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 <limits.h>
  28 #include <stdarg.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <sys/types.h>
  32 #ifdef HAVE_SYS_MMAN_H
  33 #include <sys/mman.h>
  34 #endif
  35 #ifdef HAVE_SYS_RESOURCE_H
  36 # include <sys/resource.h>
  37 #endif
  38 #ifdef HAVE_UNISTD_H
  39 # include <unistd.h>
  40 #endif
  41
  42 #define NONAMELESSUNION
  43 #define NONAMELESSSTRUCT
  44 #include "windef.h"
  45 #include "winbase.h"
  46 #include "wine/library.h"
  47
  48 #ifdef __APPLE__
  49 #include <crt_externs.h>
  50 #define environ (*_NSGetEnviron())
  51 #else
  52 extern char **environ;
  53 #endif
  54
  55 /* argc/argv for the Windows application */
  56 int __wine_main_argc = 0;
  57 char **__wine_main_argv = NULL;
  58 WCHAR **__wine_main_wargv = NULL;
  59 char **__wine_main_environ = NULL;
  60
  61 struct dll_path_context
  62 {
  63     unsigned int index; /* current index in the dll path list */
  64     char *buffer;       /* buffer used for storing path names */
  65     char *name;         /* start of file name part in buffer (including leading slash) */
  66     int   namelen;      /* length of file name without .so extension */
  67     int   win16;        /* 16-bit dll search */
  68 };
  69
  70 #define MAX_DLLS 100
  71
  72 static struct
  73 {
  74     const IMAGE_NT_HEADERS *nt;           /* NT header */
  75     const char             *filename;     /* DLL file name */
  76 } builtin_dlls[MAX_DLLS];
  77
  78 static int nb_dlls;
  79
  80 static const IMAGE_NT_HEADERS *main_exe;
  81
  82 static load_dll_callback_t load_dll_callback;
  83
  84 static const char *build_dir;
  85 static const char *default_dlldir;
  86 static const char **dll_paths;
  87 static unsigned int nb_dll_paths;
  88 static int dll_path_maxlen;
  89
  90 extern void mmap_init(void);
  91 extern const char *get_dlldir( const char **default_dlldir );
  92
  93 /* build the dll load path from the WINEDLLPATH variable */
  94 static void build_dll_path(void)
  95 {
  96     int len, count = 0;
  97     char *p, *path = getenv( "WINEDLLPATH" );
  98     const char *dlldir = get_dlldir( &default_dlldir );
  99
 100     if (path)
 101     {
 102         /* count how many path elements we need */
 103         path = strdup(path);
 104         p = path;
 105         while (*p)
 106         {
 107             while (*p == ':') p++;
 108             if (!*p) break;
 109             count++;
 110             while (*p && *p != ':') p++;
 111         }
 112     }
 113
 114     dll_paths = malloc( (count+2) * sizeof(*dll_paths) );
 115     nb_dll_paths = 0;
 116
 117     if (dlldir)
 118     {
 119         dll_path_maxlen = strlen(dlldir);
 120         dll_paths[nb_dll_paths++] = dlldir;
 121     }
 122     else if ((build_dir = wine_get_build_dir()))
 123     {
 124         dll_path_maxlen = strlen(build_dir) + sizeof("/programs");
 125     }
 126
 127     if (count)
 128     {
 129         p = path;
 130         while (*p)
 131         {
 132             while (*p == ':') *p++ = 0;
 133             if (!*p) break;
 134             dll_paths[nb_dll_paths] = p;
 135             while (*p && *p != ':') p++;
 136             if (p - dll_paths[nb_dll_paths] > dll_path_maxlen)
 137                 dll_path_maxlen = p - dll_paths[nb_dll_paths];
 138             nb_dll_paths++;
 139         }
 140     }
 141
 142     /* append default dll dir (if not empty) to path */
 143     if ((len = strlen(default_dlldir)) > 0)
 144     {
 145         if (len > dll_path_maxlen) dll_path_maxlen = len;
 146         dll_paths[nb_dll_paths++] = default_dlldir;
 147     }
 148 }
 149
 150 /* check if a given file can be opened */
 151 static inline int file_exists( const char *name )
 152 {
 153     int fd = open( name, O_RDONLY );
 154     if (fd != -1) close( fd );
 155     return (fd != -1);
 156 }
 157
 158 static inline char *prepend( char *buffer, const char *str, size_t len )
 159 {
 160     return memcpy( buffer - len, str, len );
 161 }
 162
 163 /* get a filename from the next entry in the dll path */
 164 static char *next_dll_path( struct dll_path_context *context )
 165 {
 166     unsigned int index = context->index++;
 167     int namelen = context->namelen;
 168     char *path = context->name;
 169
 170     switch(index)
 171     {
 172     case 0:  /* try programs dir for .exe files */
 173         if (!context->win16 && namelen > 4 && !memcmp( context->name + namelen - 4, ".exe", 4 ))
 174         {
 175             path = prepend( path, context->name, namelen - 4 );
 176             path = prepend( path, "/programs", sizeof("/programs") - 1 );
 177             path = prepend( path, build_dir, strlen(build_dir) );
 178             return path;
 179         }
 180         context->index++;
 181         /* fall through */
 182     case 1:  /* try dlls dir with subdir prefix */
 183         if (namelen > 4 && !memcmp( context->name + namelen - 4, ".dll", 4 )) namelen -= 4;
 184         if (!context->win16) path = prepend( path, context->name, namelen );
 185         path = prepend( path, "/dlls", sizeof("/dlls") - 1 );
 186         path = prepend( path, build_dir, strlen(build_dir) );
 187         return path;
 188     default:
 189         index -= 2;
 190         if (index < nb_dll_paths)
 191             return prepend( context->name, dll_paths[index], strlen( dll_paths[index] ));
 192         break;
 193     }
 194     return NULL;
 195 }
 196
 197
 198 /* get a filename from the first entry in the dll path */
 199 static char *first_dll_path( const char *name, int win16, struct dll_path_context *context )
 200 {
 201     char *p;
 202     int namelen = strlen( name );
 203     const char *ext = win16 ? "16" : ".so";
 204
 205     context->buffer = malloc( dll_path_maxlen + 2 * namelen + strlen(ext) + 3 );
 206     context->index = build_dir ? 0 : 2;  /* 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     context->win16 = win16;
 210
 211     /* store the name at the end of the buffer, followed by extension */
 212     p = context->name;
 213     *p++ = '/';
 214     memcpy( p, name, namelen );
 215     strcpy( p + namelen, ext );
 216     return next_dll_path( context );
 217 }
 218
 219
 220 /* free the dll path context created by first_dll_path */
 221 static inline void free_dll_path( struct dll_path_context *context )
 222 {
 223     free( context->buffer );
 224 }
 225
 226
 227 /* open a library for a given dll, searching in the dll path
 228  * 'name' must be the Windows dll name (e.g. "kernel32.dll") */
 229 static void *dlopen_dll( const char *name, char *error, int errorsize,
 230                          int test_only, int *exists )
 231 {
 232     struct dll_path_context context;
 233     char *path;
 234     void *ret = NULL;
 235
 236     *exists = 0;
 237     for (path = first_dll_path( name, 0, &context ); path; path = next_dll_path( &context ))
 238     {
 239         if (!test_only && (ret = wine_dlopen( path, RTLD_NOW, error, errorsize ))) break;
 240         if ((*exists = file_exists( path ))) break; /* exists but cannot be loaded, return the error */
 241     }
 242     free_dll_path( &context );
 243     return ret;
 244 }
 245
 246
 247 /* adjust an array of pointers to make them into RVAs */
 248 static inline void fixup_rva_ptrs( void *array, BYTE *base, unsigned int count )
 249 {
 250     void **src = (void **)array;
 251     DWORD *dst = (DWORD *)array;
 252     while (count--)
 253     {
 254         *dst++ = *src ? (BYTE *)*src - base : 0;
 255         src++;
 256     }
 257 }
 258
 259 /* fixup an array of RVAs by adding the specified delta */
 260 static inline void fixup_rva_dwords( DWORD *ptr, int delta, unsigned int count )
 261 {
 262     while (count--)
 263     {
 264         if (*ptr) *ptr += delta;
 265         ptr++;
 266     }
 267 }
 268
 269
 270 /* fixup RVAs in the import directory */
 271 static void fixup_imports( IMAGE_IMPORT_DESCRIPTOR *dir, BYTE *base, int delta )
 272 {
 273     UINT_PTR *ptr;
 274
 275     while (dir->Name)
 276     {
 277         fixup_rva_dwords( &dir->u.OriginalFirstThunk, delta, 1 );
 278         fixup_rva_dwords( &dir->Name, delta, 1 );
 279         fixup_rva_dwords( &dir->FirstThunk, delta, 1 );
 280         ptr = (UINT_PTR *)(base + dir->FirstThunk);
 281         while (*ptr)
 282         {
 283             if (!(*ptr & IMAGE_ORDINAL_FLAG)) *ptr += delta;
 284             ptr++;
 285         }
 286         dir++;
 287     }
 288 }
 289
 290
 291 /* fixup RVAs in the export directory */
 292 static void fixup_exports( IMAGE_EXPORT_DIRECTORY *dir, BYTE *base, int delta )
 293 {
 294     fixup_rva_dwords( &dir->Name, delta, 1 );
 295     fixup_rva_dwords( &dir->AddressOfFunctions, delta, 1 );
 296     fixup_rva_dwords( &dir->AddressOfNames, delta, 1 );
 297     fixup_rva_dwords( &dir->AddressOfNameOrdinals, delta, 1 );
 298     fixup_rva_dwords( (DWORD *)(base + dir->AddressOfNames), delta, dir->NumberOfNames );
 299     fixup_rva_ptrs( (base + dir->AddressOfFunctions), base, dir->NumberOfFunctions );
 300 }
 301
 302
 303 /* fixup RVAs in the resource directory */
 304 static void fixup_resources( IMAGE_RESOURCE_DIRECTORY *dir, BYTE *root, int delta )
 305 {
 306     IMAGE_RESOURCE_DIRECTORY_ENTRY *entry;
 307     int i;
 308
 309     entry = (IMAGE_RESOURCE_DIRECTORY_ENTRY *)(dir + 1);
 310     for (i = 0; i < dir->NumberOfNamedEntries + dir->NumberOfIdEntries; i++, entry++)
 311     {
 312         void *ptr = root + entry->u2.s3.OffsetToDirectory;
 313         if (entry->u2.s3.DataIsDirectory) fixup_resources( ptr, root, delta );
 314         else
 315         {
 316             IMAGE_RESOURCE_DATA_ENTRY *data = ptr;
 317             fixup_rva_dwords( &data->OffsetToData, delta, 1 );
 318         }
 319     }
 320 }
 321
 322
 323 /* map a builtin dll in memory and fixup RVAs */
 324 static void *map_dll( const IMAGE_NT_HEADERS *nt_descr )
 325 {
 326 #ifdef HAVE_MMAP
 327     IMAGE_DATA_DIRECTORY *dir;
 328     IMAGE_DOS_HEADER *dos;
 329     IMAGE_NT_HEADERS *nt;
 330     IMAGE_SECTION_HEADER *sec;
 331     BYTE *addr;
 332     DWORD code_start, data_start, data_end;
 333     const size_t page_size = getpagesize();
 334     const size_t page_mask = page_size - 1;
 335     int delta, nb_sections = 2;  /* code + data */
 336     unsigned int i;
 337
 338     size_t size = (sizeof(IMAGE_DOS_HEADER)
 339                    + sizeof(IMAGE_NT_HEADERS)
 340                    + nb_sections * sizeof(IMAGE_SECTION_HEADER));
 341
 342     assert( size <= page_size );
 343
 344     /* module address must be aligned on 64K boundary */
 345     addr = (BYTE *)((nt_descr->OptionalHeader.ImageBase + 0xffff) & ~0xffff);
 346     if (wine_anon_mmap( addr, page_size, PROT_READ|PROT_WRITE, MAP_FIXED ) != addr) return NULL;
 347
 348     dos    = (IMAGE_DOS_HEADER *)addr;
 349     nt     = (IMAGE_NT_HEADERS *)(dos + 1);
 350     sec    = (IMAGE_SECTION_HEADER *)(nt + 1);
 351
 352     /* Build the DOS and NT headers */
 353
 354     dos->e_magic    = IMAGE_DOS_SIGNATURE;
 355     dos->e_cblp     = 0x90;
 356     dos->e_cp       = 3;
 357     dos->e_cparhdr  = (sizeof(*dos)+0xf)/0x10;
 358     dos->e_minalloc = 0;
 359     dos->e_maxalloc = 0xffff;
 360     dos->e_ss       = 0x0000;
 361     dos->e_sp       = 0x00b8;
 362     dos->e_lfarlc   = sizeof(*dos);
 363     dos->e_lfanew   = sizeof(*dos);
 364
 365     *nt = *nt_descr;
 366
 367     delta      = (const BYTE *)nt_descr - addr;
 368     code_start = page_size;
 369     data_start = delta & ~page_mask;
 370     data_end   = (nt->OptionalHeader.SizeOfImage + delta + page_mask) & ~page_mask;
 371
 372     fixup_rva_ptrs( &nt->OptionalHeader.AddressOfEntryPoint, addr, 1 );
 373
 374     nt->FileHeader.NumberOfSections                = nb_sections;
 375     nt->OptionalHeader.BaseOfCode                  = code_start;
 376 #ifndef _WIN64
 377     nt->OptionalHeader.BaseOfData                  = data_start;
 378 #endif
 379     nt->OptionalHeader.SizeOfCode                  = data_start - code_start;
 380     nt->OptionalHeader.SizeOfInitializedData       = data_end - data_start;
 381     nt->OptionalHeader.SizeOfUninitializedData     = 0;
 382     nt->OptionalHeader.SizeOfImage                 = data_end;
 383     nt->OptionalHeader.ImageBase                   = (ULONG_PTR)addr;
 384
 385     /* Build the code section */
 386
 387     memcpy( sec->Name, ".text", sizeof(".text") );
 388     sec->SizeOfRawData = data_start - code_start;
 389     sec->Misc.VirtualSize = sec->SizeOfRawData;
 390     sec->VirtualAddress   = code_start;
 391     sec->PointerToRawData = code_start;
 392     sec->Characteristics  = (IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ);
 393     sec++;
 394
 395     /* Build the data section */
 396
 397     memcpy( sec->Name, ".data", sizeof(".data") );
 398     sec->SizeOfRawData = data_end - data_start;
 399     sec->Misc.VirtualSize = sec->SizeOfRawData;
 400     sec->VirtualAddress   = data_start;
 401     sec->PointerToRawData = data_start;
 402     sec->Characteristics  = (IMAGE_SCN_CNT_INITIALIZED_DATA |
 403                              IMAGE_SCN_MEM_WRITE | IMAGE_SCN_MEM_READ);
 404     sec++;
 405
 406     for (i = 0; i < nt->OptionalHeader.NumberOfRvaAndSizes; i++)
 407         fixup_rva_dwords( &nt->OptionalHeader.DataDirectory[i].VirtualAddress, delta, 1 );
 408
 409     /* Build the import directory */
 410
 411     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_IMPORT_DIRECTORY];
 412     if (dir->Size)
 413     {
 414         IMAGE_IMPORT_DESCRIPTOR *imports = (void *)(addr + dir->VirtualAddress);
 415         fixup_imports( imports, addr, delta );
 416     }
 417
 418     /* Build the resource directory */
 419
 420     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_RESOURCE_DIRECTORY];
 421     if (dir->Size)
 422     {
 423         void *ptr = (void *)(addr + dir->VirtualAddress);
 424         fixup_resources( ptr, ptr, delta );
 425     }
 426
 427     /* Build the export directory */
 428
 429     dir = &nt->OptionalHeader.DataDirectory[IMAGE_FILE_EXPORT_DIRECTORY];
 430     if (dir->Size)
 431     {
 432         IMAGE_EXPORT_DIRECTORY *exports = (void *)(addr + dir->VirtualAddress);
 433         fixup_exports( exports, addr, delta );
 434     }
 435     return addr;
 436 #else  /* HAVE_MMAP */
 437     return NULL;
 438 #endif  /* HAVE_MMAP */
 439 }
 440
 441
 442 /***********************************************************************
 443  *           __wine_dll_register
 444  *
 445  * Register a built-in DLL descriptor.
 446  */
 447 void __wine_dll_register( const IMAGE_NT_HEADERS *header, const char *filename )
 448 {
 449     if (load_dll_callback) load_dll_callback( map_dll(header), filename );
 450     else
 451     {
 452         if (!(header->FileHeader.Characteristics & IMAGE_FILE_DLL))
 453             main_exe = header;
 454         else
 455         {
 456             assert( nb_dlls < MAX_DLLS );
 457             builtin_dlls[nb_dlls].nt = header;
 458             builtin_dlls[nb_dlls].filename = filename;
 459             nb_dlls++;
 460         }
 461     }
 462 }
 463
 464
 465 /***********************************************************************
 466  *           wine_dll_set_callback
 467  *
 468  * Set the callback function for dll loading, and call it
 469  * for all dlls that were implicitly loaded already.
 470  */
 471 void wine_dll_set_callback( load_dll_callback_t load )
 472 {
 473     int i;
 474     load_dll_callback = load;
 475     for (i = 0; i < nb_dlls; i++)
 476     {
 477         const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 478         if (!nt) continue;
 479         builtin_dlls[i].nt = NULL;
 480         load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 481     }
 482     nb_dlls = 0;
 483     if (main_exe) load_dll_callback( map_dll(main_exe), "" );
 484 }
 485
 486
 487 /***********************************************************************
 488  *           wine_dll_load
 489  *
 490  * Load a builtin dll.
 491  */
 492 void *wine_dll_load( const char *filename, char *error, int errorsize, int *file_exists )
 493 {
 494     int i;
 495
 496     /* callback must have been set already */
 497     assert( load_dll_callback );
 498
 499     /* check if we have it in the list */
 500     /* this can happen when initializing pre-loaded dlls in wine_dll_set_callback */
 501     for (i = 0; i < nb_dlls; i++)
 502     {
 503         if (!builtin_dlls[i].nt) continue;
 504         if (!strcmp( builtin_dlls[i].filename, filename ))
 505         {
 506             const IMAGE_NT_HEADERS *nt = builtin_dlls[i].nt;
 507             builtin_dlls[i].nt = NULL;
 508             load_dll_callback( map_dll(nt), builtin_dlls[i].filename );
 509             *file_exists = 1;
 510             return (void *)1;
 511         }
 512     }
 513     return dlopen_dll( filename, error, errorsize, 0, file_exists );
 514 }
 515
 516
 517 /***********************************************************************
 518  *           wine_dll_unload
 519  *
 520  * Unload a builtin dll.
 521  */
 522 void wine_dll_unload( void *handle )
 523 {
 524     if (handle != (void *)1)
 525         wine_dlclose( handle, NULL, 0 );
 526 }
 527
 528
 529 /***********************************************************************
 530  *           wine_dll_load_main_exe
 531  *
 532  * Try to load the .so for the main exe.
 533  */
 534 void *wine_dll_load_main_exe( const char *name, char *error, int errorsize,
 535                               int test_only, int *file_exists )
 536 {
 537     return dlopen_dll( name, error, errorsize, test_only, file_exists );
 538 }
 539
 540
 541 /***********************************************************************
 542  *           wine_dll_enum_load_path
 543  *
 544  * Enumerate the dll load path.
 545  */
 546 const char *wine_dll_enum_load_path( unsigned int index )
 547 {
 548     if (index >= nb_dll_paths) return NULL;
 549     return dll_paths[index];
 550 }
 551
 552
 553 /***********************************************************************
 554  *           wine_dll_get_owner
 555  *
 556  * Retrieve the name of the 32-bit owner dll for a 16-bit dll.
 557  * Return 0 if OK, -1 on error.
 558  */
 559 int wine_dll_get_owner( const char *name, char *buffer, int size, int *exists )
 560 {
 561     int ret = -1;
 562     char *path;
 563     struct dll_path_context context;
 564
 565     *exists = 0;
 566
 567     for (path = first_dll_path( name, 1, &context ); path; path = next_dll_path( &context ))
 568     {
 569         int fd = open( path, O_RDONLY );
 570         if (fd != -1)
 571         {
 572             int res = read( fd, buffer, size - 1 );
 573             while (res > 0 && (buffer[res-1] == '\n' || buffer[res-1] == '\r')) res--;
 574             buffer[res] = 0;
 575             close( fd );
 576             *exists = 1;
 577             ret = 0;
 578             break;
 579         }
 580     }
 581     free_dll_path( &context );
 582     return ret;
 583 }
 584
 585
 586 /***********************************************************************
 587  *           set_max_limit
 588  *
 589  * Set a user limit to the maximum allowed value.
 590  */
 591 static void set_max_limit( int limit )
 592 {
 593 #ifdef HAVE_SETRLIMIT
 594     struct rlimit rlimit;
 595
 596     if (!getrlimit( limit, &rlimit ))
 597     {
 598         rlimit.rlim_cur = rlimit.rlim_max;
 599         if (setrlimit( limit, &rlimit ) != 0)
 600         {
 601 #if defined(__APPLE__) && defined(RLIMIT_NOFILE) && defined(OPEN_MAX)
 602             /* On Leopard, setrlimit(RLIMIT_NOFILE, ...) fails on attempts to set
 603              * rlim_cur above OPEN_MAX (even if rlim_max > OPEN_MAX). */
 604             if (limit == RLIMIT_NOFILE && rlimit.rlim_cur > OPEN_MAX)
 605             {
 606                 rlimit.rlim_cur = OPEN_MAX;
 607                 setrlimit( limit, &rlimit );
 608             }
 609 #endif
 610         }
 611     }
 612 #endif
 613 }
 614
 615
 616 /***********************************************************************
 617  *           wine_init
 618  *
 619  * Main Wine initialisation.
 620  */
 621 void wine_init( int argc, char *argv[], char *error, int error_size )
 622 {
 623     struct dll_path_context context;
 624     char *path;
 625     void *ntdll = NULL;
 626     void (*init_func)(void);
 627
 628     /* force a few limits that are set too low on some platforms */
 629 #ifdef RLIMIT_NOFILE
 630     set_max_limit( RLIMIT_NOFILE );
 631 #endif
 632 #ifdef RLIMIT_AS
 633     set_max_limit( RLIMIT_AS );
 634 #endif
 635
 636     wine_init_argv0_path( argv[0] );
 637     build_dll_path();
 638     __wine_main_argc = argc;
 639     __wine_main_argv = argv;
 640     __wine_main_environ = environ;
 641     mmap_init();
 642
 643     for (path = first_dll_path( "ntdll.dll", 0, &context ); path; path = next_dll_path( &context ))
 644     {
 645         if ((ntdll = wine_dlopen( path, RTLD_NOW, error, error_size )))
 646         {
 647             /* if we didn't use the default dll dir, remove it from the search path */
 648             if (default_dlldir[0] && context.index < nb_dll_paths + 2) nb_dll_paths--;
 649             break;
 650         }
 651     }
 652     free_dll_path( &context );
 653
 654     if (!ntdll) return;
 655     if (!(init_func = wine_dlsym( ntdll, "__wine_process_init", error, error_size ))) return;
 656     init_func();
 657 }
 658
 659
 660 /*
 661  * These functions provide wrappers around dlopen() and associated
 662  * functions.  They work around a bug in glibc 2.1.x where calling
 663  * a dl*() function after a previous dl*() function has failed
 664  * without a dlerror() call between the two will cause a crash.
 665  * They all take a pointer to a buffer that
 666  * will receive the error description (from dlerror()).  This
 667  * parameter may be NULL if the error description is not required.
 668  */
 669
 670 #ifndef RTLD_FIRST
 671 #define RTLD_FIRST 0
 672 #endif
 673
 674 /***********************************************************************
 675  *              wine_dlopen
 676  */
 677 void *wine_dlopen( const char *filename, int flag, char *error, size_t errorsize )
 678 {
 679 #ifdef HAVE_DLOPEN
 680     void *ret;
 681     const char *s;
 682
 683 #ifdef __APPLE__
 684     /* the Mac OS loader pretends to be able to load PE files, so avoid them here */
 685     unsigned char magic[2];
 686     int fd = open( filename, O_RDONLY );
 687     if (fd != -1)
 688     {
 689         if (pread( fd, magic, 2, 0 ) == 2 && magic[0] == 'M' && magic[1] == 'Z')
 690         {
 691             static const char msg[] = "MZ format";
 692             size_t len = min( errorsize, sizeof(msg) );
 693             memcpy( error, msg, len );
 694             error[len - 1] = 0;
 695             close( fd );
 696             return NULL;
 697         }
 698         close( fd );
 699     }
 700 #endif
 701     dlerror(); dlerror();
 702 #ifdef __sun
 703     if (strchr( filename, ':' ))
 704     {
 705         char path[PATH_MAX];
 706         /* Solaris' brain damaged dlopen() treats ':' as a path separator */
 707         realpath( filename, path );
 708         ret = dlopen( path, flag | RTLD_FIRST );
 709     }
 710     else
 711 #endif
 712     ret = dlopen( filename, flag | RTLD_FIRST );
 713     s = dlerror();
 714     if (error && errorsize)
 715     {
 716         if (s)
 717         {
 718             size_t len = strlen(s);
 719             if (len >= errorsize) len = errorsize - 1;
 720             memcpy( error, s, len );
 721             error[len] = 0;
 722         }
 723         else error[0] = 0;
 724     }
 725     dlerror();
 726     return ret;
 727 #else
 728     if (error)
 729     {
 730         static const char msg[] = "dlopen interface not detected by configure";
 731         size_t len = min( errorsize, sizeof(msg) );
 732         memcpy( error, msg, len );
 733         error[len - 1] = 0;
 734     }
 735     return NULL;
 736 #endif
 737 }
 738
 739 /***********************************************************************
 740  *              wine_dlsym
 741  */
 742 void *wine_dlsym( void *handle, const char *symbol, char *error, size_t errorsize )
 743 {
 744 #ifdef HAVE_DLOPEN
 745     void *ret;
 746     const char *s;
 747     dlerror(); dlerror();
 748     ret = dlsym( handle, symbol );
 749     s = dlerror();
 750     if (error && errorsize)
 751     {
 752         if (s)
 753         {
 754             size_t len = strlen(s);
 755             if (len >= errorsize) len = errorsize - 1;
 756             memcpy( error, s, len );
 757             error[len] = 0;
 758         }
 759         else error[0] = 0;
 760     }
 761     dlerror();
 762     return ret;
 763 #else
 764     if (error)
 765     {
 766         static const char msg[] = "dlopen interface not detected by configure";
 767         size_t len = min( errorsize, sizeof(msg) );
 768         memcpy( error, msg, len );
 769         error[len - 1] = 0;
 770     }
 771     return NULL;
 772 #endif
 773 }
 774
 775 /***********************************************************************
 776  *              wine_dlclose
 777  */
 778 int wine_dlclose( void *handle, char *error, size_t errorsize )
 779 {
 780 #ifdef HAVE_DLOPEN
 781     int ret;
 782     const char *s;
 783     dlerror(); dlerror();
 784     ret = dlclose( handle );
 785     s = dlerror();
 786     if (error && errorsize)
 787     {
 788         if (s)
 789         {
 790             size_t len = strlen(s);
 791             if (len >= errorsize) len = errorsize - 1;
 792             memcpy( error, s, len );
 793             error[len] = 0;
 794         }
 795         else error[0] = 0;
 796     }
 797     dlerror();
 798     return ret;
 799 #else
 800     if (error)
 801     {
 802         static const char msg[] = "dlopen interface not detected by configure";
 803         size_t len = min( errorsize, sizeof(msg) );
 804         memcpy( error, msg, len );
 805         error[len - 1] = 0;
 806     }
 807     return 1;
 808 #endif
 809 }