text: /* GMODULE - GLIB wrapper code for dynamic module loading
   * Copyright (C) 1998, 2000 Tim Janik
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the
   * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   * Boston, MA 02111-1307, USA.
   */
  
  /* 
   * MT safe
   */
  
  /* because we are compatible with archive format only since AIX 4.3 */
  
  #define __AR_BIG__
  #include <ar.h>
  #include <stdlib.h>
  
  #include <dlfcn.h>
  
  /* --- functions --- */
  static gchar*
  fetch_dlerror (gboolean replace_null)
  {
    gchar *msg = dlerror ();
  
    /* make sure we always return an error message != NULL, if
     * expected to do so. */
  
    if (!msg && replace_null)
      return "unknown dl-error";
  
    return msg;
  }
  
  static gchar* _g_module_get_member(const gchar* file_name)
  {
    gchar* member = NULL;
    struct fl_hdr file_header;
    struct ar_hdr ar_header;
    long first_member;
    long name_len;
    int fd;
  
    fd = open(file_name, O_RDONLY);
    if (fd == -1)
      return NULL;
  
    if (read(fd, (void*)&file_header, FL_HSZ) != FL_HSZ)
      goto exit;
  
    if (strncmp(file_header.fl_magic, AIAMAGBIG, SAIAMAG) != 0)
      goto exit;
  
    /* read first archive file member header */
  
    first_member = atol(file_header.fl_fstmoff);
  
    if (lseek(fd, first_member, SEEK_SET) != first_member)
      goto exit;
  
    if (read(fd, (void*)&ar_header, AR_HSZ - 2) != AR_HSZ - 2)
      goto exit;
  
    /* read member name */
  
    name_len = atol(ar_header.ar_namlen);
  
    member = g_malloc(name_len+1);
    if (!member)
      goto exit;
  
    if (read(fd, (void*)member, name_len) != name_len)
      {
        g_free(member);
        member = NULL;
        goto exit;
      }
  
    member[name_len] = 0;
  
  exit:
    close(fd);
  
    return member;
  }
  
  static gpointer
  _g_module_open (const gchar *file_name,
  		gboolean     bind_lazy,
  		gboolean     bind_local)
  {
    gpointer handle;
    gchar* member;
    gchar* full_name;
  
    /* extract name of first member of archive */
  
    member = _g_module_get_member (file_name);
    if (member != NULL)
      {
        full_name = g_strconcat (file_name, "(", member, ")", NULL);
        g_free (member);
      }
    else
      full_name = g_strdup (file_name);
    
    handle = dlopen (full_name, 
  		   (bind_local ? RTLD_LOCAL : RTLD_GLOBAL) | RTLD_MEMBER | (bind_lazy ? RTLD_LAZY : RTLD_NOW));
  
    g_free (full_name);
  
    if (!handle)
      g_module_set_error (fetch_dlerror (TRUE));
    
    return handle;
  }
  
  static gpointer
  _g_module_self (void)
  {
    gpointer handle;
  
    handle = dlopen (NULL, RTLD_GLOBAL | RTLD_LAZY);
    if (!handle)
      g_module_set_error (fetch_dlerror (TRUE));
    
    return handle;
  }
  
  static void
  _g_module_close (gpointer handle,
  		 gboolean is_unref)
  {
    /* are there any systems out there that have dlopen()/dlclose()
     * without a reference count implementation?
     */
    is_unref |= 1;
    
    if (is_unref)
      {
        if (dlclose (handle) != 0)
  	g_module_set_error (fetch_dlerror (TRUE));
      }
  }
  
  static gpointer
  _g_module_symbol (gpointer     handle,
  		  const gchar *symbol_name)
  {
    gpointer p;
    
    p = dlsym (handle, symbol_name);
    if (!p)
      g_module_set_error (fetch_dlerror (FALSE));
    
    return p;
  }
  
  static gchar*
  _g_module_build_path (const gchar *directory,
  		      const gchar *module_name)
  {
    if (directory && *directory) {
      if (strncmp (module_name, "lib", 3) == 0)
        return g_strconcat (directory, "/", module_name, NULL);
      else
        return g_strconcat (directory, "/lib", module_name, "." G_MODULE_SUFFIX, NULL);
    } else if (strncmp (module_name, "lib", 3) == 0)
      return g_strdup (module_name);
    else
      return g_strconcat ("lib", module_name, "." G_MODULE_SUFFIX, NULL);
  }
  