
  61 static search_dirs_type **search_tail_ptr = &search_head;
  62 static search_arch_type *search_arch_head;
  63 static search_arch_type **search_arch_tail_ptr = &search_arch_head;
  64
  65 /* Test whether a pathname, after canonicalization, is the same or a
  66    sub-directory of the sysroot directory.  */
  67
  68 static bfd_boolean
  69 is_sysrooted_pathname (const char *name, bfd_boolean notsame)
  70 {
  71   char * realname = ld_canon_sysroot ? lrealpath (name) : NULL;
  72   int len;
  73   bfd_boolean result;
  74
  75   if (! realname)
  76     return FALSE;
  77
  78   len = strlen (realname);
  79
  80   if (((! notsame && len == ld_canon_sysroot_len)
  81        || (len >= ld_canon_sysroot_len
  82            && IS_DIR_SEPARATOR (realname[ld_canon_sysroot_len])
  83            && (realname[ld_canon_sysroot_len] = '\0') == '\0'))
  84       && FILENAME_CMP (ld_canon_sysroot, realname) == 0)
  85     result = TRUE;
  86   else
  87     result = FALSE;
  88
  89   if (realname)
  90     free (realname);
  91
  92   return result;
  93 }
  94
  95 /* Adds NAME to the library search path.
  96    Makes a copy of NAME using xmalloc().  */
  97
  98 void
  99 ldfile_add_library_path (const char *name, bfd_boolean cmdline)
 100 {
 101   search_dirs_type *new;
 102
 103   if (!cmdline && config.only_cmd_line_lib_dirs)
 104     return;
 105
 106   new = xmalloc (sizeof (search_dirs_type));
 107   new->next = NULL;
 108   new->cmdline = cmdline;
 109   *search_tail_ptr = new;
 110   search_tail_ptr = &new->next;
 111
 112   /* If a directory is marked as honoring sysroot, prepend the sysroot path
 113      now.  */
 114   if (name[0] == '=')
 115     {
 116       new->name = concat (ld_sysroot, name + 1, (const char *) NULL);
 117       new->sysrooted = TRUE;
 118     }
 119   else
 120     {
 121       new->name = xstrdup (name);
 122       new->sysrooted = is_sysrooted_pathname (name, FALSE);
 123     }
 124 }
 125
 126 /* Try to open a BFD for a lang_input_statement.  */
 127
 128 bfd_boolean
 129 ldfile_try_open_bfd (const char *attempt,
 130                      lang_input_statement_type *entry)
 131 {
 132   entry->the_bfd = bfd_openr (attempt, entry->target);
 133
 134   if (trace_file_tries)
 135     {
 136       if (entry->the_bfd == NULL)
 137         info_msg (_("attempt to open %s failed\n"), attempt);
 138       else
 139         info_msg (_("attempt to open %s succeeded\n"), attempt);
 140     }
 141
 142   if (entry->the_bfd == NULL)
 143     {
 144       if (bfd_get_error () == bfd_error_invalid_target)
 145         einfo (_("%F%P: invalid BFD target `%s'\n"), entry->target);
 146       return FALSE;
 147     }
 148
 149   /* If we are searching for this file, see if the architecture is
 150      compatible with the output file.  If it isn't, keep searching.
 151      If we can't open the file as an object file, stop the search
 152      here.  If we are statically linking, ensure that we don't link
 153      a dynamic object.  */
 154
 155   if (entry->search_dirs_flag || !entry->dynamic)
 156     {
 157       bfd *check;
 158
 159       if (bfd_check_format (entry->the_bfd, bfd_archive))
 160         check = bfd_openr_next_archived_file (entry->the_bfd, NULL);
 161       else
 162         check = entry->the_bfd;
 163
 164       if (check != NULL)
 165         {
 166           if (! bfd_check_format (check, bfd_object))
 167             {
 168               if (check == entry->the_bfd
 169                   && entry->search_dirs_flag
 170                   && bfd_get_error () == bfd_error_file_not_recognized
 171                   && ! ldemul_unrecognized_file (entry))
 172                 {
 173                   int token, skip = 0;
 174                   char *arg, *arg1, *arg2, *arg3;
 175                   extern FILE *yyin;
 176
 177                   /* Try to interpret the file as a linker script.  */
 178                   ldfile_open_command_file (attempt);
 179
 180                   ldfile_assumed_script = TRUE;
 181                   parser_input = input_selected;
 182                   ldlex_both ();
 183                   token = INPUT_SCRIPT;
 184                   while (token != 0)
 185                     {
 186                       switch (token)
 187                         {
 188                         case OUTPUT_FORMAT:
 189                           if ((token = yylex ()) != '(')
 190                             continue;
 191                           if ((token = yylex ()) != NAME)
 192                             continue;
 193                           arg1 = yylval.name;
 194                           arg2 = NULL;
 195                           arg3 = NULL;
 196                           token = yylex ();
 197                           if (token == ',')
 198                             {
 199                               if ((token = yylex ()) != NAME)
 200                                 {
 201                                   free (arg1);
 202                                   continue;
 203                                 }
 204                               arg2 = yylval.name;
 205                               if ((token = yylex ()) != ','
 206                                   || (token = yylex ()) != NAME)
 207                                 {
 208                                   free (arg1);
 209                                   free (arg2);
 210                                   continue;
 211                                 }
 212                               arg3 = yylval.name;
 213                               token = yylex ();
 214                             }
 215                           if (token == ')')
 216                             {
 217                               switch (command_line.endian)
 218                                 {
 219                                 default:
 220                                 case ENDIAN_UNSET:
 221                                   arg = arg1; break;
 222                                 case ENDIAN_BIG:
 223                                   arg = arg2 ? arg2 : arg1; break;
 224                                 case ENDIAN_LITTLE:
 225                                   arg = arg3 ? arg3 : arg1; break;
 226                                 }
 227                               if (strcmp (arg, lang_get_output_target ()) != 0)
 228                                 skip = 1;
 229                             }
 230                           free (arg1);
 231                           if (arg2) free (arg2);
 232                           if (arg3) free (arg3);
 233                           break;
 234                         case NAME:
 235                         case LNAME:
 236                         case VERS_IDENTIFIER:
 237                         case VERS_TAG:
 238                           free (yylval.name);
 239                           break;
 240                         case INT:
 241                           if (yylval.bigint.str)
 242                             free (yylval.bigint.str);
 243                           break;
 244                         }
 245                       token = yylex ();
 246                     }
 247                   ldlex_popstate ();
 248                   ldfile_assumed_script = FALSE;
 249                   fclose (yyin);
 250                   yyin = NULL;
 251                   if (skip)
 252                     {
 253                       if (command_line.warn_search_mismatch)
 254                         einfo (_("%P: skipping incompatible %s "
 255                                  "when searching for %s\n"),
 256                                attempt, entry->local_sym_name);
 257                       bfd_close (entry->the_bfd);
 258                       entry->the_bfd = NULL;
 259                       return FALSE;
 260                     }
 261                 }
 262               return TRUE;
 263             }
 264
 265           if (!entry->dynamic && (entry->the_bfd->flags & DYNAMIC) != 0)
 266             {
 267               einfo (_("%F%P: attempted static link of dynamic object `%s'\n"),
 268                      attempt);
 269               bfd_close (entry->the_bfd);
 270               entry->the_bfd = NULL;
 271               return FALSE;
 272             }
 273
 274           if (entry->search_dirs_flag
 275               && !bfd_arch_get_compatible (check, link_info.output_bfd,
 276                                            command_line.accept_unknown_input_arch)
 277               /* XCOFF archives can have 32 and 64 bit objects.  */
 278               && ! (bfd_get_flavour (check) == bfd_target_xcoff_flavour
 279                     && bfd_get_flavour (link_info.output_bfd) == bfd_target_xcoff_flavour
 280                     && bfd_check_format (entry->the_bfd, bfd_archive)))
 281             {
 282               if (command_line.warn_search_mismatch)
 283                 einfo (_("%P: skipping incompatible %s "
 284                          "when searching for %s\n"),
 285                        attempt, entry->local_sym_name);
 286               bfd_close (entry->the_bfd);
 287               entry->the_bfd = NULL;
 288               return FALSE;
 289             }
 290         }
 291     }
 292
 293   return TRUE;
 294 }
 295
 296 /* Search for and open the file specified by ENTRY.  If it is an
 297    archive, use ARCH, LIB and SUFFIX to modify the file name.  */
 298
 299 bfd_boolean
 300 ldfile_open_file_search (const char *arch,
 301                          lang_input_statement_type *entry,
 302                          const char *lib,
 303                          const char *suffix)
 304 {
 305   search_dirs_type *search;
 306
 307   /* If this is not an archive, try to open it in the current
 308      directory first.  */
 309   if (! entry->is_archive)
 310     {
 311       if (entry->sysrooted && IS_ABSOLUTE_PATH (entry->filename))
 312         {
 313           char *name = concat (ld_sysroot, entry->filename,
 314                                (const char *) NULL);
 315           if (ldfile_try_open_bfd (name, entry))
 316             {
 317               entry->filename = name;
 318               return TRUE;
 319             }
 320           free (name);
 321         }
 322       else if (ldfile_try_open_bfd (entry->filename, entry))
 323         {
 324           entry->sysrooted = IS_ABSOLUTE_PATH (entry->filename)
 325             && is_sysrooted_pathname (entry->filename, TRUE);
 326           return TRUE;
 327         }
 328
 329       if (IS_ABSOLUTE_PATH (entry->filename))
 330         return FALSE;
 331     }
 332
 333   for (search = search_head; search != NULL; search = search->next)
 334     {
 335       char *string;
 336
 337       if (entry->dynamic && ! link_info.relocatable)
 338         {
 339           if (ldemul_open_dynamic_archive (arch, search, entry))
 340             {
 341               entry->sysrooted = search->sysrooted;
 342               return TRUE;
 343             }
 344         }
 345
 346       if (entry->is_archive)
 347         string = concat (search->name, slash, lib, entry->filename,
 348                          arch, suffix, (const char *) NULL);
 349       else
 350         string = concat (search->name, slash, entry->filename,
 351                          (const char *) 0);
 352
 353       if (ldfile_try_open_bfd (string, entry))
 354         {
 355           entry->filename = string;
 356           entry->sysrooted = search->sysrooted;
 357           return TRUE;
 358         }
 359
 360       free (string);
 361     }
 362
 363   return FALSE;
 364 }
 365
 366 /* Open the input file specified by ENTRY.  */
 367
 368 void
 369 ldfile_open_file (lang_input_statement_type *entry)
 370 {
 371   if (entry->the_bfd != NULL)
 372     return;
 373
 374   if (! entry->search_dirs_flag)
 375     {
 376       if (ldfile_try_open_bfd (entry->filename, entry))
 377         return;
 378       if (strcmp (entry->filename, entry->local_sym_name) != 0)
 379         einfo (_("%F%P: %s (%s): No such file: %E\n"),
 380                entry->filename, entry->local_sym_name);
 381       else
 382         einfo (_("%F%P: %s: No such file: %E\n"), entry->local_sym_name);
 383     }
 384   else
 385     {
 386       search_arch_type *arch;
 387       bfd_boolean found = FALSE;
 388
 389       /* Try to open <filename><suffix> or lib<filename><suffix>.a */
 390       for (arch = search_arch_head; arch != NULL; arch = arch->next)
 391         {
 392           found = ldfile_open_file_search (arch->name, entry, "lib", ".a");
 393           if (found)
 394             break;
 395 #ifdef VMS
 396           found = ldfile_open_file_search (arch->name, entry, ":lib", ".a");
 397           if (found)
 398             break;
 399 #endif
 400           found = ldemul_find_potential_libraries (arch->name, entry);
 401           if (found)
 402             break;
 403         }
 404
 405       /* If we have found the file, we don't need to search directories
 406          again.  */
 407       if (found)
 408         entry->search_dirs_flag = FALSE;
 409       else if (entry->sysrooted
 410                && ld_sysroot
 411                && IS_ABSOLUTE_PATH (entry->local_sym_name))
 412         einfo (_("%F%P: cannot find %s inside %s\n"),
 413                entry->local_sym_name, ld_sysroot);
 414       else
 415         einfo (_("%F%P: cannot find %s\n"), entry->local_sym_name);
 416     }
 417 }
 418
 419 /* Try to open NAME; if that fails, try NAME with EXTEN appended to it.  */
 420
 421 static FILE *
 422 try_open (const char *name, const char *exten)
 423 {
 424   FILE *result;
 425
 426   result = fopen (name, "r");
 427
 428   if (trace_file_tries)
 429     {
 430       if (result == NULL)
 431         info_msg (_("cannot find script file %s\n"), name);
 432       else
 433         info_msg (_("opened script file %s\n"), name);
 434     }
 435
 436   if (result != NULL)
 437     return result;
 438
 439   if (*exten)
 440     {
 441       char *buff;
 442
 443       buff = concat (name, exten, (const char *) NULL);
 444       result = fopen (buff, "r");
 445
 446       if (trace_file_tries)
 447         {
 448           if (result == NULL)
 449             info_msg (_("cannot find script file %s\n"), buff);
 450           else
 451             info_msg (_("opened script file %s\n"), buff);
 452         }
 453       free (buff);
 454     }
 455
 456   return result;
 457 }
 458
 459 /* Return TRUE iff directory DIR contains an "ldscripts" subdirectory.  */
 460
 461 static bfd_boolean
 462 check_for_scripts_dir (char *dir)
 463 {
 464   char *buf;
 465   struct stat s;
 466   bfd_boolean res;
 467
 468   buf = concat (dir, "/ldscripts", (const char *) NULL);
 469   res = stat (buf, &s) == 0 && S_ISDIR (s.st_mode);
 470   free (buf);
 471   return res;
 472 }
 473
 474 /* Return the default directory for finding script files.
 475    We look for the "ldscripts" directory in:
 476
 477    SCRIPTDIR (passed from Makefile)
 478              (adjusted according to the current location of the binary)
 479    SCRIPTDIR (passed from Makefile)
 480    the dir where this program is (for using it from the build tree)
 481    the dir where this program is/../lib
 482              (for installing the tool suite elsewhere).  */
 483
 484 static char *
 485 find_scripts_dir (void)
 486 {
 487   char *end, *dir;
 488   size_t dirlen;
 489
 490   dir = make_relative_prefix (program_name, BINDIR, SCRIPTDIR);
 491   if (dir)
 492     {
 493       if (check_for_scripts_dir (dir))
 494         return dir;
 495       free (dir);
 496     }
 497
 498   dir = make_relative_prefix (program_name, TOOLBINDIR, SCRIPTDIR);
 499   if (dir)
 500     {
 501       if (check_for_scripts_dir (dir))
 502         return dir;
 503       free (dir);
 504     }
 505
 506   if (check_for_scripts_dir (SCRIPTDIR))
 507     /* We've been installed normally.  */
 508     return SCRIPTDIR;
 509
 510   /* Look for "ldscripts" in the dir where our binary is.  */
 511   end = strrchr (program_name, '/');
 512 #ifdef HAVE_DOS_BASED_FILE_SYSTEM
 513   {
 514     /* We could have \foo\bar, or /foo\bar.  */
 515     char *bslash = strrchr (program_name, '\\');
 516
 517     if (end == NULL || (bslash != NULL && bslash > end))
 518       end = bslash;
 519   }
 520 #endif
 521
 522   if (end == NULL)
 523     /* Don't look for ldscripts in the current directory.  There is
 524        too much potential for confusion.  */
 525     return NULL;
 526
 527   dirlen = end - program_name;
 528   /* Make a copy of program_name in dir.
 529      Leave room for later "/../lib".  */
 530   dir = xmalloc (dirlen + sizeof ("/../lib"));
 531   strncpy (dir, program_name, dirlen);
 532   dir[dirlen] = '\0';
 533
 534   if (check_for_scripts_dir (dir))
 535     return dir;
 536
 537   /* Look for "ldscripts" in <the dir where our binary is>/../lib.  */
 538   strcpy (dir + dirlen, "/../lib");
 539   if (check_for_scripts_dir (dir))
 540     return dir;
 541   free (dir);
 542   return NULL;
 543 }
 544
 545 /* Try to open NAME; if that fails, look for it in the default script
 546    directory, then in any directories specified with -L, without and
 547    with EXTEND appended.  */
 548
 549 static FILE *
 550 ldfile_find_command_file (const char *name, const char *extend)
 551 {
 552   search_dirs_type *search;
 553   FILE *result;
 554   char *buffer;
 555   static search_dirs_type *script_search;
 556
 557   /* First try raw name.  */
 558   result = try_open (name, "");
 559   if (result != NULL)
 560     return result;
 561
 562   if (!script_search)
 563     {
 564       char *script_dir = find_scripts_dir ();
 565       if (script_dir)
 566         {
 567           search_dirs_type **save_tail_ptr = search_tail_ptr;
 568           search_tail_ptr = &script_search;
 569           ldfile_add_library_path (script_dir, TRUE);
 570           search_tail_ptr = save_tail_ptr;
 571         }
 572       if (!script_search)
 573         script_search = search_head;
 574       else
 575         script_search->next = search_head;
 576     }
 577
 578   /* Try now prefixes.  */
 579   for (search = script_search; search != NULL; search = search->next)
 580     {
 581
 582       buffer = concat (search->name, slash, name, (const char *) NULL);
 583       result = try_open (buffer, extend);
 584       free (buffer);
 585       if (result)
 586         break;
 587     }
 588
 589   return result;
 590 }
 591
 592 void
 593 ldfile_open_command_file (const char *name)
 594 {
 595   FILE *ldlex_input_stack;
 596   ldlex_input_stack = ldfile_find_command_file (name, "");
 597
 598   if (ldlex_input_stack == NULL)
 599     {
 600       bfd_set_error (bfd_error_system_call);
 601       einfo (_("%P%F: cannot open linker script file %s: %E\n"), name);
 602     }
 603
 604   lex_push_file (ldlex_input_stack, name);
 605
 606   ldfile_input_filename = name;
 607   lineno = 1;
 608
 609   saved_script_handle = ldlex_input_stack;
 610 }
 611
 612 void
 613 ldfile_add_arch (const char *in_name)
 614 {
 615   char *name = xstrdup (in_name);
 616   search_arch_type *new = xmalloc (sizeof (search_arch_type));
 617
 618   ldfile_output_machine_name = in_name;
 619
 620   new->name = name;
 621   new->next = NULL;
 622   while (*name)
 623     {
 624       *name = TOLOWER (*name);
 625       name++;
 626     }
 627   *search_arch_tail_ptr = new;
 628   search_arch_tail_ptr = &new->next;
 629
 630 }
 631
 632 /* Set the output architecture.  */
 633
 634 void
 635 ldfile_set_output_arch (const char *string, enum bfd_architecture defarch)
 636 {
 637   const bfd_arch_info_type *arch = bfd_scan_arch (string);
 638
 639   if (arch)
 640     {
 641       ldfile_output_architecture = arch->arch;
 642       ldfile_output_machine = arch->mach;
 643       ldfile_output_machine_name = arch->printable_name;
 644     }
 645   else if (defarch != bfd_arch_unknown)
 646     ldfile_output_architecture = defarch;
 647   else
 648     einfo (_("%P%F: cannot represent machine `%s'\n"), string);
 649 }