dlfcn/dlinfo.c

   1 /* dlinfo -- Get information from the dynamic linker.
   2    Copyright (C) 2003, 2004 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 Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <dlfcn.h>
  21 #include <link.h>
  22 #include <ldsodefs.h>
  23 #include <libintl.h>
  24
  25 #if !defined SHARED && defined IS_IN_libdl
  26
  27 int
  28 dlinfo (void *handle, int request, void *arg)
  29 {
  30   return __dlinfo (handle, request, arg, RETURN_ADDRESS (0));
  31 }
  32
  33 #else
  34
  35 struct dlinfo_args
  36 {
  37   ElfW(Addr) caller;
  38   void *handle;
  39   int request;
  40   void *arg;
  41 };
  42
  43 static void
  44 dlinfo_doit (void *argsblock)
  45 {
  46   struct dlinfo_args *const args = argsblock;
  47   struct link_map *l = args->handle;
  48
  49 # if 0
  50   if (args->handle == RTLD_SELF)
  51     {
  52       Lmid_t nsid;
  53
  54       /* Find the highest-addressed object that CALLER is not below.  */
  55       for (nsid = 0; nsid < DL_NNS; ++nsid)
  56         for (l = GL(dl_ns)[nsid]._ns_loaded; l != NULL; l = l->l_next)
  57           if (caller >= l->l_map_start && caller < l->l_map_end)
  58             /* There must be exactly one DSO for the range of the virtual
  59                memory.  Otherwise something is really broken.  */
  60             break;
  61
  62       if (l == NULL)
  63         GLRO(dl_signal_error) (0, NULL, NULL, N_("\
  64 RTLD_SELF used in code not dynamically loaded"));
  65     }
  66 # endif
  67
  68   switch (args->request)
  69     {
  70     case RTLD_DI_CONFIGADDR:
  71     default:
  72       GLRO(dl_signal_error) (0, NULL, NULL, N_("unsupported dlinfo request"));
  73       break;
  74
  75     case RTLD_DI_LMID:
  76       *(Lmid_t *) args->arg = l->l_ns;
  77       break;
  78
  79     case RTLD_DI_LINKMAP:
  80       *(struct link_map **) args->arg = l;
  81       break;
  82
  83     case RTLD_DI_SERINFO:
  84       _dl_rtld_di_serinfo (l, args->arg, false);
  85       break;
  86     case RTLD_DI_SERINFOSIZE:
  87       _dl_rtld_di_serinfo (l, args->arg, true);
  88       break;
  89
  90     case RTLD_DI_ORIGIN:
  91       strcpy (args->arg, l->l_origin);
  92       break;
  93     }
  94 }
  95
  96 int
  97 __dlinfo (void *handle, int request, void *arg DL_CALLER_DECL)
  98 {
  99 # ifdef SHARED
 100   if (__builtin_expect (_dlfcn_hook != NULL, 0))
 101     return _dlfcn_hook->dlinfo (handle, request, arg,
 102                                 DL_CALLER);
 103 # endif
 104
 105   struct dlinfo_args args = { (ElfW(Addr)) DL_CALLER,
 106                               handle, request, arg };
 107   return _dlerror_run (&dlinfo_doit, &args) ? -1 : 0;
 108 }
 109 # ifdef SHARED
 110 strong_alias (__dlinfo, dlinfo)
 111 # endif
 112 #endif