xref: /sqlite-3.40.0/src/os_win.c (revision 2e27d28f)
1 /*
2 ** 2004 May 22
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 ******************************************************************************
12 **
13 ** This file contains code that is specific to Windows.
14 */
15 #include "sqliteInt.h"
16 #if SQLITE_OS_WIN               /* This file is used for Windows only */
17 
18 /*
19 ** Include code that is common to all os_*.c files
20 */
21 #include "os_common.h"
22 
23 /*
24 ** Include the header file for the Windows VFS.
25 */
26 #include "os_win.h"
27 
28 /*
29 ** Compiling and using WAL mode requires several APIs that are only
30 ** available in Windows platforms based on the NT kernel.
31 */
32 #if !SQLITE_OS_WINNT && !defined(SQLITE_OMIT_WAL)
33 #  error "WAL mode requires support from the Windows NT kernel, compile\
34  with SQLITE_OMIT_WAL."
35 #endif
36 
37 #if !SQLITE_OS_WINNT && SQLITE_MAX_MMAP_SIZE>0
38 #  error "Memory mapped files require support from the Windows NT kernel,\
39  compile with SQLITE_MAX_MMAP_SIZE=0."
40 #endif
41 
42 /*
43 ** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
44 ** based on the sub-platform)?
45 */
46 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(SQLITE_WIN32_NO_ANSI)
47 #  define SQLITE_WIN32_HAS_ANSI
48 #endif
49 
50 /*
51 ** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
52 ** based on the sub-platform)?
53 */
54 #if (SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT) && \
55     !defined(SQLITE_WIN32_NO_WIDE)
56 #  define SQLITE_WIN32_HAS_WIDE
57 #endif
58 
59 /*
60 ** Make sure at least one set of Win32 APIs is available.
61 */
62 #if !defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_WIN32_HAS_WIDE)
63 #  error "At least one of SQLITE_WIN32_HAS_ANSI and SQLITE_WIN32_HAS_WIDE\
64  must be defined."
65 #endif
66 
67 /*
68 ** Define the required Windows SDK version constants if they are not
69 ** already available.
70 */
71 #ifndef NTDDI_WIN8
72 #  define NTDDI_WIN8                        0x06020000
73 #endif
74 
75 #ifndef NTDDI_WINBLUE
76 #  define NTDDI_WINBLUE                     0x06030000
77 #endif
78 
79 #ifndef NTDDI_WINTHRESHOLD
80 #  define NTDDI_WINTHRESHOLD                0x06040000
81 #endif
82 
83 /*
84 ** Check to see if the GetVersionEx[AW] functions are deprecated on the
85 ** target system.  GetVersionEx was first deprecated in Win8.1.
86 */
87 #ifndef SQLITE_WIN32_GETVERSIONEX
88 #  if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WINBLUE
89 #    define SQLITE_WIN32_GETVERSIONEX   0   /* GetVersionEx() is deprecated */
90 #  else
91 #    define SQLITE_WIN32_GETVERSIONEX   1   /* GetVersionEx() is current */
92 #  endif
93 #endif
94 
95 /*
96 ** Check to see if the CreateFileMappingA function is supported on the
97 ** target system.  It is unavailable when using "mincore.lib" on Win10.
98 ** When compiling for Windows 10, always assume "mincore.lib" is in use.
99 */
100 #ifndef SQLITE_WIN32_CREATEFILEMAPPINGA
101 #  if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WINTHRESHOLD
102 #    define SQLITE_WIN32_CREATEFILEMAPPINGA   0
103 #  else
104 #    define SQLITE_WIN32_CREATEFILEMAPPINGA   1
105 #  endif
106 #endif
107 
108 /*
109 ** This constant should already be defined (in the "WinDef.h" SDK file).
110 */
111 #ifndef MAX_PATH
112 #  define MAX_PATH                      (260)
113 #endif
114 
115 /*
116 ** Maximum pathname length (in chars) for Win32.  This should normally be
117 ** MAX_PATH.
118 */
119 #ifndef SQLITE_WIN32_MAX_PATH_CHARS
120 #  define SQLITE_WIN32_MAX_PATH_CHARS   (MAX_PATH)
121 #endif
122 
123 /*
124 ** This constant should already be defined (in the "WinNT.h" SDK file).
125 */
126 #ifndef UNICODE_STRING_MAX_CHARS
127 #  define UNICODE_STRING_MAX_CHARS      (32767)
128 #endif
129 
130 /*
131 ** Maximum pathname length (in chars) for WinNT.  This should normally be
132 ** UNICODE_STRING_MAX_CHARS.
133 */
134 #ifndef SQLITE_WINNT_MAX_PATH_CHARS
135 #  define SQLITE_WINNT_MAX_PATH_CHARS   (UNICODE_STRING_MAX_CHARS)
136 #endif
137 
138 /*
139 ** Maximum pathname length (in bytes) for Win32.  The MAX_PATH macro is in
140 ** characters, so we allocate 4 bytes per character assuming worst-case of
141 ** 4-bytes-per-character for UTF8.
142 */
143 #ifndef SQLITE_WIN32_MAX_PATH_BYTES
144 #  define SQLITE_WIN32_MAX_PATH_BYTES   (SQLITE_WIN32_MAX_PATH_CHARS*4)
145 #endif
146 
147 /*
148 ** Maximum pathname length (in bytes) for WinNT.  This should normally be
149 ** UNICODE_STRING_MAX_CHARS * sizeof(WCHAR).
150 */
151 #ifndef SQLITE_WINNT_MAX_PATH_BYTES
152 #  define SQLITE_WINNT_MAX_PATH_BYTES   \
153                             (sizeof(WCHAR) * SQLITE_WINNT_MAX_PATH_CHARS)
154 #endif
155 
156 /*
157 ** Maximum error message length (in chars) for WinRT.
158 */
159 #ifndef SQLITE_WIN32_MAX_ERRMSG_CHARS
160 #  define SQLITE_WIN32_MAX_ERRMSG_CHARS (1024)
161 #endif
162 
163 /*
164 ** Returns non-zero if the character should be treated as a directory
165 ** separator.
166 */
167 #ifndef winIsDirSep
168 #  define winIsDirSep(a)                (((a) == '/') || ((a) == '\\'))
169 #endif
170 
171 /*
172 ** This macro is used when a local variable is set to a value that is
173 ** [sometimes] not used by the code (e.g. via conditional compilation).
174 */
175 #ifndef UNUSED_VARIABLE_VALUE
176 #  define UNUSED_VARIABLE_VALUE(x)      (void)(x)
177 #endif
178 
179 /*
180 ** Returns the character that should be used as the directory separator.
181 */
182 #ifndef winGetDirSep
183 #  define winGetDirSep()                '\\'
184 #endif
185 
186 /*
187 ** Do we need to manually define the Win32 file mapping APIs for use with WAL
188 ** mode or memory mapped files (e.g. these APIs are available in the Windows
189 ** CE SDK; however, they are not present in the header file)?
190 */
191 #if SQLITE_WIN32_FILEMAPPING_API && \
192         (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
193 /*
194 ** Two of the file mapping APIs are different under WinRT.  Figure out which
195 ** set we need.
196 */
197 #if SQLITE_OS_WINRT
198 WINBASEAPI HANDLE WINAPI CreateFileMappingFromApp(HANDLE, \
199         LPSECURITY_ATTRIBUTES, ULONG, ULONG64, LPCWSTR);
200 
201 WINBASEAPI LPVOID WINAPI MapViewOfFileFromApp(HANDLE, ULONG, ULONG64, SIZE_T);
202 #else
203 #if defined(SQLITE_WIN32_HAS_ANSI)
204 WINBASEAPI HANDLE WINAPI CreateFileMappingA(HANDLE, LPSECURITY_ATTRIBUTES, \
205         DWORD, DWORD, DWORD, LPCSTR);
206 #endif /* defined(SQLITE_WIN32_HAS_ANSI) */
207 
208 #if defined(SQLITE_WIN32_HAS_WIDE)
209 WINBASEAPI HANDLE WINAPI CreateFileMappingW(HANDLE, LPSECURITY_ATTRIBUTES, \
210         DWORD, DWORD, DWORD, LPCWSTR);
211 #endif /* defined(SQLITE_WIN32_HAS_WIDE) */
212 
213 WINBASEAPI LPVOID WINAPI MapViewOfFile(HANDLE, DWORD, DWORD, DWORD, SIZE_T);
214 #endif /* SQLITE_OS_WINRT */
215 
216 /*
217 ** These file mapping APIs are common to both Win32 and WinRT.
218 */
219 
220 WINBASEAPI BOOL WINAPI FlushViewOfFile(LPCVOID, SIZE_T);
221 WINBASEAPI BOOL WINAPI UnmapViewOfFile(LPCVOID);
222 #endif /* SQLITE_WIN32_FILEMAPPING_API */
223 
224 /*
225 ** Some Microsoft compilers lack this definition.
226 */
227 #ifndef INVALID_FILE_ATTRIBUTES
228 # define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
229 #endif
230 
231 #ifndef FILE_FLAG_MASK
232 # define FILE_FLAG_MASK          (0xFF3C0000)
233 #endif
234 
235 #ifndef FILE_ATTRIBUTE_MASK
236 # define FILE_ATTRIBUTE_MASK     (0x0003FFF7)
237 #endif
238 
239 #ifndef SQLITE_OMIT_WAL
240 /* Forward references to structures used for WAL */
241 typedef struct winShm winShm;           /* A connection to shared-memory */
242 typedef struct winShmNode winShmNode;   /* A region of shared-memory */
243 #endif
244 
245 /*
246 ** WinCE lacks native support for file locking so we have to fake it
247 ** with some code of our own.
248 */
249 #if SQLITE_OS_WINCE
250 typedef struct winceLock {
251   int nReaders;       /* Number of reader locks obtained */
252   BOOL bPending;      /* Indicates a pending lock has been obtained */
253   BOOL bReserved;     /* Indicates a reserved lock has been obtained */
254   BOOL bExclusive;    /* Indicates an exclusive lock has been obtained */
255 } winceLock;
256 #endif
257 
258 /*
259 ** The winFile structure is a subclass of sqlite3_file* specific to the win32
260 ** portability layer.
261 */
262 typedef struct winFile winFile;
263 struct winFile {
264   const sqlite3_io_methods *pMethod; /*** Must be first ***/
265   sqlite3_vfs *pVfs;      /* The VFS used to open this file */
266   HANDLE h;               /* Handle for accessing the file */
267   u8 locktype;            /* Type of lock currently held on this file */
268   short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
269   u8 ctrlFlags;           /* Flags.  See WINFILE_* below */
270   DWORD lastErrno;        /* The Windows errno from the last I/O error */
271 #ifndef SQLITE_OMIT_WAL
272   winShm *pShm;           /* Instance of shared memory on this file */
273 #endif
274   const char *zPath;      /* Full pathname of this file */
275   int szChunk;            /* Chunk size configured by FCNTL_CHUNK_SIZE */
276 #if SQLITE_OS_WINCE
277   LPWSTR zDeleteOnClose;  /* Name of file to delete when closing */
278   HANDLE hMutex;          /* Mutex used to control access to shared lock */
279   HANDLE hShared;         /* Shared memory segment used for locking */
280   winceLock local;        /* Locks obtained by this instance of winFile */
281   winceLock *shared;      /* Global shared lock memory for the file  */
282 #endif
283 #if SQLITE_MAX_MMAP_SIZE>0
284   int nFetchOut;                /* Number of outstanding xFetch references */
285   HANDLE hMap;                  /* Handle for accessing memory mapping */
286   void *pMapRegion;             /* Area memory mapped */
287   sqlite3_int64 mmapSize;       /* Usable size of mapped region */
288   sqlite3_int64 mmapSizeActual; /* Actual size of mapped region */
289   sqlite3_int64 mmapSizeMax;    /* Configured FCNTL_MMAP_SIZE value */
290 #endif
291 };
292 
293 /*
294 ** The winVfsAppData structure is used for the pAppData member for all of the
295 ** Win32 VFS variants.
296 */
297 typedef struct winVfsAppData winVfsAppData;
298 struct winVfsAppData {
299   const sqlite3_io_methods *pMethod; /* The file I/O methods to use. */
300   void *pAppData;                    /* The extra pAppData, if any. */
301   BOOL bNoLock;                      /* Non-zero if locking is disabled. */
302 };
303 
304 /*
305 ** Allowed values for winFile.ctrlFlags
306 */
307 #define WINFILE_RDONLY          0x02   /* Connection is read only */
308 #define WINFILE_PERSIST_WAL     0x04   /* Persistent WAL mode */
309 #define WINFILE_PSOW            0x10   /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
310 
311 /*
312  * The size of the buffer used by sqlite3_win32_write_debug().
313  */
314 #ifndef SQLITE_WIN32_DBG_BUF_SIZE
315 #  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
316 #endif
317 
318 /*
319  * The value used with sqlite3_win32_set_directory() to specify that
320  * the data directory should be changed.
321  */
322 #ifndef SQLITE_WIN32_DATA_DIRECTORY_TYPE
323 #  define SQLITE_WIN32_DATA_DIRECTORY_TYPE (1)
324 #endif
325 
326 /*
327  * The value used with sqlite3_win32_set_directory() to specify that
328  * the temporary directory should be changed.
329  */
330 #ifndef SQLITE_WIN32_TEMP_DIRECTORY_TYPE
331 #  define SQLITE_WIN32_TEMP_DIRECTORY_TYPE (2)
332 #endif
333 
334 /*
335  * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
336  * various Win32 API heap functions instead of our own.
337  */
338 #ifdef SQLITE_WIN32_MALLOC
339 
340 /*
341  * If this is non-zero, an isolated heap will be created by the native Win32
342  * allocator subsystem; otherwise, the default process heap will be used.  This
343  * setting has no effect when compiling for WinRT.  By default, this is enabled
344  * and an isolated heap will be created to store all allocated data.
345  *
346  ******************************************************************************
347  * WARNING: It is important to note that when this setting is non-zero and the
348  *          winMemShutdown function is called (e.g. by the sqlite3_shutdown
349  *          function), all data that was allocated using the isolated heap will
350  *          be freed immediately and any attempt to access any of that freed
351  *          data will almost certainly result in an immediate access violation.
352  ******************************************************************************
353  */
354 #ifndef SQLITE_WIN32_HEAP_CREATE
355 #  define SQLITE_WIN32_HEAP_CREATE        (TRUE)
356 #endif
357 
358 /*
359  * This is the maximum possible initial size of the Win32-specific heap, in
360  * bytes.
361  */
362 #ifndef SQLITE_WIN32_HEAP_MAX_INIT_SIZE
363 #  define SQLITE_WIN32_HEAP_MAX_INIT_SIZE (4294967295U)
364 #endif
365 
366 /*
367  * This is the extra space for the initial size of the Win32-specific heap,
368  * in bytes.  This value may be zero.
369  */
370 #ifndef SQLITE_WIN32_HEAP_INIT_EXTRA
371 #  define SQLITE_WIN32_HEAP_INIT_EXTRA  (4194304)
372 #endif
373 
374 /*
375  * Calculate the maximum legal cache size, in pages, based on the maximum
376  * possible initial heap size and the default page size, setting aside the
377  * needed extra space.
378  */
379 #ifndef SQLITE_WIN32_MAX_CACHE_SIZE
380 #  define SQLITE_WIN32_MAX_CACHE_SIZE   (((SQLITE_WIN32_HEAP_MAX_INIT_SIZE) - \
381                                           (SQLITE_WIN32_HEAP_INIT_EXTRA)) / \
382                                          (SQLITE_DEFAULT_PAGE_SIZE))
383 #endif
384 
385 /*
386  * This is cache size used in the calculation of the initial size of the
387  * Win32-specific heap.  It cannot be negative.
388  */
389 #ifndef SQLITE_WIN32_CACHE_SIZE
390 #  if SQLITE_DEFAULT_CACHE_SIZE>=0
391 #    define SQLITE_WIN32_CACHE_SIZE     (SQLITE_DEFAULT_CACHE_SIZE)
392 #  else
393 #    define SQLITE_WIN32_CACHE_SIZE     (-(SQLITE_DEFAULT_CACHE_SIZE))
394 #  endif
395 #endif
396 
397 /*
398  * Make sure that the calculated cache size, in pages, cannot cause the
399  * initial size of the Win32-specific heap to exceed the maximum amount
400  * of memory that can be specified in the call to HeapCreate.
401  */
402 #if SQLITE_WIN32_CACHE_SIZE>SQLITE_WIN32_MAX_CACHE_SIZE
403 #  undef SQLITE_WIN32_CACHE_SIZE
404 #  define SQLITE_WIN32_CACHE_SIZE       (2000)
405 #endif
406 
407 /*
408  * The initial size of the Win32-specific heap.  This value may be zero.
409  */
410 #ifndef SQLITE_WIN32_HEAP_INIT_SIZE
411 #  define SQLITE_WIN32_HEAP_INIT_SIZE   ((SQLITE_WIN32_CACHE_SIZE) * \
412                                          (SQLITE_DEFAULT_PAGE_SIZE) + \
413                                          (SQLITE_WIN32_HEAP_INIT_EXTRA))
414 #endif
415 
416 /*
417  * The maximum size of the Win32-specific heap.  This value may be zero.
418  */
419 #ifndef SQLITE_WIN32_HEAP_MAX_SIZE
420 #  define SQLITE_WIN32_HEAP_MAX_SIZE    (0)
421 #endif
422 
423 /*
424  * The extra flags to use in calls to the Win32 heap APIs.  This value may be
425  * zero for the default behavior.
426  */
427 #ifndef SQLITE_WIN32_HEAP_FLAGS
428 #  define SQLITE_WIN32_HEAP_FLAGS       (0)
429 #endif
430 
431 
432 /*
433 ** The winMemData structure stores information required by the Win32-specific
434 ** sqlite3_mem_methods implementation.
435 */
436 typedef struct winMemData winMemData;
437 struct winMemData {
438 #ifndef NDEBUG
439   u32 magic1;   /* Magic number to detect structure corruption. */
440 #endif
441   HANDLE hHeap; /* The handle to our heap. */
442   BOOL bOwned;  /* Do we own the heap (i.e. destroy it on shutdown)? */
443 #ifndef NDEBUG
444   u32 magic2;   /* Magic number to detect structure corruption. */
445 #endif
446 };
447 
448 #ifndef NDEBUG
449 #define WINMEM_MAGIC1     0x42b2830b
450 #define WINMEM_MAGIC2     0xbd4d7cf4
451 #endif
452 
453 static struct winMemData win_mem_data = {
454 #ifndef NDEBUG
455   WINMEM_MAGIC1,
456 #endif
457   NULL, FALSE
458 #ifndef NDEBUG
459   ,WINMEM_MAGIC2
460 #endif
461 };
462 
463 #ifndef NDEBUG
464 #define winMemAssertMagic1() assert( win_mem_data.magic1==WINMEM_MAGIC1 )
465 #define winMemAssertMagic2() assert( win_mem_data.magic2==WINMEM_MAGIC2 )
466 #define winMemAssertMagic()  winMemAssertMagic1(); winMemAssertMagic2();
467 #else
468 #define winMemAssertMagic()
469 #endif
470 
471 #define winMemGetDataPtr()  &win_mem_data
472 #define winMemGetHeap()     win_mem_data.hHeap
473 #define winMemGetOwned()    win_mem_data.bOwned
474 
475 static void *winMemMalloc(int nBytes);
476 static void winMemFree(void *pPrior);
477 static void *winMemRealloc(void *pPrior, int nBytes);
478 static int winMemSize(void *p);
479 static int winMemRoundup(int n);
480 static int winMemInit(void *pAppData);
481 static void winMemShutdown(void *pAppData);
482 
483 const sqlite3_mem_methods *sqlite3MemGetWin32(void);
484 #endif /* SQLITE_WIN32_MALLOC */
485 
486 /*
487 ** The following variable is (normally) set once and never changes
488 ** thereafter.  It records whether the operating system is Win9x
489 ** or WinNT.
490 **
491 ** 0:   Operating system unknown.
492 ** 1:   Operating system is Win9x.
493 ** 2:   Operating system is WinNT.
494 **
495 ** In order to facilitate testing on a WinNT system, the test fixture
496 ** can manually set this value to 1 to emulate Win98 behavior.
497 */
498 #ifdef SQLITE_TEST
499 LONG SQLITE_WIN32_VOLATILE sqlite3_os_type = 0;
500 #else
501 static LONG SQLITE_WIN32_VOLATILE sqlite3_os_type = 0;
502 #endif
503 
504 #ifndef SYSCALL
505 #  define SYSCALL sqlite3_syscall_ptr
506 #endif
507 
508 /*
509 ** This function is not available on Windows CE or WinRT.
510  */
511 
512 #if SQLITE_OS_WINCE || SQLITE_OS_WINRT
513 #  define osAreFileApisANSI()       1
514 #endif
515 
516 /*
517 ** Many system calls are accessed through pointer-to-functions so that
518 ** they may be overridden at runtime to facilitate fault injection during
519 ** testing and sandboxing.  The following array holds the names and pointers
520 ** to all overrideable system calls.
521 */
522 static struct win_syscall {
523   const char *zName;            /* Name of the system call */
524   sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
525   sqlite3_syscall_ptr pDefault; /* Default value */
526 } aSyscall[] = {
527 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
528   { "AreFileApisANSI",         (SYSCALL)AreFileApisANSI,         0 },
529 #else
530   { "AreFileApisANSI",         (SYSCALL)0,                       0 },
531 #endif
532 
533 #ifndef osAreFileApisANSI
534 #define osAreFileApisANSI ((BOOL(WINAPI*)(VOID))aSyscall[0].pCurrent)
535 #endif
536 
537 #if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
538   { "CharLowerW",              (SYSCALL)CharLowerW,              0 },
539 #else
540   { "CharLowerW",              (SYSCALL)0,                       0 },
541 #endif
542 
543 #define osCharLowerW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[1].pCurrent)
544 
545 #if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
546   { "CharUpperW",              (SYSCALL)CharUpperW,              0 },
547 #else
548   { "CharUpperW",              (SYSCALL)0,                       0 },
549 #endif
550 
551 #define osCharUpperW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[2].pCurrent)
552 
553   { "CloseHandle",             (SYSCALL)CloseHandle,             0 },
554 
555 #define osCloseHandle ((BOOL(WINAPI*)(HANDLE))aSyscall[3].pCurrent)
556 
557 #if defined(SQLITE_WIN32_HAS_ANSI)
558   { "CreateFileA",             (SYSCALL)CreateFileA,             0 },
559 #else
560   { "CreateFileA",             (SYSCALL)0,                       0 },
561 #endif
562 
563 #define osCreateFileA ((HANDLE(WINAPI*)(LPCSTR,DWORD,DWORD, \
564         LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[4].pCurrent)
565 
566 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
567   { "CreateFileW",             (SYSCALL)CreateFileW,             0 },
568 #else
569   { "CreateFileW",             (SYSCALL)0,                       0 },
570 #endif
571 
572 #define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
573         LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)
574 
575 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_ANSI) && \
576         (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0) && \
577         SQLITE_WIN32_CREATEFILEMAPPINGA
578   { "CreateFileMappingA",      (SYSCALL)CreateFileMappingA,      0 },
579 #else
580   { "CreateFileMappingA",      (SYSCALL)0,                       0 },
581 #endif
582 
583 #define osCreateFileMappingA ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
584         DWORD,DWORD,DWORD,LPCSTR))aSyscall[6].pCurrent)
585 
586 #if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
587         (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0))
588   { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
589 #else
590   { "CreateFileMappingW",      (SYSCALL)0,                       0 },
591 #endif
592 
593 #define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
594         DWORD,DWORD,DWORD,LPCWSTR))aSyscall[7].pCurrent)
595 
596 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
597   { "CreateMutexW",            (SYSCALL)CreateMutexW,            0 },
598 #else
599   { "CreateMutexW",            (SYSCALL)0,                       0 },
600 #endif
601 
602 #define osCreateMutexW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,BOOL, \
603         LPCWSTR))aSyscall[8].pCurrent)
604 
605 #if defined(SQLITE_WIN32_HAS_ANSI)
606   { "DeleteFileA",             (SYSCALL)DeleteFileA,             0 },
607 #else
608   { "DeleteFileA",             (SYSCALL)0,                       0 },
609 #endif
610 
611 #define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[9].pCurrent)
612 
613 #if defined(SQLITE_WIN32_HAS_WIDE)
614   { "DeleteFileW",             (SYSCALL)DeleteFileW,             0 },
615 #else
616   { "DeleteFileW",             (SYSCALL)0,                       0 },
617 #endif
618 
619 #define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[10].pCurrent)
620 
621 #if SQLITE_OS_WINCE
622   { "FileTimeToLocalFileTime", (SYSCALL)FileTimeToLocalFileTime, 0 },
623 #else
624   { "FileTimeToLocalFileTime", (SYSCALL)0,                       0 },
625 #endif
626 
627 #define osFileTimeToLocalFileTime ((BOOL(WINAPI*)(CONST FILETIME*, \
628         LPFILETIME))aSyscall[11].pCurrent)
629 
630 #if SQLITE_OS_WINCE
631   { "FileTimeToSystemTime",    (SYSCALL)FileTimeToSystemTime,    0 },
632 #else
633   { "FileTimeToSystemTime",    (SYSCALL)0,                       0 },
634 #endif
635 
636 #define osFileTimeToSystemTime ((BOOL(WINAPI*)(CONST FILETIME*, \
637         LPSYSTEMTIME))aSyscall[12].pCurrent)
638 
639   { "FlushFileBuffers",        (SYSCALL)FlushFileBuffers,        0 },
640 
641 #define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[13].pCurrent)
642 
643 #if defined(SQLITE_WIN32_HAS_ANSI)
644   { "FormatMessageA",          (SYSCALL)FormatMessageA,          0 },
645 #else
646   { "FormatMessageA",          (SYSCALL)0,                       0 },
647 #endif
648 
649 #define osFormatMessageA ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPSTR, \
650         DWORD,va_list*))aSyscall[14].pCurrent)
651 
652 #if defined(SQLITE_WIN32_HAS_WIDE)
653   { "FormatMessageW",          (SYSCALL)FormatMessageW,          0 },
654 #else
655   { "FormatMessageW",          (SYSCALL)0,                       0 },
656 #endif
657 
658 #define osFormatMessageW ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPWSTR, \
659         DWORD,va_list*))aSyscall[15].pCurrent)
660 
661 #if !defined(SQLITE_OMIT_LOAD_EXTENSION)
662   { "FreeLibrary",             (SYSCALL)FreeLibrary,             0 },
663 #else
664   { "FreeLibrary",             (SYSCALL)0,                       0 },
665 #endif
666 
667 #define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[16].pCurrent)
668 
669   { "GetCurrentProcessId",     (SYSCALL)GetCurrentProcessId,     0 },
670 
671 #define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[17].pCurrent)
672 
673 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
674   { "GetDiskFreeSpaceA",       (SYSCALL)GetDiskFreeSpaceA,       0 },
675 #else
676   { "GetDiskFreeSpaceA",       (SYSCALL)0,                       0 },
677 #endif
678 
679 #define osGetDiskFreeSpaceA ((BOOL(WINAPI*)(LPCSTR,LPDWORD,LPDWORD,LPDWORD, \
680         LPDWORD))aSyscall[18].pCurrent)
681 
682 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
683   { "GetDiskFreeSpaceW",       (SYSCALL)GetDiskFreeSpaceW,       0 },
684 #else
685   { "GetDiskFreeSpaceW",       (SYSCALL)0,                       0 },
686 #endif
687 
688 #define osGetDiskFreeSpaceW ((BOOL(WINAPI*)(LPCWSTR,LPDWORD,LPDWORD,LPDWORD, \
689         LPDWORD))aSyscall[19].pCurrent)
690 
691 #if defined(SQLITE_WIN32_HAS_ANSI)
692   { "GetFileAttributesA",      (SYSCALL)GetFileAttributesA,      0 },
693 #else
694   { "GetFileAttributesA",      (SYSCALL)0,                       0 },
695 #endif
696 
697 #define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[20].pCurrent)
698 
699 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
700   { "GetFileAttributesW",      (SYSCALL)GetFileAttributesW,      0 },
701 #else
702   { "GetFileAttributesW",      (SYSCALL)0,                       0 },
703 #endif
704 
705 #define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[21].pCurrent)
706 
707 #if defined(SQLITE_WIN32_HAS_WIDE)
708   { "GetFileAttributesExW",    (SYSCALL)GetFileAttributesExW,    0 },
709 #else
710   { "GetFileAttributesExW",    (SYSCALL)0,                       0 },
711 #endif
712 
713 #define osGetFileAttributesExW ((BOOL(WINAPI*)(LPCWSTR,GET_FILEEX_INFO_LEVELS, \
714         LPVOID))aSyscall[22].pCurrent)
715 
716 #if !SQLITE_OS_WINRT
717   { "GetFileSize",             (SYSCALL)GetFileSize,             0 },
718 #else
719   { "GetFileSize",             (SYSCALL)0,                       0 },
720 #endif
721 
722 #define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[23].pCurrent)
723 
724 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
725   { "GetFullPathNameA",        (SYSCALL)GetFullPathNameA,        0 },
726 #else
727   { "GetFullPathNameA",        (SYSCALL)0,                       0 },
728 #endif
729 
730 #define osGetFullPathNameA ((DWORD(WINAPI*)(LPCSTR,DWORD,LPSTR, \
731         LPSTR*))aSyscall[24].pCurrent)
732 
733 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
734   { "GetFullPathNameW",        (SYSCALL)GetFullPathNameW,        0 },
735 #else
736   { "GetFullPathNameW",        (SYSCALL)0,                       0 },
737 #endif
738 
739 #define osGetFullPathNameW ((DWORD(WINAPI*)(LPCWSTR,DWORD,LPWSTR, \
740         LPWSTR*))aSyscall[25].pCurrent)
741 
742   { "GetLastError",            (SYSCALL)GetLastError,            0 },
743 
744 #define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[26].pCurrent)
745 
746 #if !defined(SQLITE_OMIT_LOAD_EXTENSION)
747 #if SQLITE_OS_WINCE
748   /* The GetProcAddressA() routine is only available on Windows CE. */
749   { "GetProcAddressA",         (SYSCALL)GetProcAddressA,         0 },
750 #else
751   /* All other Windows platforms expect GetProcAddress() to take
752   ** an ANSI string regardless of the _UNICODE setting */
753   { "GetProcAddressA",         (SYSCALL)GetProcAddress,          0 },
754 #endif
755 #else
756   { "GetProcAddressA",         (SYSCALL)0,                       0 },
757 #endif
758 
759 #define osGetProcAddressA ((FARPROC(WINAPI*)(HMODULE, \
760         LPCSTR))aSyscall[27].pCurrent)
761 
762 #if !SQLITE_OS_WINRT
763   { "GetSystemInfo",           (SYSCALL)GetSystemInfo,           0 },
764 #else
765   { "GetSystemInfo",           (SYSCALL)0,                       0 },
766 #endif
767 
768 #define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[28].pCurrent)
769 
770   { "GetSystemTime",           (SYSCALL)GetSystemTime,           0 },
771 
772 #define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[29].pCurrent)
773 
774 #if !SQLITE_OS_WINCE
775   { "GetSystemTimeAsFileTime", (SYSCALL)GetSystemTimeAsFileTime, 0 },
776 #else
777   { "GetSystemTimeAsFileTime", (SYSCALL)0,                       0 },
778 #endif
779 
780 #define osGetSystemTimeAsFileTime ((VOID(WINAPI*)( \
781         LPFILETIME))aSyscall[30].pCurrent)
782 
783 #if defined(SQLITE_WIN32_HAS_ANSI)
784   { "GetTempPathA",            (SYSCALL)GetTempPathA,            0 },
785 #else
786   { "GetTempPathA",            (SYSCALL)0,                       0 },
787 #endif
788 
789 #define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[31].pCurrent)
790 
791 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
792   { "GetTempPathW",            (SYSCALL)GetTempPathW,            0 },
793 #else
794   { "GetTempPathW",            (SYSCALL)0,                       0 },
795 #endif
796 
797 #define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[32].pCurrent)
798 
799 #if !SQLITE_OS_WINRT
800   { "GetTickCount",            (SYSCALL)GetTickCount,            0 },
801 #else
802   { "GetTickCount",            (SYSCALL)0,                       0 },
803 #endif
804 
805 #define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[33].pCurrent)
806 
807 #if defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_GETVERSIONEX
808   { "GetVersionExA",           (SYSCALL)GetVersionExA,           0 },
809 #else
810   { "GetVersionExA",           (SYSCALL)0,                       0 },
811 #endif
812 
813 #define osGetVersionExA ((BOOL(WINAPI*)( \
814         LPOSVERSIONINFOA))aSyscall[34].pCurrent)
815 
816 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
817         SQLITE_WIN32_GETVERSIONEX
818   { "GetVersionExW",           (SYSCALL)GetVersionExW,           0 },
819 #else
820   { "GetVersionExW",           (SYSCALL)0,                       0 },
821 #endif
822 
823 #define osGetVersionExW ((BOOL(WINAPI*)( \
824         LPOSVERSIONINFOW))aSyscall[35].pCurrent)
825 
826   { "HeapAlloc",               (SYSCALL)HeapAlloc,               0 },
827 
828 #define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
829         SIZE_T))aSyscall[36].pCurrent)
830 
831 #if !SQLITE_OS_WINRT
832   { "HeapCreate",              (SYSCALL)HeapCreate,              0 },
833 #else
834   { "HeapCreate",              (SYSCALL)0,                       0 },
835 #endif
836 
837 #define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
838         SIZE_T))aSyscall[37].pCurrent)
839 
840 #if !SQLITE_OS_WINRT
841   { "HeapDestroy",             (SYSCALL)HeapDestroy,             0 },
842 #else
843   { "HeapDestroy",             (SYSCALL)0,                       0 },
844 #endif
845 
846 #define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[38].pCurrent)
847 
848   { "HeapFree",                (SYSCALL)HeapFree,                0 },
849 
850 #define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[39].pCurrent)
851 
852   { "HeapReAlloc",             (SYSCALL)HeapReAlloc,             0 },
853 
854 #define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
855         SIZE_T))aSyscall[40].pCurrent)
856 
857   { "HeapSize",                (SYSCALL)HeapSize,                0 },
858 
859 #define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
860         LPCVOID))aSyscall[41].pCurrent)
861 
862 #if !SQLITE_OS_WINRT
863   { "HeapValidate",            (SYSCALL)HeapValidate,            0 },
864 #else
865   { "HeapValidate",            (SYSCALL)0,                       0 },
866 #endif
867 
868 #define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
869         LPCVOID))aSyscall[42].pCurrent)
870 
871 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
872   { "HeapCompact",             (SYSCALL)HeapCompact,             0 },
873 #else
874   { "HeapCompact",             (SYSCALL)0,                       0 },
875 #endif
876 
877 #define osHeapCompact ((UINT(WINAPI*)(HANDLE,DWORD))aSyscall[43].pCurrent)
878 
879 #if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
880   { "LoadLibraryA",            (SYSCALL)LoadLibraryA,            0 },
881 #else
882   { "LoadLibraryA",            (SYSCALL)0,                       0 },
883 #endif
884 
885 #define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[44].pCurrent)
886 
887 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
888         !defined(SQLITE_OMIT_LOAD_EXTENSION)
889   { "LoadLibraryW",            (SYSCALL)LoadLibraryW,            0 },
890 #else
891   { "LoadLibraryW",            (SYSCALL)0,                       0 },
892 #endif
893 
894 #define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[45].pCurrent)
895 
896 #if !SQLITE_OS_WINRT
897   { "LocalFree",               (SYSCALL)LocalFree,               0 },
898 #else
899   { "LocalFree",               (SYSCALL)0,                       0 },
900 #endif
901 
902 #define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[46].pCurrent)
903 
904 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
905   { "LockFile",                (SYSCALL)LockFile,                0 },
906 #else
907   { "LockFile",                (SYSCALL)0,                       0 },
908 #endif
909 
910 #ifndef osLockFile
911 #define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
912         DWORD))aSyscall[47].pCurrent)
913 #endif
914 
915 #if !SQLITE_OS_WINCE
916   { "LockFileEx",              (SYSCALL)LockFileEx,              0 },
917 #else
918   { "LockFileEx",              (SYSCALL)0,                       0 },
919 #endif
920 
921 #ifndef osLockFileEx
922 #define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
923         LPOVERLAPPED))aSyscall[48].pCurrent)
924 #endif
925 
926 #if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && \
927         (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0))
928   { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
929 #else
930   { "MapViewOfFile",           (SYSCALL)0,                       0 },
931 #endif
932 
933 #define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
934         SIZE_T))aSyscall[49].pCurrent)
935 
936   { "MultiByteToWideChar",     (SYSCALL)MultiByteToWideChar,     0 },
937 
938 #define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
939         int))aSyscall[50].pCurrent)
940 
941   { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },
942 
943 #define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
944         LARGE_INTEGER*))aSyscall[51].pCurrent)
945 
946   { "ReadFile",                (SYSCALL)ReadFile,                0 },
947 
948 #define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
949         LPOVERLAPPED))aSyscall[52].pCurrent)
950 
951   { "SetEndOfFile",            (SYSCALL)SetEndOfFile,            0 },
952 
953 #define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[53].pCurrent)
954 
955 #if !SQLITE_OS_WINRT
956   { "SetFilePointer",          (SYSCALL)SetFilePointer,          0 },
957 #else
958   { "SetFilePointer",          (SYSCALL)0,                       0 },
959 #endif
960 
961 #define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
962         DWORD))aSyscall[54].pCurrent)
963 
964 #if !SQLITE_OS_WINRT
965   { "Sleep",                   (SYSCALL)Sleep,                   0 },
966 #else
967   { "Sleep",                   (SYSCALL)0,                       0 },
968 #endif
969 
970 #define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[55].pCurrent)
971 
972   { "SystemTimeToFileTime",    (SYSCALL)SystemTimeToFileTime,    0 },
973 
974 #define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
975         LPFILETIME))aSyscall[56].pCurrent)
976 
977 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
978   { "UnlockFile",              (SYSCALL)UnlockFile,              0 },
979 #else
980   { "UnlockFile",              (SYSCALL)0,                       0 },
981 #endif
982 
983 #ifndef osUnlockFile
984 #define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
985         DWORD))aSyscall[57].pCurrent)
986 #endif
987 
988 #if !SQLITE_OS_WINCE
989   { "UnlockFileEx",            (SYSCALL)UnlockFileEx,            0 },
990 #else
991   { "UnlockFileEx",            (SYSCALL)0,                       0 },
992 #endif
993 
994 #define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
995         LPOVERLAPPED))aSyscall[58].pCurrent)
996 
997 #if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
998   { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
999 #else
1000   { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
1001 #endif
1002 
1003 #define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[59].pCurrent)
1004 
1005   { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },
1006 
1007 #define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
1008         LPCSTR,LPBOOL))aSyscall[60].pCurrent)
1009 
1010   { "WriteFile",               (SYSCALL)WriteFile,               0 },
1011 
1012 #define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
1013         LPOVERLAPPED))aSyscall[61].pCurrent)
1014 
1015 #if SQLITE_OS_WINRT
1016   { "CreateEventExW",          (SYSCALL)CreateEventExW,          0 },
1017 #else
1018   { "CreateEventExW",          (SYSCALL)0,                       0 },
1019 #endif
1020 
1021 #define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
1022         DWORD,DWORD))aSyscall[62].pCurrent)
1023 
1024 #if !SQLITE_OS_WINRT
1025   { "WaitForSingleObject",     (SYSCALL)WaitForSingleObject,     0 },
1026 #else
1027   { "WaitForSingleObject",     (SYSCALL)0,                       0 },
1028 #endif
1029 
1030 #define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
1031         DWORD))aSyscall[63].pCurrent)
1032 
1033 #if !SQLITE_OS_WINCE
1034   { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
1035 #else
1036   { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
1037 #endif
1038 
1039 #define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
1040         BOOL))aSyscall[64].pCurrent)
1041 
1042 #if SQLITE_OS_WINRT
1043   { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
1044 #else
1045   { "SetFilePointerEx",        (SYSCALL)0,                       0 },
1046 #endif
1047 
1048 #define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
1049         PLARGE_INTEGER,DWORD))aSyscall[65].pCurrent)
1050 
1051 #if SQLITE_OS_WINRT
1052   { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
1053 #else
1054   { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
1055 #endif
1056 
1057 #define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
1058         FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[66].pCurrent)
1059 
1060 #if SQLITE_OS_WINRT && (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
1061   { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
1062 #else
1063   { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
1064 #endif
1065 
1066 #define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
1067         SIZE_T))aSyscall[67].pCurrent)
1068 
1069 #if SQLITE_OS_WINRT
1070   { "CreateFile2",             (SYSCALL)CreateFile2,             0 },
1071 #else
1072   { "CreateFile2",             (SYSCALL)0,                       0 },
1073 #endif
1074 
1075 #define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
1076         LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[68].pCurrent)
1077 
1078 #if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
1079   { "LoadPackagedLibrary",     (SYSCALL)LoadPackagedLibrary,     0 },
1080 #else
1081   { "LoadPackagedLibrary",     (SYSCALL)0,                       0 },
1082 #endif
1083 
1084 #define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
1085         DWORD))aSyscall[69].pCurrent)
1086 
1087 #if SQLITE_OS_WINRT
1088   { "GetTickCount64",          (SYSCALL)GetTickCount64,          0 },
1089 #else
1090   { "GetTickCount64",          (SYSCALL)0,                       0 },
1091 #endif
1092 
1093 #define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[70].pCurrent)
1094 
1095 #if SQLITE_OS_WINRT
1096   { "GetNativeSystemInfo",     (SYSCALL)GetNativeSystemInfo,     0 },
1097 #else
1098   { "GetNativeSystemInfo",     (SYSCALL)0,                       0 },
1099 #endif
1100 
1101 #define osGetNativeSystemInfo ((VOID(WINAPI*)( \
1102         LPSYSTEM_INFO))aSyscall[71].pCurrent)
1103 
1104 #if defined(SQLITE_WIN32_HAS_ANSI)
1105   { "OutputDebugStringA",      (SYSCALL)OutputDebugStringA,      0 },
1106 #else
1107   { "OutputDebugStringA",      (SYSCALL)0,                       0 },
1108 #endif
1109 
1110 #define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[72].pCurrent)
1111 
1112 #if defined(SQLITE_WIN32_HAS_WIDE)
1113   { "OutputDebugStringW",      (SYSCALL)OutputDebugStringW,      0 },
1114 #else
1115   { "OutputDebugStringW",      (SYSCALL)0,                       0 },
1116 #endif
1117 
1118 #define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[73].pCurrent)
1119 
1120   { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },
1121 
1122 #define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[74].pCurrent)
1123 
1124 #if SQLITE_OS_WINRT && (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
1125   { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
1126 #else
1127   { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
1128 #endif
1129 
1130 #define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
1131         LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[75].pCurrent)
1132 
1133 /*
1134 ** NOTE: On some sub-platforms, the InterlockedCompareExchange "function"
1135 **       is really just a macro that uses a compiler intrinsic (e.g. x64).
1136 **       So do not try to make this is into a redefinable interface.
1137 */
1138 #if defined(InterlockedCompareExchange)
1139   { "InterlockedCompareExchange", (SYSCALL)0,                    0 },
1140 
1141 #define osInterlockedCompareExchange InterlockedCompareExchange
1142 #else
1143   { "InterlockedCompareExchange", (SYSCALL)InterlockedCompareExchange, 0 },
1144 
1145 #define osInterlockedCompareExchange ((LONG(WINAPI*)(LONG \
1146         SQLITE_WIN32_VOLATILE*, LONG,LONG))aSyscall[76].pCurrent)
1147 #endif /* defined(InterlockedCompareExchange) */
1148 
1149 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
1150   { "UuidCreate",               (SYSCALL)UuidCreate,             0 },
1151 #else
1152   { "UuidCreate",               (SYSCALL)0,                      0 },
1153 #endif
1154 
1155 #define osUuidCreate ((RPC_STATUS(RPC_ENTRY*)(UUID*))aSyscall[77].pCurrent)
1156 
1157 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
1158   { "UuidCreateSequential",     (SYSCALL)UuidCreateSequential,   0 },
1159 #else
1160   { "UuidCreateSequential",     (SYSCALL)0,                      0 },
1161 #endif
1162 
1163 #define osUuidCreateSequential \
1164         ((RPC_STATUS(RPC_ENTRY*)(UUID*))aSyscall[78].pCurrent)
1165 
1166 #if !defined(SQLITE_NO_SYNC) && SQLITE_MAX_MMAP_SIZE>0
1167   { "FlushViewOfFile",          (SYSCALL)FlushViewOfFile,        0 },
1168 #else
1169   { "FlushViewOfFile",          (SYSCALL)0,                      0 },
1170 #endif
1171 
1172 #define osFlushViewOfFile \
1173         ((BOOL(WINAPI*)(LPCVOID,SIZE_T))aSyscall[79].pCurrent)
1174 
1175 }; /* End of the overrideable system calls */
1176 
1177 /*
1178 ** This is the xSetSystemCall() method of sqlite3_vfs for all of the
1179 ** "win32" VFSes.  Return SQLITE_OK opon successfully updating the
1180 ** system call pointer, or SQLITE_NOTFOUND if there is no configurable
1181 ** system call named zName.
1182 */
1183 static int winSetSystemCall(
1184   sqlite3_vfs *pNotUsed,        /* The VFS pointer.  Not used */
1185   const char *zName,            /* Name of system call to override */
1186   sqlite3_syscall_ptr pNewFunc  /* Pointer to new system call value */
1187 ){
1188   unsigned int i;
1189   int rc = SQLITE_NOTFOUND;
1190 
1191   UNUSED_PARAMETER(pNotUsed);
1192   if( zName==0 ){
1193     /* If no zName is given, restore all system calls to their default
1194     ** settings and return NULL
1195     */
1196     rc = SQLITE_OK;
1197     for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1198       if( aSyscall[i].pDefault ){
1199         aSyscall[i].pCurrent = aSyscall[i].pDefault;
1200       }
1201     }
1202   }else{
1203     /* If zName is specified, operate on only the one system call
1204     ** specified.
1205     */
1206     for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1207       if( strcmp(zName, aSyscall[i].zName)==0 ){
1208         if( aSyscall[i].pDefault==0 ){
1209           aSyscall[i].pDefault = aSyscall[i].pCurrent;
1210         }
1211         rc = SQLITE_OK;
1212         if( pNewFunc==0 ) pNewFunc = aSyscall[i].pDefault;
1213         aSyscall[i].pCurrent = pNewFunc;
1214         break;
1215       }
1216     }
1217   }
1218   return rc;
1219 }
1220 
1221 /*
1222 ** Return the value of a system call.  Return NULL if zName is not a
1223 ** recognized system call name.  NULL is also returned if the system call
1224 ** is currently undefined.
1225 */
1226 static sqlite3_syscall_ptr winGetSystemCall(
1227   sqlite3_vfs *pNotUsed,
1228   const char *zName
1229 ){
1230   unsigned int i;
1231 
1232   UNUSED_PARAMETER(pNotUsed);
1233   for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1234     if( strcmp(zName, aSyscall[i].zName)==0 ) return aSyscall[i].pCurrent;
1235   }
1236   return 0;
1237 }
1238 
1239 /*
1240 ** Return the name of the first system call after zName.  If zName==NULL
1241 ** then return the name of the first system call.  Return NULL if zName
1242 ** is the last system call or if zName is not the name of a valid
1243 ** system call.
1244 */
1245 static const char *winNextSystemCall(sqlite3_vfs *p, const char *zName){
1246   int i = -1;
1247 
1248   UNUSED_PARAMETER(p);
1249   if( zName ){
1250     for(i=0; i<ArraySize(aSyscall)-1; i++){
1251       if( strcmp(zName, aSyscall[i].zName)==0 ) break;
1252     }
1253   }
1254   for(i++; i<ArraySize(aSyscall); i++){
1255     if( aSyscall[i].pCurrent!=0 ) return aSyscall[i].zName;
1256   }
1257   return 0;
1258 }
1259 
1260 #ifdef SQLITE_WIN32_MALLOC
1261 /*
1262 ** If a Win32 native heap has been configured, this function will attempt to
1263 ** compact it.  Upon success, SQLITE_OK will be returned.  Upon failure, one
1264 ** of SQLITE_NOMEM, SQLITE_ERROR, or SQLITE_NOTFOUND will be returned.  The
1265 ** "pnLargest" argument, if non-zero, will be used to return the size of the
1266 ** largest committed free block in the heap, in bytes.
1267 */
1268 int sqlite3_win32_compact_heap(LPUINT pnLargest){
1269   int rc = SQLITE_OK;
1270   UINT nLargest = 0;
1271   HANDLE hHeap;
1272 
1273   winMemAssertMagic();
1274   hHeap = winMemGetHeap();
1275   assert( hHeap!=0 );
1276   assert( hHeap!=INVALID_HANDLE_VALUE );
1277 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1278   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1279 #endif
1280 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
1281   if( (nLargest=osHeapCompact(hHeap, SQLITE_WIN32_HEAP_FLAGS))==0 ){
1282     DWORD lastErrno = osGetLastError();
1283     if( lastErrno==NO_ERROR ){
1284       sqlite3_log(SQLITE_NOMEM, "failed to HeapCompact (no space), heap=%p",
1285                   (void*)hHeap);
1286       rc = SQLITE_NOMEM_BKPT;
1287     }else{
1288       sqlite3_log(SQLITE_ERROR, "failed to HeapCompact (%lu), heap=%p",
1289                   osGetLastError(), (void*)hHeap);
1290       rc = SQLITE_ERROR;
1291     }
1292   }
1293 #else
1294   sqlite3_log(SQLITE_NOTFOUND, "failed to HeapCompact, heap=%p",
1295               (void*)hHeap);
1296   rc = SQLITE_NOTFOUND;
1297 #endif
1298   if( pnLargest ) *pnLargest = nLargest;
1299   return rc;
1300 }
1301 
1302 /*
1303 ** If a Win32 native heap has been configured, this function will attempt to
1304 ** destroy and recreate it.  If the Win32 native heap is not isolated and/or
1305 ** the sqlite3_memory_used() function does not return zero, SQLITE_BUSY will
1306 ** be returned and no changes will be made to the Win32 native heap.
1307 */
1308 int sqlite3_win32_reset_heap(){
1309   int rc;
1310   MUTEX_LOGIC( sqlite3_mutex *pMaster; ) /* The main static mutex */
1311   MUTEX_LOGIC( sqlite3_mutex *pMem; )    /* The memsys static mutex */
1312   MUTEX_LOGIC( pMaster = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER); )
1313   MUTEX_LOGIC( pMem = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM); )
1314   sqlite3_mutex_enter(pMaster);
1315   sqlite3_mutex_enter(pMem);
1316   winMemAssertMagic();
1317   if( winMemGetHeap()!=NULL && winMemGetOwned() && sqlite3_memory_used()==0 ){
1318     /*
1319     ** At this point, there should be no outstanding memory allocations on
1320     ** the heap.  Also, since both the master and memsys locks are currently
1321     ** being held by us, no other function (i.e. from another thread) should
1322     ** be able to even access the heap.  Attempt to destroy and recreate our
1323     ** isolated Win32 native heap now.
1324     */
1325     assert( winMemGetHeap()!=NULL );
1326     assert( winMemGetOwned() );
1327     assert( sqlite3_memory_used()==0 );
1328     winMemShutdown(winMemGetDataPtr());
1329     assert( winMemGetHeap()==NULL );
1330     assert( !winMemGetOwned() );
1331     assert( sqlite3_memory_used()==0 );
1332     rc = winMemInit(winMemGetDataPtr());
1333     assert( rc!=SQLITE_OK || winMemGetHeap()!=NULL );
1334     assert( rc!=SQLITE_OK || winMemGetOwned() );
1335     assert( rc!=SQLITE_OK || sqlite3_memory_used()==0 );
1336   }else{
1337     /*
1338     ** The Win32 native heap cannot be modified because it may be in use.
1339     */
1340     rc = SQLITE_BUSY;
1341   }
1342   sqlite3_mutex_leave(pMem);
1343   sqlite3_mutex_leave(pMaster);
1344   return rc;
1345 }
1346 #endif /* SQLITE_WIN32_MALLOC */
1347 
1348 /*
1349 ** This function outputs the specified (ANSI) string to the Win32 debugger
1350 ** (if available).
1351 */
1352 
1353 void sqlite3_win32_write_debug(const char *zBuf, int nBuf){
1354   char zDbgBuf[SQLITE_WIN32_DBG_BUF_SIZE];
1355   int nMin = MIN(nBuf, (SQLITE_WIN32_DBG_BUF_SIZE - 1)); /* may be negative. */
1356   if( nMin<-1 ) nMin = -1; /* all negative values become -1. */
1357   assert( nMin==-1 || nMin==0 || nMin<SQLITE_WIN32_DBG_BUF_SIZE );
1358 #ifdef SQLITE_ENABLE_API_ARMOR
1359   if( !zBuf ){
1360     (void)SQLITE_MISUSE_BKPT;
1361     return;
1362   }
1363 #endif
1364 #if defined(SQLITE_WIN32_HAS_ANSI)
1365   if( nMin>0 ){
1366     memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1367     memcpy(zDbgBuf, zBuf, nMin);
1368     osOutputDebugStringA(zDbgBuf);
1369   }else{
1370     osOutputDebugStringA(zBuf);
1371   }
1372 #elif defined(SQLITE_WIN32_HAS_WIDE)
1373   memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1374   if ( osMultiByteToWideChar(
1375           osAreFileApisANSI() ? CP_ACP : CP_OEMCP, 0, zBuf,
1376           nMin, (LPWSTR)zDbgBuf, SQLITE_WIN32_DBG_BUF_SIZE/sizeof(WCHAR))<=0 ){
1377     return;
1378   }
1379   osOutputDebugStringW((LPCWSTR)zDbgBuf);
1380 #else
1381   if( nMin>0 ){
1382     memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1383     memcpy(zDbgBuf, zBuf, nMin);
1384     fprintf(stderr, "%s", zDbgBuf);
1385   }else{
1386     fprintf(stderr, "%s", zBuf);
1387   }
1388 #endif
1389 }
1390 
1391 /*
1392 ** The following routine suspends the current thread for at least ms
1393 ** milliseconds.  This is equivalent to the Win32 Sleep() interface.
1394 */
1395 #if SQLITE_OS_WINRT
1396 static HANDLE sleepObj = NULL;
1397 #endif
1398 
1399 void sqlite3_win32_sleep(DWORD milliseconds){
1400 #if SQLITE_OS_WINRT
1401   if ( sleepObj==NULL ){
1402     sleepObj = osCreateEventExW(NULL, NULL, CREATE_EVENT_MANUAL_RESET,
1403                                 SYNCHRONIZE);
1404   }
1405   assert( sleepObj!=NULL );
1406   osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
1407 #else
1408   osSleep(milliseconds);
1409 #endif
1410 }
1411 
1412 #if SQLITE_MAX_WORKER_THREADS>0 && !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
1413         SQLITE_THREADSAFE>0
1414 DWORD sqlite3Win32Wait(HANDLE hObject){
1415   DWORD rc;
1416   while( (rc = osWaitForSingleObjectEx(hObject, INFINITE,
1417                                        TRUE))==WAIT_IO_COMPLETION ){}
1418   return rc;
1419 }
1420 #endif
1421 
1422 /*
1423 ** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
1424 ** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
1425 **
1426 ** Here is an interesting observation:  Win95, Win98, and WinME lack
1427 ** the LockFileEx() API.  But we can still statically link against that
1428 ** API as long as we don't call it when running Win95/98/ME.  A call to
1429 ** this routine is used to determine if the host is Win95/98/ME or
1430 ** WinNT/2K/XP so that we will know whether or not we can safely call
1431 ** the LockFileEx() API.
1432 */
1433 
1434 #if !SQLITE_WIN32_GETVERSIONEX
1435 # define osIsNT()  (1)
1436 #elif SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
1437 # define osIsNT()  (1)
1438 #elif !defined(SQLITE_WIN32_HAS_WIDE)
1439 # define osIsNT()  (0)
1440 #else
1441 # define osIsNT()  ((sqlite3_os_type==2) || sqlite3_win32_is_nt())
1442 #endif
1443 
1444 /*
1445 ** This function determines if the machine is running a version of Windows
1446 ** based on the NT kernel.
1447 */
1448 int sqlite3_win32_is_nt(void){
1449 #if SQLITE_OS_WINRT
1450   /*
1451   ** NOTE: The WinRT sub-platform is always assumed to be based on the NT
1452   **       kernel.
1453   */
1454   return 1;
1455 #elif SQLITE_WIN32_GETVERSIONEX
1456   if( osInterlockedCompareExchange(&sqlite3_os_type, 0, 0)==0 ){
1457 #if defined(SQLITE_WIN32_HAS_ANSI)
1458     OSVERSIONINFOA sInfo;
1459     sInfo.dwOSVersionInfoSize = sizeof(sInfo);
1460     osGetVersionExA(&sInfo);
1461     osInterlockedCompareExchange(&sqlite3_os_type,
1462         (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1, 0);
1463 #elif defined(SQLITE_WIN32_HAS_WIDE)
1464     OSVERSIONINFOW sInfo;
1465     sInfo.dwOSVersionInfoSize = sizeof(sInfo);
1466     osGetVersionExW(&sInfo);
1467     osInterlockedCompareExchange(&sqlite3_os_type,
1468         (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1, 0);
1469 #endif
1470   }
1471   return osInterlockedCompareExchange(&sqlite3_os_type, 2, 2)==2;
1472 #elif SQLITE_TEST
1473   return osInterlockedCompareExchange(&sqlite3_os_type, 2, 2)==2;
1474 #else
1475   /*
1476   ** NOTE: All sub-platforms where the GetVersionEx[AW] functions are
1477   **       deprecated are always assumed to be based on the NT kernel.
1478   */
1479   return 1;
1480 #endif
1481 }
1482 
1483 #ifdef SQLITE_WIN32_MALLOC
1484 /*
1485 ** Allocate nBytes of memory.
1486 */
1487 static void *winMemMalloc(int nBytes){
1488   HANDLE hHeap;
1489   void *p;
1490 
1491   winMemAssertMagic();
1492   hHeap = winMemGetHeap();
1493   assert( hHeap!=0 );
1494   assert( hHeap!=INVALID_HANDLE_VALUE );
1495 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1496   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1497 #endif
1498   assert( nBytes>=0 );
1499   p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
1500   if( !p ){
1501     sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%lu), heap=%p",
1502                 nBytes, osGetLastError(), (void*)hHeap);
1503   }
1504   return p;
1505 }
1506 
1507 /*
1508 ** Free memory.
1509 */
1510 static void winMemFree(void *pPrior){
1511   HANDLE hHeap;
1512 
1513   winMemAssertMagic();
1514   hHeap = winMemGetHeap();
1515   assert( hHeap!=0 );
1516   assert( hHeap!=INVALID_HANDLE_VALUE );
1517 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1518   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
1519 #endif
1520   if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
1521   if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
1522     sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%lu), heap=%p",
1523                 pPrior, osGetLastError(), (void*)hHeap);
1524   }
1525 }
1526 
1527 /*
1528 ** Change the size of an existing memory allocation
1529 */
1530 static void *winMemRealloc(void *pPrior, int nBytes){
1531   HANDLE hHeap;
1532   void *p;
1533 
1534   winMemAssertMagic();
1535   hHeap = winMemGetHeap();
1536   assert( hHeap!=0 );
1537   assert( hHeap!=INVALID_HANDLE_VALUE );
1538 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1539   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
1540 #endif
1541   assert( nBytes>=0 );
1542   if( !pPrior ){
1543     p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
1544   }else{
1545     p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
1546   }
1547   if( !p ){
1548     sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%lu), heap=%p",
1549                 pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
1550                 (void*)hHeap);
1551   }
1552   return p;
1553 }
1554 
1555 /*
1556 ** Return the size of an outstanding allocation, in bytes.
1557 */
1558 static int winMemSize(void *p){
1559   HANDLE hHeap;
1560   SIZE_T n;
1561 
1562   winMemAssertMagic();
1563   hHeap = winMemGetHeap();
1564   assert( hHeap!=0 );
1565   assert( hHeap!=INVALID_HANDLE_VALUE );
1566 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1567   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, p) );
1568 #endif
1569   if( !p ) return 0;
1570   n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
1571   if( n==(SIZE_T)-1 ){
1572     sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%lu), heap=%p",
1573                 p, osGetLastError(), (void*)hHeap);
1574     return 0;
1575   }
1576   return (int)n;
1577 }
1578 
1579 /*
1580 ** Round up a request size to the next valid allocation size.
1581 */
1582 static int winMemRoundup(int n){
1583   return n;
1584 }
1585 
1586 /*
1587 ** Initialize this module.
1588 */
1589 static int winMemInit(void *pAppData){
1590   winMemData *pWinMemData = (winMemData *)pAppData;
1591 
1592   if( !pWinMemData ) return SQLITE_ERROR;
1593   assert( pWinMemData->magic1==WINMEM_MAGIC1 );
1594   assert( pWinMemData->magic2==WINMEM_MAGIC2 );
1595 
1596 #if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
1597   if( !pWinMemData->hHeap ){
1598     DWORD dwInitialSize = SQLITE_WIN32_HEAP_INIT_SIZE;
1599     DWORD dwMaximumSize = (DWORD)sqlite3GlobalConfig.nHeap;
1600     if( dwMaximumSize==0 ){
1601       dwMaximumSize = SQLITE_WIN32_HEAP_MAX_SIZE;
1602     }else if( dwInitialSize>dwMaximumSize ){
1603       dwInitialSize = dwMaximumSize;
1604     }
1605     pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
1606                                       dwInitialSize, dwMaximumSize);
1607     if( !pWinMemData->hHeap ){
1608       sqlite3_log(SQLITE_NOMEM,
1609           "failed to HeapCreate (%lu), flags=%u, initSize=%lu, maxSize=%lu",
1610           osGetLastError(), SQLITE_WIN32_HEAP_FLAGS, dwInitialSize,
1611           dwMaximumSize);
1612       return SQLITE_NOMEM_BKPT;
1613     }
1614     pWinMemData->bOwned = TRUE;
1615     assert( pWinMemData->bOwned );
1616   }
1617 #else
1618   pWinMemData->hHeap = osGetProcessHeap();
1619   if( !pWinMemData->hHeap ){
1620     sqlite3_log(SQLITE_NOMEM,
1621         "failed to GetProcessHeap (%lu)", osGetLastError());
1622     return SQLITE_NOMEM_BKPT;
1623   }
1624   pWinMemData->bOwned = FALSE;
1625   assert( !pWinMemData->bOwned );
1626 #endif
1627   assert( pWinMemData->hHeap!=0 );
1628   assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
1629 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1630   assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1631 #endif
1632   return SQLITE_OK;
1633 }
1634 
1635 /*
1636 ** Deinitialize this module.
1637 */
1638 static void winMemShutdown(void *pAppData){
1639   winMemData *pWinMemData = (winMemData *)pAppData;
1640 
1641   if( !pWinMemData ) return;
1642   assert( pWinMemData->magic1==WINMEM_MAGIC1 );
1643   assert( pWinMemData->magic2==WINMEM_MAGIC2 );
1644 
1645   if( pWinMemData->hHeap ){
1646     assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
1647 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1648     assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1649 #endif
1650     if( pWinMemData->bOwned ){
1651       if( !osHeapDestroy(pWinMemData->hHeap) ){
1652         sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%lu), heap=%p",
1653                     osGetLastError(), (void*)pWinMemData->hHeap);
1654       }
1655       pWinMemData->bOwned = FALSE;
1656     }
1657     pWinMemData->hHeap = NULL;
1658   }
1659 }
1660 
1661 /*
1662 ** Populate the low-level memory allocation function pointers in
1663 ** sqlite3GlobalConfig.m with pointers to the routines in this file. The
1664 ** arguments specify the block of memory to manage.
1665 **
1666 ** This routine is only called by sqlite3_config(), and therefore
1667 ** is not required to be threadsafe (it is not).
1668 */
1669 const sqlite3_mem_methods *sqlite3MemGetWin32(void){
1670   static const sqlite3_mem_methods winMemMethods = {
1671     winMemMalloc,
1672     winMemFree,
1673     winMemRealloc,
1674     winMemSize,
1675     winMemRoundup,
1676     winMemInit,
1677     winMemShutdown,
1678     &win_mem_data
1679   };
1680   return &winMemMethods;
1681 }
1682 
1683 void sqlite3MemSetDefault(void){
1684   sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetWin32());
1685 }
1686 #endif /* SQLITE_WIN32_MALLOC */
1687 
1688 /*
1689 ** Convert a UTF-8 string to Microsoft Unicode.
1690 **
1691 ** Space to hold the returned string is obtained from sqlite3_malloc().
1692 */
1693 static LPWSTR winUtf8ToUnicode(const char *zText){
1694   int nChar;
1695   LPWSTR zWideText;
1696 
1697   nChar = osMultiByteToWideChar(CP_UTF8, 0, zText, -1, NULL, 0);
1698   if( nChar==0 ){
1699     return 0;
1700   }
1701   zWideText = sqlite3MallocZero( nChar*sizeof(WCHAR) );
1702   if( zWideText==0 ){
1703     return 0;
1704   }
1705   nChar = osMultiByteToWideChar(CP_UTF8, 0, zText, -1, zWideText,
1706                                 nChar);
1707   if( nChar==0 ){
1708     sqlite3_free(zWideText);
1709     zWideText = 0;
1710   }
1711   return zWideText;
1712 }
1713 
1714 /*
1715 ** Convert a Microsoft Unicode string to UTF-8.
1716 **
1717 ** Space to hold the returned string is obtained from sqlite3_malloc().
1718 */
1719 static char *winUnicodeToUtf8(LPCWSTR zWideText){
1720   int nByte;
1721   char *zText;
1722 
1723   nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideText, -1, 0, 0, 0, 0);
1724   if( nByte == 0 ){
1725     return 0;
1726   }
1727   zText = sqlite3MallocZero( nByte );
1728   if( zText==0 ){
1729     return 0;
1730   }
1731   nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideText, -1, zText, nByte,
1732                                 0, 0);
1733   if( nByte == 0 ){
1734     sqlite3_free(zText);
1735     zText = 0;
1736   }
1737   return zText;
1738 }
1739 
1740 /*
1741 ** Convert an ANSI string to Microsoft Unicode, using the ANSI or OEM
1742 ** code page.
1743 **
1744 ** Space to hold the returned string is obtained from sqlite3_malloc().
1745 */
1746 static LPWSTR winMbcsToUnicode(const char *zText, int useAnsi){
1747   int nByte;
1748   LPWSTR zMbcsText;
1749   int codepage = useAnsi ? CP_ACP : CP_OEMCP;
1750 
1751   nByte = osMultiByteToWideChar(codepage, 0, zText, -1, NULL,
1752                                 0)*sizeof(WCHAR);
1753   if( nByte==0 ){
1754     return 0;
1755   }
1756   zMbcsText = sqlite3MallocZero( nByte*sizeof(WCHAR) );
1757   if( zMbcsText==0 ){
1758     return 0;
1759   }
1760   nByte = osMultiByteToWideChar(codepage, 0, zText, -1, zMbcsText,
1761                                 nByte);
1762   if( nByte==0 ){
1763     sqlite3_free(zMbcsText);
1764     zMbcsText = 0;
1765   }
1766   return zMbcsText;
1767 }
1768 
1769 /*
1770 ** Convert a Microsoft Unicode string to a multi-byte character string,
1771 ** using the ANSI or OEM code page.
1772 **
1773 ** Space to hold the returned string is obtained from sqlite3_malloc().
1774 */
1775 static char *winUnicodeToMbcs(LPCWSTR zWideText, int useAnsi){
1776   int nByte;
1777   char *zText;
1778   int codepage = useAnsi ? CP_ACP : CP_OEMCP;
1779 
1780   nByte = osWideCharToMultiByte(codepage, 0, zWideText, -1, 0, 0, 0, 0);
1781   if( nByte == 0 ){
1782     return 0;
1783   }
1784   zText = sqlite3MallocZero( nByte );
1785   if( zText==0 ){
1786     return 0;
1787   }
1788   nByte = osWideCharToMultiByte(codepage, 0, zWideText, -1, zText,
1789                                 nByte, 0, 0);
1790   if( nByte == 0 ){
1791     sqlite3_free(zText);
1792     zText = 0;
1793   }
1794   return zText;
1795 }
1796 
1797 /*
1798 ** Convert a multi-byte character string to UTF-8.
1799 **
1800 ** Space to hold the returned string is obtained from sqlite3_malloc().
1801 */
1802 static char *winMbcsToUtf8(const char *zText, int useAnsi){
1803   char *zTextUtf8;
1804   LPWSTR zTmpWide;
1805 
1806   zTmpWide = winMbcsToUnicode(zText, useAnsi);
1807   if( zTmpWide==0 ){
1808     return 0;
1809   }
1810   zTextUtf8 = winUnicodeToUtf8(zTmpWide);
1811   sqlite3_free(zTmpWide);
1812   return zTextUtf8;
1813 }
1814 
1815 /*
1816 ** Convert a UTF-8 string to a multi-byte character string.
1817 **
1818 ** Space to hold the returned string is obtained from sqlite3_malloc().
1819 */
1820 static char *winUtf8ToMbcs(const char *zText, int useAnsi){
1821   char *zTextMbcs;
1822   LPWSTR zTmpWide;
1823 
1824   zTmpWide = winUtf8ToUnicode(zText);
1825   if( zTmpWide==0 ){
1826     return 0;
1827   }
1828   zTextMbcs = winUnicodeToMbcs(zTmpWide, useAnsi);
1829   sqlite3_free(zTmpWide);
1830   return zTextMbcs;
1831 }
1832 
1833 /*
1834 ** This is a public wrapper for the winUtf8ToUnicode() function.
1835 */
1836 LPWSTR sqlite3_win32_utf8_to_unicode(const char *zText){
1837 #ifdef SQLITE_ENABLE_API_ARMOR
1838   if( !zText ){
1839     (void)SQLITE_MISUSE_BKPT;
1840     return 0;
1841   }
1842 #endif
1843 #ifndef SQLITE_OMIT_AUTOINIT
1844   if( sqlite3_initialize() ) return 0;
1845 #endif
1846   return winUtf8ToUnicode(zText);
1847 }
1848 
1849 /*
1850 ** This is a public wrapper for the winUnicodeToUtf8() function.
1851 */
1852 char *sqlite3_win32_unicode_to_utf8(LPCWSTR zWideText){
1853 #ifdef SQLITE_ENABLE_API_ARMOR
1854   if( !zWideText ){
1855     (void)SQLITE_MISUSE_BKPT;
1856     return 0;
1857   }
1858 #endif
1859 #ifndef SQLITE_OMIT_AUTOINIT
1860   if( sqlite3_initialize() ) return 0;
1861 #endif
1862   return winUnicodeToUtf8(zWideText);
1863 }
1864 
1865 /*
1866 ** This is a public wrapper for the winMbcsToUtf8() function.
1867 */
1868 char *sqlite3_win32_mbcs_to_utf8(const char *zText){
1869 #ifdef SQLITE_ENABLE_API_ARMOR
1870   if( !zText ){
1871     (void)SQLITE_MISUSE_BKPT;
1872     return 0;
1873   }
1874 #endif
1875 #ifndef SQLITE_OMIT_AUTOINIT
1876   if( sqlite3_initialize() ) return 0;
1877 #endif
1878   return winMbcsToUtf8(zText, osAreFileApisANSI());
1879 }
1880 
1881 /*
1882 ** This is a public wrapper for the winMbcsToUtf8() function.
1883 */
1884 char *sqlite3_win32_mbcs_to_utf8_v2(const char *zText, int useAnsi){
1885 #ifdef SQLITE_ENABLE_API_ARMOR
1886   if( !zText ){
1887     (void)SQLITE_MISUSE_BKPT;
1888     return 0;
1889   }
1890 #endif
1891 #ifndef SQLITE_OMIT_AUTOINIT
1892   if( sqlite3_initialize() ) return 0;
1893 #endif
1894   return winMbcsToUtf8(zText, useAnsi);
1895 }
1896 
1897 /*
1898 ** This is a public wrapper for the winUtf8ToMbcs() function.
1899 */
1900 char *sqlite3_win32_utf8_to_mbcs(const char *zText){
1901 #ifdef SQLITE_ENABLE_API_ARMOR
1902   if( !zText ){
1903     (void)SQLITE_MISUSE_BKPT;
1904     return 0;
1905   }
1906 #endif
1907 #ifndef SQLITE_OMIT_AUTOINIT
1908   if( sqlite3_initialize() ) return 0;
1909 #endif
1910   return winUtf8ToMbcs(zText, osAreFileApisANSI());
1911 }
1912 
1913 /*
1914 ** This is a public wrapper for the winUtf8ToMbcs() function.
1915 */
1916 char *sqlite3_win32_utf8_to_mbcs_v2(const char *zText, int useAnsi){
1917 #ifdef SQLITE_ENABLE_API_ARMOR
1918   if( !zText ){
1919     (void)SQLITE_MISUSE_BKPT;
1920     return 0;
1921   }
1922 #endif
1923 #ifndef SQLITE_OMIT_AUTOINIT
1924   if( sqlite3_initialize() ) return 0;
1925 #endif
1926   return winUtf8ToMbcs(zText, useAnsi);
1927 }
1928 
1929 /*
1930 ** This function sets the data directory or the temporary directory based on
1931 ** the provided arguments.  The type argument must be 1 in order to set the
1932 ** data directory or 2 in order to set the temporary directory.  The zValue
1933 ** argument is the name of the directory to use.  The return value will be
1934 ** SQLITE_OK if successful.
1935 */
1936 int sqlite3_win32_set_directory(DWORD type, LPCWSTR zValue){
1937   char **ppDirectory = 0;
1938 #ifndef SQLITE_OMIT_AUTOINIT
1939   int rc = sqlite3_initialize();
1940   if( rc ) return rc;
1941 #endif
1942   if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
1943     ppDirectory = &sqlite3_data_directory;
1944   }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
1945     ppDirectory = &sqlite3_temp_directory;
1946   }
1947   assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
1948           || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
1949   );
1950   assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
1951   if( ppDirectory ){
1952     char *zValueUtf8 = 0;
1953     if( zValue && zValue[0] ){
1954       zValueUtf8 = winUnicodeToUtf8(zValue);
1955       if ( zValueUtf8==0 ){
1956         return SQLITE_NOMEM_BKPT;
1957       }
1958     }
1959     sqlite3_free(*ppDirectory);
1960     *ppDirectory = zValueUtf8;
1961     return SQLITE_OK;
1962   }
1963   return SQLITE_ERROR;
1964 }
1965 
1966 /*
1967 ** The return value of winGetLastErrorMsg
1968 ** is zero if the error message fits in the buffer, or non-zero
1969 ** otherwise (if the message was truncated).
1970 */
1971 static int winGetLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
1972   /* FormatMessage returns 0 on failure.  Otherwise it
1973   ** returns the number of TCHARs written to the output
1974   ** buffer, excluding the terminating null char.
1975   */
1976   DWORD dwLen = 0;
1977   char *zOut = 0;
1978 
1979   if( osIsNT() ){
1980 #if SQLITE_OS_WINRT
1981     WCHAR zTempWide[SQLITE_WIN32_MAX_ERRMSG_CHARS+1];
1982     dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
1983                              FORMAT_MESSAGE_IGNORE_INSERTS,
1984                              NULL,
1985                              lastErrno,
1986                              0,
1987                              zTempWide,
1988                              SQLITE_WIN32_MAX_ERRMSG_CHARS,
1989                              0);
1990 #else
1991     LPWSTR zTempWide = NULL;
1992     dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
1993                              FORMAT_MESSAGE_FROM_SYSTEM |
1994                              FORMAT_MESSAGE_IGNORE_INSERTS,
1995                              NULL,
1996                              lastErrno,
1997                              0,
1998                              (LPWSTR) &zTempWide,
1999                              0,
2000                              0);
2001 #endif
2002     if( dwLen > 0 ){
2003       /* allocate a buffer and convert to UTF8 */
2004       sqlite3BeginBenignMalloc();
2005       zOut = winUnicodeToUtf8(zTempWide);
2006       sqlite3EndBenignMalloc();
2007 #if !SQLITE_OS_WINRT
2008       /* free the system buffer allocated by FormatMessage */
2009       osLocalFree(zTempWide);
2010 #endif
2011     }
2012   }
2013 #ifdef SQLITE_WIN32_HAS_ANSI
2014   else{
2015     char *zTemp = NULL;
2016     dwLen = osFormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
2017                              FORMAT_MESSAGE_FROM_SYSTEM |
2018                              FORMAT_MESSAGE_IGNORE_INSERTS,
2019                              NULL,
2020                              lastErrno,
2021                              0,
2022                              (LPSTR) &zTemp,
2023                              0,
2024                              0);
2025     if( dwLen > 0 ){
2026       /* allocate a buffer and convert to UTF8 */
2027       sqlite3BeginBenignMalloc();
2028       zOut = winMbcsToUtf8(zTemp, osAreFileApisANSI());
2029       sqlite3EndBenignMalloc();
2030       /* free the system buffer allocated by FormatMessage */
2031       osLocalFree(zTemp);
2032     }
2033   }
2034 #endif
2035   if( 0 == dwLen ){
2036     sqlite3_snprintf(nBuf, zBuf, "OsError 0x%lx (%lu)", lastErrno, lastErrno);
2037   }else{
2038     /* copy a maximum of nBuf chars to output buffer */
2039     sqlite3_snprintf(nBuf, zBuf, "%s", zOut);
2040     /* free the UTF8 buffer */
2041     sqlite3_free(zOut);
2042   }
2043   return 0;
2044 }
2045 
2046 /*
2047 **
2048 ** This function - winLogErrorAtLine() - is only ever called via the macro
2049 ** winLogError().
2050 **
2051 ** This routine is invoked after an error occurs in an OS function.
2052 ** It logs a message using sqlite3_log() containing the current value of
2053 ** error code and, if possible, the human-readable equivalent from
2054 ** FormatMessage.
2055 **
2056 ** The first argument passed to the macro should be the error code that
2057 ** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN).
2058 ** The two subsequent arguments should be the name of the OS function that
2059 ** failed and the associated file-system path, if any.
2060 */
2061 #define winLogError(a,b,c,d)   winLogErrorAtLine(a,b,c,d,__LINE__)
2062 static int winLogErrorAtLine(
2063   int errcode,                    /* SQLite error code */
2064   DWORD lastErrno,                /* Win32 last error */
2065   const char *zFunc,              /* Name of OS function that failed */
2066   const char *zPath,              /* File path associated with error */
2067   int iLine                       /* Source line number where error occurred */
2068 ){
2069   char zMsg[500];                 /* Human readable error text */
2070   int i;                          /* Loop counter */
2071 
2072   zMsg[0] = 0;
2073   winGetLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
2074   assert( errcode!=SQLITE_OK );
2075   if( zPath==0 ) zPath = "";
2076   for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
2077   zMsg[i] = 0;
2078   sqlite3_log(errcode,
2079       "os_win.c:%d: (%lu) %s(%s) - %s",
2080       iLine, lastErrno, zFunc, zPath, zMsg
2081   );
2082 
2083   return errcode;
2084 }
2085 
2086 /*
2087 ** The number of times that a ReadFile(), WriteFile(), and DeleteFile()
2088 ** will be retried following a locking error - probably caused by
2089 ** antivirus software.  Also the initial delay before the first retry.
2090 ** The delay increases linearly with each retry.
2091 */
2092 #ifndef SQLITE_WIN32_IOERR_RETRY
2093 # define SQLITE_WIN32_IOERR_RETRY 10
2094 #endif
2095 #ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
2096 # define SQLITE_WIN32_IOERR_RETRY_DELAY 25
2097 #endif
2098 static int winIoerrRetry = SQLITE_WIN32_IOERR_RETRY;
2099 static int winIoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;
2100 
2101 /*
2102 ** The "winIoerrCanRetry1" macro is used to determine if a particular I/O
2103 ** error code obtained via GetLastError() is eligible to be retried.  It
2104 ** must accept the error code DWORD as its only argument and should return
2105 ** non-zero if the error code is transient in nature and the operation
2106 ** responsible for generating the original error might succeed upon being
2107 ** retried.  The argument to this macro should be a variable.
2108 **
2109 ** Additionally, a macro named "winIoerrCanRetry2" may be defined.  If it
2110 ** is defined, it will be consulted only when the macro "winIoerrCanRetry1"
2111 ** returns zero.  The "winIoerrCanRetry2" macro is completely optional and
2112 ** may be used to include additional error codes in the set that should
2113 ** result in the failing I/O operation being retried by the caller.  If
2114 ** defined, the "winIoerrCanRetry2" macro must exhibit external semantics
2115 ** identical to those of the "winIoerrCanRetry1" macro.
2116 */
2117 #if !defined(winIoerrCanRetry1)
2118 #define winIoerrCanRetry1(a) (((a)==ERROR_ACCESS_DENIED)        || \
2119                               ((a)==ERROR_SHARING_VIOLATION)    || \
2120                               ((a)==ERROR_LOCK_VIOLATION)       || \
2121                               ((a)==ERROR_DEV_NOT_EXIST)        || \
2122                               ((a)==ERROR_NETNAME_DELETED)      || \
2123                               ((a)==ERROR_SEM_TIMEOUT)          || \
2124                               ((a)==ERROR_NETWORK_UNREACHABLE))
2125 #endif
2126 
2127 /*
2128 ** If a ReadFile() or WriteFile() error occurs, invoke this routine
2129 ** to see if it should be retried.  Return TRUE to retry.  Return FALSE
2130 ** to give up with an error.
2131 */
2132 static int winRetryIoerr(int *pnRetry, DWORD *pError){
2133   DWORD e = osGetLastError();
2134   if( *pnRetry>=winIoerrRetry ){
2135     if( pError ){
2136       *pError = e;
2137     }
2138     return 0;
2139   }
2140   if( winIoerrCanRetry1(e) ){
2141     sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
2142     ++*pnRetry;
2143     return 1;
2144   }
2145 #if defined(winIoerrCanRetry2)
2146   else if( winIoerrCanRetry2(e) ){
2147     sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
2148     ++*pnRetry;
2149     return 1;
2150   }
2151 #endif
2152   if( pError ){
2153     *pError = e;
2154   }
2155   return 0;
2156 }
2157 
2158 /*
2159 ** Log a I/O error retry episode.
2160 */
2161 static void winLogIoerr(int nRetry, int lineno){
2162   if( nRetry ){
2163     sqlite3_log(SQLITE_NOTICE,
2164       "delayed %dms for lock/sharing conflict at line %d",
2165       winIoerrRetryDelay*nRetry*(nRetry+1)/2, lineno
2166     );
2167   }
2168 }
2169 
2170 /*
2171 ** This #if does not rely on the SQLITE_OS_WINCE define because the
2172 ** corresponding section in "date.c" cannot use it.
2173 */
2174 #if !defined(SQLITE_OMIT_LOCALTIME) && defined(_WIN32_WCE) && \
2175     (!defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API)
2176 /*
2177 ** The MSVC CRT on Windows CE may not have a localtime() function.
2178 ** So define a substitute.
2179 */
2180 #  include <time.h>
2181 struct tm *__cdecl localtime(const time_t *t)
2182 {
2183   static struct tm y;
2184   FILETIME uTm, lTm;
2185   SYSTEMTIME pTm;
2186   sqlite3_int64 t64;
2187   t64 = *t;
2188   t64 = (t64 + 11644473600)*10000000;
2189   uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
2190   uTm.dwHighDateTime= (DWORD)(t64 >> 32);
2191   osFileTimeToLocalFileTime(&uTm,&lTm);
2192   osFileTimeToSystemTime(&lTm,&pTm);
2193   y.tm_year = pTm.wYear - 1900;
2194   y.tm_mon = pTm.wMonth - 1;
2195   y.tm_wday = pTm.wDayOfWeek;
2196   y.tm_mday = pTm.wDay;
2197   y.tm_hour = pTm.wHour;
2198   y.tm_min = pTm.wMinute;
2199   y.tm_sec = pTm.wSecond;
2200   return &y;
2201 }
2202 #endif
2203 
2204 #if SQLITE_OS_WINCE
2205 /*************************************************************************
2206 ** This section contains code for WinCE only.
2207 */
2208 #define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
2209 
2210 /*
2211 ** Acquire a lock on the handle h
2212 */
2213 static void winceMutexAcquire(HANDLE h){
2214    DWORD dwErr;
2215    do {
2216      dwErr = osWaitForSingleObject(h, INFINITE);
2217    } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
2218 }
2219 /*
2220 ** Release a lock acquired by winceMutexAcquire()
2221 */
2222 #define winceMutexRelease(h) ReleaseMutex(h)
2223 
2224 /*
2225 ** Create the mutex and shared memory used for locking in the file
2226 ** descriptor pFile
2227 */
2228 static int winceCreateLock(const char *zFilename, winFile *pFile){
2229   LPWSTR zTok;
2230   LPWSTR zName;
2231   DWORD lastErrno;
2232   BOOL bLogged = FALSE;
2233   BOOL bInit = TRUE;
2234 
2235   zName = winUtf8ToUnicode(zFilename);
2236   if( zName==0 ){
2237     /* out of memory */
2238     return SQLITE_IOERR_NOMEM_BKPT;
2239   }
2240 
2241   /* Initialize the local lockdata */
2242   memset(&pFile->local, 0, sizeof(pFile->local));
2243 
2244   /* Replace the backslashes from the filename and lowercase it
2245   ** to derive a mutex name. */
2246   zTok = osCharLowerW(zName);
2247   for (;*zTok;zTok++){
2248     if (*zTok == '\\') *zTok = '_';
2249   }
2250 
2251   /* Create/open the named mutex */
2252   pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
2253   if (!pFile->hMutex){
2254     pFile->lastErrno = osGetLastError();
2255     sqlite3_free(zName);
2256     return winLogError(SQLITE_IOERR, pFile->lastErrno,
2257                        "winceCreateLock1", zFilename);
2258   }
2259 
2260   /* Acquire the mutex before continuing */
2261   winceMutexAcquire(pFile->hMutex);
2262 
2263   /* Since the names of named mutexes, semaphores, file mappings etc are
2264   ** case-sensitive, take advantage of that by uppercasing the mutex name
2265   ** and using that as the shared filemapping name.
2266   */
2267   osCharUpperW(zName);
2268   pFile->hShared = osCreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
2269                                         PAGE_READWRITE, 0, sizeof(winceLock),
2270                                         zName);
2271 
2272   /* Set a flag that indicates we're the first to create the memory so it
2273   ** must be zero-initialized */
2274   lastErrno = osGetLastError();
2275   if (lastErrno == ERROR_ALREADY_EXISTS){
2276     bInit = FALSE;
2277   }
2278 
2279   sqlite3_free(zName);
2280 
2281   /* If we succeeded in making the shared memory handle, map it. */
2282   if( pFile->hShared ){
2283     pFile->shared = (winceLock*)osMapViewOfFile(pFile->hShared,
2284              FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
2285     /* If mapping failed, close the shared memory handle and erase it */
2286     if( !pFile->shared ){
2287       pFile->lastErrno = osGetLastError();
2288       winLogError(SQLITE_IOERR, pFile->lastErrno,
2289                   "winceCreateLock2", zFilename);
2290       bLogged = TRUE;
2291       osCloseHandle(pFile->hShared);
2292       pFile->hShared = NULL;
2293     }
2294   }
2295 
2296   /* If shared memory could not be created, then close the mutex and fail */
2297   if( pFile->hShared==NULL ){
2298     if( !bLogged ){
2299       pFile->lastErrno = lastErrno;
2300       winLogError(SQLITE_IOERR, pFile->lastErrno,
2301                   "winceCreateLock3", zFilename);
2302       bLogged = TRUE;
2303     }
2304     winceMutexRelease(pFile->hMutex);
2305     osCloseHandle(pFile->hMutex);
2306     pFile->hMutex = NULL;
2307     return SQLITE_IOERR;
2308   }
2309 
2310   /* Initialize the shared memory if we're supposed to */
2311   if( bInit ){
2312     memset(pFile->shared, 0, sizeof(winceLock));
2313   }
2314 
2315   winceMutexRelease(pFile->hMutex);
2316   return SQLITE_OK;
2317 }
2318 
2319 /*
2320 ** Destroy the part of winFile that deals with wince locks
2321 */
2322 static void winceDestroyLock(winFile *pFile){
2323   if (pFile->hMutex){
2324     /* Acquire the mutex */
2325     winceMutexAcquire(pFile->hMutex);
2326 
2327     /* The following blocks should probably assert in debug mode, but they
2328        are to cleanup in case any locks remained open */
2329     if (pFile->local.nReaders){
2330       pFile->shared->nReaders --;
2331     }
2332     if (pFile->local.bReserved){
2333       pFile->shared->bReserved = FALSE;
2334     }
2335     if (pFile->local.bPending){
2336       pFile->shared->bPending = FALSE;
2337     }
2338     if (pFile->local.bExclusive){
2339       pFile->shared->bExclusive = FALSE;
2340     }
2341 
2342     /* De-reference and close our copy of the shared memory handle */
2343     osUnmapViewOfFile(pFile->shared);
2344     osCloseHandle(pFile->hShared);
2345 
2346     /* Done with the mutex */
2347     winceMutexRelease(pFile->hMutex);
2348     osCloseHandle(pFile->hMutex);
2349     pFile->hMutex = NULL;
2350   }
2351 }
2352 
2353 /*
2354 ** An implementation of the LockFile() API of Windows for CE
2355 */
2356 static BOOL winceLockFile(
2357   LPHANDLE phFile,
2358   DWORD dwFileOffsetLow,
2359   DWORD dwFileOffsetHigh,
2360   DWORD nNumberOfBytesToLockLow,
2361   DWORD nNumberOfBytesToLockHigh
2362 ){
2363   winFile *pFile = HANDLE_TO_WINFILE(phFile);
2364   BOOL bReturn = FALSE;
2365 
2366   UNUSED_PARAMETER(dwFileOffsetHigh);
2367   UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
2368 
2369   if (!pFile->hMutex) return TRUE;
2370   winceMutexAcquire(pFile->hMutex);
2371 
2372   /* Wanting an exclusive lock? */
2373   if (dwFileOffsetLow == (DWORD)SHARED_FIRST
2374        && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
2375     if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
2376        pFile->shared->bExclusive = TRUE;
2377        pFile->local.bExclusive = TRUE;
2378        bReturn = TRUE;
2379     }
2380   }
2381 
2382   /* Want a read-only lock? */
2383   else if (dwFileOffsetLow == (DWORD)SHARED_FIRST &&
2384            nNumberOfBytesToLockLow == 1){
2385     if (pFile->shared->bExclusive == 0){
2386       pFile->local.nReaders ++;
2387       if (pFile->local.nReaders == 1){
2388         pFile->shared->nReaders ++;
2389       }
2390       bReturn = TRUE;
2391     }
2392   }
2393 
2394   /* Want a pending lock? */
2395   else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
2396            && nNumberOfBytesToLockLow == 1){
2397     /* If no pending lock has been acquired, then acquire it */
2398     if (pFile->shared->bPending == 0) {
2399       pFile->shared->bPending = TRUE;
2400       pFile->local.bPending = TRUE;
2401       bReturn = TRUE;
2402     }
2403   }
2404 
2405   /* Want a reserved lock? */
2406   else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
2407            && nNumberOfBytesToLockLow == 1){
2408     if (pFile->shared->bReserved == 0) {
2409       pFile->shared->bReserved = TRUE;
2410       pFile->local.bReserved = TRUE;
2411       bReturn = TRUE;
2412     }
2413   }
2414 
2415   winceMutexRelease(pFile->hMutex);
2416   return bReturn;
2417 }
2418 
2419 /*
2420 ** An implementation of the UnlockFile API of Windows for CE
2421 */
2422 static BOOL winceUnlockFile(
2423   LPHANDLE phFile,
2424   DWORD dwFileOffsetLow,
2425   DWORD dwFileOffsetHigh,
2426   DWORD nNumberOfBytesToUnlockLow,
2427   DWORD nNumberOfBytesToUnlockHigh
2428 ){
2429   winFile *pFile = HANDLE_TO_WINFILE(phFile);
2430   BOOL bReturn = FALSE;
2431 
2432   UNUSED_PARAMETER(dwFileOffsetHigh);
2433   UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);
2434 
2435   if (!pFile->hMutex) return TRUE;
2436   winceMutexAcquire(pFile->hMutex);
2437 
2438   /* Releasing a reader lock or an exclusive lock */
2439   if (dwFileOffsetLow == (DWORD)SHARED_FIRST){
2440     /* Did we have an exclusive lock? */
2441     if (pFile->local.bExclusive){
2442       assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE);
2443       pFile->local.bExclusive = FALSE;
2444       pFile->shared->bExclusive = FALSE;
2445       bReturn = TRUE;
2446     }
2447 
2448     /* Did we just have a reader lock? */
2449     else if (pFile->local.nReaders){
2450       assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE
2451              || nNumberOfBytesToUnlockLow == 1);
2452       pFile->local.nReaders --;
2453       if (pFile->local.nReaders == 0)
2454       {
2455         pFile->shared->nReaders --;
2456       }
2457       bReturn = TRUE;
2458     }
2459   }
2460 
2461   /* Releasing a pending lock */
2462   else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
2463            && nNumberOfBytesToUnlockLow == 1){
2464     if (pFile->local.bPending){
2465       pFile->local.bPending = FALSE;
2466       pFile->shared->bPending = FALSE;
2467       bReturn = TRUE;
2468     }
2469   }
2470   /* Releasing a reserved lock */
2471   else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
2472            && nNumberOfBytesToUnlockLow == 1){
2473     if (pFile->local.bReserved) {
2474       pFile->local.bReserved = FALSE;
2475       pFile->shared->bReserved = FALSE;
2476       bReturn = TRUE;
2477     }
2478   }
2479 
2480   winceMutexRelease(pFile->hMutex);
2481   return bReturn;
2482 }
2483 /*
2484 ** End of the special code for wince
2485 *****************************************************************************/
2486 #endif /* SQLITE_OS_WINCE */
2487 
2488 /*
2489 ** Lock a file region.
2490 */
2491 static BOOL winLockFile(
2492   LPHANDLE phFile,
2493   DWORD flags,
2494   DWORD offsetLow,
2495   DWORD offsetHigh,
2496   DWORD numBytesLow,
2497   DWORD numBytesHigh
2498 ){
2499 #if SQLITE_OS_WINCE
2500   /*
2501   ** NOTE: Windows CE is handled differently here due its lack of the Win32
2502   **       API LockFile.
2503   */
2504   return winceLockFile(phFile, offsetLow, offsetHigh,
2505                        numBytesLow, numBytesHigh);
2506 #else
2507   if( osIsNT() ){
2508     OVERLAPPED ovlp;
2509     memset(&ovlp, 0, sizeof(OVERLAPPED));
2510     ovlp.Offset = offsetLow;
2511     ovlp.OffsetHigh = offsetHigh;
2512     return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
2513   }else{
2514     return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
2515                       numBytesHigh);
2516   }
2517 #endif
2518 }
2519 
2520 /*
2521 ** Unlock a file region.
2522  */
2523 static BOOL winUnlockFile(
2524   LPHANDLE phFile,
2525   DWORD offsetLow,
2526   DWORD offsetHigh,
2527   DWORD numBytesLow,
2528   DWORD numBytesHigh
2529 ){
2530 #if SQLITE_OS_WINCE
2531   /*
2532   ** NOTE: Windows CE is handled differently here due its lack of the Win32
2533   **       API UnlockFile.
2534   */
2535   return winceUnlockFile(phFile, offsetLow, offsetHigh,
2536                          numBytesLow, numBytesHigh);
2537 #else
2538   if( osIsNT() ){
2539     OVERLAPPED ovlp;
2540     memset(&ovlp, 0, sizeof(OVERLAPPED));
2541     ovlp.Offset = offsetLow;
2542     ovlp.OffsetHigh = offsetHigh;
2543     return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
2544   }else{
2545     return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
2546                         numBytesHigh);
2547   }
2548 #endif
2549 }
2550 
2551 /*****************************************************************************
2552 ** The next group of routines implement the I/O methods specified
2553 ** by the sqlite3_io_methods object.
2554 ******************************************************************************/
2555 
2556 /*
2557 ** Some Microsoft compilers lack this definition.
2558 */
2559 #ifndef INVALID_SET_FILE_POINTER
2560 # define INVALID_SET_FILE_POINTER ((DWORD)-1)
2561 #endif
2562 
2563 /*
2564 ** Move the current position of the file handle passed as the first
2565 ** argument to offset iOffset within the file. If successful, return 0.
2566 ** Otherwise, set pFile->lastErrno and return non-zero.
2567 */
2568 static int winSeekFile(winFile *pFile, sqlite3_int64 iOffset){
2569 #if !SQLITE_OS_WINRT
2570   LONG upperBits;                 /* Most sig. 32 bits of new offset */
2571   LONG lowerBits;                 /* Least sig. 32 bits of new offset */
2572   DWORD dwRet;                    /* Value returned by SetFilePointer() */
2573   DWORD lastErrno;                /* Value returned by GetLastError() */
2574 
2575   OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
2576 
2577   upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
2578   lowerBits = (LONG)(iOffset & 0xffffffff);
2579 
2580   /* API oddity: If successful, SetFilePointer() returns a dword
2581   ** containing the lower 32-bits of the new file-offset. Or, if it fails,
2582   ** it returns INVALID_SET_FILE_POINTER. However according to MSDN,
2583   ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine
2584   ** whether an error has actually occurred, it is also necessary to call
2585   ** GetLastError().
2586   */
2587   dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
2588 
2589   if( (dwRet==INVALID_SET_FILE_POINTER
2590       && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
2591     pFile->lastErrno = lastErrno;
2592     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
2593                 "winSeekFile", pFile->zPath);
2594     OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
2595     return 1;
2596   }
2597 
2598   OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
2599   return 0;
2600 #else
2601   /*
2602   ** Same as above, except that this implementation works for WinRT.
2603   */
2604 
2605   LARGE_INTEGER x;                /* The new offset */
2606   BOOL bRet;                      /* Value returned by SetFilePointerEx() */
2607 
2608   x.QuadPart = iOffset;
2609   bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);
2610 
2611   if(!bRet){
2612     pFile->lastErrno = osGetLastError();
2613     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
2614                 "winSeekFile", pFile->zPath);
2615     OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
2616     return 1;
2617   }
2618 
2619   OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
2620   return 0;
2621 #endif
2622 }
2623 
2624 #if SQLITE_MAX_MMAP_SIZE>0
2625 /* Forward references to VFS helper methods used for memory mapped files */
2626 static int winMapfile(winFile*, sqlite3_int64);
2627 static int winUnmapfile(winFile*);
2628 #endif
2629 
2630 /*
2631 ** Close a file.
2632 **
2633 ** It is reported that an attempt to close a handle might sometimes
2634 ** fail.  This is a very unreasonable result, but Windows is notorious
2635 ** for being unreasonable so I do not doubt that it might happen.  If
2636 ** the close fails, we pause for 100 milliseconds and try again.  As
2637 ** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
2638 ** giving up and returning an error.
2639 */
2640 #define MX_CLOSE_ATTEMPT 3
2641 static int winClose(sqlite3_file *id){
2642   int rc, cnt = 0;
2643   winFile *pFile = (winFile*)id;
2644 
2645   assert( id!=0 );
2646 #ifndef SQLITE_OMIT_WAL
2647   assert( pFile->pShm==0 );
2648 #endif
2649   assert( pFile->h!=NULL && pFile->h!=INVALID_HANDLE_VALUE );
2650   OSTRACE(("CLOSE pid=%lu, pFile=%p, file=%p\n",
2651            osGetCurrentProcessId(), pFile, pFile->h));
2652 
2653 #if SQLITE_MAX_MMAP_SIZE>0
2654   winUnmapfile(pFile);
2655 #endif
2656 
2657   do{
2658     rc = osCloseHandle(pFile->h);
2659     /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
2660   }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (sqlite3_win32_sleep(100), 1) );
2661 #if SQLITE_OS_WINCE
2662 #define WINCE_DELETION_ATTEMPTS 3
2663   {
2664     winVfsAppData *pAppData = (winVfsAppData*)pFile->pVfs->pAppData;
2665     if( pAppData==NULL || !pAppData->bNoLock ){
2666       winceDestroyLock(pFile);
2667     }
2668   }
2669   if( pFile->zDeleteOnClose ){
2670     int cnt = 0;
2671     while(
2672            osDeleteFileW(pFile->zDeleteOnClose)==0
2673         && osGetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff
2674         && cnt++ < WINCE_DELETION_ATTEMPTS
2675     ){
2676        sqlite3_win32_sleep(100);  /* Wait a little before trying again */
2677     }
2678     sqlite3_free(pFile->zDeleteOnClose);
2679   }
2680 #endif
2681   if( rc ){
2682     pFile->h = NULL;
2683   }
2684   OpenCounter(-1);
2685   OSTRACE(("CLOSE pid=%lu, pFile=%p, file=%p, rc=%s\n",
2686            osGetCurrentProcessId(), pFile, pFile->h, rc ? "ok" : "failed"));
2687   return rc ? SQLITE_OK
2688             : winLogError(SQLITE_IOERR_CLOSE, osGetLastError(),
2689                           "winClose", pFile->zPath);
2690 }
2691 
2692 /*
2693 ** Read data from a file into a buffer.  Return SQLITE_OK if all
2694 ** bytes were read successfully and SQLITE_IOERR if anything goes
2695 ** wrong.
2696 */
2697 static int winRead(
2698   sqlite3_file *id,          /* File to read from */
2699   void *pBuf,                /* Write content into this buffer */
2700   int amt,                   /* Number of bytes to read */
2701   sqlite3_int64 offset       /* Begin reading at this offset */
2702 ){
2703 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2704   OVERLAPPED overlapped;          /* The offset for ReadFile. */
2705 #endif
2706   winFile *pFile = (winFile*)id;  /* file handle */
2707   DWORD nRead;                    /* Number of bytes actually read from file */
2708   int nRetry = 0;                 /* Number of retrys */
2709 
2710   assert( id!=0 );
2711   assert( amt>0 );
2712   assert( offset>=0 );
2713   SimulateIOError(return SQLITE_IOERR_READ);
2714   OSTRACE(("READ pid=%lu, pFile=%p, file=%p, buffer=%p, amount=%d, "
2715            "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
2716            pFile->h, pBuf, amt, offset, pFile->locktype));
2717 
2718 #if SQLITE_MAX_MMAP_SIZE>0
2719   /* Deal with as much of this read request as possible by transfering
2720   ** data from the memory mapping using memcpy().  */
2721   if( offset<pFile->mmapSize ){
2722     if( offset+amt <= pFile->mmapSize ){
2723       memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
2724       OSTRACE(("READ-MMAP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2725                osGetCurrentProcessId(), pFile, pFile->h));
2726       return SQLITE_OK;
2727     }else{
2728       int nCopy = (int)(pFile->mmapSize - offset);
2729       memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
2730       pBuf = &((u8 *)pBuf)[nCopy];
2731       amt -= nCopy;
2732       offset += nCopy;
2733     }
2734   }
2735 #endif
2736 
2737 #if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
2738   if( winSeekFile(pFile, offset) ){
2739     OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_FULL\n",
2740              osGetCurrentProcessId(), pFile, pFile->h));
2741     return SQLITE_FULL;
2742   }
2743   while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
2744 #else
2745   memset(&overlapped, 0, sizeof(OVERLAPPED));
2746   overlapped.Offset = (LONG)(offset & 0xffffffff);
2747   overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2748   while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
2749          osGetLastError()!=ERROR_HANDLE_EOF ){
2750 #endif
2751     DWORD lastErrno;
2752     if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
2753     pFile->lastErrno = lastErrno;
2754     OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_READ\n",
2755              osGetCurrentProcessId(), pFile, pFile->h));
2756     return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
2757                        "winRead", pFile->zPath);
2758   }
2759   winLogIoerr(nRetry, __LINE__);
2760   if( nRead<(DWORD)amt ){
2761     /* Unread parts of the buffer must be zero-filled */
2762     memset(&((char*)pBuf)[nRead], 0, amt-nRead);
2763     OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_SHORT_READ\n",
2764              osGetCurrentProcessId(), pFile, pFile->h));
2765     return SQLITE_IOERR_SHORT_READ;
2766   }
2767 
2768   OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2769            osGetCurrentProcessId(), pFile, pFile->h));
2770   return SQLITE_OK;
2771 }
2772 
2773 /*
2774 ** Write data from a buffer into a file.  Return SQLITE_OK on success
2775 ** or some other error code on failure.
2776 */
2777 static int winWrite(
2778   sqlite3_file *id,               /* File to write into */
2779   const void *pBuf,               /* The bytes to be written */
2780   int amt,                        /* Number of bytes to write */
2781   sqlite3_int64 offset            /* Offset into the file to begin writing at */
2782 ){
2783   int rc = 0;                     /* True if error has occurred, else false */
2784   winFile *pFile = (winFile*)id;  /* File handle */
2785   int nRetry = 0;                 /* Number of retries */
2786 
2787   assert( amt>0 );
2788   assert( pFile );
2789   SimulateIOError(return SQLITE_IOERR_WRITE);
2790   SimulateDiskfullError(return SQLITE_FULL);
2791 
2792   OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, buffer=%p, amount=%d, "
2793            "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
2794            pFile->h, pBuf, amt, offset, pFile->locktype));
2795 
2796 #if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
2797   /* Deal with as much of this write request as possible by transfering
2798   ** data from the memory mapping using memcpy().  */
2799   if( offset<pFile->mmapSize ){
2800     if( offset+amt <= pFile->mmapSize ){
2801       memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
2802       OSTRACE(("WRITE-MMAP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2803                osGetCurrentProcessId(), pFile, pFile->h));
2804       return SQLITE_OK;
2805     }else{
2806       int nCopy = (int)(pFile->mmapSize - offset);
2807       memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
2808       pBuf = &((u8 *)pBuf)[nCopy];
2809       amt -= nCopy;
2810       offset += nCopy;
2811     }
2812   }
2813 #endif
2814 
2815 #if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
2816   rc = winSeekFile(pFile, offset);
2817   if( rc==0 ){
2818 #else
2819   {
2820 #endif
2821 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2822     OVERLAPPED overlapped;        /* The offset for WriteFile. */
2823 #endif
2824     u8 *aRem = (u8 *)pBuf;        /* Data yet to be written */
2825     int nRem = amt;               /* Number of bytes yet to be written */
2826     DWORD nWrite;                 /* Bytes written by each WriteFile() call */
2827     DWORD lastErrno = NO_ERROR;   /* Value returned by GetLastError() */
2828 
2829 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2830     memset(&overlapped, 0, sizeof(OVERLAPPED));
2831     overlapped.Offset = (LONG)(offset & 0xffffffff);
2832     overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2833 #endif
2834 
2835     while( nRem>0 ){
2836 #if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
2837       if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
2838 #else
2839       if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
2840 #endif
2841         if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
2842         break;
2843       }
2844       assert( nWrite==0 || nWrite<=(DWORD)nRem );
2845       if( nWrite==0 || nWrite>(DWORD)nRem ){
2846         lastErrno = osGetLastError();
2847         break;
2848       }
2849 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2850       offset += nWrite;
2851       overlapped.Offset = (LONG)(offset & 0xffffffff);
2852       overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2853 #endif
2854       aRem += nWrite;
2855       nRem -= nWrite;
2856     }
2857     if( nRem>0 ){
2858       pFile->lastErrno = lastErrno;
2859       rc = 1;
2860     }
2861   }
2862 
2863   if( rc ){
2864     if(   ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
2865        || ( pFile->lastErrno==ERROR_DISK_FULL )){
2866       OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_FULL\n",
2867                osGetCurrentProcessId(), pFile, pFile->h));
2868       return winLogError(SQLITE_FULL, pFile->lastErrno,
2869                          "winWrite1", pFile->zPath);
2870     }
2871     OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_WRITE\n",
2872              osGetCurrentProcessId(), pFile, pFile->h));
2873     return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
2874                        "winWrite2", pFile->zPath);
2875   }else{
2876     winLogIoerr(nRetry, __LINE__);
2877   }
2878   OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2879            osGetCurrentProcessId(), pFile, pFile->h));
2880   return SQLITE_OK;
2881 }
2882 
2883 /*
2884 ** Truncate an open file to a specified size
2885 */
2886 static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
2887   winFile *pFile = (winFile*)id;  /* File handle object */
2888   int rc = SQLITE_OK;             /* Return code for this function */
2889   DWORD lastErrno;
2890 
2891   assert( pFile );
2892   SimulateIOError(return SQLITE_IOERR_TRUNCATE);
2893   OSTRACE(("TRUNCATE pid=%lu, pFile=%p, file=%p, size=%lld, lock=%d\n",
2894            osGetCurrentProcessId(), pFile, pFile->h, nByte, pFile->locktype));
2895 
2896   /* If the user has configured a chunk-size for this file, truncate the
2897   ** file so that it consists of an integer number of chunks (i.e. the
2898   ** actual file size after the operation may be larger than the requested
2899   ** size).
2900   */
2901   if( pFile->szChunk>0 ){
2902     nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
2903   }
2904 
2905   /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
2906   if( winSeekFile(pFile, nByte) ){
2907     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
2908                      "winTruncate1", pFile->zPath);
2909   }else if( 0==osSetEndOfFile(pFile->h) &&
2910             ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
2911     pFile->lastErrno = lastErrno;
2912     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
2913                      "winTruncate2", pFile->zPath);
2914   }
2915 
2916 #if SQLITE_MAX_MMAP_SIZE>0
2917   /* If the file was truncated to a size smaller than the currently
2918   ** mapped region, reduce the effective mapping size as well. SQLite will
2919   ** use read() and write() to access data beyond this point from now on.
2920   */
2921   if( pFile->pMapRegion && nByte<pFile->mmapSize ){
2922     pFile->mmapSize = nByte;
2923   }
2924 #endif
2925 
2926   OSTRACE(("TRUNCATE pid=%lu, pFile=%p, file=%p, rc=%s\n",
2927            osGetCurrentProcessId(), pFile, pFile->h, sqlite3ErrName(rc)));
2928   return rc;
2929 }
2930 
2931 #ifdef SQLITE_TEST
2932 /*
2933 ** Count the number of fullsyncs and normal syncs.  This is used to test
2934 ** that syncs and fullsyncs are occuring at the right times.
2935 */
2936 int sqlite3_sync_count = 0;
2937 int sqlite3_fullsync_count = 0;
2938 #endif
2939 
2940 /*
2941 ** Make sure all writes to a particular file are committed to disk.
2942 */
2943 static int winSync(sqlite3_file *id, int flags){
2944 #ifndef SQLITE_NO_SYNC
2945   /*
2946   ** Used only when SQLITE_NO_SYNC is not defined.
2947    */
2948   BOOL rc;
2949 #endif
2950 #if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || \
2951     defined(SQLITE_HAVE_OS_TRACE)
2952   /*
2953   ** Used when SQLITE_NO_SYNC is not defined and by the assert() and/or
2954   ** OSTRACE() macros.
2955    */
2956   winFile *pFile = (winFile*)id;
2957 #else
2958   UNUSED_PARAMETER(id);
2959 #endif
2960 
2961   assert( pFile );
2962   /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
2963   assert((flags&0x0F)==SQLITE_SYNC_NORMAL
2964       || (flags&0x0F)==SQLITE_SYNC_FULL
2965   );
2966 
2967   /* Unix cannot, but some systems may return SQLITE_FULL from here. This
2968   ** line is to test that doing so does not cause any problems.
2969   */
2970   SimulateDiskfullError( return SQLITE_FULL );
2971 
2972   OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, flags=%x, lock=%d\n",
2973            osGetCurrentProcessId(), pFile, pFile->h, flags,
2974            pFile->locktype));
2975 
2976 #ifndef SQLITE_TEST
2977   UNUSED_PARAMETER(flags);
2978 #else
2979   if( (flags&0x0F)==SQLITE_SYNC_FULL ){
2980     sqlite3_fullsync_count++;
2981   }
2982   sqlite3_sync_count++;
2983 #endif
2984 
2985   /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
2986   ** no-op
2987   */
2988 #ifdef SQLITE_NO_SYNC
2989   OSTRACE(("SYNC-NOP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2990            osGetCurrentProcessId(), pFile, pFile->h));
2991   return SQLITE_OK;
2992 #else
2993 #if SQLITE_MAX_MMAP_SIZE>0
2994   if( pFile->pMapRegion ){
2995     if( osFlushViewOfFile(pFile->pMapRegion, 0) ){
2996       OSTRACE(("SYNC-MMAP pid=%lu, pFile=%p, pMapRegion=%p, "
2997                "rc=SQLITE_OK\n", osGetCurrentProcessId(),
2998                pFile, pFile->pMapRegion));
2999     }else{
3000       pFile->lastErrno = osGetLastError();
3001       OSTRACE(("SYNC-MMAP pid=%lu, pFile=%p, pMapRegion=%p, "
3002                "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(),
3003                pFile, pFile->pMapRegion));
3004       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
3005                          "winSync1", pFile->zPath);
3006     }
3007   }
3008 #endif
3009   rc = osFlushFileBuffers(pFile->h);
3010   SimulateIOError( rc=FALSE );
3011   if( rc ){
3012     OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
3013              osGetCurrentProcessId(), pFile, pFile->h));
3014     return SQLITE_OK;
3015   }else{
3016     pFile->lastErrno = osGetLastError();
3017     OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_FSYNC\n",
3018              osGetCurrentProcessId(), pFile, pFile->h));
3019     return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
3020                        "winSync2", pFile->zPath);
3021   }
3022 #endif
3023 }
3024 
3025 /*
3026 ** Determine the current size of a file in bytes
3027 */
3028 static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
3029   winFile *pFile = (winFile*)id;
3030   int rc = SQLITE_OK;
3031 
3032   assert( id!=0 );
3033   assert( pSize!=0 );
3034   SimulateIOError(return SQLITE_IOERR_FSTAT);
3035   OSTRACE(("SIZE file=%p, pSize=%p\n", pFile->h, pSize));
3036 
3037 #if SQLITE_OS_WINRT
3038   {
3039     FILE_STANDARD_INFO info;
3040     if( osGetFileInformationByHandleEx(pFile->h, FileStandardInfo,
3041                                      &info, sizeof(info)) ){
3042       *pSize = info.EndOfFile.QuadPart;
3043     }else{
3044       pFile->lastErrno = osGetLastError();
3045       rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
3046                        "winFileSize", pFile->zPath);
3047     }
3048   }
3049 #else
3050   {
3051     DWORD upperBits;
3052     DWORD lowerBits;
3053     DWORD lastErrno;
3054 
3055     lowerBits = osGetFileSize(pFile->h, &upperBits);
3056     *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
3057     if(   (lowerBits == INVALID_FILE_SIZE)
3058        && ((lastErrno = osGetLastError())!=NO_ERROR) ){
3059       pFile->lastErrno = lastErrno;
3060       rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
3061                        "winFileSize", pFile->zPath);
3062     }
3063   }
3064 #endif
3065   OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
3066            pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
3067   return rc;
3068 }
3069 
3070 /*
3071 ** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
3072 */
3073 #ifndef LOCKFILE_FAIL_IMMEDIATELY
3074 # define LOCKFILE_FAIL_IMMEDIATELY 1
3075 #endif
3076 
3077 #ifndef LOCKFILE_EXCLUSIVE_LOCK
3078 # define LOCKFILE_EXCLUSIVE_LOCK 2
3079 #endif
3080 
3081 /*
3082 ** Historically, SQLite has used both the LockFile and LockFileEx functions.
3083 ** When the LockFile function was used, it was always expected to fail
3084 ** immediately if the lock could not be obtained.  Also, it always expected to
3085 ** obtain an exclusive lock.  These flags are used with the LockFileEx function
3086 ** and reflect those expectations; therefore, they should not be changed.
3087 */
3088 #ifndef SQLITE_LOCKFILE_FLAGS
3089 # define SQLITE_LOCKFILE_FLAGS   (LOCKFILE_FAIL_IMMEDIATELY | \
3090                                   LOCKFILE_EXCLUSIVE_LOCK)
3091 #endif
3092 
3093 /*
3094 ** Currently, SQLite never calls the LockFileEx function without wanting the
3095 ** call to fail immediately if the lock cannot be obtained.
3096 */
3097 #ifndef SQLITE_LOCKFILEEX_FLAGS
3098 # define SQLITE_LOCKFILEEX_FLAGS (LOCKFILE_FAIL_IMMEDIATELY)
3099 #endif
3100 
3101 /*
3102 ** Acquire a reader lock.
3103 ** Different API routines are called depending on whether or not this
3104 ** is Win9x or WinNT.
3105 */
3106 static int winGetReadLock(winFile *pFile){
3107   int res;
3108   OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
3109   if( osIsNT() ){
3110 #if SQLITE_OS_WINCE
3111     /*
3112     ** NOTE: Windows CE is handled differently here due its lack of the Win32
3113     **       API LockFileEx.
3114     */
3115     res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
3116 #else
3117     res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS, SHARED_FIRST, 0,
3118                       SHARED_SIZE, 0);
3119 #endif
3120   }
3121 #ifdef SQLITE_WIN32_HAS_ANSI
3122   else{
3123     int lk;
3124     sqlite3_randomness(sizeof(lk), &lk);
3125     pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
3126     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
3127                       SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
3128   }
3129 #endif
3130   if( res == 0 ){
3131     pFile->lastErrno = osGetLastError();
3132     /* No need to log a failure to lock */
3133   }
3134   OSTRACE(("READ-LOCK file=%p, result=%d\n", pFile->h, res));
3135   return res;
3136 }
3137 
3138 /*
3139 ** Undo a readlock
3140 */
3141 static int winUnlockReadLock(winFile *pFile){
3142   int res;
3143   DWORD lastErrno;
3144   OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
3145   if( osIsNT() ){
3146     res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
3147   }
3148 #ifdef SQLITE_WIN32_HAS_ANSI
3149   else{
3150     res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
3151   }
3152 #endif
3153   if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
3154     pFile->lastErrno = lastErrno;
3155     winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
3156                 "winUnlockReadLock", pFile->zPath);
3157   }
3158   OSTRACE(("READ-UNLOCK file=%p, result=%d\n", pFile->h, res));
3159   return res;
3160 }
3161 
3162 /*
3163 ** Lock the file with the lock specified by parameter locktype - one
3164 ** of the following:
3165 **
3166 **     (1) SHARED_LOCK
3167 **     (2) RESERVED_LOCK
3168 **     (3) PENDING_LOCK
3169 **     (4) EXCLUSIVE_LOCK
3170 **
3171 ** Sometimes when requesting one lock state, additional lock states
3172 ** are inserted in between.  The locking might fail on one of the later
3173 ** transitions leaving the lock state different from what it started but
3174 ** still short of its goal.  The following chart shows the allowed
3175 ** transitions and the inserted intermediate states:
3176 **
3177 **    UNLOCKED -> SHARED
3178 **    SHARED -> RESERVED
3179 **    SHARED -> (PENDING) -> EXCLUSIVE
3180 **    RESERVED -> (PENDING) -> EXCLUSIVE
3181 **    PENDING -> EXCLUSIVE
3182 **
3183 ** This routine will only increase a lock.  The winUnlock() routine
3184 ** erases all locks at once and returns us immediately to locking level 0.
3185 ** It is not possible to lower the locking level one step at a time.  You
3186 ** must go straight to locking level 0.
3187 */
3188 static int winLock(sqlite3_file *id, int locktype){
3189   int rc = SQLITE_OK;    /* Return code from subroutines */
3190   int res = 1;           /* Result of a Windows lock call */
3191   int newLocktype;       /* Set pFile->locktype to this value before exiting */
3192   int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
3193   winFile *pFile = (winFile*)id;
3194   DWORD lastErrno = NO_ERROR;
3195 
3196   assert( id!=0 );
3197   OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
3198            pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
3199 
3200   /* If there is already a lock of this type or more restrictive on the
3201   ** OsFile, do nothing. Don't use the end_lock: exit path, as
3202   ** sqlite3OsEnterMutex() hasn't been called yet.
3203   */
3204   if( pFile->locktype>=locktype ){
3205     OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
3206     return SQLITE_OK;
3207   }
3208 
3209   /* Do not allow any kind of write-lock on a read-only database
3210   */
3211   if( (pFile->ctrlFlags & WINFILE_RDONLY)!=0 && locktype>=RESERVED_LOCK ){
3212     return SQLITE_IOERR_LOCK;
3213   }
3214 
3215   /* Make sure the locking sequence is correct
3216   */
3217   assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
3218   assert( locktype!=PENDING_LOCK );
3219   assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
3220 
3221   /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
3222   ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
3223   ** the PENDING_LOCK byte is temporary.
3224   */
3225   newLocktype = pFile->locktype;
3226   if( pFile->locktype==NO_LOCK
3227    || (locktype==EXCLUSIVE_LOCK && pFile->locktype<=RESERVED_LOCK)
3228   ){
3229     int cnt = 3;
3230     while( cnt-->0 && (res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
3231                                          PENDING_BYTE, 0, 1, 0))==0 ){
3232       /* Try 3 times to get the pending lock.  This is needed to work
3233       ** around problems caused by indexing and/or anti-virus software on
3234       ** Windows systems.
3235       ** If you are using this code as a model for alternative VFSes, do not
3236       ** copy this retry logic.  It is a hack intended for Windows only.
3237       */
3238       lastErrno = osGetLastError();
3239       OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, result=%d\n",
3240                pFile->h, cnt, res));
3241       if( lastErrno==ERROR_INVALID_HANDLE ){
3242         pFile->lastErrno = lastErrno;
3243         rc = SQLITE_IOERR_LOCK;
3244         OSTRACE(("LOCK-FAIL file=%p, count=%d, rc=%s\n",
3245                  pFile->h, cnt, sqlite3ErrName(rc)));
3246         return rc;
3247       }
3248       if( cnt ) sqlite3_win32_sleep(1);
3249     }
3250     gotPendingLock = res;
3251     if( !res ){
3252       lastErrno = osGetLastError();
3253     }
3254   }
3255 
3256   /* Acquire a shared lock
3257   */
3258   if( locktype==SHARED_LOCK && res ){
3259     assert( pFile->locktype==NO_LOCK );
3260     res = winGetReadLock(pFile);
3261     if( res ){
3262       newLocktype = SHARED_LOCK;
3263     }else{
3264       lastErrno = osGetLastError();
3265     }
3266   }
3267 
3268   /* Acquire a RESERVED lock
3269   */
3270   if( locktype==RESERVED_LOCK && res ){
3271     assert( pFile->locktype==SHARED_LOCK );
3272     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, RESERVED_BYTE, 0, 1, 0);
3273     if( res ){
3274       newLocktype = RESERVED_LOCK;
3275     }else{
3276       lastErrno = osGetLastError();
3277     }
3278   }
3279 
3280   /* Acquire a PENDING lock
3281   */
3282   if( locktype==EXCLUSIVE_LOCK && res ){
3283     newLocktype = PENDING_LOCK;
3284     gotPendingLock = 0;
3285   }
3286 
3287   /* Acquire an EXCLUSIVE lock
3288   */
3289   if( locktype==EXCLUSIVE_LOCK && res ){
3290     assert( pFile->locktype>=SHARED_LOCK );
3291     res = winUnlockReadLock(pFile);
3292     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
3293                       SHARED_SIZE, 0);
3294     if( res ){
3295       newLocktype = EXCLUSIVE_LOCK;
3296     }else{
3297       lastErrno = osGetLastError();
3298       winGetReadLock(pFile);
3299     }
3300   }
3301 
3302   /* If we are holding a PENDING lock that ought to be released, then
3303   ** release it now.
3304   */
3305   if( gotPendingLock && locktype==SHARED_LOCK ){
3306     winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
3307   }
3308 
3309   /* Update the state of the lock has held in the file descriptor then
3310   ** return the appropriate result code.
3311   */
3312   if( res ){
3313     rc = SQLITE_OK;
3314   }else{
3315     pFile->lastErrno = lastErrno;
3316     rc = SQLITE_BUSY;
3317     OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
3318              pFile->h, locktype, newLocktype));
3319   }
3320   pFile->locktype = (u8)newLocktype;
3321   OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
3322            pFile->h, pFile->locktype, sqlite3ErrName(rc)));
3323   return rc;
3324 }
3325 
3326 /*
3327 ** This routine checks if there is a RESERVED lock held on the specified
3328 ** file by this or any other process. If such a lock is held, return
3329 ** non-zero, otherwise zero.
3330 */
3331 static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
3332   int res;
3333   winFile *pFile = (winFile*)id;
3334 
3335   SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
3336   OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));
3337 
3338   assert( id!=0 );
3339   if( pFile->locktype>=RESERVED_LOCK ){
3340     res = 1;
3341     OSTRACE(("TEST-WR-LOCK file=%p, result=%d (local)\n", pFile->h, res));
3342   }else{
3343     res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE,0,1,0);
3344     if( res ){
3345       winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
3346     }
3347     res = !res;
3348     OSTRACE(("TEST-WR-LOCK file=%p, result=%d (remote)\n", pFile->h, res));
3349   }
3350   *pResOut = res;
3351   OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
3352            pFile->h, pResOut, *pResOut));
3353   return SQLITE_OK;
3354 }
3355 
3356 /*
3357 ** Lower the locking level on file descriptor id to locktype.  locktype
3358 ** must be either NO_LOCK or SHARED_LOCK.
3359 **
3360 ** If the locking level of the file descriptor is already at or below
3361 ** the requested locking level, this routine is a no-op.
3362 **
3363 ** It is not possible for this routine to fail if the second argument
3364 ** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
3365 ** might return SQLITE_IOERR;
3366 */
3367 static int winUnlock(sqlite3_file *id, int locktype){
3368   int type;
3369   winFile *pFile = (winFile*)id;
3370   int rc = SQLITE_OK;
3371   assert( pFile!=0 );
3372   assert( locktype<=SHARED_LOCK );
3373   OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
3374            pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
3375   type = pFile->locktype;
3376   if( type>=EXCLUSIVE_LOCK ){
3377     winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
3378     if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
3379       /* This should never happen.  We should always be able to
3380       ** reacquire the read lock */
3381       rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
3382                        "winUnlock", pFile->zPath);
3383     }
3384   }
3385   if( type>=RESERVED_LOCK ){
3386     winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
3387   }
3388   if( locktype==NO_LOCK && type>=SHARED_LOCK ){
3389     winUnlockReadLock(pFile);
3390   }
3391   if( type>=PENDING_LOCK ){
3392     winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
3393   }
3394   pFile->locktype = (u8)locktype;
3395   OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
3396            pFile->h, pFile->locktype, sqlite3ErrName(rc)));
3397   return rc;
3398 }
3399 
3400 /******************************************************************************
3401 ****************************** No-op Locking **********************************
3402 **
3403 ** Of the various locking implementations available, this is by far the
3404 ** simplest:  locking is ignored.  No attempt is made to lock the database
3405 ** file for reading or writing.
3406 **
3407 ** This locking mode is appropriate for use on read-only databases
3408 ** (ex: databases that are burned into CD-ROM, for example.)  It can
3409 ** also be used if the application employs some external mechanism to
3410 ** prevent simultaneous access of the same database by two or more
3411 ** database connections.  But there is a serious risk of database
3412 ** corruption if this locking mode is used in situations where multiple
3413 ** database connections are accessing the same database file at the same
3414 ** time and one or more of those connections are writing.
3415 */
3416 
3417 static int winNolockLock(sqlite3_file *id, int locktype){
3418   UNUSED_PARAMETER(id);
3419   UNUSED_PARAMETER(locktype);
3420   return SQLITE_OK;
3421 }
3422 
3423 static int winNolockCheckReservedLock(sqlite3_file *id, int *pResOut){
3424   UNUSED_PARAMETER(id);
3425   UNUSED_PARAMETER(pResOut);
3426   return SQLITE_OK;
3427 }
3428 
3429 static int winNolockUnlock(sqlite3_file *id, int locktype){
3430   UNUSED_PARAMETER(id);
3431   UNUSED_PARAMETER(locktype);
3432   return SQLITE_OK;
3433 }
3434 
3435 /******************* End of the no-op lock implementation *********************
3436 ******************************************************************************/
3437 
3438 /*
3439 ** If *pArg is initially negative then this is a query.  Set *pArg to
3440 ** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
3441 **
3442 ** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
3443 */
3444 static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
3445   if( *pArg<0 ){
3446     *pArg = (pFile->ctrlFlags & mask)!=0;
3447   }else if( (*pArg)==0 ){
3448     pFile->ctrlFlags &= ~mask;
3449   }else{
3450     pFile->ctrlFlags |= mask;
3451   }
3452 }
3453 
3454 /* Forward references to VFS helper methods used for temporary files */
3455 static int winGetTempname(sqlite3_vfs *, char **);
3456 static int winIsDir(const void *);
3457 static BOOL winIsDriveLetterAndColon(const char *);
3458 
3459 /*
3460 ** Control and query of the open file handle.
3461 */
3462 static int winFileControl(sqlite3_file *id, int op, void *pArg){
3463   winFile *pFile = (winFile*)id;
3464   OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
3465   switch( op ){
3466     case SQLITE_FCNTL_LOCKSTATE: {
3467       *(int*)pArg = pFile->locktype;
3468       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3469       return SQLITE_OK;
3470     }
3471     case SQLITE_FCNTL_LAST_ERRNO: {
3472       *(int*)pArg = (int)pFile->lastErrno;
3473       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3474       return SQLITE_OK;
3475     }
3476     case SQLITE_FCNTL_CHUNK_SIZE: {
3477       pFile->szChunk = *(int *)pArg;
3478       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3479       return SQLITE_OK;
3480     }
3481     case SQLITE_FCNTL_SIZE_HINT: {
3482       if( pFile->szChunk>0 ){
3483         sqlite3_int64 oldSz;
3484         int rc = winFileSize(id, &oldSz);
3485         if( rc==SQLITE_OK ){
3486           sqlite3_int64 newSz = *(sqlite3_int64*)pArg;
3487           if( newSz>oldSz ){
3488             SimulateIOErrorBenign(1);
3489             rc = winTruncate(id, newSz);
3490             SimulateIOErrorBenign(0);
3491           }
3492         }
3493         OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3494         return rc;
3495       }
3496       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3497       return SQLITE_OK;
3498     }
3499     case SQLITE_FCNTL_PERSIST_WAL: {
3500       winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
3501       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3502       return SQLITE_OK;
3503     }
3504     case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
3505       winModeBit(pFile, WINFILE_PSOW, (int*)pArg);
3506       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3507       return SQLITE_OK;
3508     }
3509     case SQLITE_FCNTL_VFSNAME: {
3510       *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
3511       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3512       return SQLITE_OK;
3513     }
3514     case SQLITE_FCNTL_WIN32_AV_RETRY: {
3515       int *a = (int*)pArg;
3516       if( a[0]>0 ){
3517         winIoerrRetry = a[0];
3518       }else{
3519         a[0] = winIoerrRetry;
3520       }
3521       if( a[1]>0 ){
3522         winIoerrRetryDelay = a[1];
3523       }else{
3524         a[1] = winIoerrRetryDelay;
3525       }
3526       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3527       return SQLITE_OK;
3528     }
3529     case SQLITE_FCNTL_WIN32_GET_HANDLE: {
3530       LPHANDLE phFile = (LPHANDLE)pArg;
3531       *phFile = pFile->h;
3532       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3533       return SQLITE_OK;
3534     }
3535 #ifdef SQLITE_TEST
3536     case SQLITE_FCNTL_WIN32_SET_HANDLE: {
3537       LPHANDLE phFile = (LPHANDLE)pArg;
3538       HANDLE hOldFile = pFile->h;
3539       pFile->h = *phFile;
3540       *phFile = hOldFile;
3541       OSTRACE(("FCNTL oldFile=%p, newFile=%p, rc=SQLITE_OK\n",
3542                hOldFile, pFile->h));
3543       return SQLITE_OK;
3544     }
3545 #endif
3546     case SQLITE_FCNTL_TEMPFILENAME: {
3547       char *zTFile = 0;
3548       int rc = winGetTempname(pFile->pVfs, &zTFile);
3549       if( rc==SQLITE_OK ){
3550         *(char**)pArg = zTFile;
3551       }
3552       OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3553       return rc;
3554     }
3555 #if SQLITE_MAX_MMAP_SIZE>0
3556     case SQLITE_FCNTL_MMAP_SIZE: {
3557       i64 newLimit = *(i64*)pArg;
3558       int rc = SQLITE_OK;
3559       if( newLimit>sqlite3GlobalConfig.mxMmap ){
3560         newLimit = sqlite3GlobalConfig.mxMmap;
3561       }
3562 
3563       /* The value of newLimit may be eventually cast to (SIZE_T) and passed
3564       ** to MapViewOfFile(). Restrict its value to 2GB if (SIZE_T) is not at
3565       ** least a 64-bit type. */
3566       if( newLimit>0 && sizeof(SIZE_T)<8 ){
3567         newLimit = (newLimit & 0x7FFFFFFF);
3568       }
3569 
3570       *(i64*)pArg = pFile->mmapSizeMax;
3571       if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
3572         pFile->mmapSizeMax = newLimit;
3573         if( pFile->mmapSize>0 ){
3574           winUnmapfile(pFile);
3575           rc = winMapfile(pFile, -1);
3576         }
3577       }
3578       OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3579       return rc;
3580     }
3581 #endif
3582   }
3583   OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
3584   return SQLITE_NOTFOUND;
3585 }
3586 
3587 /*
3588 ** Return the sector size in bytes of the underlying block device for
3589 ** the specified file. This is almost always 512 bytes, but may be
3590 ** larger for some devices.
3591 **
3592 ** SQLite code assumes this function cannot fail. It also assumes that
3593 ** if two files are created in the same file-system directory (i.e.
3594 ** a database and its journal file) that the sector size will be the
3595 ** same for both.
3596 */
3597 static int winSectorSize(sqlite3_file *id){
3598   (void)id;
3599   return SQLITE_DEFAULT_SECTOR_SIZE;
3600 }
3601 
3602 /*
3603 ** Return a vector of device characteristics.
3604 */
3605 static int winDeviceCharacteristics(sqlite3_file *id){
3606   winFile *p = (winFile*)id;
3607   return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
3608          ((p->ctrlFlags & WINFILE_PSOW)?SQLITE_IOCAP_POWERSAFE_OVERWRITE:0);
3609 }
3610 
3611 /*
3612 ** Windows will only let you create file view mappings
3613 ** on allocation size granularity boundaries.
3614 ** During sqlite3_os_init() we do a GetSystemInfo()
3615 ** to get the granularity size.
3616 */
3617 static SYSTEM_INFO winSysInfo;
3618 
3619 #ifndef SQLITE_OMIT_WAL
3620 
3621 /*
3622 ** Helper functions to obtain and relinquish the global mutex. The
3623 ** global mutex is used to protect the winLockInfo objects used by
3624 ** this file, all of which may be shared by multiple threads.
3625 **
3626 ** Function winShmMutexHeld() is used to assert() that the global mutex
3627 ** is held when required. This function is only used as part of assert()
3628 ** statements. e.g.
3629 **
3630 **   winShmEnterMutex()
3631 **     assert( winShmMutexHeld() );
3632 **   winShmLeaveMutex()
3633 */
3634 static void winShmEnterMutex(void){
3635   sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
3636 }
3637 static void winShmLeaveMutex(void){
3638   sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
3639 }
3640 #ifndef NDEBUG
3641 static int winShmMutexHeld(void) {
3642   return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
3643 }
3644 #endif
3645 
3646 /*
3647 ** Object used to represent a single file opened and mmapped to provide
3648 ** shared memory.  When multiple threads all reference the same
3649 ** log-summary, each thread has its own winFile object, but they all
3650 ** point to a single instance of this object.  In other words, each
3651 ** log-summary is opened only once per process.
3652 **
3653 ** winShmMutexHeld() must be true when creating or destroying
3654 ** this object or while reading or writing the following fields:
3655 **
3656 **      nRef
3657 **      pNext
3658 **
3659 ** The following fields are read-only after the object is created:
3660 **
3661 **      fid
3662 **      zFilename
3663 **
3664 ** Either winShmNode.mutex must be held or winShmNode.nRef==0 and
3665 ** winShmMutexHeld() is true when reading or writing any other field
3666 ** in this structure.
3667 **
3668 */
3669 struct winShmNode {
3670   sqlite3_mutex *mutex;      /* Mutex to access this object */
3671   char *zFilename;           /* Name of the file */
3672   winFile hFile;             /* File handle from winOpen */
3673 
3674   int szRegion;              /* Size of shared-memory regions */
3675   int nRegion;               /* Size of array apRegion */
3676   struct ShmRegion {
3677     HANDLE hMap;             /* File handle from CreateFileMapping */
3678     void *pMap;
3679   } *aRegion;
3680   DWORD lastErrno;           /* The Windows errno from the last I/O error */
3681 
3682   int nRef;                  /* Number of winShm objects pointing to this */
3683   winShm *pFirst;            /* All winShm objects pointing to this */
3684   winShmNode *pNext;         /* Next in list of all winShmNode objects */
3685 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3686   u8 nextShmId;              /* Next available winShm.id value */
3687 #endif
3688 };
3689 
3690 /*
3691 ** A global array of all winShmNode objects.
3692 **
3693 ** The winShmMutexHeld() must be true while reading or writing this list.
3694 */
3695 static winShmNode *winShmNodeList = 0;
3696 
3697 /*
3698 ** Structure used internally by this VFS to record the state of an
3699 ** open shared memory connection.
3700 **
3701 ** The following fields are initialized when this object is created and
3702 ** are read-only thereafter:
3703 **
3704 **    winShm.pShmNode
3705 **    winShm.id
3706 **
3707 ** All other fields are read/write.  The winShm.pShmNode->mutex must be held
3708 ** while accessing any read/write fields.
3709 */
3710 struct winShm {
3711   winShmNode *pShmNode;      /* The underlying winShmNode object */
3712   winShm *pNext;             /* Next winShm with the same winShmNode */
3713   u8 hasMutex;               /* True if holding the winShmNode mutex */
3714   u16 sharedMask;            /* Mask of shared locks held */
3715   u16 exclMask;              /* Mask of exclusive locks held */
3716 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3717   u8 id;                     /* Id of this connection with its winShmNode */
3718 #endif
3719 };
3720 
3721 /*
3722 ** Constants used for locking
3723 */
3724 #define WIN_SHM_BASE   ((22+SQLITE_SHM_NLOCK)*4)        /* first lock byte */
3725 #define WIN_SHM_DMS    (WIN_SHM_BASE+SQLITE_SHM_NLOCK)  /* deadman switch */
3726 
3727 /*
3728 ** Apply advisory locks for all n bytes beginning at ofst.
3729 */
3730 #define WINSHM_UNLCK  1
3731 #define WINSHM_RDLCK  2
3732 #define WINSHM_WRLCK  3
3733 static int winShmSystemLock(
3734   winShmNode *pFile,    /* Apply locks to this open shared-memory segment */
3735   int lockType,         /* WINSHM_UNLCK, WINSHM_RDLCK, or WINSHM_WRLCK */
3736   int ofst,             /* Offset to first byte to be locked/unlocked */
3737   int nByte             /* Number of bytes to lock or unlock */
3738 ){
3739   int rc = 0;           /* Result code form Lock/UnlockFileEx() */
3740 
3741   /* Access to the winShmNode object is serialized by the caller */
3742   assert( sqlite3_mutex_held(pFile->mutex) || pFile->nRef==0 );
3743 
3744   OSTRACE(("SHM-LOCK file=%p, lock=%d, offset=%d, size=%d\n",
3745            pFile->hFile.h, lockType, ofst, nByte));
3746 
3747   /* Release/Acquire the system-level lock */
3748   if( lockType==WINSHM_UNLCK ){
3749     rc = winUnlockFile(&pFile->hFile.h, ofst, 0, nByte, 0);
3750   }else{
3751     /* Initialize the locking parameters */
3752     DWORD dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
3753     if( lockType == WINSHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
3754     rc = winLockFile(&pFile->hFile.h, dwFlags, ofst, 0, nByte, 0);
3755   }
3756 
3757   if( rc!= 0 ){
3758     rc = SQLITE_OK;
3759   }else{
3760     pFile->lastErrno =  osGetLastError();
3761     rc = SQLITE_BUSY;
3762   }
3763 
3764   OSTRACE(("SHM-LOCK file=%p, func=%s, errno=%lu, rc=%s\n",
3765            pFile->hFile.h, (lockType == WINSHM_UNLCK) ? "winUnlockFile" :
3766            "winLockFile", pFile->lastErrno, sqlite3ErrName(rc)));
3767 
3768   return rc;
3769 }
3770 
3771 /* Forward references to VFS methods */
3772 static int winOpen(sqlite3_vfs*,const char*,sqlite3_file*,int,int*);
3773 static int winDelete(sqlite3_vfs *,const char*,int);
3774 
3775 /*
3776 ** Purge the winShmNodeList list of all entries with winShmNode.nRef==0.
3777 **
3778 ** This is not a VFS shared-memory method; it is a utility function called
3779 ** by VFS shared-memory methods.
3780 */
3781 static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
3782   winShmNode **pp;
3783   winShmNode *p;
3784   assert( winShmMutexHeld() );
3785   OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
3786            osGetCurrentProcessId(), deleteFlag));
3787   pp = &winShmNodeList;
3788   while( (p = *pp)!=0 ){
3789     if( p->nRef==0 ){
3790       int i;
3791       if( p->mutex ){ sqlite3_mutex_free(p->mutex); }
3792       for(i=0; i<p->nRegion; i++){
3793         BOOL bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
3794         OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
3795                  osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
3796         UNUSED_VARIABLE_VALUE(bRc);
3797         bRc = osCloseHandle(p->aRegion[i].hMap);
3798         OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
3799                  osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
3800         UNUSED_VARIABLE_VALUE(bRc);
3801       }
3802       if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
3803         SimulateIOErrorBenign(1);
3804         winClose((sqlite3_file *)&p->hFile);
3805         SimulateIOErrorBenign(0);
3806       }
3807       if( deleteFlag ){
3808         SimulateIOErrorBenign(1);
3809         sqlite3BeginBenignMalloc();
3810         winDelete(pVfs, p->zFilename, 0);
3811         sqlite3EndBenignMalloc();
3812         SimulateIOErrorBenign(0);
3813       }
3814       *pp = p->pNext;
3815       sqlite3_free(p->aRegion);
3816       sqlite3_free(p);
3817     }else{
3818       pp = &p->pNext;
3819     }
3820   }
3821 }
3822 
3823 /*
3824 ** Open the shared-memory area associated with database file pDbFd.
3825 **
3826 ** When opening a new shared-memory file, if no other instances of that
3827 ** file are currently open, in this process or in other processes, then
3828 ** the file must be truncated to zero length or have its header cleared.
3829 */
3830 static int winOpenSharedMemory(winFile *pDbFd){
3831   struct winShm *p;                  /* The connection to be opened */
3832   struct winShmNode *pShmNode = 0;   /* The underlying mmapped file */
3833   int rc;                            /* Result code */
3834   struct winShmNode *pNew;           /* Newly allocated winShmNode */
3835   int nName;                         /* Size of zName in bytes */
3836 
3837   assert( pDbFd->pShm==0 );    /* Not previously opened */
3838 
3839   /* Allocate space for the new sqlite3_shm object.  Also speculatively
3840   ** allocate space for a new winShmNode and filename.
3841   */
3842   p = sqlite3MallocZero( sizeof(*p) );
3843   if( p==0 ) return SQLITE_IOERR_NOMEM_BKPT;
3844   nName = sqlite3Strlen30(pDbFd->zPath);
3845   pNew = sqlite3MallocZero( sizeof(*pShmNode) + nName + 17 );
3846   if( pNew==0 ){
3847     sqlite3_free(p);
3848     return SQLITE_IOERR_NOMEM_BKPT;
3849   }
3850   pNew->zFilename = (char*)&pNew[1];
3851   sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
3852   sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename);
3853 
3854   /* Look to see if there is an existing winShmNode that can be used.
3855   ** If no matching winShmNode currently exists, create a new one.
3856   */
3857   winShmEnterMutex();
3858   for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){
3859     /* TBD need to come up with better match here.  Perhaps
3860     ** use FILE_ID_BOTH_DIR_INFO Structure.
3861     */
3862     if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break;
3863   }
3864   if( pShmNode ){
3865     sqlite3_free(pNew);
3866   }else{
3867     pShmNode = pNew;
3868     pNew = 0;
3869     ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE;
3870     pShmNode->pNext = winShmNodeList;
3871     winShmNodeList = pShmNode;
3872 
3873     if( sqlite3GlobalConfig.bCoreMutex ){
3874       pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
3875       if( pShmNode->mutex==0 ){
3876         rc = SQLITE_IOERR_NOMEM_BKPT;
3877         goto shm_open_err;
3878       }
3879     }
3880 
3881     rc = winOpen(pDbFd->pVfs,
3882                  pShmNode->zFilename,             /* Name of the file (UTF-8) */
3883                  (sqlite3_file*)&pShmNode->hFile,  /* File handle here */
3884                  SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE,
3885                  0);
3886     if( SQLITE_OK!=rc ){
3887       goto shm_open_err;
3888     }
3889 
3890     /* Check to see if another process is holding the dead-man switch.
3891     ** If not, truncate the file to zero length.
3892     */
3893     if( winShmSystemLock(pShmNode, WINSHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){
3894       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0);
3895       if( rc!=SQLITE_OK ){
3896         rc = winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
3897                          "winOpenShm", pDbFd->zPath);
3898       }
3899     }
3900     if( rc==SQLITE_OK ){
3901       winShmSystemLock(pShmNode, WINSHM_UNLCK, WIN_SHM_DMS, 1);
3902       rc = winShmSystemLock(pShmNode, WINSHM_RDLCK, WIN_SHM_DMS, 1);
3903     }
3904     if( rc ) goto shm_open_err;
3905   }
3906 
3907   /* Make the new connection a child of the winShmNode */
3908   p->pShmNode = pShmNode;
3909 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3910   p->id = pShmNode->nextShmId++;
3911 #endif
3912   pShmNode->nRef++;
3913   pDbFd->pShm = p;
3914   winShmLeaveMutex();
3915 
3916   /* The reference count on pShmNode has already been incremented under
3917   ** the cover of the winShmEnterMutex() mutex and the pointer from the
3918   ** new (struct winShm) object to the pShmNode has been set. All that is
3919   ** left to do is to link the new object into the linked list starting
3920   ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex
3921   ** mutex.
3922   */
3923   sqlite3_mutex_enter(pShmNode->mutex);
3924   p->pNext = pShmNode->pFirst;
3925   pShmNode->pFirst = p;
3926   sqlite3_mutex_leave(pShmNode->mutex);
3927   return SQLITE_OK;
3928 
3929   /* Jump here on any error */
3930 shm_open_err:
3931   winShmSystemLock(pShmNode, WINSHM_UNLCK, WIN_SHM_DMS, 1);
3932   winShmPurge(pDbFd->pVfs, 0);      /* This call frees pShmNode if required */
3933   sqlite3_free(p);
3934   sqlite3_free(pNew);
3935   winShmLeaveMutex();
3936   return rc;
3937 }
3938 
3939 /*
3940 ** Close a connection to shared-memory.  Delete the underlying
3941 ** storage if deleteFlag is true.
3942 */
3943 static int winShmUnmap(
3944   sqlite3_file *fd,          /* Database holding shared memory */
3945   int deleteFlag             /* Delete after closing if true */
3946 ){
3947   winFile *pDbFd;       /* Database holding shared-memory */
3948   winShm *p;            /* The connection to be closed */
3949   winShmNode *pShmNode; /* The underlying shared-memory file */
3950   winShm **pp;          /* For looping over sibling connections */
3951 
3952   pDbFd = (winFile*)fd;
3953   p = pDbFd->pShm;
3954   if( p==0 ) return SQLITE_OK;
3955   pShmNode = p->pShmNode;
3956 
3957   /* Remove connection p from the set of connections associated
3958   ** with pShmNode */
3959   sqlite3_mutex_enter(pShmNode->mutex);
3960   for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
3961   *pp = p->pNext;
3962 
3963   /* Free the connection p */
3964   sqlite3_free(p);
3965   pDbFd->pShm = 0;
3966   sqlite3_mutex_leave(pShmNode->mutex);
3967 
3968   /* If pShmNode->nRef has reached 0, then close the underlying
3969   ** shared-memory file, too */
3970   winShmEnterMutex();
3971   assert( pShmNode->nRef>0 );
3972   pShmNode->nRef--;
3973   if( pShmNode->nRef==0 ){
3974     winShmPurge(pDbFd->pVfs, deleteFlag);
3975   }
3976   winShmLeaveMutex();
3977 
3978   return SQLITE_OK;
3979 }
3980 
3981 /*
3982 ** Change the lock state for a shared-memory segment.
3983 */
3984 static int winShmLock(
3985   sqlite3_file *fd,          /* Database file holding the shared memory */
3986   int ofst,                  /* First lock to acquire or release */
3987   int n,                     /* Number of locks to acquire or release */
3988   int flags                  /* What to do with the lock */
3989 ){
3990   winFile *pDbFd = (winFile*)fd;        /* Connection holding shared memory */
3991   winShm *p = pDbFd->pShm;              /* The shared memory being locked */
3992   winShm *pX;                           /* For looping over all siblings */
3993   winShmNode *pShmNode = p->pShmNode;
3994   int rc = SQLITE_OK;                   /* Result code */
3995   u16 mask;                             /* Mask of locks to take or release */
3996 
3997   assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
3998   assert( n>=1 );
3999   assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
4000        || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
4001        || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
4002        || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
4003   assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
4004 
4005   mask = (u16)((1U<<(ofst+n)) - (1U<<ofst));
4006   assert( n>1 || mask==(1<<ofst) );
4007   sqlite3_mutex_enter(pShmNode->mutex);
4008   if( flags & SQLITE_SHM_UNLOCK ){
4009     u16 allMask = 0; /* Mask of locks held by siblings */
4010 
4011     /* See if any siblings hold this same lock */
4012     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
4013       if( pX==p ) continue;
4014       assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
4015       allMask |= pX->sharedMask;
4016     }
4017 
4018     /* Unlock the system-level locks */
4019     if( (mask & allMask)==0 ){
4020       rc = winShmSystemLock(pShmNode, WINSHM_UNLCK, ofst+WIN_SHM_BASE, n);
4021     }else{
4022       rc = SQLITE_OK;
4023     }
4024 
4025     /* Undo the local locks */
4026     if( rc==SQLITE_OK ){
4027       p->exclMask &= ~mask;
4028       p->sharedMask &= ~mask;
4029     }
4030   }else if( flags & SQLITE_SHM_SHARED ){
4031     u16 allShared = 0;  /* Union of locks held by connections other than "p" */
4032 
4033     /* Find out which shared locks are already held by sibling connections.
4034     ** If any sibling already holds an exclusive lock, go ahead and return
4035     ** SQLITE_BUSY.
4036     */
4037     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
4038       if( (pX->exclMask & mask)!=0 ){
4039         rc = SQLITE_BUSY;
4040         break;
4041       }
4042       allShared |= pX->sharedMask;
4043     }
4044 
4045     /* Get shared locks at the system level, if necessary */
4046     if( rc==SQLITE_OK ){
4047       if( (allShared & mask)==0 ){
4048         rc = winShmSystemLock(pShmNode, WINSHM_RDLCK, ofst+WIN_SHM_BASE, n);
4049       }else{
4050         rc = SQLITE_OK;
4051       }
4052     }
4053 
4054     /* Get the local shared locks */
4055     if( rc==SQLITE_OK ){
4056       p->sharedMask |= mask;
4057     }
4058   }else{
4059     /* Make sure no sibling connections hold locks that will block this
4060     ** lock.  If any do, return SQLITE_BUSY right away.
4061     */
4062     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
4063       if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
4064         rc = SQLITE_BUSY;
4065         break;
4066       }
4067     }
4068 
4069     /* Get the exclusive locks at the system level.  Then if successful
4070     ** also mark the local connection as being locked.
4071     */
4072     if( rc==SQLITE_OK ){
4073       rc = winShmSystemLock(pShmNode, WINSHM_WRLCK, ofst+WIN_SHM_BASE, n);
4074       if( rc==SQLITE_OK ){
4075         assert( (p->sharedMask & mask)==0 );
4076         p->exclMask |= mask;
4077       }
4078     }
4079   }
4080   sqlite3_mutex_leave(pShmNode->mutex);
4081   OSTRACE(("SHM-LOCK pid=%lu, id=%d, sharedMask=%03x, exclMask=%03x, rc=%s\n",
4082            osGetCurrentProcessId(), p->id, p->sharedMask, p->exclMask,
4083            sqlite3ErrName(rc)));
4084   return rc;
4085 }
4086 
4087 /*
4088 ** Implement a memory barrier or memory fence on shared memory.
4089 **
4090 ** All loads and stores begun before the barrier must complete before
4091 ** any load or store begun after the barrier.
4092 */
4093 static void winShmBarrier(
4094   sqlite3_file *fd          /* Database holding the shared memory */
4095 ){
4096   UNUSED_PARAMETER(fd);
4097   sqlite3MemoryBarrier();   /* compiler-defined memory barrier */
4098   winShmEnterMutex();       /* Also mutex, for redundancy */
4099   winShmLeaveMutex();
4100 }
4101 
4102 /*
4103 ** This function is called to obtain a pointer to region iRegion of the
4104 ** shared-memory associated with the database file fd. Shared-memory regions
4105 ** are numbered starting from zero. Each shared-memory region is szRegion
4106 ** bytes in size.
4107 **
4108 ** If an error occurs, an error code is returned and *pp is set to NULL.
4109 **
4110 ** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
4111 ** region has not been allocated (by any client, including one running in a
4112 ** separate process), then *pp is set to NULL and SQLITE_OK returned. If
4113 ** isWrite is non-zero and the requested shared-memory region has not yet
4114 ** been allocated, it is allocated by this function.
4115 **
4116 ** If the shared-memory region has already been allocated or is allocated by
4117 ** this call as described above, then it is mapped into this processes
4118 ** address space (if it is not already), *pp is set to point to the mapped
4119 ** memory and SQLITE_OK returned.
4120 */
4121 static int winShmMap(
4122   sqlite3_file *fd,               /* Handle open on database file */
4123   int iRegion,                    /* Region to retrieve */
4124   int szRegion,                   /* Size of regions */
4125   int isWrite,                    /* True to extend file if necessary */
4126   void volatile **pp              /* OUT: Mapped memory */
4127 ){
4128   winFile *pDbFd = (winFile*)fd;
4129   winShm *pShm = pDbFd->pShm;
4130   winShmNode *pShmNode;
4131   int rc = SQLITE_OK;
4132 
4133   if( !pShm ){
4134     rc = winOpenSharedMemory(pDbFd);
4135     if( rc!=SQLITE_OK ) return rc;
4136     pShm = pDbFd->pShm;
4137   }
4138   pShmNode = pShm->pShmNode;
4139 
4140   sqlite3_mutex_enter(pShmNode->mutex);
4141   assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
4142 
4143   if( pShmNode->nRegion<=iRegion ){
4144     struct ShmRegion *apNew;           /* New aRegion[] array */
4145     int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
4146     sqlite3_int64 sz;                  /* Current size of wal-index file */
4147 
4148     pShmNode->szRegion = szRegion;
4149 
4150     /* The requested region is not mapped into this processes address space.
4151     ** Check to see if it has been allocated (i.e. if the wal-index file is
4152     ** large enough to contain the requested region).
4153     */
4154     rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
4155     if( rc!=SQLITE_OK ){
4156       rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
4157                        "winShmMap1", pDbFd->zPath);
4158       goto shmpage_out;
4159     }
4160 
4161     if( sz<nByte ){
4162       /* The requested memory region does not exist. If isWrite is set to
4163       ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
4164       **
4165       ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
4166       ** the requested memory region.
4167       */
4168       if( !isWrite ) goto shmpage_out;
4169       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
4170       if( rc!=SQLITE_OK ){
4171         rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
4172                          "winShmMap2", pDbFd->zPath);
4173         goto shmpage_out;
4174       }
4175     }
4176 
4177     /* Map the requested memory region into this processes address space. */
4178     apNew = (struct ShmRegion *)sqlite3_realloc64(
4179         pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
4180     );
4181     if( !apNew ){
4182       rc = SQLITE_IOERR_NOMEM_BKPT;
4183       goto shmpage_out;
4184     }
4185     pShmNode->aRegion = apNew;
4186 
4187     while( pShmNode->nRegion<=iRegion ){
4188       HANDLE hMap = NULL;         /* file-mapping handle */
4189       void *pMap = 0;             /* Mapped memory region */
4190 
4191 #if SQLITE_OS_WINRT
4192       hMap = osCreateFileMappingFromApp(pShmNode->hFile.h,
4193           NULL, PAGE_READWRITE, nByte, NULL
4194       );
4195 #elif defined(SQLITE_WIN32_HAS_WIDE)
4196       hMap = osCreateFileMappingW(pShmNode->hFile.h,
4197           NULL, PAGE_READWRITE, 0, nByte, NULL
4198       );
4199 #elif defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_CREATEFILEMAPPINGA
4200       hMap = osCreateFileMappingA(pShmNode->hFile.h,
4201           NULL, PAGE_READWRITE, 0, nByte, NULL
4202       );
4203 #endif
4204       OSTRACE(("SHM-MAP-CREATE pid=%lu, region=%d, size=%d, rc=%s\n",
4205                osGetCurrentProcessId(), pShmNode->nRegion, nByte,
4206                hMap ? "ok" : "failed"));
4207       if( hMap ){
4208         int iOffset = pShmNode->nRegion*szRegion;
4209         int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
4210 #if SQLITE_OS_WINRT
4211         pMap = osMapViewOfFileFromApp(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
4212             iOffset - iOffsetShift, szRegion + iOffsetShift
4213         );
4214 #else
4215         pMap = osMapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
4216             0, iOffset - iOffsetShift, szRegion + iOffsetShift
4217         );
4218 #endif
4219         OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
4220                  osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
4221                  szRegion, pMap ? "ok" : "failed"));
4222       }
4223       if( !pMap ){
4224         pShmNode->lastErrno = osGetLastError();
4225         rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
4226                          "winShmMap3", pDbFd->zPath);
4227         if( hMap ) osCloseHandle(hMap);
4228         goto shmpage_out;
4229       }
4230 
4231       pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
4232       pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
4233       pShmNode->nRegion++;
4234     }
4235   }
4236 
4237 shmpage_out:
4238   if( pShmNode->nRegion>iRegion ){
4239     int iOffset = iRegion*szRegion;
4240     int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
4241     char *p = (char *)pShmNode->aRegion[iRegion].pMap;
4242     *pp = (void *)&p[iOffsetShift];
4243   }else{
4244     *pp = 0;
4245   }
4246   sqlite3_mutex_leave(pShmNode->mutex);
4247   return rc;
4248 }
4249 
4250 #else
4251 # define winShmMap     0
4252 # define winShmLock    0
4253 # define winShmBarrier 0
4254 # define winShmUnmap   0
4255 #endif /* #ifndef SQLITE_OMIT_WAL */
4256 
4257 /*
4258 ** Cleans up the mapped region of the specified file, if any.
4259 */
4260 #if SQLITE_MAX_MMAP_SIZE>0
4261 static int winUnmapfile(winFile *pFile){
4262   assert( pFile!=0 );
4263   OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, pMapRegion=%p, "
4264            "mmapSize=%lld, mmapSizeActual=%lld, mmapSizeMax=%lld\n",
4265            osGetCurrentProcessId(), pFile, pFile->hMap, pFile->pMapRegion,
4266            pFile->mmapSize, pFile->mmapSizeActual, pFile->mmapSizeMax));
4267   if( pFile->pMapRegion ){
4268     if( !osUnmapViewOfFile(pFile->pMapRegion) ){
4269       pFile->lastErrno = osGetLastError();
4270       OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
4271                "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
4272                pFile->pMapRegion));
4273       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
4274                          "winUnmapfile1", pFile->zPath);
4275     }
4276     pFile->pMapRegion = 0;
4277     pFile->mmapSize = 0;
4278     pFile->mmapSizeActual = 0;
4279   }
4280   if( pFile->hMap!=NULL ){
4281     if( !osCloseHandle(pFile->hMap) ){
4282       pFile->lastErrno = osGetLastError();
4283       OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
4284                osGetCurrentProcessId(), pFile, pFile->hMap));
4285       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
4286                          "winUnmapfile2", pFile->zPath);
4287     }
4288     pFile->hMap = NULL;
4289   }
4290   OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
4291            osGetCurrentProcessId(), pFile));
4292   return SQLITE_OK;
4293 }
4294 
4295 /*
4296 ** Memory map or remap the file opened by file-descriptor pFd (if the file
4297 ** is already mapped, the existing mapping is replaced by the new). Or, if
4298 ** there already exists a mapping for this file, and there are still
4299 ** outstanding xFetch() references to it, this function is a no-op.
4300 **
4301 ** If parameter nByte is non-negative, then it is the requested size of
4302 ** the mapping to create. Otherwise, if nByte is less than zero, then the
4303 ** requested size is the size of the file on disk. The actual size of the
4304 ** created mapping is either the requested size or the value configured
4305 ** using SQLITE_FCNTL_MMAP_SIZE, whichever is smaller.
4306 **
4307 ** SQLITE_OK is returned if no error occurs (even if the mapping is not
4308 ** recreated as a result of outstanding references) or an SQLite error
4309 ** code otherwise.
4310 */
4311 static int winMapfile(winFile *pFd, sqlite3_int64 nByte){
4312   sqlite3_int64 nMap = nByte;
4313   int rc;
4314 
4315   assert( nMap>=0 || pFd->nFetchOut==0 );
4316   OSTRACE(("MAP-FILE pid=%lu, pFile=%p, size=%lld\n",
4317            osGetCurrentProcessId(), pFd, nByte));
4318 
4319   if( pFd->nFetchOut>0 ) return SQLITE_OK;
4320 
4321   if( nMap<0 ){
4322     rc = winFileSize((sqlite3_file*)pFd, &nMap);
4323     if( rc ){
4324       OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_IOERR_FSTAT\n",
4325                osGetCurrentProcessId(), pFd));
4326       return SQLITE_IOERR_FSTAT;
4327     }
4328   }
4329   if( nMap>pFd->mmapSizeMax ){
4330     nMap = pFd->mmapSizeMax;
4331   }
4332   nMap &= ~(sqlite3_int64)(winSysInfo.dwPageSize - 1);
4333 
4334   if( nMap==0 && pFd->mmapSize>0 ){
4335     winUnmapfile(pFd);
4336   }
4337   if( nMap!=pFd->mmapSize ){
4338     void *pNew = 0;
4339     DWORD protect = PAGE_READONLY;
4340     DWORD flags = FILE_MAP_READ;
4341 
4342     winUnmapfile(pFd);
4343 #ifdef SQLITE_MMAP_READWRITE
4344     if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
4345       protect = PAGE_READWRITE;
4346       flags |= FILE_MAP_WRITE;
4347     }
4348 #endif
4349 #if SQLITE_OS_WINRT
4350     pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
4351 #elif defined(SQLITE_WIN32_HAS_WIDE)
4352     pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
4353                                 (DWORD)((nMap>>32) & 0xffffffff),
4354                                 (DWORD)(nMap & 0xffffffff), NULL);
4355 #elif defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_CREATEFILEMAPPINGA
4356     pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
4357                                 (DWORD)((nMap>>32) & 0xffffffff),
4358                                 (DWORD)(nMap & 0xffffffff), NULL);
4359 #endif
4360     if( pFd->hMap==NULL ){
4361       pFd->lastErrno = osGetLastError();
4362       rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
4363                        "winMapfile1", pFd->zPath);
4364       /* Log the error, but continue normal operation using xRead/xWrite */
4365       OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=%s\n",
4366                osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
4367       return SQLITE_OK;
4368     }
4369     assert( (nMap % winSysInfo.dwPageSize)==0 );
4370     assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
4371 #if SQLITE_OS_WINRT
4372     pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
4373 #else
4374     pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
4375 #endif
4376     if( pNew==NULL ){
4377       osCloseHandle(pFd->hMap);
4378       pFd->hMap = NULL;
4379       pFd->lastErrno = osGetLastError();
4380       rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
4381                        "winMapfile2", pFd->zPath);
4382       /* Log the error, but continue normal operation using xRead/xWrite */
4383       OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=%s\n",
4384                osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
4385       return SQLITE_OK;
4386     }
4387     pFd->pMapRegion = pNew;
4388     pFd->mmapSize = nMap;
4389     pFd->mmapSizeActual = nMap;
4390   }
4391 
4392   OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
4393            osGetCurrentProcessId(), pFd));
4394   return SQLITE_OK;
4395 }
4396 #endif /* SQLITE_MAX_MMAP_SIZE>0 */
4397 
4398 /*
4399 ** If possible, return a pointer to a mapping of file fd starting at offset
4400 ** iOff. The mapping must be valid for at least nAmt bytes.
4401 **
4402 ** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
4403 ** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
4404 ** Finally, if an error does occur, return an SQLite error code. The final
4405 ** value of *pp is undefined in this case.
4406 **
4407 ** If this function does return a pointer, the caller must eventually
4408 ** release the reference by calling winUnfetch().
4409 */
4410 static int winFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
4411 #if SQLITE_MAX_MMAP_SIZE>0
4412   winFile *pFd = (winFile*)fd;   /* The underlying database file */
4413 #endif
4414   *pp = 0;
4415 
4416   OSTRACE(("FETCH pid=%lu, pFile=%p, offset=%lld, amount=%d, pp=%p\n",
4417            osGetCurrentProcessId(), fd, iOff, nAmt, pp));
4418 
4419 #if SQLITE_MAX_MMAP_SIZE>0
4420   if( pFd->mmapSizeMax>0 ){
4421     if( pFd->pMapRegion==0 ){
4422       int rc = winMapfile(pFd, -1);
4423       if( rc!=SQLITE_OK ){
4424         OSTRACE(("FETCH pid=%lu, pFile=%p, rc=%s\n",
4425                  osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
4426         return rc;
4427       }
4428     }
4429     if( pFd->mmapSize >= iOff+nAmt ){
4430       *pp = &((u8 *)pFd->pMapRegion)[iOff];
4431       pFd->nFetchOut++;
4432     }
4433   }
4434 #endif
4435 
4436   OSTRACE(("FETCH pid=%lu, pFile=%p, pp=%p, *pp=%p, rc=SQLITE_OK\n",
4437            osGetCurrentProcessId(), fd, pp, *pp));
4438   return SQLITE_OK;
4439 }
4440 
4441 /*
4442 ** If the third argument is non-NULL, then this function releases a
4443 ** reference obtained by an earlier call to winFetch(). The second
4444 ** argument passed to this function must be the same as the corresponding
4445 ** argument that was passed to the winFetch() invocation.
4446 **
4447 ** Or, if the third argument is NULL, then this function is being called
4448 ** to inform the VFS layer that, according to POSIX, any existing mapping
4449 ** may now be invalid and should be unmapped.
4450 */
4451 static int winUnfetch(sqlite3_file *fd, i64 iOff, void *p){
4452 #if SQLITE_MAX_MMAP_SIZE>0
4453   winFile *pFd = (winFile*)fd;   /* The underlying database file */
4454 
4455   /* If p==0 (unmap the entire file) then there must be no outstanding
4456   ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
4457   ** then there must be at least one outstanding.  */
4458   assert( (p==0)==(pFd->nFetchOut==0) );
4459 
4460   /* If p!=0, it must match the iOff value. */
4461   assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
4462 
4463   OSTRACE(("UNFETCH pid=%lu, pFile=%p, offset=%lld, p=%p\n",
4464            osGetCurrentProcessId(), pFd, iOff, p));
4465 
4466   if( p ){
4467     pFd->nFetchOut--;
4468   }else{
4469     /* FIXME:  If Windows truly always prevents truncating or deleting a
4470     ** file while a mapping is held, then the following winUnmapfile() call
4471     ** is unnecessary can be omitted - potentially improving
4472     ** performance.  */
4473     winUnmapfile(pFd);
4474   }
4475 
4476   assert( pFd->nFetchOut>=0 );
4477 #endif
4478 
4479   OSTRACE(("UNFETCH pid=%lu, pFile=%p, rc=SQLITE_OK\n",
4480            osGetCurrentProcessId(), fd));
4481   return SQLITE_OK;
4482 }
4483 
4484 /*
4485 ** Here ends the implementation of all sqlite3_file methods.
4486 **
4487 ********************** End sqlite3_file Methods *******************************
4488 ******************************************************************************/
4489 
4490 /*
4491 ** This vector defines all the methods that can operate on an
4492 ** sqlite3_file for win32.
4493 */
4494 static const sqlite3_io_methods winIoMethod = {
4495   3,                              /* iVersion */
4496   winClose,                       /* xClose */
4497   winRead,                        /* xRead */
4498   winWrite,                       /* xWrite */
4499   winTruncate,                    /* xTruncate */
4500   winSync,                        /* xSync */
4501   winFileSize,                    /* xFileSize */
4502   winLock,                        /* xLock */
4503   winUnlock,                      /* xUnlock */
4504   winCheckReservedLock,           /* xCheckReservedLock */
4505   winFileControl,                 /* xFileControl */
4506   winSectorSize,                  /* xSectorSize */
4507   winDeviceCharacteristics,       /* xDeviceCharacteristics */
4508   winShmMap,                      /* xShmMap */
4509   winShmLock,                     /* xShmLock */
4510   winShmBarrier,                  /* xShmBarrier */
4511   winShmUnmap,                    /* xShmUnmap */
4512   winFetch,                       /* xFetch */
4513   winUnfetch                      /* xUnfetch */
4514 };
4515 
4516 /*
4517 ** This vector defines all the methods that can operate on an
4518 ** sqlite3_file for win32 without performing any locking.
4519 */
4520 static const sqlite3_io_methods winIoNolockMethod = {
4521   3,                              /* iVersion */
4522   winClose,                       /* xClose */
4523   winRead,                        /* xRead */
4524   winWrite,                       /* xWrite */
4525   winTruncate,                    /* xTruncate */
4526   winSync,                        /* xSync */
4527   winFileSize,                    /* xFileSize */
4528   winNolockLock,                  /* xLock */
4529   winNolockUnlock,                /* xUnlock */
4530   winNolockCheckReservedLock,     /* xCheckReservedLock */
4531   winFileControl,                 /* xFileControl */
4532   winSectorSize,                  /* xSectorSize */
4533   winDeviceCharacteristics,       /* xDeviceCharacteristics */
4534   winShmMap,                      /* xShmMap */
4535   winShmLock,                     /* xShmLock */
4536   winShmBarrier,                  /* xShmBarrier */
4537   winShmUnmap,                    /* xShmUnmap */
4538   winFetch,                       /* xFetch */
4539   winUnfetch                      /* xUnfetch */
4540 };
4541 
4542 static winVfsAppData winAppData = {
4543   &winIoMethod,       /* pMethod */
4544   0,                  /* pAppData */
4545   0                   /* bNoLock */
4546 };
4547 
4548 static winVfsAppData winNolockAppData = {
4549   &winIoNolockMethod, /* pMethod */
4550   0,                  /* pAppData */
4551   1                   /* bNoLock */
4552 };
4553 
4554 /****************************************************************************
4555 **************************** sqlite3_vfs methods ****************************
4556 **
4557 ** This division contains the implementation of methods on the
4558 ** sqlite3_vfs object.
4559 */
4560 
4561 #if defined(__CYGWIN__)
4562 /*
4563 ** Convert a filename from whatever the underlying operating system
4564 ** supports for filenames into UTF-8.  Space to hold the result is
4565 ** obtained from malloc and must be freed by the calling function.
4566 */
4567 static char *winConvertToUtf8Filename(const void *zFilename){
4568   char *zConverted = 0;
4569   if( osIsNT() ){
4570     zConverted = winUnicodeToUtf8(zFilename);
4571   }
4572 #ifdef SQLITE_WIN32_HAS_ANSI
4573   else{
4574     zConverted = winMbcsToUtf8(zFilename, osAreFileApisANSI());
4575   }
4576 #endif
4577   /* caller will handle out of memory */
4578   return zConverted;
4579 }
4580 #endif
4581 
4582 /*
4583 ** Convert a UTF-8 filename into whatever form the underlying
4584 ** operating system wants filenames in.  Space to hold the result
4585 ** is obtained from malloc and must be freed by the calling
4586 ** function.
4587 */
4588 static void *winConvertFromUtf8Filename(const char *zFilename){
4589   void *zConverted = 0;
4590   if( osIsNT() ){
4591     zConverted = winUtf8ToUnicode(zFilename);
4592   }
4593 #ifdef SQLITE_WIN32_HAS_ANSI
4594   else{
4595     zConverted = winUtf8ToMbcs(zFilename, osAreFileApisANSI());
4596   }
4597 #endif
4598   /* caller will handle out of memory */
4599   return zConverted;
4600 }
4601 
4602 /*
4603 ** This function returns non-zero if the specified UTF-8 string buffer
4604 ** ends with a directory separator character or one was successfully
4605 ** added to it.
4606 */
4607 static int winMakeEndInDirSep(int nBuf, char *zBuf){
4608   if( zBuf ){
4609     int nLen = sqlite3Strlen30(zBuf);
4610     if( nLen>0 ){
4611       if( winIsDirSep(zBuf[nLen-1]) ){
4612         return 1;
4613       }else if( nLen+1<nBuf ){
4614         zBuf[nLen] = winGetDirSep();
4615         zBuf[nLen+1] = '\0';
4616         return 1;
4617       }
4618     }
4619   }
4620   return 0;
4621 }
4622 
4623 /*
4624 ** Create a temporary file name and store the resulting pointer into pzBuf.
4625 ** The pointer returned in pzBuf must be freed via sqlite3_free().
4626 */
4627 static int winGetTempname(sqlite3_vfs *pVfs, char **pzBuf){
4628   static char zChars[] =
4629     "abcdefghijklmnopqrstuvwxyz"
4630     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
4631     "0123456789";
4632   size_t i, j;
4633   int nPre = sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX);
4634   int nMax, nBuf, nDir, nLen;
4635   char *zBuf;
4636 
4637   /* It's odd to simulate an io-error here, but really this is just
4638   ** using the io-error infrastructure to test that SQLite handles this
4639   ** function failing.
4640   */
4641   SimulateIOError( return SQLITE_IOERR );
4642 
4643   /* Allocate a temporary buffer to store the fully qualified file
4644   ** name for the temporary file.  If this fails, we cannot continue.
4645   */
4646   nMax = pVfs->mxPathname; nBuf = nMax + 2;
4647   zBuf = sqlite3MallocZero( nBuf );
4648   if( !zBuf ){
4649     OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4650     return SQLITE_IOERR_NOMEM_BKPT;
4651   }
4652 
4653   /* Figure out the effective temporary directory.  First, check if one
4654   ** has been explicitly set by the application; otherwise, use the one
4655   ** configured by the operating system.
4656   */
4657   nDir = nMax - (nPre + 15);
4658   assert( nDir>0 );
4659   if( sqlite3_temp_directory ){
4660     int nDirLen = sqlite3Strlen30(sqlite3_temp_directory);
4661     if( nDirLen>0 ){
4662       if( !winIsDirSep(sqlite3_temp_directory[nDirLen-1]) ){
4663         nDirLen++;
4664       }
4665       if( nDirLen>nDir ){
4666         sqlite3_free(zBuf);
4667         OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4668         return winLogError(SQLITE_ERROR, 0, "winGetTempname1", 0);
4669       }
4670       sqlite3_snprintf(nMax, zBuf, "%s", sqlite3_temp_directory);
4671     }
4672   }
4673 #if defined(__CYGWIN__)
4674   else{
4675     static const char *azDirs[] = {
4676        0, /* getenv("SQLITE_TMPDIR") */
4677        0, /* getenv("TMPDIR") */
4678        0, /* getenv("TMP") */
4679        0, /* getenv("TEMP") */
4680        0, /* getenv("USERPROFILE") */
4681        "/var/tmp",
4682        "/usr/tmp",
4683        "/tmp",
4684        ".",
4685        0        /* List terminator */
4686     };
4687     unsigned int i;
4688     const char *zDir = 0;
4689 
4690     if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
4691     if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
4692     if( !azDirs[2] ) azDirs[2] = getenv("TMP");
4693     if( !azDirs[3] ) azDirs[3] = getenv("TEMP");
4694     if( !azDirs[4] ) azDirs[4] = getenv("USERPROFILE");
4695     for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
4696       void *zConverted;
4697       if( zDir==0 ) continue;
4698       /* If the path starts with a drive letter followed by the colon
4699       ** character, assume it is already a native Win32 path; otherwise,
4700       ** it must be converted to a native Win32 path via the Cygwin API
4701       ** prior to using it.
4702       */
4703       if( winIsDriveLetterAndColon(zDir) ){
4704         zConverted = winConvertFromUtf8Filename(zDir);
4705         if( !zConverted ){
4706           sqlite3_free(zBuf);
4707           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4708           return SQLITE_IOERR_NOMEM_BKPT;
4709         }
4710         if( winIsDir(zConverted) ){
4711           sqlite3_snprintf(nMax, zBuf, "%s", zDir);
4712           sqlite3_free(zConverted);
4713           break;
4714         }
4715         sqlite3_free(zConverted);
4716       }else{
4717         zConverted = sqlite3MallocZero( nMax+1 );
4718         if( !zConverted ){
4719           sqlite3_free(zBuf);
4720           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4721           return SQLITE_IOERR_NOMEM_BKPT;
4722         }
4723         if( cygwin_conv_path(
4724                 osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A, zDir,
4725                 zConverted, nMax+1)<0 ){
4726           sqlite3_free(zConverted);
4727           sqlite3_free(zBuf);
4728           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_CONVPATH\n"));
4729           return winLogError(SQLITE_IOERR_CONVPATH, (DWORD)errno,
4730                              "winGetTempname2", zDir);
4731         }
4732         if( winIsDir(zConverted) ){
4733           /* At this point, we know the candidate directory exists and should
4734           ** be used.  However, we may need to convert the string containing
4735           ** its name into UTF-8 (i.e. if it is UTF-16 right now).
4736           */
4737           char *zUtf8 = winConvertToUtf8Filename(zConverted);
4738           if( !zUtf8 ){
4739             sqlite3_free(zConverted);
4740             sqlite3_free(zBuf);
4741             OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4742             return SQLITE_IOERR_NOMEM_BKPT;
4743           }
4744           sqlite3_snprintf(nMax, zBuf, "%s", zUtf8);
4745           sqlite3_free(zUtf8);
4746           sqlite3_free(zConverted);
4747           break;
4748         }
4749         sqlite3_free(zConverted);
4750       }
4751     }
4752   }
4753 #elif !SQLITE_OS_WINRT && !defined(__CYGWIN__)
4754   else if( osIsNT() ){
4755     char *zMulti;
4756     LPWSTR zWidePath = sqlite3MallocZero( nMax*sizeof(WCHAR) );
4757     if( !zWidePath ){
4758       sqlite3_free(zBuf);
4759       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4760       return SQLITE_IOERR_NOMEM_BKPT;
4761     }
4762     if( osGetTempPathW(nMax, zWidePath)==0 ){
4763       sqlite3_free(zWidePath);
4764       sqlite3_free(zBuf);
4765       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
4766       return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
4767                          "winGetTempname2", 0);
4768     }
4769     zMulti = winUnicodeToUtf8(zWidePath);
4770     if( zMulti ){
4771       sqlite3_snprintf(nMax, zBuf, "%s", zMulti);
4772       sqlite3_free(zMulti);
4773       sqlite3_free(zWidePath);
4774     }else{
4775       sqlite3_free(zWidePath);
4776       sqlite3_free(zBuf);
4777       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4778       return SQLITE_IOERR_NOMEM_BKPT;
4779     }
4780   }
4781 #ifdef SQLITE_WIN32_HAS_ANSI
4782   else{
4783     char *zUtf8;
4784     char *zMbcsPath = sqlite3MallocZero( nMax );
4785     if( !zMbcsPath ){
4786       sqlite3_free(zBuf);
4787       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4788       return SQLITE_IOERR_NOMEM_BKPT;
4789     }
4790     if( osGetTempPathA(nMax, zMbcsPath)==0 ){
4791       sqlite3_free(zBuf);
4792       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
4793       return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
4794                          "winGetTempname3", 0);
4795     }
4796     zUtf8 = winMbcsToUtf8(zMbcsPath, osAreFileApisANSI());
4797     if( zUtf8 ){
4798       sqlite3_snprintf(nMax, zBuf, "%s", zUtf8);
4799       sqlite3_free(zUtf8);
4800     }else{
4801       sqlite3_free(zBuf);
4802       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4803       return SQLITE_IOERR_NOMEM_BKPT;
4804     }
4805   }
4806 #endif /* SQLITE_WIN32_HAS_ANSI */
4807 #endif /* !SQLITE_OS_WINRT */
4808 
4809   /*
4810   ** Check to make sure the temporary directory ends with an appropriate
4811   ** separator.  If it does not and there is not enough space left to add
4812   ** one, fail.
4813   */
4814   if( !winMakeEndInDirSep(nDir+1, zBuf) ){
4815     sqlite3_free(zBuf);
4816     OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4817     return winLogError(SQLITE_ERROR, 0, "winGetTempname4", 0);
4818   }
4819 
4820   /*
4821   ** Check that the output buffer is large enough for the temporary file
4822   ** name in the following format:
4823   **
4824   **   "<temporary_directory>/etilqs_XXXXXXXXXXXXXXX\0\0"
4825   **
4826   ** If not, return SQLITE_ERROR.  The number 17 is used here in order to
4827   ** account for the space used by the 15 character random suffix and the
4828   ** two trailing NUL characters.  The final directory separator character
4829   ** has already added if it was not already present.
4830   */
4831   nLen = sqlite3Strlen30(zBuf);
4832   if( (nLen + nPre + 17) > nBuf ){
4833     sqlite3_free(zBuf);
4834     OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4835     return winLogError(SQLITE_ERROR, 0, "winGetTempname5", 0);
4836   }
4837 
4838   sqlite3_snprintf(nBuf-16-nLen, zBuf+nLen, SQLITE_TEMP_FILE_PREFIX);
4839 
4840   j = sqlite3Strlen30(zBuf);
4841   sqlite3_randomness(15, &zBuf[j]);
4842   for(i=0; i<15; i++, j++){
4843     zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
4844   }
4845   zBuf[j] = 0;
4846   zBuf[j+1] = 0;
4847   *pzBuf = zBuf;
4848 
4849   OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
4850   return SQLITE_OK;
4851 }
4852 
4853 /*
4854 ** Return TRUE if the named file is really a directory.  Return false if
4855 ** it is something other than a directory, or if there is any kind of memory
4856 ** allocation failure.
4857 */
4858 static int winIsDir(const void *zConverted){
4859   DWORD attr;
4860   int rc = 0;
4861   DWORD lastErrno;
4862 
4863   if( osIsNT() ){
4864     int cnt = 0;
4865     WIN32_FILE_ATTRIBUTE_DATA sAttrData;
4866     memset(&sAttrData, 0, sizeof(sAttrData));
4867     while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
4868                              GetFileExInfoStandard,
4869                              &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
4870     if( !rc ){
4871       return 0; /* Invalid name? */
4872     }
4873     attr = sAttrData.dwFileAttributes;
4874 #if SQLITE_OS_WINCE==0
4875   }else{
4876     attr = osGetFileAttributesA((char*)zConverted);
4877 #endif
4878   }
4879   return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
4880 }
4881 
4882 /*
4883 ** Open a file.
4884 */
4885 static int winOpen(
4886   sqlite3_vfs *pVfs,        /* Used to get maximum path length and AppData */
4887   const char *zName,        /* Name of the file (UTF-8) */
4888   sqlite3_file *id,         /* Write the SQLite file handle here */
4889   int flags,                /* Open mode flags */
4890   int *pOutFlags            /* Status return flags */
4891 ){
4892   HANDLE h;
4893   DWORD lastErrno = 0;
4894   DWORD dwDesiredAccess;
4895   DWORD dwShareMode;
4896   DWORD dwCreationDisposition;
4897   DWORD dwFlagsAndAttributes = 0;
4898 #if SQLITE_OS_WINCE
4899   int isTemp = 0;
4900 #endif
4901   winVfsAppData *pAppData;
4902   winFile *pFile = (winFile*)id;
4903   void *zConverted;              /* Filename in OS encoding */
4904   const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
4905   int cnt = 0;
4906 
4907   /* If argument zPath is a NULL pointer, this function is required to open
4908   ** a temporary file. Use this buffer to store the file name in.
4909   */
4910   char *zTmpname = 0; /* For temporary filename, if necessary. */
4911 
4912   int rc = SQLITE_OK;            /* Function Return Code */
4913 #if !defined(NDEBUG) || SQLITE_OS_WINCE
4914   int eType = flags&0xFFFFFF00;  /* Type of file to open */
4915 #endif
4916 
4917   int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
4918   int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
4919   int isCreate     = (flags & SQLITE_OPEN_CREATE);
4920   int isReadonly   = (flags & SQLITE_OPEN_READONLY);
4921   int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
4922 
4923 #ifndef NDEBUG
4924   int isOpenJournal = (isCreate && (
4925         eType==SQLITE_OPEN_MASTER_JOURNAL
4926      || eType==SQLITE_OPEN_MAIN_JOURNAL
4927      || eType==SQLITE_OPEN_WAL
4928   ));
4929 #endif
4930 
4931   OSTRACE(("OPEN name=%s, pFile=%p, flags=%x, pOutFlags=%p\n",
4932            zUtf8Name, id, flags, pOutFlags));
4933 
4934   /* Check the following statements are true:
4935   **
4936   **   (a) Exactly one of the READWRITE and READONLY flags must be set, and
4937   **   (b) if CREATE is set, then READWRITE must also be set, and
4938   **   (c) if EXCLUSIVE is set, then CREATE must also be set.
4939   **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
4940   */
4941   assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
4942   assert(isCreate==0 || isReadWrite);
4943   assert(isExclusive==0 || isCreate);
4944   assert(isDelete==0 || isCreate);
4945 
4946   /* The main DB, main journal, WAL file and master journal are never
4947   ** automatically deleted. Nor are they ever temporary files.  */
4948   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
4949   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
4950   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
4951   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
4952 
4953   /* Assert that the upper layer has set one of the "file-type" flags. */
4954   assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB
4955        || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL
4956        || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL
4957        || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
4958   );
4959 
4960   assert( pFile!=0 );
4961   memset(pFile, 0, sizeof(winFile));
4962   pFile->h = INVALID_HANDLE_VALUE;
4963 
4964 #if SQLITE_OS_WINRT
4965   if( !zUtf8Name && !sqlite3_temp_directory ){
4966     sqlite3_log(SQLITE_ERROR,
4967         "sqlite3_temp_directory variable should be set for WinRT");
4968   }
4969 #endif
4970 
4971   /* If the second argument to this function is NULL, generate a
4972   ** temporary file name to use
4973   */
4974   if( !zUtf8Name ){
4975     assert( isDelete && !isOpenJournal );
4976     rc = winGetTempname(pVfs, &zTmpname);
4977     if( rc!=SQLITE_OK ){
4978       OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
4979       return rc;
4980     }
4981     zUtf8Name = zTmpname;
4982   }
4983 
4984   /* Database filenames are double-zero terminated if they are not
4985   ** URIs with parameters.  Hence, they can always be passed into
4986   ** sqlite3_uri_parameter().
4987   */
4988   assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
4989        zUtf8Name[sqlite3Strlen30(zUtf8Name)+1]==0 );
4990 
4991   /* Convert the filename to the system encoding. */
4992   zConverted = winConvertFromUtf8Filename(zUtf8Name);
4993   if( zConverted==0 ){
4994     sqlite3_free(zTmpname);
4995     OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
4996     return SQLITE_IOERR_NOMEM_BKPT;
4997   }
4998 
4999   if( winIsDir(zConverted) ){
5000     sqlite3_free(zConverted);
5001     sqlite3_free(zTmpname);
5002     OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
5003     return SQLITE_CANTOPEN_ISDIR;
5004   }
5005 
5006   if( isReadWrite ){
5007     dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
5008   }else{
5009     dwDesiredAccess = GENERIC_READ;
5010   }
5011 
5012   /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is
5013   ** created. SQLite doesn't use it to indicate "exclusive access"
5014   ** as it is usually understood.
5015   */
5016   if( isExclusive ){
5017     /* Creates a new file, only if it does not already exist. */
5018     /* If the file exists, it fails. */
5019     dwCreationDisposition = CREATE_NEW;
5020   }else if( isCreate ){
5021     /* Open existing file, or create if it doesn't exist */
5022     dwCreationDisposition = OPEN_ALWAYS;
5023   }else{
5024     /* Opens a file, only if it exists. */
5025     dwCreationDisposition = OPEN_EXISTING;
5026   }
5027 
5028   dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
5029 
5030   if( isDelete ){
5031 #if SQLITE_OS_WINCE
5032     dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
5033     isTemp = 1;
5034 #else
5035     dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
5036                                | FILE_ATTRIBUTE_HIDDEN
5037                                | FILE_FLAG_DELETE_ON_CLOSE;
5038 #endif
5039   }else{
5040     dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
5041   }
5042   /* Reports from the internet are that performance is always
5043   ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
5044 #if SQLITE_OS_WINCE
5045   dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
5046 #endif
5047 
5048   if( osIsNT() ){
5049 #if SQLITE_OS_WINRT
5050     CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
5051     extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
5052     extendedParameters.dwFileAttributes =
5053             dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
5054     extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
5055     extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
5056     extendedParameters.lpSecurityAttributes = NULL;
5057     extendedParameters.hTemplateFile = NULL;
5058     while( (h = osCreateFile2((LPCWSTR)zConverted,
5059                               dwDesiredAccess,
5060                               dwShareMode,
5061                               dwCreationDisposition,
5062                               &extendedParameters))==INVALID_HANDLE_VALUE &&
5063                               winRetryIoerr(&cnt, &lastErrno) ){
5064                /* Noop */
5065     }
5066 #else
5067     while( (h = osCreateFileW((LPCWSTR)zConverted,
5068                               dwDesiredAccess,
5069                               dwShareMode, NULL,
5070                               dwCreationDisposition,
5071                               dwFlagsAndAttributes,
5072                               NULL))==INVALID_HANDLE_VALUE &&
5073                               winRetryIoerr(&cnt, &lastErrno) ){
5074                /* Noop */
5075     }
5076 #endif
5077   }
5078 #ifdef SQLITE_WIN32_HAS_ANSI
5079   else{
5080     while( (h = osCreateFileA((LPCSTR)zConverted,
5081                               dwDesiredAccess,
5082                               dwShareMode, NULL,
5083                               dwCreationDisposition,
5084                               dwFlagsAndAttributes,
5085                               NULL))==INVALID_HANDLE_VALUE &&
5086                               winRetryIoerr(&cnt, &lastErrno) ){
5087                /* Noop */
5088     }
5089   }
5090 #endif
5091   winLogIoerr(cnt, __LINE__);
5092 
5093   OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
5094            dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
5095 
5096   if( h==INVALID_HANDLE_VALUE ){
5097     pFile->lastErrno = lastErrno;
5098     winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
5099     sqlite3_free(zConverted);
5100     sqlite3_free(zTmpname);
5101     if( isReadWrite && !isExclusive ){
5102       return winOpen(pVfs, zName, id,
5103          ((flags|SQLITE_OPEN_READONLY) &
5104                      ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
5105          pOutFlags);
5106     }else{
5107       return SQLITE_CANTOPEN_BKPT;
5108     }
5109   }
5110 
5111   if( pOutFlags ){
5112     if( isReadWrite ){
5113       *pOutFlags = SQLITE_OPEN_READWRITE;
5114     }else{
5115       *pOutFlags = SQLITE_OPEN_READONLY;
5116     }
5117   }
5118 
5119   OSTRACE(("OPEN file=%p, name=%s, access=%lx, pOutFlags=%p, *pOutFlags=%d, "
5120            "rc=%s\n", h, zUtf8Name, dwDesiredAccess, pOutFlags, pOutFlags ?
5121            *pOutFlags : 0, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
5122 
5123   pAppData = (winVfsAppData*)pVfs->pAppData;
5124 
5125 #if SQLITE_OS_WINCE
5126   {
5127     if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
5128          && ((pAppData==NULL) || !pAppData->bNoLock)
5129          && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
5130     ){
5131       osCloseHandle(h);
5132       sqlite3_free(zConverted);
5133       sqlite3_free(zTmpname);
5134       OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
5135       return rc;
5136     }
5137   }
5138   if( isTemp ){
5139     pFile->zDeleteOnClose = zConverted;
5140   }else
5141 #endif
5142   {
5143     sqlite3_free(zConverted);
5144   }
5145 
5146   sqlite3_free(zTmpname);
5147   pFile->pMethod = pAppData ? pAppData->pMethod : &winIoMethod;
5148   pFile->pVfs = pVfs;
5149   pFile->h = h;
5150   if( isReadonly ){
5151     pFile->ctrlFlags |= WINFILE_RDONLY;
5152   }
5153   if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
5154     pFile->ctrlFlags |= WINFILE_PSOW;
5155   }
5156   pFile->lastErrno = NO_ERROR;
5157   pFile->zPath = zName;
5158 #if SQLITE_MAX_MMAP_SIZE>0
5159   pFile->hMap = NULL;
5160   pFile->pMapRegion = 0;
5161   pFile->mmapSize = 0;
5162   pFile->mmapSizeActual = 0;
5163   pFile->mmapSizeMax = sqlite3GlobalConfig.szMmap;
5164 #endif
5165 
5166   OpenCounter(+1);
5167   return rc;
5168 }
5169 
5170 /*
5171 ** Delete the named file.
5172 **
5173 ** Note that Windows does not allow a file to be deleted if some other
5174 ** process has it open.  Sometimes a virus scanner or indexing program
5175 ** will open a journal file shortly after it is created in order to do
5176 ** whatever it does.  While this other process is holding the
5177 ** file open, we will be unable to delete it.  To work around this
5178 ** problem, we delay 100 milliseconds and try to delete again.  Up
5179 ** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
5180 ** up and returning an error.
5181 */
5182 static int winDelete(
5183   sqlite3_vfs *pVfs,          /* Not used on win32 */
5184   const char *zFilename,      /* Name of file to delete */
5185   int syncDir                 /* Not used on win32 */
5186 ){
5187   int cnt = 0;
5188   int rc;
5189   DWORD attr;
5190   DWORD lastErrno = 0;
5191   void *zConverted;
5192   UNUSED_PARAMETER(pVfs);
5193   UNUSED_PARAMETER(syncDir);
5194 
5195   SimulateIOError(return SQLITE_IOERR_DELETE);
5196   OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));
5197 
5198   zConverted = winConvertFromUtf8Filename(zFilename);
5199   if( zConverted==0 ){
5200     OSTRACE(("DELETE name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
5201     return SQLITE_IOERR_NOMEM_BKPT;
5202   }
5203   if( osIsNT() ){
5204     do {
5205 #if SQLITE_OS_WINRT
5206       WIN32_FILE_ATTRIBUTE_DATA sAttrData;
5207       memset(&sAttrData, 0, sizeof(sAttrData));
5208       if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
5209                                   &sAttrData) ){
5210         attr = sAttrData.dwFileAttributes;
5211       }else{
5212         lastErrno = osGetLastError();
5213         if( lastErrno==ERROR_FILE_NOT_FOUND
5214          || lastErrno==ERROR_PATH_NOT_FOUND ){
5215           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
5216         }else{
5217           rc = SQLITE_ERROR;
5218         }
5219         break;
5220       }
5221 #else
5222       attr = osGetFileAttributesW(zConverted);
5223 #endif
5224       if ( attr==INVALID_FILE_ATTRIBUTES ){
5225         lastErrno = osGetLastError();
5226         if( lastErrno==ERROR_FILE_NOT_FOUND
5227          || lastErrno==ERROR_PATH_NOT_FOUND ){
5228           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
5229         }else{
5230           rc = SQLITE_ERROR;
5231         }
5232         break;
5233       }
5234       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
5235         rc = SQLITE_ERROR; /* Files only. */
5236         break;
5237       }
5238       if ( osDeleteFileW(zConverted) ){
5239         rc = SQLITE_OK; /* Deleted OK. */
5240         break;
5241       }
5242       if ( !winRetryIoerr(&cnt, &lastErrno) ){
5243         rc = SQLITE_ERROR; /* No more retries. */
5244         break;
5245       }
5246     } while(1);
5247   }
5248 #ifdef SQLITE_WIN32_HAS_ANSI
5249   else{
5250     do {
5251       attr = osGetFileAttributesA(zConverted);
5252       if ( attr==INVALID_FILE_ATTRIBUTES ){
5253         lastErrno = osGetLastError();
5254         if( lastErrno==ERROR_FILE_NOT_FOUND
5255          || lastErrno==ERROR_PATH_NOT_FOUND ){
5256           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
5257         }else{
5258           rc = SQLITE_ERROR;
5259         }
5260         break;
5261       }
5262       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
5263         rc = SQLITE_ERROR; /* Files only. */
5264         break;
5265       }
5266       if ( osDeleteFileA(zConverted) ){
5267         rc = SQLITE_OK; /* Deleted OK. */
5268         break;
5269       }
5270       if ( !winRetryIoerr(&cnt, &lastErrno) ){
5271         rc = SQLITE_ERROR; /* No more retries. */
5272         break;
5273       }
5274     } while(1);
5275   }
5276 #endif
5277   if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
5278     rc = winLogError(SQLITE_IOERR_DELETE, lastErrno, "winDelete", zFilename);
5279   }else{
5280     winLogIoerr(cnt, __LINE__);
5281   }
5282   sqlite3_free(zConverted);
5283   OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
5284   return rc;
5285 }
5286 
5287 /*
5288 ** Check the existence and status of a file.
5289 */
5290 static int winAccess(
5291   sqlite3_vfs *pVfs,         /* Not used on win32 */
5292   const char *zFilename,     /* Name of file to check */
5293   int flags,                 /* Type of test to make on this file */
5294   int *pResOut               /* OUT: Result */
5295 ){
5296   DWORD attr;
5297   int rc = 0;
5298   DWORD lastErrno = 0;
5299   void *zConverted;
5300   UNUSED_PARAMETER(pVfs);
5301 
5302   SimulateIOError( return SQLITE_IOERR_ACCESS; );
5303   OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
5304            zFilename, flags, pResOut));
5305 
5306   zConverted = winConvertFromUtf8Filename(zFilename);
5307   if( zConverted==0 ){
5308     OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
5309     return SQLITE_IOERR_NOMEM_BKPT;
5310   }
5311   if( osIsNT() ){
5312     int cnt = 0;
5313     WIN32_FILE_ATTRIBUTE_DATA sAttrData;
5314     memset(&sAttrData, 0, sizeof(sAttrData));
5315     while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
5316                              GetFileExInfoStandard,
5317                              &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
5318     if( rc ){
5319       /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
5320       ** as if it does not exist.
5321       */
5322       if(    flags==SQLITE_ACCESS_EXISTS
5323           && sAttrData.nFileSizeHigh==0
5324           && sAttrData.nFileSizeLow==0 ){
5325         attr = INVALID_FILE_ATTRIBUTES;
5326       }else{
5327         attr = sAttrData.dwFileAttributes;
5328       }
5329     }else{
5330       winLogIoerr(cnt, __LINE__);
5331       if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
5332         sqlite3_free(zConverted);
5333         return winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess",
5334                            zFilename);
5335       }else{
5336         attr = INVALID_FILE_ATTRIBUTES;
5337       }
5338     }
5339   }
5340 #ifdef SQLITE_WIN32_HAS_ANSI
5341   else{
5342     attr = osGetFileAttributesA((char*)zConverted);
5343   }
5344 #endif
5345   sqlite3_free(zConverted);
5346   switch( flags ){
5347     case SQLITE_ACCESS_READ:
5348     case SQLITE_ACCESS_EXISTS:
5349       rc = attr!=INVALID_FILE_ATTRIBUTES;
5350       break;
5351     case SQLITE_ACCESS_READWRITE:
5352       rc = attr!=INVALID_FILE_ATTRIBUTES &&
5353              (attr & FILE_ATTRIBUTE_READONLY)==0;
5354       break;
5355     default:
5356       assert(!"Invalid flags argument");
5357   }
5358   *pResOut = rc;
5359   OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
5360            zFilename, pResOut, *pResOut));
5361   return SQLITE_OK;
5362 }
5363 
5364 /*
5365 ** Returns non-zero if the specified path name starts with a drive letter
5366 ** followed by a colon character.
5367 */
5368 static BOOL winIsDriveLetterAndColon(
5369   const char *zPathname
5370 ){
5371   return ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' );
5372 }
5373 
5374 /*
5375 ** Returns non-zero if the specified path name should be used verbatim.  If
5376 ** non-zero is returned from this function, the calling function must simply
5377 ** use the provided path name verbatim -OR- resolve it into a full path name
5378 ** using the GetFullPathName Win32 API function (if available).
5379 */
5380 static BOOL winIsVerbatimPathname(
5381   const char *zPathname
5382 ){
5383   /*
5384   ** If the path name starts with a forward slash or a backslash, it is either
5385   ** a legal UNC name, a volume relative path, or an absolute path name in the
5386   ** "Unix" format on Windows.  There is no easy way to differentiate between
5387   ** the final two cases; therefore, we return the safer return value of TRUE
5388   ** so that callers of this function will simply use it verbatim.
5389   */
5390   if ( winIsDirSep(zPathname[0]) ){
5391     return TRUE;
5392   }
5393 
5394   /*
5395   ** If the path name starts with a letter and a colon it is either a volume
5396   ** relative path or an absolute path.  Callers of this function must not
5397   ** attempt to treat it as a relative path name (i.e. they should simply use
5398   ** it verbatim).
5399   */
5400   if ( winIsDriveLetterAndColon(zPathname) ){
5401     return TRUE;
5402   }
5403 
5404   /*
5405   ** If we get to this point, the path name should almost certainly be a purely
5406   ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
5407   */
5408   return FALSE;
5409 }
5410 
5411 /*
5412 ** Turn a relative pathname into a full pathname.  Write the full
5413 ** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
5414 ** bytes in size.
5415 */
5416 static int winFullPathname(
5417   sqlite3_vfs *pVfs,            /* Pointer to vfs object */
5418   const char *zRelative,        /* Possibly relative input path */
5419   int nFull,                    /* Size of output buffer in bytes */
5420   char *zFull                   /* Output buffer */
5421 ){
5422 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
5423   DWORD nByte;
5424   void *zConverted;
5425   char *zOut;
5426 #endif
5427 
5428   /* If this path name begins with "/X:", where "X" is any alphabetic
5429   ** character, discard the initial "/" from the pathname.
5430   */
5431   if( zRelative[0]=='/' && winIsDriveLetterAndColon(zRelative+1) ){
5432     zRelative++;
5433   }
5434 
5435 #if defined(__CYGWIN__)
5436   SimulateIOError( return SQLITE_ERROR );
5437   UNUSED_PARAMETER(nFull);
5438   assert( nFull>=pVfs->mxPathname );
5439   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5440     /*
5441     ** NOTE: We are dealing with a relative path name and the data
5442     **       directory has been set.  Therefore, use it as the basis
5443     **       for converting the relative path name to an absolute
5444     **       one by prepending the data directory and a slash.
5445     */
5446     char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
5447     if( !zOut ){
5448       return SQLITE_IOERR_NOMEM_BKPT;
5449     }
5450     if( cygwin_conv_path(
5451             (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A) |
5452             CCP_RELATIVE, zRelative, zOut, pVfs->mxPathname+1)<0 ){
5453       sqlite3_free(zOut);
5454       return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
5455                          "winFullPathname1", zRelative);
5456     }else{
5457       char *zUtf8 = winConvertToUtf8Filename(zOut);
5458       if( !zUtf8 ){
5459         sqlite3_free(zOut);
5460         return SQLITE_IOERR_NOMEM_BKPT;
5461       }
5462       sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5463                        sqlite3_data_directory, winGetDirSep(), zUtf8);
5464       sqlite3_free(zUtf8);
5465       sqlite3_free(zOut);
5466     }
5467   }else{
5468     char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
5469     if( !zOut ){
5470       return SQLITE_IOERR_NOMEM_BKPT;
5471     }
5472     if( cygwin_conv_path(
5473             (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A),
5474             zRelative, zOut, pVfs->mxPathname+1)<0 ){
5475       sqlite3_free(zOut);
5476       return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
5477                          "winFullPathname2", zRelative);
5478     }else{
5479       char *zUtf8 = winConvertToUtf8Filename(zOut);
5480       if( !zUtf8 ){
5481         sqlite3_free(zOut);
5482         return SQLITE_IOERR_NOMEM_BKPT;
5483       }
5484       sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zUtf8);
5485       sqlite3_free(zUtf8);
5486       sqlite3_free(zOut);
5487     }
5488   }
5489   return SQLITE_OK;
5490 #endif
5491 
5492 #if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
5493   SimulateIOError( return SQLITE_ERROR );
5494   /* WinCE has no concept of a relative pathname, or so I am told. */
5495   /* WinRT has no way to convert a relative path to an absolute one. */
5496   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5497     /*
5498     ** NOTE: We are dealing with a relative path name and the data
5499     **       directory has been set.  Therefore, use it as the basis
5500     **       for converting the relative path name to an absolute
5501     **       one by prepending the data directory and a backslash.
5502     */
5503     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5504                      sqlite3_data_directory, winGetDirSep(), zRelative);
5505   }else{
5506     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
5507   }
5508   return SQLITE_OK;
5509 #endif
5510 
5511 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
5512   /* It's odd to simulate an io-error here, but really this is just
5513   ** using the io-error infrastructure to test that SQLite handles this
5514   ** function failing. This function could fail if, for example, the
5515   ** current working directory has been unlinked.
5516   */
5517   SimulateIOError( return SQLITE_ERROR );
5518   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5519     /*
5520     ** NOTE: We are dealing with a relative path name and the data
5521     **       directory has been set.  Therefore, use it as the basis
5522     **       for converting the relative path name to an absolute
5523     **       one by prepending the data directory and a backslash.
5524     */
5525     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5526                      sqlite3_data_directory, winGetDirSep(), zRelative);
5527     return SQLITE_OK;
5528   }
5529   zConverted = winConvertFromUtf8Filename(zRelative);
5530   if( zConverted==0 ){
5531     return SQLITE_IOERR_NOMEM_BKPT;
5532   }
5533   if( osIsNT() ){
5534     LPWSTR zTemp;
5535     nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
5536     if( nByte==0 ){
5537       sqlite3_free(zConverted);
5538       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5539                          "winFullPathname1", zRelative);
5540     }
5541     nByte += 3;
5542     zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
5543     if( zTemp==0 ){
5544       sqlite3_free(zConverted);
5545       return SQLITE_IOERR_NOMEM_BKPT;
5546     }
5547     nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
5548     if( nByte==0 ){
5549       sqlite3_free(zConverted);
5550       sqlite3_free(zTemp);
5551       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5552                          "winFullPathname2", zRelative);
5553     }
5554     sqlite3_free(zConverted);
5555     zOut = winUnicodeToUtf8(zTemp);
5556     sqlite3_free(zTemp);
5557   }
5558 #ifdef SQLITE_WIN32_HAS_ANSI
5559   else{
5560     char *zTemp;
5561     nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
5562     if( nByte==0 ){
5563       sqlite3_free(zConverted);
5564       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5565                          "winFullPathname3", zRelative);
5566     }
5567     nByte += 3;
5568     zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
5569     if( zTemp==0 ){
5570       sqlite3_free(zConverted);
5571       return SQLITE_IOERR_NOMEM_BKPT;
5572     }
5573     nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
5574     if( nByte==0 ){
5575       sqlite3_free(zConverted);
5576       sqlite3_free(zTemp);
5577       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5578                          "winFullPathname4", zRelative);
5579     }
5580     sqlite3_free(zConverted);
5581     zOut = winMbcsToUtf8(zTemp, osAreFileApisANSI());
5582     sqlite3_free(zTemp);
5583   }
5584 #endif
5585   if( zOut ){
5586     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zOut);
5587     sqlite3_free(zOut);
5588     return SQLITE_OK;
5589   }else{
5590     return SQLITE_IOERR_NOMEM_BKPT;
5591   }
5592 #endif
5593 }
5594 
5595 #ifndef SQLITE_OMIT_LOAD_EXTENSION
5596 /*
5597 ** Interfaces for opening a shared library, finding entry points
5598 ** within the shared library, and closing the shared library.
5599 */
5600 static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
5601   HANDLE h;
5602 #if defined(__CYGWIN__)
5603   int nFull = pVfs->mxPathname+1;
5604   char *zFull = sqlite3MallocZero( nFull );
5605   void *zConverted = 0;
5606   if( zFull==0 ){
5607     OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
5608     return 0;
5609   }
5610   if( winFullPathname(pVfs, zFilename, nFull, zFull)!=SQLITE_OK ){
5611     sqlite3_free(zFull);
5612     OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
5613     return 0;
5614   }
5615   zConverted = winConvertFromUtf8Filename(zFull);
5616   sqlite3_free(zFull);
5617 #else
5618   void *zConverted = winConvertFromUtf8Filename(zFilename);
5619   UNUSED_PARAMETER(pVfs);
5620 #endif
5621   if( zConverted==0 ){
5622     OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
5623     return 0;
5624   }
5625   if( osIsNT() ){
5626 #if SQLITE_OS_WINRT
5627     h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
5628 #else
5629     h = osLoadLibraryW((LPCWSTR)zConverted);
5630 #endif
5631   }
5632 #ifdef SQLITE_WIN32_HAS_ANSI
5633   else{
5634     h = osLoadLibraryA((char*)zConverted);
5635   }
5636 #endif
5637   OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)h));
5638   sqlite3_free(zConverted);
5639   return (void*)h;
5640 }
5641 static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
5642   UNUSED_PARAMETER(pVfs);
5643   winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
5644 }
5645 static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
5646   FARPROC proc;
5647   UNUSED_PARAMETER(pVfs);
5648   proc = osGetProcAddressA((HANDLE)pH, zSym);
5649   OSTRACE(("DLSYM handle=%p, symbol=%s, address=%p\n",
5650            (void*)pH, zSym, (void*)proc));
5651   return (void(*)(void))proc;
5652 }
5653 static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
5654   UNUSED_PARAMETER(pVfs);
5655   osFreeLibrary((HANDLE)pHandle);
5656   OSTRACE(("DLCLOSE handle=%p\n", (void*)pHandle));
5657 }
5658 #else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
5659   #define winDlOpen  0
5660   #define winDlError 0
5661   #define winDlSym   0
5662   #define winDlClose 0
5663 #endif
5664 
5665 /* State information for the randomness gatherer. */
5666 typedef struct EntropyGatherer EntropyGatherer;
5667 struct EntropyGatherer {
5668   unsigned char *a;   /* Gather entropy into this buffer */
5669   int na;             /* Size of a[] in bytes */
5670   int i;              /* XOR next input into a[i] */
5671   int nXor;           /* Number of XOR operations done */
5672 };
5673 
5674 #if !defined(SQLITE_TEST) && !defined(SQLITE_OMIT_RANDOMNESS)
5675 /* Mix sz bytes of entropy into p. */
5676 static void xorMemory(EntropyGatherer *p, unsigned char *x, int sz){
5677   int j, k;
5678   for(j=0, k=p->i; j<sz; j++){
5679     p->a[k++] ^= x[j];
5680     if( k>=p->na ) k = 0;
5681   }
5682   p->i = k;
5683   p->nXor += sz;
5684 }
5685 #endif /* !defined(SQLITE_TEST) && !defined(SQLITE_OMIT_RANDOMNESS) */
5686 
5687 /*
5688 ** Write up to nBuf bytes of randomness into zBuf.
5689 */
5690 static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5691 #if defined(SQLITE_TEST) || defined(SQLITE_OMIT_RANDOMNESS)
5692   UNUSED_PARAMETER(pVfs);
5693   memset(zBuf, 0, nBuf);
5694   return nBuf;
5695 #else
5696   EntropyGatherer e;
5697   UNUSED_PARAMETER(pVfs);
5698   memset(zBuf, 0, nBuf);
5699 #if defined(_MSC_VER) && _MSC_VER>=1400 && !SQLITE_OS_WINCE
5700   rand_s((unsigned int*)zBuf); /* rand_s() is not available with MinGW */
5701 #endif /* defined(_MSC_VER) && _MSC_VER>=1400 */
5702   e.a = (unsigned char*)zBuf;
5703   e.na = nBuf;
5704   e.nXor = 0;
5705   e.i = 0;
5706   {
5707     SYSTEMTIME x;
5708     osGetSystemTime(&x);
5709     xorMemory(&e, (unsigned char*)&x, sizeof(SYSTEMTIME));
5710   }
5711   {
5712     DWORD pid = osGetCurrentProcessId();
5713     xorMemory(&e, (unsigned char*)&pid, sizeof(DWORD));
5714   }
5715 #if SQLITE_OS_WINRT
5716   {
5717     ULONGLONG cnt = osGetTickCount64();
5718     xorMemory(&e, (unsigned char*)&cnt, sizeof(ULONGLONG));
5719   }
5720 #else
5721   {
5722     DWORD cnt = osGetTickCount();
5723     xorMemory(&e, (unsigned char*)&cnt, sizeof(DWORD));
5724   }
5725 #endif /* SQLITE_OS_WINRT */
5726   {
5727     LARGE_INTEGER i;
5728     osQueryPerformanceCounter(&i);
5729     xorMemory(&e, (unsigned char*)&i, sizeof(LARGE_INTEGER));
5730   }
5731 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
5732   {
5733     UUID id;
5734     memset(&id, 0, sizeof(UUID));
5735     osUuidCreate(&id);
5736     xorMemory(&e, (unsigned char*)&id, sizeof(UUID));
5737     memset(&id, 0, sizeof(UUID));
5738     osUuidCreateSequential(&id);
5739     xorMemory(&e, (unsigned char*)&id, sizeof(UUID));
5740   }
5741 #endif /* !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID */
5742   return e.nXor>nBuf ? nBuf : e.nXor;
5743 #endif /* defined(SQLITE_TEST) || defined(SQLITE_OMIT_RANDOMNESS) */
5744 }
5745 
5746 
5747 /*
5748 ** Sleep for a little while.  Return the amount of time slept.
5749 */
5750 static int winSleep(sqlite3_vfs *pVfs, int microsec){
5751   sqlite3_win32_sleep((microsec+999)/1000);
5752   UNUSED_PARAMETER(pVfs);
5753   return ((microsec+999)/1000)*1000;
5754 }
5755 
5756 /*
5757 ** The following variable, if set to a non-zero value, is interpreted as
5758 ** the number of seconds since 1970 and is used to set the result of
5759 ** sqlite3OsCurrentTime() during testing.
5760 */
5761 #ifdef SQLITE_TEST
5762 int sqlite3_current_time = 0;  /* Fake system time in seconds since 1970. */
5763 #endif
5764 
5765 /*
5766 ** Find the current time (in Universal Coordinated Time).  Write into *piNow
5767 ** the current time and date as a Julian Day number times 86_400_000.  In
5768 ** other words, write into *piNow the number of milliseconds since the Julian
5769 ** epoch of noon in Greenwich on November 24, 4714 B.C according to the
5770 ** proleptic Gregorian calendar.
5771 **
5772 ** On success, return SQLITE_OK.  Return SQLITE_ERROR if the time and date
5773 ** cannot be found.
5774 */
5775 static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
5776   /* FILETIME structure is a 64-bit value representing the number of
5777      100-nanosecond intervals since January 1, 1601 (= JD 2305813.5).
5778   */
5779   FILETIME ft;
5780   static const sqlite3_int64 winFiletimeEpoch = 23058135*(sqlite3_int64)8640000;
5781 #ifdef SQLITE_TEST
5782   static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
5783 #endif
5784   /* 2^32 - to avoid use of LL and warnings in gcc */
5785   static const sqlite3_int64 max32BitValue =
5786       (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 +
5787       (sqlite3_int64)294967296;
5788 
5789 #if SQLITE_OS_WINCE
5790   SYSTEMTIME time;
5791   osGetSystemTime(&time);
5792   /* if SystemTimeToFileTime() fails, it returns zero. */
5793   if (!osSystemTimeToFileTime(&time,&ft)){
5794     return SQLITE_ERROR;
5795   }
5796 #else
5797   osGetSystemTimeAsFileTime( &ft );
5798 #endif
5799 
5800   *piNow = winFiletimeEpoch +
5801             ((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) +
5802                (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000;
5803 
5804 #ifdef SQLITE_TEST
5805   if( sqlite3_current_time ){
5806     *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
5807   }
5808 #endif
5809   UNUSED_PARAMETER(pVfs);
5810   return SQLITE_OK;
5811 }
5812 
5813 /*
5814 ** Find the current time (in Universal Coordinated Time).  Write the
5815 ** current time and date as a Julian Day number into *prNow and
5816 ** return 0.  Return 1 if the time and date cannot be found.
5817 */
5818 static int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
5819   int rc;
5820   sqlite3_int64 i;
5821   rc = winCurrentTimeInt64(pVfs, &i);
5822   if( !rc ){
5823     *prNow = i/86400000.0;
5824   }
5825   return rc;
5826 }
5827 
5828 /*
5829 ** The idea is that this function works like a combination of
5830 ** GetLastError() and FormatMessage() on Windows (or errno and
5831 ** strerror_r() on Unix). After an error is returned by an OS
5832 ** function, SQLite calls this function with zBuf pointing to
5833 ** a buffer of nBuf bytes. The OS layer should populate the
5834 ** buffer with a nul-terminated UTF-8 encoded error message
5835 ** describing the last IO error to have occurred within the calling
5836 ** thread.
5837 **
5838 ** If the error message is too large for the supplied buffer,
5839 ** it should be truncated. The return value of xGetLastError
5840 ** is zero if the error message fits in the buffer, or non-zero
5841 ** otherwise (if the message was truncated). If non-zero is returned,
5842 ** then it is not necessary to include the nul-terminator character
5843 ** in the output buffer.
5844 **
5845 ** Not supplying an error message will have no adverse effect
5846 ** on SQLite. It is fine to have an implementation that never
5847 ** returns an error message:
5848 **
5849 **   int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5850 **     assert(zBuf[0]=='\0');
5851 **     return 0;
5852 **   }
5853 **
5854 ** However if an error message is supplied, it will be incorporated
5855 ** by sqlite into the error message available to the user using
5856 ** sqlite3_errmsg(), possibly making IO errors easier to debug.
5857 */
5858 static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5859   DWORD e = osGetLastError();
5860   UNUSED_PARAMETER(pVfs);
5861   if( nBuf>0 ) winGetLastErrorMsg(e, nBuf, zBuf);
5862   return e;
5863 }
5864 
5865 /*
5866 ** Initialize and deinitialize the operating system interface.
5867 */
5868 int sqlite3_os_init(void){
5869   static sqlite3_vfs winVfs = {
5870     3,                     /* iVersion */
5871     sizeof(winFile),       /* szOsFile */
5872     SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
5873     0,                     /* pNext */
5874     "win32",               /* zName */
5875     &winAppData,           /* pAppData */
5876     winOpen,               /* xOpen */
5877     winDelete,             /* xDelete */
5878     winAccess,             /* xAccess */
5879     winFullPathname,       /* xFullPathname */
5880     winDlOpen,             /* xDlOpen */
5881     winDlError,            /* xDlError */
5882     winDlSym,              /* xDlSym */
5883     winDlClose,            /* xDlClose */
5884     winRandomness,         /* xRandomness */
5885     winSleep,              /* xSleep */
5886     winCurrentTime,        /* xCurrentTime */
5887     winGetLastError,       /* xGetLastError */
5888     winCurrentTimeInt64,   /* xCurrentTimeInt64 */
5889     winSetSystemCall,      /* xSetSystemCall */
5890     winGetSystemCall,      /* xGetSystemCall */
5891     winNextSystemCall,     /* xNextSystemCall */
5892   };
5893 #if defined(SQLITE_WIN32_HAS_WIDE)
5894   static sqlite3_vfs winLongPathVfs = {
5895     3,                     /* iVersion */
5896     sizeof(winFile),       /* szOsFile */
5897     SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
5898     0,                     /* pNext */
5899     "win32-longpath",      /* zName */
5900     &winAppData,           /* pAppData */
5901     winOpen,               /* xOpen */
5902     winDelete,             /* xDelete */
5903     winAccess,             /* xAccess */
5904     winFullPathname,       /* xFullPathname */
5905     winDlOpen,             /* xDlOpen */
5906     winDlError,            /* xDlError */
5907     winDlSym,              /* xDlSym */
5908     winDlClose,            /* xDlClose */
5909     winRandomness,         /* xRandomness */
5910     winSleep,              /* xSleep */
5911     winCurrentTime,        /* xCurrentTime */
5912     winGetLastError,       /* xGetLastError */
5913     winCurrentTimeInt64,   /* xCurrentTimeInt64 */
5914     winSetSystemCall,      /* xSetSystemCall */
5915     winGetSystemCall,      /* xGetSystemCall */
5916     winNextSystemCall,     /* xNextSystemCall */
5917   };
5918 #endif
5919   static sqlite3_vfs winNolockVfs = {
5920     3,                     /* iVersion */
5921     sizeof(winFile),       /* szOsFile */
5922     SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
5923     0,                     /* pNext */
5924     "win32-none",          /* zName */
5925     &winNolockAppData,     /* pAppData */
5926     winOpen,               /* xOpen */
5927     winDelete,             /* xDelete */
5928     winAccess,             /* xAccess */
5929     winFullPathname,       /* xFullPathname */
5930     winDlOpen,             /* xDlOpen */
5931     winDlError,            /* xDlError */
5932     winDlSym,              /* xDlSym */
5933     winDlClose,            /* xDlClose */
5934     winRandomness,         /* xRandomness */
5935     winSleep,              /* xSleep */
5936     winCurrentTime,        /* xCurrentTime */
5937     winGetLastError,       /* xGetLastError */
5938     winCurrentTimeInt64,   /* xCurrentTimeInt64 */
5939     winSetSystemCall,      /* xSetSystemCall */
5940     winGetSystemCall,      /* xGetSystemCall */
5941     winNextSystemCall,     /* xNextSystemCall */
5942   };
5943 #if defined(SQLITE_WIN32_HAS_WIDE)
5944   static sqlite3_vfs winLongPathNolockVfs = {
5945     3,                     /* iVersion */
5946     sizeof(winFile),       /* szOsFile */
5947     SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
5948     0,                     /* pNext */
5949     "win32-longpath-none", /* zName */
5950     &winNolockAppData,     /* pAppData */
5951     winOpen,               /* xOpen */
5952     winDelete,             /* xDelete */
5953     winAccess,             /* xAccess */
5954     winFullPathname,       /* xFullPathname */
5955     winDlOpen,             /* xDlOpen */
5956     winDlError,            /* xDlError */
5957     winDlSym,              /* xDlSym */
5958     winDlClose,            /* xDlClose */
5959     winRandomness,         /* xRandomness */
5960     winSleep,              /* xSleep */
5961     winCurrentTime,        /* xCurrentTime */
5962     winGetLastError,       /* xGetLastError */
5963     winCurrentTimeInt64,   /* xCurrentTimeInt64 */
5964     winSetSystemCall,      /* xSetSystemCall */
5965     winGetSystemCall,      /* xGetSystemCall */
5966     winNextSystemCall,     /* xNextSystemCall */
5967   };
5968 #endif
5969 
5970   /* Double-check that the aSyscall[] array has been constructed
5971   ** correctly.  See ticket [bb3a86e890c8e96ab] */
5972   assert( ArraySize(aSyscall)==80 );
5973 
5974   /* get memory map allocation granularity */
5975   memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
5976 #if SQLITE_OS_WINRT
5977   osGetNativeSystemInfo(&winSysInfo);
5978 #else
5979   osGetSystemInfo(&winSysInfo);
5980 #endif
5981   assert( winSysInfo.dwAllocationGranularity>0 );
5982   assert( winSysInfo.dwPageSize>0 );
5983 
5984   sqlite3_vfs_register(&winVfs, 1);
5985 
5986 #if defined(SQLITE_WIN32_HAS_WIDE)
5987   sqlite3_vfs_register(&winLongPathVfs, 0);
5988 #endif
5989 
5990   sqlite3_vfs_register(&winNolockVfs, 0);
5991 
5992 #if defined(SQLITE_WIN32_HAS_WIDE)
5993   sqlite3_vfs_register(&winLongPathNolockVfs, 0);
5994 #endif
5995 
5996   return SQLITE_OK;
5997 }
5998 
5999 int sqlite3_os_end(void){
6000 #if SQLITE_OS_WINRT
6001   if( sleepObj!=NULL ){
6002     osCloseHandle(sleepObj);
6003     sleepObj = NULL;
6004   }
6005 #endif
6006   return SQLITE_OK;
6007 }
6008 
6009 #endif /* SQLITE_OS_WIN */
6010