support/xdlfcn.c

   1 /* Support functionality for using dlopen/dlclose/dlsym.
   2    Copyright (C) 2017-2022 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, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <stddef.h>
  20 #include <support/check.h>
  21 #include <support/xdlfcn.h>
  22
  23 void *
  24 xdlopen (const char *filename, int flags)
  25 {
  26   void *dso = dlopen (filename, flags);
  27
  28   if (dso == NULL)
  29     FAIL_EXIT1 ("error: dlopen: %s\n", dlerror ());
  30
  31   return dso;
  32 }
  33
  34 void *
  35 xdlsym (void *handle, const char *symbol)
  36 {
  37   /* Clear any pending errors.  */
  38   dlerror ();
  39
  40   void *sym = dlsym (handle, symbol);
  41
  42   if (sym == NULL)
  43     {
  44       const char *error = dlerror ();
  45       if (error != NULL)
  46         FAIL_EXIT1 ("error: dlsym: %s\n", error);
  47       /* If there was no error, we found a NULL symbol.  Return the
  48          NULL value in this case.  */
  49     }
  50
  51   return sym;
  52 }
  53
  54 void *
  55 xdlvsym (void *handle, const char *symbol, const char *version)
  56 {
  57   /* Clear any pending errors.  */
  58   dlerror ();
  59
  60   void *sym = dlvsym (handle, symbol, version);
  61
  62   if (sym == NULL)
  63     {
  64       const char *error = dlerror ();
  65       if (error != NULL)
  66         FAIL_EXIT1 ("error: dlvsym: %s\n", error);
  67       /* If there was no error, we found a NULL symbol.  Return the
  68          NULL value in this case.  */
  69     }
  70
  71   return sym;
  72 }
  73
  74 void
  75 xdlclose (void *handle)
  76 {
  77   if (dlclose (handle) != 0)
  78     FAIL_EXIT1 ("error: dlclose: %s\n", dlerror ());
  79 }