gmodule/gmodule-os2.c

   1 /* GMODULE - GLIB wrapper code for dynamic module loading
   2  * Copyright (C) 1998, 2000 Tim Janik
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GLib Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 /*
  28  * MT safe
  29  */
  30 #include "config.h"
  31
  32 #include <dlfcn.h>
  33
  34 /* Perl includes <nlist.h> and <link.h> instead of <dlfcn.h> on some systmes? */
  35
  36
  37 /* dlerror() is not implemented on all systems
  38  */
  39 #ifndef G_MODULE_HAVE_DLERROR
  40 /* could we rely on errno's state here? */
  41 #  define dlerror()     "unknown dl-error"
  42 #endif  /* G_MODULE_HAVE_DLERROR */
  43
  44 /* some flags are missing on some systems, so we provide
  45  * harmless defaults.
  46  * The Perl sources say, RTLD_LAZY needs to be defined as (1),
  47  * at least for Solaris 1.
  48  *
  49  * Mandatory:
  50  * RTLD_LAZY   - resolve undefined symbols as code from the dynamic library
  51  *               is executed.
  52  * RTLD_NOW    - resolve all undefined symbols before dlopen returns, and fail
  53  *               if this cannot be done.
  54  * Optionally:
  55  * RTLD_GLOBAL - the external symbols defined in the library will be made
  56  *               available to subsequently loaded libraries.
  57  */
  58 #ifndef RTLD_GLOBAL
  59 #define RTLD_GLOBAL     0
  60 #endif  /* RTLD_GLOBAL */
  61 #ifndef RTLD_LAZY
  62 #define RTLD_LAZY       1
  63 #endif  /* RTLD_LAZY */
  64 #ifndef RTLD_NOW
  65 #define RTLD_NOW        0
  66 #endif  /* RTLD_NOW */
  67
  68
  69 /* --- functions --- */
  70 static gpointer
  71 _g_module_open (const gchar    *file_name,
  72                 gboolean        bind_lazy,
  73                 gboolean        bind_local)
  74 {
  75   gpointer handle;
  76
  77   handle = dlopen (file_name,
  78         (bind_local ? 0 : RTLD_GLOBAL) | (bind_lazy ? RTLD_LAZY : RTLD_NOW));
  79   if (!handle)
  80     g_module_set_error (dlerror ());
  81
  82   return handle;
  83 }
  84
  85 static gpointer
  86 _g_module_self (void)
  87 {
  88   gpointer handle;
  89
  90   /* to query symbols from the program itself, special link options
  91    * are required on some systems.
  92    */
  93
  94   /* XXX, not supported */
  95   handle = NULL;
  96   g_module_set_error ("module handle for self not supported");
  97
  98   return handle;
  99 }
 100
 101 static void
 102 _g_module_close (gpointer handle,
 103                  gboolean is_unref)
 104 {
 105   /* are there any systems out there that have dlopen()/dlclose()
 106    * without a reference count implementation?
 107    */
 108   is_unref |= 1;
 109
 110   if (is_unref)
 111     {
 112       /* XXX, no return code */
 113       dlclose (handle);
 114     }
 115 }
 116
 117 static gpointer
 118 _g_module_symbol (gpointer     handle,
 119                   const gchar *symbol_name)
 120 {
 121   gpointer p;
 122
 123   p = dlsym (handle, symbol_name);
 124   if (!p)
 125     g_module_set_error (dlerror ());
 126
 127   return p;
 128 }
 129
 130 static gchar*
 131 _g_module_build_path (const gchar *directory,
 132                       const gchar *module_name)
 133 {
 134   gchar *suffix = strrchr(module_name, '.');
 135   if (directory && *directory)
 136     if (suffix && (stricmp (suffix, ".dll") == 0))
 137       return g_strconcat (directory, "/", module_name, NULL);
 138     else
 139       return g_strconcat (directory, "/", module_name, ".dll", NULL);
 140   else if (suffix && (stricmp (suffix, ".dll") == 0))
 141     return g_strdup (module_name);
 142   else
 143     return g_strconcat (module_name, ".dll", NULL);
 144 }