libs/wine/loader.c

   1 /*
   2  * Win32 builtin dlls support
   3  *
   4  * Copyright 2000 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include "config.h"
  22 #include "wine/port.h"
  23
  24 #include <assert.h>
  25 #include <ctype.h>
  26 #include <fcntl.h>
  27 #include <stdarg.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <sys/types.h>
  31 #ifdef HAVE_SYS_MMAN_H
  32 #include <sys/mman.h>
  33 #endif
  34 #ifdef HAVE_UNISTD_H
  35 # include <unistd.h>
  36 #endif
  37
  38 #define NONAMELESSUNION
  39 #define NONAMELESSSTRUCT
  40 #include "windef.h"
  41 #include "winbase.h"
  42 #include "wine/library.h"
  43
  44 #ifdef __APPLE__
  45 #include <crt_externs.h>
  46 #define environ (*_NSGetEnviron())
  47 #else
  48 extern char **environ;
  49 #endif
  50
  51 /* argc/argv for the Windows application */
  52 int __wine_main_argc = 0;
  53 char **__wine_main_argv = NULL;
  54 WCHAR **__wine_main_wargv = NULL;
  55 char **__wine_main_environ = NULL;
  56
  57 struct dll_path_context
  58 {
  59     int   index;    /* current index in the dll path list */
  60     char *buffer;   /* buffer used for storing path names */
  61     char *name;     /* start of file name part in buffer (including leading slash) */
  62     int   namelen;  /* length of file name without .so extension */
  63 };
  64
  65 #define MAX_DLLS 100
  66
  67 static struct
  68 {
  69     const IMAGE_NT_HEADERS *nt;           /* NT header */
  70     const char             *filename;     /* DLL file name */
  71 } builtin_dlls[MAX_DLLS];
  72
  73 static int nb_dlls;
  74
  75 static const IMAGE_NT_HEADERS *main_exe;
  76
  77 static load_dll_callback_t load_dll_callback;
  78
  79 static const char *build_dir;
  80 static const char *default_dlldir;
  81 static const char **dll_paths;
  82 static int nb_dll_paths;
  83 static int dll_path_maxlen;
  84
  85 extern void mmap_init(void);
  86 extern void debug_init(void);
  87 extern const char *get_dlldir( const char **default_dlldir );
  88
  89 /* build the dll load path from the WINEDLLPATH variable */
  90 static void build_dll_path(void)
  91 {
  92     int len, count = 0;
  93     char *p, *path = getenv( "WINEDLLPATH" );
  94     const char *dlldir = get_dlldir( &default_dlldir );
  95
  96     if (path)
  97     {
  98         /* count how many path elements we need */
  99         path = strdup(path);
 100         p = path;
 101         while (*p)
 102         {
 103             while (*p == ':') p++;
 104             if (!*p) break;
 105             count++;
 106             while (*p && *p != ':') p++;
 107         }
 108     }
 109
 110     dll_paths = malloc( (count+2) * sizeof(*dll_paths) );
 111     nb_dll_paths = 0;
 112
 113     if (dlldir)
 114     {
 115         dll_path_maxlen = strlen(dlldir);
 116         dll_paths[nb_dll_paths++] = dlldir;
 117     }
 118     else if ((build_dir = wine_get_build_dir()))
 119     {
 120         dll_path_maxlen = strlen(build_dir) + sizeof("/programs");
 121     }
 122
 123     if (count)
 124     {
 125         p = path;
 126         while (*p)
 127         {
 128             while (*p == ':') *p++ = 0;
 129             if (!*p) break;
 130             dll_paths[nb_dll_paths] = p;
 131             while (*p && *p != ':') p++;
 132             if (p - dll_paths[nb_dll_paths] > dll_path_maxlen)
 133                 dll_path_maxlen = p - dll_paths[nb_dll_paths];
 134             nb_dll_paths++;
 135         }
 136     }
 137
 138     /* append default dll dir (if not empty) to path */
 139     if ((len = strlen(default_dlldir)) > 0)
 140     {
 141         if (len > dll_path_maxlen) dll_path_maxlen = len;
 142         dll_paths[nb_dll_paths++] = default_dlldir;
 143     }
 144 }
 145
 146 /* check if a given file can be opened */
 147 inline static int file_exists( const char *name )
 148 {
 149     int fd = open( name, O_RDONLY );
 150     if (fd != -1) close( fd );
 151     return (fd != -1);
 152 }
 153
 154 inline static char *prepend( char *buffer, const char *str, size_t len )
 155 {
 156     return memcpy( buffer - len, str, len );
 157 }
 158
 159 /* get a filename from the next entry in the dll path */
 160 static char *next_dll_path( struct dll_path_context *context )
 161 {
 162     int index = context->index++;
 163     int namelen = context->namelen;
 164     char *path = context->name;
 165
 166     switch(index)
 167     {
 168     case 0:  /* try programs dir for .exe files */
 169         if (namelen > 4 && !memcmp( context->name + namelen - 4, ".exe", 4 ))
 170         {
 171             path = prepend( path, context->name, namelen - 4 );
 172             path = prepend( path, "/programs", sizeof("/programs") - 1 );
 173             path = prepend( path, build_dir, strlen(build_dir) );
 174             return path;
 175         }
 176         context->index++;
 177         /* fall through */
 178     case 1:  /* try dlls dir with subdir prefix */
 179         if (namelen > 4 && !memcmp( context->name + namelen - 4, ".dll", 4 )) namelen -= 4;
 180         path = prepend( path, context->name, namelen );
 181         /* fall through */
 182     case 2:  /* try dlls dir without prefix */
 183         path = prepend( path, "/dlls", sizeof("/dlls") - 1 );
 184         path = prepend( path, build_dir, strlen(build_dir) );
 185         return path;
 186     default:
 187         index -= 3;
 188         if (index < nb_dll_paths)
 189             return prepend( context->name, dll_paths[index], strlen( dll_paths[index] ));
 190         break;
 191     }
 192     return NULL;
 193 }
 194
 195
 196 /* get a filename from the first entry in the dll path */
 197 static char *first_dll_path( const char *name, const char *ext, struct dll_path_context *context )
 198 {
 199     char *p;
 200     int namelen = strlen( name );
 201
 202     context->buffer = malloc( dll_path_maxlen + 2 * namelen + strlen(ext) + 3 );
 203     context->index = build_dir ? 0 : 3;  /* if no build dir skip all the build dir magic cases */
 204     context->name = context->buffer + dll_path_maxlen + namelen + 1;
 205     context->namelen = namelen + 1;
 206
 207     /* store the name at the end of the buffer, followed by extension */
 208     p = context->name;
 209     *p++ = '/';
 210     memcpy( p, name, namelen );
 211     strcpy( p + namelen, ext );
 212     return next_dll_path( context );
 213 }
 214
 215
 216 /* free the dll path context created by first_dll_path */
 217 inline static void free_dll_path( struct dll_path_context *context )
 218 {
 219     free( context->buffer );
 220 }
 221
 222
 223 /* open a library for a given dll, searching in the dll path
 224  * 'name' must be the Windows dll name (e.g. "kernel32.dll") */
 225 static void *dlopen_dll( const char *name, char *error, int errorsize,
 226                          int test_only, int *exists )
 227 {
 228     struct dll_path_context context;
 229     char *path;
 230     void *ret = NULL;
 231
 232     *exists = 0;
 233     for (path = first_dll_path( name, ".so", &context ); path; path = next_dll_path( &context ))
 234     {
 235         if (!test_only && (ret = wine_dlopen( path, RTLD_NOW, error, errorsize ))) break;
 236         if ((*exists = file_exists( path ))) break; /* exists but cannot be loaded, return the error */
 237     }
 238     free_dll_path( &context );
 239     return ret;
 240 }
 241
 242
 243 /* adjust an array of pointers to make them into RVAs */
 244 static inline void fixup_rva_ptrs( void *array, BYTE *base, unsigned int count )
 245 {
 246     void **src = (void **)array;
 247     DWORD *dst = (DWORD *)array;
 248     while (count--)
 249     {
 250         *dst++ = *src ? (BYTE *)*src - base : 0;
 251         src++;
 252     }
 253 }
 254
 255 /* fixup an array of RVAs by adding the specified delta */
 256 static inline void fixup_rva_dwords( DWORD *ptr, int delta, unsigned int count )
 257 {
 258     while (count--)
 259     {
 260         if (*ptr) *ptr += delta;
 261         ptr++;
 262     }
 263 }
 264
 265
 266 /* fixup RVAs in the import directory */
 267 static void fixup_imports( IMAGE_IMPORT_DESCRIPTOR *dir, BYTE *base, int delta )
 268 {
 269     UINT_PTR *ptr;
 270
 271     while (dir->Name)
 272     {
 273         fixup_rva_dwords( &dir->u.OriginalFirstThunk, delta, 1 );
 274         fixup_rva_dwords( &dir->Name, delta, 1 );
 275         fixup_rva_dwords( &dir->FirstThunk, delta, 1 );
 276         ptr = (UINT_PTR *)(base + dir->FirstThunk);
 277         while (*ptr)
 278         {
 279             if (!(*ptr & IMAGE_ORDINAL_FLAG)) *ptr += delta;
 280             ptr++;
 281         }
 282         dir++;
 283     }
 284 }
 285
 286
 287 /* fixup RVAs in the export directory */
 288 static void fixup_exports( IMAGE_EXPORT_DIRECTORY *dir, BYTE *base, int delta )
 289 {
 290     fixup_rva_dwords( &dir->Name, delta, 1 );
 291     fixup_rva_dwords( &dir->AddressOfFunctions, delta, 1 );
 292     fixup_rva_dwords( &dir->AddressOfNames, delta, 1 );
 293     fixup_rva_dwords( &dir->AddressOfNameOrdinals, delta, 1 );
 294     fixup_rva_dwords( (DWORD *)(base + dir->AddressOfNames), delta, dir->NumberOfNames );
 295     fixup_rva_ptrs( (base + dir->AddressOfFunctions), base, dir->NumberOfFunctions );
 296 }
 297
 298
 299 /* fixup RVAs in the resource directory */
 300 static void fixup_resources( IMAGE_RESOURCE_DIRECTORY *dir, BYTE *root, int delta )
 301 {
 302     IMAGE_RESOURCE_DIRECTORY_ENTRY *entry;
 303     int i;
 304
 305     entry = (IMAGE_RESOURCE_DIRECTORY_ENTRY *)(dir + 1);
 306     for (i = 0; i < dir->NumberOfNamedEntries + dir->NumberOfIdEntries; i++, entry++)
 307     {
 308         void *ptr = root + entry->u2.s3.OffsetToDirectory;
 309         if (entry->u2.s3.DataIsDirectory) fixup_resources( ptr, root, delta );
 310         else
 311         {
 312             IMAGE_RESOURCE_DATA_ENTRY *data = ptr;
 313             fixup_rva_dwords( &data->OffsetToData, delta, 1 );
 314         }
 315     }
 316 }
 317
 318
 319 /* map a builtin dll in memory and fixup RVAs */
 320 static void *map_dll( const IMAGE_NT_HEADERS *nt_descr )
 321 {
 322 #ifdef HAVE_MMAP
 323     IMAGE_DATA_DIRECTORY *dir;
 324     IMAGE_DOS_HEADER *dos;
 325     IMAGE_NT_HEADERS *nt;
 326     IMAGE_SECTION_HEADER *sec;
 327     BYTE *addr;
 328     DWORD code_start, data_start, data_end;
 329     const size_t page_size = getpagesize();
 330     const size_t page_mask = page_size - 1;
 331     int i, delta, nb_sections = 2;  /* code + data */
 332
 333     size_t size = (sizeof(IMAGE_DOS_HEADER)
 334                    + sizeof(IMAGE_NT_HEADERS)
 335                    + nb_sections * sizeof(IMAGE_SECTION_HEADER));
 336
 337     assert( size <= page_size );
 338
 339     /* module address must be aligned on 64K boundary */
 340     addr = (BYTE *)((nt_descr->OptionalHeader.ImageBase + 0xffff) & ~0xffff);
 341     if (wine_anon_mmap( addr, page_size, PROT_READ|PROT_WRITE, MAP_FIXED ) != addr) return NULL;
 342
 343     dos    = (IMAGE_DOS_HEADER *)addr;
 344     nt     = (IMAGE_NT_HEADERS *)(dos + 1);
 345     sec    = (IMAGE_SECTION_HEADER *)(nt + 1);
 346
 347     /* Build the DOS and NT headers */
 348
 349     dos->e_magic    = IMAGE_DOS_SIGNATURE;
 350     dos->e_cblp     = sizeof(*dos);
 351     dos->e_cp       = 1;
 352     dos->e_cparhdr  = (sizeof(*dos)+0xf)/0x10;
 353     dos->e_minalloc = 0;
 354     dos->e_maxalloc = 0xffff;
 355     dos->e_ss       = 0x0000;
 356     dos->e_sp       = 0x00b8;
 357     dos->e_lfarlc   = sizeof(*dos);
 358     dos->e_lfanew   = sizeof(*dos);
 359
 360     *nt = *nt_descr;
 361
 362     delta      = (BYTE *)nt_descr - addr;
 363     code_start = page_size;
 364     data_start = delta & ~page_mask;
 365     data_end   = (nt->OptionalHeader.SizeOfImage + delta + page_mask) & ~page_mask;
 366
 367     fixup_rva_ptrs( &nt->OptionalHeader.AddressOfEntryPoint, addr, 1 );
 368
 369     nt->FileHeader.NumberOfSections                = nb_sections;
 370     nt->OptionalHeader.BaseOfCode                  = code_start;
 371 #ifndef _WIN64
 372     nt->OptionalHeader.BaseOfData                  = data_start;
 373 #endif
 374     nt->OptionalHeader.SizeOfCode                  = data_start - code_start;
 375     nt->OptionalHeader.SizeOfInitializedData       = data_end - data_start;
 376     nt->OptionalHeader.SizeOfUninitializedData     = 0;
 377     nt->OptionalHeader.SizeOfImage                 = data_end;
 378     nt->OptionalHeader.ImageBase                   = (ULONG_PTR)addr;
 379
 380     /* Build the code section */
 381
 382     memcpy( sec->Name, ".text", sizeof(".text") );
 383     sec->SizeOfRawData = data_start - code_start;
 384     sec->Misc.VirtualSize = sec->SizeOfRawData;
 385     sec->VirtualAddress   = code_start;
 386     sec->PointerToRawData = code_start;
 387     sec->Characteristics  = (IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ);
 388     sec++;
 389
 390     /* Build the data section */
 391
 392     memcpy( sec->Name, ".data", sizeof(".data") );
 393     sec->SizeOfRawData = data_end - data_start;
 394     sec->Misc.VirtualSize = sec->SizeOfRawData;
 395     sec->VirtualAddress   = data_start;
 396     sec->PointerToRawData = data_start;
 397     sec->Characteristics  = (IMAGE_SCN_CNT_INITIALIZED_DATA |
 398                              IMAGE_SCN_MEM_WRITE | IMAGE_SCN_MEM_READ);
 399     sec++;
 400
 401     for (i = 0; i < nt->OptionalHeader.NumberOfRvaAndSizes; i++)
 402         fixup_rva_dwords( &nt->OptionalHeader.DataDirectory[i].VirtualAddress, delta, 1 );
 403
 404     /* Build the import directory */
 405
 406     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_IMPORT_DIRECTORY];
 407     if (dir->Size)
 408     {
 409         IMAGE_IMPORT_DESCRIPTOR *imports = (void *)(addr + dir->VirtualAddress);
 410         fixup_imports( imports, addr, delta );
 411     }
 412
 413     /* Build the resource directory */
 414
 415     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_RESOURCE_DIRECTORY];
 416     if (dir->Size)
 417     {
 418         void *ptr = (void *)(addr + dir->VirtualAddress);
 419         fixup_resources( ptr, ptr, delta );
 420     }
 421
 422     /* Build the export directory */
 423
 424     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_EXPORT_DIRECTORY];
 425     if (dir->Size)
 426     {
 427         IMAGE_EXPORT_DIRECTORY *exports = (void *)(addr + dir->VirtualAddress);
 428         fixup_exports( exports, addr, delta );
 429     }
 430     return addr;
 431 #else  /* HAVE_MMAP */
 432     return NULL;
 433 #endif  /* HAVE_MMAP */
 434 }
 435
 436
 437 /***********************************************************************
 438  *           __wine_dll_register
 439  *
 440  * Register a built-in DLL descriptor.
 441  */
 442 void __wine_dll_register( const IMAGE_NT_HEADERS *header, const char *filename )
 443 {
 444     if (load_dll_callback) load_dll_callback( map_dll(header), filename );
 445     else
 446     {
 447         if (!(header->FileHeader.Characteristics & IMAGE_FILE_DLL))
 448             main_exe = header;
 449         else
 450         {
 451             assert( nb_dlls < MAX_DLLS );
 452             builtin_dlls[nb_dlls].nt = header;
 453             builtin_dlls[nb_dlls].filename = filename;
 454             nb_dlls++;
 455         }
 456     }
 457 }
 458
 459
 460 /***********************************************************************
 461  *           wine_dll_set_callback
 462  *
 463  * Set the callback function for dll loading, and call it
 464  * for all dlls that were implicitly loaded already.
 465  */
 466 void wine_dll_set_callback( load_dll_callback_t load )
 467 {
 468     int i;
 469     load_dll_callback = load;
 470     for (i = 0; i < nb_dlls; i++)
 471     {
 472         const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 473         if (!nt) continue;
 474         builtin_dlls[i].nt = NULL;
 475         load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 476     }
 477     nb_dlls = 0;
 478     if (main_exe) load_dll_callback( map_dll(main_exe), "" );
 479 }
 480
 481
 482 /***********************************************************************
 483  *           wine_dll_load
 484  *
 485  * Load a builtin dll.
 486  */
 487 void *wine_dll_load( const char *filename, char *error, int errorsize, int *file_exists )
 488 {
 489     int i;
 490
 491     /* callback must have been set already */
 492     assert( load_dll_callback );
 493
 494     /* check if we have it in the list */
 495     /* this can happen when initializing pre-loaded dlls in wine_dll_set_callback */
 496     for (i = 0; i < nb_dlls; i++)
 497     {
 498         if (!builtin_dlls[i].nt) continue;
 499         if (!strcmp( builtin_dlls[i].filename, filename ))
 500         {
 501             const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 502             builtin_dlls[i].nt = NULL;
 503             load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 504             *file_exists = 1;
 505             return (void *)1;
 506         }
 507     }
 508     return dlopen_dll( filename, error, errorsize, 0, file_exists );
 509 }
 510
 511
 512 /***********************************************************************
 513  *           wine_dll_unload
 514  *
 515  * Unload a builtin dll.
 516  */
 517 void wine_dll_unload( void *handle )
 518 {
 519     if (handle != (void *)1)
 520         wine_dlclose( handle, NULL, 0 );
 521 }
 522
 523
 524 /***********************************************************************
 525  *           wine_dll_load_main_exe
 526  *
 527  * Try to load the .so for the main exe.
 528  */
 529 void *wine_dll_load_main_exe( const char *name, char *error, int errorsize,
 530                               int test_only, int *file_exists )
 531 {
 532     return dlopen_dll( name, error, errorsize, test_only, file_exists );
 533 }
 534
 535
 536 /***********************************************************************
 537  *           wine_dll_enum_load_path
 538  *
 539  * Enumerate the dll load path.
 540  */
 541 const char *wine_dll_enum_load_path( unsigned int index )
 542 {
 543     if (index >= nb_dll_paths) return NULL;
 544     return dll_paths[index];
 545 }
 546
 547
 548 /***********************************************************************
 549  *           wine_dll_get_owner
 550  *
 551  * Retrieve the name of the 32-bit owner dll for a 16-bit dll.
 552  * Return 0 if OK, -1 on error.
 553  */
 554 int wine_dll_get_owner( const char *name, char *buffer, int size, int *exists )
 555 {
 556     int ret = -1;
 557     char *path;
 558     struct dll_path_context context;
 559
 560     *exists = 0;
 561
 562     for (path = first_dll_path( name, "16", &context ); path; path = next_dll_path( &context ))
 563     {
 564         int fd = open( path, O_RDONLY );
 565         if (fd != -1)
 566         {
 567             int res = read( fd, buffer, size - 1 );
 568             while (res > 0 && (buffer[res-1] == '\n' || buffer[res-1] == '\r')) res--;
 569             buffer[res] = 0;
 570             close( fd );
 571             *exists = 1;
 572             ret = 0;
 573             break;
 574         }
 575     }
 576     free_dll_path( &context );
 577     if (ret != -1) return ret;
 578
 579     /* try old method too for backwards compatibility; will be removed later on */
 580     for (path = first_dll_path( name, ".so", &context ); path; path = next_dll_path( &context ))
 581     {
 582         int res = readlink( path, buffer, size );
 583         if (res != -1) /* got a symlink */
 584         {
 585             *exists = 1;
 586             if (res < 4 || res >= size) break;
 587             buffer[res] = 0;
 588             if (strchr( buffer, '/' )) break;  /* contains a path, not valid */
 589             if (strcmp( buffer + res - 3, ".so" )) break;  /* does not end in .so, not valid */
 590             buffer[res - 3] = 0;  /* remove .so */
 591             ret = 0;
 592             break;
 593         }
 594         if ((*exists = file_exists( path ))) break; /* exists but not a symlink, return the error */
 595     }
 596     free_dll_path( &context );
 597     return ret;
 598 }
 599
 600
 601 /***********************************************************************
 602  *           wine_init
 603  *
 604  * Main Wine initialisation.
 605  */
 606 void wine_init( int argc, char *argv[], char *error, int error_size )
 607 {
 608     struct dll_path_context context;
 609     char *path;
 610     void *ntdll = NULL;
 611     void (*init_func)(void);
 612
 613     wine_init_argv0_path( argv[0] );
 614     build_dll_path();
 615     __wine_main_argc = argc;
 616     __wine_main_argv = argv;
 617     __wine_main_environ = environ;
 618     mmap_init();
 619     debug_init();
 620
 621     for (path = first_dll_path( "ntdll.dll", ".so", &context ); path; path = next_dll_path( &context ))
 622     {
 623         if ((ntdll = wine_dlopen( path, RTLD_NOW, error, error_size )))
 624         {
 625             /* if we didn't use the default dll dir, remove it from the search path */
 626             if (default_dlldir[0] && context.index < nb_dll_paths) nb_dll_paths--;
 627             break;
 628         }
 629     }
 630     free_dll_path( &context );
 631
 632     if (!ntdll) return;
 633     if (!(init_func = wine_dlsym( ntdll, "__wine_process_init", error, error_size ))) return;
 634     init_func();
 635 }
 636
 637
 638 /*
 639  * These functions provide wrappers around dlopen() and associated
 640  * functions.  They work around a bug in glibc 2.1.x where calling
 641  * a dl*() function after a previous dl*() function has failed
 642  * without a dlerror() call between the two will cause a crash.
 643  * They all take a pointer to a buffer that
 644  * will receive the error description (from dlerror()).  This
 645  * parameter may be NULL if the error description is not required.
 646  */
 647
 648 #ifndef RTLD_FIRST
 649 #define RTLD_FIRST 0
 650 #endif
 651
 652 /***********************************************************************
 653  *              wine_dlopen
 654  */
 655 void *wine_dlopen( const char *filename, int flag, char *error, size_t errorsize )
 656 {
 657 #ifdef HAVE_DLOPEN
 658     void *ret;
 659     const char *s;
 660     dlerror(); dlerror();
 661     ret = dlopen( filename, flag | RTLD_FIRST );
 662     s = dlerror();
 663     if (error && errorsize)
 664     {
 665         if (s)
 666         {
 667             size_t len = strlen(s);
 668             if (len >= errorsize) len = errorsize - 1;
 669             memcpy( error, s, len );
 670             error[len] = 0;
 671         }
 672         else error[0] = 0;
 673     }
 674     dlerror();
 675     return ret;
 676 #else
 677     if (error)
 678     {
 679         static const char msg[] = "dlopen interface not detected by configure";
 680         size_t len = min( errorsize, sizeof(msg) );
 681         memcpy( error, msg, len );
 682         error[len - 1] = 0;
 683     }
 684     return NULL;
 685 #endif
 686 }
 687
 688 /***********************************************************************
 689  *              wine_dlsym
 690  */
 691 void *wine_dlsym( void *handle, const char *symbol, char *error, size_t errorsize )
 692 {
 693 #ifdef HAVE_DLOPEN
 694     void *ret;
 695     const char *s;
 696     dlerror(); dlerror();
 697     ret = dlsym( handle, symbol );
 698     s = dlerror();
 699     if (error && errorsize)
 700     {
 701         if (s)
 702         {
 703             size_t len = strlen(s);
 704             if (len >= errorsize) len = errorsize - 1;
 705             memcpy( error, s, len );
 706             error[len] = 0;
 707         }
 708         else error[0] = 0;
 709     }
 710     dlerror();
 711     return ret;
 712 #else
 713     if (error)
 714     {
 715         static const char msg[] = "dlopen interface not detected by configure";
 716         size_t len = min( errorsize, sizeof(msg) );
 717         memcpy( error, msg, len );
 718         error[len - 1] = 0;
 719     }
 720     return NULL;
 721 #endif
 722 }
 723
 724 /***********************************************************************
 725  *              wine_dlclose
 726  */
 727 int wine_dlclose( void *handle, char *error, size_t errorsize )
 728 {
 729 #ifdef HAVE_DLOPEN
 730     int ret;
 731     const char *s;
 732     dlerror(); dlerror();
 733     ret = dlclose( handle );
 734     s = dlerror();
 735     if (error && errorsize)
 736     {
 737         if (s)
 738         {
 739             size_t len = strlen(s);
 740             if (len >= errorsize) len = errorsize - 1;
 741             memcpy( error, s, len );
 742             error[len] = 0;
 743         }
 744         else error[0] = 0;
 745     }
 746     dlerror();
 747     return ret;
 748 #else
 749     if (error)
 750     {
 751         static const char msg[] = "dlopen interface not detected by configure";
 752         size_t len = min( errorsize, sizeof(msg) );
 753         memcpy( error, msg, len );
 754         error[len - 1] = 0;
 755     }
 756     return 1;
 757 #endif
 758 }