crypto/dso/dso_win32.c

   1 /*
   2  * Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
   3  * 2000.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in
  17  *    the documentation and/or other materials provided with the
  18  *    distribution.
  19  *
  20  * 3. All advertising materials mentioning features or use of this
  21  *    software must display the following acknowledgment:
  22  *    "This product includes software developed by the OpenSSL Project
  23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  24  *
  25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  26  *    endorse or promote products derived from this software without
  27  *    prior written permission. For written permission, please contact
  28  *    licensing@OpenSSL.org.
  29  *
  30  * 5. Products derived from this software may not be called "OpenSSL"
  31  *    nor may "OpenSSL" appear in their names without prior written
  32  *    permission of the OpenSSL Project.
  33  *
  34  * 6. Redistributions of any form whatsoever must retain the following
  35  *    acknowledgment:
  36  *    "This product includes software developed by the OpenSSL Project
  37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  38  *
  39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  50  * OF THE POSSIBILITY OF SUCH DAMAGE.
  51  * ====================================================================
  52  *
  53  * This product includes cryptographic software written by Eric Young
  54  * (eay@cryptsoft.com).  This product includes software written by Tim
  55  * Hudson (tjh@cryptsoft.com).
  56  *
  57  */
  58
  59 #include "dso_locl.h"
  60
  61 #if defined(DSO_WIN32)
  62
  63 # ifdef _WIN32_WCE
  64 #  if _WIN32_WCE < 300
  65 static FARPROC GetProcAddressA(HMODULE hModule, LPCSTR lpProcName)
  66 {
  67     WCHAR lpProcNameW[64];
  68     int i;
  69
  70     for (i = 0; lpProcName[i] && i < 64; i++)
  71         lpProcNameW[i] = (WCHAR)lpProcName[i];
  72     if (i == 64)
  73         return NULL;
  74     lpProcNameW[i] = 0;
  75
  76     return GetProcAddressW(hModule, lpProcNameW);
  77 }
  78 #  endif
  79 #  undef GetProcAddress
  80 #  define GetProcAddress GetProcAddressA
  81
  82 static HINSTANCE LoadLibraryA(LPCSTR lpLibFileName)
  83 {
  84     WCHAR *fnamw;
  85     size_t len_0 = strlen(lpLibFileName) + 1, i;
  86
  87 #  ifdef _MSC_VER
  88     fnamw = (WCHAR *)_alloca(len_0 * sizeof(WCHAR));
  89 #  else
  90     fnamw = (WCHAR *)alloca(len_0 * sizeof(WCHAR));
  91 #  endif
  92     if (fnamw == NULL) {
  93         SetLastError(ERROR_NOT_ENOUGH_MEMORY);
  94         return NULL;
  95     }
  96 #  if defined(_WIN32_WCE) && _WIN32_WCE>=101
  97     if (!MultiByteToWideChar(CP_ACP, 0, lpLibFileName, len_0, fnamw, len_0))
  98 #  endif
  99         for (i = 0; i < len_0; i++)
 100             fnamw[i] = (WCHAR)lpLibFileName[i];
 101
 102     return LoadLibraryW(fnamw);
 103 }
 104 # endif
 105
 106 /* Part of the hack in "win32_load" ... */
 107 # define DSO_MAX_TRANSLATED_SIZE 256
 108
 109 static int win32_load(DSO *dso);
 110 static int win32_unload(DSO *dso);
 111 static void *win32_bind_var(DSO *dso, const char *symname);
 112 static DSO_FUNC_TYPE win32_bind_func(DSO *dso, const char *symname);
 113 static char *win32_name_converter(DSO *dso, const char *filename);
 114 static char *win32_merger(DSO *dso, const char *filespec1,
 115                           const char *filespec2);
 116 static int win32_pathbyaddr(void *addr, char *path, int sz);
 117 static void *win32_globallookup(const char *name);
 118
 119 static const char *openssl_strnchr(const char *string, int c, size_t len);
 120
 121 static DSO_METHOD dso_meth_win32 = {
 122     "OpenSSL 'win32' shared library method",
 123     win32_load,
 124     win32_unload,
 125     win32_bind_var,
 126     win32_bind_func,
 127     NULL,                       /* ctrl */
 128     win32_name_converter,
 129     win32_merger,
 130     NULL,                       /* init */
 131     NULL,                       /* finish */
 132     win32_pathbyaddr,
 133     win32_globallookup
 134 };
 135
 136 DSO_METHOD *DSO_METHOD_openssl(void)
 137 {
 138     return &dso_meth_win32;
 139 }
 140
 141 /*
 142  * For this DSO_METHOD, our meth_data STACK will contain; (i) a pointer to
 143  * the handle (HINSTANCE) returned from LoadLibrary(), and copied.
 144  */
 145
 146 static int win32_load(DSO *dso)
 147 {
 148     HINSTANCE h = NULL, *p = NULL;
 149     /* See applicable comments from dso_dl.c */
 150     char *filename = DSO_convert_filename(dso, NULL);
 151
 152     if (filename == NULL) {
 153         DSOerr(DSO_F_WIN32_LOAD, DSO_R_NO_FILENAME);
 154         goto err;
 155     }
 156     h = LoadLibraryA(filename);
 157     if (h == NULL) {
 158         DSOerr(DSO_F_WIN32_LOAD, DSO_R_LOAD_FAILED);
 159         ERR_add_error_data(3, "filename(", filename, ")");
 160         goto err;
 161     }
 162     p = OPENSSL_malloc(sizeof(*p));
 163     if (p == NULL) {
 164         DSOerr(DSO_F_WIN32_LOAD, ERR_R_MALLOC_FAILURE);
 165         goto err;
 166     }
 167     *p = h;
 168     if (!sk_void_push(dso->meth_data, p)) {
 169         DSOerr(DSO_F_WIN32_LOAD, DSO_R_STACK_ERROR);
 170         goto err;
 171     }
 172     /* Success */
 173     dso->loaded_filename = filename;
 174     return (1);
 175  err:
 176     /* Cleanup ! */
 177     OPENSSL_free(filename);
 178     OPENSSL_free(p);
 179     if (h != NULL)
 180         FreeLibrary(h);
 181     return (0);
 182 }
 183
 184 static int win32_unload(DSO *dso)
 185 {
 186     HINSTANCE *p;
 187     if (dso == NULL) {
 188         DSOerr(DSO_F_WIN32_UNLOAD, ERR_R_PASSED_NULL_PARAMETER);
 189         return (0);
 190     }
 191     if (sk_void_num(dso->meth_data) < 1)
 192         return (1);
 193     p = sk_void_pop(dso->meth_data);
 194     if (p == NULL) {
 195         DSOerr(DSO_F_WIN32_UNLOAD, DSO_R_NULL_HANDLE);
 196         return (0);
 197     }
 198     if (!FreeLibrary(*p)) {
 199         DSOerr(DSO_F_WIN32_UNLOAD, DSO_R_UNLOAD_FAILED);
 200         /*
 201          * We should push the value back onto the stack in case of a retry.
 202          */
 203         sk_void_push(dso->meth_data, p);
 204         return (0);
 205     }
 206     /* Cleanup */
 207     OPENSSL_free(p);
 208     return (1);
 209 }
 210
 211 /*
 212  * Using GetProcAddress for variables? TODO: Check this out in the Win32 API
 213  * docs, there's probably a variant for variables.
 214  */
 215 static void *win32_bind_var(DSO *dso, const char *symname)
 216 {
 217     HINSTANCE *ptr;
 218     union {
 219         void *p;
 220         FARPROC f;
 221     } sym;
 222
 223     if ((dso == NULL) || (symname == NULL)) {
 224         DSOerr(DSO_F_WIN32_BIND_VAR, ERR_R_PASSED_NULL_PARAMETER);
 225         return (NULL);
 226     }
 227     if (sk_void_num(dso->meth_data) < 1) {
 228         DSOerr(DSO_F_WIN32_BIND_VAR, DSO_R_STACK_ERROR);
 229         return (NULL);
 230     }
 231     ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
 232     if (ptr == NULL) {
 233         DSOerr(DSO_F_WIN32_BIND_VAR, DSO_R_NULL_HANDLE);
 234         return (NULL);
 235     }
 236     sym.f = GetProcAddress(*ptr, symname);
 237     if (sym.p == NULL) {
 238         DSOerr(DSO_F_WIN32_BIND_VAR, DSO_R_SYM_FAILURE);
 239         ERR_add_error_data(3, "symname(", symname, ")");
 240         return (NULL);
 241     }
 242     return (sym.p);
 243 }
 244
 245 static DSO_FUNC_TYPE win32_bind_func(DSO *dso, const char *symname)
 246 {
 247     HINSTANCE *ptr;
 248     union {
 249         void *p;
 250         FARPROC f;
 251     } sym;
 252
 253     if ((dso == NULL) || (symname == NULL)) {
 254         DSOerr(DSO_F_WIN32_BIND_FUNC, ERR_R_PASSED_NULL_PARAMETER);
 255         return (NULL);
 256     }
 257     if (sk_void_num(dso->meth_data) < 1) {
 258         DSOerr(DSO_F_WIN32_BIND_FUNC, DSO_R_STACK_ERROR);
 259         return (NULL);
 260     }
 261     ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
 262     if (ptr == NULL) {
 263         DSOerr(DSO_F_WIN32_BIND_FUNC, DSO_R_NULL_HANDLE);
 264         return (NULL);
 265     }
 266     sym.f = GetProcAddress(*ptr, symname);
 267     if (sym.p == NULL) {
 268         DSOerr(DSO_F_WIN32_BIND_FUNC, DSO_R_SYM_FAILURE);
 269         ERR_add_error_data(3, "symname(", symname, ")");
 270         return (NULL);
 271     }
 272     return ((DSO_FUNC_TYPE)sym.f);
 273 }
 274
 275 struct file_st {
 276     const char *node;
 277     int nodelen;
 278     const char *device;
 279     int devicelen;
 280     const char *predir;
 281     int predirlen;
 282     const char *dir;
 283     int dirlen;
 284     const char *file;
 285     int filelen;
 286 };
 287
 288 static struct file_st *win32_splitter(DSO *dso, const char *filename,
 289                                       int assume_last_is_dir)
 290 {
 291     struct file_st *result = NULL;
 292     enum { IN_NODE, IN_DEVICE, IN_FILE } position;
 293     const char *start = filename;
 294     char last;
 295
 296     if (!filename) {
 297         DSOerr(DSO_F_WIN32_SPLITTER, DSO_R_NO_FILENAME);
 298         /*
 299          * goto err;
 300          */
 301         return (NULL);
 302     }
 303
 304     result = OPENSSL_zalloc(sizeof(*result));
 305     if (result == NULL) {
 306         DSOerr(DSO_F_WIN32_SPLITTER, ERR_R_MALLOC_FAILURE);
 307         return (NULL);
 308     }
 309
 310     position = IN_DEVICE;
 311
 312     if ((filename[0] == '\\' && filename[1] == '\\')
 313         || (filename[0] == '/' && filename[1] == '/')) {
 314         position = IN_NODE;
 315         filename += 2;
 316         start = filename;
 317         result->node = start;
 318     }
 319
 320     do {
 321         last = filename[0];
 322         switch (last) {
 323         case ':':
 324             if (position != IN_DEVICE) {
 325                 DSOerr(DSO_F_WIN32_SPLITTER, DSO_R_INCORRECT_FILE_SYNTAX);
 326                 /*
 327                  * goto err;
 328                  */
 329                 OPENSSL_free(result);
 330                 return (NULL);
 331             }
 332             result->device = start;
 333             result->devicelen = (int)(filename - start);
 334             position = IN_FILE;
 335             start = ++filename;
 336             result->dir = start;
 337             break;
 338         case '\\':
 339         case '/':
 340             if (position == IN_NODE) {
 341                 result->nodelen = (int)(filename - start);
 342                 position = IN_FILE;
 343                 start = ++filename;
 344                 result->dir = start;
 345             } else if (position == IN_DEVICE) {
 346                 position = IN_FILE;
 347                 filename++;
 348                 result->dir = start;
 349                 result->dirlen = (int)(filename - start);
 350                 start = filename;
 351             } else {
 352                 filename++;
 353                 result->dirlen += (int)(filename - start);
 354                 start = filename;
 355             }
 356             break;
 357         case '\0':
 358             if (position == IN_NODE) {
 359                 result->nodelen = (int)(filename - start);
 360             } else {
 361                 if (filename - start > 0) {
 362                     if (assume_last_is_dir) {
 363                         if (position == IN_DEVICE) {
 364                             result->dir = start;
 365                             result->dirlen = 0;
 366                         }
 367                         result->dirlen += (int)(filename - start);
 368                     } else {
 369                         result->file = start;
 370                         result->filelen = (int)(filename - start);
 371                     }
 372                 }
 373             }
 374             break;
 375         default:
 376             filename++;
 377             break;
 378         }
 379     }
 380     while (last);
 381
 382     if (!result->nodelen)
 383         result->node = NULL;
 384     if (!result->devicelen)
 385         result->device = NULL;
 386     if (!result->dirlen)
 387         result->dir = NULL;
 388     if (!result->filelen)
 389         result->file = NULL;
 390
 391     return (result);
 392 }
 393
 394 static char *win32_joiner(DSO *dso, const struct file_st *file_split)
 395 {
 396     int len = 0, offset = 0;
 397     char *result = NULL;
 398     const char *start;
 399
 400     if (!file_split) {
 401         DSOerr(DSO_F_WIN32_JOINER, ERR_R_PASSED_NULL_PARAMETER);
 402         return (NULL);
 403     }
 404     if (file_split->node) {
 405         len += 2 + file_split->nodelen; /* 2 for starting \\ */
 406         if (file_split->predir || file_split->dir || file_split->file)
 407             len++;              /* 1 for ending \ */
 408     } else if (file_split->device) {
 409         len += file_split->devicelen + 1; /* 1 for ending : */
 410     }
 411     len += file_split->predirlen;
 412     if (file_split->predir && (file_split->dir || file_split->file)) {
 413         len++;                  /* 1 for ending \ */
 414     }
 415     len += file_split->dirlen;
 416     if (file_split->dir && file_split->file) {
 417         len++;                  /* 1 for ending \ */
 418     }
 419     len += file_split->filelen;
 420
 421     if (!len) {
 422         DSOerr(DSO_F_WIN32_JOINER, DSO_R_EMPTY_FILE_STRUCTURE);
 423         return (NULL);
 424     }
 425
 426     result = OPENSSL_malloc(len + 1);
 427     if (result == NULL) {
 428         DSOerr(DSO_F_WIN32_JOINER, ERR_R_MALLOC_FAILURE);
 429         return (NULL);
 430     }
 431
 432     if (file_split->node) {
 433         strcpy(&result[offset], "\\\\");
 434         offset += 2;
 435         strncpy(&result[offset], file_split->node, file_split->nodelen);
 436         offset += file_split->nodelen;
 437         if (file_split->predir || file_split->dir || file_split->file) {
 438             result[offset] = '\\';
 439             offset++;
 440         }
 441     } else if (file_split->device) {
 442         strncpy(&result[offset], file_split->device, file_split->devicelen);
 443         offset += file_split->devicelen;
 444         result[offset] = ':';
 445         offset++;
 446     }
 447     start = file_split->predir;
 448     while (file_split->predirlen > (start - file_split->predir)) {
 449         const char *end = openssl_strnchr(start, '/',
 450                                           file_split->predirlen - (start -
 451                                                                    file_split->predir));
 452         if (!end)
 453             end = start
 454                 + file_split->predirlen - (start - file_split->predir);
 455         strncpy(&result[offset], start, end - start);
 456         offset += (int)(end - start);
 457         result[offset] = '\\';
 458         offset++;
 459         start = end + 1;
 460     }
 461     start = file_split->dir;
 462     while (file_split->dirlen > (start - file_split->dir)) {
 463         const char *end = openssl_strnchr(start, '/',
 464                                           file_split->dirlen - (start -
 465                                                                 file_split->dir));
 466         if (!end)
 467             end = start + file_split->dirlen - (start - file_split->dir);
 468         strncpy(&result[offset], start, end - start);
 469         offset += (int)(end - start);
 470         result[offset] = '\\';
 471         offset++;
 472         start = end + 1;
 473     }
 474     strncpy(&result[offset], file_split->file, file_split->filelen);
 475     offset += file_split->filelen;
 476     result[offset] = '\0';
 477     return (result);
 478 }
 479
 480 static char *win32_merger(DSO *dso, const char *filespec1,
 481                           const char *filespec2)
 482 {
 483     char *merged = NULL;
 484     struct file_st *filespec1_split = NULL;
 485     struct file_st *filespec2_split = NULL;
 486
 487     if (!filespec1 && !filespec2) {
 488         DSOerr(DSO_F_WIN32_MERGER, ERR_R_PASSED_NULL_PARAMETER);
 489         return (NULL);
 490     }
 491     if (!filespec2) {
 492         merged = OPENSSL_malloc(strlen(filespec1) + 1);
 493         if (merged == NULL) {
 494             DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
 495             return (NULL);
 496         }
 497         strcpy(merged, filespec1);
 498     } else if (!filespec1) {
 499         merged = OPENSSL_malloc(strlen(filespec2) + 1);
 500         if (merged == NULL) {
 501             DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
 502             return (NULL);
 503         }
 504         strcpy(merged, filespec2);
 505     } else {
 506         filespec1_split = win32_splitter(dso, filespec1, 0);
 507         if (!filespec1_split) {
 508             DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
 509             return (NULL);
 510         }
 511         filespec2_split = win32_splitter(dso, filespec2, 1);
 512         if (!filespec2_split) {
 513             DSOerr(DSO_F_WIN32_MERGER, ERR_R_MALLOC_FAILURE);
 514             OPENSSL_free(filespec1_split);
 515             return (NULL);
 516         }
 517
 518         /* Fill in into filespec1_split */
 519         if (!filespec1_split->node && !filespec1_split->device) {
 520             filespec1_split->node = filespec2_split->node;
 521             filespec1_split->nodelen = filespec2_split->nodelen;
 522             filespec1_split->device = filespec2_split->device;
 523             filespec1_split->devicelen = filespec2_split->devicelen;
 524         }
 525         if (!filespec1_split->dir) {
 526             filespec1_split->dir = filespec2_split->dir;
 527             filespec1_split->dirlen = filespec2_split->dirlen;
 528         } else if (filespec1_split->dir[0] != '\\'
 529                    && filespec1_split->dir[0] != '/') {
 530             filespec1_split->predir = filespec2_split->dir;
 531             filespec1_split->predirlen = filespec2_split->dirlen;
 532         }
 533         if (!filespec1_split->file) {
 534             filespec1_split->file = filespec2_split->file;
 535             filespec1_split->filelen = filespec2_split->filelen;
 536         }
 537
 538         merged = win32_joiner(dso, filespec1_split);
 539     }
 540     OPENSSL_free(filespec1_split);
 541     OPENSSL_free(filespec2_split);
 542     return (merged);
 543 }
 544
 545 static char *win32_name_converter(DSO *dso, const char *filename)
 546 {
 547     char *translated;
 548     int len, transform;
 549
 550     len = strlen(filename);
 551     transform = ((strstr(filename, "/") == NULL) &&
 552                  (strstr(filename, "\\") == NULL) &&
 553                  (strstr(filename, ":") == NULL));
 554     if (transform)
 555         /* We will convert this to "%s.dll" */
 556         translated = OPENSSL_malloc(len + 5);
 557     else
 558         /* We will simply duplicate filename */
 559         translated = OPENSSL_malloc(len + 1);
 560     if (translated == NULL) {
 561         DSOerr(DSO_F_WIN32_NAME_CONVERTER, DSO_R_NAME_TRANSLATION_FAILED);
 562         return (NULL);
 563     }
 564     if (transform)
 565         sprintf(translated, "%s.dll", filename);
 566     else
 567         sprintf(translated, "%s", filename);
 568     return (translated);
 569 }
 570
 571 static const char *openssl_strnchr(const char *string, int c, size_t len)
 572 {
 573     size_t i;
 574     const char *p;
 575     for (i = 0, p = string; i < len && *p; i++, p++) {
 576         if (*p == c)
 577             return p;
 578     }
 579     return NULL;
 580 }
 581
 582 # include <tlhelp32.h>
 583 # ifdef _WIN32_WCE
 584 #  define DLLNAME "TOOLHELP.DLL"
 585 # else
 586 #  ifdef MODULEENTRY32
 587 #   undef MODULEENTRY32         /* unmask the ASCII version! */
 588 #  endif
 589 #  define DLLNAME "KERNEL32.DLL"
 590 # endif
 591
 592 typedef HANDLE(WINAPI *CREATETOOLHELP32SNAPSHOT) (DWORD, DWORD);
 593 typedef BOOL(WINAPI *CLOSETOOLHELP32SNAPSHOT) (HANDLE);
 594 typedef BOOL(WINAPI *MODULE32) (HANDLE, MODULEENTRY32 *);
 595
 596 static int win32_pathbyaddr(void *addr, char *path, int sz)
 597 {
 598     HMODULE dll;
 599     HANDLE hModuleSnap = INVALID_HANDLE_VALUE;
 600     MODULEENTRY32 me32;
 601     CREATETOOLHELP32SNAPSHOT create_snap;
 602     CLOSETOOLHELP32SNAPSHOT close_snap;
 603     MODULE32 module_first, module_next;
 604
 605     if (addr == NULL) {
 606         union {
 607             int (*f) (void *, char *, int);
 608             void *p;
 609         } t = {
 610             win32_pathbyaddr
 611         };
 612         addr = t.p;
 613     }
 614
 615     dll = LoadLibrary(TEXT(DLLNAME));
 616     if (dll == NULL) {
 617         DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_UNSUPPORTED);
 618         return -1;
 619     }
 620
 621     create_snap = (CREATETOOLHELP32SNAPSHOT)
 622         GetProcAddress(dll, "CreateToolhelp32Snapshot");
 623     if (create_snap == NULL) {
 624         FreeLibrary(dll);
 625         DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_UNSUPPORTED);
 626         return -1;
 627     }
 628     /* We take the rest for granted... */
 629 # ifdef _WIN32_WCE
 630     close_snap = (CLOSETOOLHELP32SNAPSHOT)
 631         GetProcAddress(dll, "CloseToolhelp32Snapshot");
 632 # else
 633     close_snap = (CLOSETOOLHELP32SNAPSHOT) CloseHandle;
 634 # endif
 635     module_first = (MODULE32) GetProcAddress(dll, "Module32First");
 636     module_next = (MODULE32) GetProcAddress(dll, "Module32Next");
 637
 638     hModuleSnap = (*create_snap) (TH32CS_SNAPMODULE, 0);
 639     if (hModuleSnap == INVALID_HANDLE_VALUE) {
 640         FreeLibrary(dll);
 641         DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_UNSUPPORTED);
 642         return -1;
 643     }
 644
 645     me32.dwSize = sizeof(me32);
 646
 647     if (!(*module_first) (hModuleSnap, &me32)) {
 648         (*close_snap) (hModuleSnap);
 649         FreeLibrary(dll);
 650         DSOerr(DSO_F_WIN32_PATHBYADDR, DSO_R_FAILURE);
 651         return -1;
 652     }
 653
 654     do {
 655         if ((BYTE *) addr >= me32.modBaseAddr &&
 656             (BYTE *) addr < me32.modBaseAddr + me32.modBaseSize) {
 657             (*close_snap) (hModuleSnap);
 658             FreeLibrary(dll);
 659 # ifdef _WIN32_WCE
 660 #  if _WIN32_WCE >= 101
 661             return WideCharToMultiByte(CP_ACP, 0, me32.szExePath, -1,
 662                                        path, sz, NULL, NULL);
 663 #  else
 664             {
 665                 int i, len = (int)wcslen(me32.szExePath);
 666                 if (sz <= 0)
 667                     return len + 1;
 668                 if (len >= sz)
 669                     len = sz - 1;
 670                 for (i = 0; i < len; i++)
 671                     path[i] = (char)me32.szExePath[i];
 672                 path[len++] = 0;
 673                 return len;
 674             }
 675 #  endif
 676 # else
 677             {
 678                 int len = (int)strlen(me32.szExePath);
 679                 if (sz <= 0)
 680                     return len + 1;
 681                 if (len >= sz)
 682                     len = sz - 1;
 683                 memcpy(path, me32.szExePath, len);
 684                 path[len++] = 0;
 685                 return len;
 686             }
 687 # endif
 688         }
 689     } while ((*module_next) (hModuleSnap, &me32));
 690
 691     (*close_snap) (hModuleSnap);
 692     FreeLibrary(dll);
 693     return 0;
 694 }
 695
 696 static void *win32_globallookup(const char *name)
 697 {
 698     HMODULE dll;
 699     HANDLE hModuleSnap = INVALID_HANDLE_VALUE;
 700     MODULEENTRY32 me32;
 701     CREATETOOLHELP32SNAPSHOT create_snap;
 702     CLOSETOOLHELP32SNAPSHOT close_snap;
 703     MODULE32 module_first, module_next;
 704     union {
 705         void *p;
 706         FARPROC f;
 707     } ret = { NULL };
 708
 709     dll = LoadLibrary(TEXT(DLLNAME));
 710     if (dll == NULL) {
 711         DSOerr(DSO_F_WIN32_GLOBALLOOKUP, DSO_R_UNSUPPORTED);
 712         return NULL;
 713     }
 714
 715     create_snap = (CREATETOOLHELP32SNAPSHOT)
 716         GetProcAddress(dll, "CreateToolhelp32Snapshot");
 717     if (create_snap == NULL) {
 718         FreeLibrary(dll);
 719         DSOerr(DSO_F_WIN32_GLOBALLOOKUP, DSO_R_UNSUPPORTED);
 720         return NULL;
 721     }
 722     /* We take the rest for granted... */
 723 # ifdef _WIN32_WCE
 724     close_snap = (CLOSETOOLHELP32SNAPSHOT)
 725         GetProcAddress(dll, "CloseToolhelp32Snapshot");
 726 # else
 727     close_snap = (CLOSETOOLHELP32SNAPSHOT) CloseHandle;
 728 # endif
 729     module_first = (MODULE32) GetProcAddress(dll, "Module32First");
 730     module_next = (MODULE32) GetProcAddress(dll, "Module32Next");
 731
 732     hModuleSnap = (*create_snap) (TH32CS_SNAPMODULE, 0);
 733     if (hModuleSnap == INVALID_HANDLE_VALUE) {
 734         FreeLibrary(dll);
 735         DSOerr(DSO_F_WIN32_GLOBALLOOKUP, DSO_R_UNSUPPORTED);
 736         return NULL;
 737     }
 738
 739     me32.dwSize = sizeof(me32);
 740
 741     if (!(*module_first) (hModuleSnap, &me32)) {
 742         (*close_snap) (hModuleSnap);
 743         FreeLibrary(dll);
 744         return NULL;
 745     }
 746
 747     do {
 748         if ((ret.f = GetProcAddress(me32.hModule, name))) {
 749             (*close_snap) (hModuleSnap);
 750             FreeLibrary(dll);
 751             return ret.p;
 752         }
 753     } while ((*module_next) (hModuleSnap, &me32));
 754
 755     (*close_snap) (hModuleSnap);
 756     FreeLibrary(dll);
 757     return NULL;
 758 }
 759 #endif                          /* DSO_WIN32 */