aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/openssl/crypto/dso/dso_win32.c
blob: aa2931376309a99a2e86d0445ff8e9fe8ece6318 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
/*
 * Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the OpenSSL license (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include "e_os.h"
#include "dso_local.h"

#if defined(DSO_WIN32)

# ifdef _WIN32_WCE
#  if _WIN32_WCE < 300
static FARPROC GetProcAddressA(HMODULE hModule, LPCSTR lpProcName)
{
    WCHAR lpProcNameW[64];
    int i;

    for (i = 0; lpProcName[i] && i < 64; i++)
        lpProcNameW[i] = (WCHAR)lpProcName[i];
    if (i == 64)
        return NULL;
    lpProcNameW[i] = 0;

    return GetProcAddressW(hModule, lpProcNameW);
}
#  endif
#  undef GetProcAddress
#  define GetProcAddress GetProcAddressA

static HINSTANCE LoadLibraryA(LPCSTR lpLibFileName)
{
    WCHAR *fnamw;
    size_t len_0 = strlen(lpLibFileName) + 1, i;

#  ifdef _MSC_VER
    fnamw = (WCHAR *)_alloca(len_0 * sizeof(WCHAR));
#  else
    fnamw = (WCHAR *)alloca(len_0 * sizeof(WCHAR));
#  endif
    if (fnamw == NULL) {
        SetLastError(ERROR_NOT_ENOUGH_MEMORY);
        return NULL;
    }
#  if defined(_WIN32_WCE) && _WIN32_WCE>=101
    if (!MultiByteToWideChar(CP_ACP, 0, lpLibFileName, len_0, fnamw, len_0))
#  endif
        for (i = 0; i < len_0; i++)
            fnamw[i] = (WCHAR)lpLibFileName[i];

    return LoadLibraryW(fnamw);
}
# endif

/* Part of the hack in "win32_load" ... */
# define DSO_MAX_TRANSLATED_SIZE 256

static int win32_load(DSO *dso);
static int win32_unload(DSO *dso);
static DSO_FUNC_TYPE win32_bind_func(DSO *dso, const char *symname);
static char *win32_name_converter(DSO *dso, const char *filename);
static char *win32_merger(DSO *dso, const char *filespec1,
                          const char *filespec2);
static int win32_pathbyaddr(void *addr, char *path, int sz); 
static void *win32_globallookup(const char *name);

static const char *openssl_strnchr(const char *string, int c, size_t len);

static DSO_METHOD dso_meth_win32 = {
    "OpenSSL 'win32' shared library method",
    win32_load,
    win32_unload,
    win32_bind_func,
    NULL,                       /* ctrl */
    win32_name_converter,
    win32_merger,
    NULL,                       /* init */
    NULL,                       /* finish */
    win32_pathbyaddr,           /* pathbyaddr */ 
    win32_globallookup
};

DSO_METHOD *DSO_METHOD_openssl(void)
{
    return &dso_meth_win32;
}

/*
 * For this DSO_METHOD, our meth_data STACK will contain; (i) a pointer to
 * the handle (HINSTANCE) returned from LoadLibrary(), and copied.
 */

static int win32_load(DSO *dso)
{
    HINSTANCE h = NULL, *p = NULL;
    /* See applicable comments from dso_dl.c */
    char *filename = DSO_convert_filename(dso, NULL);

    if (filename == NULL) {
        DSOerr(DSO_F_WIN32_LOAD, DSO_R_NO_FILENAME);
        goto err;
    }
    h = LoadLibraryA(filename);
    if (h == NULL) {
        DSOerr(DSO_F_WIN32_LOAD, DSO_R_LOAD_FAILED);
        ERR_add_error_data(3, "filename(", filename, ")");
        goto err;
    }
    p = OPENSSL_malloc(sizeof(*p));
    if (p == NULL) {
        DSOerr(DSO_F_WIN32_LOAD, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    *p = h;
    if (!sk_void_push(dso->meth_data, p)) {
        DSOerr(DSO_F_WIN32_LOAD, DSO_R_STACK_ERROR);
        goto err;
    }
    /* Success */
    dso->loaded_filename = filename;
    return 1;
 err:
    /* Cleanup ! */
    OPENSSL_free(filename);
    OPENSSL_free(p);
    if (h != NULL)
        FreeLibrary(h);
    return 0;
}

static int win32_unload(DSO *dso)
{
    HINSTANCE *p;
    if (dso == NULL) {
        DSOerr(DSO_F_WIN32_UNLOAD, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    if (sk_void_num(dso->meth_data) < 1)
        return 1;
    p = sk_void_pop(dso->meth_data);
    if (p == NULL) {
        DSOerr(DSO_F_WIN32_UNLOAD, DSO_R_NULL_HANDLE);
        return 0;
    }
    if (!FreeLibrary(*p)) {
        DSOerr(DSO_F_WIN32_UNLOAD, DSO_R_UNLOAD_FAILED);
        /*
         * We should push the value back onto the stack in case of a retry.
         */
        sk_void_push(dso->meth_data, p);
        return 0;
    }
    /* Cleanup */
    OPENSSL_free(p);
    return 1;
}

static DSO_FUNC_TYPE win32_bind_func(DSO *dso, const char *symname)
{
    HINSTANCE *ptr;
    union {
        void *p;
        FARPROC f;
    } sym;

    if ((dso == NULL) || (symname == NULL)) {
        DSOerr(DSO_F_WIN32_BIND_FUNC, ERR_R_PASSED_NULL_PARAMETER);
        return NULL;
    }
    if (sk_void_num(dso->meth_data) < 1) {
        DSOerr(DSO_F_WIN32_BIND_FUNC, DSO_R_STACK_ERROR);
        return NULL;
    }
    ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
    if (ptr == NULL) {
        DSOerr(DSO_F_WIN32_BIND_FUNC, DSO_R_NULL_HANDLE);
        return NULL;
    }
    sym.f = GetProcAddress(*ptr, symname);
    if (sym.p == NULL) {
        DSOerr(DSO_F_WIN32_BIND_FUNC, DSO_R_SYM_FAILURE);
        ERR_add_error_data(3, "symname(", symname, ")");
        return NULL;
    }
    return (DSO_FUNC_TYPE)sym.f;
}

struct file_st {
    const char *node;
    int nodelen;
    const char *device;
    int devicelen;
    const char *predir;
    int predirlen;
    const char *dir;
    int dirlen;
    const char *file;
    int filelen;
};

static struct file_st *win32_splitter(DSO *dso, const char *filename,
                                      int assume_last_is_dir)
{
    struct file_st *result = NULL;
    enum { IN_NODE, IN_DEVICE, IN_FILE } position;
    const char *start = filename;
    char last;

    if (!filename) {
        DSOerr(DSO_F_WIN32_SPLITTER, DSO_R_NO_FILENAME);
        return NULL;
    }

    result = OPENSSL_zalloc(sizeof(*result));
    if (result == NULL) {
        DSOerr(DSO_F_WIN32_SPLITTER, ERR_R_MALLOC_FAILURE);
        return NULL;
    }

    position = IN_DEVICE;

    if ((filename[0] == '\\' && filename[1] == '\\')
        || (filename[0] == '/' && filename[1] == '/')) {
        position = IN_NODE;
        filename += 2;
        start = filename;
        result->node = start;
    }

    do {
        last = filename[0];
        switch (last) {
        case ':':
            if (position != IN_DEVICE) {
                DSOerr(DSO_F_WIN32_SPLITTER, DSO_R_INCORRECT_FILE_SYNTAX);
                OPENSSL_free(result);
                return NULL;
            }
            result->device = start;
            result->devicelen = (int)(filename - start);
            position = IN_FILE;
            start = ++filename;
            result->dir = start;
            break;
        case '\\':
        case '/':
            if (position == IN_NODE) {
                result->nodelen = (int)(filename - start);
                position = IN_FILE;
                start = ++filename;
                result->dir = start;
            } else if (position == IN_DEVICE) {
                position = IN_FILE;
                filename++;
                result->dir = start;
                result->dirlen = (int)(filename - start);
                start = filename;
            } else {
                filename++;
                result->dirlen += (int)(filename - start);
                start = filename;
            }
            break;
        case '\0':
            if (position == IN_NODE) {
                result->nodelen = (int)(filename - start);
            } else {
                if (filename - start > 0) {
                    if (assume_last_is_dir) {
                        if (position == IN_DEVICE) {
                            result->dir = start;
                            result->dirlen = 0;
                        }
                        result->dirlen += (int)(filename - start);
                    } else {
                        result->file = start;
                        result->filelen = (int)(filename - start);
                    }
                }
            }
            break;
        default:
            filename++;
            break;
        }
    }
    while (last);

    if (!result->nodelen)
        result->node = NULL;
    if (!result->devicelen)
        result->device = NULL;
    if (!result->dirlen)
        result->dir = NULL;
    if (!result->filelen)
        result->file = NULL;

    return result;
}

static char *win32_joiner(DSO *dso, const struct file_st *file_split)
{
    int len = 0, offset = 0;
    char *result = NULL;
    const char *start;

    if (!file_split) {
        DSOerr(DSO_F_WIN32_JOINER, ERR_R_PASSED_NULL_PARAMETER);
        return NULL;
    }
    if (file_split->node) {
        len += 2 + file_split->nodelen; /* 2 for starting \\ */
        if (file_split->predir || file_split->dir || file_split->file)
            len++;              /* 1 for ending \ */
    } else if (file_split->device) {
        len += file_split->devicelen + 1; /* 1 for ending : */
    }
    len += file_split->predirlen;
    if (file_split->predir && (file_split->dir || file_split->file)) {
        len++;                  /* 1 for ending \ */
    }
    len += file_split->dirlen;
    if (file_split->dir && file_split->file) {
        len++;                  /* 1 for ending \ */
    }
    len += file_split->filelen;

    if (!len) {
        DSOerr(DSO_F_WIN32_JOINER, DSO_R_EMPTY_FILE_STRUCTURE);
        return NULL;
    }

    result = OPENSSL_malloc(len + 1);
    if (result == NULL) {
        DSOerr(DSO_F_WIN32_JOINER, ERR_R_MALLOC_FAILURE);
        return NULL;
    }

    if (file_split->node) {
        strcpy(&result[offset], "\\\\");
        offset += 2;
        strncpy(&result[offset], file_split->node, file_split->nodelen);
        offset += file_split->nodelen;
        if (file_split->predir || file_split->dir || file_split->file) {
            result[offset] = '\\';
            offset++;
        }
    } else if (file_split->device) {
        strncpy(&result[offset], file_split->device, file_split->devicelen);
        offset += file_split->devicelen;
        result[offset] = ':';
        offset++;
    }
    start = file_split->predir;
    while (file_split->predirlen > (start - file_split->predir)) {
        const char *end = openssl_strnchr(start, '/',
                                          file_split->predirlen - (start -
                                                                   file_split->predir));
        if (!end)
            end = start
                + file_split->predirlen - (start - file_split->predir);
        strncpy(&result[offset], start, end - start);
        offset += (int)(end - start);
        result[offset] = '\\';
        offset++;
        start = end + 1;
    }
    start = file_split->dir;
    while (file_split->dirlen > (start - file_split->dir)) {
        const char *end = openssl_strnchr(start, '/',
                                          file_split->dirlen - (start -
                                                                file_split->dir));
        if (!end)
            end = start + file_split->dirlen - (start - file_split->dir);
        strncpy(&result[offset], start, end - start);
        offset += (int)(end - start);
        result[offset] = '\\';
        offset++;
        start = end + 1;
    }
    strncpy(&result[offset], file_split->file, file_split->filelen);
    offset += file_split->filelen;
    result[offset] = '\0';
    return result;
}

static char *win32_merger(DSO *dso, const char *filespec1,
                          const char *filespec2)
{
    char *merged = NULL;
    struct file_st *filespec1_split = NULL;
    struct file_st *filespec2_split = NULL;

    if (!filespec1 && !filespec2) {
        DSOerr(DSO_F_WIN32_MERGER, ERR_R_PASSED_NULL_PARAMETER);
        return NULL;
    }
    if (!filespec2) {
        merged = OPENSSL_strdup(filespec1);
        if (merged == NULL) {
            DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
            return NULL;
        }
    } else if (!filespec1) {
        merged = OPENSSL_strdup(filespec2);
        if (merged == NULL) {
            DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
            return NULL;
        }
    } else {
        filespec1_split = win32_splitter(dso, filespec1, 0);
        if (!filespec1_split) {
            DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
            return NULL;
        }
        filespec2_split = win32_splitter(dso, filespec2, 1);
        if (!filespec2_split) {
            DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
            OPENSSL_free(filespec1_split);
            return NULL;
        }

        /* Fill in into filespec1_split */
        if (!filespec1_split->node && !filespec1_split->device) {
            filespec1_split->node = filespec2_split->node;
            filespec1_split->nodelen = filespec2_split->nodelen;
            filespec1_split->device = filespec2_split->device;
            filespec1_split->devicelen = filespec2_split->devicelen;
        }
        if (!filespec1_split->dir) {
            filespec1_split->dir = filespec2_split->dir;
            filespec1_split->dirlen = filespec2_split->dirlen;
        } else if (filespec1_split->dir[0] != '\\'
                   && filespec1_split->dir[0] != '/') {
            filespec1_split->predir = filespec2_split->dir;
            filespec1_split->predirlen = filespec2_split->dirlen;
        }
        if (!filespec1_split->file) {
            filespec1_split->file = filespec2_split->file;
            filespec1_split->filelen = filespec2_split->filelen;
        }

        merged = win32_joiner(dso, filespec1_split);
    }
    OPENSSL_free(filespec1_split);
    OPENSSL_free(filespec2_split);
    return merged;
}

static char *win32_name_converter(DSO *dso, const char *filename)
{
    char *translated;
    int len, transform;

    len = strlen(filename);
    transform = ((strstr(filename, "/") == NULL) &&
                 (strstr(filename, "\\") == NULL) &&
                 (strstr(filename, ":") == NULL));
    if (transform)
        /* We will convert this to "%s.dll" */
        translated = OPENSSL_malloc(len + 5);
    else
        /* We will simply duplicate filename */
        translated = OPENSSL_malloc(len + 1);
    if (translated == NULL) {
        DSOerr(DSO_F_WIN32_NAME_CONVERTER, DSO_R_NAME_TRANSLATION_FAILED);
        return NULL;
    }
    if (transform)
        sprintf(translated, "%s.dll", filename);
    else
        sprintf(translated, "%s", filename);
    return translated;
}

static const char *openssl_strnchr(const char *string, int c, size_t len)
{
    size_t i;
    const char *p;
    for (i = 0, p = string; i < len && *p; i++, p++) {
        if (*p == c)
            return p;
    }
    return NULL;
}

# include <tlhelp32.h>
# ifdef _WIN32_WCE
#  define DLLNAME "TOOLHELP.DLL"
# else
#  ifdef MODULEENTRY32
#   undef MODULEENTRY32         /* unmask the ASCII version! */
#  endif
#  define DLLNAME "KERNEL32.DLL"
# endif

typedef HANDLE(WINAPI *CREATETOOLHELP32SNAPSHOT) (DWORD, DWORD);
typedef BOOL(WINAPI *CLOSETOOLHELP32SNAPSHOT) (HANDLE);
typedef BOOL(WINAPI *MODULE32) (HANDLE, MODULEENTRY32 *);

static int win32_pathbyaddr(void *addr, char *path, int sz) 
{ 
    HMODULE dll; 
    HANDLE hModuleSnap = INVALID_HANDLE_VALUE; 
    MODULEENTRY32 me32; 
    CREATETOOLHELP32SNAPSHOT create_snap; 
    CLOSETOOLHELP32SNAPSHOT close_snap; 
    MODULE32 module_first, module_next; 
 
    if (addr == NULL) { 
        union { 
            int (*f) (void *, char *, int); 
            void *p; 
        } t = { 
            win32_pathbyaddr 
        }; 
        addr = t.p; 
    } 
 
    dll = LoadLibrary(TEXT(DLLNAME)); 
    if (dll == NULL) { 
        DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_UNSUPPORTED); 
        return -1; 
    } 
 
    create_snap = (CREATETOOLHELP32SNAPSHOT) 
        GetProcAddress(dll, "CreateToolhelp32Snapshot"); 
    if (create_snap == NULL) { 
        FreeLibrary(dll); 
        DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_UNSUPPORTED); 
        return -1; 
    } 
    /* We take the rest for granted... */ 
# ifdef _WIN32_WCE 
    close_snap = (CLOSETOOLHELP32SNAPSHOT) 
        GetProcAddress(dll, "CloseToolhelp32Snapshot"); 
# else 
    close_snap = (CLOSETOOLHELP32SNAPSHOT) CloseHandle; 
# endif 
    module_first = (MODULE32) GetProcAddress(dll, "Module32First"); 
    module_next = (MODULE32) GetProcAddress(dll, "Module32Next"); 
 
    /* 
     * Take a snapshot of current process which includes 
     * list of all involved modules. 
     */ 
    hModuleSnap = (*create_snap) (TH32CS_SNAPMODULE, 0); 
    if (hModuleSnap == INVALID_HANDLE_VALUE) { 
        FreeLibrary(dll); 
        DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_UNSUPPORTED); 
        return -1; 
    } 
 
    me32.dwSize = sizeof(me32); 
 
    if (!(*module_first) (hModuleSnap, &me32)) { 
        (*close_snap) (hModuleSnap); 
        FreeLibrary(dll); 
        DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_FAILURE); 
        return -1; 
    } 
 
    /* Enumerate the modules to find one which includes me. */ 
    do { 
        if ((size_t) addr >= (size_t) me32.modBaseAddr &&
            (size_t) addr < (size_t) (me32.modBaseAddr + me32.modBaseSize)) {
            (*close_snap) (hModuleSnap); 
            FreeLibrary(dll); 
# ifdef _WIN32_WCE 
#  if _WIN32_WCE >= 101 
            return WideCharToMultiByte(CP_ACP, 0, me32.szExePath, -1, 
                                       path, sz, NULL, NULL); 
#  else 
            { 
                int i, len = (int)wcslen(me32.szExePath); 
                if (sz <= 0) 
                    return len + 1; 
                if (len >= sz) 
                    len = sz - 1; 
                for (i = 0; i < len; i++) 
                    path[i] = (char)me32.szExePath[i]; 
                path[len++] = '\0'; 
                return len; 
            } 
#  endif 
# else 
            { 
                int len = (int)strlen(me32.szExePath); 
                if (sz <= 0) 
                    return len + 1; 
                if (len >= sz) 
                    len = sz - 1; 
                memcpy(path, me32.szExePath, len); 
                path[len++] = '\0'; 
                return len; 
            } 
# endif 
        } 
    } while ((*module_next) (hModuleSnap, &me32)); 
 
    (*close_snap) (hModuleSnap); 
    FreeLibrary(dll); 
    return 0; 
} 
 
static void *win32_globallookup(const char *name)
{
    HMODULE dll;
    HANDLE hModuleSnap = INVALID_HANDLE_VALUE;
    MODULEENTRY32 me32;
    CREATETOOLHELP32SNAPSHOT create_snap;
    CLOSETOOLHELP32SNAPSHOT close_snap;
    MODULE32 module_first, module_next;
    union {
        void *p;
        FARPROC f;
    } ret = { NULL };

    dll = LoadLibrary(TEXT(DLLNAME));
    if (dll == NULL) {
        DSOerr(DSO_F_WIN32_GLOBALLOOKUP, DSO_R_UNSUPPORTED);
        return NULL;
    }

    create_snap = (CREATETOOLHELP32SNAPSHOT)
        GetProcAddress(dll, "CreateToolhelp32Snapshot");
    if (create_snap == NULL) {
        FreeLibrary(dll);
        DSOerr(DSO_F_WIN32_GLOBALLOOKUP, DSO_R_UNSUPPORTED);
        return NULL;
    }
    /* We take the rest for granted... */
# ifdef _WIN32_WCE
    close_snap = (CLOSETOOLHELP32SNAPSHOT)
        GetProcAddress(dll, "CloseToolhelp32Snapshot");
# else
    close_snap = (CLOSETOOLHELP32SNAPSHOT) CloseHandle;
# endif
    module_first = (MODULE32) GetProcAddress(dll, "Module32First");
    module_next = (MODULE32) GetProcAddress(dll, "Module32Next");

    hModuleSnap = (*create_snap) (TH32CS_SNAPMODULE, 0);
    if (hModuleSnap == INVALID_HANDLE_VALUE) {
        FreeLibrary(dll);
        DSOerr(DSO_F_WIN32_GLOBALLOOKUP, DSO_R_UNSUPPORTED);
        return NULL;
    }

    me32.dwSize = sizeof(me32);

    if (!(*module_first) (hModuleSnap, &me32)) {
        (*close_snap) (hModuleSnap);
        FreeLibrary(dll);
        return NULL;
    }

    do {
        if ((ret.f = GetProcAddress(me32.hModule, name))) {
            (*close_snap) (hModuleSnap);
            FreeLibrary(dll);
            return ret.p;
        }
    } while ((*module_next) (hModuleSnap, &me32));

    (*close_snap) (hModuleSnap);
    FreeLibrary(dll);
    return NULL;
}
#endif                          /* DSO_WIN32 */