Imported Upstream version 0.63.0

[hcoop/debian/courier-authlib.git] / libltdl / loaders / dld_link.c

diff --git a/libltdl/loaders/dld_link.c b/libltdl/loaders/dld_link.c
new file mode 100644 (file)
index 0000000..7e882c9
--- /dev/null
+++ b/libltdl/loaders/dld_link.c
@@ -0,0 +1,158 @@
+/* loader-dld_link.c -- dynamic linking with dld
+
+   Copyright (C) 1998, 1999, 2000, 2004, 2006,
+                 2007, 2008 Free Software Foundation, Inc.
+   Written by Thomas Tanner, 1998
+
+   NOTE: The canonical source of this file is maintained with the
+   GNU Libtool package.  Report bugs to bug-libtool@gnu.org.
+
+GNU Libltdl 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.
+
+As a special exception to the GNU Lesser General Public License,
+if you distribute this file as part of a program or library that
+is built using GNU Libtool, you may include this file under the
+same distribution terms that you use for the rest of that program.
+
+GNU Libltdl 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 GNU Libltdl; see the file COPYING.LIB.  If not, a
+copy can be downloaded from  http://www.gnu.org/licenses/lgpl.html,
+or obtained by writing to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
+#include "lt__private.h"
+#include "lt_dlloader.h"
+
+/* Use the preprocessor to rename non-static symbols to avoid namespace
+   collisions when the loader code is statically linked into libltdl.
+   Use the "<module_name>_LTX_" prefix so that the symbol addresses can
+   be fetched from the preloaded symbol list by lt_dlsym():  */
+#define get_vtable     dld_link_LTX_get_vtable
+
+LT_BEGIN_C_DECLS
+LT_SCOPE lt_dlvtable *get_vtable (lt_user_data loader_data);
+LT_END_C_DECLS
+
+
+/* Boilerplate code to set up the vtable for hooking this loader into
+   libltdl's loader list:  */
+static int      vl_exit  (lt_user_data loader_data);
+static lt_module vm_open  (lt_user_data loader_data, const char *filename,
+                           lt_dladvise advise);
+static int      vm_close (lt_user_data loader_data, lt_module module);
+static void *   vm_sym   (lt_user_data loader_data, lt_module module,
+                         const char *symbolname);
+
+static lt_dlvtable *vtable = 0;
+
+/* Return the vtable for this loader, only the name and sym_prefix
+   attributes (plus the virtual function implementations, obviously)
+   change between loaders.  */
+lt_dlvtable *
+get_vtable (lt_user_data loader_data)
+{
+  if (!vtable)
+    {
+      vtable = lt__zalloc (sizeof *vtable);
+    }
+
+  if (vtable && !vtable->name)
+    {
+      vtable->name             = "lt_dld_link";
+      vtable->module_open      = vm_open;
+      vtable->module_close     = vm_close;
+      vtable->find_sym         = vm_sym;
+      vtable->dlloader_exit    = vl_exit;
+      vtable->dlloader_data    = loader_data;
+      vtable->priority         = LT_DLLOADER_APPEND;
+    }
+
+  if (vtable && (vtable->dlloader_data != loader_data))
+    {
+      LT__SETERROR (INIT_LOADER);
+      return 0;
+    }
+
+  return vtable;
+}
+
+
+
+/* --- IMPLEMENTATION --- */
+
+
+#if defined(HAVE_DLD_H)
+#  include <dld.h>
+#endif
+
+/* A function called through the vtable when this loader is no
+   longer needed by the application.  */
+static int
+vl_exit (lt_user_data LT__UNUSED loader_data)
+{
+  vtable = NULL;
+  return 0;
+}
+
+/* A function called through the vtable to open a module with this
+   loader.  Returns an opaque representation of the newly opened
+   module for processing with this loader's other vtable functions.  */
+static lt_module
+vm_open (lt_user_data LT__UNUSED loader_data, const char *filename,
+         lt_dladvise LT__UNUSED advise)
+{
+  lt_module module = lt__strdup (filename);
+
+  if (dld_link (filename) != 0)
+    {
+      LT__SETERROR (CANNOT_OPEN);
+      FREE (module);
+    }
+
+  return module;
+}
+
+/* A function called through the vtable when a particular module
+   should be unloaded.  */
+static int
+vm_close (lt_user_data LT__UNUSED loader_data, lt_module module)
+{
+  int errors = 0;
+
+  if (dld_unlink_by_file ((char*)(module), 1) != 0)
+    {
+      LT__SETERROR (CANNOT_CLOSE);
+      ++errors;
+    }
+  else
+    {
+      FREE (module);
+    }
+
+  return errors;
+}
+
+/* A function called through the vtable to get the address of
+   a symbol loaded from a particular module.  */
+static void *
+vm_sym (lt_user_data LT__UNUSED loader_data, lt_module LT__UNUSED module,
+       const char *name)
+{
+  void *address = dld_get_func (name);
+
+  if (!address)
+    {
+      LT__SETERROR (SYMBOL_NOT_FOUND);
+    }
+
+  return address;
+}