mutter/deps/gmodule/gmodule-dld.c

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/* 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.
*/
/*
* Modified by the GLib Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GLib Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GLib at ftp://ftp.gtk.org/pub/gtk/.
*/
/*
* MT safe
*/
#include "config.h"
#include <dl.h>
/* some flags are missing on some systems, so we provide
* harmless defaults.
*
* Mandatory:
* BIND_IMMEDIATE - Resolve symbol references when the library is loaded.
* BIND_DEFERRED - Delay code symbol resolution until actual reference.
*
* Optionally:
* BIND_FIRST - Place the library at the head of the symbol search order.
* BIND_NONFATAL - The default BIND_IMMEDIATE behavior is to treat all unsatisfied
* symbols as fatal. This flag allows binding of unsatisfied code
* symbols to be deferred until use.
* [Perl: For certain libraries, like DCE, deferred binding often
* causes run time problems. Adding BIND_NONFATAL to BIND_IMMEDIATE
* still allows unresolved references in situations like this.]
* BIND_NOSTART - Do not call the initializer for the shared library when the
* library is loaded, nor on a future call to shl_unload().
* BIND_VERBOSE - Print verbose messages concerning possible unsatisfied symbols.
*
* hp9000s700/hp9000s800:
* BIND_RESTRICTED - Restrict symbols visible by the library to those present at
* library load time.
* DYNAMIC_PATH - Allow the loader to dynamically search for the library specified
* by the path argument.
*/
#ifndef DYNAMIC_PATH
#define DYNAMIC_PATH 0
#endif /* DYNAMIC_PATH */
#ifndef BIND_RESTRICTED
#define BIND_RESTRICTED 0
#endif /* BIND_RESTRICTED */
#define OPT_BIND_FLAGS (BIND_NONFATAL | BIND_VERBOSE)
/* --- functions --- */
/*
* shl_load() does not appear to support making symbols invisible to
* the global namespace. However, the default is to put the library
* last in the search order, which is approximately what we want,
* since it will cause symbols that conflict with existing symbols to
* be invisible. It is unclear if BIND_FIRST should be used when
* bind_local==0, since it may cause the loaded symbols to be used
* preferentially to the application's symbols, which is Almost
* Always Wrong. --ds
*/
static gpointer
_g_module_open (const gchar *file_name,
gboolean bind_lazy,
gboolean bind_local)
{
shl_t shl_handle;
shl_handle = shl_load (file_name,
(bind_lazy ? BIND_DEFERRED : BIND_IMMEDIATE) | OPT_BIND_FLAGS, 0);
if (!shl_handle)
{
/* the hp-docs say we should better abort() if errno==ENOSYM ;( */
g_module_set_error (g_strerror (errno));
}
return (gpointer) shl_handle;
}
static gpointer
_g_module_self (void)
{
shl_t shl_handle;
shl_handle = PROG_HANDLE;
if (!shl_handle)
g_module_set_error (g_strerror (errno));
return shl_handle;
}
static void
_g_module_close (gpointer handle,
gboolean is_unref)
{
if (!is_unref)
{
if (shl_unload ((shl_t) handle) != 0)
g_module_set_error (g_strerror (errno));
}
}
static gpointer
_g_module_symbol (gpointer handle,
const gchar *symbol_name)
{
gpointer p = NULL;
/* should we restrict lookups to TYPE_PROCEDURE?
*/
if (handle == PROG_HANDLE)
{
/* PROG_HANDLE will only lookup symbols in the program itself, not honouring
* libraries. passing NULL as a handle will also try to lookup the symbol
* in currently loaded libraries. fix pointed out and supplied by:
* David Gero <dgero@nortelnetworks.com>
*/
handle = NULL;
}
if (shl_findsym ((shl_t*) &handle, symbol_name, TYPE_UNDEFINED, &p) != 0 ||
handle == NULL || p == NULL)
{
/* the hp-docs say we should better abort() if errno==ENOSYM ;( */
g_module_set_error (g_strerror (errno));
}
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, ".sl", NULL);
else if (strncmp (module_name, "lib", 3) == 0)
return g_strdup (module_name);
else
return g_strconcat ("lib", module_name, ".sl", NULL);
}