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
_g_module_open(const gchar * file_name,gboolean bind_lazy,gboolean bind_local)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
_g_module_self(void)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
_g_module_close(gpointer handle,gboolean is_unref)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
_g_module_symbol(gpointer handle,const gchar * symbol_name)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*
_g_module_build_path(const gchar * directory,const gchar * module_name)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 }
145