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_SYS_RESOURCE_H
  35 # include <sys/resource.h>
  36 #endif
  37 #ifdef HAVE_UNISTD_H
  38 # include <unistd.h>
  39 #endif
  40
  41 #define NONAMELESSUNION
  42 #define NONAMELESSSTRUCT
  43 #include "windef.h"
  44 #include "winbase.h"
  45 #include "wine/library.h"
  46
  47 #ifdef __APPLE__
  48 #include <crt_externs.h>
  49 #define environ (*_NSGetEnviron())
  50 #else
  51 extern char **environ;
  52 #endif
  53
  54 /* argc/argv for the Windows application */
  55 int __wine_main_argc = 0;
  56 char **__wine_main_argv = NULL;
  57 WCHAR **__wine_main_wargv = NULL;
  58 char **__wine_main_environ = NULL;
  59
  60 struct dll_path_context
  61 {
  62     int   index;    /* current index in the dll path list */
  63     char *buffer;   /* buffer used for storing path names */
  64     char *name;     /* start of file name part in buffer (including leading slash) */
  65     int   namelen;  /* length of file name without .so extension */
  66 };
  67
  68 #define MAX_DLLS 100
  69
  70 static struct
  71 {
  72     const IMAGE_NT_HEADERS *nt;           /* NT header */
  73     const char             *filename;     /* DLL file name */
  74 } builtin_dlls[MAX_DLLS];
  75
  76 static int nb_dlls;
  77
  78 static const IMAGE_NT_HEADERS *main_exe;
  79
  80 static load_dll_callback_t load_dll_callback;
  81
  82 static const char *build_dir;
  83 static const char *default_dlldir;
  84 static const char **dll_paths;
  85 static int nb_dll_paths;
  86 static int dll_path_maxlen;
  87
  88 extern void mmap_init(void);
  89 extern void debug_init(void);
  90 extern const char *get_dlldir( const char **default_dlldir );
  91
  92 /* build the dll load path from the WINEDLLPATH variable */
  93 static void build_dll_path(void)
  94 {
  95     int len, count = 0;
  96     char *p, *path = getenv( "WINEDLLPATH" );
  97     const char *dlldir = get_dlldir( &default_dlldir );
  98
  99     if (path)
 100     {
 101         /* count how many path elements we need */
 102         path = strdup(path);
 103         p = path;
 104         while (*p)
 105         {
 106             while (*p == ':') p++;
 107             if (!*p) break;
 108             count++;
 109             while (*p && *p != ':') p++;
 110         }
 111     }
 112
 113     dll_paths = malloc( (count+2) * sizeof(*dll_paths) );
 114     nb_dll_paths = 0;
 115
 116     if (dlldir)
 117     {
 118         dll_path_maxlen = strlen(dlldir);
 119         dll_paths[nb_dll_paths++] = dlldir;
 120     }
 121     else if ((build_dir = wine_get_build_dir()))
 122     {
 123         dll_path_maxlen = strlen(build_dir) + sizeof("/programs");
 124     }
 125
 126     if (count)
 127     {
 128         p = path;
 129         while (*p)
 130         {
 131             while (*p == ':') *p++ = 0;
 132             if (!*p) break;
 133             dll_paths[nb_dll_paths] = p;
 134             while (*p && *p != ':') p++;
 135             if (p - dll_paths[nb_dll_paths] > dll_path_maxlen)
 136                 dll_path_maxlen = p - dll_paths[nb_dll_paths];
 137             nb_dll_paths++;
 138         }
 139     }
 140
 141     /* append default dll dir (if not empty) to path */
 142     if ((len = strlen(default_dlldir)) > 0)
 143     {
 144         if (len > dll_path_maxlen) dll_path_maxlen = len;
 145         dll_paths[nb_dll_paths++] = default_dlldir;
 146     }
 147 }
 148
 149 /* check if a given file can be opened */
 150 inline static int file_exists( const char *name )
 151 {
 152     int fd = open( name, O_RDONLY );
 153     if (fd != -1) close( fd );
 154     return (fd != -1);
 155 }
 156
 157 inline static char *prepend( char *buffer, const char *str, size_t len )
 158 {
 159     return memcpy( buffer - len, str, len );
 160 }
 161
 162 /* get a filename from the next entry in the dll path */
 163 static char *next_dll_path( struct dll_path_context *context )
 164 {
 165     int index = context->index++;
 166     int namelen = context->namelen;
 167     char *path = context->name;
 168
 169     switch(index)
 170     {
 171     case 0:  /* try programs dir for .exe files */
 172         if (namelen > 4 && !memcmp( context->name + namelen - 4, ".exe", 4 ))
 173         {
 174             path = prepend( path, context->name, namelen - 4 );
 175             path = prepend( path, "/programs", sizeof("/programs") - 1 );
 176             path = prepend( path, build_dir, strlen(build_dir) );
 177             return path;
 178         }
 179         context->index++;
 180         /* fall through */
 181     case 1:  /* try dlls dir with subdir prefix */
 182         if (namelen > 4 && !memcmp( context->name + namelen - 4, ".dll", 4 )) namelen -= 4;
 183         path = prepend( path, context->name, namelen );
 184         /* fall through */
 185     case 2:  /* try dlls dir without prefix */
 186         path = prepend( path, "/dlls", sizeof("/dlls") - 1 );
 187         path = prepend( path, build_dir, strlen(build_dir) );
 188         return path;
 189     default:
 190         index -= 3;
 191         if (index < nb_dll_paths)
 192             return prepend( context->name, dll_paths[index], strlen( dll_paths[index] ));
 193         break;
 194     }
 195     return NULL;
 196 }
 197
 198
 199 /* get a filename from the first entry in the dll path */
 200 static char *first_dll_path( const char *name, const char *ext, struct dll_path_context *context )
 201 {
 202     char *p;
 203     int namelen = strlen( name );
 204
 205     context->buffer = malloc( dll_path_maxlen + 2 * namelen + strlen(ext) + 3 );
 206     context->index = build_dir ? 0 : 3;  /* if no build dir skip all the build dir magic cases */
 207     context->name = context->buffer + dll_path_maxlen + namelen + 1;
 208     context->namelen = namelen + 1;
 209
 210     /* store the name at the end of the buffer, followed by extension */
 211     p = context->name;
 212     *p++ = '/';
 213     memcpy( p, name, namelen );
 214     strcpy( p + namelen, ext );
 215     return next_dll_path( context );
 216 }
 217
 218
 219 /* free the dll path context created by first_dll_path */
 220 inline static void free_dll_path( struct dll_path_context *context )
 221 {
 222     free( context->buffer );
 223 }
 224
 225
 226 /* open a library for a given dll, searching in the dll path
 227  * 'name' must be the Windows dll name (e.g. "kernel32.dll") */
 228 static void *dlopen_dll( const char *name, char *error, int errorsize,
 229                          int test_only, int *exists )
 230 {
 231     struct dll_path_context context;
 232     char *path;
 233     void *ret = NULL;
 234
 235     *exists = 0;
 236     for (path = first_dll_path( name, ".so", &context ); path; path = next_dll_path( &context ))
 237     {
 238         if (!test_only && (ret = wine_dlopen( path, RTLD_NOW, error, errorsize ))) break;
 239         if ((*exists = file_exists( path ))) break; /* exists but cannot be loaded, return the error */
 240     }
 241     free_dll_path( &context );
 242     return ret;
 243 }
 244
 245
 246 /* adjust an array of pointers to make them into RVAs */
 247 static inline void fixup_rva_ptrs( void *array, BYTE *base, unsigned int count )
 248 {
 249     void **src = (void **)array;
 250     DWORD *dst = (DWORD *)array;
 251     while (count--)
 252     {
 253         *dst++ = *src ? (BYTE *)*src - base : 0;
 254         src++;
 255     }
 256 }
 257
 258 /* fixup an array of RVAs by adding the specified delta */
 259 static inline void fixup_rva_dwords( DWORD *ptr, int delta, unsigned int count )
 260 {
 261     while (count--)
 262     {
 263         if (*ptr) *ptr += delta;
 264         ptr++;
 265     }
 266 }
 267
 268
 269 /* fixup RVAs in the import directory */
 270 static void fixup_imports( IMAGE_IMPORT_DESCRIPTOR *dir, BYTE *base, int delta )
 271 {
 272     UINT_PTR *ptr;
 273
 274     while (dir->Name)
 275     {
 276         fixup_rva_dwords( &dir->u.OriginalFirstThunk, delta, 1 );
 277         fixup_rva_dwords( &dir->Name, delta, 1 );
 278         fixup_rva_dwords( &dir->FirstThunk, delta, 1 );
 279         ptr = (UINT_PTR *)(base + dir->FirstThunk);
 280         while (*ptr)
 281         {
 282             if (!(*ptr & IMAGE_ORDINAL_FLAG)) *ptr += delta;
 283             ptr++;
 284         }
 285         dir++;
 286     }
 287 }
 288
 289
 290 /* fixup RVAs in the export directory */
 291 static void fixup_exports( IMAGE_EXPORT_DIRECTORY *dir, BYTE *base, int delta )
 292 {
 293     fixup_rva_dwords( &dir->Name, delta, 1 );
 294     fixup_rva_dwords( &dir->AddressOfFunctions, delta, 1 );
 295     fixup_rva_dwords( &dir->AddressOfNames, delta, 1 );
 296     fixup_rva_dwords( &dir->AddressOfNameOrdinals, delta, 1 );
 297     fixup_rva_dwords( (DWORD *)(base + dir->AddressOfNames), delta, dir->NumberOfNames );
 298     fixup_rva_ptrs( (base + dir->AddressOfFunctions), base, dir->NumberOfFunctions );
 299 }
 300
 301
 302 /* fixup RVAs in the resource directory */
 303 static void fixup_resources( IMAGE_RESOURCE_DIRECTORY *dir, BYTE *root, int delta )
 304 {
 305     IMAGE_RESOURCE_DIRECTORY_ENTRY *entry;
 306     int i;
 307
 308     entry = (IMAGE_RESOURCE_DIRECTORY_ENTRY *)(dir + 1);
 309     for (i = 0; i < dir->NumberOfNamedEntries + dir->NumberOfIdEntries; i++, entry++)
 310     {
 311         void *ptr = root + entry->u2.s3.OffsetToDirectory;
 312         if (entry->u2.s3.DataIsDirectory) fixup_resources( ptr, root, delta );
 313         else
 314         {
 315             IMAGE_RESOURCE_DATA_ENTRY *data = ptr;
 316             fixup_rva_dwords( &data->OffsetToData, delta, 1 );
 317         }
 318     }
 319 }
 320
 321
 322 /* map a builtin dll in memory and fixup RVAs */
 323 static void *map_dll( const IMAGE_NT_HEADERS *nt_descr )
 324 {
 325 #ifdef HAVE_MMAP
 326     IMAGE_DATA_DIRECTORY *dir;
 327     IMAGE_DOS_HEADER *dos;
 328     IMAGE_NT_HEADERS *nt;
 329     IMAGE_SECTION_HEADER *sec;
 330     BYTE *addr;
 331     DWORD code_start, data_start, data_end;
 332     const size_t page_size = getpagesize();
 333     const size_t page_mask = page_size - 1;
 334     int i, delta, nb_sections = 2;  /* code + data */
 335
 336     size_t size = (sizeof(IMAGE_DOS_HEADER)
 337                    + sizeof(IMAGE_NT_HEADERS)
 338                    + nb_sections * sizeof(IMAGE_SECTION_HEADER));
 339
 340     assert( size <= page_size );
 341
 342     /* module address must be aligned on 64K boundary */
 343     addr = (BYTE *)((nt_descr->OptionalHeader.ImageBase + 0xffff) & ~0xffff);
 344     if (wine_anon_mmap( addr, page_size, PROT_READ|PROT_WRITE, MAP_FIXED ) != addr) return NULL;
 345
 346     dos    = (IMAGE_DOS_HEADER *)addr;
 347     nt     = (IMAGE_NT_HEADERS *)(dos + 1);
 348     sec    = (IMAGE_SECTION_HEADER *)(nt + 1);
 349
 350     /* Build the DOS and NT headers */
 351
 352     dos->e_magic    = IMAGE_DOS_SIGNATURE;
 353     dos->e_cblp     = sizeof(*dos);
 354     dos->e_cp       = 1;
 355     dos->e_cparhdr  = (sizeof(*dos)+0xf)/0x10;
 356     dos->e_minalloc = 0;
 357     dos->e_maxalloc = 0xffff;
 358     dos->e_ss       = 0x0000;
 359     dos->e_sp       = 0x00b8;
 360     dos->e_lfarlc   = sizeof(*dos);
 361     dos->e_lfanew   = sizeof(*dos);
 362
 363     *nt = *nt_descr;
 364
 365     delta      = (BYTE *)nt_descr - addr;
 366     code_start = page_size;
 367     data_start = delta & ~page_mask;
 368     data_end   = (nt->OptionalHeader.SizeOfImage + delta + page_mask) & ~page_mask;
 369
 370     fixup_rva_ptrs( &nt->OptionalHeader.AddressOfEntryPoint, addr, 1 );
 371
 372     nt->FileHeader.NumberOfSections                = nb_sections;
 373     nt->OptionalHeader.BaseOfCode                  = code_start;
 374 #ifndef _WIN64
 375     nt->OptionalHeader.BaseOfData                  = data_start;
 376 #endif
 377     nt->OptionalHeader.SizeOfCode                  = data_start - code_start;
 378     nt->OptionalHeader.SizeOfInitializedData       = data_end - data_start;
 379     nt->OptionalHeader.SizeOfUninitializedData     = 0;
 380     nt->OptionalHeader.SizeOfImage                 = data_end;
 381     nt->OptionalHeader.ImageBase                   = (ULONG_PTR)addr;
 382
 383     /* Build the code section */
 384
 385     memcpy( sec->Name, ".text", sizeof(".text") );
 386     sec->SizeOfRawData = data_start - code_start;
 387     sec->Misc.VirtualSize = sec->SizeOfRawData;
 388     sec->VirtualAddress   = code_start;
 389     sec->PointerToRawData = code_start;
 390     sec->Characteristics  = (IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ);
 391     sec++;
 392
 393     /* Build the data section */
 394
 395     memcpy( sec->Name, ".data", sizeof(".data") );
 396     sec->SizeOfRawData = data_end - data_start;
 397     sec->Misc.VirtualSize = sec->SizeOfRawData;
 398     sec->VirtualAddress   = data_start;
 399     sec->PointerToRawData = data_start;
 400     sec->Characteristics  = (IMAGE_SCN_CNT_INITIALIZED_DATA |
 401                              IMAGE_SCN_MEM_WRITE | IMAGE_SCN_MEM_READ);
 402     sec++;
 403
 404     for (i = 0; i < nt->OptionalHeader.NumberOfRvaAndSizes; i++)
 405         fixup_rva_dwords( &nt->OptionalHeader.DataDirectory[i].VirtualAddress, delta, 1 );
 406
 407     /* Build the import directory */
 408
 409     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_IMPORT_DIRECTORY];
 410     if (dir->Size)
 411     {
 412         IMAGE_IMPORT_DESCRIPTOR *imports = (void *)(addr + dir->VirtualAddress);
 413         fixup_imports( imports, addr, delta );
 414     }
 415
 416     /* Build the resource directory */
 417
 418     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_RESOURCE_DIRECTORY];
 419     if (dir->Size)
 420     {
 421         void *ptr = (void *)(addr + dir->VirtualAddress);
 422         fixup_resources( ptr, ptr, delta );
 423     }
 424
 425     /* Build the export directory */
 426
 427     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_EXPORT_DIRECTORY];
 428     if (dir->Size)
 429     {
 430         IMAGE_EXPORT_DIRECTORY *exports = (void *)(addr + dir->VirtualAddress);
 431         fixup_exports( exports, addr, delta );
 432     }
 433     return addr;
 434 #else  /* HAVE_MMAP */
 435     return NULL;
 436 #endif  /* HAVE_MMAP */
 437 }
 438
 439
 440 /***********************************************************************
 441  *           __wine_dll_register
 442  *
 443  * Register a built-in DLL descriptor.
 444  */
 445 void __wine_dll_register( const IMAGE_NT_HEADERS *header, const char *filename )
 446 {
 447     if (load_dll_callback) load_dll_callback( map_dll(header), filename );
 448     else
 449     {
 450         if (!(header->FileHeader.Characteristics & IMAGE_FILE_DLL))
 451             main_exe = header;
 452         else
 453         {
 454             assert( nb_dlls < MAX_DLLS );
 455             builtin_dlls[nb_dlls].nt = header;
 456             builtin_dlls[nb_dlls].filename = filename;
 457             nb_dlls++;
 458         }
 459     }
 460 }
 461
 462
 463 /***********************************************************************
 464  *           wine_dll_set_callback
 465  *
 466  * Set the callback function for dll loading, and call it
 467  * for all dlls that were implicitly loaded already.
 468  */
 469 void wine_dll_set_callback( load_dll_callback_t load )
 470 {
 471     int i;
 472     load_dll_callback = load;
 473     for (i = 0; i < nb_dlls; i++)
 474     {
 475         const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 476         if (!nt) continue;
 477         builtin_dlls[i].nt = NULL;
 478         load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 479     }
 480     nb_dlls = 0;
 481     if (main_exe) load_dll_callback( map_dll(main_exe), "" );
 482 }
 483
 484
 485 /***********************************************************************
 486  *           wine_dll_load
 487  *
 488  * Load a builtin dll.
 489  */
 490 void *wine_dll_load( const char *filename, char *error, int errorsize, int *file_exists )
 491 {
 492     int i;
 493
 494     /* callback must have been set already */
 495     assert( load_dll_callback );
 496
 497     /* check if we have it in the list */
 498     /* this can happen when initializing pre-loaded dlls in wine_dll_set_callback */
 499     for (i = 0; i < nb_dlls; i++)
 500     {
 501         if (!builtin_dlls[i].nt) continue;
 502         if (!strcmp( builtin_dlls[i].filename, filename ))
 503         {
 504             const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 505             builtin_dlls[i].nt = NULL;
 506             load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 507             *file_exists = 1;
 508             return (void *)1;
 509         }
 510     }
 511     return dlopen_dll( filename, error, errorsize, 0, file_exists );
 512 }
 513
 514
 515 /***********************************************************************
 516  *           wine_dll_unload
 517  *
 518  * Unload a builtin dll.
 519  */
 520 void wine_dll_unload( void *handle )
 521 {
 522     if (handle != (void *)1)
 523         wine_dlclose( handle, NULL, 0 );
 524 }
 525
 526
 527 /***********************************************************************
 528  *           wine_dll_load_main_exe
 529  *
 530  * Try to load the .so for the main exe.
 531  */
 532 void *wine_dll_load_main_exe( const char *name, char *error, int errorsize,
 533                               int test_only, int *file_exists )
 534 {
 535     return dlopen_dll( name, error, errorsize, test_only, file_exists );
 536 }
 537
 538
 539 /***********************************************************************
 540  *           wine_dll_enum_load_path
 541  *
 542  * Enumerate the dll load path.
 543  */
 544 const char *wine_dll_enum_load_path( unsigned int index )
 545 {
 546     if (index >= nb_dll_paths) return NULL;
 547     return dll_paths[index];
 548 }
 549
 550
 551 /***********************************************************************
 552  *           wine_dll_get_owner
 553  *
 554  * Retrieve the name of the 32-bit owner dll for a 16-bit dll.
 555  * Return 0 if OK, -1 on error.
 556  */
 557 int wine_dll_get_owner( const char *name, char *buffer, int size, int *exists )
 558 {
 559     int ret = -1;
 560     char *path;
 561     struct dll_path_context context;
 562
 563     *exists = 0;
 564
 565     for (path = first_dll_path( name, "16", &context ); path; path = next_dll_path( &context ))
 566     {
 567         int fd = open( path, O_RDONLY );
 568         if (fd != -1)
 569         {
 570             int res = read( fd, buffer, size - 1 );
 571             while (res > 0 && (buffer[res-1] == '\n' || buffer[res-1] == '\r')) res--;
 572             buffer[res] = 0;
 573             close( fd );
 574             *exists = 1;
 575             ret = 0;
 576             break;
 577         }
 578     }
 579     free_dll_path( &context );
 580     if (ret != -1) return ret;
 581
 582     /* try old method too for backwards compatibility; will be removed later on */
 583     for (path = first_dll_path( name, ".so", &context ); path; path = next_dll_path( &context ))
 584     {
 585         int res = readlink( path, buffer, size );
 586         if (res != -1) /* got a symlink */
 587         {
 588             *exists = 1;
 589             if (res < 4 || res >= size) break;
 590             buffer[res] = 0;
 591             if (strchr( buffer, '/' )) break;  /* contains a path, not valid */
 592             if (strcmp( buffer + res - 3, ".so" )) break;  /* does not end in .so, not valid */
 593             buffer[res - 3] = 0;  /* remove .so */
 594             ret = 0;
 595             break;
 596         }
 597         if ((*exists = file_exists( path ))) break; /* exists but not a symlink, return the error */
 598     }
 599     free_dll_path( &context );
 600     return ret;
 601 }
 602
 603
 604 /***********************************************************************
 605  *           set_max_limit
 606  *
 607  * Set a user limit to the maximum allowed value.
 608  */
 609 static void set_max_limit( int limit )
 610 {
 611     struct rlimit rlimit;
 612
 613     if (!getrlimit( limit, &rlimit ))
 614     {
 615         rlimit.rlim_cur = rlimit.rlim_max;
 616         setrlimit( limit, &rlimit );
 617     }
 618 }
 619
 620
 621 /***********************************************************************
 622  *           wine_init
 623  *
 624  * Main Wine initialisation.
 625  */
 626 void wine_init( int argc, char *argv[], char *error, int error_size )
 627 {
 628     struct dll_path_context context;
 629     char *path;
 630     void *ntdll = NULL;
 631     void (*init_func)(void);
 632
 633     /* force a few limits that are set too low on some platforms */
 634     set_max_limit( RLIMIT_NOFILE );
 635     set_max_limit( RLIMIT_AS );
 636
 637     wine_init_argv0_path( argv[0] );
 638     build_dll_path();
 639     __wine_main_argc = argc;
 640     __wine_main_argv = argv;
 641     __wine_main_environ = environ;
 642     mmap_init();
 643     debug_init();
 644
 645     for (path = first_dll_path( "ntdll.dll", ".so", &context ); path; path = next_dll_path( &context ))
 646     {
 647         if ((ntdll = wine_dlopen( path, RTLD_NOW, error, error_size )))
 648         {
 649             /* if we didn't use the default dll dir, remove it from the search path */
 650             if (default_dlldir[0] && context.index < nb_dll_paths) nb_dll_paths--;
 651             break;
 652         }
 653     }
 654     free_dll_path( &context );
 655
 656     if (!ntdll) return;
 657     if (!(init_func = wine_dlsym( ntdll, "__wine_process_init", error, error_size ))) return;
 658     init_func();
 659 }
 660
 661
 662 /*
 663  * These functions provide wrappers around dlopen() and associated
 664  * functions.  They work around a bug in glibc 2.1.x where calling
 665  * a dl*() function after a previous dl*() function has failed
 666  * without a dlerror() call between the two will cause a crash.
 667  * They all take a pointer to a buffer that
 668  * will receive the error description (from dlerror()).  This
 669  * parameter may be NULL if the error description is not required.
 670  */
 671
 672 #ifndef RTLD_FIRST
 673 #define RTLD_FIRST 0
 674 #endif
 675
 676 /***********************************************************************
 677  *              wine_dlopen
 678  */
 679 void *wine_dlopen( const char *filename, int flag, char *error, size_t errorsize )
 680 {
 681 #ifdef HAVE_DLOPEN
 682     void *ret;
 683     const char *s;
 684     dlerror(); dlerror();
 685     ret = dlopen( filename, flag | RTLD_FIRST );
 686     s = dlerror();
 687     if (error && errorsize)
 688     {
 689         if (s)
 690         {
 691             size_t len = strlen(s);
 692             if (len >= errorsize) len = errorsize - 1;
 693             memcpy( error, s, len );
 694             error[len] = 0;
 695         }
 696         else error[0] = 0;
 697     }
 698     dlerror();
 699     return ret;
 700 #else
 701     if (error)
 702     {
 703         static const char msg[] = "dlopen interface not detected by configure";
 704         size_t len = min( errorsize, sizeof(msg) );
 705         memcpy( error, msg, len );
 706         error[len - 1] = 0;
 707     }
 708     return NULL;
 709 #endif
 710 }
 711
 712 /***********************************************************************
 713  *              wine_dlsym
 714  */
 715 void *wine_dlsym( void *handle, const char *symbol, char *error, size_t errorsize )
 716 {
 717 #ifdef HAVE_DLOPEN
 718     void *ret;
 719     const char *s;
 720     dlerror(); dlerror();
 721     ret = dlsym( handle, symbol );
 722     s = dlerror();
 723     if (error && errorsize)
 724     {
 725         if (s)
 726         {
 727             size_t len = strlen(s);
 728             if (len >= errorsize) len = errorsize - 1;
 729             memcpy( error, s, len );
 730             error[len] = 0;
 731         }
 732         else error[0] = 0;
 733     }
 734     dlerror();
 735     return ret;
 736 #else
 737     if (error)
 738     {
 739         static const char msg[] = "dlopen interface not detected by configure";
 740         size_t len = min( errorsize, sizeof(msg) );
 741         memcpy( error, msg, len );
 742         error[len - 1] = 0;
 743     }
 744     return NULL;
 745 #endif
 746 }
 747
 748 /***********************************************************************
 749  *              wine_dlclose
 750  */
 751 int wine_dlclose( void *handle, char *error, size_t errorsize )
 752 {
 753 #ifdef HAVE_DLOPEN
 754     int ret;
 755     const char *s;
 756     dlerror(); dlerror();
 757     ret = dlclose( handle );
 758     s = dlerror();
 759     if (error && errorsize)
 760     {
 761         if (s)
 762         {
 763             size_t len = strlen(s);
 764             if (len >= errorsize) len = errorsize - 1;
 765             memcpy( error, s, len );
 766             error[len] = 0;
 767         }
 768         else error[0] = 0;
 769     }
 770     dlerror();
 771     return ret;
 772 #else
 773     if (error)
 774     {
 775         static const char msg[] = "dlopen interface not detected by configure";
 776         size_t len = min( errorsize, sizeof(msg) );
 777         memcpy( error, msg, len );
 778         error[len - 1] = 0;
 779     }
 780     return 1;
 781 #endif
 782 }