elf/dl-support.c

   1 /* Support for dynamic linking code in static libc.
   2    Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 /* This file defines some things that for the dynamic linker are defined in
  21    rtld.c and dl-sysdep.c in ways appropriate to bootstrap dynamic linking.  */
  22
  23 #include <errno.h>
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <elf/ldsodefs.h>
  27 #include <dl-machine.h>
  28
  29 extern char *__progname;
  30 char **_dl_argv = &__progname;  /* This is checked for some error messages.  */
  31
  32 /* This defines the default search path for libraries.
  33    For the dynamic linker it is set by -rpath when linking.  */
  34 const char *_dl_rpath = DEFAULT_RPATH;
  35
  36 /* Name of the architecture.  */
  37 const char *_dl_platform;
  38 size_t _dl_platformlen;
  39
  40 int _dl_debug_libs;
  41 int _dl_debug_impcalls;
  42 int _dl_debug_bindings;
  43 int _dl_debug_symbols;
  44 int _dl_debug_versions;
  45 int _dl_debug_reloc;
  46 int _dl_debug_files;
  47
  48 /* If nonzero print warnings about problematic situations.  */
  49 int _dl_verbose;
  50
  51 /* Structure to store information about search paths.  */
  52 struct r_search_path *_dl_search_paths;
  53
  54 /* We never do profiling.  */
  55 const char *_dl_profile;
  56
  57 /* Names of shared object for which the RPATHs should be ignored.  */
  58 const char *_dl_inhibit_rpath;
  59
  60 /* The map for the object we will profile.  */
  61 struct link_map *_dl_profile_map;
  62
  63 /* This is the address of the last stack address ever used.  */
  64 void *__libc_stack_end;
  65
  66 /* Path where the binary is found.  */
  67 const char *_dl_origin_path;
  68
  69 /* Initially empty list of loaded objects.  */
  70 struct link_map *_dl_loaded;
  71
  72 /* Fake scope.  In dynamically linked binaries this is the scope of the
  73    main application but here we don't have  something like this.  So
  74    create a fake scope containing nothing.  */
  75 static struct r_scope_elem fake_scope;
  76 /* Variable which can be used in lookup to process the global scope.  */
  77 struct r_scope_elem *_dl_global_scope[2] = { &fake_scope, NULL };
  78 /* This is a global pointer to this structure which is public.  It is
  79    used by dlopen/dlclose to add and remove objects from what is regarded
  80    to be the global scope.  */
  81 struct r_scope_elem *_dl_main_searchlist = &fake_scope;
  82
  83
  84 static void non_dynamic_init (void) __attribute__ ((unused));
  85
  86 static void
  87 non_dynamic_init (void)
  88 {
  89   _dl_verbose = *(getenv ("LD_WARN") ?: "") == '\0' ? 0 : 1;
  90
  91   _dl_pagesize = __getpagesize ();
  92
  93   /* Initialize the data structures for the search paths for shared
  94      objects.  */
  95   _dl_init_paths (getenv ("LD_LIBRARY_PATH"));
  96
  97 #ifdef DL_PLATFORM_INIT
  98   DL_PLATFORM_INIT;
  99 #endif
 100
 101   /* Now determine the length of the platform string.  */
 102   if (_dl_platform != NULL)
 103     _dl_platformlen = strlen (_dl_platform);
 104 }
 105 text_set_element (__libc_subinit, non_dynamic_init);
 106
 107 const struct r_strlenpair *
 108 internal_function
 109 _dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz,
 110                       size_t *max_capstrlen)
 111 {
 112   struct r_strlenpair *result;
 113
 114   /* XXX We don't try to find the capabilities in this case.  */
 115   result = (struct r_strlenpair *) malloc (sizeof (*result));
 116   if (result == NULL)
 117     _dl_signal_error (ENOMEM, NULL, "cannot create capability list");
 118
 119   result[0].str = (char *) result;      /* Does not really matter.  */
 120   result[0].len = 0;
 121
 122   *sz = 1;
 123   return result;
 124 }