Coverage Report

Created: 2018-09-25 13:52

/src/glib/gmodule/gmodule.c
Line
Count
Source (jump to first uncovered line)
1
/* GMODULE - GLIB wrapper code for dynamic module loading
2
 * Copyright (C) 1998 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 2.1 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, see <http://www.gnu.org/licenses/>.
16
 */
17
18
/*
19
 * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
20
 * file for a list of people on the GLib Team.  See the ChangeLog
21
 * files for a list of changes.  These files are distributed with
22
 * GLib at ftp://ftp.gtk.org/pub/gtk/. 
23
 */
24
25
/* 
26
 * MT safe
27
 */
28
29
#include "config.h"
30
31
#include "glib.h"
32
#include "gmodule.h"
33
34
#include <errno.h>
35
#include <string.h>
36
#include <sys/types.h>
37
#include <sys/stat.h>
38
#include <fcntl.h>
39
#ifdef G_OS_UNIX
40
#include <unistd.h>
41
#endif
42
#ifdef G_OS_WIN32
43
#include <io.h>   /* For open() and close() prototypes. */
44
#endif
45
46
#include "gmoduleconf.h"
47
#include "gstdio.h"
48
49
/**
50
 * SECTION:modules
51
 * @title: Dynamic Loading of Modules
52
 * @short_description: portable method for dynamically loading 'plug-ins'
53
 *
54
 * These functions provide a portable way to dynamically load object files
55
 * (commonly known as 'plug-ins'). The current implementation supports all
56
 * systems that provide an implementation of dlopen() (e.g. Linux/Sun), as
57
 * well as Windows platforms via DLLs.
58
 *
59
 * A program which wants to use these functions must be linked to the
60
 * libraries output by the command `pkg-config --libs gmodule-2.0`.
61
 *
62
 * To use them you must first determine whether dynamic loading
63
 * is supported on the platform by calling g_module_supported().
64
 * If it is, you can open a module with g_module_open(),
65
 * find the module's symbols (e.g. function names) with g_module_symbol(),
66
 * and later close the module with g_module_close().
67
 * g_module_name() will return the file name of a currently opened module.
68
 *
69
 * If any of the above functions fail, the error status can be found with
70
 * g_module_error().
71
 *
72
 * The #GModule implementation features reference counting for opened modules,
73
 * and supports hook functions within a module which are called when the
74
 * module is loaded and unloaded (see #GModuleCheckInit and #GModuleUnload).
75
 *
76
 * If your module introduces static data to common subsystems in the running
77
 * program, e.g. through calling
78
 * `g_quark_from_static_string ("my-module-stuff")`,
79
 * it must ensure that it is never unloaded, by calling g_module_make_resident().
80
 *
81
 * Example: Calling a function defined in a GModule
82
 * |[<!-- language="C" --> 
83
 * // the function signature for 'say_hello'
84
 * typedef void (* SayHelloFunc) (const char *message);
85
 *
86
 * gboolean
87
 * just_say_hello (const char *filename, GError **error)
88
 * {
89
 *   SayHelloFunc  say_hello;
90
 *   GModule      *module;
91
 *
92
 *   module = g_module_open (filename, G_MODULE_BIND_LAZY);
93
 *   if (!module)
94
 *     {
95
 *       g_set_error (error, FOO_ERROR, FOO_ERROR_BLAH,
96
 *                    "%s", g_module_error ());
97
 *       return FALSE;
98
 *     }
99
 *
100
 *   if (!g_module_symbol (module, "say_hello", (gpointer *)&say_hello))
101
 *     {
102
 *       g_set_error (error, SAY_ERROR, SAY_ERROR_OPEN,
103
 *                    "%s: %s", filename, g_module_error ());
104
 *       if (!g_module_close (module))
105
 *         g_warning ("%s: %s", filename, g_module_error ());
106
 *       return FALSE;
107
 *     }
108
 *
109
 *   if (say_hello == NULL)
110
 *     {
111
 *       g_set_error (error, SAY_ERROR, SAY_ERROR_OPEN,
112
 *                    "symbol say_hello is NULL");
113
 *       if (!g_module_close (module))
114
 *         g_warning ("%s: %s", filename, g_module_error ());
115
 *       return FALSE;
116
 *     }
117
 *
118
 *   // call our function in the module
119
 *   say_hello ("Hello world!");
120
 *
121
 *   if (!g_module_close (module))
122
 *     g_warning ("%s: %s", filename, g_module_error ());
123
 *   return TRUE;
124
 *  }
125
 * ]|
126
 */
127
128
/**
129
 * GModule:
130
 *
131
 * The #GModule struct is an opaque data structure to represent a
132
 * [dynamically-loaded module][glib-Dynamic-Loading-of-Modules].
133
 * It should only be accessed via the following functions.
134
 */
135
136
/**
137
 * GModuleCheckInit:
138
 * @module: the #GModule corresponding to the module which has just been loaded
139
 *
140
 * Specifies the type of the module initialization function.
141
 * If a module contains a function named g_module_check_init() it is called
142
 * automatically when the module is loaded. It is passed the #GModule structure
143
 * and should return %NULL on success or a string describing the initialization
144
 * error.
145
 *
146
 * Returns: %NULL on success, or a string describing the initialization error
147
 */
148
149
/**
150
 * GModuleUnload:
151
 * @module: the #GModule about to be unloaded
152
 *
153
 * Specifies the type of the module function called when it is unloaded.
154
 * If a module contains a function named g_module_unload() it is called
155
 * automatically when the module is unloaded.
156
 * It is passed the #GModule structure.
157
 */
158
159
/**
160
 * G_MODULE_SUFFIX:
161
 *
162
 * Expands to the proper shared library suffix for the current platform
163
 * without the leading dot. For most Unices and Linux this is "so", and
164
 * for Windows this is "dll".
165
 */
166
167
/**
168
 * G_MODULE_EXPORT:
169
 *
170
 * Used to declare functions exported by libraries or modules.
171
 *
172
 * When compiling for Windows, it marks the symbol as `dllexport`.
173
 *
174
 * When compiling for Linux and Unices, it marks the symbol as having `default`
175
 * visibility. This is no-op unless the code is being compiled with a
176
 * non-default
177
 * [visibility flag](https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#index-fvisibility-1260)
178
 * such as `hidden`.
179
 */
180
181
/**
182
 * G_MODULE_IMPORT:
183
 *
184
 * Used to declare functions imported from modules.
185
 */
186
187
/* We maintain a list of modules, so we can reference count them.
188
 * That's needed because some platforms don't support references counts on
189
 * modules. Also, the module for the program itself is kept seperately for
190
 * faster access and because it has special semantics.
191
 */
192
193
194
/* --- structures --- */
195
struct _GModule
196
{
197
  gchar *file_name;
198
  gpointer handle;
199
  guint ref_count : 31;
200
  guint is_resident : 1;
201
  GModuleUnload unload;
202
  GModule *next;
203
};
204
205
206
/* --- prototypes --- */
207
static gpointer   _g_module_open    (const gchar  *file_name,
208
             gboolean  bind_lazy,
209
             gboolean  bind_local);
210
static void   _g_module_close   (gpointer  handle,
211
             gboolean  is_unref);
212
static gpointer   _g_module_self    (void);
213
static gpointer   _g_module_symbol  (gpointer  handle,
214
             const gchar  *symbol_name);
215
static gchar*   _g_module_build_path  (const gchar  *directory,
216
             const gchar  *module_name);
217
static inline void  g_module_set_error  (const gchar  *error);
218
static inline GModule*  g_module_find_by_handle (gpointer  handle);
219
static inline GModule*  g_module_find_by_name (const gchar  *name);
220
221
222
/* --- variables --- */
223
static GModule       *modules = NULL;
224
static GModule       *main_module = NULL;
225
static GPrivate       module_error_private = G_PRIVATE_INIT (g_free);
226
static gboolean       module_debug_initialized = FALSE;
227
static guint        module_debug_flags = 0;
228
229
230
/* --- inline functions --- */
231
static inline GModule*
232
g_module_find_by_handle (gpointer handle)
233
0
{
234
0
  GModule *module;
235
0
  GModule *retval = NULL;
236
0
  
237
0
  if (main_module && main_module->handle == handle)
238
0
    retval = main_module;
239
0
  else
240
0
    for (module = modules; module; module = module->next)
241
0
      if (handle == module->handle)
242
0
  {
243
0
    retval = module;
244
0
    break;
245
0
  }
246
0
247
0
  return retval;
248
0
}
249
250
static inline GModule*
251
g_module_find_by_name (const gchar *name)
252
0
{
253
0
  GModule *module;
254
0
  GModule *retval = NULL;
255
0
  
256
0
  for (module = modules; module; module = module->next)
257
0
    if (strcmp (name, module->file_name) == 0)
258
0
  {
259
0
    retval = module;
260
0
    break;
261
0
  }
262
0
263
0
  return retval;
264
0
}
265
266
static inline void
267
g_module_set_error_unduped (gchar *error)
268
0
{
269
0
  g_private_replace (&module_error_private, error);
270
0
  errno = 0;
271
0
}
272
273
static inline void
274
g_module_set_error (const gchar *error)
275
0
{
276
0
  g_module_set_error_unduped (g_strdup (error));
277
0
}
278
279
280
/* --- include platform specifc code --- */
281
0
#define SUPPORT_OR_RETURN(rv) { g_module_set_error (NULL); }
282
#if (G_MODULE_IMPL == G_MODULE_IMPL_DL)
283
#include "gmodule-dl.c"
284
#elif (G_MODULE_IMPL == G_MODULE_IMPL_WIN32)
285
#include "gmodule-win32.c"
286
#elif (G_MODULE_IMPL == G_MODULE_IMPL_DYLD)
287
#include "gmodule-dyld.c"
288
#elif (G_MODULE_IMPL == G_MODULE_IMPL_AR)
289
#include "gmodule-ar.c"
290
#else
291
#undef  SUPPORT_OR_RETURN
292
#define SUPPORT_OR_RETURN(rv) { g_module_set_error ("dynamic modules are " \
293
                                              "not supported by this system"); return rv; }
294
static gpointer
295
_g_module_open (const gchar *file_name,
296
    gboolean   bind_lazy,
297
    gboolean   bind_local)
298
{
299
  return NULL;
300
}
301
static void
302
_g_module_close (gpointer  handle,
303
     gboolean  is_unref)
304
{
305
}
306
static gpointer
307
_g_module_self (void)
308
{
309
  return NULL;
310
}
311
static gpointer
312
_g_module_symbol (gpointer   handle,
313
      const gchar *symbol_name)
314
{
315
  return NULL;
316
}
317
static gchar*
318
_g_module_build_path (const gchar *directory,
319
          const gchar *module_name)
320
{
321
  return NULL;
322
}
323
#endif  /* no implementation */
324
325
/* --- functions --- */
326
327
/**
328
 * g_module_supported:
329
 *
330
 * Checks if modules are supported on the current platform.
331
 *
332
 * Returns: %TRUE if modules are supported
333
 */
334
gboolean
335
g_module_supported (void)
336
0
{
337
0
  SUPPORT_OR_RETURN (FALSE);
338
0
  
339
0
  return TRUE;
340
0
}
341
342
static gchar*
343
parse_libtool_archive (const gchar* libtool_name)
344
0
{
345
0
  const guint TOKEN_DLNAME = G_TOKEN_LAST + 1;
346
0
  const guint TOKEN_INSTALLED = G_TOKEN_LAST + 2;
347
0
  const guint TOKEN_LIBDIR = G_TOKEN_LAST + 3;
348
0
  gchar *lt_dlname = NULL;
349
0
  gboolean lt_installed = TRUE;
350
0
  gchar *lt_libdir = NULL;
351
0
  gchar *name;
352
0
  GTokenType token;
353
0
  GScanner *scanner;
354
0
  
355
0
  int fd = g_open (libtool_name, O_RDONLY, 0);
356
0
  if (fd < 0)
357
0
    {
358
0
      gchar *display_libtool_name = g_filename_display_name (libtool_name);
359
0
      g_module_set_error_unduped (g_strdup_printf ("failed to open libtool archive \"%s\"", display_libtool_name));
360
0
      g_free (display_libtool_name);
361
0
      return NULL;
362
0
    }
363
0
  /* search libtool's dlname specification  */
364
0
  scanner = g_scanner_new (NULL);
365
0
  g_scanner_input_file (scanner, fd);
366
0
  scanner->config->symbol_2_token = TRUE;
367
0
  g_scanner_scope_add_symbol (scanner, 0, "dlname", 
368
0
            GUINT_TO_POINTER (TOKEN_DLNAME));
369
0
  g_scanner_scope_add_symbol (scanner, 0, "installed", 
370
0
            GUINT_TO_POINTER (TOKEN_INSTALLED));
371
0
  g_scanner_scope_add_symbol (scanner, 0, "libdir", 
372
0
            GUINT_TO_POINTER (TOKEN_LIBDIR));
373
0
  while (!g_scanner_eof (scanner))
374
0
    {
375
0
      token = g_scanner_get_next_token (scanner);
376
0
      if (token == TOKEN_DLNAME || token == TOKEN_INSTALLED || 
377
0
    token == TOKEN_LIBDIR)
378
0
  {
379
0
    if (g_scanner_get_next_token (scanner) != '=' ||
380
0
        g_scanner_get_next_token (scanner) != 
381
0
        (token == TOKEN_INSTALLED ? 
382
0
         G_TOKEN_IDENTIFIER : G_TOKEN_STRING))
383
0
      {
384
0
        gchar *display_libtool_name = g_filename_display_name (libtool_name);
385
0
        g_module_set_error_unduped (g_strdup_printf ("unable to parse libtool archive \"%s\"", display_libtool_name));
386
0
        g_free (display_libtool_name);
387
0
388
0
        g_free (lt_dlname);
389
0
        g_free (lt_libdir);
390
0
        g_scanner_destroy (scanner);
391
0
        close (fd);
392
0
393
0
        return NULL;
394
0
      }
395
0
    else
396
0
      {
397
0
        if (token == TOKEN_DLNAME)
398
0
    {
399
0
      g_free (lt_dlname);
400
0
      lt_dlname = g_strdup (scanner->value.v_string);
401
0
    }
402
0
        else if (token == TOKEN_INSTALLED)
403
0
    lt_installed = 
404
0
      strcmp (scanner->value.v_identifier, "yes") == 0;
405
0
        else /* token == TOKEN_LIBDIR */
406
0
    {
407
0
      g_free (lt_libdir);
408
0
      lt_libdir = g_strdup (scanner->value.v_string);
409
0
    }
410
0
      }
411
0
  }      
412
0
    }
413
0
414
0
  if (!lt_installed)
415
0
    {
416
0
      gchar *dir = g_path_get_dirname (libtool_name);
417
0
      g_free (lt_libdir);
418
0
      lt_libdir = g_strconcat (dir, G_DIR_SEPARATOR_S ".libs", NULL);
419
0
      g_free (dir);
420
0
    }
421
0
422
0
  name = g_strconcat (lt_libdir, G_DIR_SEPARATOR_S, lt_dlname, NULL);
423
0
  
424
0
  g_free (lt_dlname);
425
0
  g_free (lt_libdir);
426
0
  g_scanner_destroy (scanner);
427
0
  close (fd);
428
0
429
0
  return name;
430
0
}
431
432
static inline gboolean
433
str_check_suffix (const gchar* string,
434
      const gchar* suffix)
435
0
{
436
0
  gsize string_len = strlen (string);    
437
0
  gsize suffix_len = strlen (suffix);    
438
0
439
0
  return string_len >= suffix_len && 
440
0
    strcmp (string + string_len - suffix_len, suffix) == 0;
441
0
}
442
443
enum
444
{
445
  G_MODULE_DEBUG_RESIDENT_MODULES = 1 << 0,
446
  G_MODULE_DEBUG_BIND_NOW_MODULES = 1 << 1
447
};
448
449
static void
450
_g_module_debug_init (void)
451
0
{
452
0
  const GDebugKey keys[] = {
453
0
    { "resident-modules", G_MODULE_DEBUG_RESIDENT_MODULES },
454
0
    { "bind-now-modules", G_MODULE_DEBUG_BIND_NOW_MODULES }
455
0
  };
456
0
  const gchar *env;
457
0
458
0
  env = g_getenv ("G_DEBUG");
459
0
460
0
  module_debug_flags =
461
0
    !env ? 0 : g_parse_debug_string (env, keys, G_N_ELEMENTS (keys));
462
0
463
0
  module_debug_initialized = TRUE;
464
0
}
465
466
static GRecMutex g_module_global_lock;
467
468
/**
469
 * g_module_open:
470
 * @file_name: (nullable): the name of the file containing the module, or %NULL
471
 *     to obtain a #GModule representing the main program itself
472
 * @flags: the flags used for opening the module. This can be the
473
 *     logical OR of any of the #GModuleFlags
474
 *
475
 * Opens a module. If the module has already been opened,
476
 * its reference count is incremented.
477
 *
478
 * First of all g_module_open() tries to open @file_name as a module.
479
 * If that fails and @file_name has the ".la"-suffix (and is a libtool
480
 * archive) it tries to open the corresponding module. If that fails
481
 * and it doesn't have the proper module suffix for the platform
482
 * (#G_MODULE_SUFFIX), this suffix will be appended and the corresponding
483
 * module will be opended. If that fails and @file_name doesn't have the
484
 * ".la"-suffix, this suffix is appended and g_module_open() tries to open
485
 * the corresponding module. If eventually that fails as well, %NULL is
486
 * returned.
487
 *
488
 * Returns: a #GModule on success, or %NULL on failure
489
 */
490
GModule*
491
g_module_open (const gchar    *file_name,
492
         GModuleFlags    flags)
493
0
{
494
0
  GModule *module;
495
0
  gpointer handle = NULL;
496
0
  gchar *name = NULL;
497
0
  
498
0
  SUPPORT_OR_RETURN (NULL);
499
0
  
500
0
  g_rec_mutex_lock (&g_module_global_lock);
501
0
502
0
  if (G_UNLIKELY (!module_debug_initialized))
503
0
    _g_module_debug_init ();
504
0
505
0
  if (module_debug_flags & G_MODULE_DEBUG_BIND_NOW_MODULES)
506
0
    flags &= ~G_MODULE_BIND_LAZY;
507
0
508
0
  if (!file_name)
509
0
    {      
510
0
      if (!main_module)
511
0
  {
512
0
    handle = _g_module_self ();
513
0
/* On Android 64 bit, RTLD_DEFAULT is (void *)0x0
514
0
 * so it always fails to create main_module if file_name is NULL */
515
0
#if !defined(__BIONIC__) || !defined(__LP64__)
516
0
    if (handle)
517
0
#endif
518
0
      {
519
0
        main_module = g_new (GModule, 1);
520
0
        main_module->file_name = NULL;
521
0
        main_module->handle = handle;
522
0
        main_module->ref_count = 1;
523
0
        main_module->is_resident = TRUE;
524
0
        main_module->unload = NULL;
525
0
        main_module->next = NULL;
526
0
      }
527
0
  }
528
0
      else
529
0
  main_module->ref_count++;
530
0
531
0
      g_rec_mutex_unlock (&g_module_global_lock);
532
0
      return main_module;
533
0
    }
534
0
  
535
0
  /* we first search the module list by name */
536
0
  module = g_module_find_by_name (file_name);
537
0
  if (module)
538
0
    {
539
0
      module->ref_count++;
540
0
      
541
0
      g_rec_mutex_unlock (&g_module_global_lock);
542
0
      return module;
543
0
    }
544
0
545
0
  /* check whether we have a readable file right away */
546
0
  if (g_file_test (file_name, G_FILE_TEST_IS_REGULAR))
547
0
    name = g_strdup (file_name);
548
0
  /* try completing file name with standard library suffix */
549
0
  if (!name)
550
0
    {
551
0
      name = g_strconcat (file_name, "." G_MODULE_SUFFIX, NULL);
552
0
      if (!g_file_test (name, G_FILE_TEST_IS_REGULAR))
553
0
  {
554
0
    g_free (name);
555
0
    name = NULL;
556
0
  }
557
0
    }
558
0
  /* try completing by appending libtool suffix */
559
0
  if (!name)
560
0
    {
561
0
      name = g_strconcat (file_name, ".la", NULL);
562
0
      if (!g_file_test (name, G_FILE_TEST_IS_REGULAR))
563
0
  {
564
0
    g_free (name);
565
0
    name = NULL;
566
0
  }
567
0
    }
568
0
  /* we can't access() the file, lets hope the platform backends finds
569
0
   * it via library paths
570
0
   */
571
0
  if (!name)
572
0
    {
573
0
      gchar *dot = strrchr (file_name, '.');
574
0
      gchar *slash = strrchr (file_name, G_DIR_SEPARATOR);
575
0
      
576
0
      /* make sure the name has a suffix */
577
0
      if (!dot || dot < slash)
578
0
  name = g_strconcat (file_name, "." G_MODULE_SUFFIX, NULL);
579
0
      else
580
0
  name = g_strdup (file_name);
581
0
    }
582
0
583
0
  /* ok, try loading the module */
584
0
  if (name)
585
0
    {
586
0
      /* if it's a libtool archive, figure library file to load */
587
0
      if (str_check_suffix (name, ".la")) /* libtool archive? */
588
0
  {
589
0
    gchar *real_name = parse_libtool_archive (name);
590
0
591
0
    /* real_name might be NULL, but then module error is already set */
592
0
    if (real_name)
593
0
      {
594
0
        g_free (name);
595
0
        name = real_name;
596
0
            }
597
0
  }
598
0
      if (name)
599
0
  handle = _g_module_open (name, (flags & G_MODULE_BIND_LAZY) != 0,
600
0
      (flags & G_MODULE_BIND_LOCAL) != 0);
601
0
    }
602
0
  else
603
0
    {
604
0
      gchar *display_file_name = g_filename_display_name (file_name);
605
0
      g_module_set_error_unduped (g_strdup_printf ("unable to access file \"%s\"", display_file_name));
606
0
      g_free (display_file_name);
607
0
    }
608
0
  g_free (name);
609
0
610
0
  if (handle)
611
0
    {
612
0
      gchar *saved_error;
613
0
      GModuleCheckInit check_init;
614
0
      const gchar *check_failed = NULL;
615
0
      
616
0
      /* search the module list by handle, since file names are not unique */
617
0
      module = g_module_find_by_handle (handle);
618
0
      if (module)
619
0
  {
620
0
    _g_module_close (module->handle, TRUE);
621
0
    module->ref_count++;
622
0
    g_module_set_error (NULL);
623
0
    
624
0
    g_rec_mutex_unlock (&g_module_global_lock);
625
0
    return module;
626
0
  }
627
0
      
628
0
      saved_error = g_strdup (g_module_error ());
629
0
      g_module_set_error (NULL);
630
0
      
631
0
      module = g_new (GModule, 1);
632
0
      module->file_name = g_strdup (file_name);
633
0
      module->handle = handle;
634
0
      module->ref_count = 1;
635
0
      module->is_resident = FALSE;
636
0
      module->unload = NULL;
637
0
      module->next = modules;
638
0
      modules = module;
639
0
      
640
0
      /* check initialization */
641
0
      if (g_module_symbol (module, "g_module_check_init", (gpointer) &check_init) && check_init != NULL)
642
0
  check_failed = check_init (module);
643
0
      
644
0
      /* we don't call unload() if the initialization check failed. */
645
0
      if (!check_failed)
646
0
  g_module_symbol (module, "g_module_unload", (gpointer) &module->unload);
647
0
      
648
0
      if (check_failed)
649
0
  {
650
0
    gchar *error;
651
0
652
0
    error = g_strconcat ("GModule (", file_name, ") ",
653
0
                               "initialization check failed: ",
654
0
                               check_failed, NULL);
655
0
    g_module_close (module);
656
0
    module = NULL;
657
0
    g_module_set_error (error);
658
0
    g_free (error);
659
0
  }
660
0
      else
661
0
  g_module_set_error (saved_error);
662
0
663
0
      g_free (saved_error);
664
0
    }
665
0
666
0
  if (module != NULL &&
667
0
      (module_debug_flags & G_MODULE_DEBUG_RESIDENT_MODULES))
668
0
    g_module_make_resident (module);
669
0
670
0
  g_rec_mutex_unlock (&g_module_global_lock);
671
0
  return module;
672
0
}
673
674
/**
675
 * g_module_close:
676
 * @module: a #GModule to close
677
 *
678
 * Closes a module.
679
 *
680
 * Returns: %TRUE on success
681
 */
682
gboolean
683
g_module_close (GModule *module)
684
0
{
685
0
  SUPPORT_OR_RETURN (FALSE);
686
0
  
687
0
  g_return_val_if_fail (module != NULL, FALSE);
688
0
  g_return_val_if_fail (module->ref_count > 0, FALSE);
689
0
  
690
0
  g_rec_mutex_lock (&g_module_global_lock);
691
0
692
0
  module->ref_count--;
693
0
  
694
0
  if (!module->ref_count && !module->is_resident && module->unload)
695
0
    {
696
0
      GModuleUnload unload;
697
0
698
0
      unload = module->unload;
699
0
      module->unload = NULL;
700
0
      unload (module);
701
0
    }
702
0
703
0
  if (!module->ref_count && !module->is_resident)
704
0
    {
705
0
      GModule *last;
706
0
      GModule *node;
707
0
      
708
0
      last = NULL;
709
0
      
710
0
      node = modules;
711
0
      while (node)
712
0
  {
713
0
    if (node == module)
714
0
      {
715
0
        if (last)
716
0
    last->next = node->next;
717
0
        else
718
0
    modules = node->next;
719
0
        break;
720
0
      }
721
0
    last = node;
722
0
    node = last->next;
723
0
  }
724
0
      module->next = NULL;
725
0
      
726
0
      _g_module_close (module->handle, FALSE);
727
0
      g_free (module->file_name);
728
0
      g_free (module);
729
0
    }
730
0
  
731
0
  g_rec_mutex_unlock (&g_module_global_lock);
732
0
  return g_module_error() == NULL;
733
0
}
734
735
/**
736
 * g_module_make_resident:
737
 * @module: a #GModule to make permanently resident
738
 *
739
 * Ensures that a module will never be unloaded.
740
 * Any future g_module_close() calls on the module will be ignored.
741
 */
742
void
743
g_module_make_resident (GModule *module)
744
0
{
745
0
  g_return_if_fail (module != NULL);
746
0
747
0
  module->is_resident = TRUE;
748
0
}
749
750
/**
751
 * g_module_error:
752
 *
753
 * Gets a string describing the last module error.
754
 *
755
 * Returns: a string describing the last module error
756
 */
757
const gchar *
758
g_module_error (void)
759
0
{
760
0
  return g_private_get (&module_error_private);
761
0
}
762
763
/**
764
 * g_module_symbol:
765
 * @module: a #GModule
766
 * @symbol_name: the name of the symbol to find
767
 * @symbol: (out): returns the pointer to the symbol value
768
 *
769
 * Gets a symbol pointer from a module, such as one exported
770
 * by #G_MODULE_EXPORT. Note that a valid symbol can be %NULL.
771
 *
772
 * Returns: %TRUE on success
773
 */
774
gboolean
775
g_module_symbol (GModule     *module,
776
                 const gchar *symbol_name,
777
                 gpointer    *symbol)
778
0
{
779
0
  const gchar *module_error;
780
0
781
0
  if (symbol)
782
0
    *symbol = NULL;
783
0
  SUPPORT_OR_RETURN (FALSE);
784
0
  
785
0
  g_return_val_if_fail (module != NULL, FALSE);
786
0
  g_return_val_if_fail (symbol_name != NULL, FALSE);
787
0
  g_return_val_if_fail (symbol != NULL, FALSE);
788
0
  
789
0
  g_rec_mutex_lock (&g_module_global_lock);
790
0
791
#ifdef  G_MODULE_NEED_USCORE
792
  {
793
    gchar *name;
794
795
    name = g_strconcat ("_", symbol_name, NULL);
796
    *symbol = _g_module_symbol (module->handle, name);
797
    g_free (name);
798
  }
799
#else /* !G_MODULE_NEED_USCORE */
800
  *symbol = _g_module_symbol (module->handle, symbol_name);
801
0
#endif  /* !G_MODULE_NEED_USCORE */
802
0
  
803
0
  module_error = g_module_error ();
804
0
  if (module_error)
805
0
    {
806
0
      gchar *error;
807
0
808
0
      error = g_strconcat ("'", symbol_name, "': ", module_error, NULL);
809
0
      g_module_set_error (error);
810
0
      g_free (error);
811
0
      *symbol = NULL;
812
0
    }
813
0
  
814
0
  g_rec_mutex_unlock (&g_module_global_lock);
815
0
  return !module_error;
816
0
}
817
818
/**
819
 * g_module_name:
820
 * @module: a #GModule
821
 *
822
 * Returns the filename that the module was opened with.
823
 *
824
 * If @module refers to the application itself, "main" is returned.
825
 *
826
 * Returns: (transfer none): the filename of the module
827
 */
828
const gchar *
829
g_module_name (GModule *module)
830
0
{
831
0
  g_return_val_if_fail (module != NULL, NULL);
832
0
  
833
0
  if (module == main_module)
834
0
    return "main";
835
0
  
836
0
  return module->file_name;
837
0
}
838
839
/**
840
 * g_module_build_path:
841
 * @directory: (nullable): the directory where the module is. This can be
842
 *     %NULL or the empty string to indicate that the standard platform-specific
843
 *     directories will be used, though that is not recommended
844
 * @module_name: the name of the module
845
 *
846
 * A portable way to build the filename of a module. The platform-specific
847
 * prefix and suffix are added to the filename, if needed, and the result
848
 * is added to the directory, using the correct separator character.
849
 *
850
 * The directory should specify the directory where the module can be found.
851
 * It can be %NULL or an empty string to indicate that the module is in a
852
 * standard platform-specific directory, though this is not recommended
853
 * since the wrong module may be found.
854
 *
855
 * For example, calling g_module_build_path() on a Linux system with a
856
 * @directory of `/lib` and a @module_name of "mylibrary" will return
857
 * `/lib/libmylibrary.so`. On a Windows system, using `\Windows` as the
858
 * directory it will return `\Windows\mylibrary.dll`.
859
 *
860
 * Returns: the complete path of the module, including the standard library
861
 *     prefix and suffix. This should be freed when no longer needed
862
 */
863
gchar *
864
g_module_build_path (const gchar *directory,
865
                     const gchar *module_name)
866
0
{
867
0
  g_return_val_if_fail (module_name != NULL, NULL);
868
0
  
869
0
  return _g_module_build_path (directory, module_name);
870
0
}
871
872
873
#ifdef G_OS_WIN32
874
875
/* Binary compatibility versions. Not for newly compiled code. */
876
877
_GLIB_EXTERN GModule *    g_module_open_utf8 (const gchar  *file_name,
878
                                              GModuleFlags  flags);
879
880
_GLIB_EXTERN const gchar *g_module_name_utf8 (GModule      *module);
881
882
GModule*
883
g_module_open_utf8 (const gchar    *file_name,
884
                    GModuleFlags    flags)
885
{
886
  return g_module_open (file_name, flags);
887
}
888
889
const gchar *
890
g_module_name_utf8 (GModule *module)
891
{
892
  return g_module_name (module);
893
}
894
895
#endif