xref: /sqlite-3.40.0/src/os_win.c (revision ef480d37)
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 ** Allowed values for winFile.ctrlFlags
295 */
296 #define WINFILE_RDONLY          0x02   /* Connection is read only */
297 #define WINFILE_PERSIST_WAL     0x04   /* Persistent WAL mode */
298 #define WINFILE_PSOW            0x10   /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
299 
300 /*
301  * The size of the buffer used by sqlite3_win32_write_debug().
302  */
303 #ifndef SQLITE_WIN32_DBG_BUF_SIZE
304 #  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
305 #endif
306 
307 /*
308  * The value used with sqlite3_win32_set_directory() to specify that
309  * the data directory should be changed.
310  */
311 #ifndef SQLITE_WIN32_DATA_DIRECTORY_TYPE
312 #  define SQLITE_WIN32_DATA_DIRECTORY_TYPE (1)
313 #endif
314 
315 /*
316  * The value used with sqlite3_win32_set_directory() to specify that
317  * the temporary directory should be changed.
318  */
319 #ifndef SQLITE_WIN32_TEMP_DIRECTORY_TYPE
320 #  define SQLITE_WIN32_TEMP_DIRECTORY_TYPE (2)
321 #endif
322 
323 /*
324  * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
325  * various Win32 API heap functions instead of our own.
326  */
327 #ifdef SQLITE_WIN32_MALLOC
328 
329 /*
330  * If this is non-zero, an isolated heap will be created by the native Win32
331  * allocator subsystem; otherwise, the default process heap will be used.  This
332  * setting has no effect when compiling for WinRT.  By default, this is enabled
333  * and an isolated heap will be created to store all allocated data.
334  *
335  ******************************************************************************
336  * WARNING: It is important to note that when this setting is non-zero and the
337  *          winMemShutdown function is called (e.g. by the sqlite3_shutdown
338  *          function), all data that was allocated using the isolated heap will
339  *          be freed immediately and any attempt to access any of that freed
340  *          data will almost certainly result in an immediate access violation.
341  ******************************************************************************
342  */
343 #ifndef SQLITE_WIN32_HEAP_CREATE
344 #  define SQLITE_WIN32_HEAP_CREATE    (TRUE)
345 #endif
346 
347 /*
348  * The initial size of the Win32-specific heap.  This value may be zero.
349  */
350 #ifndef SQLITE_WIN32_HEAP_INIT_SIZE
351 #  define SQLITE_WIN32_HEAP_INIT_SIZE ((SQLITE_DEFAULT_CACHE_SIZE) * \
352                                        (SQLITE_DEFAULT_PAGE_SIZE) + 4194304)
353 #endif
354 
355 /*
356  * The maximum size of the Win32-specific heap.  This value may be zero.
357  */
358 #ifndef SQLITE_WIN32_HEAP_MAX_SIZE
359 #  define SQLITE_WIN32_HEAP_MAX_SIZE  (0)
360 #endif
361 
362 /*
363  * The extra flags to use in calls to the Win32 heap APIs.  This value may be
364  * zero for the default behavior.
365  */
366 #ifndef SQLITE_WIN32_HEAP_FLAGS
367 #  define SQLITE_WIN32_HEAP_FLAGS     (0)
368 #endif
369 
370 
371 /*
372 ** The winMemData structure stores information required by the Win32-specific
373 ** sqlite3_mem_methods implementation.
374 */
375 typedef struct winMemData winMemData;
376 struct winMemData {
377 #ifndef NDEBUG
378   u32 magic1;   /* Magic number to detect structure corruption. */
379 #endif
380   HANDLE hHeap; /* The handle to our heap. */
381   BOOL bOwned;  /* Do we own the heap (i.e. destroy it on shutdown)? */
382 #ifndef NDEBUG
383   u32 magic2;   /* Magic number to detect structure corruption. */
384 #endif
385 };
386 
387 #ifndef NDEBUG
388 #define WINMEM_MAGIC1     0x42b2830b
389 #define WINMEM_MAGIC2     0xbd4d7cf4
390 #endif
391 
392 static struct winMemData win_mem_data = {
393 #ifndef NDEBUG
394   WINMEM_MAGIC1,
395 #endif
396   NULL, FALSE
397 #ifndef NDEBUG
398   ,WINMEM_MAGIC2
399 #endif
400 };
401 
402 #ifndef NDEBUG
403 #define winMemAssertMagic1() assert( win_mem_data.magic1==WINMEM_MAGIC1 )
404 #define winMemAssertMagic2() assert( win_mem_data.magic2==WINMEM_MAGIC2 )
405 #define winMemAssertMagic()  winMemAssertMagic1(); winMemAssertMagic2();
406 #else
407 #define winMemAssertMagic()
408 #endif
409 
410 #define winMemGetDataPtr()  &win_mem_data
411 #define winMemGetHeap()     win_mem_data.hHeap
412 #define winMemGetOwned()    win_mem_data.bOwned
413 
414 static void *winMemMalloc(int nBytes);
415 static void winMemFree(void *pPrior);
416 static void *winMemRealloc(void *pPrior, int nBytes);
417 static int winMemSize(void *p);
418 static int winMemRoundup(int n);
419 static int winMemInit(void *pAppData);
420 static void winMemShutdown(void *pAppData);
421 
422 const sqlite3_mem_methods *sqlite3MemGetWin32(void);
423 #endif /* SQLITE_WIN32_MALLOC */
424 
425 /*
426 ** The following variable is (normally) set once and never changes
427 ** thereafter.  It records whether the operating system is Win9x
428 ** or WinNT.
429 **
430 ** 0:   Operating system unknown.
431 ** 1:   Operating system is Win9x.
432 ** 2:   Operating system is WinNT.
433 **
434 ** In order to facilitate testing on a WinNT system, the test fixture
435 ** can manually set this value to 1 to emulate Win98 behavior.
436 */
437 #ifdef SQLITE_TEST
438 LONG SQLITE_WIN32_VOLATILE sqlite3_os_type = 0;
439 #else
440 static LONG SQLITE_WIN32_VOLATILE sqlite3_os_type = 0;
441 #endif
442 
443 #ifndef SYSCALL
444 #  define SYSCALL sqlite3_syscall_ptr
445 #endif
446 
447 /*
448 ** This function is not available on Windows CE or WinRT.
449  */
450 
451 #if SQLITE_OS_WINCE || SQLITE_OS_WINRT
452 #  define osAreFileApisANSI()       1
453 #endif
454 
455 /*
456 ** Many system calls are accessed through pointer-to-functions so that
457 ** they may be overridden at runtime to facilitate fault injection during
458 ** testing and sandboxing.  The following array holds the names and pointers
459 ** to all overrideable system calls.
460 */
461 static struct win_syscall {
462   const char *zName;            /* Name of the system call */
463   sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
464   sqlite3_syscall_ptr pDefault; /* Default value */
465 } aSyscall[] = {
466 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
467   { "AreFileApisANSI",         (SYSCALL)AreFileApisANSI,         0 },
468 #else
469   { "AreFileApisANSI",         (SYSCALL)0,                       0 },
470 #endif
471 
472 #ifndef osAreFileApisANSI
473 #define osAreFileApisANSI ((BOOL(WINAPI*)(VOID))aSyscall[0].pCurrent)
474 #endif
475 
476 #if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
477   { "CharLowerW",              (SYSCALL)CharLowerW,              0 },
478 #else
479   { "CharLowerW",              (SYSCALL)0,                       0 },
480 #endif
481 
482 #define osCharLowerW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[1].pCurrent)
483 
484 #if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
485   { "CharUpperW",              (SYSCALL)CharUpperW,              0 },
486 #else
487   { "CharUpperW",              (SYSCALL)0,                       0 },
488 #endif
489 
490 #define osCharUpperW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[2].pCurrent)
491 
492   { "CloseHandle",             (SYSCALL)CloseHandle,             0 },
493 
494 #define osCloseHandle ((BOOL(WINAPI*)(HANDLE))aSyscall[3].pCurrent)
495 
496 #if defined(SQLITE_WIN32_HAS_ANSI)
497   { "CreateFileA",             (SYSCALL)CreateFileA,             0 },
498 #else
499   { "CreateFileA",             (SYSCALL)0,                       0 },
500 #endif
501 
502 #define osCreateFileA ((HANDLE(WINAPI*)(LPCSTR,DWORD,DWORD, \
503         LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[4].pCurrent)
504 
505 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
506   { "CreateFileW",             (SYSCALL)CreateFileW,             0 },
507 #else
508   { "CreateFileW",             (SYSCALL)0,                       0 },
509 #endif
510 
511 #define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
512         LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)
513 
514 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_ANSI) && \
515         (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0) && \
516         SQLITE_WIN32_CREATEFILEMAPPINGA
517   { "CreateFileMappingA",      (SYSCALL)CreateFileMappingA,      0 },
518 #else
519   { "CreateFileMappingA",      (SYSCALL)0,                       0 },
520 #endif
521 
522 #define osCreateFileMappingA ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
523         DWORD,DWORD,DWORD,LPCSTR))aSyscall[6].pCurrent)
524 
525 #if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
526         (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0))
527   { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
528 #else
529   { "CreateFileMappingW",      (SYSCALL)0,                       0 },
530 #endif
531 
532 #define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
533         DWORD,DWORD,DWORD,LPCWSTR))aSyscall[7].pCurrent)
534 
535 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
536   { "CreateMutexW",            (SYSCALL)CreateMutexW,            0 },
537 #else
538   { "CreateMutexW",            (SYSCALL)0,                       0 },
539 #endif
540 
541 #define osCreateMutexW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,BOOL, \
542         LPCWSTR))aSyscall[8].pCurrent)
543 
544 #if defined(SQLITE_WIN32_HAS_ANSI)
545   { "DeleteFileA",             (SYSCALL)DeleteFileA,             0 },
546 #else
547   { "DeleteFileA",             (SYSCALL)0,                       0 },
548 #endif
549 
550 #define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[9].pCurrent)
551 
552 #if defined(SQLITE_WIN32_HAS_WIDE)
553   { "DeleteFileW",             (SYSCALL)DeleteFileW,             0 },
554 #else
555   { "DeleteFileW",             (SYSCALL)0,                       0 },
556 #endif
557 
558 #define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[10].pCurrent)
559 
560 #if SQLITE_OS_WINCE
561   { "FileTimeToLocalFileTime", (SYSCALL)FileTimeToLocalFileTime, 0 },
562 #else
563   { "FileTimeToLocalFileTime", (SYSCALL)0,                       0 },
564 #endif
565 
566 #define osFileTimeToLocalFileTime ((BOOL(WINAPI*)(CONST FILETIME*, \
567         LPFILETIME))aSyscall[11].pCurrent)
568 
569 #if SQLITE_OS_WINCE
570   { "FileTimeToSystemTime",    (SYSCALL)FileTimeToSystemTime,    0 },
571 #else
572   { "FileTimeToSystemTime",    (SYSCALL)0,                       0 },
573 #endif
574 
575 #define osFileTimeToSystemTime ((BOOL(WINAPI*)(CONST FILETIME*, \
576         LPSYSTEMTIME))aSyscall[12].pCurrent)
577 
578   { "FlushFileBuffers",        (SYSCALL)FlushFileBuffers,        0 },
579 
580 #define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[13].pCurrent)
581 
582 #if defined(SQLITE_WIN32_HAS_ANSI)
583   { "FormatMessageA",          (SYSCALL)FormatMessageA,          0 },
584 #else
585   { "FormatMessageA",          (SYSCALL)0,                       0 },
586 #endif
587 
588 #define osFormatMessageA ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPSTR, \
589         DWORD,va_list*))aSyscall[14].pCurrent)
590 
591 #if defined(SQLITE_WIN32_HAS_WIDE)
592   { "FormatMessageW",          (SYSCALL)FormatMessageW,          0 },
593 #else
594   { "FormatMessageW",          (SYSCALL)0,                       0 },
595 #endif
596 
597 #define osFormatMessageW ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPWSTR, \
598         DWORD,va_list*))aSyscall[15].pCurrent)
599 
600 #if !defined(SQLITE_OMIT_LOAD_EXTENSION)
601   { "FreeLibrary",             (SYSCALL)FreeLibrary,             0 },
602 #else
603   { "FreeLibrary",             (SYSCALL)0,                       0 },
604 #endif
605 
606 #define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[16].pCurrent)
607 
608   { "GetCurrentProcessId",     (SYSCALL)GetCurrentProcessId,     0 },
609 
610 #define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[17].pCurrent)
611 
612 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
613   { "GetDiskFreeSpaceA",       (SYSCALL)GetDiskFreeSpaceA,       0 },
614 #else
615   { "GetDiskFreeSpaceA",       (SYSCALL)0,                       0 },
616 #endif
617 
618 #define osGetDiskFreeSpaceA ((BOOL(WINAPI*)(LPCSTR,LPDWORD,LPDWORD,LPDWORD, \
619         LPDWORD))aSyscall[18].pCurrent)
620 
621 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
622   { "GetDiskFreeSpaceW",       (SYSCALL)GetDiskFreeSpaceW,       0 },
623 #else
624   { "GetDiskFreeSpaceW",       (SYSCALL)0,                       0 },
625 #endif
626 
627 #define osGetDiskFreeSpaceW ((BOOL(WINAPI*)(LPCWSTR,LPDWORD,LPDWORD,LPDWORD, \
628         LPDWORD))aSyscall[19].pCurrent)
629 
630 #if defined(SQLITE_WIN32_HAS_ANSI)
631   { "GetFileAttributesA",      (SYSCALL)GetFileAttributesA,      0 },
632 #else
633   { "GetFileAttributesA",      (SYSCALL)0,                       0 },
634 #endif
635 
636 #define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[20].pCurrent)
637 
638 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
639   { "GetFileAttributesW",      (SYSCALL)GetFileAttributesW,      0 },
640 #else
641   { "GetFileAttributesW",      (SYSCALL)0,                       0 },
642 #endif
643 
644 #define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[21].pCurrent)
645 
646 #if defined(SQLITE_WIN32_HAS_WIDE)
647   { "GetFileAttributesExW",    (SYSCALL)GetFileAttributesExW,    0 },
648 #else
649   { "GetFileAttributesExW",    (SYSCALL)0,                       0 },
650 #endif
651 
652 #define osGetFileAttributesExW ((BOOL(WINAPI*)(LPCWSTR,GET_FILEEX_INFO_LEVELS, \
653         LPVOID))aSyscall[22].pCurrent)
654 
655 #if !SQLITE_OS_WINRT
656   { "GetFileSize",             (SYSCALL)GetFileSize,             0 },
657 #else
658   { "GetFileSize",             (SYSCALL)0,                       0 },
659 #endif
660 
661 #define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[23].pCurrent)
662 
663 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
664   { "GetFullPathNameA",        (SYSCALL)GetFullPathNameA,        0 },
665 #else
666   { "GetFullPathNameA",        (SYSCALL)0,                       0 },
667 #endif
668 
669 #define osGetFullPathNameA ((DWORD(WINAPI*)(LPCSTR,DWORD,LPSTR, \
670         LPSTR*))aSyscall[24].pCurrent)
671 
672 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
673   { "GetFullPathNameW",        (SYSCALL)GetFullPathNameW,        0 },
674 #else
675   { "GetFullPathNameW",        (SYSCALL)0,                       0 },
676 #endif
677 
678 #define osGetFullPathNameW ((DWORD(WINAPI*)(LPCWSTR,DWORD,LPWSTR, \
679         LPWSTR*))aSyscall[25].pCurrent)
680 
681   { "GetLastError",            (SYSCALL)GetLastError,            0 },
682 
683 #define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[26].pCurrent)
684 
685 #if !defined(SQLITE_OMIT_LOAD_EXTENSION)
686 #if SQLITE_OS_WINCE
687   /* The GetProcAddressA() routine is only available on Windows CE. */
688   { "GetProcAddressA",         (SYSCALL)GetProcAddressA,         0 },
689 #else
690   /* All other Windows platforms expect GetProcAddress() to take
691   ** an ANSI string regardless of the _UNICODE setting */
692   { "GetProcAddressA",         (SYSCALL)GetProcAddress,          0 },
693 #endif
694 #else
695   { "GetProcAddressA",         (SYSCALL)0,                       0 },
696 #endif
697 
698 #define osGetProcAddressA ((FARPROC(WINAPI*)(HMODULE, \
699         LPCSTR))aSyscall[27].pCurrent)
700 
701 #if !SQLITE_OS_WINRT
702   { "GetSystemInfo",           (SYSCALL)GetSystemInfo,           0 },
703 #else
704   { "GetSystemInfo",           (SYSCALL)0,                       0 },
705 #endif
706 
707 #define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[28].pCurrent)
708 
709   { "GetSystemTime",           (SYSCALL)GetSystemTime,           0 },
710 
711 #define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[29].pCurrent)
712 
713 #if !SQLITE_OS_WINCE
714   { "GetSystemTimeAsFileTime", (SYSCALL)GetSystemTimeAsFileTime, 0 },
715 #else
716   { "GetSystemTimeAsFileTime", (SYSCALL)0,                       0 },
717 #endif
718 
719 #define osGetSystemTimeAsFileTime ((VOID(WINAPI*)( \
720         LPFILETIME))aSyscall[30].pCurrent)
721 
722 #if defined(SQLITE_WIN32_HAS_ANSI)
723   { "GetTempPathA",            (SYSCALL)GetTempPathA,            0 },
724 #else
725   { "GetTempPathA",            (SYSCALL)0,                       0 },
726 #endif
727 
728 #define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[31].pCurrent)
729 
730 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
731   { "GetTempPathW",            (SYSCALL)GetTempPathW,            0 },
732 #else
733   { "GetTempPathW",            (SYSCALL)0,                       0 },
734 #endif
735 
736 #define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[32].pCurrent)
737 
738 #if !SQLITE_OS_WINRT
739   { "GetTickCount",            (SYSCALL)GetTickCount,            0 },
740 #else
741   { "GetTickCount",            (SYSCALL)0,                       0 },
742 #endif
743 
744 #define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[33].pCurrent)
745 
746 #if defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_GETVERSIONEX
747   { "GetVersionExA",           (SYSCALL)GetVersionExA,           0 },
748 #else
749   { "GetVersionExA",           (SYSCALL)0,                       0 },
750 #endif
751 
752 #define osGetVersionExA ((BOOL(WINAPI*)( \
753         LPOSVERSIONINFOA))aSyscall[34].pCurrent)
754 
755 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
756         SQLITE_WIN32_GETVERSIONEX
757   { "GetVersionExW",           (SYSCALL)GetVersionExW,           0 },
758 #else
759   { "GetVersionExW",           (SYSCALL)0,                       0 },
760 #endif
761 
762 #define osGetVersionExW ((BOOL(WINAPI*)( \
763         LPOSVERSIONINFOW))aSyscall[35].pCurrent)
764 
765   { "HeapAlloc",               (SYSCALL)HeapAlloc,               0 },
766 
767 #define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
768         SIZE_T))aSyscall[36].pCurrent)
769 
770 #if !SQLITE_OS_WINRT
771   { "HeapCreate",              (SYSCALL)HeapCreate,              0 },
772 #else
773   { "HeapCreate",              (SYSCALL)0,                       0 },
774 #endif
775 
776 #define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
777         SIZE_T))aSyscall[37].pCurrent)
778 
779 #if !SQLITE_OS_WINRT
780   { "HeapDestroy",             (SYSCALL)HeapDestroy,             0 },
781 #else
782   { "HeapDestroy",             (SYSCALL)0,                       0 },
783 #endif
784 
785 #define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[38].pCurrent)
786 
787   { "HeapFree",                (SYSCALL)HeapFree,                0 },
788 
789 #define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[39].pCurrent)
790 
791   { "HeapReAlloc",             (SYSCALL)HeapReAlloc,             0 },
792 
793 #define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
794         SIZE_T))aSyscall[40].pCurrent)
795 
796   { "HeapSize",                (SYSCALL)HeapSize,                0 },
797 
798 #define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
799         LPCVOID))aSyscall[41].pCurrent)
800 
801 #if !SQLITE_OS_WINRT
802   { "HeapValidate",            (SYSCALL)HeapValidate,            0 },
803 #else
804   { "HeapValidate",            (SYSCALL)0,                       0 },
805 #endif
806 
807 #define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
808         LPCVOID))aSyscall[42].pCurrent)
809 
810 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
811   { "HeapCompact",             (SYSCALL)HeapCompact,             0 },
812 #else
813   { "HeapCompact",             (SYSCALL)0,                       0 },
814 #endif
815 
816 #define osHeapCompact ((UINT(WINAPI*)(HANDLE,DWORD))aSyscall[43].pCurrent)
817 
818 #if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
819   { "LoadLibraryA",            (SYSCALL)LoadLibraryA,            0 },
820 #else
821   { "LoadLibraryA",            (SYSCALL)0,                       0 },
822 #endif
823 
824 #define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[44].pCurrent)
825 
826 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
827         !defined(SQLITE_OMIT_LOAD_EXTENSION)
828   { "LoadLibraryW",            (SYSCALL)LoadLibraryW,            0 },
829 #else
830   { "LoadLibraryW",            (SYSCALL)0,                       0 },
831 #endif
832 
833 #define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[45].pCurrent)
834 
835 #if !SQLITE_OS_WINRT
836   { "LocalFree",               (SYSCALL)LocalFree,               0 },
837 #else
838   { "LocalFree",               (SYSCALL)0,                       0 },
839 #endif
840 
841 #define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[46].pCurrent)
842 
843 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
844   { "LockFile",                (SYSCALL)LockFile,                0 },
845 #else
846   { "LockFile",                (SYSCALL)0,                       0 },
847 #endif
848 
849 #ifndef osLockFile
850 #define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
851         DWORD))aSyscall[47].pCurrent)
852 #endif
853 
854 #if !SQLITE_OS_WINCE
855   { "LockFileEx",              (SYSCALL)LockFileEx,              0 },
856 #else
857   { "LockFileEx",              (SYSCALL)0,                       0 },
858 #endif
859 
860 #ifndef osLockFileEx
861 #define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
862         LPOVERLAPPED))aSyscall[48].pCurrent)
863 #endif
864 
865 #if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && \
866         (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0))
867   { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
868 #else
869   { "MapViewOfFile",           (SYSCALL)0,                       0 },
870 #endif
871 
872 #define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
873         SIZE_T))aSyscall[49].pCurrent)
874 
875   { "MultiByteToWideChar",     (SYSCALL)MultiByteToWideChar,     0 },
876 
877 #define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
878         int))aSyscall[50].pCurrent)
879 
880   { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },
881 
882 #define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
883         LARGE_INTEGER*))aSyscall[51].pCurrent)
884 
885   { "ReadFile",                (SYSCALL)ReadFile,                0 },
886 
887 #define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
888         LPOVERLAPPED))aSyscall[52].pCurrent)
889 
890   { "SetEndOfFile",            (SYSCALL)SetEndOfFile,            0 },
891 
892 #define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[53].pCurrent)
893 
894 #if !SQLITE_OS_WINRT
895   { "SetFilePointer",          (SYSCALL)SetFilePointer,          0 },
896 #else
897   { "SetFilePointer",          (SYSCALL)0,                       0 },
898 #endif
899 
900 #define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
901         DWORD))aSyscall[54].pCurrent)
902 
903 #if !SQLITE_OS_WINRT
904   { "Sleep",                   (SYSCALL)Sleep,                   0 },
905 #else
906   { "Sleep",                   (SYSCALL)0,                       0 },
907 #endif
908 
909 #define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[55].pCurrent)
910 
911   { "SystemTimeToFileTime",    (SYSCALL)SystemTimeToFileTime,    0 },
912 
913 #define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
914         LPFILETIME))aSyscall[56].pCurrent)
915 
916 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
917   { "UnlockFile",              (SYSCALL)UnlockFile,              0 },
918 #else
919   { "UnlockFile",              (SYSCALL)0,                       0 },
920 #endif
921 
922 #ifndef osUnlockFile
923 #define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
924         DWORD))aSyscall[57].pCurrent)
925 #endif
926 
927 #if !SQLITE_OS_WINCE
928   { "UnlockFileEx",            (SYSCALL)UnlockFileEx,            0 },
929 #else
930   { "UnlockFileEx",            (SYSCALL)0,                       0 },
931 #endif
932 
933 #define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
934         LPOVERLAPPED))aSyscall[58].pCurrent)
935 
936 #if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
937   { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
938 #else
939   { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
940 #endif
941 
942 #define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[59].pCurrent)
943 
944   { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },
945 
946 #define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
947         LPCSTR,LPBOOL))aSyscall[60].pCurrent)
948 
949   { "WriteFile",               (SYSCALL)WriteFile,               0 },
950 
951 #define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
952         LPOVERLAPPED))aSyscall[61].pCurrent)
953 
954 #if SQLITE_OS_WINRT
955   { "CreateEventExW",          (SYSCALL)CreateEventExW,          0 },
956 #else
957   { "CreateEventExW",          (SYSCALL)0,                       0 },
958 #endif
959 
960 #define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
961         DWORD,DWORD))aSyscall[62].pCurrent)
962 
963 #if !SQLITE_OS_WINRT
964   { "WaitForSingleObject",     (SYSCALL)WaitForSingleObject,     0 },
965 #else
966   { "WaitForSingleObject",     (SYSCALL)0,                       0 },
967 #endif
968 
969 #define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
970         DWORD))aSyscall[63].pCurrent)
971 
972 #if !SQLITE_OS_WINCE
973   { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
974 #else
975   { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
976 #endif
977 
978 #define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
979         BOOL))aSyscall[64].pCurrent)
980 
981 #if SQLITE_OS_WINRT
982   { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
983 #else
984   { "SetFilePointerEx",        (SYSCALL)0,                       0 },
985 #endif
986 
987 #define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
988         PLARGE_INTEGER,DWORD))aSyscall[65].pCurrent)
989 
990 #if SQLITE_OS_WINRT
991   { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
992 #else
993   { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
994 #endif
995 
996 #define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
997         FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[66].pCurrent)
998 
999 #if SQLITE_OS_WINRT && (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
1000   { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
1001 #else
1002   { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
1003 #endif
1004 
1005 #define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
1006         SIZE_T))aSyscall[67].pCurrent)
1007 
1008 #if SQLITE_OS_WINRT
1009   { "CreateFile2",             (SYSCALL)CreateFile2,             0 },
1010 #else
1011   { "CreateFile2",             (SYSCALL)0,                       0 },
1012 #endif
1013 
1014 #define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
1015         LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[68].pCurrent)
1016 
1017 #if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
1018   { "LoadPackagedLibrary",     (SYSCALL)LoadPackagedLibrary,     0 },
1019 #else
1020   { "LoadPackagedLibrary",     (SYSCALL)0,                       0 },
1021 #endif
1022 
1023 #define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
1024         DWORD))aSyscall[69].pCurrent)
1025 
1026 #if SQLITE_OS_WINRT
1027   { "GetTickCount64",          (SYSCALL)GetTickCount64,          0 },
1028 #else
1029   { "GetTickCount64",          (SYSCALL)0,                       0 },
1030 #endif
1031 
1032 #define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[70].pCurrent)
1033 
1034 #if SQLITE_OS_WINRT
1035   { "GetNativeSystemInfo",     (SYSCALL)GetNativeSystemInfo,     0 },
1036 #else
1037   { "GetNativeSystemInfo",     (SYSCALL)0,                       0 },
1038 #endif
1039 
1040 #define osGetNativeSystemInfo ((VOID(WINAPI*)( \
1041         LPSYSTEM_INFO))aSyscall[71].pCurrent)
1042 
1043 #if defined(SQLITE_WIN32_HAS_ANSI)
1044   { "OutputDebugStringA",      (SYSCALL)OutputDebugStringA,      0 },
1045 #else
1046   { "OutputDebugStringA",      (SYSCALL)0,                       0 },
1047 #endif
1048 
1049 #define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[72].pCurrent)
1050 
1051 #if defined(SQLITE_WIN32_HAS_WIDE)
1052   { "OutputDebugStringW",      (SYSCALL)OutputDebugStringW,      0 },
1053 #else
1054   { "OutputDebugStringW",      (SYSCALL)0,                       0 },
1055 #endif
1056 
1057 #define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[73].pCurrent)
1058 
1059   { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },
1060 
1061 #define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[74].pCurrent)
1062 
1063 #if SQLITE_OS_WINRT && (!defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0)
1064   { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
1065 #else
1066   { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
1067 #endif
1068 
1069 #define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
1070         LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[75].pCurrent)
1071 
1072 /*
1073 ** NOTE: On some sub-platforms, the InterlockedCompareExchange "function"
1074 **       is really just a macro that uses a compiler intrinsic (e.g. x64).
1075 **       So do not try to make this is into a redefinable interface.
1076 */
1077 #if defined(InterlockedCompareExchange)
1078   { "InterlockedCompareExchange", (SYSCALL)0,                    0 },
1079 
1080 #define osInterlockedCompareExchange InterlockedCompareExchange
1081 #else
1082   { "InterlockedCompareExchange", (SYSCALL)InterlockedCompareExchange, 0 },
1083 
1084 #define osInterlockedCompareExchange ((LONG(WINAPI*)(LONG \
1085         SQLITE_WIN32_VOLATILE*, LONG,LONG))aSyscall[76].pCurrent)
1086 #endif /* defined(InterlockedCompareExchange) */
1087 
1088 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
1089   { "UuidCreate",               (SYSCALL)UuidCreate,             0 },
1090 #else
1091   { "UuidCreate",               (SYSCALL)0,                      0 },
1092 #endif
1093 
1094 #define osUuidCreate ((RPC_STATUS(RPC_ENTRY*)(UUID*))aSyscall[77].pCurrent)
1095 
1096 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
1097   { "UuidCreateSequential",     (SYSCALL)UuidCreateSequential,   0 },
1098 #else
1099   { "UuidCreateSequential",     (SYSCALL)0,                      0 },
1100 #endif
1101 
1102 #define osUuidCreateSequential \
1103         ((RPC_STATUS(RPC_ENTRY*)(UUID*))aSyscall[78].pCurrent)
1104 
1105 #if !defined(SQLITE_NO_SYNC) && SQLITE_MAX_MMAP_SIZE>0
1106   { "FlushViewOfFile",          (SYSCALL)FlushViewOfFile,        0 },
1107 #else
1108   { "FlushViewOfFile",          (SYSCALL)0,                      0 },
1109 #endif
1110 
1111 #define osFlushViewOfFile \
1112         ((BOOL(WINAPI*)(LPCVOID,SIZE_T))aSyscall[79].pCurrent)
1113 
1114 }; /* End of the overrideable system calls */
1115 
1116 /*
1117 ** This is the xSetSystemCall() method of sqlite3_vfs for all of the
1118 ** "win32" VFSes.  Return SQLITE_OK opon successfully updating the
1119 ** system call pointer, or SQLITE_NOTFOUND if there is no configurable
1120 ** system call named zName.
1121 */
1122 static int winSetSystemCall(
1123   sqlite3_vfs *pNotUsed,        /* The VFS pointer.  Not used */
1124   const char *zName,            /* Name of system call to override */
1125   sqlite3_syscall_ptr pNewFunc  /* Pointer to new system call value */
1126 ){
1127   unsigned int i;
1128   int rc = SQLITE_NOTFOUND;
1129 
1130   UNUSED_PARAMETER(pNotUsed);
1131   if( zName==0 ){
1132     /* If no zName is given, restore all system calls to their default
1133     ** settings and return NULL
1134     */
1135     rc = SQLITE_OK;
1136     for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1137       if( aSyscall[i].pDefault ){
1138         aSyscall[i].pCurrent = aSyscall[i].pDefault;
1139       }
1140     }
1141   }else{
1142     /* If zName is specified, operate on only the one system call
1143     ** specified.
1144     */
1145     for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1146       if( strcmp(zName, aSyscall[i].zName)==0 ){
1147         if( aSyscall[i].pDefault==0 ){
1148           aSyscall[i].pDefault = aSyscall[i].pCurrent;
1149         }
1150         rc = SQLITE_OK;
1151         if( pNewFunc==0 ) pNewFunc = aSyscall[i].pDefault;
1152         aSyscall[i].pCurrent = pNewFunc;
1153         break;
1154       }
1155     }
1156   }
1157   return rc;
1158 }
1159 
1160 /*
1161 ** Return the value of a system call.  Return NULL if zName is not a
1162 ** recognized system call name.  NULL is also returned if the system call
1163 ** is currently undefined.
1164 */
1165 static sqlite3_syscall_ptr winGetSystemCall(
1166   sqlite3_vfs *pNotUsed,
1167   const char *zName
1168 ){
1169   unsigned int i;
1170 
1171   UNUSED_PARAMETER(pNotUsed);
1172   for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1173     if( strcmp(zName, aSyscall[i].zName)==0 ) return aSyscall[i].pCurrent;
1174   }
1175   return 0;
1176 }
1177 
1178 /*
1179 ** Return the name of the first system call after zName.  If zName==NULL
1180 ** then return the name of the first system call.  Return NULL if zName
1181 ** is the last system call or if zName is not the name of a valid
1182 ** system call.
1183 */
1184 static const char *winNextSystemCall(sqlite3_vfs *p, const char *zName){
1185   int i = -1;
1186 
1187   UNUSED_PARAMETER(p);
1188   if( zName ){
1189     for(i=0; i<ArraySize(aSyscall)-1; i++){
1190       if( strcmp(zName, aSyscall[i].zName)==0 ) break;
1191     }
1192   }
1193   for(i++; i<ArraySize(aSyscall); i++){
1194     if( aSyscall[i].pCurrent!=0 ) return aSyscall[i].zName;
1195   }
1196   return 0;
1197 }
1198 
1199 #ifdef SQLITE_WIN32_MALLOC
1200 /*
1201 ** If a Win32 native heap has been configured, this function will attempt to
1202 ** compact it.  Upon success, SQLITE_OK will be returned.  Upon failure, one
1203 ** of SQLITE_NOMEM, SQLITE_ERROR, or SQLITE_NOTFOUND will be returned.  The
1204 ** "pnLargest" argument, if non-zero, will be used to return the size of the
1205 ** largest committed free block in the heap, in bytes.
1206 */
1207 int sqlite3_win32_compact_heap(LPUINT pnLargest){
1208   int rc = SQLITE_OK;
1209   UINT nLargest = 0;
1210   HANDLE hHeap;
1211 
1212   winMemAssertMagic();
1213   hHeap = winMemGetHeap();
1214   assert( hHeap!=0 );
1215   assert( hHeap!=INVALID_HANDLE_VALUE );
1216 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1217   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1218 #endif
1219 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
1220   if( (nLargest=osHeapCompact(hHeap, SQLITE_WIN32_HEAP_FLAGS))==0 ){
1221     DWORD lastErrno = osGetLastError();
1222     if( lastErrno==NO_ERROR ){
1223       sqlite3_log(SQLITE_NOMEM, "failed to HeapCompact (no space), heap=%p",
1224                   (void*)hHeap);
1225       rc = SQLITE_NOMEM_BKPT;
1226     }else{
1227       sqlite3_log(SQLITE_ERROR, "failed to HeapCompact (%lu), heap=%p",
1228                   osGetLastError(), (void*)hHeap);
1229       rc = SQLITE_ERROR;
1230     }
1231   }
1232 #else
1233   sqlite3_log(SQLITE_NOTFOUND, "failed to HeapCompact, heap=%p",
1234               (void*)hHeap);
1235   rc = SQLITE_NOTFOUND;
1236 #endif
1237   if( pnLargest ) *pnLargest = nLargest;
1238   return rc;
1239 }
1240 
1241 /*
1242 ** If a Win32 native heap has been configured, this function will attempt to
1243 ** destroy and recreate it.  If the Win32 native heap is not isolated and/or
1244 ** the sqlite3_memory_used() function does not return zero, SQLITE_BUSY will
1245 ** be returned and no changes will be made to the Win32 native heap.
1246 */
1247 int sqlite3_win32_reset_heap(){
1248   int rc;
1249   MUTEX_LOGIC( sqlite3_mutex *pMaster; ) /* The main static mutex */
1250   MUTEX_LOGIC( sqlite3_mutex *pMem; )    /* The memsys static mutex */
1251   MUTEX_LOGIC( pMaster = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER); )
1252   MUTEX_LOGIC( pMem = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM); )
1253   sqlite3_mutex_enter(pMaster);
1254   sqlite3_mutex_enter(pMem);
1255   winMemAssertMagic();
1256   if( winMemGetHeap()!=NULL && winMemGetOwned() && sqlite3_memory_used()==0 ){
1257     /*
1258     ** At this point, there should be no outstanding memory allocations on
1259     ** the heap.  Also, since both the master and memsys locks are currently
1260     ** being held by us, no other function (i.e. from another thread) should
1261     ** be able to even access the heap.  Attempt to destroy and recreate our
1262     ** isolated Win32 native heap now.
1263     */
1264     assert( winMemGetHeap()!=NULL );
1265     assert( winMemGetOwned() );
1266     assert( sqlite3_memory_used()==0 );
1267     winMemShutdown(winMemGetDataPtr());
1268     assert( winMemGetHeap()==NULL );
1269     assert( !winMemGetOwned() );
1270     assert( sqlite3_memory_used()==0 );
1271     rc = winMemInit(winMemGetDataPtr());
1272     assert( rc!=SQLITE_OK || winMemGetHeap()!=NULL );
1273     assert( rc!=SQLITE_OK || winMemGetOwned() );
1274     assert( rc!=SQLITE_OK || sqlite3_memory_used()==0 );
1275   }else{
1276     /*
1277     ** The Win32 native heap cannot be modified because it may be in use.
1278     */
1279     rc = SQLITE_BUSY;
1280   }
1281   sqlite3_mutex_leave(pMem);
1282   sqlite3_mutex_leave(pMaster);
1283   return rc;
1284 }
1285 #endif /* SQLITE_WIN32_MALLOC */
1286 
1287 /*
1288 ** This function outputs the specified (ANSI) string to the Win32 debugger
1289 ** (if available).
1290 */
1291 
1292 void sqlite3_win32_write_debug(const char *zBuf, int nBuf){
1293   char zDbgBuf[SQLITE_WIN32_DBG_BUF_SIZE];
1294   int nMin = MIN(nBuf, (SQLITE_WIN32_DBG_BUF_SIZE - 1)); /* may be negative. */
1295   if( nMin<-1 ) nMin = -1; /* all negative values become -1. */
1296   assert( nMin==-1 || nMin==0 || nMin<SQLITE_WIN32_DBG_BUF_SIZE );
1297 #if defined(SQLITE_WIN32_HAS_ANSI)
1298   if( nMin>0 ){
1299     memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1300     memcpy(zDbgBuf, zBuf, nMin);
1301     osOutputDebugStringA(zDbgBuf);
1302   }else{
1303     osOutputDebugStringA(zBuf);
1304   }
1305 #elif defined(SQLITE_WIN32_HAS_WIDE)
1306   memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1307   if ( osMultiByteToWideChar(
1308           osAreFileApisANSI() ? CP_ACP : CP_OEMCP, 0, zBuf,
1309           nMin, (LPWSTR)zDbgBuf, SQLITE_WIN32_DBG_BUF_SIZE/sizeof(WCHAR))<=0 ){
1310     return;
1311   }
1312   osOutputDebugStringW((LPCWSTR)zDbgBuf);
1313 #else
1314   if( nMin>0 ){
1315     memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1316     memcpy(zDbgBuf, zBuf, nMin);
1317     fprintf(stderr, "%s", zDbgBuf);
1318   }else{
1319     fprintf(stderr, "%s", zBuf);
1320   }
1321 #endif
1322 }
1323 
1324 /*
1325 ** The following routine suspends the current thread for at least ms
1326 ** milliseconds.  This is equivalent to the Win32 Sleep() interface.
1327 */
1328 #if SQLITE_OS_WINRT
1329 static HANDLE sleepObj = NULL;
1330 #endif
1331 
1332 void sqlite3_win32_sleep(DWORD milliseconds){
1333 #if SQLITE_OS_WINRT
1334   if ( sleepObj==NULL ){
1335     sleepObj = osCreateEventExW(NULL, NULL, CREATE_EVENT_MANUAL_RESET,
1336                                 SYNCHRONIZE);
1337   }
1338   assert( sleepObj!=NULL );
1339   osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
1340 #else
1341   osSleep(milliseconds);
1342 #endif
1343 }
1344 
1345 #if SQLITE_MAX_WORKER_THREADS>0 && !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
1346         SQLITE_THREADSAFE>0
1347 DWORD sqlite3Win32Wait(HANDLE hObject){
1348   DWORD rc;
1349   while( (rc = osWaitForSingleObjectEx(hObject, INFINITE,
1350                                        TRUE))==WAIT_IO_COMPLETION ){}
1351   return rc;
1352 }
1353 #endif
1354 
1355 /*
1356 ** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
1357 ** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
1358 **
1359 ** Here is an interesting observation:  Win95, Win98, and WinME lack
1360 ** the LockFileEx() API.  But we can still statically link against that
1361 ** API as long as we don't call it when running Win95/98/ME.  A call to
1362 ** this routine is used to determine if the host is Win95/98/ME or
1363 ** WinNT/2K/XP so that we will know whether or not we can safely call
1364 ** the LockFileEx() API.
1365 */
1366 
1367 #if !SQLITE_WIN32_GETVERSIONEX
1368 # define osIsNT()  (1)
1369 #elif SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
1370 # define osIsNT()  (1)
1371 #elif !defined(SQLITE_WIN32_HAS_WIDE)
1372 # define osIsNT()  (0)
1373 #else
1374 # define osIsNT()  ((sqlite3_os_type==2) || sqlite3_win32_is_nt())
1375 #endif
1376 
1377 /*
1378 ** This function determines if the machine is running a version of Windows
1379 ** based on the NT kernel.
1380 */
1381 int sqlite3_win32_is_nt(void){
1382 #if SQLITE_OS_WINRT
1383   /*
1384   ** NOTE: The WinRT sub-platform is always assumed to be based on the NT
1385   **       kernel.
1386   */
1387   return 1;
1388 #elif SQLITE_WIN32_GETVERSIONEX
1389   if( osInterlockedCompareExchange(&sqlite3_os_type, 0, 0)==0 ){
1390 #if defined(SQLITE_WIN32_HAS_ANSI)
1391     OSVERSIONINFOA sInfo;
1392     sInfo.dwOSVersionInfoSize = sizeof(sInfo);
1393     osGetVersionExA(&sInfo);
1394     osInterlockedCompareExchange(&sqlite3_os_type,
1395         (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1, 0);
1396 #elif defined(SQLITE_WIN32_HAS_WIDE)
1397     OSVERSIONINFOW sInfo;
1398     sInfo.dwOSVersionInfoSize = sizeof(sInfo);
1399     osGetVersionExW(&sInfo);
1400     osInterlockedCompareExchange(&sqlite3_os_type,
1401         (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1, 0);
1402 #endif
1403   }
1404   return osInterlockedCompareExchange(&sqlite3_os_type, 2, 2)==2;
1405 #elif SQLITE_TEST
1406   return osInterlockedCompareExchange(&sqlite3_os_type, 2, 2)==2;
1407 #else
1408   /*
1409   ** NOTE: All sub-platforms where the GetVersionEx[AW] functions are
1410   **       deprecated are always assumed to be based on the NT kernel.
1411   */
1412   return 1;
1413 #endif
1414 }
1415 
1416 #ifdef SQLITE_WIN32_MALLOC
1417 /*
1418 ** Allocate nBytes of memory.
1419 */
1420 static void *winMemMalloc(int nBytes){
1421   HANDLE hHeap;
1422   void *p;
1423 
1424   winMemAssertMagic();
1425   hHeap = winMemGetHeap();
1426   assert( hHeap!=0 );
1427   assert( hHeap!=INVALID_HANDLE_VALUE );
1428 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1429   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1430 #endif
1431   assert( nBytes>=0 );
1432   p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
1433   if( !p ){
1434     sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%lu), heap=%p",
1435                 nBytes, osGetLastError(), (void*)hHeap);
1436   }
1437   return p;
1438 }
1439 
1440 /*
1441 ** Free memory.
1442 */
1443 static void winMemFree(void *pPrior){
1444   HANDLE hHeap;
1445 
1446   winMemAssertMagic();
1447   hHeap = winMemGetHeap();
1448   assert( hHeap!=0 );
1449   assert( hHeap!=INVALID_HANDLE_VALUE );
1450 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1451   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
1452 #endif
1453   if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
1454   if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
1455     sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%lu), heap=%p",
1456                 pPrior, osGetLastError(), (void*)hHeap);
1457   }
1458 }
1459 
1460 /*
1461 ** Change the size of an existing memory allocation
1462 */
1463 static void *winMemRealloc(void *pPrior, int nBytes){
1464   HANDLE hHeap;
1465   void *p;
1466 
1467   winMemAssertMagic();
1468   hHeap = winMemGetHeap();
1469   assert( hHeap!=0 );
1470   assert( hHeap!=INVALID_HANDLE_VALUE );
1471 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1472   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
1473 #endif
1474   assert( nBytes>=0 );
1475   if( !pPrior ){
1476     p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
1477   }else{
1478     p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
1479   }
1480   if( !p ){
1481     sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%lu), heap=%p",
1482                 pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
1483                 (void*)hHeap);
1484   }
1485   return p;
1486 }
1487 
1488 /*
1489 ** Return the size of an outstanding allocation, in bytes.
1490 */
1491 static int winMemSize(void *p){
1492   HANDLE hHeap;
1493   SIZE_T n;
1494 
1495   winMemAssertMagic();
1496   hHeap = winMemGetHeap();
1497   assert( hHeap!=0 );
1498   assert( hHeap!=INVALID_HANDLE_VALUE );
1499 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1500   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, p) );
1501 #endif
1502   if( !p ) return 0;
1503   n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
1504   if( n==(SIZE_T)-1 ){
1505     sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%lu), heap=%p",
1506                 p, osGetLastError(), (void*)hHeap);
1507     return 0;
1508   }
1509   return (int)n;
1510 }
1511 
1512 /*
1513 ** Round up a request size to the next valid allocation size.
1514 */
1515 static int winMemRoundup(int n){
1516   return n;
1517 }
1518 
1519 /*
1520 ** Initialize this module.
1521 */
1522 static int winMemInit(void *pAppData){
1523   winMemData *pWinMemData = (winMemData *)pAppData;
1524 
1525   if( !pWinMemData ) return SQLITE_ERROR;
1526   assert( pWinMemData->magic1==WINMEM_MAGIC1 );
1527   assert( pWinMemData->magic2==WINMEM_MAGIC2 );
1528 
1529 #if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
1530   if( !pWinMemData->hHeap ){
1531     DWORD dwInitialSize = SQLITE_WIN32_HEAP_INIT_SIZE;
1532     DWORD dwMaximumSize = (DWORD)sqlite3GlobalConfig.nHeap;
1533     if( dwMaximumSize==0 ){
1534       dwMaximumSize = SQLITE_WIN32_HEAP_MAX_SIZE;
1535     }else if( dwInitialSize>dwMaximumSize ){
1536       dwInitialSize = dwMaximumSize;
1537     }
1538     pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
1539                                       dwInitialSize, dwMaximumSize);
1540     if( !pWinMemData->hHeap ){
1541       sqlite3_log(SQLITE_NOMEM,
1542           "failed to HeapCreate (%lu), flags=%u, initSize=%lu, maxSize=%lu",
1543           osGetLastError(), SQLITE_WIN32_HEAP_FLAGS, dwInitialSize,
1544           dwMaximumSize);
1545       return SQLITE_NOMEM_BKPT;
1546     }
1547     pWinMemData->bOwned = TRUE;
1548     assert( pWinMemData->bOwned );
1549   }
1550 #else
1551   pWinMemData->hHeap = osGetProcessHeap();
1552   if( !pWinMemData->hHeap ){
1553     sqlite3_log(SQLITE_NOMEM,
1554         "failed to GetProcessHeap (%lu)", osGetLastError());
1555     return SQLITE_NOMEM_BKPT;
1556   }
1557   pWinMemData->bOwned = FALSE;
1558   assert( !pWinMemData->bOwned );
1559 #endif
1560   assert( pWinMemData->hHeap!=0 );
1561   assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
1562 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1563   assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1564 #endif
1565   return SQLITE_OK;
1566 }
1567 
1568 /*
1569 ** Deinitialize this module.
1570 */
1571 static void winMemShutdown(void *pAppData){
1572   winMemData *pWinMemData = (winMemData *)pAppData;
1573 
1574   if( !pWinMemData ) return;
1575   assert( pWinMemData->magic1==WINMEM_MAGIC1 );
1576   assert( pWinMemData->magic2==WINMEM_MAGIC2 );
1577 
1578   if( pWinMemData->hHeap ){
1579     assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
1580 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1581     assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1582 #endif
1583     if( pWinMemData->bOwned ){
1584       if( !osHeapDestroy(pWinMemData->hHeap) ){
1585         sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%lu), heap=%p",
1586                     osGetLastError(), (void*)pWinMemData->hHeap);
1587       }
1588       pWinMemData->bOwned = FALSE;
1589     }
1590     pWinMemData->hHeap = NULL;
1591   }
1592 }
1593 
1594 /*
1595 ** Populate the low-level memory allocation function pointers in
1596 ** sqlite3GlobalConfig.m with pointers to the routines in this file. The
1597 ** arguments specify the block of memory to manage.
1598 **
1599 ** This routine is only called by sqlite3_config(), and therefore
1600 ** is not required to be threadsafe (it is not).
1601 */
1602 const sqlite3_mem_methods *sqlite3MemGetWin32(void){
1603   static const sqlite3_mem_methods winMemMethods = {
1604     winMemMalloc,
1605     winMemFree,
1606     winMemRealloc,
1607     winMemSize,
1608     winMemRoundup,
1609     winMemInit,
1610     winMemShutdown,
1611     &win_mem_data
1612   };
1613   return &winMemMethods;
1614 }
1615 
1616 void sqlite3MemSetDefault(void){
1617   sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetWin32());
1618 }
1619 #endif /* SQLITE_WIN32_MALLOC */
1620 
1621 /*
1622 ** Convert a UTF-8 string to Microsoft Unicode (UTF-16?).
1623 **
1624 ** Space to hold the returned string is obtained from malloc.
1625 */
1626 static LPWSTR winUtf8ToUnicode(const char *zFilename){
1627   int nChar;
1628   LPWSTR zWideFilename;
1629 
1630   nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
1631   if( nChar==0 ){
1632     return 0;
1633   }
1634   zWideFilename = sqlite3MallocZero( nChar*sizeof(zWideFilename[0]) );
1635   if( zWideFilename==0 ){
1636     return 0;
1637   }
1638   nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename,
1639                                 nChar);
1640   if( nChar==0 ){
1641     sqlite3_free(zWideFilename);
1642     zWideFilename = 0;
1643   }
1644   return zWideFilename;
1645 }
1646 
1647 /*
1648 ** Convert Microsoft Unicode to UTF-8.  Space to hold the returned string is
1649 ** obtained from sqlite3_malloc().
1650 */
1651 static char *winUnicodeToUtf8(LPCWSTR zWideFilename){
1652   int nByte;
1653   char *zFilename;
1654 
1655   nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
1656   if( nByte == 0 ){
1657     return 0;
1658   }
1659   zFilename = sqlite3MallocZero( nByte );
1660   if( zFilename==0 ){
1661     return 0;
1662   }
1663   nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
1664                                 0, 0);
1665   if( nByte == 0 ){
1666     sqlite3_free(zFilename);
1667     zFilename = 0;
1668   }
1669   return zFilename;
1670 }
1671 
1672 /*
1673 ** Convert an ANSI string to Microsoft Unicode, based on the
1674 ** current codepage settings for file apis.
1675 **
1676 ** Space to hold the returned string is obtained
1677 ** from sqlite3_malloc.
1678 */
1679 static LPWSTR winMbcsToUnicode(const char *zFilename){
1680   int nByte;
1681   LPWSTR zMbcsFilename;
1682   int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
1683 
1684   nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, NULL,
1685                                 0)*sizeof(WCHAR);
1686   if( nByte==0 ){
1687     return 0;
1688   }
1689   zMbcsFilename = sqlite3MallocZero( nByte*sizeof(zMbcsFilename[0]) );
1690   if( zMbcsFilename==0 ){
1691     return 0;
1692   }
1693   nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename,
1694                                 nByte);
1695   if( nByte==0 ){
1696     sqlite3_free(zMbcsFilename);
1697     zMbcsFilename = 0;
1698   }
1699   return zMbcsFilename;
1700 }
1701 
1702 /*
1703 ** Convert Microsoft Unicode to multi-byte character string, based on the
1704 ** user's ANSI codepage.
1705 **
1706 ** Space to hold the returned string is obtained from
1707 ** sqlite3_malloc().
1708 */
1709 static char *winUnicodeToMbcs(LPCWSTR zWideFilename){
1710   int nByte;
1711   char *zFilename;
1712   int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
1713 
1714   nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
1715   if( nByte == 0 ){
1716     return 0;
1717   }
1718   zFilename = sqlite3MallocZero( nByte );
1719   if( zFilename==0 ){
1720     return 0;
1721   }
1722   nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename,
1723                                 nByte, 0, 0);
1724   if( nByte == 0 ){
1725     sqlite3_free(zFilename);
1726     zFilename = 0;
1727   }
1728   return zFilename;
1729 }
1730 
1731 /*
1732 ** Convert multibyte character string to UTF-8.  Space to hold the
1733 ** returned string is obtained from sqlite3_malloc().
1734 */
1735 char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){
1736   char *zFilenameUtf8;
1737   LPWSTR zTmpWide;
1738 
1739   zTmpWide = winMbcsToUnicode(zFilename);
1740   if( zTmpWide==0 ){
1741     return 0;
1742   }
1743   zFilenameUtf8 = winUnicodeToUtf8(zTmpWide);
1744   sqlite3_free(zTmpWide);
1745   return zFilenameUtf8;
1746 }
1747 
1748 /*
1749 ** Convert UTF-8 to multibyte character string.  Space to hold the
1750 ** returned string is obtained from sqlite3_malloc().
1751 */
1752 char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){
1753   char *zFilenameMbcs;
1754   LPWSTR zTmpWide;
1755 
1756   zTmpWide = winUtf8ToUnicode(zFilename);
1757   if( zTmpWide==0 ){
1758     return 0;
1759   }
1760   zFilenameMbcs = winUnicodeToMbcs(zTmpWide);
1761   sqlite3_free(zTmpWide);
1762   return zFilenameMbcs;
1763 }
1764 
1765 /*
1766 ** This function sets the data directory or the temporary directory based on
1767 ** the provided arguments.  The type argument must be 1 in order to set the
1768 ** data directory or 2 in order to set the temporary directory.  The zValue
1769 ** argument is the name of the directory to use.  The return value will be
1770 ** SQLITE_OK if successful.
1771 */
1772 int sqlite3_win32_set_directory(DWORD type, LPCWSTR zValue){
1773   char **ppDirectory = 0;
1774 #ifndef SQLITE_OMIT_AUTOINIT
1775   int rc = sqlite3_initialize();
1776   if( rc ) return rc;
1777 #endif
1778   if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
1779     ppDirectory = &sqlite3_data_directory;
1780   }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
1781     ppDirectory = &sqlite3_temp_directory;
1782   }
1783   assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
1784           || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
1785   );
1786   assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
1787   if( ppDirectory ){
1788     char *zValueUtf8 = 0;
1789     if( zValue && zValue[0] ){
1790       zValueUtf8 = winUnicodeToUtf8(zValue);
1791       if ( zValueUtf8==0 ){
1792         return SQLITE_NOMEM_BKPT;
1793       }
1794     }
1795     sqlite3_free(*ppDirectory);
1796     *ppDirectory = zValueUtf8;
1797     return SQLITE_OK;
1798   }
1799   return SQLITE_ERROR;
1800 }
1801 
1802 /*
1803 ** The return value of winGetLastErrorMsg
1804 ** is zero if the error message fits in the buffer, or non-zero
1805 ** otherwise (if the message was truncated).
1806 */
1807 static int winGetLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
1808   /* FormatMessage returns 0 on failure.  Otherwise it
1809   ** returns the number of TCHARs written to the output
1810   ** buffer, excluding the terminating null char.
1811   */
1812   DWORD dwLen = 0;
1813   char *zOut = 0;
1814 
1815   if( osIsNT() ){
1816 #if SQLITE_OS_WINRT
1817     WCHAR zTempWide[SQLITE_WIN32_MAX_ERRMSG_CHARS+1];
1818     dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
1819                              FORMAT_MESSAGE_IGNORE_INSERTS,
1820                              NULL,
1821                              lastErrno,
1822                              0,
1823                              zTempWide,
1824                              SQLITE_WIN32_MAX_ERRMSG_CHARS,
1825                              0);
1826 #else
1827     LPWSTR zTempWide = NULL;
1828     dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
1829                              FORMAT_MESSAGE_FROM_SYSTEM |
1830                              FORMAT_MESSAGE_IGNORE_INSERTS,
1831                              NULL,
1832                              lastErrno,
1833                              0,
1834                              (LPWSTR) &zTempWide,
1835                              0,
1836                              0);
1837 #endif
1838     if( dwLen > 0 ){
1839       /* allocate a buffer and convert to UTF8 */
1840       sqlite3BeginBenignMalloc();
1841       zOut = winUnicodeToUtf8(zTempWide);
1842       sqlite3EndBenignMalloc();
1843 #if !SQLITE_OS_WINRT
1844       /* free the system buffer allocated by FormatMessage */
1845       osLocalFree(zTempWide);
1846 #endif
1847     }
1848   }
1849 #ifdef SQLITE_WIN32_HAS_ANSI
1850   else{
1851     char *zTemp = NULL;
1852     dwLen = osFormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
1853                              FORMAT_MESSAGE_FROM_SYSTEM |
1854                              FORMAT_MESSAGE_IGNORE_INSERTS,
1855                              NULL,
1856                              lastErrno,
1857                              0,
1858                              (LPSTR) &zTemp,
1859                              0,
1860                              0);
1861     if( dwLen > 0 ){
1862       /* allocate a buffer and convert to UTF8 */
1863       sqlite3BeginBenignMalloc();
1864       zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
1865       sqlite3EndBenignMalloc();
1866       /* free the system buffer allocated by FormatMessage */
1867       osLocalFree(zTemp);
1868     }
1869   }
1870 #endif
1871   if( 0 == dwLen ){
1872     sqlite3_snprintf(nBuf, zBuf, "OsError 0x%lx (%lu)", lastErrno, lastErrno);
1873   }else{
1874     /* copy a maximum of nBuf chars to output buffer */
1875     sqlite3_snprintf(nBuf, zBuf, "%s", zOut);
1876     /* free the UTF8 buffer */
1877     sqlite3_free(zOut);
1878   }
1879   return 0;
1880 }
1881 
1882 /*
1883 **
1884 ** This function - winLogErrorAtLine() - is only ever called via the macro
1885 ** winLogError().
1886 **
1887 ** This routine is invoked after an error occurs in an OS function.
1888 ** It logs a message using sqlite3_log() containing the current value of
1889 ** error code and, if possible, the human-readable equivalent from
1890 ** FormatMessage.
1891 **
1892 ** The first argument passed to the macro should be the error code that
1893 ** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN).
1894 ** The two subsequent arguments should be the name of the OS function that
1895 ** failed and the associated file-system path, if any.
1896 */
1897 #define winLogError(a,b,c,d)   winLogErrorAtLine(a,b,c,d,__LINE__)
1898 static int winLogErrorAtLine(
1899   int errcode,                    /* SQLite error code */
1900   DWORD lastErrno,                /* Win32 last error */
1901   const char *zFunc,              /* Name of OS function that failed */
1902   const char *zPath,              /* File path associated with error */
1903   int iLine                       /* Source line number where error occurred */
1904 ){
1905   char zMsg[500];                 /* Human readable error text */
1906   int i;                          /* Loop counter */
1907 
1908   zMsg[0] = 0;
1909   winGetLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
1910   assert( errcode!=SQLITE_OK );
1911   if( zPath==0 ) zPath = "";
1912   for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
1913   zMsg[i] = 0;
1914   sqlite3_log(errcode,
1915       "os_win.c:%d: (%lu) %s(%s) - %s",
1916       iLine, lastErrno, zFunc, zPath, zMsg
1917   );
1918 
1919   return errcode;
1920 }
1921 
1922 /*
1923 ** The number of times that a ReadFile(), WriteFile(), and DeleteFile()
1924 ** will be retried following a locking error - probably caused by
1925 ** antivirus software.  Also the initial delay before the first retry.
1926 ** The delay increases linearly with each retry.
1927 */
1928 #ifndef SQLITE_WIN32_IOERR_RETRY
1929 # define SQLITE_WIN32_IOERR_RETRY 10
1930 #endif
1931 #ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
1932 # define SQLITE_WIN32_IOERR_RETRY_DELAY 25
1933 #endif
1934 static int winIoerrRetry = SQLITE_WIN32_IOERR_RETRY;
1935 static int winIoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;
1936 
1937 /*
1938 ** The "winIoerrCanRetry1" macro is used to determine if a particular I/O
1939 ** error code obtained via GetLastError() is eligible to be retried.  It
1940 ** must accept the error code DWORD as its only argument and should return
1941 ** non-zero if the error code is transient in nature and the operation
1942 ** responsible for generating the original error might succeed upon being
1943 ** retried.  The argument to this macro should be a variable.
1944 **
1945 ** Additionally, a macro named "winIoerrCanRetry2" may be defined.  If it
1946 ** is defined, it will be consulted only when the macro "winIoerrCanRetry1"
1947 ** returns zero.  The "winIoerrCanRetry2" macro is completely optional and
1948 ** may be used to include additional error codes in the set that should
1949 ** result in the failing I/O operation being retried by the caller.  If
1950 ** defined, the "winIoerrCanRetry2" macro must exhibit external semantics
1951 ** identical to those of the "winIoerrCanRetry1" macro.
1952 */
1953 #if !defined(winIoerrCanRetry1)
1954 #define winIoerrCanRetry1(a) (((a)==ERROR_ACCESS_DENIED)        || \
1955                               ((a)==ERROR_SHARING_VIOLATION)    || \
1956                               ((a)==ERROR_LOCK_VIOLATION)       || \
1957                               ((a)==ERROR_DEV_NOT_EXIST)        || \
1958                               ((a)==ERROR_NETNAME_DELETED)      || \
1959                               ((a)==ERROR_SEM_TIMEOUT)          || \
1960                               ((a)==ERROR_NETWORK_UNREACHABLE))
1961 #endif
1962 
1963 /*
1964 ** If a ReadFile() or WriteFile() error occurs, invoke this routine
1965 ** to see if it should be retried.  Return TRUE to retry.  Return FALSE
1966 ** to give up with an error.
1967 */
1968 static int winRetryIoerr(int *pnRetry, DWORD *pError){
1969   DWORD e = osGetLastError();
1970   if( *pnRetry>=winIoerrRetry ){
1971     if( pError ){
1972       *pError = e;
1973     }
1974     return 0;
1975   }
1976   if( winIoerrCanRetry1(e) ){
1977     sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
1978     ++*pnRetry;
1979     return 1;
1980   }
1981 #if defined(winIoerrCanRetry2)
1982   else if( winIoerrCanRetry2(e) ){
1983     sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
1984     ++*pnRetry;
1985     return 1;
1986   }
1987 #endif
1988   if( pError ){
1989     *pError = e;
1990   }
1991   return 0;
1992 }
1993 
1994 /*
1995 ** Log a I/O error retry episode.
1996 */
1997 static void winLogIoerr(int nRetry, int lineno){
1998   if( nRetry ){
1999     sqlite3_log(SQLITE_NOTICE,
2000       "delayed %dms for lock/sharing conflict at line %d",
2001       winIoerrRetryDelay*nRetry*(nRetry+1)/2, lineno
2002     );
2003   }
2004 }
2005 
2006 #if SQLITE_OS_WINCE
2007 /*************************************************************************
2008 ** This section contains code for WinCE only.
2009 */
2010 #if !defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API
2011 /*
2012 ** The MSVC CRT on Windows CE may not have a localtime() function.  So
2013 ** create a substitute.
2014 */
2015 #include <time.h>
2016 struct tm *__cdecl localtime(const time_t *t)
2017 {
2018   static struct tm y;
2019   FILETIME uTm, lTm;
2020   SYSTEMTIME pTm;
2021   sqlite3_int64 t64;
2022   t64 = *t;
2023   t64 = (t64 + 11644473600)*10000000;
2024   uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
2025   uTm.dwHighDateTime= (DWORD)(t64 >> 32);
2026   osFileTimeToLocalFileTime(&uTm,&lTm);
2027   osFileTimeToSystemTime(&lTm,&pTm);
2028   y.tm_year = pTm.wYear - 1900;
2029   y.tm_mon = pTm.wMonth - 1;
2030   y.tm_wday = pTm.wDayOfWeek;
2031   y.tm_mday = pTm.wDay;
2032   y.tm_hour = pTm.wHour;
2033   y.tm_min = pTm.wMinute;
2034   y.tm_sec = pTm.wSecond;
2035   return &y;
2036 }
2037 #endif
2038 
2039 #define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
2040 
2041 /*
2042 ** Acquire a lock on the handle h
2043 */
2044 static void winceMutexAcquire(HANDLE h){
2045    DWORD dwErr;
2046    do {
2047      dwErr = osWaitForSingleObject(h, INFINITE);
2048    } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
2049 }
2050 /*
2051 ** Release a lock acquired by winceMutexAcquire()
2052 */
2053 #define winceMutexRelease(h) ReleaseMutex(h)
2054 
2055 /*
2056 ** Create the mutex and shared memory used for locking in the file
2057 ** descriptor pFile
2058 */
2059 static int winceCreateLock(const char *zFilename, winFile *pFile){
2060   LPWSTR zTok;
2061   LPWSTR zName;
2062   DWORD lastErrno;
2063   BOOL bLogged = FALSE;
2064   BOOL bInit = TRUE;
2065 
2066   zName = winUtf8ToUnicode(zFilename);
2067   if( zName==0 ){
2068     /* out of memory */
2069     return SQLITE_IOERR_NOMEM_BKPT;
2070   }
2071 
2072   /* Initialize the local lockdata */
2073   memset(&pFile->local, 0, sizeof(pFile->local));
2074 
2075   /* Replace the backslashes from the filename and lowercase it
2076   ** to derive a mutex name. */
2077   zTok = osCharLowerW(zName);
2078   for (;*zTok;zTok++){
2079     if (*zTok == '\\') *zTok = '_';
2080   }
2081 
2082   /* Create/open the named mutex */
2083   pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
2084   if (!pFile->hMutex){
2085     pFile->lastErrno = osGetLastError();
2086     sqlite3_free(zName);
2087     return winLogError(SQLITE_IOERR, pFile->lastErrno,
2088                        "winceCreateLock1", zFilename);
2089   }
2090 
2091   /* Acquire the mutex before continuing */
2092   winceMutexAcquire(pFile->hMutex);
2093 
2094   /* Since the names of named mutexes, semaphores, file mappings etc are
2095   ** case-sensitive, take advantage of that by uppercasing the mutex name
2096   ** and using that as the shared filemapping name.
2097   */
2098   osCharUpperW(zName);
2099   pFile->hShared = osCreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
2100                                         PAGE_READWRITE, 0, sizeof(winceLock),
2101                                         zName);
2102 
2103   /* Set a flag that indicates we're the first to create the memory so it
2104   ** must be zero-initialized */
2105   lastErrno = osGetLastError();
2106   if (lastErrno == ERROR_ALREADY_EXISTS){
2107     bInit = FALSE;
2108   }
2109 
2110   sqlite3_free(zName);
2111 
2112   /* If we succeeded in making the shared memory handle, map it. */
2113   if( pFile->hShared ){
2114     pFile->shared = (winceLock*)osMapViewOfFile(pFile->hShared,
2115              FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
2116     /* If mapping failed, close the shared memory handle and erase it */
2117     if( !pFile->shared ){
2118       pFile->lastErrno = osGetLastError();
2119       winLogError(SQLITE_IOERR, pFile->lastErrno,
2120                   "winceCreateLock2", zFilename);
2121       bLogged = TRUE;
2122       osCloseHandle(pFile->hShared);
2123       pFile->hShared = NULL;
2124     }
2125   }
2126 
2127   /* If shared memory could not be created, then close the mutex and fail */
2128   if( pFile->hShared==NULL ){
2129     if( !bLogged ){
2130       pFile->lastErrno = lastErrno;
2131       winLogError(SQLITE_IOERR, pFile->lastErrno,
2132                   "winceCreateLock3", zFilename);
2133       bLogged = TRUE;
2134     }
2135     winceMutexRelease(pFile->hMutex);
2136     osCloseHandle(pFile->hMutex);
2137     pFile->hMutex = NULL;
2138     return SQLITE_IOERR;
2139   }
2140 
2141   /* Initialize the shared memory if we're supposed to */
2142   if( bInit ){
2143     memset(pFile->shared, 0, sizeof(winceLock));
2144   }
2145 
2146   winceMutexRelease(pFile->hMutex);
2147   return SQLITE_OK;
2148 }
2149 
2150 /*
2151 ** Destroy the part of winFile that deals with wince locks
2152 */
2153 static void winceDestroyLock(winFile *pFile){
2154   if (pFile->hMutex){
2155     /* Acquire the mutex */
2156     winceMutexAcquire(pFile->hMutex);
2157 
2158     /* The following blocks should probably assert in debug mode, but they
2159        are to cleanup in case any locks remained open */
2160     if (pFile->local.nReaders){
2161       pFile->shared->nReaders --;
2162     }
2163     if (pFile->local.bReserved){
2164       pFile->shared->bReserved = FALSE;
2165     }
2166     if (pFile->local.bPending){
2167       pFile->shared->bPending = FALSE;
2168     }
2169     if (pFile->local.bExclusive){
2170       pFile->shared->bExclusive = FALSE;
2171     }
2172 
2173     /* De-reference and close our copy of the shared memory handle */
2174     osUnmapViewOfFile(pFile->shared);
2175     osCloseHandle(pFile->hShared);
2176 
2177     /* Done with the mutex */
2178     winceMutexRelease(pFile->hMutex);
2179     osCloseHandle(pFile->hMutex);
2180     pFile->hMutex = NULL;
2181   }
2182 }
2183 
2184 /*
2185 ** An implementation of the LockFile() API of Windows for CE
2186 */
2187 static BOOL winceLockFile(
2188   LPHANDLE phFile,
2189   DWORD dwFileOffsetLow,
2190   DWORD dwFileOffsetHigh,
2191   DWORD nNumberOfBytesToLockLow,
2192   DWORD nNumberOfBytesToLockHigh
2193 ){
2194   winFile *pFile = HANDLE_TO_WINFILE(phFile);
2195   BOOL bReturn = FALSE;
2196 
2197   UNUSED_PARAMETER(dwFileOffsetHigh);
2198   UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
2199 
2200   if (!pFile->hMutex) return TRUE;
2201   winceMutexAcquire(pFile->hMutex);
2202 
2203   /* Wanting an exclusive lock? */
2204   if (dwFileOffsetLow == (DWORD)SHARED_FIRST
2205        && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
2206     if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
2207        pFile->shared->bExclusive = TRUE;
2208        pFile->local.bExclusive = TRUE;
2209        bReturn = TRUE;
2210     }
2211   }
2212 
2213   /* Want a read-only lock? */
2214   else if (dwFileOffsetLow == (DWORD)SHARED_FIRST &&
2215            nNumberOfBytesToLockLow == 1){
2216     if (pFile->shared->bExclusive == 0){
2217       pFile->local.nReaders ++;
2218       if (pFile->local.nReaders == 1){
2219         pFile->shared->nReaders ++;
2220       }
2221       bReturn = TRUE;
2222     }
2223   }
2224 
2225   /* Want a pending lock? */
2226   else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
2227            && nNumberOfBytesToLockLow == 1){
2228     /* If no pending lock has been acquired, then acquire it */
2229     if (pFile->shared->bPending == 0) {
2230       pFile->shared->bPending = TRUE;
2231       pFile->local.bPending = TRUE;
2232       bReturn = TRUE;
2233     }
2234   }
2235 
2236   /* Want a reserved lock? */
2237   else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
2238            && nNumberOfBytesToLockLow == 1){
2239     if (pFile->shared->bReserved == 0) {
2240       pFile->shared->bReserved = TRUE;
2241       pFile->local.bReserved = TRUE;
2242       bReturn = TRUE;
2243     }
2244   }
2245 
2246   winceMutexRelease(pFile->hMutex);
2247   return bReturn;
2248 }
2249 
2250 /*
2251 ** An implementation of the UnlockFile API of Windows for CE
2252 */
2253 static BOOL winceUnlockFile(
2254   LPHANDLE phFile,
2255   DWORD dwFileOffsetLow,
2256   DWORD dwFileOffsetHigh,
2257   DWORD nNumberOfBytesToUnlockLow,
2258   DWORD nNumberOfBytesToUnlockHigh
2259 ){
2260   winFile *pFile = HANDLE_TO_WINFILE(phFile);
2261   BOOL bReturn = FALSE;
2262 
2263   UNUSED_PARAMETER(dwFileOffsetHigh);
2264   UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);
2265 
2266   if (!pFile->hMutex) return TRUE;
2267   winceMutexAcquire(pFile->hMutex);
2268 
2269   /* Releasing a reader lock or an exclusive lock */
2270   if (dwFileOffsetLow == (DWORD)SHARED_FIRST){
2271     /* Did we have an exclusive lock? */
2272     if (pFile->local.bExclusive){
2273       assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE);
2274       pFile->local.bExclusive = FALSE;
2275       pFile->shared->bExclusive = FALSE;
2276       bReturn = TRUE;
2277     }
2278 
2279     /* Did we just have a reader lock? */
2280     else if (pFile->local.nReaders){
2281       assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE
2282              || nNumberOfBytesToUnlockLow == 1);
2283       pFile->local.nReaders --;
2284       if (pFile->local.nReaders == 0)
2285       {
2286         pFile->shared->nReaders --;
2287       }
2288       bReturn = TRUE;
2289     }
2290   }
2291 
2292   /* Releasing a pending lock */
2293   else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
2294            && nNumberOfBytesToUnlockLow == 1){
2295     if (pFile->local.bPending){
2296       pFile->local.bPending = FALSE;
2297       pFile->shared->bPending = FALSE;
2298       bReturn = TRUE;
2299     }
2300   }
2301   /* Releasing a reserved lock */
2302   else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
2303            && nNumberOfBytesToUnlockLow == 1){
2304     if (pFile->local.bReserved) {
2305       pFile->local.bReserved = FALSE;
2306       pFile->shared->bReserved = FALSE;
2307       bReturn = TRUE;
2308     }
2309   }
2310 
2311   winceMutexRelease(pFile->hMutex);
2312   return bReturn;
2313 }
2314 /*
2315 ** End of the special code for wince
2316 *****************************************************************************/
2317 #endif /* SQLITE_OS_WINCE */
2318 
2319 /*
2320 ** Lock a file region.
2321 */
2322 static BOOL winLockFile(
2323   LPHANDLE phFile,
2324   DWORD flags,
2325   DWORD offsetLow,
2326   DWORD offsetHigh,
2327   DWORD numBytesLow,
2328   DWORD numBytesHigh
2329 ){
2330 #if SQLITE_OS_WINCE
2331   /*
2332   ** NOTE: Windows CE is handled differently here due its lack of the Win32
2333   **       API LockFile.
2334   */
2335   return winceLockFile(phFile, offsetLow, offsetHigh,
2336                        numBytesLow, numBytesHigh);
2337 #else
2338   if( osIsNT() ){
2339     OVERLAPPED ovlp;
2340     memset(&ovlp, 0, sizeof(OVERLAPPED));
2341     ovlp.Offset = offsetLow;
2342     ovlp.OffsetHigh = offsetHigh;
2343     return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
2344   }else{
2345     return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
2346                       numBytesHigh);
2347   }
2348 #endif
2349 }
2350 
2351 /*
2352 ** Unlock a file region.
2353  */
2354 static BOOL winUnlockFile(
2355   LPHANDLE phFile,
2356   DWORD offsetLow,
2357   DWORD offsetHigh,
2358   DWORD numBytesLow,
2359   DWORD numBytesHigh
2360 ){
2361 #if SQLITE_OS_WINCE
2362   /*
2363   ** NOTE: Windows CE is handled differently here due its lack of the Win32
2364   **       API UnlockFile.
2365   */
2366   return winceUnlockFile(phFile, offsetLow, offsetHigh,
2367                          numBytesLow, numBytesHigh);
2368 #else
2369   if( osIsNT() ){
2370     OVERLAPPED ovlp;
2371     memset(&ovlp, 0, sizeof(OVERLAPPED));
2372     ovlp.Offset = offsetLow;
2373     ovlp.OffsetHigh = offsetHigh;
2374     return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
2375   }else{
2376     return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
2377                         numBytesHigh);
2378   }
2379 #endif
2380 }
2381 
2382 /*****************************************************************************
2383 ** The next group of routines implement the I/O methods specified
2384 ** by the sqlite3_io_methods object.
2385 ******************************************************************************/
2386 
2387 /*
2388 ** Some Microsoft compilers lack this definition.
2389 */
2390 #ifndef INVALID_SET_FILE_POINTER
2391 # define INVALID_SET_FILE_POINTER ((DWORD)-1)
2392 #endif
2393 
2394 /*
2395 ** Move the current position of the file handle passed as the first
2396 ** argument to offset iOffset within the file. If successful, return 0.
2397 ** Otherwise, set pFile->lastErrno and return non-zero.
2398 */
2399 static int winSeekFile(winFile *pFile, sqlite3_int64 iOffset){
2400 #if !SQLITE_OS_WINRT
2401   LONG upperBits;                 /* Most sig. 32 bits of new offset */
2402   LONG lowerBits;                 /* Least sig. 32 bits of new offset */
2403   DWORD dwRet;                    /* Value returned by SetFilePointer() */
2404   DWORD lastErrno;                /* Value returned by GetLastError() */
2405 
2406   OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
2407 
2408   upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
2409   lowerBits = (LONG)(iOffset & 0xffffffff);
2410 
2411   /* API oddity: If successful, SetFilePointer() returns a dword
2412   ** containing the lower 32-bits of the new file-offset. Or, if it fails,
2413   ** it returns INVALID_SET_FILE_POINTER. However according to MSDN,
2414   ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine
2415   ** whether an error has actually occurred, it is also necessary to call
2416   ** GetLastError().
2417   */
2418   dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
2419 
2420   if( (dwRet==INVALID_SET_FILE_POINTER
2421       && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
2422     pFile->lastErrno = lastErrno;
2423     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
2424                 "winSeekFile", pFile->zPath);
2425     OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
2426     return 1;
2427   }
2428 
2429   OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
2430   return 0;
2431 #else
2432   /*
2433   ** Same as above, except that this implementation works for WinRT.
2434   */
2435 
2436   LARGE_INTEGER x;                /* The new offset */
2437   BOOL bRet;                      /* Value returned by SetFilePointerEx() */
2438 
2439   x.QuadPart = iOffset;
2440   bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);
2441 
2442   if(!bRet){
2443     pFile->lastErrno = osGetLastError();
2444     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
2445                 "winSeekFile", pFile->zPath);
2446     OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
2447     return 1;
2448   }
2449 
2450   OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
2451   return 0;
2452 #endif
2453 }
2454 
2455 #if SQLITE_MAX_MMAP_SIZE>0
2456 /* Forward references to VFS helper methods used for memory mapped files */
2457 static int winMapfile(winFile*, sqlite3_int64);
2458 static int winUnmapfile(winFile*);
2459 #endif
2460 
2461 /*
2462 ** Close a file.
2463 **
2464 ** It is reported that an attempt to close a handle might sometimes
2465 ** fail.  This is a very unreasonable result, but Windows is notorious
2466 ** for being unreasonable so I do not doubt that it might happen.  If
2467 ** the close fails, we pause for 100 milliseconds and try again.  As
2468 ** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
2469 ** giving up and returning an error.
2470 */
2471 #define MX_CLOSE_ATTEMPT 3
2472 static int winClose(sqlite3_file *id){
2473   int rc, cnt = 0;
2474   winFile *pFile = (winFile*)id;
2475 
2476   assert( id!=0 );
2477 #ifndef SQLITE_OMIT_WAL
2478   assert( pFile->pShm==0 );
2479 #endif
2480   assert( pFile->h!=NULL && pFile->h!=INVALID_HANDLE_VALUE );
2481   OSTRACE(("CLOSE pid=%lu, pFile=%p, file=%p\n",
2482            osGetCurrentProcessId(), pFile, pFile->h));
2483 
2484 #if SQLITE_MAX_MMAP_SIZE>0
2485   winUnmapfile(pFile);
2486 #endif
2487 
2488   do{
2489     rc = osCloseHandle(pFile->h);
2490     /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
2491   }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (sqlite3_win32_sleep(100), 1) );
2492 #if SQLITE_OS_WINCE
2493 #define WINCE_DELETION_ATTEMPTS 3
2494   winceDestroyLock(pFile);
2495   if( pFile->zDeleteOnClose ){
2496     int cnt = 0;
2497     while(
2498            osDeleteFileW(pFile->zDeleteOnClose)==0
2499         && osGetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff
2500         && cnt++ < WINCE_DELETION_ATTEMPTS
2501     ){
2502        sqlite3_win32_sleep(100);  /* Wait a little before trying again */
2503     }
2504     sqlite3_free(pFile->zDeleteOnClose);
2505   }
2506 #endif
2507   if( rc ){
2508     pFile->h = NULL;
2509   }
2510   OpenCounter(-1);
2511   OSTRACE(("CLOSE pid=%lu, pFile=%p, file=%p, rc=%s\n",
2512            osGetCurrentProcessId(), pFile, pFile->h, rc ? "ok" : "failed"));
2513   return rc ? SQLITE_OK
2514             : winLogError(SQLITE_IOERR_CLOSE, osGetLastError(),
2515                           "winClose", pFile->zPath);
2516 }
2517 
2518 /*
2519 ** Read data from a file into a buffer.  Return SQLITE_OK if all
2520 ** bytes were read successfully and SQLITE_IOERR if anything goes
2521 ** wrong.
2522 */
2523 static int winRead(
2524   sqlite3_file *id,          /* File to read from */
2525   void *pBuf,                /* Write content into this buffer */
2526   int amt,                   /* Number of bytes to read */
2527   sqlite3_int64 offset       /* Begin reading at this offset */
2528 ){
2529 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2530   OVERLAPPED overlapped;          /* The offset for ReadFile. */
2531 #endif
2532   winFile *pFile = (winFile*)id;  /* file handle */
2533   DWORD nRead;                    /* Number of bytes actually read from file */
2534   int nRetry = 0;                 /* Number of retrys */
2535 
2536   assert( id!=0 );
2537   assert( amt>0 );
2538   assert( offset>=0 );
2539   SimulateIOError(return SQLITE_IOERR_READ);
2540   OSTRACE(("READ pid=%lu, pFile=%p, file=%p, buffer=%p, amount=%d, "
2541            "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
2542            pFile->h, pBuf, amt, offset, pFile->locktype));
2543 
2544 #if SQLITE_MAX_MMAP_SIZE>0
2545   /* Deal with as much of this read request as possible by transfering
2546   ** data from the memory mapping using memcpy().  */
2547   if( offset<pFile->mmapSize ){
2548     if( offset+amt <= pFile->mmapSize ){
2549       memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
2550       OSTRACE(("READ-MMAP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2551                osGetCurrentProcessId(), pFile, pFile->h));
2552       return SQLITE_OK;
2553     }else{
2554       int nCopy = (int)(pFile->mmapSize - offset);
2555       memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
2556       pBuf = &((u8 *)pBuf)[nCopy];
2557       amt -= nCopy;
2558       offset += nCopy;
2559     }
2560   }
2561 #endif
2562 
2563 #if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
2564   if( winSeekFile(pFile, offset) ){
2565     OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_FULL\n",
2566              osGetCurrentProcessId(), pFile, pFile->h));
2567     return SQLITE_FULL;
2568   }
2569   while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
2570 #else
2571   memset(&overlapped, 0, sizeof(OVERLAPPED));
2572   overlapped.Offset = (LONG)(offset & 0xffffffff);
2573   overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2574   while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
2575          osGetLastError()!=ERROR_HANDLE_EOF ){
2576 #endif
2577     DWORD lastErrno;
2578     if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
2579     pFile->lastErrno = lastErrno;
2580     OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_READ\n",
2581              osGetCurrentProcessId(), pFile, pFile->h));
2582     return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
2583                        "winRead", pFile->zPath);
2584   }
2585   winLogIoerr(nRetry, __LINE__);
2586   if( nRead<(DWORD)amt ){
2587     /* Unread parts of the buffer must be zero-filled */
2588     memset(&((char*)pBuf)[nRead], 0, amt-nRead);
2589     OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_SHORT_READ\n",
2590              osGetCurrentProcessId(), pFile, pFile->h));
2591     return SQLITE_IOERR_SHORT_READ;
2592   }
2593 
2594   OSTRACE(("READ pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2595            osGetCurrentProcessId(), pFile, pFile->h));
2596   return SQLITE_OK;
2597 }
2598 
2599 /*
2600 ** Write data from a buffer into a file.  Return SQLITE_OK on success
2601 ** or some other error code on failure.
2602 */
2603 static int winWrite(
2604   sqlite3_file *id,               /* File to write into */
2605   const void *pBuf,               /* The bytes to be written */
2606   int amt,                        /* Number of bytes to write */
2607   sqlite3_int64 offset            /* Offset into the file to begin writing at */
2608 ){
2609   int rc = 0;                     /* True if error has occurred, else false */
2610   winFile *pFile = (winFile*)id;  /* File handle */
2611   int nRetry = 0;                 /* Number of retries */
2612 
2613   assert( amt>0 );
2614   assert( pFile );
2615   SimulateIOError(return SQLITE_IOERR_WRITE);
2616   SimulateDiskfullError(return SQLITE_FULL);
2617 
2618   OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, buffer=%p, amount=%d, "
2619            "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
2620            pFile->h, pBuf, amt, offset, pFile->locktype));
2621 
2622 #if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
2623   /* Deal with as much of this write request as possible by transfering
2624   ** data from the memory mapping using memcpy().  */
2625   if( offset<pFile->mmapSize ){
2626     if( offset+amt <= pFile->mmapSize ){
2627       memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
2628       OSTRACE(("WRITE-MMAP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2629                osGetCurrentProcessId(), pFile, pFile->h));
2630       return SQLITE_OK;
2631     }else{
2632       int nCopy = (int)(pFile->mmapSize - offset);
2633       memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
2634       pBuf = &((u8 *)pBuf)[nCopy];
2635       amt -= nCopy;
2636       offset += nCopy;
2637     }
2638   }
2639 #endif
2640 
2641 #if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
2642   rc = winSeekFile(pFile, offset);
2643   if( rc==0 ){
2644 #else
2645   {
2646 #endif
2647 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2648     OVERLAPPED overlapped;        /* The offset for WriteFile. */
2649 #endif
2650     u8 *aRem = (u8 *)pBuf;        /* Data yet to be written */
2651     int nRem = amt;               /* Number of bytes yet to be written */
2652     DWORD nWrite;                 /* Bytes written by each WriteFile() call */
2653     DWORD lastErrno = NO_ERROR;   /* Value returned by GetLastError() */
2654 
2655 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2656     memset(&overlapped, 0, sizeof(OVERLAPPED));
2657     overlapped.Offset = (LONG)(offset & 0xffffffff);
2658     overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2659 #endif
2660 
2661     while( nRem>0 ){
2662 #if SQLITE_OS_WINCE || defined(SQLITE_WIN32_NO_OVERLAPPED)
2663       if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
2664 #else
2665       if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
2666 #endif
2667         if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
2668         break;
2669       }
2670       assert( nWrite==0 || nWrite<=(DWORD)nRem );
2671       if( nWrite==0 || nWrite>(DWORD)nRem ){
2672         lastErrno = osGetLastError();
2673         break;
2674       }
2675 #if !SQLITE_OS_WINCE && !defined(SQLITE_WIN32_NO_OVERLAPPED)
2676       offset += nWrite;
2677       overlapped.Offset = (LONG)(offset & 0xffffffff);
2678       overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2679 #endif
2680       aRem += nWrite;
2681       nRem -= nWrite;
2682     }
2683     if( nRem>0 ){
2684       pFile->lastErrno = lastErrno;
2685       rc = 1;
2686     }
2687   }
2688 
2689   if( rc ){
2690     if(   ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
2691        || ( pFile->lastErrno==ERROR_DISK_FULL )){
2692       OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_FULL\n",
2693                osGetCurrentProcessId(), pFile, pFile->h));
2694       return winLogError(SQLITE_FULL, pFile->lastErrno,
2695                          "winWrite1", pFile->zPath);
2696     }
2697     OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_WRITE\n",
2698              osGetCurrentProcessId(), pFile, pFile->h));
2699     return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
2700                        "winWrite2", pFile->zPath);
2701   }else{
2702     winLogIoerr(nRetry, __LINE__);
2703   }
2704   OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2705            osGetCurrentProcessId(), pFile, pFile->h));
2706   return SQLITE_OK;
2707 }
2708 
2709 /*
2710 ** Truncate an open file to a specified size
2711 */
2712 static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
2713   winFile *pFile = (winFile*)id;  /* File handle object */
2714   int rc = SQLITE_OK;             /* Return code for this function */
2715   DWORD lastErrno;
2716 
2717   assert( pFile );
2718   SimulateIOError(return SQLITE_IOERR_TRUNCATE);
2719   OSTRACE(("TRUNCATE pid=%lu, pFile=%p, file=%p, size=%lld, lock=%d\n",
2720            osGetCurrentProcessId(), pFile, pFile->h, nByte, pFile->locktype));
2721 
2722   /* If the user has configured a chunk-size for this file, truncate the
2723   ** file so that it consists of an integer number of chunks (i.e. the
2724   ** actual file size after the operation may be larger than the requested
2725   ** size).
2726   */
2727   if( pFile->szChunk>0 ){
2728     nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
2729   }
2730 
2731   /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
2732   if( winSeekFile(pFile, nByte) ){
2733     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
2734                      "winTruncate1", pFile->zPath);
2735   }else if( 0==osSetEndOfFile(pFile->h) &&
2736             ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
2737     pFile->lastErrno = lastErrno;
2738     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
2739                      "winTruncate2", pFile->zPath);
2740   }
2741 
2742 #if SQLITE_MAX_MMAP_SIZE>0
2743   /* If the file was truncated to a size smaller than the currently
2744   ** mapped region, reduce the effective mapping size as well. SQLite will
2745   ** use read() and write() to access data beyond this point from now on.
2746   */
2747   if( pFile->pMapRegion && nByte<pFile->mmapSize ){
2748     pFile->mmapSize = nByte;
2749   }
2750 #endif
2751 
2752   OSTRACE(("TRUNCATE pid=%lu, pFile=%p, file=%p, rc=%s\n",
2753            osGetCurrentProcessId(), pFile, pFile->h, sqlite3ErrName(rc)));
2754   return rc;
2755 }
2756 
2757 #ifdef SQLITE_TEST
2758 /*
2759 ** Count the number of fullsyncs and normal syncs.  This is used to test
2760 ** that syncs and fullsyncs are occuring at the right times.
2761 */
2762 int sqlite3_sync_count = 0;
2763 int sqlite3_fullsync_count = 0;
2764 #endif
2765 
2766 /*
2767 ** Make sure all writes to a particular file are committed to disk.
2768 */
2769 static int winSync(sqlite3_file *id, int flags){
2770 #ifndef SQLITE_NO_SYNC
2771   /*
2772   ** Used only when SQLITE_NO_SYNC is not defined.
2773    */
2774   BOOL rc;
2775 #endif
2776 #if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || \
2777     defined(SQLITE_HAVE_OS_TRACE)
2778   /*
2779   ** Used when SQLITE_NO_SYNC is not defined and by the assert() and/or
2780   ** OSTRACE() macros.
2781    */
2782   winFile *pFile = (winFile*)id;
2783 #else
2784   UNUSED_PARAMETER(id);
2785 #endif
2786 
2787   assert( pFile );
2788   /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
2789   assert((flags&0x0F)==SQLITE_SYNC_NORMAL
2790       || (flags&0x0F)==SQLITE_SYNC_FULL
2791   );
2792 
2793   /* Unix cannot, but some systems may return SQLITE_FULL from here. This
2794   ** line is to test that doing so does not cause any problems.
2795   */
2796   SimulateDiskfullError( return SQLITE_FULL );
2797 
2798   OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, flags=%x, lock=%d\n",
2799            osGetCurrentProcessId(), pFile, pFile->h, flags,
2800            pFile->locktype));
2801 
2802 #ifndef SQLITE_TEST
2803   UNUSED_PARAMETER(flags);
2804 #else
2805   if( (flags&0x0F)==SQLITE_SYNC_FULL ){
2806     sqlite3_fullsync_count++;
2807   }
2808   sqlite3_sync_count++;
2809 #endif
2810 
2811   /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
2812   ** no-op
2813   */
2814 #ifdef SQLITE_NO_SYNC
2815   OSTRACE(("SYNC-NOP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2816            osGetCurrentProcessId(), pFile, pFile->h));
2817   return SQLITE_OK;
2818 #else
2819 #if SQLITE_MAX_MMAP_SIZE>0
2820   if( pFile->pMapRegion ){
2821     if( osFlushViewOfFile(pFile->pMapRegion, 0) ){
2822       OSTRACE(("SYNC-MMAP pid=%lu, pFile=%p, pMapRegion=%p, "
2823                "rc=SQLITE_OK\n", osGetCurrentProcessId(),
2824                pFile, pFile->pMapRegion));
2825     }else{
2826       pFile->lastErrno = osGetLastError();
2827       OSTRACE(("SYNC-MMAP pid=%lu, pFile=%p, pMapRegion=%p, "
2828                "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(),
2829                pFile, pFile->pMapRegion));
2830       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
2831                          "winSync1", pFile->zPath);
2832     }
2833   }
2834 #endif
2835   rc = osFlushFileBuffers(pFile->h);
2836   SimulateIOError( rc=FALSE );
2837   if( rc ){
2838     OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
2839              osGetCurrentProcessId(), pFile, pFile->h));
2840     return SQLITE_OK;
2841   }else{
2842     pFile->lastErrno = osGetLastError();
2843     OSTRACE(("SYNC pid=%lu, pFile=%p, file=%p, rc=SQLITE_IOERR_FSYNC\n",
2844              osGetCurrentProcessId(), pFile, pFile->h));
2845     return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
2846                        "winSync2", pFile->zPath);
2847   }
2848 #endif
2849 }
2850 
2851 /*
2852 ** Determine the current size of a file in bytes
2853 */
2854 static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
2855   winFile *pFile = (winFile*)id;
2856   int rc = SQLITE_OK;
2857 
2858   assert( id!=0 );
2859   assert( pSize!=0 );
2860   SimulateIOError(return SQLITE_IOERR_FSTAT);
2861   OSTRACE(("SIZE file=%p, pSize=%p\n", pFile->h, pSize));
2862 
2863 #if SQLITE_OS_WINRT
2864   {
2865     FILE_STANDARD_INFO info;
2866     if( osGetFileInformationByHandleEx(pFile->h, FileStandardInfo,
2867                                      &info, sizeof(info)) ){
2868       *pSize = info.EndOfFile.QuadPart;
2869     }else{
2870       pFile->lastErrno = osGetLastError();
2871       rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
2872                        "winFileSize", pFile->zPath);
2873     }
2874   }
2875 #else
2876   {
2877     DWORD upperBits;
2878     DWORD lowerBits;
2879     DWORD lastErrno;
2880 
2881     lowerBits = osGetFileSize(pFile->h, &upperBits);
2882     *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
2883     if(   (lowerBits == INVALID_FILE_SIZE)
2884        && ((lastErrno = osGetLastError())!=NO_ERROR) ){
2885       pFile->lastErrno = lastErrno;
2886       rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
2887                        "winFileSize", pFile->zPath);
2888     }
2889   }
2890 #endif
2891   OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
2892            pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
2893   return rc;
2894 }
2895 
2896 /*
2897 ** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
2898 */
2899 #ifndef LOCKFILE_FAIL_IMMEDIATELY
2900 # define LOCKFILE_FAIL_IMMEDIATELY 1
2901 #endif
2902 
2903 #ifndef LOCKFILE_EXCLUSIVE_LOCK
2904 # define LOCKFILE_EXCLUSIVE_LOCK 2
2905 #endif
2906 
2907 /*
2908 ** Historically, SQLite has used both the LockFile and LockFileEx functions.
2909 ** When the LockFile function was used, it was always expected to fail
2910 ** immediately if the lock could not be obtained.  Also, it always expected to
2911 ** obtain an exclusive lock.  These flags are used with the LockFileEx function
2912 ** and reflect those expectations; therefore, they should not be changed.
2913 */
2914 #ifndef SQLITE_LOCKFILE_FLAGS
2915 # define SQLITE_LOCKFILE_FLAGS   (LOCKFILE_FAIL_IMMEDIATELY | \
2916                                   LOCKFILE_EXCLUSIVE_LOCK)
2917 #endif
2918 
2919 /*
2920 ** Currently, SQLite never calls the LockFileEx function without wanting the
2921 ** call to fail immediately if the lock cannot be obtained.
2922 */
2923 #ifndef SQLITE_LOCKFILEEX_FLAGS
2924 # define SQLITE_LOCKFILEEX_FLAGS (LOCKFILE_FAIL_IMMEDIATELY)
2925 #endif
2926 
2927 /*
2928 ** Acquire a reader lock.
2929 ** Different API routines are called depending on whether or not this
2930 ** is Win9x or WinNT.
2931 */
2932 static int winGetReadLock(winFile *pFile){
2933   int res;
2934   OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
2935   if( osIsNT() ){
2936 #if SQLITE_OS_WINCE
2937     /*
2938     ** NOTE: Windows CE is handled differently here due its lack of the Win32
2939     **       API LockFileEx.
2940     */
2941     res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
2942 #else
2943     res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS, SHARED_FIRST, 0,
2944                       SHARED_SIZE, 0);
2945 #endif
2946   }
2947 #ifdef SQLITE_WIN32_HAS_ANSI
2948   else{
2949     int lk;
2950     sqlite3_randomness(sizeof(lk), &lk);
2951     pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
2952     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
2953                       SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
2954   }
2955 #endif
2956   if( res == 0 ){
2957     pFile->lastErrno = osGetLastError();
2958     /* No need to log a failure to lock */
2959   }
2960   OSTRACE(("READ-LOCK file=%p, result=%d\n", pFile->h, res));
2961   return res;
2962 }
2963 
2964 /*
2965 ** Undo a readlock
2966 */
2967 static int winUnlockReadLock(winFile *pFile){
2968   int res;
2969   DWORD lastErrno;
2970   OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
2971   if( osIsNT() ){
2972     res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
2973   }
2974 #ifdef SQLITE_WIN32_HAS_ANSI
2975   else{
2976     res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
2977   }
2978 #endif
2979   if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
2980     pFile->lastErrno = lastErrno;
2981     winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
2982                 "winUnlockReadLock", pFile->zPath);
2983   }
2984   OSTRACE(("READ-UNLOCK file=%p, result=%d\n", pFile->h, res));
2985   return res;
2986 }
2987 
2988 /*
2989 ** Lock the file with the lock specified by parameter locktype - one
2990 ** of the following:
2991 **
2992 **     (1) SHARED_LOCK
2993 **     (2) RESERVED_LOCK
2994 **     (3) PENDING_LOCK
2995 **     (4) EXCLUSIVE_LOCK
2996 **
2997 ** Sometimes when requesting one lock state, additional lock states
2998 ** are inserted in between.  The locking might fail on one of the later
2999 ** transitions leaving the lock state different from what it started but
3000 ** still short of its goal.  The following chart shows the allowed
3001 ** transitions and the inserted intermediate states:
3002 **
3003 **    UNLOCKED -> SHARED
3004 **    SHARED -> RESERVED
3005 **    SHARED -> (PENDING) -> EXCLUSIVE
3006 **    RESERVED -> (PENDING) -> EXCLUSIVE
3007 **    PENDING -> EXCLUSIVE
3008 **
3009 ** This routine will only increase a lock.  The winUnlock() routine
3010 ** erases all locks at once and returns us immediately to locking level 0.
3011 ** It is not possible to lower the locking level one step at a time.  You
3012 ** must go straight to locking level 0.
3013 */
3014 static int winLock(sqlite3_file *id, int locktype){
3015   int rc = SQLITE_OK;    /* Return code from subroutines */
3016   int res = 1;           /* Result of a Windows lock call */
3017   int newLocktype;       /* Set pFile->locktype to this value before exiting */
3018   int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
3019   winFile *pFile = (winFile*)id;
3020   DWORD lastErrno = NO_ERROR;
3021 
3022   assert( id!=0 );
3023   OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
3024            pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
3025 
3026   /* If there is already a lock of this type or more restrictive on the
3027   ** OsFile, do nothing. Don't use the end_lock: exit path, as
3028   ** sqlite3OsEnterMutex() hasn't been called yet.
3029   */
3030   if( pFile->locktype>=locktype ){
3031     OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
3032     return SQLITE_OK;
3033   }
3034 
3035   /* Do not allow any kind of write-lock on a read-only database
3036   */
3037   if( (pFile->ctrlFlags & WINFILE_RDONLY)!=0 && locktype>=RESERVED_LOCK ){
3038     return SQLITE_IOERR_LOCK;
3039   }
3040 
3041   /* Make sure the locking sequence is correct
3042   */
3043   assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
3044   assert( locktype!=PENDING_LOCK );
3045   assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
3046 
3047   /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
3048   ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
3049   ** the PENDING_LOCK byte is temporary.
3050   */
3051   newLocktype = pFile->locktype;
3052   if(   (pFile->locktype==NO_LOCK)
3053      || (   (locktype==EXCLUSIVE_LOCK)
3054          && (pFile->locktype==RESERVED_LOCK))
3055   ){
3056     int cnt = 3;
3057     while( cnt-->0 && (res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
3058                                          PENDING_BYTE, 0, 1, 0))==0 ){
3059       /* Try 3 times to get the pending lock.  This is needed to work
3060       ** around problems caused by indexing and/or anti-virus software on
3061       ** Windows systems.
3062       ** If you are using this code as a model for alternative VFSes, do not
3063       ** copy this retry logic.  It is a hack intended for Windows only.
3064       */
3065       lastErrno = osGetLastError();
3066       OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, result=%d\n",
3067                pFile->h, cnt, res));
3068       if( lastErrno==ERROR_INVALID_HANDLE ){
3069         pFile->lastErrno = lastErrno;
3070         rc = SQLITE_IOERR_LOCK;
3071         OSTRACE(("LOCK-FAIL file=%p, count=%d, rc=%s\n",
3072                  pFile->h, cnt, sqlite3ErrName(rc)));
3073         return rc;
3074       }
3075       if( cnt ) sqlite3_win32_sleep(1);
3076     }
3077     gotPendingLock = res;
3078     if( !res ){
3079       lastErrno = osGetLastError();
3080     }
3081   }
3082 
3083   /* Acquire a shared lock
3084   */
3085   if( locktype==SHARED_LOCK && res ){
3086     assert( pFile->locktype==NO_LOCK );
3087     res = winGetReadLock(pFile);
3088     if( res ){
3089       newLocktype = SHARED_LOCK;
3090     }else{
3091       lastErrno = osGetLastError();
3092     }
3093   }
3094 
3095   /* Acquire a RESERVED lock
3096   */
3097   if( locktype==RESERVED_LOCK && res ){
3098     assert( pFile->locktype==SHARED_LOCK );
3099     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, RESERVED_BYTE, 0, 1, 0);
3100     if( res ){
3101       newLocktype = RESERVED_LOCK;
3102     }else{
3103       lastErrno = osGetLastError();
3104     }
3105   }
3106 
3107   /* Acquire a PENDING lock
3108   */
3109   if( locktype==EXCLUSIVE_LOCK && res ){
3110     newLocktype = PENDING_LOCK;
3111     gotPendingLock = 0;
3112   }
3113 
3114   /* Acquire an EXCLUSIVE lock
3115   */
3116   if( locktype==EXCLUSIVE_LOCK && res ){
3117     assert( pFile->locktype>=SHARED_LOCK );
3118     res = winUnlockReadLock(pFile);
3119     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
3120                       SHARED_SIZE, 0);
3121     if( res ){
3122       newLocktype = EXCLUSIVE_LOCK;
3123     }else{
3124       lastErrno = osGetLastError();
3125       winGetReadLock(pFile);
3126     }
3127   }
3128 
3129   /* If we are holding a PENDING lock that ought to be released, then
3130   ** release it now.
3131   */
3132   if( gotPendingLock && locktype==SHARED_LOCK ){
3133     winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
3134   }
3135 
3136   /* Update the state of the lock has held in the file descriptor then
3137   ** return the appropriate result code.
3138   */
3139   if( res ){
3140     rc = SQLITE_OK;
3141   }else{
3142     pFile->lastErrno = lastErrno;
3143     rc = SQLITE_BUSY;
3144     OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
3145              pFile->h, locktype, newLocktype));
3146   }
3147   pFile->locktype = (u8)newLocktype;
3148   OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
3149            pFile->h, pFile->locktype, sqlite3ErrName(rc)));
3150   return rc;
3151 }
3152 
3153 /*
3154 ** This routine checks if there is a RESERVED lock held on the specified
3155 ** file by this or any other process. If such a lock is held, return
3156 ** non-zero, otherwise zero.
3157 */
3158 static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
3159   int res;
3160   winFile *pFile = (winFile*)id;
3161 
3162   SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
3163   OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));
3164 
3165   assert( id!=0 );
3166   if( pFile->locktype>=RESERVED_LOCK ){
3167     res = 1;
3168     OSTRACE(("TEST-WR-LOCK file=%p, result=%d (local)\n", pFile->h, res));
3169   }else{
3170     res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE,0,1,0);
3171     if( res ){
3172       winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
3173     }
3174     res = !res;
3175     OSTRACE(("TEST-WR-LOCK file=%p, result=%d (remote)\n", pFile->h, res));
3176   }
3177   *pResOut = res;
3178   OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
3179            pFile->h, pResOut, *pResOut));
3180   return SQLITE_OK;
3181 }
3182 
3183 /*
3184 ** Lower the locking level on file descriptor id to locktype.  locktype
3185 ** must be either NO_LOCK or SHARED_LOCK.
3186 **
3187 ** If the locking level of the file descriptor is already at or below
3188 ** the requested locking level, this routine is a no-op.
3189 **
3190 ** It is not possible for this routine to fail if the second argument
3191 ** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
3192 ** might return SQLITE_IOERR;
3193 */
3194 static int winUnlock(sqlite3_file *id, int locktype){
3195   int type;
3196   winFile *pFile = (winFile*)id;
3197   int rc = SQLITE_OK;
3198   assert( pFile!=0 );
3199   assert( locktype<=SHARED_LOCK );
3200   OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
3201            pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
3202   type = pFile->locktype;
3203   if( type>=EXCLUSIVE_LOCK ){
3204     winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
3205     if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
3206       /* This should never happen.  We should always be able to
3207       ** reacquire the read lock */
3208       rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
3209                        "winUnlock", pFile->zPath);
3210     }
3211   }
3212   if( type>=RESERVED_LOCK ){
3213     winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
3214   }
3215   if( locktype==NO_LOCK && type>=SHARED_LOCK ){
3216     winUnlockReadLock(pFile);
3217   }
3218   if( type>=PENDING_LOCK ){
3219     winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
3220   }
3221   pFile->locktype = (u8)locktype;
3222   OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
3223            pFile->h, pFile->locktype, sqlite3ErrName(rc)));
3224   return rc;
3225 }
3226 
3227 /*
3228 ** If *pArg is initially negative then this is a query.  Set *pArg to
3229 ** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
3230 **
3231 ** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
3232 */
3233 static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
3234   if( *pArg<0 ){
3235     *pArg = (pFile->ctrlFlags & mask)!=0;
3236   }else if( (*pArg)==0 ){
3237     pFile->ctrlFlags &= ~mask;
3238   }else{
3239     pFile->ctrlFlags |= mask;
3240   }
3241 }
3242 
3243 /* Forward references to VFS helper methods used for temporary files */
3244 static int winGetTempname(sqlite3_vfs *, char **);
3245 static int winIsDir(const void *);
3246 static BOOL winIsDriveLetterAndColon(const char *);
3247 
3248 /*
3249 ** Control and query of the open file handle.
3250 */
3251 static int winFileControl(sqlite3_file *id, int op, void *pArg){
3252   winFile *pFile = (winFile*)id;
3253   OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
3254   switch( op ){
3255     case SQLITE_FCNTL_LOCKSTATE: {
3256       *(int*)pArg = pFile->locktype;
3257       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3258       return SQLITE_OK;
3259     }
3260     case SQLITE_FCNTL_LAST_ERRNO: {
3261       *(int*)pArg = (int)pFile->lastErrno;
3262       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3263       return SQLITE_OK;
3264     }
3265     case SQLITE_FCNTL_CHUNK_SIZE: {
3266       pFile->szChunk = *(int *)pArg;
3267       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3268       return SQLITE_OK;
3269     }
3270     case SQLITE_FCNTL_SIZE_HINT: {
3271       if( pFile->szChunk>0 ){
3272         sqlite3_int64 oldSz;
3273         int rc = winFileSize(id, &oldSz);
3274         if( rc==SQLITE_OK ){
3275           sqlite3_int64 newSz = *(sqlite3_int64*)pArg;
3276           if( newSz>oldSz ){
3277             SimulateIOErrorBenign(1);
3278             rc = winTruncate(id, newSz);
3279             SimulateIOErrorBenign(0);
3280           }
3281         }
3282         OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3283         return rc;
3284       }
3285       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3286       return SQLITE_OK;
3287     }
3288     case SQLITE_FCNTL_PERSIST_WAL: {
3289       winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
3290       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3291       return SQLITE_OK;
3292     }
3293     case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
3294       winModeBit(pFile, WINFILE_PSOW, (int*)pArg);
3295       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3296       return SQLITE_OK;
3297     }
3298     case SQLITE_FCNTL_VFSNAME: {
3299       *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
3300       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3301       return SQLITE_OK;
3302     }
3303     case SQLITE_FCNTL_WIN32_AV_RETRY: {
3304       int *a = (int*)pArg;
3305       if( a[0]>0 ){
3306         winIoerrRetry = a[0];
3307       }else{
3308         a[0] = winIoerrRetry;
3309       }
3310       if( a[1]>0 ){
3311         winIoerrRetryDelay = a[1];
3312       }else{
3313         a[1] = winIoerrRetryDelay;
3314       }
3315       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3316       return SQLITE_OK;
3317     }
3318 #ifdef SQLITE_TEST
3319     case SQLITE_FCNTL_WIN32_SET_HANDLE: {
3320       LPHANDLE phFile = (LPHANDLE)pArg;
3321       HANDLE hOldFile = pFile->h;
3322       pFile->h = *phFile;
3323       *phFile = hOldFile;
3324       OSTRACE(("FCNTL oldFile=%p, newFile=%p, rc=SQLITE_OK\n",
3325                hOldFile, pFile->h));
3326       return SQLITE_OK;
3327     }
3328 #endif
3329     case SQLITE_FCNTL_TEMPFILENAME: {
3330       char *zTFile = 0;
3331       int rc = winGetTempname(pFile->pVfs, &zTFile);
3332       if( rc==SQLITE_OK ){
3333         *(char**)pArg = zTFile;
3334       }
3335       OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3336       return rc;
3337     }
3338 #if SQLITE_MAX_MMAP_SIZE>0
3339     case SQLITE_FCNTL_MMAP_SIZE: {
3340       i64 newLimit = *(i64*)pArg;
3341       int rc = SQLITE_OK;
3342       if( newLimit>sqlite3GlobalConfig.mxMmap ){
3343         newLimit = sqlite3GlobalConfig.mxMmap;
3344       }
3345       *(i64*)pArg = pFile->mmapSizeMax;
3346       if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
3347         pFile->mmapSizeMax = newLimit;
3348         if( pFile->mmapSize>0 ){
3349           winUnmapfile(pFile);
3350           rc = winMapfile(pFile, -1);
3351         }
3352       }
3353       OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3354       return rc;
3355     }
3356 #endif
3357   }
3358   OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
3359   return SQLITE_NOTFOUND;
3360 }
3361 
3362 /*
3363 ** Return the sector size in bytes of the underlying block device for
3364 ** the specified file. This is almost always 512 bytes, but may be
3365 ** larger for some devices.
3366 **
3367 ** SQLite code assumes this function cannot fail. It also assumes that
3368 ** if two files are created in the same file-system directory (i.e.
3369 ** a database and its journal file) that the sector size will be the
3370 ** same for both.
3371 */
3372 static int winSectorSize(sqlite3_file *id){
3373   (void)id;
3374   return SQLITE_DEFAULT_SECTOR_SIZE;
3375 }
3376 
3377 /*
3378 ** Return a vector of device characteristics.
3379 */
3380 static int winDeviceCharacteristics(sqlite3_file *id){
3381   winFile *p = (winFile*)id;
3382   return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
3383          ((p->ctrlFlags & WINFILE_PSOW)?SQLITE_IOCAP_POWERSAFE_OVERWRITE:0);
3384 }
3385 
3386 /*
3387 ** Windows will only let you create file view mappings
3388 ** on allocation size granularity boundaries.
3389 ** During sqlite3_os_init() we do a GetSystemInfo()
3390 ** to get the granularity size.
3391 */
3392 static SYSTEM_INFO winSysInfo;
3393 
3394 #ifndef SQLITE_OMIT_WAL
3395 
3396 /*
3397 ** Helper functions to obtain and relinquish the global mutex. The
3398 ** global mutex is used to protect the winLockInfo objects used by
3399 ** this file, all of which may be shared by multiple threads.
3400 **
3401 ** Function winShmMutexHeld() is used to assert() that the global mutex
3402 ** is held when required. This function is only used as part of assert()
3403 ** statements. e.g.
3404 **
3405 **   winShmEnterMutex()
3406 **     assert( winShmMutexHeld() );
3407 **   winShmLeaveMutex()
3408 */
3409 static void winShmEnterMutex(void){
3410   sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
3411 }
3412 static void winShmLeaveMutex(void){
3413   sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
3414 }
3415 #ifndef NDEBUG
3416 static int winShmMutexHeld(void) {
3417   return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
3418 }
3419 #endif
3420 
3421 /*
3422 ** Object used to represent a single file opened and mmapped to provide
3423 ** shared memory.  When multiple threads all reference the same
3424 ** log-summary, each thread has its own winFile object, but they all
3425 ** point to a single instance of this object.  In other words, each
3426 ** log-summary is opened only once per process.
3427 **
3428 ** winShmMutexHeld() must be true when creating or destroying
3429 ** this object or while reading or writing the following fields:
3430 **
3431 **      nRef
3432 **      pNext
3433 **
3434 ** The following fields are read-only after the object is created:
3435 **
3436 **      fid
3437 **      zFilename
3438 **
3439 ** Either winShmNode.mutex must be held or winShmNode.nRef==0 and
3440 ** winShmMutexHeld() is true when reading or writing any other field
3441 ** in this structure.
3442 **
3443 */
3444 struct winShmNode {
3445   sqlite3_mutex *mutex;      /* Mutex to access this object */
3446   char *zFilename;           /* Name of the file */
3447   winFile hFile;             /* File handle from winOpen */
3448 
3449   int szRegion;              /* Size of shared-memory regions */
3450   int nRegion;               /* Size of array apRegion */
3451   struct ShmRegion {
3452     HANDLE hMap;             /* File handle from CreateFileMapping */
3453     void *pMap;
3454   } *aRegion;
3455   DWORD lastErrno;           /* The Windows errno from the last I/O error */
3456 
3457   int nRef;                  /* Number of winShm objects pointing to this */
3458   winShm *pFirst;            /* All winShm objects pointing to this */
3459   winShmNode *pNext;         /* Next in list of all winShmNode objects */
3460 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3461   u8 nextShmId;              /* Next available winShm.id value */
3462 #endif
3463 };
3464 
3465 /*
3466 ** A global array of all winShmNode objects.
3467 **
3468 ** The winShmMutexHeld() must be true while reading or writing this list.
3469 */
3470 static winShmNode *winShmNodeList = 0;
3471 
3472 /*
3473 ** Structure used internally by this VFS to record the state of an
3474 ** open shared memory connection.
3475 **
3476 ** The following fields are initialized when this object is created and
3477 ** are read-only thereafter:
3478 **
3479 **    winShm.pShmNode
3480 **    winShm.id
3481 **
3482 ** All other fields are read/write.  The winShm.pShmNode->mutex must be held
3483 ** while accessing any read/write fields.
3484 */
3485 struct winShm {
3486   winShmNode *pShmNode;      /* The underlying winShmNode object */
3487   winShm *pNext;             /* Next winShm with the same winShmNode */
3488   u8 hasMutex;               /* True if holding the winShmNode mutex */
3489   u16 sharedMask;            /* Mask of shared locks held */
3490   u16 exclMask;              /* Mask of exclusive locks held */
3491 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3492   u8 id;                     /* Id of this connection with its winShmNode */
3493 #endif
3494 };
3495 
3496 /*
3497 ** Constants used for locking
3498 */
3499 #define WIN_SHM_BASE   ((22+SQLITE_SHM_NLOCK)*4)        /* first lock byte */
3500 #define WIN_SHM_DMS    (WIN_SHM_BASE+SQLITE_SHM_NLOCK)  /* deadman switch */
3501 
3502 /*
3503 ** Apply advisory locks for all n bytes beginning at ofst.
3504 */
3505 #define _SHM_UNLCK  1
3506 #define _SHM_RDLCK  2
3507 #define _SHM_WRLCK  3
3508 static int winShmSystemLock(
3509   winShmNode *pFile,    /* Apply locks to this open shared-memory segment */
3510   int lockType,         /* _SHM_UNLCK, _SHM_RDLCK, or _SHM_WRLCK */
3511   int ofst,             /* Offset to first byte to be locked/unlocked */
3512   int nByte             /* Number of bytes to lock or unlock */
3513 ){
3514   int rc = 0;           /* Result code form Lock/UnlockFileEx() */
3515 
3516   /* Access to the winShmNode object is serialized by the caller */
3517   assert( sqlite3_mutex_held(pFile->mutex) || pFile->nRef==0 );
3518 
3519   OSTRACE(("SHM-LOCK file=%p, lock=%d, offset=%d, size=%d\n",
3520            pFile->hFile.h, lockType, ofst, nByte));
3521 
3522   /* Release/Acquire the system-level lock */
3523   if( lockType==_SHM_UNLCK ){
3524     rc = winUnlockFile(&pFile->hFile.h, ofst, 0, nByte, 0);
3525   }else{
3526     /* Initialize the locking parameters */
3527     DWORD dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
3528     if( lockType == _SHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
3529     rc = winLockFile(&pFile->hFile.h, dwFlags, ofst, 0, nByte, 0);
3530   }
3531 
3532   if( rc!= 0 ){
3533     rc = SQLITE_OK;
3534   }else{
3535     pFile->lastErrno =  osGetLastError();
3536     rc = SQLITE_BUSY;
3537   }
3538 
3539   OSTRACE(("SHM-LOCK file=%p, func=%s, errno=%lu, rc=%s\n",
3540            pFile->hFile.h, (lockType == _SHM_UNLCK) ? "winUnlockFile" :
3541            "winLockFile", pFile->lastErrno, sqlite3ErrName(rc)));
3542 
3543   return rc;
3544 }
3545 
3546 /* Forward references to VFS methods */
3547 static int winOpen(sqlite3_vfs*,const char*,sqlite3_file*,int,int*);
3548 static int winDelete(sqlite3_vfs *,const char*,int);
3549 
3550 /*
3551 ** Purge the winShmNodeList list of all entries with winShmNode.nRef==0.
3552 **
3553 ** This is not a VFS shared-memory method; it is a utility function called
3554 ** by VFS shared-memory methods.
3555 */
3556 static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
3557   winShmNode **pp;
3558   winShmNode *p;
3559   assert( winShmMutexHeld() );
3560   OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
3561            osGetCurrentProcessId(), deleteFlag));
3562   pp = &winShmNodeList;
3563   while( (p = *pp)!=0 ){
3564     if( p->nRef==0 ){
3565       int i;
3566       if( p->mutex ){ sqlite3_mutex_free(p->mutex); }
3567       for(i=0; i<p->nRegion; i++){
3568         BOOL bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
3569         OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
3570                  osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
3571         UNUSED_VARIABLE_VALUE(bRc);
3572         bRc = osCloseHandle(p->aRegion[i].hMap);
3573         OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
3574                  osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
3575         UNUSED_VARIABLE_VALUE(bRc);
3576       }
3577       if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
3578         SimulateIOErrorBenign(1);
3579         winClose((sqlite3_file *)&p->hFile);
3580         SimulateIOErrorBenign(0);
3581       }
3582       if( deleteFlag ){
3583         SimulateIOErrorBenign(1);
3584         sqlite3BeginBenignMalloc();
3585         winDelete(pVfs, p->zFilename, 0);
3586         sqlite3EndBenignMalloc();
3587         SimulateIOErrorBenign(0);
3588       }
3589       *pp = p->pNext;
3590       sqlite3_free(p->aRegion);
3591       sqlite3_free(p);
3592     }else{
3593       pp = &p->pNext;
3594     }
3595   }
3596 }
3597 
3598 /*
3599 ** Open the shared-memory area associated with database file pDbFd.
3600 **
3601 ** When opening a new shared-memory file, if no other instances of that
3602 ** file are currently open, in this process or in other processes, then
3603 ** the file must be truncated to zero length or have its header cleared.
3604 */
3605 static int winOpenSharedMemory(winFile *pDbFd){
3606   struct winShm *p;                  /* The connection to be opened */
3607   struct winShmNode *pShmNode = 0;   /* The underlying mmapped file */
3608   int rc;                            /* Result code */
3609   struct winShmNode *pNew;           /* Newly allocated winShmNode */
3610   int nName;                         /* Size of zName in bytes */
3611 
3612   assert( pDbFd->pShm==0 );    /* Not previously opened */
3613 
3614   /* Allocate space for the new sqlite3_shm object.  Also speculatively
3615   ** allocate space for a new winShmNode and filename.
3616   */
3617   p = sqlite3MallocZero( sizeof(*p) );
3618   if( p==0 ) return SQLITE_IOERR_NOMEM_BKPT;
3619   nName = sqlite3Strlen30(pDbFd->zPath);
3620   pNew = sqlite3MallocZero( sizeof(*pShmNode) + nName + 17 );
3621   if( pNew==0 ){
3622     sqlite3_free(p);
3623     return SQLITE_IOERR_NOMEM_BKPT;
3624   }
3625   pNew->zFilename = (char*)&pNew[1];
3626   sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
3627   sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename);
3628 
3629   /* Look to see if there is an existing winShmNode that can be used.
3630   ** If no matching winShmNode currently exists, create a new one.
3631   */
3632   winShmEnterMutex();
3633   for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){
3634     /* TBD need to come up with better match here.  Perhaps
3635     ** use FILE_ID_BOTH_DIR_INFO Structure.
3636     */
3637     if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break;
3638   }
3639   if( pShmNode ){
3640     sqlite3_free(pNew);
3641   }else{
3642     pShmNode = pNew;
3643     pNew = 0;
3644     ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE;
3645     pShmNode->pNext = winShmNodeList;
3646     winShmNodeList = pShmNode;
3647 
3648     pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
3649     if( pShmNode->mutex==0 ){
3650       rc = SQLITE_IOERR_NOMEM_BKPT;
3651       goto shm_open_err;
3652     }
3653 
3654     rc = winOpen(pDbFd->pVfs,
3655                  pShmNode->zFilename,             /* Name of the file (UTF-8) */
3656                  (sqlite3_file*)&pShmNode->hFile,  /* File handle here */
3657                  SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE,
3658                  0);
3659     if( SQLITE_OK!=rc ){
3660       goto shm_open_err;
3661     }
3662 
3663     /* Check to see if another process is holding the dead-man switch.
3664     ** If not, truncate the file to zero length.
3665     */
3666     if( winShmSystemLock(pShmNode, _SHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){
3667       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0);
3668       if( rc!=SQLITE_OK ){
3669         rc = winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
3670                          "winOpenShm", pDbFd->zPath);
3671       }
3672     }
3673     if( rc==SQLITE_OK ){
3674       winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
3675       rc = winShmSystemLock(pShmNode, _SHM_RDLCK, WIN_SHM_DMS, 1);
3676     }
3677     if( rc ) goto shm_open_err;
3678   }
3679 
3680   /* Make the new connection a child of the winShmNode */
3681   p->pShmNode = pShmNode;
3682 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
3683   p->id = pShmNode->nextShmId++;
3684 #endif
3685   pShmNode->nRef++;
3686   pDbFd->pShm = p;
3687   winShmLeaveMutex();
3688 
3689   /* The reference count on pShmNode has already been incremented under
3690   ** the cover of the winShmEnterMutex() mutex and the pointer from the
3691   ** new (struct winShm) object to the pShmNode has been set. All that is
3692   ** left to do is to link the new object into the linked list starting
3693   ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex
3694   ** mutex.
3695   */
3696   sqlite3_mutex_enter(pShmNode->mutex);
3697   p->pNext = pShmNode->pFirst;
3698   pShmNode->pFirst = p;
3699   sqlite3_mutex_leave(pShmNode->mutex);
3700   return SQLITE_OK;
3701 
3702   /* Jump here on any error */
3703 shm_open_err:
3704   winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
3705   winShmPurge(pDbFd->pVfs, 0);      /* This call frees pShmNode if required */
3706   sqlite3_free(p);
3707   sqlite3_free(pNew);
3708   winShmLeaveMutex();
3709   return rc;
3710 }
3711 
3712 /*
3713 ** Close a connection to shared-memory.  Delete the underlying
3714 ** storage if deleteFlag is true.
3715 */
3716 static int winShmUnmap(
3717   sqlite3_file *fd,          /* Database holding shared memory */
3718   int deleteFlag             /* Delete after closing if true */
3719 ){
3720   winFile *pDbFd;       /* Database holding shared-memory */
3721   winShm *p;            /* The connection to be closed */
3722   winShmNode *pShmNode; /* The underlying shared-memory file */
3723   winShm **pp;          /* For looping over sibling connections */
3724 
3725   pDbFd = (winFile*)fd;
3726   p = pDbFd->pShm;
3727   if( p==0 ) return SQLITE_OK;
3728   pShmNode = p->pShmNode;
3729 
3730   /* Remove connection p from the set of connections associated
3731   ** with pShmNode */
3732   sqlite3_mutex_enter(pShmNode->mutex);
3733   for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
3734   *pp = p->pNext;
3735 
3736   /* Free the connection p */
3737   sqlite3_free(p);
3738   pDbFd->pShm = 0;
3739   sqlite3_mutex_leave(pShmNode->mutex);
3740 
3741   /* If pShmNode->nRef has reached 0, then close the underlying
3742   ** shared-memory file, too */
3743   winShmEnterMutex();
3744   assert( pShmNode->nRef>0 );
3745   pShmNode->nRef--;
3746   if( pShmNode->nRef==0 ){
3747     winShmPurge(pDbFd->pVfs, deleteFlag);
3748   }
3749   winShmLeaveMutex();
3750 
3751   return SQLITE_OK;
3752 }
3753 
3754 /*
3755 ** Change the lock state for a shared-memory segment.
3756 */
3757 static int winShmLock(
3758   sqlite3_file *fd,          /* Database file holding the shared memory */
3759   int ofst,                  /* First lock to acquire or release */
3760   int n,                     /* Number of locks to acquire or release */
3761   int flags                  /* What to do with the lock */
3762 ){
3763   winFile *pDbFd = (winFile*)fd;        /* Connection holding shared memory */
3764   winShm *p = pDbFd->pShm;              /* The shared memory being locked */
3765   winShm *pX;                           /* For looping over all siblings */
3766   winShmNode *pShmNode = p->pShmNode;
3767   int rc = SQLITE_OK;                   /* Result code */
3768   u16 mask;                             /* Mask of locks to take or release */
3769 
3770   assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
3771   assert( n>=1 );
3772   assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
3773        || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
3774        || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
3775        || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
3776   assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
3777 
3778   mask = (u16)((1U<<(ofst+n)) - (1U<<ofst));
3779   assert( n>1 || mask==(1<<ofst) );
3780   sqlite3_mutex_enter(pShmNode->mutex);
3781   if( flags & SQLITE_SHM_UNLOCK ){
3782     u16 allMask = 0; /* Mask of locks held by siblings */
3783 
3784     /* See if any siblings hold this same lock */
3785     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
3786       if( pX==p ) continue;
3787       assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
3788       allMask |= pX->sharedMask;
3789     }
3790 
3791     /* Unlock the system-level locks */
3792     if( (mask & allMask)==0 ){
3793       rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
3794     }else{
3795       rc = SQLITE_OK;
3796     }
3797 
3798     /* Undo the local locks */
3799     if( rc==SQLITE_OK ){
3800       p->exclMask &= ~mask;
3801       p->sharedMask &= ~mask;
3802     }
3803   }else if( flags & SQLITE_SHM_SHARED ){
3804     u16 allShared = 0;  /* Union of locks held by connections other than "p" */
3805 
3806     /* Find out which shared locks are already held by sibling connections.
3807     ** If any sibling already holds an exclusive lock, go ahead and return
3808     ** SQLITE_BUSY.
3809     */
3810     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
3811       if( (pX->exclMask & mask)!=0 ){
3812         rc = SQLITE_BUSY;
3813         break;
3814       }
3815       allShared |= pX->sharedMask;
3816     }
3817 
3818     /* Get shared locks at the system level, if necessary */
3819     if( rc==SQLITE_OK ){
3820       if( (allShared & mask)==0 ){
3821         rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
3822       }else{
3823         rc = SQLITE_OK;
3824       }
3825     }
3826 
3827     /* Get the local shared locks */
3828     if( rc==SQLITE_OK ){
3829       p->sharedMask |= mask;
3830     }
3831   }else{
3832     /* Make sure no sibling connections hold locks that will block this
3833     ** lock.  If any do, return SQLITE_BUSY right away.
3834     */
3835     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
3836       if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
3837         rc = SQLITE_BUSY;
3838         break;
3839       }
3840     }
3841 
3842     /* Get the exclusive locks at the system level.  Then if successful
3843     ** also mark the local connection as being locked.
3844     */
3845     if( rc==SQLITE_OK ){
3846       rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
3847       if( rc==SQLITE_OK ){
3848         assert( (p->sharedMask & mask)==0 );
3849         p->exclMask |= mask;
3850       }
3851     }
3852   }
3853   sqlite3_mutex_leave(pShmNode->mutex);
3854   OSTRACE(("SHM-LOCK pid=%lu, id=%d, sharedMask=%03x, exclMask=%03x, rc=%s\n",
3855            osGetCurrentProcessId(), p->id, p->sharedMask, p->exclMask,
3856            sqlite3ErrName(rc)));
3857   return rc;
3858 }
3859 
3860 /*
3861 ** Implement a memory barrier or memory fence on shared memory.
3862 **
3863 ** All loads and stores begun before the barrier must complete before
3864 ** any load or store begun after the barrier.
3865 */
3866 static void winShmBarrier(
3867   sqlite3_file *fd          /* Database holding the shared memory */
3868 ){
3869   UNUSED_PARAMETER(fd);
3870   sqlite3MemoryBarrier();   /* compiler-defined memory barrier */
3871   winShmEnterMutex();       /* Also mutex, for redundancy */
3872   winShmLeaveMutex();
3873 }
3874 
3875 /*
3876 ** This function is called to obtain a pointer to region iRegion of the
3877 ** shared-memory associated with the database file fd. Shared-memory regions
3878 ** are numbered starting from zero. Each shared-memory region is szRegion
3879 ** bytes in size.
3880 **
3881 ** If an error occurs, an error code is returned and *pp is set to NULL.
3882 **
3883 ** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
3884 ** region has not been allocated (by any client, including one running in a
3885 ** separate process), then *pp is set to NULL and SQLITE_OK returned. If
3886 ** isWrite is non-zero and the requested shared-memory region has not yet
3887 ** been allocated, it is allocated by this function.
3888 **
3889 ** If the shared-memory region has already been allocated or is allocated by
3890 ** this call as described above, then it is mapped into this processes
3891 ** address space (if it is not already), *pp is set to point to the mapped
3892 ** memory and SQLITE_OK returned.
3893 */
3894 static int winShmMap(
3895   sqlite3_file *fd,               /* Handle open on database file */
3896   int iRegion,                    /* Region to retrieve */
3897   int szRegion,                   /* Size of regions */
3898   int isWrite,                    /* True to extend file if necessary */
3899   void volatile **pp              /* OUT: Mapped memory */
3900 ){
3901   winFile *pDbFd = (winFile*)fd;
3902   winShm *pShm = pDbFd->pShm;
3903   winShmNode *pShmNode;
3904   int rc = SQLITE_OK;
3905 
3906   if( !pShm ){
3907     rc = winOpenSharedMemory(pDbFd);
3908     if( rc!=SQLITE_OK ) return rc;
3909     pShm = pDbFd->pShm;
3910   }
3911   pShmNode = pShm->pShmNode;
3912 
3913   sqlite3_mutex_enter(pShmNode->mutex);
3914   assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
3915 
3916   if( pShmNode->nRegion<=iRegion ){
3917     struct ShmRegion *apNew;           /* New aRegion[] array */
3918     int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
3919     sqlite3_int64 sz;                  /* Current size of wal-index file */
3920 
3921     pShmNode->szRegion = szRegion;
3922 
3923     /* The requested region is not mapped into this processes address space.
3924     ** Check to see if it has been allocated (i.e. if the wal-index file is
3925     ** large enough to contain the requested region).
3926     */
3927     rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
3928     if( rc!=SQLITE_OK ){
3929       rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
3930                        "winShmMap1", pDbFd->zPath);
3931       goto shmpage_out;
3932     }
3933 
3934     if( sz<nByte ){
3935       /* The requested memory region does not exist. If isWrite is set to
3936       ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
3937       **
3938       ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
3939       ** the requested memory region.
3940       */
3941       if( !isWrite ) goto shmpage_out;
3942       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
3943       if( rc!=SQLITE_OK ){
3944         rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
3945                          "winShmMap2", pDbFd->zPath);
3946         goto shmpage_out;
3947       }
3948     }
3949 
3950     /* Map the requested memory region into this processes address space. */
3951     apNew = (struct ShmRegion *)sqlite3_realloc64(
3952         pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
3953     );
3954     if( !apNew ){
3955       rc = SQLITE_IOERR_NOMEM_BKPT;
3956       goto shmpage_out;
3957     }
3958     pShmNode->aRegion = apNew;
3959 
3960     while( pShmNode->nRegion<=iRegion ){
3961       HANDLE hMap = NULL;         /* file-mapping handle */
3962       void *pMap = 0;             /* Mapped memory region */
3963 
3964 #if SQLITE_OS_WINRT
3965       hMap = osCreateFileMappingFromApp(pShmNode->hFile.h,
3966           NULL, PAGE_READWRITE, nByte, NULL
3967       );
3968 #elif defined(SQLITE_WIN32_HAS_WIDE)
3969       hMap = osCreateFileMappingW(pShmNode->hFile.h,
3970           NULL, PAGE_READWRITE, 0, nByte, NULL
3971       );
3972 #elif defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_CREATEFILEMAPPINGA
3973       hMap = osCreateFileMappingA(pShmNode->hFile.h,
3974           NULL, PAGE_READWRITE, 0, nByte, NULL
3975       );
3976 #endif
3977       OSTRACE(("SHM-MAP-CREATE pid=%lu, region=%d, size=%d, rc=%s\n",
3978                osGetCurrentProcessId(), pShmNode->nRegion, nByte,
3979                hMap ? "ok" : "failed"));
3980       if( hMap ){
3981         int iOffset = pShmNode->nRegion*szRegion;
3982         int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
3983 #if SQLITE_OS_WINRT
3984         pMap = osMapViewOfFileFromApp(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
3985             iOffset - iOffsetShift, szRegion + iOffsetShift
3986         );
3987 #else
3988         pMap = osMapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
3989             0, iOffset - iOffsetShift, szRegion + iOffsetShift
3990         );
3991 #endif
3992         OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
3993                  osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
3994                  szRegion, pMap ? "ok" : "failed"));
3995       }
3996       if( !pMap ){
3997         pShmNode->lastErrno = osGetLastError();
3998         rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
3999                          "winShmMap3", pDbFd->zPath);
4000         if( hMap ) osCloseHandle(hMap);
4001         goto shmpage_out;
4002       }
4003 
4004       pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
4005       pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
4006       pShmNode->nRegion++;
4007     }
4008   }
4009 
4010 shmpage_out:
4011   if( pShmNode->nRegion>iRegion ){
4012     int iOffset = iRegion*szRegion;
4013     int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
4014     char *p = (char *)pShmNode->aRegion[iRegion].pMap;
4015     *pp = (void *)&p[iOffsetShift];
4016   }else{
4017     *pp = 0;
4018   }
4019   sqlite3_mutex_leave(pShmNode->mutex);
4020   return rc;
4021 }
4022 
4023 #else
4024 # define winShmMap     0
4025 # define winShmLock    0
4026 # define winShmBarrier 0
4027 # define winShmUnmap   0
4028 #endif /* #ifndef SQLITE_OMIT_WAL */
4029 
4030 /*
4031 ** Cleans up the mapped region of the specified file, if any.
4032 */
4033 #if SQLITE_MAX_MMAP_SIZE>0
4034 static int winUnmapfile(winFile *pFile){
4035   assert( pFile!=0 );
4036   OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, pMapRegion=%p, "
4037            "mmapSize=%lld, mmapSizeActual=%lld, mmapSizeMax=%lld\n",
4038            osGetCurrentProcessId(), pFile, pFile->hMap, pFile->pMapRegion,
4039            pFile->mmapSize, pFile->mmapSizeActual, pFile->mmapSizeMax));
4040   if( pFile->pMapRegion ){
4041     if( !osUnmapViewOfFile(pFile->pMapRegion) ){
4042       pFile->lastErrno = osGetLastError();
4043       OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
4044                "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
4045                pFile->pMapRegion));
4046       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
4047                          "winUnmapfile1", pFile->zPath);
4048     }
4049     pFile->pMapRegion = 0;
4050     pFile->mmapSize = 0;
4051     pFile->mmapSizeActual = 0;
4052   }
4053   if( pFile->hMap!=NULL ){
4054     if( !osCloseHandle(pFile->hMap) ){
4055       pFile->lastErrno = osGetLastError();
4056       OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
4057                osGetCurrentProcessId(), pFile, pFile->hMap));
4058       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
4059                          "winUnmapfile2", pFile->zPath);
4060     }
4061     pFile->hMap = NULL;
4062   }
4063   OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
4064            osGetCurrentProcessId(), pFile));
4065   return SQLITE_OK;
4066 }
4067 
4068 /*
4069 ** Memory map or remap the file opened by file-descriptor pFd (if the file
4070 ** is already mapped, the existing mapping is replaced by the new). Or, if
4071 ** there already exists a mapping for this file, and there are still
4072 ** outstanding xFetch() references to it, this function is a no-op.
4073 **
4074 ** If parameter nByte is non-negative, then it is the requested size of
4075 ** the mapping to create. Otherwise, if nByte is less than zero, then the
4076 ** requested size is the size of the file on disk. The actual size of the
4077 ** created mapping is either the requested size or the value configured
4078 ** using SQLITE_FCNTL_MMAP_SIZE, whichever is smaller.
4079 **
4080 ** SQLITE_OK is returned if no error occurs (even if the mapping is not
4081 ** recreated as a result of outstanding references) or an SQLite error
4082 ** code otherwise.
4083 */
4084 static int winMapfile(winFile *pFd, sqlite3_int64 nByte){
4085   sqlite3_int64 nMap = nByte;
4086   int rc;
4087 
4088   assert( nMap>=0 || pFd->nFetchOut==0 );
4089   OSTRACE(("MAP-FILE pid=%lu, pFile=%p, size=%lld\n",
4090            osGetCurrentProcessId(), pFd, nByte));
4091 
4092   if( pFd->nFetchOut>0 ) return SQLITE_OK;
4093 
4094   if( nMap<0 ){
4095     rc = winFileSize((sqlite3_file*)pFd, &nMap);
4096     if( rc ){
4097       OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_IOERR_FSTAT\n",
4098                osGetCurrentProcessId(), pFd));
4099       return SQLITE_IOERR_FSTAT;
4100     }
4101   }
4102   if( nMap>pFd->mmapSizeMax ){
4103     nMap = pFd->mmapSizeMax;
4104   }
4105   nMap &= ~(sqlite3_int64)(winSysInfo.dwPageSize - 1);
4106 
4107   if( nMap==0 && pFd->mmapSize>0 ){
4108     winUnmapfile(pFd);
4109   }
4110   if( nMap!=pFd->mmapSize ){
4111     void *pNew = 0;
4112     DWORD protect = PAGE_READONLY;
4113     DWORD flags = FILE_MAP_READ;
4114 
4115     winUnmapfile(pFd);
4116 #ifdef SQLITE_MMAP_READWRITE
4117     if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
4118       protect = PAGE_READWRITE;
4119       flags |= FILE_MAP_WRITE;
4120     }
4121 #endif
4122 #if SQLITE_OS_WINRT
4123     pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
4124 #elif defined(SQLITE_WIN32_HAS_WIDE)
4125     pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
4126                                 (DWORD)((nMap>>32) & 0xffffffff),
4127                                 (DWORD)(nMap & 0xffffffff), NULL);
4128 #elif defined(SQLITE_WIN32_HAS_ANSI) && SQLITE_WIN32_CREATEFILEMAPPINGA
4129     pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
4130                                 (DWORD)((nMap>>32) & 0xffffffff),
4131                                 (DWORD)(nMap & 0xffffffff), NULL);
4132 #endif
4133     if( pFd->hMap==NULL ){
4134       pFd->lastErrno = osGetLastError();
4135       rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
4136                        "winMapfile1", pFd->zPath);
4137       /* Log the error, but continue normal operation using xRead/xWrite */
4138       OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=%s\n",
4139                osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
4140       return SQLITE_OK;
4141     }
4142     assert( (nMap % winSysInfo.dwPageSize)==0 );
4143     assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
4144 #if SQLITE_OS_WINRT
4145     pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
4146 #else
4147     pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
4148 #endif
4149     if( pNew==NULL ){
4150       osCloseHandle(pFd->hMap);
4151       pFd->hMap = NULL;
4152       pFd->lastErrno = osGetLastError();
4153       rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
4154                        "winMapfile2", pFd->zPath);
4155       /* Log the error, but continue normal operation using xRead/xWrite */
4156       OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=%s\n",
4157                osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
4158       return SQLITE_OK;
4159     }
4160     pFd->pMapRegion = pNew;
4161     pFd->mmapSize = nMap;
4162     pFd->mmapSizeActual = nMap;
4163   }
4164 
4165   OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
4166            osGetCurrentProcessId(), pFd));
4167   return SQLITE_OK;
4168 }
4169 #endif /* SQLITE_MAX_MMAP_SIZE>0 */
4170 
4171 /*
4172 ** If possible, return a pointer to a mapping of file fd starting at offset
4173 ** iOff. The mapping must be valid for at least nAmt bytes.
4174 **
4175 ** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
4176 ** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
4177 ** Finally, if an error does occur, return an SQLite error code. The final
4178 ** value of *pp is undefined in this case.
4179 **
4180 ** If this function does return a pointer, the caller must eventually
4181 ** release the reference by calling winUnfetch().
4182 */
4183 static int winFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
4184 #if SQLITE_MAX_MMAP_SIZE>0
4185   winFile *pFd = (winFile*)fd;   /* The underlying database file */
4186 #endif
4187   *pp = 0;
4188 
4189   OSTRACE(("FETCH pid=%lu, pFile=%p, offset=%lld, amount=%d, pp=%p\n",
4190            osGetCurrentProcessId(), fd, iOff, nAmt, pp));
4191 
4192 #if SQLITE_MAX_MMAP_SIZE>0
4193   if( pFd->mmapSizeMax>0 ){
4194     if( pFd->pMapRegion==0 ){
4195       int rc = winMapfile(pFd, -1);
4196       if( rc!=SQLITE_OK ){
4197         OSTRACE(("FETCH pid=%lu, pFile=%p, rc=%s\n",
4198                  osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
4199         return rc;
4200       }
4201     }
4202     if( pFd->mmapSize >= iOff+nAmt ){
4203       *pp = &((u8 *)pFd->pMapRegion)[iOff];
4204       pFd->nFetchOut++;
4205     }
4206   }
4207 #endif
4208 
4209   OSTRACE(("FETCH pid=%lu, pFile=%p, pp=%p, *pp=%p, rc=SQLITE_OK\n",
4210            osGetCurrentProcessId(), fd, pp, *pp));
4211   return SQLITE_OK;
4212 }
4213 
4214 /*
4215 ** If the third argument is non-NULL, then this function releases a
4216 ** reference obtained by an earlier call to winFetch(). The second
4217 ** argument passed to this function must be the same as the corresponding
4218 ** argument that was passed to the winFetch() invocation.
4219 **
4220 ** Or, if the third argument is NULL, then this function is being called
4221 ** to inform the VFS layer that, according to POSIX, any existing mapping
4222 ** may now be invalid and should be unmapped.
4223 */
4224 static int winUnfetch(sqlite3_file *fd, i64 iOff, void *p){
4225 #if SQLITE_MAX_MMAP_SIZE>0
4226   winFile *pFd = (winFile*)fd;   /* The underlying database file */
4227 
4228   /* If p==0 (unmap the entire file) then there must be no outstanding
4229   ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
4230   ** then there must be at least one outstanding.  */
4231   assert( (p==0)==(pFd->nFetchOut==0) );
4232 
4233   /* If p!=0, it must match the iOff value. */
4234   assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
4235 
4236   OSTRACE(("UNFETCH pid=%lu, pFile=%p, offset=%lld, p=%p\n",
4237            osGetCurrentProcessId(), pFd, iOff, p));
4238 
4239   if( p ){
4240     pFd->nFetchOut--;
4241   }else{
4242     /* FIXME:  If Windows truly always prevents truncating or deleting a
4243     ** file while a mapping is held, then the following winUnmapfile() call
4244     ** is unnecessary can be omitted - potentially improving
4245     ** performance.  */
4246     winUnmapfile(pFd);
4247   }
4248 
4249   assert( pFd->nFetchOut>=0 );
4250 #endif
4251 
4252   OSTRACE(("UNFETCH pid=%lu, pFile=%p, rc=SQLITE_OK\n",
4253            osGetCurrentProcessId(), fd));
4254   return SQLITE_OK;
4255 }
4256 
4257 /*
4258 ** Here ends the implementation of all sqlite3_file methods.
4259 **
4260 ********************** End sqlite3_file Methods *******************************
4261 ******************************************************************************/
4262 
4263 /*
4264 ** This vector defines all the methods that can operate on an
4265 ** sqlite3_file for win32.
4266 */
4267 static const sqlite3_io_methods winIoMethod = {
4268   3,                              /* iVersion */
4269   winClose,                       /* xClose */
4270   winRead,                        /* xRead */
4271   winWrite,                       /* xWrite */
4272   winTruncate,                    /* xTruncate */
4273   winSync,                        /* xSync */
4274   winFileSize,                    /* xFileSize */
4275   winLock,                        /* xLock */
4276   winUnlock,                      /* xUnlock */
4277   winCheckReservedLock,           /* xCheckReservedLock */
4278   winFileControl,                 /* xFileControl */
4279   winSectorSize,                  /* xSectorSize */
4280   winDeviceCharacteristics,       /* xDeviceCharacteristics */
4281   winShmMap,                      /* xShmMap */
4282   winShmLock,                     /* xShmLock */
4283   winShmBarrier,                  /* xShmBarrier */
4284   winShmUnmap,                    /* xShmUnmap */
4285   winFetch,                       /* xFetch */
4286   winUnfetch                      /* xUnfetch */
4287 };
4288 
4289 /****************************************************************************
4290 **************************** sqlite3_vfs methods ****************************
4291 **
4292 ** This division contains the implementation of methods on the
4293 ** sqlite3_vfs object.
4294 */
4295 
4296 #if defined(__CYGWIN__)
4297 /*
4298 ** Convert a filename from whatever the underlying operating system
4299 ** supports for filenames into UTF-8.  Space to hold the result is
4300 ** obtained from malloc and must be freed by the calling function.
4301 */
4302 static char *winConvertToUtf8Filename(const void *zFilename){
4303   char *zConverted = 0;
4304   if( osIsNT() ){
4305     zConverted = winUnicodeToUtf8(zFilename);
4306   }
4307 #ifdef SQLITE_WIN32_HAS_ANSI
4308   else{
4309     zConverted = sqlite3_win32_mbcs_to_utf8(zFilename);
4310   }
4311 #endif
4312   /* caller will handle out of memory */
4313   return zConverted;
4314 }
4315 #endif
4316 
4317 /*
4318 ** Convert a UTF-8 filename into whatever form the underlying
4319 ** operating system wants filenames in.  Space to hold the result
4320 ** is obtained from malloc and must be freed by the calling
4321 ** function.
4322 */
4323 static void *winConvertFromUtf8Filename(const char *zFilename){
4324   void *zConverted = 0;
4325   if( osIsNT() ){
4326     zConverted = winUtf8ToUnicode(zFilename);
4327   }
4328 #ifdef SQLITE_WIN32_HAS_ANSI
4329   else{
4330     zConverted = sqlite3_win32_utf8_to_mbcs(zFilename);
4331   }
4332 #endif
4333   /* caller will handle out of memory */
4334   return zConverted;
4335 }
4336 
4337 /*
4338 ** This function returns non-zero if the specified UTF-8 string buffer
4339 ** ends with a directory separator character or one was successfully
4340 ** added to it.
4341 */
4342 static int winMakeEndInDirSep(int nBuf, char *zBuf){
4343   if( zBuf ){
4344     int nLen = sqlite3Strlen30(zBuf);
4345     if( nLen>0 ){
4346       if( winIsDirSep(zBuf[nLen-1]) ){
4347         return 1;
4348       }else if( nLen+1<nBuf ){
4349         zBuf[nLen] = winGetDirSep();
4350         zBuf[nLen+1] = '\0';
4351         return 1;
4352       }
4353     }
4354   }
4355   return 0;
4356 }
4357 
4358 /*
4359 ** Create a temporary file name and store the resulting pointer into pzBuf.
4360 ** The pointer returned in pzBuf must be freed via sqlite3_free().
4361 */
4362 static int winGetTempname(sqlite3_vfs *pVfs, char **pzBuf){
4363   static char zChars[] =
4364     "abcdefghijklmnopqrstuvwxyz"
4365     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
4366     "0123456789";
4367   size_t i, j;
4368   int nPre = sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX);
4369   int nMax, nBuf, nDir, nLen;
4370   char *zBuf;
4371 
4372   /* It's odd to simulate an io-error here, but really this is just
4373   ** using the io-error infrastructure to test that SQLite handles this
4374   ** function failing.
4375   */
4376   SimulateIOError( return SQLITE_IOERR );
4377 
4378   /* Allocate a temporary buffer to store the fully qualified file
4379   ** name for the temporary file.  If this fails, we cannot continue.
4380   */
4381   nMax = pVfs->mxPathname; nBuf = nMax + 2;
4382   zBuf = sqlite3MallocZero( nBuf );
4383   if( !zBuf ){
4384     OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4385     return SQLITE_IOERR_NOMEM_BKPT;
4386   }
4387 
4388   /* Figure out the effective temporary directory.  First, check if one
4389   ** has been explicitly set by the application; otherwise, use the one
4390   ** configured by the operating system.
4391   */
4392   nDir = nMax - (nPre + 15);
4393   assert( nDir>0 );
4394   if( sqlite3_temp_directory ){
4395     int nDirLen = sqlite3Strlen30(sqlite3_temp_directory);
4396     if( nDirLen>0 ){
4397       if( !winIsDirSep(sqlite3_temp_directory[nDirLen-1]) ){
4398         nDirLen++;
4399       }
4400       if( nDirLen>nDir ){
4401         sqlite3_free(zBuf);
4402         OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4403         return winLogError(SQLITE_ERROR, 0, "winGetTempname1", 0);
4404       }
4405       sqlite3_snprintf(nMax, zBuf, "%s", sqlite3_temp_directory);
4406     }
4407   }
4408 #if defined(__CYGWIN__)
4409   else{
4410     static const char *azDirs[] = {
4411        0, /* getenv("SQLITE_TMPDIR") */
4412        0, /* getenv("TMPDIR") */
4413        0, /* getenv("TMP") */
4414        0, /* getenv("TEMP") */
4415        0, /* getenv("USERPROFILE") */
4416        "/var/tmp",
4417        "/usr/tmp",
4418        "/tmp",
4419        ".",
4420        0        /* List terminator */
4421     };
4422     unsigned int i;
4423     const char *zDir = 0;
4424 
4425     if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
4426     if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
4427     if( !azDirs[2] ) azDirs[2] = getenv("TMP");
4428     if( !azDirs[3] ) azDirs[3] = getenv("TEMP");
4429     if( !azDirs[4] ) azDirs[4] = getenv("USERPROFILE");
4430     for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
4431       void *zConverted;
4432       if( zDir==0 ) continue;
4433       /* If the path starts with a drive letter followed by the colon
4434       ** character, assume it is already a native Win32 path; otherwise,
4435       ** it must be converted to a native Win32 path via the Cygwin API
4436       ** prior to using it.
4437       */
4438       if( winIsDriveLetterAndColon(zDir) ){
4439         zConverted = winConvertFromUtf8Filename(zDir);
4440         if( !zConverted ){
4441           sqlite3_free(zBuf);
4442           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4443           return SQLITE_IOERR_NOMEM_BKPT;
4444         }
4445         if( winIsDir(zConverted) ){
4446           sqlite3_snprintf(nMax, zBuf, "%s", zDir);
4447           sqlite3_free(zConverted);
4448           break;
4449         }
4450         sqlite3_free(zConverted);
4451       }else{
4452         zConverted = sqlite3MallocZero( nMax+1 );
4453         if( !zConverted ){
4454           sqlite3_free(zBuf);
4455           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4456           return SQLITE_IOERR_NOMEM_BKPT;
4457         }
4458         if( cygwin_conv_path(
4459                 osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A, zDir,
4460                 zConverted, nMax+1)<0 ){
4461           sqlite3_free(zConverted);
4462           sqlite3_free(zBuf);
4463           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_CONVPATH\n"));
4464           return winLogError(SQLITE_IOERR_CONVPATH, (DWORD)errno,
4465                              "winGetTempname2", zDir);
4466         }
4467         if( winIsDir(zConverted) ){
4468           /* At this point, we know the candidate directory exists and should
4469           ** be used.  However, we may need to convert the string containing
4470           ** its name into UTF-8 (i.e. if it is UTF-16 right now).
4471           */
4472           char *zUtf8 = winConvertToUtf8Filename(zConverted);
4473           if( !zUtf8 ){
4474             sqlite3_free(zConverted);
4475             sqlite3_free(zBuf);
4476             OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4477             return SQLITE_IOERR_NOMEM_BKPT;
4478           }
4479           sqlite3_snprintf(nMax, zBuf, "%s", zUtf8);
4480           sqlite3_free(zUtf8);
4481           sqlite3_free(zConverted);
4482           break;
4483         }
4484         sqlite3_free(zConverted);
4485       }
4486     }
4487   }
4488 #elif !SQLITE_OS_WINRT && !defined(__CYGWIN__)
4489   else if( osIsNT() ){
4490     char *zMulti;
4491     LPWSTR zWidePath = sqlite3MallocZero( nMax*sizeof(WCHAR) );
4492     if( !zWidePath ){
4493       sqlite3_free(zBuf);
4494       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4495       return SQLITE_IOERR_NOMEM_BKPT;
4496     }
4497     if( osGetTempPathW(nMax, zWidePath)==0 ){
4498       sqlite3_free(zWidePath);
4499       sqlite3_free(zBuf);
4500       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
4501       return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
4502                          "winGetTempname2", 0);
4503     }
4504     zMulti = winUnicodeToUtf8(zWidePath);
4505     if( zMulti ){
4506       sqlite3_snprintf(nMax, zBuf, "%s", zMulti);
4507       sqlite3_free(zMulti);
4508       sqlite3_free(zWidePath);
4509     }else{
4510       sqlite3_free(zWidePath);
4511       sqlite3_free(zBuf);
4512       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4513       return SQLITE_IOERR_NOMEM_BKPT;
4514     }
4515   }
4516 #ifdef SQLITE_WIN32_HAS_ANSI
4517   else{
4518     char *zUtf8;
4519     char *zMbcsPath = sqlite3MallocZero( nMax );
4520     if( !zMbcsPath ){
4521       sqlite3_free(zBuf);
4522       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4523       return SQLITE_IOERR_NOMEM_BKPT;
4524     }
4525     if( osGetTempPathA(nMax, zMbcsPath)==0 ){
4526       sqlite3_free(zBuf);
4527       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
4528       return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
4529                          "winGetTempname3", 0);
4530     }
4531     zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath);
4532     if( zUtf8 ){
4533       sqlite3_snprintf(nMax, zBuf, "%s", zUtf8);
4534       sqlite3_free(zUtf8);
4535     }else{
4536       sqlite3_free(zBuf);
4537       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4538       return SQLITE_IOERR_NOMEM_BKPT;
4539     }
4540   }
4541 #endif /* SQLITE_WIN32_HAS_ANSI */
4542 #endif /* !SQLITE_OS_WINRT */
4543 
4544   /*
4545   ** Check to make sure the temporary directory ends with an appropriate
4546   ** separator.  If it does not and there is not enough space left to add
4547   ** one, fail.
4548   */
4549   if( !winMakeEndInDirSep(nDir+1, zBuf) ){
4550     sqlite3_free(zBuf);
4551     OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4552     return winLogError(SQLITE_ERROR, 0, "winGetTempname4", 0);
4553   }
4554 
4555   /*
4556   ** Check that the output buffer is large enough for the temporary file
4557   ** name in the following format:
4558   **
4559   **   "<temporary_directory>/etilqs_XXXXXXXXXXXXXXX\0\0"
4560   **
4561   ** If not, return SQLITE_ERROR.  The number 17 is used here in order to
4562   ** account for the space used by the 15 character random suffix and the
4563   ** two trailing NUL characters.  The final directory separator character
4564   ** has already added if it was not already present.
4565   */
4566   nLen = sqlite3Strlen30(zBuf);
4567   if( (nLen + nPre + 17) > nBuf ){
4568     sqlite3_free(zBuf);
4569     OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4570     return winLogError(SQLITE_ERROR, 0, "winGetTempname5", 0);
4571   }
4572 
4573   sqlite3_snprintf(nBuf-16-nLen, zBuf+nLen, SQLITE_TEMP_FILE_PREFIX);
4574 
4575   j = sqlite3Strlen30(zBuf);
4576   sqlite3_randomness(15, &zBuf[j]);
4577   for(i=0; i<15; i++, j++){
4578     zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
4579   }
4580   zBuf[j] = 0;
4581   zBuf[j+1] = 0;
4582   *pzBuf = zBuf;
4583 
4584   OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
4585   return SQLITE_OK;
4586 }
4587 
4588 /*
4589 ** Return TRUE if the named file is really a directory.  Return false if
4590 ** it is something other than a directory, or if there is any kind of memory
4591 ** allocation failure.
4592 */
4593 static int winIsDir(const void *zConverted){
4594   DWORD attr;
4595   int rc = 0;
4596   DWORD lastErrno;
4597 
4598   if( osIsNT() ){
4599     int cnt = 0;
4600     WIN32_FILE_ATTRIBUTE_DATA sAttrData;
4601     memset(&sAttrData, 0, sizeof(sAttrData));
4602     while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
4603                              GetFileExInfoStandard,
4604                              &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
4605     if( !rc ){
4606       return 0; /* Invalid name? */
4607     }
4608     attr = sAttrData.dwFileAttributes;
4609 #if SQLITE_OS_WINCE==0
4610   }else{
4611     attr = osGetFileAttributesA((char*)zConverted);
4612 #endif
4613   }
4614   return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
4615 }
4616 
4617 /*
4618 ** Open a file.
4619 */
4620 static int winOpen(
4621   sqlite3_vfs *pVfs,        /* Used to get maximum path name length */
4622   const char *zName,        /* Name of the file (UTF-8) */
4623   sqlite3_file *id,         /* Write the SQLite file handle here */
4624   int flags,                /* Open mode flags */
4625   int *pOutFlags            /* Status return flags */
4626 ){
4627   HANDLE h;
4628   DWORD lastErrno = 0;
4629   DWORD dwDesiredAccess;
4630   DWORD dwShareMode;
4631   DWORD dwCreationDisposition;
4632   DWORD dwFlagsAndAttributes = 0;
4633 #if SQLITE_OS_WINCE
4634   int isTemp = 0;
4635 #endif
4636   winFile *pFile = (winFile*)id;
4637   void *zConverted;              /* Filename in OS encoding */
4638   const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
4639   int cnt = 0;
4640 
4641   /* If argument zPath is a NULL pointer, this function is required to open
4642   ** a temporary file. Use this buffer to store the file name in.
4643   */
4644   char *zTmpname = 0; /* For temporary filename, if necessary. */
4645 
4646   int rc = SQLITE_OK;            /* Function Return Code */
4647 #if !defined(NDEBUG) || SQLITE_OS_WINCE
4648   int eType = flags&0xFFFFFF00;  /* Type of file to open */
4649 #endif
4650 
4651   int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
4652   int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
4653   int isCreate     = (flags & SQLITE_OPEN_CREATE);
4654   int isReadonly   = (flags & SQLITE_OPEN_READONLY);
4655   int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
4656 
4657 #ifndef NDEBUG
4658   int isOpenJournal = (isCreate && (
4659         eType==SQLITE_OPEN_MASTER_JOURNAL
4660      || eType==SQLITE_OPEN_MAIN_JOURNAL
4661      || eType==SQLITE_OPEN_WAL
4662   ));
4663 #endif
4664 
4665   OSTRACE(("OPEN name=%s, pFile=%p, flags=%x, pOutFlags=%p\n",
4666            zUtf8Name, id, flags, pOutFlags));
4667 
4668   /* Check the following statements are true:
4669   **
4670   **   (a) Exactly one of the READWRITE and READONLY flags must be set, and
4671   **   (b) if CREATE is set, then READWRITE must also be set, and
4672   **   (c) if EXCLUSIVE is set, then CREATE must also be set.
4673   **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
4674   */
4675   assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
4676   assert(isCreate==0 || isReadWrite);
4677   assert(isExclusive==0 || isCreate);
4678   assert(isDelete==0 || isCreate);
4679 
4680   /* The main DB, main journal, WAL file and master journal are never
4681   ** automatically deleted. Nor are they ever temporary files.  */
4682   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
4683   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
4684   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
4685   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
4686 
4687   /* Assert that the upper layer has set one of the "file-type" flags. */
4688   assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB
4689        || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL
4690        || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL
4691        || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
4692   );
4693 
4694   assert( pFile!=0 );
4695   memset(pFile, 0, sizeof(winFile));
4696   pFile->h = INVALID_HANDLE_VALUE;
4697 
4698 #if SQLITE_OS_WINRT
4699   if( !zUtf8Name && !sqlite3_temp_directory ){
4700     sqlite3_log(SQLITE_ERROR,
4701         "sqlite3_temp_directory variable should be set for WinRT");
4702   }
4703 #endif
4704 
4705   /* If the second argument to this function is NULL, generate a
4706   ** temporary file name to use
4707   */
4708   if( !zUtf8Name ){
4709     assert( isDelete && !isOpenJournal );
4710     rc = winGetTempname(pVfs, &zTmpname);
4711     if( rc!=SQLITE_OK ){
4712       OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
4713       return rc;
4714     }
4715     zUtf8Name = zTmpname;
4716   }
4717 
4718   /* Database filenames are double-zero terminated if they are not
4719   ** URIs with parameters.  Hence, they can always be passed into
4720   ** sqlite3_uri_parameter().
4721   */
4722   assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
4723        zUtf8Name[sqlite3Strlen30(zUtf8Name)+1]==0 );
4724 
4725   /* Convert the filename to the system encoding. */
4726   zConverted = winConvertFromUtf8Filename(zUtf8Name);
4727   if( zConverted==0 ){
4728     sqlite3_free(zTmpname);
4729     OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
4730     return SQLITE_IOERR_NOMEM_BKPT;
4731   }
4732 
4733   if( winIsDir(zConverted) ){
4734     sqlite3_free(zConverted);
4735     sqlite3_free(zTmpname);
4736     OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
4737     return SQLITE_CANTOPEN_ISDIR;
4738   }
4739 
4740   if( isReadWrite ){
4741     dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
4742   }else{
4743     dwDesiredAccess = GENERIC_READ;
4744   }
4745 
4746   /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is
4747   ** created. SQLite doesn't use it to indicate "exclusive access"
4748   ** as it is usually understood.
4749   */
4750   if( isExclusive ){
4751     /* Creates a new file, only if it does not already exist. */
4752     /* If the file exists, it fails. */
4753     dwCreationDisposition = CREATE_NEW;
4754   }else if( isCreate ){
4755     /* Open existing file, or create if it doesn't exist */
4756     dwCreationDisposition = OPEN_ALWAYS;
4757   }else{
4758     /* Opens a file, only if it exists. */
4759     dwCreationDisposition = OPEN_EXISTING;
4760   }
4761 
4762   dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
4763 
4764   if( isDelete ){
4765 #if SQLITE_OS_WINCE
4766     dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
4767     isTemp = 1;
4768 #else
4769     dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
4770                                | FILE_ATTRIBUTE_HIDDEN
4771                                | FILE_FLAG_DELETE_ON_CLOSE;
4772 #endif
4773   }else{
4774     dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
4775   }
4776   /* Reports from the internet are that performance is always
4777   ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
4778 #if SQLITE_OS_WINCE
4779   dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
4780 #endif
4781 
4782   if( osIsNT() ){
4783 #if SQLITE_OS_WINRT
4784     CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
4785     extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
4786     extendedParameters.dwFileAttributes =
4787             dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
4788     extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
4789     extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
4790     extendedParameters.lpSecurityAttributes = NULL;
4791     extendedParameters.hTemplateFile = NULL;
4792     while( (h = osCreateFile2((LPCWSTR)zConverted,
4793                               dwDesiredAccess,
4794                               dwShareMode,
4795                               dwCreationDisposition,
4796                               &extendedParameters))==INVALID_HANDLE_VALUE &&
4797                               winRetryIoerr(&cnt, &lastErrno) ){
4798                /* Noop */
4799     }
4800 #else
4801     while( (h = osCreateFileW((LPCWSTR)zConverted,
4802                               dwDesiredAccess,
4803                               dwShareMode, NULL,
4804                               dwCreationDisposition,
4805                               dwFlagsAndAttributes,
4806                               NULL))==INVALID_HANDLE_VALUE &&
4807                               winRetryIoerr(&cnt, &lastErrno) ){
4808                /* Noop */
4809     }
4810 #endif
4811   }
4812 #ifdef SQLITE_WIN32_HAS_ANSI
4813   else{
4814     while( (h = osCreateFileA((LPCSTR)zConverted,
4815                               dwDesiredAccess,
4816                               dwShareMode, NULL,
4817                               dwCreationDisposition,
4818                               dwFlagsAndAttributes,
4819                               NULL))==INVALID_HANDLE_VALUE &&
4820                               winRetryIoerr(&cnt, &lastErrno) ){
4821                /* Noop */
4822     }
4823   }
4824 #endif
4825   winLogIoerr(cnt, __LINE__);
4826 
4827   OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
4828            dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
4829 
4830   if( h==INVALID_HANDLE_VALUE ){
4831     pFile->lastErrno = lastErrno;
4832     winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
4833     sqlite3_free(zConverted);
4834     sqlite3_free(zTmpname);
4835     if( isReadWrite && !isExclusive ){
4836       return winOpen(pVfs, zName, id,
4837          ((flags|SQLITE_OPEN_READONLY) &
4838                      ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
4839          pOutFlags);
4840     }else{
4841       return SQLITE_CANTOPEN_BKPT;
4842     }
4843   }
4844 
4845   if( pOutFlags ){
4846     if( isReadWrite ){
4847       *pOutFlags = SQLITE_OPEN_READWRITE;
4848     }else{
4849       *pOutFlags = SQLITE_OPEN_READONLY;
4850     }
4851   }
4852 
4853   OSTRACE(("OPEN file=%p, name=%s, access=%lx, pOutFlags=%p, *pOutFlags=%d, "
4854            "rc=%s\n", h, zUtf8Name, dwDesiredAccess, pOutFlags, pOutFlags ?
4855            *pOutFlags : 0, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
4856 
4857 #if SQLITE_OS_WINCE
4858   if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
4859        && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
4860   ){
4861     osCloseHandle(h);
4862     sqlite3_free(zConverted);
4863     sqlite3_free(zTmpname);
4864     OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
4865     return rc;
4866   }
4867   if( isTemp ){
4868     pFile->zDeleteOnClose = zConverted;
4869   }else
4870 #endif
4871   {
4872     sqlite3_free(zConverted);
4873   }
4874 
4875   sqlite3_free(zTmpname);
4876   pFile->pMethod = &winIoMethod;
4877   pFile->pVfs = pVfs;
4878   pFile->h = h;
4879   if( isReadonly ){
4880     pFile->ctrlFlags |= WINFILE_RDONLY;
4881   }
4882   if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
4883     pFile->ctrlFlags |= WINFILE_PSOW;
4884   }
4885   pFile->lastErrno = NO_ERROR;
4886   pFile->zPath = zName;
4887 #if SQLITE_MAX_MMAP_SIZE>0
4888   pFile->hMap = NULL;
4889   pFile->pMapRegion = 0;
4890   pFile->mmapSize = 0;
4891   pFile->mmapSizeActual = 0;
4892   pFile->mmapSizeMax = sqlite3GlobalConfig.szMmap;
4893 #endif
4894 
4895   OpenCounter(+1);
4896   return rc;
4897 }
4898 
4899 /*
4900 ** Delete the named file.
4901 **
4902 ** Note that Windows does not allow a file to be deleted if some other
4903 ** process has it open.  Sometimes a virus scanner or indexing program
4904 ** will open a journal file shortly after it is created in order to do
4905 ** whatever it does.  While this other process is holding the
4906 ** file open, we will be unable to delete it.  To work around this
4907 ** problem, we delay 100 milliseconds and try to delete again.  Up
4908 ** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
4909 ** up and returning an error.
4910 */
4911 static int winDelete(
4912   sqlite3_vfs *pVfs,          /* Not used on win32 */
4913   const char *zFilename,      /* Name of file to delete */
4914   int syncDir                 /* Not used on win32 */
4915 ){
4916   int cnt = 0;
4917   int rc;
4918   DWORD attr;
4919   DWORD lastErrno = 0;
4920   void *zConverted;
4921   UNUSED_PARAMETER(pVfs);
4922   UNUSED_PARAMETER(syncDir);
4923 
4924   SimulateIOError(return SQLITE_IOERR_DELETE);
4925   OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));
4926 
4927   zConverted = winConvertFromUtf8Filename(zFilename);
4928   if( zConverted==0 ){
4929     OSTRACE(("DELETE name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
4930     return SQLITE_IOERR_NOMEM_BKPT;
4931   }
4932   if( osIsNT() ){
4933     do {
4934 #if SQLITE_OS_WINRT
4935       WIN32_FILE_ATTRIBUTE_DATA sAttrData;
4936       memset(&sAttrData, 0, sizeof(sAttrData));
4937       if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
4938                                   &sAttrData) ){
4939         attr = sAttrData.dwFileAttributes;
4940       }else{
4941         lastErrno = osGetLastError();
4942         if( lastErrno==ERROR_FILE_NOT_FOUND
4943          || lastErrno==ERROR_PATH_NOT_FOUND ){
4944           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
4945         }else{
4946           rc = SQLITE_ERROR;
4947         }
4948         break;
4949       }
4950 #else
4951       attr = osGetFileAttributesW(zConverted);
4952 #endif
4953       if ( attr==INVALID_FILE_ATTRIBUTES ){
4954         lastErrno = osGetLastError();
4955         if( lastErrno==ERROR_FILE_NOT_FOUND
4956          || lastErrno==ERROR_PATH_NOT_FOUND ){
4957           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
4958         }else{
4959           rc = SQLITE_ERROR;
4960         }
4961         break;
4962       }
4963       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
4964         rc = SQLITE_ERROR; /* Files only. */
4965         break;
4966       }
4967       if ( osDeleteFileW(zConverted) ){
4968         rc = SQLITE_OK; /* Deleted OK. */
4969         break;
4970       }
4971       if ( !winRetryIoerr(&cnt, &lastErrno) ){
4972         rc = SQLITE_ERROR; /* No more retries. */
4973         break;
4974       }
4975     } while(1);
4976   }
4977 #ifdef SQLITE_WIN32_HAS_ANSI
4978   else{
4979     do {
4980       attr = osGetFileAttributesA(zConverted);
4981       if ( attr==INVALID_FILE_ATTRIBUTES ){
4982         lastErrno = osGetLastError();
4983         if( lastErrno==ERROR_FILE_NOT_FOUND
4984          || lastErrno==ERROR_PATH_NOT_FOUND ){
4985           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
4986         }else{
4987           rc = SQLITE_ERROR;
4988         }
4989         break;
4990       }
4991       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
4992         rc = SQLITE_ERROR; /* Files only. */
4993         break;
4994       }
4995       if ( osDeleteFileA(zConverted) ){
4996         rc = SQLITE_OK; /* Deleted OK. */
4997         break;
4998       }
4999       if ( !winRetryIoerr(&cnt, &lastErrno) ){
5000         rc = SQLITE_ERROR; /* No more retries. */
5001         break;
5002       }
5003     } while(1);
5004   }
5005 #endif
5006   if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
5007     rc = winLogError(SQLITE_IOERR_DELETE, lastErrno, "winDelete", zFilename);
5008   }else{
5009     winLogIoerr(cnt, __LINE__);
5010   }
5011   sqlite3_free(zConverted);
5012   OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
5013   return rc;
5014 }
5015 
5016 /*
5017 ** Check the existence and status of a file.
5018 */
5019 static int winAccess(
5020   sqlite3_vfs *pVfs,         /* Not used on win32 */
5021   const char *zFilename,     /* Name of file to check */
5022   int flags,                 /* Type of test to make on this file */
5023   int *pResOut               /* OUT: Result */
5024 ){
5025   DWORD attr;
5026   int rc = 0;
5027   DWORD lastErrno = 0;
5028   void *zConverted;
5029   UNUSED_PARAMETER(pVfs);
5030 
5031   SimulateIOError( return SQLITE_IOERR_ACCESS; );
5032   OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
5033            zFilename, flags, pResOut));
5034 
5035   zConverted = winConvertFromUtf8Filename(zFilename);
5036   if( zConverted==0 ){
5037     OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
5038     return SQLITE_IOERR_NOMEM_BKPT;
5039   }
5040   if( osIsNT() ){
5041     int cnt = 0;
5042     WIN32_FILE_ATTRIBUTE_DATA sAttrData;
5043     memset(&sAttrData, 0, sizeof(sAttrData));
5044     while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
5045                              GetFileExInfoStandard,
5046                              &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
5047     if( rc ){
5048       /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
5049       ** as if it does not exist.
5050       */
5051       if(    flags==SQLITE_ACCESS_EXISTS
5052           && sAttrData.nFileSizeHigh==0
5053           && sAttrData.nFileSizeLow==0 ){
5054         attr = INVALID_FILE_ATTRIBUTES;
5055       }else{
5056         attr = sAttrData.dwFileAttributes;
5057       }
5058     }else{
5059       winLogIoerr(cnt, __LINE__);
5060       if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
5061         sqlite3_free(zConverted);
5062         return winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess",
5063                            zFilename);
5064       }else{
5065         attr = INVALID_FILE_ATTRIBUTES;
5066       }
5067     }
5068   }
5069 #ifdef SQLITE_WIN32_HAS_ANSI
5070   else{
5071     attr = osGetFileAttributesA((char*)zConverted);
5072   }
5073 #endif
5074   sqlite3_free(zConverted);
5075   switch( flags ){
5076     case SQLITE_ACCESS_READ:
5077     case SQLITE_ACCESS_EXISTS:
5078       rc = attr!=INVALID_FILE_ATTRIBUTES;
5079       break;
5080     case SQLITE_ACCESS_READWRITE:
5081       rc = attr!=INVALID_FILE_ATTRIBUTES &&
5082              (attr & FILE_ATTRIBUTE_READONLY)==0;
5083       break;
5084     default:
5085       assert(!"Invalid flags argument");
5086   }
5087   *pResOut = rc;
5088   OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
5089            zFilename, pResOut, *pResOut));
5090   return SQLITE_OK;
5091 }
5092 
5093 /*
5094 ** Returns non-zero if the specified path name starts with a drive letter
5095 ** followed by a colon character.
5096 */
5097 static BOOL winIsDriveLetterAndColon(
5098   const char *zPathname
5099 ){
5100   return ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' );
5101 }
5102 
5103 /*
5104 ** Returns non-zero if the specified path name should be used verbatim.  If
5105 ** non-zero is returned from this function, the calling function must simply
5106 ** use the provided path name verbatim -OR- resolve it into a full path name
5107 ** using the GetFullPathName Win32 API function (if available).
5108 */
5109 static BOOL winIsVerbatimPathname(
5110   const char *zPathname
5111 ){
5112   /*
5113   ** If the path name starts with a forward slash or a backslash, it is either
5114   ** a legal UNC name, a volume relative path, or an absolute path name in the
5115   ** "Unix" format on Windows.  There is no easy way to differentiate between
5116   ** the final two cases; therefore, we return the safer return value of TRUE
5117   ** so that callers of this function will simply use it verbatim.
5118   */
5119   if ( winIsDirSep(zPathname[0]) ){
5120     return TRUE;
5121   }
5122 
5123   /*
5124   ** If the path name starts with a letter and a colon it is either a volume
5125   ** relative path or an absolute path.  Callers of this function must not
5126   ** attempt to treat it as a relative path name (i.e. they should simply use
5127   ** it verbatim).
5128   */
5129   if ( winIsDriveLetterAndColon(zPathname) ){
5130     return TRUE;
5131   }
5132 
5133   /*
5134   ** If we get to this point, the path name should almost certainly be a purely
5135   ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
5136   */
5137   return FALSE;
5138 }
5139 
5140 /*
5141 ** Turn a relative pathname into a full pathname.  Write the full
5142 ** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
5143 ** bytes in size.
5144 */
5145 static int winFullPathname(
5146   sqlite3_vfs *pVfs,            /* Pointer to vfs object */
5147   const char *zRelative,        /* Possibly relative input path */
5148   int nFull,                    /* Size of output buffer in bytes */
5149   char *zFull                   /* Output buffer */
5150 ){
5151 
5152 #if defined(__CYGWIN__)
5153   SimulateIOError( return SQLITE_ERROR );
5154   UNUSED_PARAMETER(nFull);
5155   assert( nFull>=pVfs->mxPathname );
5156   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5157     /*
5158     ** NOTE: We are dealing with a relative path name and the data
5159     **       directory has been set.  Therefore, use it as the basis
5160     **       for converting the relative path name to an absolute
5161     **       one by prepending the data directory and a slash.
5162     */
5163     char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
5164     if( !zOut ){
5165       return SQLITE_IOERR_NOMEM_BKPT;
5166     }
5167     if( cygwin_conv_path(
5168             (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A) |
5169             CCP_RELATIVE, zRelative, zOut, pVfs->mxPathname+1)<0 ){
5170       sqlite3_free(zOut);
5171       return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
5172                          "winFullPathname1", zRelative);
5173     }else{
5174       char *zUtf8 = winConvertToUtf8Filename(zOut);
5175       if( !zUtf8 ){
5176         sqlite3_free(zOut);
5177         return SQLITE_IOERR_NOMEM_BKPT;
5178       }
5179       sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5180                        sqlite3_data_directory, winGetDirSep(), zUtf8);
5181       sqlite3_free(zUtf8);
5182       sqlite3_free(zOut);
5183     }
5184   }else{
5185     char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
5186     if( !zOut ){
5187       return SQLITE_IOERR_NOMEM_BKPT;
5188     }
5189     if( cygwin_conv_path(
5190             (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A),
5191             zRelative, zOut, pVfs->mxPathname+1)<0 ){
5192       sqlite3_free(zOut);
5193       return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
5194                          "winFullPathname2", zRelative);
5195     }else{
5196       char *zUtf8 = winConvertToUtf8Filename(zOut);
5197       if( !zUtf8 ){
5198         sqlite3_free(zOut);
5199         return SQLITE_IOERR_NOMEM_BKPT;
5200       }
5201       sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zUtf8);
5202       sqlite3_free(zUtf8);
5203       sqlite3_free(zOut);
5204     }
5205   }
5206   return SQLITE_OK;
5207 #endif
5208 
5209 #if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
5210   SimulateIOError( return SQLITE_ERROR );
5211   /* WinCE has no concept of a relative pathname, or so I am told. */
5212   /* WinRT has no way to convert a relative path to an absolute one. */
5213   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5214     /*
5215     ** NOTE: We are dealing with a relative path name and the data
5216     **       directory has been set.  Therefore, use it as the basis
5217     **       for converting the relative path name to an absolute
5218     **       one by prepending the data directory and a backslash.
5219     */
5220     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5221                      sqlite3_data_directory, winGetDirSep(), zRelative);
5222   }else{
5223     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
5224   }
5225   return SQLITE_OK;
5226 #endif
5227 
5228 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
5229   DWORD nByte;
5230   void *zConverted;
5231   char *zOut;
5232 
5233   /* If this path name begins with "/X:", where "X" is any alphabetic
5234   ** character, discard the initial "/" from the pathname.
5235   */
5236   if( zRelative[0]=='/' && winIsDriveLetterAndColon(zRelative+1) ){
5237     zRelative++;
5238   }
5239 
5240   /* It's odd to simulate an io-error here, but really this is just
5241   ** using the io-error infrastructure to test that SQLite handles this
5242   ** function failing. This function could fail if, for example, the
5243   ** current working directory has been unlinked.
5244   */
5245   SimulateIOError( return SQLITE_ERROR );
5246   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5247     /*
5248     ** NOTE: We are dealing with a relative path name and the data
5249     **       directory has been set.  Therefore, use it as the basis
5250     **       for converting the relative path name to an absolute
5251     **       one by prepending the data directory and a backslash.
5252     */
5253     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5254                      sqlite3_data_directory, winGetDirSep(), zRelative);
5255     return SQLITE_OK;
5256   }
5257   zConverted = winConvertFromUtf8Filename(zRelative);
5258   if( zConverted==0 ){
5259     return SQLITE_IOERR_NOMEM_BKPT;
5260   }
5261   if( osIsNT() ){
5262     LPWSTR zTemp;
5263     nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
5264     if( nByte==0 ){
5265       sqlite3_free(zConverted);
5266       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5267                          "winFullPathname1", zRelative);
5268     }
5269     nByte += 3;
5270     zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
5271     if( zTemp==0 ){
5272       sqlite3_free(zConverted);
5273       return SQLITE_IOERR_NOMEM_BKPT;
5274     }
5275     nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
5276     if( nByte==0 ){
5277       sqlite3_free(zConverted);
5278       sqlite3_free(zTemp);
5279       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5280                          "winFullPathname2", zRelative);
5281     }
5282     sqlite3_free(zConverted);
5283     zOut = winUnicodeToUtf8(zTemp);
5284     sqlite3_free(zTemp);
5285   }
5286 #ifdef SQLITE_WIN32_HAS_ANSI
5287   else{
5288     char *zTemp;
5289     nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
5290     if( nByte==0 ){
5291       sqlite3_free(zConverted);
5292       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5293                          "winFullPathname3", zRelative);
5294     }
5295     nByte += 3;
5296     zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
5297     if( zTemp==0 ){
5298       sqlite3_free(zConverted);
5299       return SQLITE_IOERR_NOMEM_BKPT;
5300     }
5301     nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
5302     if( nByte==0 ){
5303       sqlite3_free(zConverted);
5304       sqlite3_free(zTemp);
5305       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5306                          "winFullPathname4", zRelative);
5307     }
5308     sqlite3_free(zConverted);
5309     zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
5310     sqlite3_free(zTemp);
5311   }
5312 #endif
5313   if( zOut ){
5314     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zOut);
5315     sqlite3_free(zOut);
5316     return SQLITE_OK;
5317   }else{
5318     return SQLITE_IOERR_NOMEM_BKPT;
5319   }
5320 #endif
5321 }
5322 
5323 #ifndef SQLITE_OMIT_LOAD_EXTENSION
5324 /*
5325 ** Interfaces for opening a shared library, finding entry points
5326 ** within the shared library, and closing the shared library.
5327 */
5328 static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
5329   HANDLE h;
5330 #if defined(__CYGWIN__)
5331   int nFull = pVfs->mxPathname+1;
5332   char *zFull = sqlite3MallocZero( nFull );
5333   void *zConverted = 0;
5334   if( zFull==0 ){
5335     OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
5336     return 0;
5337   }
5338   if( winFullPathname(pVfs, zFilename, nFull, zFull)!=SQLITE_OK ){
5339     sqlite3_free(zFull);
5340     OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
5341     return 0;
5342   }
5343   zConverted = winConvertFromUtf8Filename(zFull);
5344   sqlite3_free(zFull);
5345 #else
5346   void *zConverted = winConvertFromUtf8Filename(zFilename);
5347   UNUSED_PARAMETER(pVfs);
5348 #endif
5349   if( zConverted==0 ){
5350     OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
5351     return 0;
5352   }
5353   if( osIsNT() ){
5354 #if SQLITE_OS_WINRT
5355     h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
5356 #else
5357     h = osLoadLibraryW((LPCWSTR)zConverted);
5358 #endif
5359   }
5360 #ifdef SQLITE_WIN32_HAS_ANSI
5361   else{
5362     h = osLoadLibraryA((char*)zConverted);
5363   }
5364 #endif
5365   OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)h));
5366   sqlite3_free(zConverted);
5367   return (void*)h;
5368 }
5369 static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
5370   UNUSED_PARAMETER(pVfs);
5371   winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
5372 }
5373 static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
5374   FARPROC proc;
5375   UNUSED_PARAMETER(pVfs);
5376   proc = osGetProcAddressA((HANDLE)pH, zSym);
5377   OSTRACE(("DLSYM handle=%p, symbol=%s, address=%p\n",
5378            (void*)pH, zSym, (void*)proc));
5379   return (void(*)(void))proc;
5380 }
5381 static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
5382   UNUSED_PARAMETER(pVfs);
5383   osFreeLibrary((HANDLE)pHandle);
5384   OSTRACE(("DLCLOSE handle=%p\n", (void*)pHandle));
5385 }
5386 #else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
5387   #define winDlOpen  0
5388   #define winDlError 0
5389   #define winDlSym   0
5390   #define winDlClose 0
5391 #endif
5392 
5393 /* State information for the randomness gatherer. */
5394 typedef struct EntropyGatherer EntropyGatherer;
5395 struct EntropyGatherer {
5396   unsigned char *a;   /* Gather entropy into this buffer */
5397   int na;             /* Size of a[] in bytes */
5398   int i;              /* XOR next input into a[i] */
5399   int nXor;           /* Number of XOR operations done */
5400 };
5401 
5402 #if !defined(SQLITE_TEST) && !defined(SQLITE_OMIT_RANDOMNESS)
5403 /* Mix sz bytes of entropy into p. */
5404 static void xorMemory(EntropyGatherer *p, unsigned char *x, int sz){
5405   int j, k;
5406   for(j=0, k=p->i; j<sz; j++){
5407     p->a[k++] ^= x[j];
5408     if( k>=p->na ) k = 0;
5409   }
5410   p->i = k;
5411   p->nXor += sz;
5412 }
5413 #endif /* !defined(SQLITE_TEST) && !defined(SQLITE_OMIT_RANDOMNESS) */
5414 
5415 /*
5416 ** Write up to nBuf bytes of randomness into zBuf.
5417 */
5418 static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5419 #if defined(SQLITE_TEST) || defined(SQLITE_OMIT_RANDOMNESS)
5420   UNUSED_PARAMETER(pVfs);
5421   memset(zBuf, 0, nBuf);
5422   return nBuf;
5423 #else
5424   EntropyGatherer e;
5425   UNUSED_PARAMETER(pVfs);
5426   memset(zBuf, 0, nBuf);
5427 #if defined(_MSC_VER) && _MSC_VER>=1400
5428   rand_s((int*)zBuf); /* rand_s() is not available with MinGW */
5429 #endif /* defined(_MSC_VER) && _MSC_VER>=1400 */
5430   e.a = (unsigned char*)zBuf;
5431   e.na = nBuf;
5432   e.nXor = 0;
5433   e.i = 0;
5434   {
5435     SYSTEMTIME x;
5436     osGetSystemTime(&x);
5437     xorMemory(&e, (unsigned char*)&x, sizeof(SYSTEMTIME));
5438   }
5439   {
5440     DWORD pid = osGetCurrentProcessId();
5441     xorMemory(&e, (unsigned char*)&pid, sizeof(DWORD));
5442   }
5443 #if SQLITE_OS_WINRT
5444   {
5445     ULONGLONG cnt = osGetTickCount64();
5446     xorMemory(&e, (unsigned char*)&cnt, sizeof(ULONGLONG));
5447   }
5448 #else
5449   {
5450     DWORD cnt = osGetTickCount();
5451     xorMemory(&e, (unsigned char*)&cnt, sizeof(DWORD));
5452   }
5453 #endif /* SQLITE_OS_WINRT */
5454   {
5455     LARGE_INTEGER i;
5456     osQueryPerformanceCounter(&i);
5457     xorMemory(&e, (unsigned char*)&i, sizeof(LARGE_INTEGER));
5458   }
5459 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID
5460   {
5461     UUID id;
5462     memset(&id, 0, sizeof(UUID));
5463     osUuidCreate(&id);
5464     xorMemory(&e, (unsigned char*)&id, sizeof(UUID));
5465     memset(&id, 0, sizeof(UUID));
5466     osUuidCreateSequential(&id);
5467     xorMemory(&e, (unsigned char*)&id, sizeof(UUID));
5468   }
5469 #endif /* !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_WIN32_USE_UUID */
5470   return e.nXor>nBuf ? nBuf : e.nXor;
5471 #endif /* defined(SQLITE_TEST) || defined(SQLITE_OMIT_RANDOMNESS) */
5472 }
5473 
5474 
5475 /*
5476 ** Sleep for a little while.  Return the amount of time slept.
5477 */
5478 static int winSleep(sqlite3_vfs *pVfs, int microsec){
5479   sqlite3_win32_sleep((microsec+999)/1000);
5480   UNUSED_PARAMETER(pVfs);
5481   return ((microsec+999)/1000)*1000;
5482 }
5483 
5484 /*
5485 ** The following variable, if set to a non-zero value, is interpreted as
5486 ** the number of seconds since 1970 and is used to set the result of
5487 ** sqlite3OsCurrentTime() during testing.
5488 */
5489 #ifdef SQLITE_TEST
5490 int sqlite3_current_time = 0;  /* Fake system time in seconds since 1970. */
5491 #endif
5492 
5493 /*
5494 ** Find the current time (in Universal Coordinated Time).  Write into *piNow
5495 ** the current time and date as a Julian Day number times 86_400_000.  In
5496 ** other words, write into *piNow the number of milliseconds since the Julian
5497 ** epoch of noon in Greenwich on November 24, 4714 B.C according to the
5498 ** proleptic Gregorian calendar.
5499 **
5500 ** On success, return SQLITE_OK.  Return SQLITE_ERROR if the time and date
5501 ** cannot be found.
5502 */
5503 static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
5504   /* FILETIME structure is a 64-bit value representing the number of
5505      100-nanosecond intervals since January 1, 1601 (= JD 2305813.5).
5506   */
5507   FILETIME ft;
5508   static const sqlite3_int64 winFiletimeEpoch = 23058135*(sqlite3_int64)8640000;
5509 #ifdef SQLITE_TEST
5510   static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
5511 #endif
5512   /* 2^32 - to avoid use of LL and warnings in gcc */
5513   static const sqlite3_int64 max32BitValue =
5514       (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 +
5515       (sqlite3_int64)294967296;
5516 
5517 #if SQLITE_OS_WINCE
5518   SYSTEMTIME time;
5519   osGetSystemTime(&time);
5520   /* if SystemTimeToFileTime() fails, it returns zero. */
5521   if (!osSystemTimeToFileTime(&time,&ft)){
5522     return SQLITE_ERROR;
5523   }
5524 #else
5525   osGetSystemTimeAsFileTime( &ft );
5526 #endif
5527 
5528   *piNow = winFiletimeEpoch +
5529             ((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) +
5530                (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000;
5531 
5532 #ifdef SQLITE_TEST
5533   if( sqlite3_current_time ){
5534     *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
5535   }
5536 #endif
5537   UNUSED_PARAMETER(pVfs);
5538   return SQLITE_OK;
5539 }
5540 
5541 /*
5542 ** Find the current time (in Universal Coordinated Time).  Write the
5543 ** current time and date as a Julian Day number into *prNow and
5544 ** return 0.  Return 1 if the time and date cannot be found.
5545 */
5546 static int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
5547   int rc;
5548   sqlite3_int64 i;
5549   rc = winCurrentTimeInt64(pVfs, &i);
5550   if( !rc ){
5551     *prNow = i/86400000.0;
5552   }
5553   return rc;
5554 }
5555 
5556 /*
5557 ** The idea is that this function works like a combination of
5558 ** GetLastError() and FormatMessage() on Windows (or errno and
5559 ** strerror_r() on Unix). After an error is returned by an OS
5560 ** function, SQLite calls this function with zBuf pointing to
5561 ** a buffer of nBuf bytes. The OS layer should populate the
5562 ** buffer with a nul-terminated UTF-8 encoded error message
5563 ** describing the last IO error to have occurred within the calling
5564 ** thread.
5565 **
5566 ** If the error message is too large for the supplied buffer,
5567 ** it should be truncated. The return value of xGetLastError
5568 ** is zero if the error message fits in the buffer, or non-zero
5569 ** otherwise (if the message was truncated). If non-zero is returned,
5570 ** then it is not necessary to include the nul-terminator character
5571 ** in the output buffer.
5572 **
5573 ** Not supplying an error message will have no adverse effect
5574 ** on SQLite. It is fine to have an implementation that never
5575 ** returns an error message:
5576 **
5577 **   int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5578 **     assert(zBuf[0]=='\0');
5579 **     return 0;
5580 **   }
5581 **
5582 ** However if an error message is supplied, it will be incorporated
5583 ** by sqlite into the error message available to the user using
5584 ** sqlite3_errmsg(), possibly making IO errors easier to debug.
5585 */
5586 static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5587   UNUSED_PARAMETER(pVfs);
5588   return winGetLastErrorMsg(osGetLastError(), nBuf, zBuf);
5589 }
5590 
5591 /*
5592 ** Initialize and deinitialize the operating system interface.
5593 */
5594 int sqlite3_os_init(void){
5595   static sqlite3_vfs winVfs = {
5596     3,                   /* iVersion */
5597     sizeof(winFile),     /* szOsFile */
5598     SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
5599     0,                   /* pNext */
5600     "win32",             /* zName */
5601     0,                   /* pAppData */
5602     winOpen,             /* xOpen */
5603     winDelete,           /* xDelete */
5604     winAccess,           /* xAccess */
5605     winFullPathname,     /* xFullPathname */
5606     winDlOpen,           /* xDlOpen */
5607     winDlError,          /* xDlError */
5608     winDlSym,            /* xDlSym */
5609     winDlClose,          /* xDlClose */
5610     winRandomness,       /* xRandomness */
5611     winSleep,            /* xSleep */
5612     winCurrentTime,      /* xCurrentTime */
5613     winGetLastError,     /* xGetLastError */
5614     winCurrentTimeInt64, /* xCurrentTimeInt64 */
5615     winSetSystemCall,    /* xSetSystemCall */
5616     winGetSystemCall,    /* xGetSystemCall */
5617     winNextSystemCall,   /* xNextSystemCall */
5618   };
5619 #if defined(SQLITE_WIN32_HAS_WIDE)
5620   static sqlite3_vfs winLongPathVfs = {
5621     3,                   /* iVersion */
5622     sizeof(winFile),     /* szOsFile */
5623     SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
5624     0,                   /* pNext */
5625     "win32-longpath",    /* zName */
5626     0,                   /* pAppData */
5627     winOpen,             /* xOpen */
5628     winDelete,           /* xDelete */
5629     winAccess,           /* xAccess */
5630     winFullPathname,     /* xFullPathname */
5631     winDlOpen,           /* xDlOpen */
5632     winDlError,          /* xDlError */
5633     winDlSym,            /* xDlSym */
5634     winDlClose,          /* xDlClose */
5635     winRandomness,       /* xRandomness */
5636     winSleep,            /* xSleep */
5637     winCurrentTime,      /* xCurrentTime */
5638     winGetLastError,     /* xGetLastError */
5639     winCurrentTimeInt64, /* xCurrentTimeInt64 */
5640     winSetSystemCall,    /* xSetSystemCall */
5641     winGetSystemCall,    /* xGetSystemCall */
5642     winNextSystemCall,   /* xNextSystemCall */
5643   };
5644 #endif
5645 
5646   /* Double-check that the aSyscall[] array has been constructed
5647   ** correctly.  See ticket [bb3a86e890c8e96ab] */
5648   assert( ArraySize(aSyscall)==80 );
5649 
5650   /* get memory map allocation granularity */
5651   memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
5652 #if SQLITE_OS_WINRT
5653   osGetNativeSystemInfo(&winSysInfo);
5654 #else
5655   osGetSystemInfo(&winSysInfo);
5656 #endif
5657   assert( winSysInfo.dwAllocationGranularity>0 );
5658   assert( winSysInfo.dwPageSize>0 );
5659 
5660   sqlite3_vfs_register(&winVfs, 1);
5661 
5662 #if defined(SQLITE_WIN32_HAS_WIDE)
5663   sqlite3_vfs_register(&winLongPathVfs, 0);
5664 #endif
5665 
5666   return SQLITE_OK;
5667 }
5668 
5669 int sqlite3_os_end(void){
5670 #if SQLITE_OS_WINRT
5671   if( sleepObj!=NULL ){
5672     osCloseHandle(sleepObj);
5673     sleepObj = NULL;
5674   }
5675 #endif
5676   return SQLITE_OK;
5677 }
5678 
5679 #endif /* SQLITE_OS_WIN */
5680