/* GMODULE - GLIB wrapper code for dynamic module loading

 * Copyright (C) 1998, 2000 Tim Janik

 *

 * dyld (Darwin) GMODULE implementation

 * Copyright (C) 2001 Dan Winship

 *

 * 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 2.1 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, see <http://www.gnu.org/licenses/>.

 */

#include "config.h"

#include <mach-o/dyld.h>

static gpointer self_module = GINT_TO_POINTER (1);

static gpointer

_g_module_open (const gchar *file_name,

		gboolean     bind_lazy,

		gboolean     bind_local)

{

  NSObjectFileImage image;

  NSObjectFileImageReturnCode ret;

  NSModule module;

  unsigned long options;

  char *msg;

  ret = NSCreateObjectFileImageFromFile (file_name, &image);

  if (ret != NSObjectFileImageSuccess)

    {

      switch (ret)

	{

	case NSObjectFileImageInappropriateFile:

	case NSObjectFileImageFormat:

	  msg = g_strdup_printf ("%s is not a loadable module", file_name);

	  break;

	case NSObjectFileImageArch:

	  msg = g_strdup_printf ("%s is not built for this architecture",

				 file_name);

	  break;

	case NSObjectFileImageAccess:

	  if (access (file_name, F_OK) == 0)

	    msg = g_strdup_printf ("%s: permission denied", file_name);

	  else

	    msg = g_strdup_printf ("%s: no such file or directory", file_name);

	  break;

	default:

	  msg = g_strdup_printf ("unknown error for %s", file_name);

	  break;

	}

      g_module_set_error (msg);

      g_free (msg);

      return NULL;

    }

  options = NSLINKMODULE_OPTION_RETURN_ON_ERROR;

  if (bind_local)

    options |= NSLINKMODULE_OPTION_PRIVATE;

  if (!bind_lazy)

    options |= NSLINKMODULE_OPTION_BINDNOW;

  module = NSLinkModule (image, file_name, options);

  NSDestroyObjectFileImage (image);

  if (!module)

    {

      NSLinkEditErrors c;

      int error_number;

      const char *file, *error;

      NSLinkEditError (&c, &error_number, &file, &error);

      msg = g_strdup_printf ("could not link %s: %s", file_name, error);

      g_module_set_error (msg);

      g_free (msg);

      return NULL;

    }

  return module;

}

static gpointer

_g_module_self (void)

{

  return &self_module;

}

static void

_g_module_close (gpointer handle,

		 gboolean is_unref)

{

  if (handle == &self_module)

    return;

  if (!NSUnLinkModule (handle, 0))

    g_module_set_error ("could not unlink module");

}

static gpointer

_g_module_symbol (gpointer     handle,

		  const gchar *symbol_name)

{

  NSSymbol sym;

  char *msg;

  if (handle == &self_module)

    {

      if (NSIsSymbolNameDefined (symbol_name))

	sym = NSLookupAndBindSymbol (symbol_name);

      else

	sym = NULL;

    }

  else

    sym = NSLookupSymbolInModule (handle, symbol_name);

  if (!sym)

    {

      msg = g_strdup_printf ("no such symbol %s", symbol_name);

      g_module_set_error (msg);

      g_free (msg);

      return NULL;

    }

  return NSAddressOfSymbol (sym);

}

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);

}