dlls/kernel32/virtual.c

   1 /*
   2  * Win32 virtual memory functions
   3  *
   4  * Copyright 1997 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 <fcntl.h>
  25 #include <stdarg.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <sys/types.h>
  29 #ifdef HAVE_UNISTD_H
  30 # include <unistd.h>
  31 #endif
  32
  33 #define NONAMELESSUNION
  34 #define NONAMELESSSTRUCT
  35 #include "ntstatus.h"
  36 #define WIN32_NO_STATUS
  37 #include "windef.h"
  38 #include "winbase.h"
  39 #include "winnls.h"
  40 #include "winternl.h"
  41 #include "winerror.h"
  42 #include "wine/exception.h"
  43 #include "wine/debug.h"
  44
  45 #include "kernel_private.h"
  46
  47 WINE_DECLARE_DEBUG_CHANNEL(seh);
  48
  49 static unsigned int page_size;
  50
  51
  52 /***********************************************************************
  53  *             VirtualAlloc   (KERNEL32.@)
  54  *
  55  * Reserves or commits a region of pages in virtual address space.
  56  *
  57  * PARAMS
  58  *  addr    [I] Address of region to reserve or commit.
  59  *  size    [I] Size of region.
  60  *  type    [I] Type of allocation.
  61  *  protect [I] Type of access protection.
  62  *
  63  * RETURNS
  64  *      Success: Base address of allocated region of pages.
  65  *      Failure: NULL.
  66  */
  67 LPVOID WINAPI VirtualAlloc( LPVOID addr, SIZE_T size, DWORD type, DWORD protect )
  68 {
  69     return VirtualAllocEx( GetCurrentProcess(), addr, size, type, protect );
  70 }
  71
  72
  73 /***********************************************************************
  74  *             VirtualAllocEx   (KERNEL32.@)
  75  *
  76  * Seems to be just as VirtualAlloc, but with process handle.
  77  *
  78  * PARAMS
  79  *  hProcess [I] Handle to process to do mem operation.
  80  *  addr     [I] Address of region to reserve or commit.
  81  *  size     [I] Size of region.
  82  *  type     [I] Type of allocation.
  83  *  protect  [I] Type of access protection.
  84  *
  85  *
  86  * RETURNS
  87  *      Success: Base address of allocated region of pages.
  88  *      Failure: NULL.
  89  */
  90 LPVOID WINAPI VirtualAllocEx( HANDLE hProcess, LPVOID addr, SIZE_T size,
  91     DWORD type, DWORD protect )
  92 {
  93     LPVOID ret = addr;
  94     NTSTATUS status;
  95
  96     if ((status = NtAllocateVirtualMemory( hProcess, &ret, 0, &size, type, protect )))
  97     {
  98         SetLastError( RtlNtStatusToDosError(status) );
  99         ret = NULL;
 100     }
 101     return ret;
 102 }
 103
 104
 105 /***********************************************************************
 106  *             VirtualFree   (KERNEL32.@)
 107  *
 108  * Releases or decommits a region of pages in virtual address space.
 109  *
 110  * PARAMS
 111  *  addr [I] Address of region of committed pages.
 112  *  size [I] Size of region.
 113  *  type [I] Type of operation.
 114  *
 115  * RETURNS
 116  *      Success: TRUE.
 117  *      Failure: FALSE.
 118  */
 119 BOOL WINAPI VirtualFree( LPVOID addr, SIZE_T size, DWORD type )
 120 {
 121     return VirtualFreeEx( GetCurrentProcess(), addr, size, type );
 122 }
 123
 124
 125 /***********************************************************************
 126  *             VirtualFreeEx   (KERNEL32.@)
 127  *
 128  * Releases or decommits a region of pages in virtual address space.
 129  *
 130  * PARAMS
 131  *  process [I] Handle to process.
 132  *  addr    [I] Address of region to free.
 133  *  size    [I] Size of region.
 134  *  type    [I] Type of operation.
 135  *
 136  * RETURNS
 137  *      Success: TRUE.
 138  *      Failure: FALSE.
 139  */
 140 BOOL WINAPI VirtualFreeEx( HANDLE process, LPVOID addr, SIZE_T size, DWORD type )
 141 {
 142     NTSTATUS status = NtFreeVirtualMemory( process, &addr, &size, type );
 143     if (status) SetLastError( RtlNtStatusToDosError(status) );
 144     return !status;
 145 }
 146
 147
 148 /***********************************************************************
 149  *             VirtualLock   (KERNEL32.@)
 150  *
 151  * Locks the specified region of virtual address space.
 152  *
 153  * PARAMS
 154  *  addr [I] Address of first byte of range to lock.
 155  *  size [I] Number of bytes in range to lock.
 156  *
 157  * RETURNS
 158  *      Success: TRUE.
 159  *      Failure: FALSE.
 160  *
 161  * NOTES
 162  *      Always returns TRUE.
 163  *
 164  */
 165 BOOL WINAPI VirtualLock( LPVOID addr, SIZE_T size )
 166 {
 167     NTSTATUS status = NtLockVirtualMemory( GetCurrentProcess(), &addr, &size, 1 );
 168     if (status) SetLastError( RtlNtStatusToDosError(status) );
 169     return !status;
 170 }
 171
 172
 173 /***********************************************************************
 174  *             VirtualUnlock   (KERNEL32.@)
 175  *
 176  * Unlocks a range of pages in the virtual address space.
 177  *
 178  * PARAMS
 179  *  addr [I] Address of first byte of range.
 180  *  size [I] Number of bytes in range.
 181  *
 182  * RETURNS
 183  *      Success: TRUE.
 184  *      Failure: FALSE.
 185  *
 186  * NOTES
 187  *      Always returns TRUE.
 188  *
 189  */
 190 BOOL WINAPI VirtualUnlock( LPVOID addr, SIZE_T size )
 191 {
 192     NTSTATUS status = NtUnlockVirtualMemory( GetCurrentProcess(), &addr, &size, 1 );
 193     if (status) SetLastError( RtlNtStatusToDosError(status) );
 194     return !status;
 195 }
 196
 197
 198 /***********************************************************************
 199  *             VirtualProtect   (KERNEL32.@)
 200  *
 201  * Changes the access protection on a region of committed pages.
 202  *
 203  * PARAMS
 204  *  addr     [I] Address of region of committed pages.
 205  *  size     [I] Size of region.
 206  *  new_prot [I] Desired access protection.
 207  *  old_prot [O] Address of variable to get old protection.
 208  *
 209  * RETURNS
 210  *      Success: TRUE.
 211  *      Failure: FALSE.
 212  */
 213 BOOL WINAPI VirtualProtect( LPVOID addr, SIZE_T size, DWORD new_prot, LPDWORD old_prot)
 214 {
 215     return VirtualProtectEx( GetCurrentProcess(), addr, size, new_prot, old_prot );
 216 }
 217
 218
 219 /***********************************************************************
 220  *             VirtualProtectEx   (KERNEL32.@)
 221  *
 222  * Changes the access protection on a region of committed pages in the
 223  * virtual address space of a specified process.
 224  *
 225  * PARAMS
 226  *  process  [I] Handle of process.
 227  *  addr     [I] Address of region of committed pages.
 228  *  size     [I] Size of region.
 229  *  new_prot [I] Desired access protection.
 230  *  old_prot [O] Address of variable to get old protection.
 231  *
 232  * RETURNS
 233  *      Success: TRUE.
 234  *      Failure: FALSE.
 235  */
 236 BOOL WINAPI VirtualProtectEx( HANDLE process, LPVOID addr, SIZE_T size,
 237     DWORD new_prot, LPDWORD old_prot )
 238 {
 239     NTSTATUS status = NtProtectVirtualMemory( process, &addr, &size, new_prot, old_prot );
 240     if (status) SetLastError( RtlNtStatusToDosError(status) );
 241     return !status;
 242 }
 243
 244
 245 /***********************************************************************
 246  *             VirtualQuery   (KERNEL32.@)
 247  *
 248  * Provides info about a range of pages in virtual address space.
 249  *
 250  * PARAMS
 251  *  addr [I] Address of region.
 252  *  info [O] Address of info buffer.
 253  *  len  [I] Size of buffer.
 254  *
 255  * RETURNS
 256  *      Number of bytes returned in information buffer or 0 if
 257  *      addr >= 0xc0000000 (kernel space).
 258  */
 259 SIZE_T WINAPI VirtualQuery( LPCVOID addr, PMEMORY_BASIC_INFORMATION info,
 260     SIZE_T len )
 261 {
 262     return VirtualQueryEx( GetCurrentProcess(), addr, info, len );
 263 }
 264
 265
 266 /***********************************************************************
 267  *             VirtualQueryEx   (KERNEL32.@)
 268  *
 269  * Provides info about a range of pages in virtual address space of a
 270  * specified process.
 271  *
 272  * PARAMS
 273  *  process [I] Handle to process.
 274  *  addr    [I] Address of region.
 275  *  info    [O] Address of info buffer.
 276  *  len     [I] Size of buffer.
 277  *
 278  * RETURNS
 279  *      Number of bytes returned in information buffer.
 280  */
 281 SIZE_T WINAPI VirtualQueryEx( HANDLE process, LPCVOID addr,
 282     PMEMORY_BASIC_INFORMATION info, SIZE_T len )
 283 {
 284     SIZE_T ret;
 285     NTSTATUS status;
 286
 287     if ((status = NtQueryVirtualMemory( process, addr, MemoryBasicInformation, info, len, &ret )))
 288     {
 289         SetLastError( RtlNtStatusToDosError(status) );
 290         ret = 0;
 291     }
 292     return ret;
 293 }
 294
 295
 296 /***********************************************************************
 297  *             CreateFileMappingA   (KERNEL32.@)
 298  *
 299  * Creates a named or unnamed file-mapping object for the specified file.
 300  *
 301  * PARAMS
 302  *  hFile     [I] Handle to the file to map.
 303  *  sa        [I] Optional security attributes.
 304  *  protect   [I] Protection for mapping object.
 305  *  size_high [I] High-order 32 bits of object size.
 306  *  size_low  [I] Low-order 32 bits of object size.
 307  *  name      [I] Name of file-mapping object.
 308  *
 309  * RETURNS
 310  *      Success: Handle.
 311  *      Failure: NULL. Mapping object does not exist.
 312  */
 313 HANDLE WINAPI CreateFileMappingA( HANDLE hFile, SECURITY_ATTRIBUTES *sa,
 314     DWORD protect, DWORD size_high, DWORD size_low, LPCSTR name )
 315 {
 316     WCHAR buffer[MAX_PATH];
 317
 318     if (!name) return CreateFileMappingW( hFile, sa, protect, size_high, size_low, NULL );
 319
 320     if (!MultiByteToWideChar( CP_ACP, 0, name, -1, buffer, MAX_PATH ))
 321     {
 322         SetLastError( ERROR_FILENAME_EXCED_RANGE );
 323         return 0;
 324     }
 325     return CreateFileMappingW( hFile, sa, protect, size_high, size_low, buffer );
 326 }
 327
 328
 329 /***********************************************************************
 330  *             CreateFileMappingW   (KERNEL32.@)
 331  *
 332  * See CreateFileMappingA.
 333  */
 334 HANDLE WINAPI CreateFileMappingW( HANDLE hFile, LPSECURITY_ATTRIBUTES sa,
 335                                   DWORD protect, DWORD size_high,
 336                                   DWORD size_low, LPCWSTR name )
 337 {
 338     static const int sec_flags = SEC_FILE | SEC_IMAGE | SEC_RESERVE | SEC_COMMIT | SEC_NOCACHE;
 339
 340     HANDLE ret;
 341     NTSTATUS status;
 342     DWORD access, sec_type;
 343     LARGE_INTEGER size;
 344
 345     sec_type = protect & sec_flags;
 346     protect &= ~sec_flags;
 347     if (!sec_type) sec_type = SEC_COMMIT;
 348
 349     switch(protect)
 350     {
 351     case 0:
 352         protect = PAGE_READONLY;  /* Win9x compatibility */
 353         /* fall through */
 354     case PAGE_READONLY:
 355     case PAGE_WRITECOPY:
 356         access = STANDARD_RIGHTS_REQUIRED | SECTION_QUERY | SECTION_MAP_READ | SECTION_MAP_EXECUTE;
 357         break;
 358     case PAGE_READWRITE:
 359         access = STANDARD_RIGHTS_REQUIRED | SECTION_QUERY | SECTION_MAP_READ | SECTION_MAP_WRITE | SECTION_MAP_EXECUTE;
 360         break;
 361     case PAGE_EXECUTE:
 362         access = STANDARD_RIGHTS_REQUIRED | SECTION_QUERY | SECTION_MAP_EXECUTE | SECTION_MAP_EXECUTE_EXPLICIT;
 363         break;
 364     case PAGE_EXECUTE_READ:
 365     case PAGE_EXECUTE_WRITECOPY:
 366         access = STANDARD_RIGHTS_REQUIRED | SECTION_QUERY | SECTION_MAP_READ | SECTION_MAP_EXECUTE | SECTION_MAP_EXECUTE_EXPLICIT;
 367         break;
 368     case PAGE_EXECUTE_READWRITE:
 369         access = STANDARD_RIGHTS_REQUIRED | SECTION_QUERY | SECTION_MAP_READ | SECTION_MAP_WRITE | SECTION_MAP_EXECUTE | SECTION_MAP_EXECUTE_EXPLICIT;
 370         break;
 371     default:
 372         SetLastError( ERROR_INVALID_PARAMETER );
 373         return 0;
 374     }
 375
 376     if (hFile == INVALID_HANDLE_VALUE)
 377     {
 378         hFile = 0;
 379         if (!size_low && !size_high)
 380         {
 381             SetLastError( ERROR_INVALID_PARAMETER );
 382             return 0;
 383         }
 384     }
 385
 386     size.u.LowPart  = size_low;
 387     size.u.HighPart = size_high;
 388
 389     if (sa || name)
 390     {
 391         OBJECT_ATTRIBUTES attr;
 392         UNICODE_STRING nameW;
 393
 394         attr.Length                   = sizeof(attr);
 395         attr.RootDirectory            = 0;
 396         attr.ObjectName               = NULL;
 397         attr.Attributes               = OBJ_OPENIF | ((sa && sa->bInheritHandle) ? OBJ_INHERIT : 0);
 398         attr.SecurityDescriptor       = sa ? sa->lpSecurityDescriptor : NULL;
 399         attr.SecurityQualityOfService = NULL;
 400         if (name)
 401         {
 402             RtlInitUnicodeString( &nameW, name );
 403             attr.ObjectName = &nameW;
 404             attr.RootDirectory = get_BaseNamedObjects_handle();
 405         }
 406         status = NtCreateSection( &ret, access, &attr, &size, protect, sec_type, hFile );
 407     }
 408     else status = NtCreateSection( &ret, access, NULL, &size, protect, sec_type, hFile );
 409
 410     if (status == STATUS_OBJECT_NAME_EXISTS)
 411         SetLastError( ERROR_ALREADY_EXISTS );
 412     else
 413         SetLastError( RtlNtStatusToDosError(status) );
 414     return ret;
 415 }
 416
 417
 418 /***********************************************************************
 419  *             OpenFileMappingA   (KERNEL32.@)
 420  *
 421  * Opens a named file-mapping object.
 422  *
 423  * PARAMS
 424  *  access  [I] Access mode.
 425  *  inherit [I] Inherit flag.
 426  *  name    [I] Name of file-mapping object.
 427  *
 428  * RETURNS
 429  *      Success: Handle.
 430  *      Failure: NULL.
 431  */
 432 HANDLE WINAPI OpenFileMappingA( DWORD access, BOOL inherit, LPCSTR name )
 433 {
 434     WCHAR buffer[MAX_PATH];
 435
 436     if (!name) return OpenFileMappingW( access, inherit, NULL );
 437
 438     if (!MultiByteToWideChar( CP_ACP, 0, name, -1, buffer, MAX_PATH ))
 439     {
 440         SetLastError( ERROR_FILENAME_EXCED_RANGE );
 441         return 0;
 442     }
 443     return OpenFileMappingW( access, inherit, buffer );
 444 }
 445
 446
 447 /***********************************************************************
 448  *             OpenFileMappingW   (KERNEL32.@)
 449  *
 450  * See OpenFileMappingA.
 451  */
 452 HANDLE WINAPI OpenFileMappingW( DWORD access, BOOL inherit, LPCWSTR name)
 453 {
 454     OBJECT_ATTRIBUTES attr;
 455     UNICODE_STRING nameW;
 456     HANDLE ret;
 457     NTSTATUS status;
 458
 459     if (!name)
 460     {
 461         SetLastError( ERROR_INVALID_PARAMETER );
 462         return 0;
 463     }
 464     attr.Length = sizeof(attr);
 465     attr.RootDirectory = get_BaseNamedObjects_handle();
 466     attr.ObjectName = &nameW;
 467     attr.Attributes = inherit ? OBJ_INHERIT : 0;
 468     attr.SecurityDescriptor = NULL;
 469     attr.SecurityQualityOfService = NULL;
 470     RtlInitUnicodeString( &nameW, name );
 471
 472     if (access == FILE_MAP_COPY) access = SECTION_MAP_READ;
 473     access |= SECTION_QUERY;
 474
 475     if (GetVersion() & 0x80000000)
 476     {
 477         /* win9x doesn't do access checks, so try with full access first */
 478         if (!NtOpenSection( &ret, access | SECTION_MAP_READ | SECTION_MAP_WRITE, &attr )) return ret;
 479     }
 480
 481     if ((status = NtOpenSection( &ret, access, &attr )))
 482     {
 483         SetLastError( RtlNtStatusToDosError(status) );
 484         ret = 0;
 485     }
 486     return ret;
 487 }
 488
 489
 490 /***********************************************************************
 491  *             MapViewOfFile   (KERNEL32.@)
 492  *
 493  * Maps a view of a file into the address space.
 494  *
 495  * PARAMS
 496  *  mapping     [I] File-mapping object to map.
 497  *  access      [I] Access mode.
 498  *  offset_high [I] High-order 32 bits of file offset.
 499  *  offset_low  [I] Low-order 32 bits of file offset.
 500  *  count       [I] Number of bytes to map.
 501  *
 502  * RETURNS
 503  *      Success: Starting address of mapped view.
 504  *      Failure: NULL.
 505  */
 506 LPVOID WINAPI MapViewOfFile( HANDLE mapping, DWORD access,
 507     DWORD offset_high, DWORD offset_low, SIZE_T count )
 508 {
 509     return MapViewOfFileEx( mapping, access, offset_high,
 510                             offset_low, count, NULL );
 511 }
 512
 513
 514 /***********************************************************************
 515  *             MapViewOfFileEx   (KERNEL32.@)
 516  *
 517  * Maps a view of a file into the address space.
 518  *
 519  * PARAMS
 520  *  handle      [I] File-mapping object to map.
 521  *  access      [I] Access mode.
 522  *  offset_high [I] High-order 32 bits of file offset.
 523  *  offset_low  [I] Low-order 32 bits of file offset.
 524  *  count       [I] Number of bytes to map.
 525  *  addr        [I] Suggested starting address for mapped view.
 526  *
 527  * RETURNS
 528  *      Success: Starting address of mapped view.
 529  *      Failure: NULL.
 530  */
 531 LPVOID WINAPI MapViewOfFileEx( HANDLE handle, DWORD access,
 532     DWORD offset_high, DWORD offset_low, SIZE_T count, LPVOID addr )
 533 {
 534     NTSTATUS status;
 535     LARGE_INTEGER offset;
 536     ULONG protect;
 537
 538     offset.u.LowPart  = offset_low;
 539     offset.u.HighPart = offset_high;
 540
 541     if (access & FILE_MAP_WRITE) protect = PAGE_READWRITE;
 542     else if (access & FILE_MAP_COPY) protect = PAGE_WRITECOPY;
 543     else protect = PAGE_READONLY;
 544
 545     if (access & FILE_MAP_EXECUTE) protect <<= 4;
 546
 547     if ((status = NtMapViewOfSection( handle, GetCurrentProcess(), &addr, 0, 0, &offset,
 548                                       &count, ViewShare, 0, protect )))
 549     {
 550         SetLastError( RtlNtStatusToDosError(status) );
 551         addr = NULL;
 552     }
 553     return addr;
 554 }
 555
 556
 557 /***********************************************************************
 558  *             UnmapViewOfFile   (KERNEL32.@)
 559  *
 560  * Unmaps a mapped view of a file.
 561  *
 562  * PARAMS
 563  *  addr [I] Address where mapped view begins.
 564  *
 565  * RETURNS
 566  *      Success: TRUE.
 567  *      Failure: FALSE.
 568  *
 569  */
 570 BOOL WINAPI UnmapViewOfFile( LPCVOID addr )
 571 {
 572     NTSTATUS status = NtUnmapViewOfSection( GetCurrentProcess(), (void *)addr );
 573     if (status) SetLastError( RtlNtStatusToDosError(status) );
 574     return !status;
 575 }
 576
 577
 578 /***********************************************************************
 579  *             FlushViewOfFile   (KERNEL32.@)
 580  *
 581  * Writes to the disk a byte range within a mapped view of a file.
 582  *
 583  * PARAMS
 584  *  base [I] Start address of byte range to flush.
 585  *  size [I] Number of bytes in range.
 586  *
 587  * RETURNS
 588  *      Success: TRUE.
 589  *      Failure: FALSE.
 590  */
 591 BOOL WINAPI FlushViewOfFile( LPCVOID base, SIZE_T size )
 592 {
 593     NTSTATUS status = NtFlushVirtualMemory( GetCurrentProcess(), &base, &size, 0 );
 594     if (status)
 595     {
 596         if (status == STATUS_NOT_MAPPED_DATA) status = STATUS_SUCCESS;
 597         else SetLastError( RtlNtStatusToDosError(status) );
 598     }
 599     return !status;
 600 }
 601
 602
 603 /***********************************************************************
 604  *             GetWriteWatch   (KERNEL32.@)
 605  */
 606 UINT WINAPI GetWriteWatch( DWORD flags, LPVOID base, SIZE_T size, LPVOID *addresses,
 607                            ULONG_PTR *count, ULONG *granularity )
 608 {
 609     NTSTATUS status;
 610
 611     status = NtGetWriteWatch( GetCurrentProcess(), flags, base, size, addresses, count, granularity );
 612     if (status) SetLastError( RtlNtStatusToDosError(status) );
 613     return status ? ~0u : 0;
 614 }
 615
 616
 617 /***********************************************************************
 618  *             ResetWriteWatch   (KERNEL32.@)
 619  */
 620 UINT WINAPI ResetWriteWatch( LPVOID base, SIZE_T size )
 621 {
 622     NTSTATUS status;
 623
 624     status = NtResetWriteWatch( GetCurrentProcess(), base, size );
 625     if (status) SetLastError( RtlNtStatusToDosError(status) );
 626     return status ? ~0u : 0;
 627 }
 628
 629
 630 /***********************************************************************
 631  *             IsBadReadPtr   (KERNEL32.@)
 632  *
 633  * Check for read access on a memory block.
 634  *
 635  * ptr  [I] Address of memory block.
 636  * size [I] Size of block.
 637  *
 638  * RETURNS
 639  *  Success: TRUE.
 640  *      Failure: FALSE. Process has read access to entire block.
 641  */
 642 BOOL WINAPI IsBadReadPtr( LPCVOID ptr, UINT size )
 643 {
 644     if (!size) return FALSE;  /* handle 0 size case w/o reference */
 645     if (!ptr) return TRUE;
 646
 647     if (!page_size) page_size = getpagesize();
 648     __TRY
 649     {
 650         volatile const char *p = ptr;
 651         char dummy;
 652         UINT count = size;
 653
 654         while (count > page_size)
 655         {
 656             dummy = *p;
 657             p += page_size;
 658             count -= page_size;
 659         }
 660         dummy = p[0];
 661         dummy = p[count - 1];
 662     }
 663     __EXCEPT_PAGE_FAULT
 664     {
 665         TRACE_(seh)("%p caused page fault during read\n", ptr);
 666         return TRUE;
 667     }
 668     __ENDTRY
 669     return FALSE;
 670 }
 671
 672
 673 /***********************************************************************
 674  *             IsBadWritePtr   (KERNEL32.@)
 675  *
 676  * Check for write access on a memory block.
 677  *
 678  * PARAMS
 679  *  ptr  [I] Address of memory block.
 680  *  size [I] Size of block in bytes.
 681  *
 682  * RETURNS
 683  *  Success: TRUE.
 684  *      Failure: FALSE. Process has write access to entire block.
 685  */
 686 BOOL WINAPI IsBadWritePtr( LPVOID ptr, UINT size )
 687 {
 688     if (!size) return FALSE;  /* handle 0 size case w/o reference */
 689     if (!ptr) return TRUE;
 690
 691     if (!page_size) page_size = getpagesize();
 692     __TRY
 693     {
 694         volatile char *p = ptr;
 695         UINT count = size;
 696
 697         while (count > page_size)
 698         {
 699             *p |= 0;
 700             p += page_size;
 701             count -= page_size;
 702         }
 703         p[0] |= 0;
 704         p[count - 1] |= 0;
 705     }
 706     __EXCEPT_PAGE_FAULT
 707     {
 708         TRACE_(seh)("%p caused page fault during write\n", ptr);
 709         return TRUE;
 710     }
 711     __ENDTRY
 712     return FALSE;
 713 }
 714
 715
 716 /***********************************************************************
 717  *             IsBadHugeReadPtr   (KERNEL32.@)
 718  *
 719  * Check for read access on a memory block.
 720  *
 721  * PARAMS
 722  *  ptr  [I] Address of memory block.
 723  *  size [I] Size of block.
 724  *
 725  * RETURNS
 726  *  Success: TRUE.
 727  *      Failure: FALSE. Process has read access to entire block.
 728  */
 729 BOOL WINAPI IsBadHugeReadPtr( LPCVOID ptr, UINT size )
 730 {
 731     return IsBadReadPtr( ptr, size );
 732 }
 733
 734
 735 /***********************************************************************
 736  *             IsBadHugeWritePtr   (KERNEL32.@)
 737  *
 738  * Check for write access on a memory block.
 739  *
 740  * PARAMS
 741  *  ptr  [I] Address of memory block.
 742  *  size [I] Size of block.
 743  *
 744  * RETURNS
 745  *  Success: TRUE.
 746  *      Failure: FALSE. Process has write access to entire block.
 747  */
 748 BOOL WINAPI IsBadHugeWritePtr( LPVOID ptr, UINT size )
 749 {
 750     return IsBadWritePtr( ptr, size );
 751 }
 752
 753
 754 /***********************************************************************
 755  *             IsBadCodePtr   (KERNEL32.@)
 756  *
 757  * Check for read access on a memory address.
 758  *
 759  * PARAMS
 760  *  ptr [I] Address of function.
 761  *
 762  * RETURNS
 763  *      Success: TRUE.
 764  *      Failure: FALSE. Process has read access to specified memory.
 765  */
 766 BOOL WINAPI IsBadCodePtr( FARPROC ptr )
 767 {
 768     return IsBadReadPtr( ptr, 1 );
 769 }
 770
 771
 772 /***********************************************************************
 773  *             IsBadStringPtrA   (KERNEL32.@)
 774  *
 775  * Check for read access on a range of memory pointed to by a string pointer.
 776  *
 777  * PARAMS
 778  *  str [I] Address of string.
 779  *  max [I] Maximum size of string.
 780  *
 781  * RETURNS
 782  *      Success: TRUE.
 783  *      Failure: FALSE. Read access to all bytes in string.
 784  */
 785 BOOL WINAPI IsBadStringPtrA( LPCSTR str, UINT max )
 786 {
 787     if (!str) return TRUE;
 788
 789     __TRY
 790     {
 791         volatile const char *p = str;
 792         while (p != str + max) if (!*p++) break;
 793     }
 794     __EXCEPT_PAGE_FAULT
 795     {
 796         TRACE_(seh)("%p caused page fault during read\n", str);
 797         return TRUE;
 798     }
 799     __ENDTRY
 800     return FALSE;
 801 }
 802
 803
 804 /***********************************************************************
 805  *             IsBadStringPtrW   (KERNEL32.@)
 806  *
 807  * See IsBadStringPtrA.
 808  */
 809 BOOL WINAPI IsBadStringPtrW( LPCWSTR str, UINT max )
 810 {
 811     if (!str) return TRUE;
 812
 813     __TRY
 814     {
 815         volatile const WCHAR *p = str;
 816         while (p != str + max) if (!*p++) break;
 817     }
 818     __EXCEPT_PAGE_FAULT
 819     {
 820         TRACE_(seh)("%p caused page fault during read\n", str);
 821         return TRUE;
 822     }
 823     __ENDTRY
 824     return FALSE;
 825 }