xref: /sqlite-3.40.0/src/os_win.c (revision a3fdec71)
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 #ifdef __CYGWIN__
19 # include <sys/cygwin.h>
20 # include <errno.h> /* amalgamator: keep */
21 #endif
22 
23 /*
24 ** Include code that is common to all os_*.c files
25 */
26 #include "os_common.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 /*
38 ** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
39 ** based on the sub-platform)?
40 */
41 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(SQLITE_WIN32_NO_ANSI)
42 #  define SQLITE_WIN32_HAS_ANSI
43 #endif
44 
45 /*
46 ** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
47 ** based on the sub-platform)?
48 */
49 #if (SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT) && \
50     !defined(SQLITE_WIN32_NO_WIDE)
51 #  define SQLITE_WIN32_HAS_WIDE
52 #endif
53 
54 /*
55 ** Make sure at least one set of Win32 APIs is available.
56 */
57 #if !defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_WIN32_HAS_WIDE)
58 #  error "At least one of SQLITE_WIN32_HAS_ANSI and SQLITE_WIN32_HAS_WIDE\
59  must be defined."
60 #endif
61 
62 /*
63 ** Define the required Windows SDK version constants if they are not
64 ** already available.
65 */
66 #ifndef NTDDI_WIN8
67 #  define NTDDI_WIN8                        0x06020000
68 #endif
69 
70 #ifndef NTDDI_WINBLUE
71 #  define NTDDI_WINBLUE                     0x06030000
72 #endif
73 
74 /*
75 ** Check if the GetVersionEx[AW] functions should be considered deprecated
76 ** and avoid using them in that case.  It should be noted here that if the
77 ** value of the SQLITE_WIN32_GETVERSIONEX pre-processor macro is zero
78 ** (whether via this block or via being manually specified), that implies
79 ** the underlying operating system will always be based on the Windows NT
80 ** Kernel.
81 */
82 #ifndef SQLITE_WIN32_GETVERSIONEX
83 #  if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WINBLUE
84 #    define SQLITE_WIN32_GETVERSIONEX   0
85 #  else
86 #    define SQLITE_WIN32_GETVERSIONEX   1
87 #  endif
88 #endif
89 
90 /*
91 ** This constant should already be defined (in the "WinDef.h" SDK file).
92 */
93 #ifndef MAX_PATH
94 #  define MAX_PATH                      (260)
95 #endif
96 
97 /*
98 ** Maximum pathname length (in chars) for Win32.  This should normally be
99 ** MAX_PATH.
100 */
101 #ifndef SQLITE_WIN32_MAX_PATH_CHARS
102 #  define SQLITE_WIN32_MAX_PATH_CHARS   (MAX_PATH)
103 #endif
104 
105 /*
106 ** This constant should already be defined (in the "WinNT.h" SDK file).
107 */
108 #ifndef UNICODE_STRING_MAX_CHARS
109 #  define UNICODE_STRING_MAX_CHARS      (32767)
110 #endif
111 
112 /*
113 ** Maximum pathname length (in chars) for WinNT.  This should normally be
114 ** UNICODE_STRING_MAX_CHARS.
115 */
116 #ifndef SQLITE_WINNT_MAX_PATH_CHARS
117 #  define SQLITE_WINNT_MAX_PATH_CHARS   (UNICODE_STRING_MAX_CHARS)
118 #endif
119 
120 /*
121 ** Maximum pathname length (in bytes) for Win32.  The MAX_PATH macro is in
122 ** characters, so we allocate 4 bytes per character assuming worst-case of
123 ** 4-bytes-per-character for UTF8.
124 */
125 #ifndef SQLITE_WIN32_MAX_PATH_BYTES
126 #  define SQLITE_WIN32_MAX_PATH_BYTES   (SQLITE_WIN32_MAX_PATH_CHARS*4)
127 #endif
128 
129 /*
130 ** Maximum pathname length (in bytes) for WinNT.  This should normally be
131 ** UNICODE_STRING_MAX_CHARS * sizeof(WCHAR).
132 */
133 #ifndef SQLITE_WINNT_MAX_PATH_BYTES
134 #  define SQLITE_WINNT_MAX_PATH_BYTES   \
135                             (sizeof(WCHAR) * SQLITE_WINNT_MAX_PATH_CHARS)
136 #endif
137 
138 /*
139 ** Maximum error message length (in chars) for WinRT.
140 */
141 #ifndef SQLITE_WIN32_MAX_ERRMSG_CHARS
142 #  define SQLITE_WIN32_MAX_ERRMSG_CHARS (1024)
143 #endif
144 
145 /*
146 ** Returns non-zero if the character should be treated as a directory
147 ** separator.
148 */
149 #ifndef winIsDirSep
150 #  define winIsDirSep(a)                (((a) == '/') || ((a) == '\\'))
151 #endif
152 
153 /*
154 ** This macro is used when a local variable is set to a value that is
155 ** [sometimes] not used by the code (e.g. via conditional compilation).
156 */
157 #ifndef UNUSED_VARIABLE_VALUE
158 #  define UNUSED_VARIABLE_VALUE(x) (void)(x)
159 #endif
160 
161 /*
162 ** Returns the character that should be used as the directory separator.
163 */
164 #ifndef winGetDirSep
165 #  define winGetDirSep()                '\\'
166 #endif
167 
168 /*
169 ** Do we need to manually define the Win32 file mapping APIs for use with WAL
170 ** mode (e.g. these APIs are available in the Windows CE SDK; however, they
171 ** are not present in the header file)?
172 */
173 #if SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL)
174 /*
175 ** Two of the file mapping APIs are different under WinRT.  Figure out which
176 ** set we need.
177 */
178 #if SQLITE_OS_WINRT
179 WINBASEAPI HANDLE WINAPI CreateFileMappingFromApp(HANDLE, \
180         LPSECURITY_ATTRIBUTES, ULONG, ULONG64, LPCWSTR);
181 
182 WINBASEAPI LPVOID WINAPI MapViewOfFileFromApp(HANDLE, ULONG, ULONG64, SIZE_T);
183 #else
184 #if defined(SQLITE_WIN32_HAS_ANSI)
185 WINBASEAPI HANDLE WINAPI CreateFileMappingA(HANDLE, LPSECURITY_ATTRIBUTES, \
186         DWORD, DWORD, DWORD, LPCSTR);
187 #endif /* defined(SQLITE_WIN32_HAS_ANSI) */
188 
189 #if defined(SQLITE_WIN32_HAS_WIDE)
190 WINBASEAPI HANDLE WINAPI CreateFileMappingW(HANDLE, LPSECURITY_ATTRIBUTES, \
191         DWORD, DWORD, DWORD, LPCWSTR);
192 #endif /* defined(SQLITE_WIN32_HAS_WIDE) */
193 
194 WINBASEAPI LPVOID WINAPI MapViewOfFile(HANDLE, DWORD, DWORD, DWORD, SIZE_T);
195 #endif /* SQLITE_OS_WINRT */
196 
197 /*
198 ** This file mapping API is common to both Win32 and WinRT.
199 */
200 WINBASEAPI BOOL WINAPI UnmapViewOfFile(LPCVOID);
201 #endif /* SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL) */
202 
203 /*
204 ** Some Microsoft compilers lack this definition.
205 */
206 #ifndef INVALID_FILE_ATTRIBUTES
207 # define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
208 #endif
209 
210 #ifndef FILE_FLAG_MASK
211 # define FILE_FLAG_MASK          (0xFF3C0000)
212 #endif
213 
214 #ifndef FILE_ATTRIBUTE_MASK
215 # define FILE_ATTRIBUTE_MASK     (0x0003FFF7)
216 #endif
217 
218 #ifndef SQLITE_OMIT_WAL
219 /* Forward references to structures used for WAL */
220 typedef struct winShm winShm;           /* A connection to shared-memory */
221 typedef struct winShmNode winShmNode;   /* A region of shared-memory */
222 #endif
223 
224 /*
225 ** WinCE lacks native support for file locking so we have to fake it
226 ** with some code of our own.
227 */
228 #if SQLITE_OS_WINCE
229 typedef struct winceLock {
230   int nReaders;       /* Number of reader locks obtained */
231   BOOL bPending;      /* Indicates a pending lock has been obtained */
232   BOOL bReserved;     /* Indicates a reserved lock has been obtained */
233   BOOL bExclusive;    /* Indicates an exclusive lock has been obtained */
234 } winceLock;
235 #endif
236 
237 /*
238 ** The winFile structure is a subclass of sqlite3_file* specific to the win32
239 ** portability layer.
240 */
241 typedef struct winFile winFile;
242 struct winFile {
243   const sqlite3_io_methods *pMethod; /*** Must be first ***/
244   sqlite3_vfs *pVfs;      /* The VFS used to open this file */
245   HANDLE h;               /* Handle for accessing the file */
246   u8 locktype;            /* Type of lock currently held on this file */
247   short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
248   u8 ctrlFlags;           /* Flags.  See WINFILE_* below */
249   DWORD lastErrno;        /* The Windows errno from the last I/O error */
250 #ifndef SQLITE_OMIT_WAL
251   winShm *pShm;           /* Instance of shared memory on this file */
252 #endif
253   const char *zPath;      /* Full pathname of this file */
254   int szChunk;            /* Chunk size configured by FCNTL_CHUNK_SIZE */
255 #if SQLITE_OS_WINCE
256   LPWSTR zDeleteOnClose;  /* Name of file to delete when closing */
257   HANDLE hMutex;          /* Mutex used to control access to shared lock */
258   HANDLE hShared;         /* Shared memory segment used for locking */
259   winceLock local;        /* Locks obtained by this instance of winFile */
260   winceLock *shared;      /* Global shared lock memory for the file  */
261 #endif
262 #if SQLITE_MAX_MMAP_SIZE>0
263   int nFetchOut;                /* Number of outstanding xFetch references */
264   HANDLE hMap;                  /* Handle for accessing memory mapping */
265   void *pMapRegion;             /* Area memory mapped */
266   sqlite3_int64 mmapSize;       /* Usable size of mapped region */
267   sqlite3_int64 mmapSizeActual; /* Actual size of mapped region */
268   sqlite3_int64 mmapSizeMax;    /* Configured FCNTL_MMAP_SIZE value */
269 #endif
270 };
271 
272 /*
273 ** Allowed values for winFile.ctrlFlags
274 */
275 #define WINFILE_RDONLY          0x02   /* Connection is read only */
276 #define WINFILE_PERSIST_WAL     0x04   /* Persistent WAL mode */
277 #define WINFILE_PSOW            0x10   /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
278 
279 /*
280  * The size of the buffer used by sqlite3_win32_write_debug().
281  */
282 #ifndef SQLITE_WIN32_DBG_BUF_SIZE
283 #  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
284 #endif
285 
286 /*
287  * The value used with sqlite3_win32_set_directory() to specify that
288  * the data directory should be changed.
289  */
290 #ifndef SQLITE_WIN32_DATA_DIRECTORY_TYPE
291 #  define SQLITE_WIN32_DATA_DIRECTORY_TYPE (1)
292 #endif
293 
294 /*
295  * The value used with sqlite3_win32_set_directory() to specify that
296  * the temporary directory should be changed.
297  */
298 #ifndef SQLITE_WIN32_TEMP_DIRECTORY_TYPE
299 #  define SQLITE_WIN32_TEMP_DIRECTORY_TYPE (2)
300 #endif
301 
302 /*
303  * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
304  * various Win32 API heap functions instead of our own.
305  */
306 #ifdef SQLITE_WIN32_MALLOC
307 
308 /*
309  * If this is non-zero, an isolated heap will be created by the native Win32
310  * allocator subsystem; otherwise, the default process heap will be used.  This
311  * setting has no effect when compiling for WinRT.  By default, this is enabled
312  * and an isolated heap will be created to store all allocated data.
313  *
314  ******************************************************************************
315  * WARNING: It is important to note that when this setting is non-zero and the
316  *          winMemShutdown function is called (e.g. by the sqlite3_shutdown
317  *          function), all data that was allocated using the isolated heap will
318  *          be freed immediately and any attempt to access any of that freed
319  *          data will almost certainly result in an immediate access violation.
320  ******************************************************************************
321  */
322 #ifndef SQLITE_WIN32_HEAP_CREATE
323 #  define SQLITE_WIN32_HEAP_CREATE    (TRUE)
324 #endif
325 
326 /*
327  * The initial size of the Win32-specific heap.  This value may be zero.
328  */
329 #ifndef SQLITE_WIN32_HEAP_INIT_SIZE
330 #  define SQLITE_WIN32_HEAP_INIT_SIZE ((SQLITE_DEFAULT_CACHE_SIZE) * \
331                                        (SQLITE_DEFAULT_PAGE_SIZE) + 4194304)
332 #endif
333 
334 /*
335  * The maximum size of the Win32-specific heap.  This value may be zero.
336  */
337 #ifndef SQLITE_WIN32_HEAP_MAX_SIZE
338 #  define SQLITE_WIN32_HEAP_MAX_SIZE  (0)
339 #endif
340 
341 /*
342  * The extra flags to use in calls to the Win32 heap APIs.  This value may be
343  * zero for the default behavior.
344  */
345 #ifndef SQLITE_WIN32_HEAP_FLAGS
346 #  define SQLITE_WIN32_HEAP_FLAGS     (0)
347 #endif
348 
349 
350 /*
351 ** The winMemData structure stores information required by the Win32-specific
352 ** sqlite3_mem_methods implementation.
353 */
354 typedef struct winMemData winMemData;
355 struct winMemData {
356 #ifndef NDEBUG
357   u32 magic1;   /* Magic number to detect structure corruption. */
358 #endif
359   HANDLE hHeap; /* The handle to our heap. */
360   BOOL bOwned;  /* Do we own the heap (i.e. destroy it on shutdown)? */
361 #ifndef NDEBUG
362   u32 magic2;   /* Magic number to detect structure corruption. */
363 #endif
364 };
365 
366 #ifndef NDEBUG
367 #define WINMEM_MAGIC1     0x42b2830b
368 #define WINMEM_MAGIC2     0xbd4d7cf4
369 #endif
370 
371 static struct winMemData win_mem_data = {
372 #ifndef NDEBUG
373   WINMEM_MAGIC1,
374 #endif
375   NULL, FALSE
376 #ifndef NDEBUG
377   ,WINMEM_MAGIC2
378 #endif
379 };
380 
381 #ifndef NDEBUG
382 #define winMemAssertMagic1() assert( win_mem_data.magic1==WINMEM_MAGIC1 )
383 #define winMemAssertMagic2() assert( win_mem_data.magic2==WINMEM_MAGIC2 )
384 #define winMemAssertMagic()  winMemAssertMagic1(); winMemAssertMagic2();
385 #else
386 #define winMemAssertMagic()
387 #endif
388 
389 #define winMemGetDataPtr()  &win_mem_data
390 #define winMemGetHeap()     win_mem_data.hHeap
391 #define winMemGetOwned()    win_mem_data.bOwned
392 
393 static void *winMemMalloc(int nBytes);
394 static void winMemFree(void *pPrior);
395 static void *winMemRealloc(void *pPrior, int nBytes);
396 static int winMemSize(void *p);
397 static int winMemRoundup(int n);
398 static int winMemInit(void *pAppData);
399 static void winMemShutdown(void *pAppData);
400 
401 const sqlite3_mem_methods *sqlite3MemGetWin32(void);
402 #endif /* SQLITE_WIN32_MALLOC */
403 
404 /*
405 ** The following variable is (normally) set once and never changes
406 ** thereafter.  It records whether the operating system is Win9x
407 ** or WinNT.
408 **
409 ** 0:   Operating system unknown.
410 ** 1:   Operating system is Win9x.
411 ** 2:   Operating system is WinNT.
412 **
413 ** In order to facilitate testing on a WinNT system, the test fixture
414 ** can manually set this value to 1 to emulate Win98 behavior.
415 */
416 #ifdef SQLITE_TEST
417 int sqlite3_os_type = 0;
418 #elif !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
419       defined(SQLITE_WIN32_HAS_ANSI) && defined(SQLITE_WIN32_HAS_WIDE)
420 static int sqlite3_os_type = 0;
421 #endif
422 
423 #ifndef SYSCALL
424 #  define SYSCALL sqlite3_syscall_ptr
425 #endif
426 
427 /*
428 ** This function is not available on Windows CE or WinRT.
429  */
430 
431 #if SQLITE_OS_WINCE || SQLITE_OS_WINRT
432 #  define osAreFileApisANSI()       1
433 #endif
434 
435 /*
436 ** Many system calls are accessed through pointer-to-functions so that
437 ** they may be overridden at runtime to facilitate fault injection during
438 ** testing and sandboxing.  The following array holds the names and pointers
439 ** to all overrideable system calls.
440 */
441 static struct win_syscall {
442   const char *zName;            /* Name of the system call */
443   sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
444   sqlite3_syscall_ptr pDefault; /* Default value */
445 } aSyscall[] = {
446 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
447   { "AreFileApisANSI",         (SYSCALL)AreFileApisANSI,         0 },
448 #else
449   { "AreFileApisANSI",         (SYSCALL)0,                       0 },
450 #endif
451 
452 #ifndef osAreFileApisANSI
453 #define osAreFileApisANSI ((BOOL(WINAPI*)(VOID))aSyscall[0].pCurrent)
454 #endif
455 
456 #if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
457   { "CharLowerW",              (SYSCALL)CharLowerW,              0 },
458 #else
459   { "CharLowerW",              (SYSCALL)0,                       0 },
460 #endif
461 
462 #define osCharLowerW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[1].pCurrent)
463 
464 #if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
465   { "CharUpperW",              (SYSCALL)CharUpperW,              0 },
466 #else
467   { "CharUpperW",              (SYSCALL)0,                       0 },
468 #endif
469 
470 #define osCharUpperW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[2].pCurrent)
471 
472   { "CloseHandle",             (SYSCALL)CloseHandle,             0 },
473 
474 #define osCloseHandle ((BOOL(WINAPI*)(HANDLE))aSyscall[3].pCurrent)
475 
476 #if defined(SQLITE_WIN32_HAS_ANSI)
477   { "CreateFileA",             (SYSCALL)CreateFileA,             0 },
478 #else
479   { "CreateFileA",             (SYSCALL)0,                       0 },
480 #endif
481 
482 #define osCreateFileA ((HANDLE(WINAPI*)(LPCSTR,DWORD,DWORD, \
483         LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[4].pCurrent)
484 
485 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
486   { "CreateFileW",             (SYSCALL)CreateFileW,             0 },
487 #else
488   { "CreateFileW",             (SYSCALL)0,                       0 },
489 #endif
490 
491 #define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
492         LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)
493 
494 #if (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_ANSI) && \
495         !defined(SQLITE_OMIT_WAL))
496   { "CreateFileMappingA",      (SYSCALL)CreateFileMappingA,      0 },
497 #else
498   { "CreateFileMappingA",      (SYSCALL)0,                       0 },
499 #endif
500 
501 #define osCreateFileMappingA ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
502         DWORD,DWORD,DWORD,LPCSTR))aSyscall[6].pCurrent)
503 
504 #if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
505         !defined(SQLITE_OMIT_WAL))
506   { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
507 #else
508   { "CreateFileMappingW",      (SYSCALL)0,                       0 },
509 #endif
510 
511 #define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
512         DWORD,DWORD,DWORD,LPCWSTR))aSyscall[7].pCurrent)
513 
514 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
515   { "CreateMutexW",            (SYSCALL)CreateMutexW,            0 },
516 #else
517   { "CreateMutexW",            (SYSCALL)0,                       0 },
518 #endif
519 
520 #define osCreateMutexW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,BOOL, \
521         LPCWSTR))aSyscall[8].pCurrent)
522 
523 #if defined(SQLITE_WIN32_HAS_ANSI)
524   { "DeleteFileA",             (SYSCALL)DeleteFileA,             0 },
525 #else
526   { "DeleteFileA",             (SYSCALL)0,                       0 },
527 #endif
528 
529 #define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[9].pCurrent)
530 
531 #if defined(SQLITE_WIN32_HAS_WIDE)
532   { "DeleteFileW",             (SYSCALL)DeleteFileW,             0 },
533 #else
534   { "DeleteFileW",             (SYSCALL)0,                       0 },
535 #endif
536 
537 #define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[10].pCurrent)
538 
539 #if SQLITE_OS_WINCE
540   { "FileTimeToLocalFileTime", (SYSCALL)FileTimeToLocalFileTime, 0 },
541 #else
542   { "FileTimeToLocalFileTime", (SYSCALL)0,                       0 },
543 #endif
544 
545 #define osFileTimeToLocalFileTime ((BOOL(WINAPI*)(CONST FILETIME*, \
546         LPFILETIME))aSyscall[11].pCurrent)
547 
548 #if SQLITE_OS_WINCE
549   { "FileTimeToSystemTime",    (SYSCALL)FileTimeToSystemTime,    0 },
550 #else
551   { "FileTimeToSystemTime",    (SYSCALL)0,                       0 },
552 #endif
553 
554 #define osFileTimeToSystemTime ((BOOL(WINAPI*)(CONST FILETIME*, \
555         LPSYSTEMTIME))aSyscall[12].pCurrent)
556 
557   { "FlushFileBuffers",        (SYSCALL)FlushFileBuffers,        0 },
558 
559 #define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[13].pCurrent)
560 
561 #if defined(SQLITE_WIN32_HAS_ANSI)
562   { "FormatMessageA",          (SYSCALL)FormatMessageA,          0 },
563 #else
564   { "FormatMessageA",          (SYSCALL)0,                       0 },
565 #endif
566 
567 #define osFormatMessageA ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPSTR, \
568         DWORD,va_list*))aSyscall[14].pCurrent)
569 
570 #if defined(SQLITE_WIN32_HAS_WIDE)
571   { "FormatMessageW",          (SYSCALL)FormatMessageW,          0 },
572 #else
573   { "FormatMessageW",          (SYSCALL)0,                       0 },
574 #endif
575 
576 #define osFormatMessageW ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPWSTR, \
577         DWORD,va_list*))aSyscall[15].pCurrent)
578 
579 #if !defined(SQLITE_OMIT_LOAD_EXTENSION)
580   { "FreeLibrary",             (SYSCALL)FreeLibrary,             0 },
581 #else
582   { "FreeLibrary",             (SYSCALL)0,                       0 },
583 #endif
584 
585 #define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[16].pCurrent)
586 
587   { "GetCurrentProcessId",     (SYSCALL)GetCurrentProcessId,     0 },
588 
589 #define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[17].pCurrent)
590 
591 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
592   { "GetDiskFreeSpaceA",       (SYSCALL)GetDiskFreeSpaceA,       0 },
593 #else
594   { "GetDiskFreeSpaceA",       (SYSCALL)0,                       0 },
595 #endif
596 
597 #define osGetDiskFreeSpaceA ((BOOL(WINAPI*)(LPCSTR,LPDWORD,LPDWORD,LPDWORD, \
598         LPDWORD))aSyscall[18].pCurrent)
599 
600 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
601   { "GetDiskFreeSpaceW",       (SYSCALL)GetDiskFreeSpaceW,       0 },
602 #else
603   { "GetDiskFreeSpaceW",       (SYSCALL)0,                       0 },
604 #endif
605 
606 #define osGetDiskFreeSpaceW ((BOOL(WINAPI*)(LPCWSTR,LPDWORD,LPDWORD,LPDWORD, \
607         LPDWORD))aSyscall[19].pCurrent)
608 
609 #if defined(SQLITE_WIN32_HAS_ANSI)
610   { "GetFileAttributesA",      (SYSCALL)GetFileAttributesA,      0 },
611 #else
612   { "GetFileAttributesA",      (SYSCALL)0,                       0 },
613 #endif
614 
615 #define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[20].pCurrent)
616 
617 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
618   { "GetFileAttributesW",      (SYSCALL)GetFileAttributesW,      0 },
619 #else
620   { "GetFileAttributesW",      (SYSCALL)0,                       0 },
621 #endif
622 
623 #define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[21].pCurrent)
624 
625 #if defined(SQLITE_WIN32_HAS_WIDE)
626   { "GetFileAttributesExW",    (SYSCALL)GetFileAttributesExW,    0 },
627 #else
628   { "GetFileAttributesExW",    (SYSCALL)0,                       0 },
629 #endif
630 
631 #define osGetFileAttributesExW ((BOOL(WINAPI*)(LPCWSTR,GET_FILEEX_INFO_LEVELS, \
632         LPVOID))aSyscall[22].pCurrent)
633 
634 #if !SQLITE_OS_WINRT
635   { "GetFileSize",             (SYSCALL)GetFileSize,             0 },
636 #else
637   { "GetFileSize",             (SYSCALL)0,                       0 },
638 #endif
639 
640 #define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[23].pCurrent)
641 
642 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
643   { "GetFullPathNameA",        (SYSCALL)GetFullPathNameA,        0 },
644 #else
645   { "GetFullPathNameA",        (SYSCALL)0,                       0 },
646 #endif
647 
648 #define osGetFullPathNameA ((DWORD(WINAPI*)(LPCSTR,DWORD,LPSTR, \
649         LPSTR*))aSyscall[24].pCurrent)
650 
651 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
652   { "GetFullPathNameW",        (SYSCALL)GetFullPathNameW,        0 },
653 #else
654   { "GetFullPathNameW",        (SYSCALL)0,                       0 },
655 #endif
656 
657 #define osGetFullPathNameW ((DWORD(WINAPI*)(LPCWSTR,DWORD,LPWSTR, \
658         LPWSTR*))aSyscall[25].pCurrent)
659 
660   { "GetLastError",            (SYSCALL)GetLastError,            0 },
661 
662 #define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[26].pCurrent)
663 
664 #if !defined(SQLITE_OMIT_LOAD_EXTENSION)
665 #if SQLITE_OS_WINCE
666   /* The GetProcAddressA() routine is only available on Windows CE. */
667   { "GetProcAddressA",         (SYSCALL)GetProcAddressA,         0 },
668 #else
669   /* All other Windows platforms expect GetProcAddress() to take
670   ** an ANSI string regardless of the _UNICODE setting */
671   { "GetProcAddressA",         (SYSCALL)GetProcAddress,          0 },
672 #endif
673 #else
674   { "GetProcAddressA",         (SYSCALL)0,                       0 },
675 #endif
676 
677 #define osGetProcAddressA ((FARPROC(WINAPI*)(HMODULE, \
678         LPCSTR))aSyscall[27].pCurrent)
679 
680 #if !SQLITE_OS_WINRT
681   { "GetSystemInfo",           (SYSCALL)GetSystemInfo,           0 },
682 #else
683   { "GetSystemInfo",           (SYSCALL)0,                       0 },
684 #endif
685 
686 #define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[28].pCurrent)
687 
688   { "GetSystemTime",           (SYSCALL)GetSystemTime,           0 },
689 
690 #define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[29].pCurrent)
691 
692 #if !SQLITE_OS_WINCE
693   { "GetSystemTimeAsFileTime", (SYSCALL)GetSystemTimeAsFileTime, 0 },
694 #else
695   { "GetSystemTimeAsFileTime", (SYSCALL)0,                       0 },
696 #endif
697 
698 #define osGetSystemTimeAsFileTime ((VOID(WINAPI*)( \
699         LPFILETIME))aSyscall[30].pCurrent)
700 
701 #if defined(SQLITE_WIN32_HAS_ANSI)
702   { "GetTempPathA",            (SYSCALL)GetTempPathA,            0 },
703 #else
704   { "GetTempPathA",            (SYSCALL)0,                       0 },
705 #endif
706 
707 #define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[31].pCurrent)
708 
709 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
710   { "GetTempPathW",            (SYSCALL)GetTempPathW,            0 },
711 #else
712   { "GetTempPathW",            (SYSCALL)0,                       0 },
713 #endif
714 
715 #define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[32].pCurrent)
716 
717 #if !SQLITE_OS_WINRT
718   { "GetTickCount",            (SYSCALL)GetTickCount,            0 },
719 #else
720   { "GetTickCount",            (SYSCALL)0,                       0 },
721 #endif
722 
723 #define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[33].pCurrent)
724 
725 #if defined(SQLITE_WIN32_HAS_ANSI) && defined(SQLITE_WIN32_GETVERSIONEX) && \
726         SQLITE_WIN32_GETVERSIONEX
727   { "GetVersionExA",           (SYSCALL)GetVersionExA,           0 },
728 #else
729   { "GetVersionExA",           (SYSCALL)0,                       0 },
730 #endif
731 
732 #define osGetVersionExA ((BOOL(WINAPI*)( \
733         LPOSVERSIONINFOA))aSyscall[34].pCurrent)
734 
735 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
736         defined(SQLITE_WIN32_GETVERSIONEX) && SQLITE_WIN32_GETVERSIONEX
737   { "GetVersionExW",           (SYSCALL)GetVersionExW,           0 },
738 #else
739   { "GetVersionExW",           (SYSCALL)0,                       0 },
740 #endif
741 
742 #define osGetVersionExW ((BOOL(WINAPI*)( \
743         LPOSVERSIONINFOW))aSyscall[35].pCurrent)
744 
745   { "HeapAlloc",               (SYSCALL)HeapAlloc,               0 },
746 
747 #define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
748         SIZE_T))aSyscall[36].pCurrent)
749 
750 #if !SQLITE_OS_WINRT
751   { "HeapCreate",              (SYSCALL)HeapCreate,              0 },
752 #else
753   { "HeapCreate",              (SYSCALL)0,                       0 },
754 #endif
755 
756 #define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
757         SIZE_T))aSyscall[37].pCurrent)
758 
759 #if !SQLITE_OS_WINRT
760   { "HeapDestroy",             (SYSCALL)HeapDestroy,             0 },
761 #else
762   { "HeapDestroy",             (SYSCALL)0,                       0 },
763 #endif
764 
765 #define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[38].pCurrent)
766 
767   { "HeapFree",                (SYSCALL)HeapFree,                0 },
768 
769 #define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[39].pCurrent)
770 
771   { "HeapReAlloc",             (SYSCALL)HeapReAlloc,             0 },
772 
773 #define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
774         SIZE_T))aSyscall[40].pCurrent)
775 
776   { "HeapSize",                (SYSCALL)HeapSize,                0 },
777 
778 #define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
779         LPCVOID))aSyscall[41].pCurrent)
780 
781 #if !SQLITE_OS_WINRT
782   { "HeapValidate",            (SYSCALL)HeapValidate,            0 },
783 #else
784   { "HeapValidate",            (SYSCALL)0,                       0 },
785 #endif
786 
787 #define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
788         LPCVOID))aSyscall[42].pCurrent)
789 
790 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
791   { "HeapCompact",             (SYSCALL)HeapCompact,             0 },
792 #else
793   { "HeapCompact",             (SYSCALL)0,                       0 },
794 #endif
795 
796 #define osHeapCompact ((UINT(WINAPI*)(HANDLE,DWORD))aSyscall[43].pCurrent)
797 
798 #if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
799   { "LoadLibraryA",            (SYSCALL)LoadLibraryA,            0 },
800 #else
801   { "LoadLibraryA",            (SYSCALL)0,                       0 },
802 #endif
803 
804 #define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[44].pCurrent)
805 
806 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
807         !defined(SQLITE_OMIT_LOAD_EXTENSION)
808   { "LoadLibraryW",            (SYSCALL)LoadLibraryW,            0 },
809 #else
810   { "LoadLibraryW",            (SYSCALL)0,                       0 },
811 #endif
812 
813 #define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[45].pCurrent)
814 
815 #if !SQLITE_OS_WINRT
816   { "LocalFree",               (SYSCALL)LocalFree,               0 },
817 #else
818   { "LocalFree",               (SYSCALL)0,                       0 },
819 #endif
820 
821 #define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[46].pCurrent)
822 
823 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
824   { "LockFile",                (SYSCALL)LockFile,                0 },
825 #else
826   { "LockFile",                (SYSCALL)0,                       0 },
827 #endif
828 
829 #ifndef osLockFile
830 #define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
831         DWORD))aSyscall[47].pCurrent)
832 #endif
833 
834 #if !SQLITE_OS_WINCE
835   { "LockFileEx",              (SYSCALL)LockFileEx,              0 },
836 #else
837   { "LockFileEx",              (SYSCALL)0,                       0 },
838 #endif
839 
840 #ifndef osLockFileEx
841 #define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
842         LPOVERLAPPED))aSyscall[48].pCurrent)
843 #endif
844 
845 #if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL))
846   { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
847 #else
848   { "MapViewOfFile",           (SYSCALL)0,                       0 },
849 #endif
850 
851 #define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
852         SIZE_T))aSyscall[49].pCurrent)
853 
854   { "MultiByteToWideChar",     (SYSCALL)MultiByteToWideChar,     0 },
855 
856 #define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
857         int))aSyscall[50].pCurrent)
858 
859   { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },
860 
861 #define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
862         LARGE_INTEGER*))aSyscall[51].pCurrent)
863 
864   { "ReadFile",                (SYSCALL)ReadFile,                0 },
865 
866 #define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
867         LPOVERLAPPED))aSyscall[52].pCurrent)
868 
869   { "SetEndOfFile",            (SYSCALL)SetEndOfFile,            0 },
870 
871 #define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[53].pCurrent)
872 
873 #if !SQLITE_OS_WINRT
874   { "SetFilePointer",          (SYSCALL)SetFilePointer,          0 },
875 #else
876   { "SetFilePointer",          (SYSCALL)0,                       0 },
877 #endif
878 
879 #define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
880         DWORD))aSyscall[54].pCurrent)
881 
882 #if !SQLITE_OS_WINRT
883   { "Sleep",                   (SYSCALL)Sleep,                   0 },
884 #else
885   { "Sleep",                   (SYSCALL)0,                       0 },
886 #endif
887 
888 #define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[55].pCurrent)
889 
890   { "SystemTimeToFileTime",    (SYSCALL)SystemTimeToFileTime,    0 },
891 
892 #define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
893         LPFILETIME))aSyscall[56].pCurrent)
894 
895 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
896   { "UnlockFile",              (SYSCALL)UnlockFile,              0 },
897 #else
898   { "UnlockFile",              (SYSCALL)0,                       0 },
899 #endif
900 
901 #ifndef osUnlockFile
902 #define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
903         DWORD))aSyscall[57].pCurrent)
904 #endif
905 
906 #if !SQLITE_OS_WINCE
907   { "UnlockFileEx",            (SYSCALL)UnlockFileEx,            0 },
908 #else
909   { "UnlockFileEx",            (SYSCALL)0,                       0 },
910 #endif
911 
912 #define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
913         LPOVERLAPPED))aSyscall[58].pCurrent)
914 
915 #if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL)
916   { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
917 #else
918   { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
919 #endif
920 
921 #define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[59].pCurrent)
922 
923   { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },
924 
925 #define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
926         LPCSTR,LPBOOL))aSyscall[60].pCurrent)
927 
928   { "WriteFile",               (SYSCALL)WriteFile,               0 },
929 
930 #define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
931         LPOVERLAPPED))aSyscall[61].pCurrent)
932 
933 #if SQLITE_OS_WINRT
934   { "CreateEventExW",          (SYSCALL)CreateEventExW,          0 },
935 #else
936   { "CreateEventExW",          (SYSCALL)0,                       0 },
937 #endif
938 
939 #define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
940         DWORD,DWORD))aSyscall[62].pCurrent)
941 
942 #if !SQLITE_OS_WINRT
943   { "WaitForSingleObject",     (SYSCALL)WaitForSingleObject,     0 },
944 #else
945   { "WaitForSingleObject",     (SYSCALL)0,                       0 },
946 #endif
947 
948 #define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
949         DWORD))aSyscall[63].pCurrent)
950 
951 #if SQLITE_OS_WINRT
952   { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
953 #else
954   { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
955 #endif
956 
957 #define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
958         BOOL))aSyscall[64].pCurrent)
959 
960 #if SQLITE_OS_WINRT
961   { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
962 #else
963   { "SetFilePointerEx",        (SYSCALL)0,                       0 },
964 #endif
965 
966 #define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
967         PLARGE_INTEGER,DWORD))aSyscall[65].pCurrent)
968 
969 #if SQLITE_OS_WINRT
970   { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
971 #else
972   { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
973 #endif
974 
975 #define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
976         FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[66].pCurrent)
977 
978 #if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
979   { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
980 #else
981   { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
982 #endif
983 
984 #define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
985         SIZE_T))aSyscall[67].pCurrent)
986 
987 #if SQLITE_OS_WINRT
988   { "CreateFile2",             (SYSCALL)CreateFile2,             0 },
989 #else
990   { "CreateFile2",             (SYSCALL)0,                       0 },
991 #endif
992 
993 #define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
994         LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[68].pCurrent)
995 
996 #if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
997   { "LoadPackagedLibrary",     (SYSCALL)LoadPackagedLibrary,     0 },
998 #else
999   { "LoadPackagedLibrary",     (SYSCALL)0,                       0 },
1000 #endif
1001 
1002 #define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
1003         DWORD))aSyscall[69].pCurrent)
1004 
1005 #if SQLITE_OS_WINRT
1006   { "GetTickCount64",          (SYSCALL)GetTickCount64,          0 },
1007 #else
1008   { "GetTickCount64",          (SYSCALL)0,                       0 },
1009 #endif
1010 
1011 #define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[70].pCurrent)
1012 
1013 #if SQLITE_OS_WINRT
1014   { "GetNativeSystemInfo",     (SYSCALL)GetNativeSystemInfo,     0 },
1015 #else
1016   { "GetNativeSystemInfo",     (SYSCALL)0,                       0 },
1017 #endif
1018 
1019 #define osGetNativeSystemInfo ((VOID(WINAPI*)( \
1020         LPSYSTEM_INFO))aSyscall[71].pCurrent)
1021 
1022 #if defined(SQLITE_WIN32_HAS_ANSI)
1023   { "OutputDebugStringA",      (SYSCALL)OutputDebugStringA,      0 },
1024 #else
1025   { "OutputDebugStringA",      (SYSCALL)0,                       0 },
1026 #endif
1027 
1028 #define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[72].pCurrent)
1029 
1030 #if defined(SQLITE_WIN32_HAS_WIDE)
1031   { "OutputDebugStringW",      (SYSCALL)OutputDebugStringW,      0 },
1032 #else
1033   { "OutputDebugStringW",      (SYSCALL)0,                       0 },
1034 #endif
1035 
1036 #define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[73].pCurrent)
1037 
1038   { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },
1039 
1040 #define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[74].pCurrent)
1041 
1042 #if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
1043   { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
1044 #else
1045   { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
1046 #endif
1047 
1048 #define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
1049         LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[75].pCurrent)
1050 
1051 }; /* End of the overrideable system calls */
1052 
1053 /*
1054 ** This is the xSetSystemCall() method of sqlite3_vfs for all of the
1055 ** "win32" VFSes.  Return SQLITE_OK opon successfully updating the
1056 ** system call pointer, or SQLITE_NOTFOUND if there is no configurable
1057 ** system call named zName.
1058 */
1059 static int winSetSystemCall(
1060   sqlite3_vfs *pNotUsed,        /* The VFS pointer.  Not used */
1061   const char *zName,            /* Name of system call to override */
1062   sqlite3_syscall_ptr pNewFunc  /* Pointer to new system call value */
1063 ){
1064   unsigned int i;
1065   int rc = SQLITE_NOTFOUND;
1066 
1067   UNUSED_PARAMETER(pNotUsed);
1068   if( zName==0 ){
1069     /* If no zName is given, restore all system calls to their default
1070     ** settings and return NULL
1071     */
1072     rc = SQLITE_OK;
1073     for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1074       if( aSyscall[i].pDefault ){
1075         aSyscall[i].pCurrent = aSyscall[i].pDefault;
1076       }
1077     }
1078   }else{
1079     /* If zName is specified, operate on only the one system call
1080     ** specified.
1081     */
1082     for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1083       if( strcmp(zName, aSyscall[i].zName)==0 ){
1084         if( aSyscall[i].pDefault==0 ){
1085           aSyscall[i].pDefault = aSyscall[i].pCurrent;
1086         }
1087         rc = SQLITE_OK;
1088         if( pNewFunc==0 ) pNewFunc = aSyscall[i].pDefault;
1089         aSyscall[i].pCurrent = pNewFunc;
1090         break;
1091       }
1092     }
1093   }
1094   return rc;
1095 }
1096 
1097 /*
1098 ** Return the value of a system call.  Return NULL if zName is not a
1099 ** recognized system call name.  NULL is also returned if the system call
1100 ** is currently undefined.
1101 */
1102 static sqlite3_syscall_ptr winGetSystemCall(
1103   sqlite3_vfs *pNotUsed,
1104   const char *zName
1105 ){
1106   unsigned int i;
1107 
1108   UNUSED_PARAMETER(pNotUsed);
1109   for(i=0; i<sizeof(aSyscall)/sizeof(aSyscall[0]); i++){
1110     if( strcmp(zName, aSyscall[i].zName)==0 ) return aSyscall[i].pCurrent;
1111   }
1112   return 0;
1113 }
1114 
1115 /*
1116 ** Return the name of the first system call after zName.  If zName==NULL
1117 ** then return the name of the first system call.  Return NULL if zName
1118 ** is the last system call or if zName is not the name of a valid
1119 ** system call.
1120 */
1121 static const char *winNextSystemCall(sqlite3_vfs *p, const char *zName){
1122   int i = -1;
1123 
1124   UNUSED_PARAMETER(p);
1125   if( zName ){
1126     for(i=0; i<ArraySize(aSyscall)-1; i++){
1127       if( strcmp(zName, aSyscall[i].zName)==0 ) break;
1128     }
1129   }
1130   for(i++; i<ArraySize(aSyscall); i++){
1131     if( aSyscall[i].pCurrent!=0 ) return aSyscall[i].zName;
1132   }
1133   return 0;
1134 }
1135 
1136 #ifdef SQLITE_WIN32_MALLOC
1137 /*
1138 ** If a Win32 native heap has been configured, this function will attempt to
1139 ** compact it.  Upon success, SQLITE_OK will be returned.  Upon failure, one
1140 ** of SQLITE_NOMEM, SQLITE_ERROR, or SQLITE_NOTFOUND will be returned.  The
1141 ** "pnLargest" argument, if non-zero, will be used to return the size of the
1142 ** largest committed free block in the heap, in bytes.
1143 */
1144 int sqlite3_win32_compact_heap(LPUINT pnLargest){
1145   int rc = SQLITE_OK;
1146   UINT nLargest = 0;
1147   HANDLE hHeap;
1148 
1149   winMemAssertMagic();
1150   hHeap = winMemGetHeap();
1151   assert( hHeap!=0 );
1152   assert( hHeap!=INVALID_HANDLE_VALUE );
1153 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1154   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1155 #endif
1156 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
1157   if( (nLargest=osHeapCompact(hHeap, SQLITE_WIN32_HEAP_FLAGS))==0 ){
1158     DWORD lastErrno = osGetLastError();
1159     if( lastErrno==NO_ERROR ){
1160       sqlite3_log(SQLITE_NOMEM, "failed to HeapCompact (no space), heap=%p",
1161                   (void*)hHeap);
1162       rc = SQLITE_NOMEM;
1163     }else{
1164       sqlite3_log(SQLITE_ERROR, "failed to HeapCompact (%lu), heap=%p",
1165                   osGetLastError(), (void*)hHeap);
1166       rc = SQLITE_ERROR;
1167     }
1168   }
1169 #else
1170   sqlite3_log(SQLITE_NOTFOUND, "failed to HeapCompact, heap=%p",
1171               (void*)hHeap);
1172   rc = SQLITE_NOTFOUND;
1173 #endif
1174   if( pnLargest ) *pnLargest = nLargest;
1175   return rc;
1176 }
1177 
1178 /*
1179 ** If a Win32 native heap has been configured, this function will attempt to
1180 ** destroy and recreate it.  If the Win32 native heap is not isolated and/or
1181 ** the sqlite3_memory_used() function does not return zero, SQLITE_BUSY will
1182 ** be returned and no changes will be made to the Win32 native heap.
1183 */
1184 int sqlite3_win32_reset_heap(){
1185   int rc;
1186   MUTEX_LOGIC( sqlite3_mutex *pMaster; ) /* The main static mutex */
1187   MUTEX_LOGIC( sqlite3_mutex *pMem; )    /* The memsys static mutex */
1188   MUTEX_LOGIC( pMaster = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER); )
1189   MUTEX_LOGIC( pMem = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM); )
1190   sqlite3_mutex_enter(pMaster);
1191   sqlite3_mutex_enter(pMem);
1192   winMemAssertMagic();
1193   if( winMemGetHeap()!=NULL && winMemGetOwned() && sqlite3_memory_used()==0 ){
1194     /*
1195     ** At this point, there should be no outstanding memory allocations on
1196     ** the heap.  Also, since both the master and memsys locks are currently
1197     ** being held by us, no other function (i.e. from another thread) should
1198     ** be able to even access the heap.  Attempt to destroy and recreate our
1199     ** isolated Win32 native heap now.
1200     */
1201     assert( winMemGetHeap()!=NULL );
1202     assert( winMemGetOwned() );
1203     assert( sqlite3_memory_used()==0 );
1204     winMemShutdown(winMemGetDataPtr());
1205     assert( winMemGetHeap()==NULL );
1206     assert( !winMemGetOwned() );
1207     assert( sqlite3_memory_used()==0 );
1208     rc = winMemInit(winMemGetDataPtr());
1209     assert( rc!=SQLITE_OK || winMemGetHeap()!=NULL );
1210     assert( rc!=SQLITE_OK || winMemGetOwned() );
1211     assert( rc!=SQLITE_OK || sqlite3_memory_used()==0 );
1212   }else{
1213     /*
1214     ** The Win32 native heap cannot be modified because it may be in use.
1215     */
1216     rc = SQLITE_BUSY;
1217   }
1218   sqlite3_mutex_leave(pMem);
1219   sqlite3_mutex_leave(pMaster);
1220   return rc;
1221 }
1222 #endif /* SQLITE_WIN32_MALLOC */
1223 
1224 /*
1225 ** This function outputs the specified (ANSI) string to the Win32 debugger
1226 ** (if available).
1227 */
1228 
1229 void sqlite3_win32_write_debug(const char *zBuf, int nBuf){
1230   char zDbgBuf[SQLITE_WIN32_DBG_BUF_SIZE];
1231   int nMin = MIN(nBuf, (SQLITE_WIN32_DBG_BUF_SIZE - 1)); /* may be negative. */
1232   if( nMin<-1 ) nMin = -1; /* all negative values become -1. */
1233   assert( nMin==-1 || nMin==0 || nMin<SQLITE_WIN32_DBG_BUF_SIZE );
1234 #if defined(SQLITE_WIN32_HAS_ANSI)
1235   if( nMin>0 ){
1236     memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1237     memcpy(zDbgBuf, zBuf, nMin);
1238     osOutputDebugStringA(zDbgBuf);
1239   }else{
1240     osOutputDebugStringA(zBuf);
1241   }
1242 #elif defined(SQLITE_WIN32_HAS_WIDE)
1243   memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1244   if ( osMultiByteToWideChar(
1245           osAreFileApisANSI() ? CP_ACP : CP_OEMCP, 0, zBuf,
1246           nMin, (LPWSTR)zDbgBuf, SQLITE_WIN32_DBG_BUF_SIZE/sizeof(WCHAR))<=0 ){
1247     return;
1248   }
1249   osOutputDebugStringW((LPCWSTR)zDbgBuf);
1250 #else
1251   if( nMin>0 ){
1252     memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
1253     memcpy(zDbgBuf, zBuf, nMin);
1254     fprintf(stderr, "%s", zDbgBuf);
1255   }else{
1256     fprintf(stderr, "%s", zBuf);
1257   }
1258 #endif
1259 }
1260 
1261 /*
1262 ** The following routine suspends the current thread for at least ms
1263 ** milliseconds.  This is equivalent to the Win32 Sleep() interface.
1264 */
1265 #if SQLITE_OS_WINRT
1266 static HANDLE sleepObj = NULL;
1267 #endif
1268 
1269 void sqlite3_win32_sleep(DWORD milliseconds){
1270 #if SQLITE_OS_WINRT
1271   if ( sleepObj==NULL ){
1272     sleepObj = osCreateEventExW(NULL, NULL, CREATE_EVENT_MANUAL_RESET,
1273                                 SYNCHRONIZE);
1274   }
1275   assert( sleepObj!=NULL );
1276   osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
1277 #else
1278   osSleep(milliseconds);
1279 #endif
1280 }
1281 
1282 /*
1283 ** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
1284 ** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
1285 **
1286 ** Here is an interesting observation:  Win95, Win98, and WinME lack
1287 ** the LockFileEx() API.  But we can still statically link against that
1288 ** API as long as we don't call it when running Win95/98/ME.  A call to
1289 ** this routine is used to determine if the host is Win95/98/ME or
1290 ** WinNT/2K/XP so that we will know whether or not we can safely call
1291 ** the LockFileEx() API.
1292 */
1293 
1294 #if !defined(SQLITE_WIN32_GETVERSIONEX) || !SQLITE_WIN32_GETVERSIONEX
1295 # define osIsNT()  (1)
1296 #elif SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
1297 # define osIsNT()  (1)
1298 #elif !defined(SQLITE_WIN32_HAS_WIDE)
1299 # define osIsNT()  (0)
1300 #else
1301   static int osIsNT(void){
1302     if( sqlite3_os_type==0 ){
1303 #if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WIN8
1304       OSVERSIONINFOW sInfo;
1305       sInfo.dwOSVersionInfoSize = sizeof(sInfo);
1306       osGetVersionExW(&sInfo);
1307 #else
1308       OSVERSIONINFOA sInfo;
1309       sInfo.dwOSVersionInfoSize = sizeof(sInfo);
1310       osGetVersionExA(&sInfo);
1311 #endif
1312       sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
1313     }
1314     return sqlite3_os_type==2;
1315   }
1316 #endif
1317 
1318 #ifdef SQLITE_WIN32_MALLOC
1319 /*
1320 ** Allocate nBytes of memory.
1321 */
1322 static void *winMemMalloc(int nBytes){
1323   HANDLE hHeap;
1324   void *p;
1325 
1326   winMemAssertMagic();
1327   hHeap = winMemGetHeap();
1328   assert( hHeap!=0 );
1329   assert( hHeap!=INVALID_HANDLE_VALUE );
1330 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1331   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1332 #endif
1333   assert( nBytes>=0 );
1334   p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
1335   if( !p ){
1336     sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%lu), heap=%p",
1337                 nBytes, osGetLastError(), (void*)hHeap);
1338   }
1339   return p;
1340 }
1341 
1342 /*
1343 ** Free memory.
1344 */
1345 static void winMemFree(void *pPrior){
1346   HANDLE hHeap;
1347 
1348   winMemAssertMagic();
1349   hHeap = winMemGetHeap();
1350   assert( hHeap!=0 );
1351   assert( hHeap!=INVALID_HANDLE_VALUE );
1352 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1353   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
1354 #endif
1355   if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
1356   if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
1357     sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%lu), heap=%p",
1358                 pPrior, osGetLastError(), (void*)hHeap);
1359   }
1360 }
1361 
1362 /*
1363 ** Change the size of an existing memory allocation
1364 */
1365 static void *winMemRealloc(void *pPrior, int nBytes){
1366   HANDLE hHeap;
1367   void *p;
1368 
1369   winMemAssertMagic();
1370   hHeap = winMemGetHeap();
1371   assert( hHeap!=0 );
1372   assert( hHeap!=INVALID_HANDLE_VALUE );
1373 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1374   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
1375 #endif
1376   assert( nBytes>=0 );
1377   if( !pPrior ){
1378     p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
1379   }else{
1380     p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
1381   }
1382   if( !p ){
1383     sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%lu), heap=%p",
1384                 pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
1385                 (void*)hHeap);
1386   }
1387   return p;
1388 }
1389 
1390 /*
1391 ** Return the size of an outstanding allocation, in bytes.
1392 */
1393 static int winMemSize(void *p){
1394   HANDLE hHeap;
1395   SIZE_T n;
1396 
1397   winMemAssertMagic();
1398   hHeap = winMemGetHeap();
1399   assert( hHeap!=0 );
1400   assert( hHeap!=INVALID_HANDLE_VALUE );
1401 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1402   assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, p) );
1403 #endif
1404   if( !p ) return 0;
1405   n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
1406   if( n==(SIZE_T)-1 ){
1407     sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%lu), heap=%p",
1408                 p, osGetLastError(), (void*)hHeap);
1409     return 0;
1410   }
1411   return (int)n;
1412 }
1413 
1414 /*
1415 ** Round up a request size to the next valid allocation size.
1416 */
1417 static int winMemRoundup(int n){
1418   return n;
1419 }
1420 
1421 /*
1422 ** Initialize this module.
1423 */
1424 static int winMemInit(void *pAppData){
1425   winMemData *pWinMemData = (winMemData *)pAppData;
1426 
1427   if( !pWinMemData ) return SQLITE_ERROR;
1428   assert( pWinMemData->magic1==WINMEM_MAGIC1 );
1429   assert( pWinMemData->magic2==WINMEM_MAGIC2 );
1430 
1431 #if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
1432   if( !pWinMemData->hHeap ){
1433     DWORD dwInitialSize = SQLITE_WIN32_HEAP_INIT_SIZE;
1434     DWORD dwMaximumSize = (DWORD)sqlite3GlobalConfig.nHeap;
1435     if( dwMaximumSize==0 ){
1436       dwMaximumSize = SQLITE_WIN32_HEAP_MAX_SIZE;
1437     }else if( dwInitialSize>dwMaximumSize ){
1438       dwInitialSize = dwMaximumSize;
1439     }
1440     pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
1441                                       dwInitialSize, dwMaximumSize);
1442     if( !pWinMemData->hHeap ){
1443       sqlite3_log(SQLITE_NOMEM,
1444           "failed to HeapCreate (%lu), flags=%u, initSize=%lu, maxSize=%lu",
1445           osGetLastError(), SQLITE_WIN32_HEAP_FLAGS, dwInitialSize,
1446           dwMaximumSize);
1447       return SQLITE_NOMEM;
1448     }
1449     pWinMemData->bOwned = TRUE;
1450     assert( pWinMemData->bOwned );
1451   }
1452 #else
1453   pWinMemData->hHeap = osGetProcessHeap();
1454   if( !pWinMemData->hHeap ){
1455     sqlite3_log(SQLITE_NOMEM,
1456         "failed to GetProcessHeap (%lu)", osGetLastError());
1457     return SQLITE_NOMEM;
1458   }
1459   pWinMemData->bOwned = FALSE;
1460   assert( !pWinMemData->bOwned );
1461 #endif
1462   assert( pWinMemData->hHeap!=0 );
1463   assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
1464 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1465   assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1466 #endif
1467   return SQLITE_OK;
1468 }
1469 
1470 /*
1471 ** Deinitialize this module.
1472 */
1473 static void winMemShutdown(void *pAppData){
1474   winMemData *pWinMemData = (winMemData *)pAppData;
1475 
1476   if( !pWinMemData ) return;
1477   assert( pWinMemData->magic1==WINMEM_MAGIC1 );
1478   assert( pWinMemData->magic2==WINMEM_MAGIC2 );
1479 
1480   if( pWinMemData->hHeap ){
1481     assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
1482 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
1483     assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
1484 #endif
1485     if( pWinMemData->bOwned ){
1486       if( !osHeapDestroy(pWinMemData->hHeap) ){
1487         sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%lu), heap=%p",
1488                     osGetLastError(), (void*)pWinMemData->hHeap);
1489       }
1490       pWinMemData->bOwned = FALSE;
1491     }
1492     pWinMemData->hHeap = NULL;
1493   }
1494 }
1495 
1496 /*
1497 ** Populate the low-level memory allocation function pointers in
1498 ** sqlite3GlobalConfig.m with pointers to the routines in this file. The
1499 ** arguments specify the block of memory to manage.
1500 **
1501 ** This routine is only called by sqlite3_config(), and therefore
1502 ** is not required to be threadsafe (it is not).
1503 */
1504 const sqlite3_mem_methods *sqlite3MemGetWin32(void){
1505   static const sqlite3_mem_methods winMemMethods = {
1506     winMemMalloc,
1507     winMemFree,
1508     winMemRealloc,
1509     winMemSize,
1510     winMemRoundup,
1511     winMemInit,
1512     winMemShutdown,
1513     &win_mem_data
1514   };
1515   return &winMemMethods;
1516 }
1517 
1518 void sqlite3MemSetDefault(void){
1519   sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetWin32());
1520 }
1521 #endif /* SQLITE_WIN32_MALLOC */
1522 
1523 /*
1524 ** Convert a UTF-8 string to Microsoft Unicode (UTF-16?).
1525 **
1526 ** Space to hold the returned string is obtained from malloc.
1527 */
1528 static LPWSTR winUtf8ToUnicode(const char *zFilename){
1529   int nChar;
1530   LPWSTR zWideFilename;
1531 
1532   nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
1533   if( nChar==0 ){
1534     return 0;
1535   }
1536   zWideFilename = sqlite3MallocZero( nChar*sizeof(zWideFilename[0]) );
1537   if( zWideFilename==0 ){
1538     return 0;
1539   }
1540   nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename,
1541                                 nChar);
1542   if( nChar==0 ){
1543     sqlite3_free(zWideFilename);
1544     zWideFilename = 0;
1545   }
1546   return zWideFilename;
1547 }
1548 
1549 /*
1550 ** Convert Microsoft Unicode to UTF-8.  Space to hold the returned string is
1551 ** obtained from sqlite3_malloc().
1552 */
1553 static char *winUnicodeToUtf8(LPCWSTR zWideFilename){
1554   int nByte;
1555   char *zFilename;
1556 
1557   nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
1558   if( nByte == 0 ){
1559     return 0;
1560   }
1561   zFilename = sqlite3MallocZero( nByte );
1562   if( zFilename==0 ){
1563     return 0;
1564   }
1565   nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
1566                                 0, 0);
1567   if( nByte == 0 ){
1568     sqlite3_free(zFilename);
1569     zFilename = 0;
1570   }
1571   return zFilename;
1572 }
1573 
1574 /*
1575 ** Convert an ANSI string to Microsoft Unicode, based on the
1576 ** current codepage settings for file apis.
1577 **
1578 ** Space to hold the returned string is obtained
1579 ** from sqlite3_malloc.
1580 */
1581 static LPWSTR winMbcsToUnicode(const char *zFilename){
1582   int nByte;
1583   LPWSTR zMbcsFilename;
1584   int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
1585 
1586   nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, NULL,
1587                                 0)*sizeof(WCHAR);
1588   if( nByte==0 ){
1589     return 0;
1590   }
1591   zMbcsFilename = sqlite3MallocZero( nByte*sizeof(zMbcsFilename[0]) );
1592   if( zMbcsFilename==0 ){
1593     return 0;
1594   }
1595   nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename,
1596                                 nByte);
1597   if( nByte==0 ){
1598     sqlite3_free(zMbcsFilename);
1599     zMbcsFilename = 0;
1600   }
1601   return zMbcsFilename;
1602 }
1603 
1604 /*
1605 ** Convert Microsoft Unicode to multi-byte character string, based on the
1606 ** user's ANSI codepage.
1607 **
1608 ** Space to hold the returned string is obtained from
1609 ** sqlite3_malloc().
1610 */
1611 static char *winUnicodeToMbcs(LPCWSTR zWideFilename){
1612   int nByte;
1613   char *zFilename;
1614   int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
1615 
1616   nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
1617   if( nByte == 0 ){
1618     return 0;
1619   }
1620   zFilename = sqlite3MallocZero( nByte );
1621   if( zFilename==0 ){
1622     return 0;
1623   }
1624   nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename,
1625                                 nByte, 0, 0);
1626   if( nByte == 0 ){
1627     sqlite3_free(zFilename);
1628     zFilename = 0;
1629   }
1630   return zFilename;
1631 }
1632 
1633 /*
1634 ** Convert multibyte character string to UTF-8.  Space to hold the
1635 ** returned string is obtained from sqlite3_malloc().
1636 */
1637 char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){
1638   char *zFilenameUtf8;
1639   LPWSTR zTmpWide;
1640 
1641   zTmpWide = winMbcsToUnicode(zFilename);
1642   if( zTmpWide==0 ){
1643     return 0;
1644   }
1645   zFilenameUtf8 = winUnicodeToUtf8(zTmpWide);
1646   sqlite3_free(zTmpWide);
1647   return zFilenameUtf8;
1648 }
1649 
1650 /*
1651 ** Convert UTF-8 to multibyte character string.  Space to hold the
1652 ** returned string is obtained from sqlite3_malloc().
1653 */
1654 char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){
1655   char *zFilenameMbcs;
1656   LPWSTR zTmpWide;
1657 
1658   zTmpWide = winUtf8ToUnicode(zFilename);
1659   if( zTmpWide==0 ){
1660     return 0;
1661   }
1662   zFilenameMbcs = winUnicodeToMbcs(zTmpWide);
1663   sqlite3_free(zTmpWide);
1664   return zFilenameMbcs;
1665 }
1666 
1667 /*
1668 ** This function sets the data directory or the temporary directory based on
1669 ** the provided arguments.  The type argument must be 1 in order to set the
1670 ** data directory or 2 in order to set the temporary directory.  The zValue
1671 ** argument is the name of the directory to use.  The return value will be
1672 ** SQLITE_OK if successful.
1673 */
1674 int sqlite3_win32_set_directory(DWORD type, LPCWSTR zValue){
1675   char **ppDirectory = 0;
1676 #ifndef SQLITE_OMIT_AUTOINIT
1677   int rc = sqlite3_initialize();
1678   if( rc ) return rc;
1679 #endif
1680   if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
1681     ppDirectory = &sqlite3_data_directory;
1682   }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
1683     ppDirectory = &sqlite3_temp_directory;
1684   }
1685   assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
1686           || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
1687   );
1688   assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
1689   if( ppDirectory ){
1690     char *zValueUtf8 = 0;
1691     if( zValue && zValue[0] ){
1692       zValueUtf8 = winUnicodeToUtf8(zValue);
1693       if ( zValueUtf8==0 ){
1694         return SQLITE_NOMEM;
1695       }
1696     }
1697     sqlite3_free(*ppDirectory);
1698     *ppDirectory = zValueUtf8;
1699     return SQLITE_OK;
1700   }
1701   return SQLITE_ERROR;
1702 }
1703 
1704 /*
1705 ** The return value of winGetLastErrorMsg
1706 ** is zero if the error message fits in the buffer, or non-zero
1707 ** otherwise (if the message was truncated).
1708 */
1709 static int winGetLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
1710   /* FormatMessage returns 0 on failure.  Otherwise it
1711   ** returns the number of TCHARs written to the output
1712   ** buffer, excluding the terminating null char.
1713   */
1714   DWORD dwLen = 0;
1715   char *zOut = 0;
1716 
1717   if( osIsNT() ){
1718 #if SQLITE_OS_WINRT
1719     WCHAR zTempWide[SQLITE_WIN32_MAX_ERRMSG_CHARS+1];
1720     dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
1721                              FORMAT_MESSAGE_IGNORE_INSERTS,
1722                              NULL,
1723                              lastErrno,
1724                              0,
1725                              zTempWide,
1726                              SQLITE_WIN32_MAX_ERRMSG_CHARS,
1727                              0);
1728 #else
1729     LPWSTR zTempWide = NULL;
1730     dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
1731                              FORMAT_MESSAGE_FROM_SYSTEM |
1732                              FORMAT_MESSAGE_IGNORE_INSERTS,
1733                              NULL,
1734                              lastErrno,
1735                              0,
1736                              (LPWSTR) &zTempWide,
1737                              0,
1738                              0);
1739 #endif
1740     if( dwLen > 0 ){
1741       /* allocate a buffer and convert to UTF8 */
1742       sqlite3BeginBenignMalloc();
1743       zOut = winUnicodeToUtf8(zTempWide);
1744       sqlite3EndBenignMalloc();
1745 #if !SQLITE_OS_WINRT
1746       /* free the system buffer allocated by FormatMessage */
1747       osLocalFree(zTempWide);
1748 #endif
1749     }
1750   }
1751 #ifdef SQLITE_WIN32_HAS_ANSI
1752   else{
1753     char *zTemp = NULL;
1754     dwLen = osFormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
1755                              FORMAT_MESSAGE_FROM_SYSTEM |
1756                              FORMAT_MESSAGE_IGNORE_INSERTS,
1757                              NULL,
1758                              lastErrno,
1759                              0,
1760                              (LPSTR) &zTemp,
1761                              0,
1762                              0);
1763     if( dwLen > 0 ){
1764       /* allocate a buffer and convert to UTF8 */
1765       sqlite3BeginBenignMalloc();
1766       zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
1767       sqlite3EndBenignMalloc();
1768       /* free the system buffer allocated by FormatMessage */
1769       osLocalFree(zTemp);
1770     }
1771   }
1772 #endif
1773   if( 0 == dwLen ){
1774     sqlite3_snprintf(nBuf, zBuf, "OsError 0x%lx (%lu)", lastErrno, lastErrno);
1775   }else{
1776     /* copy a maximum of nBuf chars to output buffer */
1777     sqlite3_snprintf(nBuf, zBuf, "%s", zOut);
1778     /* free the UTF8 buffer */
1779     sqlite3_free(zOut);
1780   }
1781   return 0;
1782 }
1783 
1784 /*
1785 **
1786 ** This function - winLogErrorAtLine() - is only ever called via the macro
1787 ** winLogError().
1788 **
1789 ** This routine is invoked after an error occurs in an OS function.
1790 ** It logs a message using sqlite3_log() containing the current value of
1791 ** error code and, if possible, the human-readable equivalent from
1792 ** FormatMessage.
1793 **
1794 ** The first argument passed to the macro should be the error code that
1795 ** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN).
1796 ** The two subsequent arguments should be the name of the OS function that
1797 ** failed and the associated file-system path, if any.
1798 */
1799 #define winLogError(a,b,c,d)   winLogErrorAtLine(a,b,c,d,__LINE__)
1800 static int winLogErrorAtLine(
1801   int errcode,                    /* SQLite error code */
1802   DWORD lastErrno,                /* Win32 last error */
1803   const char *zFunc,              /* Name of OS function that failed */
1804   const char *zPath,              /* File path associated with error */
1805   int iLine                       /* Source line number where error occurred */
1806 ){
1807   char zMsg[500];                 /* Human readable error text */
1808   int i;                          /* Loop counter */
1809 
1810   zMsg[0] = 0;
1811   winGetLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
1812   assert( errcode!=SQLITE_OK );
1813   if( zPath==0 ) zPath = "";
1814   for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
1815   zMsg[i] = 0;
1816   sqlite3_log(errcode,
1817       "os_win.c:%d: (%lu) %s(%s) - %s",
1818       iLine, lastErrno, zFunc, zPath, zMsg
1819   );
1820 
1821   return errcode;
1822 }
1823 
1824 /*
1825 ** The number of times that a ReadFile(), WriteFile(), and DeleteFile()
1826 ** will be retried following a locking error - probably caused by
1827 ** antivirus software.  Also the initial delay before the first retry.
1828 ** The delay increases linearly with each retry.
1829 */
1830 #ifndef SQLITE_WIN32_IOERR_RETRY
1831 # define SQLITE_WIN32_IOERR_RETRY 10
1832 #endif
1833 #ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
1834 # define SQLITE_WIN32_IOERR_RETRY_DELAY 25
1835 #endif
1836 static int winIoerrRetry = SQLITE_WIN32_IOERR_RETRY;
1837 static int winIoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;
1838 
1839 /*
1840 ** If a ReadFile() or WriteFile() error occurs, invoke this routine
1841 ** to see if it should be retried.  Return TRUE to retry.  Return FALSE
1842 ** to give up with an error.
1843 */
1844 static int winRetryIoerr(int *pnRetry, DWORD *pError){
1845   DWORD e = osGetLastError();
1846   if( *pnRetry>=winIoerrRetry ){
1847     if( pError ){
1848       *pError = e;
1849     }
1850     return 0;
1851   }
1852   if( e==ERROR_ACCESS_DENIED ||
1853       e==ERROR_LOCK_VIOLATION ||
1854       e==ERROR_SHARING_VIOLATION ){
1855     sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
1856     ++*pnRetry;
1857     return 1;
1858   }
1859   if( pError ){
1860     *pError = e;
1861   }
1862   return 0;
1863 }
1864 
1865 /*
1866 ** Log a I/O error retry episode.
1867 */
1868 static void winLogIoerr(int nRetry){
1869   if( nRetry ){
1870     sqlite3_log(SQLITE_IOERR,
1871       "delayed %dms for lock/sharing conflict",
1872       winIoerrRetryDelay*nRetry*(nRetry+1)/2
1873     );
1874   }
1875 }
1876 
1877 #if SQLITE_OS_WINCE
1878 /*************************************************************************
1879 ** This section contains code for WinCE only.
1880 */
1881 #if !defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API
1882 /*
1883 ** The MSVC CRT on Windows CE may not have a localtime() function.  So
1884 ** create a substitute.
1885 */
1886 #include <time.h>
1887 struct tm *__cdecl localtime(const time_t *t)
1888 {
1889   static struct tm y;
1890   FILETIME uTm, lTm;
1891   SYSTEMTIME pTm;
1892   sqlite3_int64 t64;
1893   t64 = *t;
1894   t64 = (t64 + 11644473600)*10000000;
1895   uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
1896   uTm.dwHighDateTime= (DWORD)(t64 >> 32);
1897   osFileTimeToLocalFileTime(&uTm,&lTm);
1898   osFileTimeToSystemTime(&lTm,&pTm);
1899   y.tm_year = pTm.wYear - 1900;
1900   y.tm_mon = pTm.wMonth - 1;
1901   y.tm_wday = pTm.wDayOfWeek;
1902   y.tm_mday = pTm.wDay;
1903   y.tm_hour = pTm.wHour;
1904   y.tm_min = pTm.wMinute;
1905   y.tm_sec = pTm.wSecond;
1906   return &y;
1907 }
1908 #endif
1909 
1910 #define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
1911 
1912 /*
1913 ** Acquire a lock on the handle h
1914 */
1915 static void winceMutexAcquire(HANDLE h){
1916    DWORD dwErr;
1917    do {
1918      dwErr = osWaitForSingleObject(h, INFINITE);
1919    } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
1920 }
1921 /*
1922 ** Release a lock acquired by winceMutexAcquire()
1923 */
1924 #define winceMutexRelease(h) ReleaseMutex(h)
1925 
1926 /*
1927 ** Create the mutex and shared memory used for locking in the file
1928 ** descriptor pFile
1929 */
1930 static int winceCreateLock(const char *zFilename, winFile *pFile){
1931   LPWSTR zTok;
1932   LPWSTR zName;
1933   DWORD lastErrno;
1934   BOOL bLogged = FALSE;
1935   BOOL bInit = TRUE;
1936 
1937   zName = winUtf8ToUnicode(zFilename);
1938   if( zName==0 ){
1939     /* out of memory */
1940     return SQLITE_IOERR_NOMEM;
1941   }
1942 
1943   /* Initialize the local lockdata */
1944   memset(&pFile->local, 0, sizeof(pFile->local));
1945 
1946   /* Replace the backslashes from the filename and lowercase it
1947   ** to derive a mutex name. */
1948   zTok = osCharLowerW(zName);
1949   for (;*zTok;zTok++){
1950     if (*zTok == '\\') *zTok = '_';
1951   }
1952 
1953   /* Create/open the named mutex */
1954   pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
1955   if (!pFile->hMutex){
1956     pFile->lastErrno = osGetLastError();
1957     sqlite3_free(zName);
1958     return winLogError(SQLITE_IOERR, pFile->lastErrno,
1959                        "winceCreateLock1", zFilename);
1960   }
1961 
1962   /* Acquire the mutex before continuing */
1963   winceMutexAcquire(pFile->hMutex);
1964 
1965   /* Since the names of named mutexes, semaphores, file mappings etc are
1966   ** case-sensitive, take advantage of that by uppercasing the mutex name
1967   ** and using that as the shared filemapping name.
1968   */
1969   osCharUpperW(zName);
1970   pFile->hShared = osCreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
1971                                         PAGE_READWRITE, 0, sizeof(winceLock),
1972                                         zName);
1973 
1974   /* Set a flag that indicates we're the first to create the memory so it
1975   ** must be zero-initialized */
1976   lastErrno = osGetLastError();
1977   if (lastErrno == ERROR_ALREADY_EXISTS){
1978     bInit = FALSE;
1979   }
1980 
1981   sqlite3_free(zName);
1982 
1983   /* If we succeeded in making the shared memory handle, map it. */
1984   if( pFile->hShared ){
1985     pFile->shared = (winceLock*)osMapViewOfFile(pFile->hShared,
1986              FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
1987     /* If mapping failed, close the shared memory handle and erase it */
1988     if( !pFile->shared ){
1989       pFile->lastErrno = osGetLastError();
1990       winLogError(SQLITE_IOERR, pFile->lastErrno,
1991                   "winceCreateLock2", zFilename);
1992       bLogged = TRUE;
1993       osCloseHandle(pFile->hShared);
1994       pFile->hShared = NULL;
1995     }
1996   }
1997 
1998   /* If shared memory could not be created, then close the mutex and fail */
1999   if( pFile->hShared==NULL ){
2000     if( !bLogged ){
2001       pFile->lastErrno = lastErrno;
2002       winLogError(SQLITE_IOERR, pFile->lastErrno,
2003                   "winceCreateLock3", zFilename);
2004       bLogged = TRUE;
2005     }
2006     winceMutexRelease(pFile->hMutex);
2007     osCloseHandle(pFile->hMutex);
2008     pFile->hMutex = NULL;
2009     return SQLITE_IOERR;
2010   }
2011 
2012   /* Initialize the shared memory if we're supposed to */
2013   if( bInit ){
2014     memset(pFile->shared, 0, sizeof(winceLock));
2015   }
2016 
2017   winceMutexRelease(pFile->hMutex);
2018   return SQLITE_OK;
2019 }
2020 
2021 /*
2022 ** Destroy the part of winFile that deals with wince locks
2023 */
2024 static void winceDestroyLock(winFile *pFile){
2025   if (pFile->hMutex){
2026     /* Acquire the mutex */
2027     winceMutexAcquire(pFile->hMutex);
2028 
2029     /* The following blocks should probably assert in debug mode, but they
2030        are to cleanup in case any locks remained open */
2031     if (pFile->local.nReaders){
2032       pFile->shared->nReaders --;
2033     }
2034     if (pFile->local.bReserved){
2035       pFile->shared->bReserved = FALSE;
2036     }
2037     if (pFile->local.bPending){
2038       pFile->shared->bPending = FALSE;
2039     }
2040     if (pFile->local.bExclusive){
2041       pFile->shared->bExclusive = FALSE;
2042     }
2043 
2044     /* De-reference and close our copy of the shared memory handle */
2045     osUnmapViewOfFile(pFile->shared);
2046     osCloseHandle(pFile->hShared);
2047 
2048     /* Done with the mutex */
2049     winceMutexRelease(pFile->hMutex);
2050     osCloseHandle(pFile->hMutex);
2051     pFile->hMutex = NULL;
2052   }
2053 }
2054 
2055 /*
2056 ** An implementation of the LockFile() API of Windows for CE
2057 */
2058 static BOOL winceLockFile(
2059   LPHANDLE phFile,
2060   DWORD dwFileOffsetLow,
2061   DWORD dwFileOffsetHigh,
2062   DWORD nNumberOfBytesToLockLow,
2063   DWORD nNumberOfBytesToLockHigh
2064 ){
2065   winFile *pFile = HANDLE_TO_WINFILE(phFile);
2066   BOOL bReturn = FALSE;
2067 
2068   UNUSED_PARAMETER(dwFileOffsetHigh);
2069   UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
2070 
2071   if (!pFile->hMutex) return TRUE;
2072   winceMutexAcquire(pFile->hMutex);
2073 
2074   /* Wanting an exclusive lock? */
2075   if (dwFileOffsetLow == (DWORD)SHARED_FIRST
2076        && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
2077     if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
2078        pFile->shared->bExclusive = TRUE;
2079        pFile->local.bExclusive = TRUE;
2080        bReturn = TRUE;
2081     }
2082   }
2083 
2084   /* Want a read-only lock? */
2085   else if (dwFileOffsetLow == (DWORD)SHARED_FIRST &&
2086            nNumberOfBytesToLockLow == 1){
2087     if (pFile->shared->bExclusive == 0){
2088       pFile->local.nReaders ++;
2089       if (pFile->local.nReaders == 1){
2090         pFile->shared->nReaders ++;
2091       }
2092       bReturn = TRUE;
2093     }
2094   }
2095 
2096   /* Want a pending lock? */
2097   else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
2098            && nNumberOfBytesToLockLow == 1){
2099     /* If no pending lock has been acquired, then acquire it */
2100     if (pFile->shared->bPending == 0) {
2101       pFile->shared->bPending = TRUE;
2102       pFile->local.bPending = TRUE;
2103       bReturn = TRUE;
2104     }
2105   }
2106 
2107   /* Want a reserved lock? */
2108   else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
2109            && nNumberOfBytesToLockLow == 1){
2110     if (pFile->shared->bReserved == 0) {
2111       pFile->shared->bReserved = TRUE;
2112       pFile->local.bReserved = TRUE;
2113       bReturn = TRUE;
2114     }
2115   }
2116 
2117   winceMutexRelease(pFile->hMutex);
2118   return bReturn;
2119 }
2120 
2121 /*
2122 ** An implementation of the UnlockFile API of Windows for CE
2123 */
2124 static BOOL winceUnlockFile(
2125   LPHANDLE phFile,
2126   DWORD dwFileOffsetLow,
2127   DWORD dwFileOffsetHigh,
2128   DWORD nNumberOfBytesToUnlockLow,
2129   DWORD nNumberOfBytesToUnlockHigh
2130 ){
2131   winFile *pFile = HANDLE_TO_WINFILE(phFile);
2132   BOOL bReturn = FALSE;
2133 
2134   UNUSED_PARAMETER(dwFileOffsetHigh);
2135   UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);
2136 
2137   if (!pFile->hMutex) return TRUE;
2138   winceMutexAcquire(pFile->hMutex);
2139 
2140   /* Releasing a reader lock or an exclusive lock */
2141   if (dwFileOffsetLow == (DWORD)SHARED_FIRST){
2142     /* Did we have an exclusive lock? */
2143     if (pFile->local.bExclusive){
2144       assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE);
2145       pFile->local.bExclusive = FALSE;
2146       pFile->shared->bExclusive = FALSE;
2147       bReturn = TRUE;
2148     }
2149 
2150     /* Did we just have a reader lock? */
2151     else if (pFile->local.nReaders){
2152       assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE
2153              || nNumberOfBytesToUnlockLow == 1);
2154       pFile->local.nReaders --;
2155       if (pFile->local.nReaders == 0)
2156       {
2157         pFile->shared->nReaders --;
2158       }
2159       bReturn = TRUE;
2160     }
2161   }
2162 
2163   /* Releasing a pending lock */
2164   else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
2165            && nNumberOfBytesToUnlockLow == 1){
2166     if (pFile->local.bPending){
2167       pFile->local.bPending = FALSE;
2168       pFile->shared->bPending = FALSE;
2169       bReturn = TRUE;
2170     }
2171   }
2172   /* Releasing a reserved lock */
2173   else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
2174            && nNumberOfBytesToUnlockLow == 1){
2175     if (pFile->local.bReserved) {
2176       pFile->local.bReserved = FALSE;
2177       pFile->shared->bReserved = FALSE;
2178       bReturn = TRUE;
2179     }
2180   }
2181 
2182   winceMutexRelease(pFile->hMutex);
2183   return bReturn;
2184 }
2185 /*
2186 ** End of the special code for wince
2187 *****************************************************************************/
2188 #endif /* SQLITE_OS_WINCE */
2189 
2190 /*
2191 ** Lock a file region.
2192 */
2193 static BOOL winLockFile(
2194   LPHANDLE phFile,
2195   DWORD flags,
2196   DWORD offsetLow,
2197   DWORD offsetHigh,
2198   DWORD numBytesLow,
2199   DWORD numBytesHigh
2200 ){
2201 #if SQLITE_OS_WINCE
2202   /*
2203   ** NOTE: Windows CE is handled differently here due its lack of the Win32
2204   **       API LockFile.
2205   */
2206   return winceLockFile(phFile, offsetLow, offsetHigh,
2207                        numBytesLow, numBytesHigh);
2208 #else
2209   if( osIsNT() ){
2210     OVERLAPPED ovlp;
2211     memset(&ovlp, 0, sizeof(OVERLAPPED));
2212     ovlp.Offset = offsetLow;
2213     ovlp.OffsetHigh = offsetHigh;
2214     return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
2215   }else{
2216     return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
2217                       numBytesHigh);
2218   }
2219 #endif
2220 }
2221 
2222 /*
2223 ** Unlock a file region.
2224  */
2225 static BOOL winUnlockFile(
2226   LPHANDLE phFile,
2227   DWORD offsetLow,
2228   DWORD offsetHigh,
2229   DWORD numBytesLow,
2230   DWORD numBytesHigh
2231 ){
2232 #if SQLITE_OS_WINCE
2233   /*
2234   ** NOTE: Windows CE is handled differently here due its lack of the Win32
2235   **       API UnlockFile.
2236   */
2237   return winceUnlockFile(phFile, offsetLow, offsetHigh,
2238                          numBytesLow, numBytesHigh);
2239 #else
2240   if( osIsNT() ){
2241     OVERLAPPED ovlp;
2242     memset(&ovlp, 0, sizeof(OVERLAPPED));
2243     ovlp.Offset = offsetLow;
2244     ovlp.OffsetHigh = offsetHigh;
2245     return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
2246   }else{
2247     return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
2248                         numBytesHigh);
2249   }
2250 #endif
2251 }
2252 
2253 /*****************************************************************************
2254 ** The next group of routines implement the I/O methods specified
2255 ** by the sqlite3_io_methods object.
2256 ******************************************************************************/
2257 
2258 /*
2259 ** Some Microsoft compilers lack this definition.
2260 */
2261 #ifndef INVALID_SET_FILE_POINTER
2262 # define INVALID_SET_FILE_POINTER ((DWORD)-1)
2263 #endif
2264 
2265 /*
2266 ** Move the current position of the file handle passed as the first
2267 ** argument to offset iOffset within the file. If successful, return 0.
2268 ** Otherwise, set pFile->lastErrno and return non-zero.
2269 */
2270 static int winSeekFile(winFile *pFile, sqlite3_int64 iOffset){
2271 #if !SQLITE_OS_WINRT
2272   LONG upperBits;                 /* Most sig. 32 bits of new offset */
2273   LONG lowerBits;                 /* Least sig. 32 bits of new offset */
2274   DWORD dwRet;                    /* Value returned by SetFilePointer() */
2275   DWORD lastErrno;                /* Value returned by GetLastError() */
2276 
2277   OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
2278 
2279   upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
2280   lowerBits = (LONG)(iOffset & 0xffffffff);
2281 
2282   /* API oddity: If successful, SetFilePointer() returns a dword
2283   ** containing the lower 32-bits of the new file-offset. Or, if it fails,
2284   ** it returns INVALID_SET_FILE_POINTER. However according to MSDN,
2285   ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine
2286   ** whether an error has actually occurred, it is also necessary to call
2287   ** GetLastError().
2288   */
2289   dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
2290 
2291   if( (dwRet==INVALID_SET_FILE_POINTER
2292       && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
2293     pFile->lastErrno = lastErrno;
2294     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
2295                 "winSeekFile", pFile->zPath);
2296     OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
2297     return 1;
2298   }
2299 
2300   OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
2301   return 0;
2302 #else
2303   /*
2304   ** Same as above, except that this implementation works for WinRT.
2305   */
2306 
2307   LARGE_INTEGER x;                /* The new offset */
2308   BOOL bRet;                      /* Value returned by SetFilePointerEx() */
2309 
2310   x.QuadPart = iOffset;
2311   bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);
2312 
2313   if(!bRet){
2314     pFile->lastErrno = osGetLastError();
2315     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
2316                 "winSeekFile", pFile->zPath);
2317     OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
2318     return 1;
2319   }
2320 
2321   OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
2322   return 0;
2323 #endif
2324 }
2325 
2326 #if SQLITE_MAX_MMAP_SIZE>0
2327 /* Forward references to VFS helper methods used for memory mapped files */
2328 static int winMapfile(winFile*, sqlite3_int64);
2329 static int winUnmapfile(winFile*);
2330 #endif
2331 
2332 /*
2333 ** Close a file.
2334 **
2335 ** It is reported that an attempt to close a handle might sometimes
2336 ** fail.  This is a very unreasonable result, but Windows is notorious
2337 ** for being unreasonable so I do not doubt that it might happen.  If
2338 ** the close fails, we pause for 100 milliseconds and try again.  As
2339 ** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
2340 ** giving up and returning an error.
2341 */
2342 #define MX_CLOSE_ATTEMPT 3
2343 static int winClose(sqlite3_file *id){
2344   int rc, cnt = 0;
2345   winFile *pFile = (winFile*)id;
2346 
2347   assert( id!=0 );
2348 #ifndef SQLITE_OMIT_WAL
2349   assert( pFile->pShm==0 );
2350 #endif
2351   assert( pFile->h!=NULL && pFile->h!=INVALID_HANDLE_VALUE );
2352   OSTRACE(("CLOSE file=%p\n", pFile->h));
2353 
2354 #if SQLITE_MAX_MMAP_SIZE>0
2355   winUnmapfile(pFile);
2356 #endif
2357 
2358   do{
2359     rc = osCloseHandle(pFile->h);
2360     /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
2361   }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (sqlite3_win32_sleep(100), 1) );
2362 #if SQLITE_OS_WINCE
2363 #define WINCE_DELETION_ATTEMPTS 3
2364   winceDestroyLock(pFile);
2365   if( pFile->zDeleteOnClose ){
2366     int cnt = 0;
2367     while(
2368            osDeleteFileW(pFile->zDeleteOnClose)==0
2369         && osGetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff
2370         && cnt++ < WINCE_DELETION_ATTEMPTS
2371     ){
2372        sqlite3_win32_sleep(100);  /* Wait a little before trying again */
2373     }
2374     sqlite3_free(pFile->zDeleteOnClose);
2375   }
2376 #endif
2377   if( rc ){
2378     pFile->h = NULL;
2379   }
2380   OpenCounter(-1);
2381   OSTRACE(("CLOSE file=%p, rc=%s\n", pFile->h, rc ? "ok" : "failed"));
2382   return rc ? SQLITE_OK
2383             : winLogError(SQLITE_IOERR_CLOSE, osGetLastError(),
2384                           "winClose", pFile->zPath);
2385 }
2386 
2387 /*
2388 ** Read data from a file into a buffer.  Return SQLITE_OK if all
2389 ** bytes were read successfully and SQLITE_IOERR if anything goes
2390 ** wrong.
2391 */
2392 static int winRead(
2393   sqlite3_file *id,          /* File to read from */
2394   void *pBuf,                /* Write content into this buffer */
2395   int amt,                   /* Number of bytes to read */
2396   sqlite3_int64 offset       /* Begin reading at this offset */
2397 ){
2398 #if !SQLITE_OS_WINCE
2399   OVERLAPPED overlapped;          /* The offset for ReadFile. */
2400 #endif
2401   winFile *pFile = (winFile*)id;  /* file handle */
2402   DWORD nRead;                    /* Number of bytes actually read from file */
2403   int nRetry = 0;                 /* Number of retrys */
2404 
2405   assert( id!=0 );
2406   assert( amt>0 );
2407   assert( offset>=0 );
2408   SimulateIOError(return SQLITE_IOERR_READ);
2409   OSTRACE(("READ file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
2410            pFile->h, pBuf, amt, offset, pFile->locktype));
2411 
2412 #if SQLITE_MAX_MMAP_SIZE>0
2413   /* Deal with as much of this read request as possible by transfering
2414   ** data from the memory mapping using memcpy().  */
2415   if( offset<pFile->mmapSize ){
2416     if( offset+amt <= pFile->mmapSize ){
2417       memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
2418       OSTRACE(("READ-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
2419       return SQLITE_OK;
2420     }else{
2421       int nCopy = (int)(pFile->mmapSize - offset);
2422       memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
2423       pBuf = &((u8 *)pBuf)[nCopy];
2424       amt -= nCopy;
2425       offset += nCopy;
2426     }
2427   }
2428 #endif
2429 
2430 #if SQLITE_OS_WINCE
2431   if( winSeekFile(pFile, offset) ){
2432     OSTRACE(("READ file=%p, rc=SQLITE_FULL\n", pFile->h));
2433     return SQLITE_FULL;
2434   }
2435   while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
2436 #else
2437   memset(&overlapped, 0, sizeof(OVERLAPPED));
2438   overlapped.Offset = (LONG)(offset & 0xffffffff);
2439   overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2440   while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
2441          osGetLastError()!=ERROR_HANDLE_EOF ){
2442 #endif
2443     DWORD lastErrno;
2444     if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
2445     pFile->lastErrno = lastErrno;
2446     OSTRACE(("READ file=%p, rc=SQLITE_IOERR_READ\n", pFile->h));
2447     return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
2448                        "winRead", pFile->zPath);
2449   }
2450   winLogIoerr(nRetry);
2451   if( nRead<(DWORD)amt ){
2452     /* Unread parts of the buffer must be zero-filled */
2453     memset(&((char*)pBuf)[nRead], 0, amt-nRead);
2454     OSTRACE(("READ file=%p, rc=SQLITE_IOERR_SHORT_READ\n", pFile->h));
2455     return SQLITE_IOERR_SHORT_READ;
2456   }
2457 
2458   OSTRACE(("READ file=%p, rc=SQLITE_OK\n", pFile->h));
2459   return SQLITE_OK;
2460 }
2461 
2462 /*
2463 ** Write data from a buffer into a file.  Return SQLITE_OK on success
2464 ** or some other error code on failure.
2465 */
2466 static int winWrite(
2467   sqlite3_file *id,               /* File to write into */
2468   const void *pBuf,               /* The bytes to be written */
2469   int amt,                        /* Number of bytes to write */
2470   sqlite3_int64 offset            /* Offset into the file to begin writing at */
2471 ){
2472   int rc = 0;                     /* True if error has occurred, else false */
2473   winFile *pFile = (winFile*)id;  /* File handle */
2474   int nRetry = 0;                 /* Number of retries */
2475 
2476   assert( amt>0 );
2477   assert( pFile );
2478   SimulateIOError(return SQLITE_IOERR_WRITE);
2479   SimulateDiskfullError(return SQLITE_FULL);
2480 
2481   OSTRACE(("WRITE file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
2482            pFile->h, pBuf, amt, offset, pFile->locktype));
2483 
2484 #if SQLITE_MAX_MMAP_SIZE>0
2485   /* Deal with as much of this write request as possible by transfering
2486   ** data from the memory mapping using memcpy().  */
2487   if( offset<pFile->mmapSize ){
2488     if( offset+amt <= pFile->mmapSize ){
2489       memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
2490       OSTRACE(("WRITE-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
2491       return SQLITE_OK;
2492     }else{
2493       int nCopy = (int)(pFile->mmapSize - offset);
2494       memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
2495       pBuf = &((u8 *)pBuf)[nCopy];
2496       amt -= nCopy;
2497       offset += nCopy;
2498     }
2499   }
2500 #endif
2501 
2502 #if SQLITE_OS_WINCE
2503   rc = winSeekFile(pFile, offset);
2504   if( rc==0 ){
2505 #else
2506   {
2507 #endif
2508 #if !SQLITE_OS_WINCE
2509     OVERLAPPED overlapped;        /* The offset for WriteFile. */
2510 #endif
2511     u8 *aRem = (u8 *)pBuf;        /* Data yet to be written */
2512     int nRem = amt;               /* Number of bytes yet to be written */
2513     DWORD nWrite;                 /* Bytes written by each WriteFile() call */
2514     DWORD lastErrno = NO_ERROR;   /* Value returned by GetLastError() */
2515 
2516 #if !SQLITE_OS_WINCE
2517     memset(&overlapped, 0, sizeof(OVERLAPPED));
2518     overlapped.Offset = (LONG)(offset & 0xffffffff);
2519     overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2520 #endif
2521 
2522     while( nRem>0 ){
2523 #if SQLITE_OS_WINCE
2524       if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
2525 #else
2526       if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
2527 #endif
2528         if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
2529         break;
2530       }
2531       assert( nWrite==0 || nWrite<=(DWORD)nRem );
2532       if( nWrite==0 || nWrite>(DWORD)nRem ){
2533         lastErrno = osGetLastError();
2534         break;
2535       }
2536 #if !SQLITE_OS_WINCE
2537       offset += nWrite;
2538       overlapped.Offset = (LONG)(offset & 0xffffffff);
2539       overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
2540 #endif
2541       aRem += nWrite;
2542       nRem -= nWrite;
2543     }
2544     if( nRem>0 ){
2545       pFile->lastErrno = lastErrno;
2546       rc = 1;
2547     }
2548   }
2549 
2550   if( rc ){
2551     if(   ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
2552        || ( pFile->lastErrno==ERROR_DISK_FULL )){
2553       OSTRACE(("WRITE file=%p, rc=SQLITE_FULL\n", pFile->h));
2554       return winLogError(SQLITE_FULL, pFile->lastErrno,
2555                          "winWrite1", pFile->zPath);
2556     }
2557     OSTRACE(("WRITE file=%p, rc=SQLITE_IOERR_WRITE\n", pFile->h));
2558     return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
2559                        "winWrite2", pFile->zPath);
2560   }else{
2561     winLogIoerr(nRetry);
2562   }
2563   OSTRACE(("WRITE file=%p, rc=SQLITE_OK\n", pFile->h));
2564   return SQLITE_OK;
2565 }
2566 
2567 /*
2568 ** Truncate an open file to a specified size
2569 */
2570 static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
2571   winFile *pFile = (winFile*)id;  /* File handle object */
2572   int rc = SQLITE_OK;             /* Return code for this function */
2573   DWORD lastErrno;
2574 
2575   assert( pFile );
2576   SimulateIOError(return SQLITE_IOERR_TRUNCATE);
2577   OSTRACE(("TRUNCATE file=%p, size=%lld, lock=%d\n",
2578            pFile->h, nByte, pFile->locktype));
2579 
2580   /* If the user has configured a chunk-size for this file, truncate the
2581   ** file so that it consists of an integer number of chunks (i.e. the
2582   ** actual file size after the operation may be larger than the requested
2583   ** size).
2584   */
2585   if( pFile->szChunk>0 ){
2586     nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
2587   }
2588 
2589   /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
2590   if( winSeekFile(pFile, nByte) ){
2591     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
2592                      "winTruncate1", pFile->zPath);
2593   }else if( 0==osSetEndOfFile(pFile->h) &&
2594             ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
2595     pFile->lastErrno = lastErrno;
2596     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
2597                      "winTruncate2", pFile->zPath);
2598   }
2599 
2600 #if SQLITE_MAX_MMAP_SIZE>0
2601   /* If the file was truncated to a size smaller than the currently
2602   ** mapped region, reduce the effective mapping size as well. SQLite will
2603   ** use read() and write() to access data beyond this point from now on.
2604   */
2605   if( pFile->pMapRegion && nByte<pFile->mmapSize ){
2606     pFile->mmapSize = nByte;
2607   }
2608 #endif
2609 
2610   OSTRACE(("TRUNCATE file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
2611   return rc;
2612 }
2613 
2614 #ifdef SQLITE_TEST
2615 /*
2616 ** Count the number of fullsyncs and normal syncs.  This is used to test
2617 ** that syncs and fullsyncs are occuring at the right times.
2618 */
2619 int sqlite3_sync_count = 0;
2620 int sqlite3_fullsync_count = 0;
2621 #endif
2622 
2623 /*
2624 ** Make sure all writes to a particular file are committed to disk.
2625 */
2626 static int winSync(sqlite3_file *id, int flags){
2627 #ifndef SQLITE_NO_SYNC
2628   /*
2629   ** Used only when SQLITE_NO_SYNC is not defined.
2630    */
2631   BOOL rc;
2632 #endif
2633 #if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || \
2634     (defined(SQLITE_TEST) && defined(SQLITE_DEBUG))
2635   /*
2636   ** Used when SQLITE_NO_SYNC is not defined and by the assert() and/or
2637   ** OSTRACE() macros.
2638    */
2639   winFile *pFile = (winFile*)id;
2640 #else
2641   UNUSED_PARAMETER(id);
2642 #endif
2643 
2644   assert( pFile );
2645   /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
2646   assert((flags&0x0F)==SQLITE_SYNC_NORMAL
2647       || (flags&0x0F)==SQLITE_SYNC_FULL
2648   );
2649 
2650   /* Unix cannot, but some systems may return SQLITE_FULL from here. This
2651   ** line is to test that doing so does not cause any problems.
2652   */
2653   SimulateDiskfullError( return SQLITE_FULL );
2654 
2655   OSTRACE(("SYNC file=%p, flags=%x, lock=%d\n",
2656            pFile->h, flags, pFile->locktype));
2657 
2658 #ifndef SQLITE_TEST
2659   UNUSED_PARAMETER(flags);
2660 #else
2661   if( (flags&0x0F)==SQLITE_SYNC_FULL ){
2662     sqlite3_fullsync_count++;
2663   }
2664   sqlite3_sync_count++;
2665 #endif
2666 
2667   /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
2668   ** no-op
2669   */
2670 #ifdef SQLITE_NO_SYNC
2671   OSTRACE(("SYNC-NOP file=%p, rc=SQLITE_OK\n", pFile->h));
2672   return SQLITE_OK;
2673 #else
2674   rc = osFlushFileBuffers(pFile->h);
2675   SimulateIOError( rc=FALSE );
2676   if( rc ){
2677     OSTRACE(("SYNC file=%p, rc=SQLITE_OK\n", pFile->h));
2678     return SQLITE_OK;
2679   }else{
2680     pFile->lastErrno = osGetLastError();
2681     OSTRACE(("SYNC file=%p, rc=SQLITE_IOERR_FSYNC\n", pFile->h));
2682     return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
2683                        "winSync", pFile->zPath);
2684   }
2685 #endif
2686 }
2687 
2688 /*
2689 ** Determine the current size of a file in bytes
2690 */
2691 static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
2692   winFile *pFile = (winFile*)id;
2693   int rc = SQLITE_OK;
2694 
2695   assert( id!=0 );
2696   assert( pSize!=0 );
2697   SimulateIOError(return SQLITE_IOERR_FSTAT);
2698   OSTRACE(("SIZE file=%p, pSize=%p\n", pFile->h, pSize));
2699 
2700 #if SQLITE_OS_WINRT
2701   {
2702     FILE_STANDARD_INFO info;
2703     if( osGetFileInformationByHandleEx(pFile->h, FileStandardInfo,
2704                                      &info, sizeof(info)) ){
2705       *pSize = info.EndOfFile.QuadPart;
2706     }else{
2707       pFile->lastErrno = osGetLastError();
2708       rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
2709                        "winFileSize", pFile->zPath);
2710     }
2711   }
2712 #else
2713   {
2714     DWORD upperBits;
2715     DWORD lowerBits;
2716     DWORD lastErrno;
2717 
2718     lowerBits = osGetFileSize(pFile->h, &upperBits);
2719     *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
2720     if(   (lowerBits == INVALID_FILE_SIZE)
2721        && ((lastErrno = osGetLastError())!=NO_ERROR) ){
2722       pFile->lastErrno = lastErrno;
2723       rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
2724                        "winFileSize", pFile->zPath);
2725     }
2726   }
2727 #endif
2728   OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
2729            pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
2730   return rc;
2731 }
2732 
2733 /*
2734 ** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
2735 */
2736 #ifndef LOCKFILE_FAIL_IMMEDIATELY
2737 # define LOCKFILE_FAIL_IMMEDIATELY 1
2738 #endif
2739 
2740 #ifndef LOCKFILE_EXCLUSIVE_LOCK
2741 # define LOCKFILE_EXCLUSIVE_LOCK 2
2742 #endif
2743 
2744 /*
2745 ** Historically, SQLite has used both the LockFile and LockFileEx functions.
2746 ** When the LockFile function was used, it was always expected to fail
2747 ** immediately if the lock could not be obtained.  Also, it always expected to
2748 ** obtain an exclusive lock.  These flags are used with the LockFileEx function
2749 ** and reflect those expectations; therefore, they should not be changed.
2750 */
2751 #ifndef SQLITE_LOCKFILE_FLAGS
2752 # define SQLITE_LOCKFILE_FLAGS   (LOCKFILE_FAIL_IMMEDIATELY | \
2753                                   LOCKFILE_EXCLUSIVE_LOCK)
2754 #endif
2755 
2756 /*
2757 ** Currently, SQLite never calls the LockFileEx function without wanting the
2758 ** call to fail immediately if the lock cannot be obtained.
2759 */
2760 #ifndef SQLITE_LOCKFILEEX_FLAGS
2761 # define SQLITE_LOCKFILEEX_FLAGS (LOCKFILE_FAIL_IMMEDIATELY)
2762 #endif
2763 
2764 /*
2765 ** Acquire a reader lock.
2766 ** Different API routines are called depending on whether or not this
2767 ** is Win9x or WinNT.
2768 */
2769 static int winGetReadLock(winFile *pFile){
2770   int res;
2771   OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
2772   if( osIsNT() ){
2773 #if SQLITE_OS_WINCE
2774     /*
2775     ** NOTE: Windows CE is handled differently here due its lack of the Win32
2776     **       API LockFileEx.
2777     */
2778     res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
2779 #else
2780     res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS, SHARED_FIRST, 0,
2781                       SHARED_SIZE, 0);
2782 #endif
2783   }
2784 #ifdef SQLITE_WIN32_HAS_ANSI
2785   else{
2786     int lk;
2787     sqlite3_randomness(sizeof(lk), &lk);
2788     pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
2789     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
2790                       SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
2791   }
2792 #endif
2793   if( res == 0 ){
2794     pFile->lastErrno = osGetLastError();
2795     /* No need to log a failure to lock */
2796   }
2797   OSTRACE(("READ-LOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
2798   return res;
2799 }
2800 
2801 /*
2802 ** Undo a readlock
2803 */
2804 static int winUnlockReadLock(winFile *pFile){
2805   int res;
2806   DWORD lastErrno;
2807   OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
2808   if( osIsNT() ){
2809     res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
2810   }
2811 #ifdef SQLITE_WIN32_HAS_ANSI
2812   else{
2813     res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
2814   }
2815 #endif
2816   if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
2817     pFile->lastErrno = lastErrno;
2818     winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
2819                 "winUnlockReadLock", pFile->zPath);
2820   }
2821   OSTRACE(("READ-UNLOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
2822   return res;
2823 }
2824 
2825 /*
2826 ** Lock the file with the lock specified by parameter locktype - one
2827 ** of the following:
2828 **
2829 **     (1) SHARED_LOCK
2830 **     (2) RESERVED_LOCK
2831 **     (3) PENDING_LOCK
2832 **     (4) EXCLUSIVE_LOCK
2833 **
2834 ** Sometimes when requesting one lock state, additional lock states
2835 ** are inserted in between.  The locking might fail on one of the later
2836 ** transitions leaving the lock state different from what it started but
2837 ** still short of its goal.  The following chart shows the allowed
2838 ** transitions and the inserted intermediate states:
2839 **
2840 **    UNLOCKED -> SHARED
2841 **    SHARED -> RESERVED
2842 **    SHARED -> (PENDING) -> EXCLUSIVE
2843 **    RESERVED -> (PENDING) -> EXCLUSIVE
2844 **    PENDING -> EXCLUSIVE
2845 **
2846 ** This routine will only increase a lock.  The winUnlock() routine
2847 ** erases all locks at once and returns us immediately to locking level 0.
2848 ** It is not possible to lower the locking level one step at a time.  You
2849 ** must go straight to locking level 0.
2850 */
2851 static int winLock(sqlite3_file *id, int locktype){
2852   int rc = SQLITE_OK;    /* Return code from subroutines */
2853   int res = 1;           /* Result of a Windows lock call */
2854   int newLocktype;       /* Set pFile->locktype to this value before exiting */
2855   int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
2856   winFile *pFile = (winFile*)id;
2857   DWORD lastErrno = NO_ERROR;
2858 
2859   assert( id!=0 );
2860   OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
2861            pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
2862 
2863   /* If there is already a lock of this type or more restrictive on the
2864   ** OsFile, do nothing. Don't use the end_lock: exit path, as
2865   ** sqlite3OsEnterMutex() hasn't been called yet.
2866   */
2867   if( pFile->locktype>=locktype ){
2868     OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
2869     return SQLITE_OK;
2870   }
2871 
2872   /* Make sure the locking sequence is correct
2873   */
2874   assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
2875   assert( locktype!=PENDING_LOCK );
2876   assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
2877 
2878   /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
2879   ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
2880   ** the PENDING_LOCK byte is temporary.
2881   */
2882   newLocktype = pFile->locktype;
2883   if(   (pFile->locktype==NO_LOCK)
2884      || (   (locktype==EXCLUSIVE_LOCK)
2885          && (pFile->locktype==RESERVED_LOCK))
2886   ){
2887     int cnt = 3;
2888     while( cnt-->0 && (res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
2889                                          PENDING_BYTE, 0, 1, 0))==0 ){
2890       /* Try 3 times to get the pending lock.  This is needed to work
2891       ** around problems caused by indexing and/or anti-virus software on
2892       ** Windows systems.
2893       ** If you are using this code as a model for alternative VFSes, do not
2894       ** copy this retry logic.  It is a hack intended for Windows only.
2895       */
2896       OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, rc=%s\n",
2897                pFile->h, cnt, sqlite3ErrName(res)));
2898       if( cnt ) sqlite3_win32_sleep(1);
2899     }
2900     gotPendingLock = res;
2901     if( !res ){
2902       lastErrno = osGetLastError();
2903     }
2904   }
2905 
2906   /* Acquire a shared lock
2907   */
2908   if( locktype==SHARED_LOCK && res ){
2909     assert( pFile->locktype==NO_LOCK );
2910     res = winGetReadLock(pFile);
2911     if( res ){
2912       newLocktype = SHARED_LOCK;
2913     }else{
2914       lastErrno = osGetLastError();
2915     }
2916   }
2917 
2918   /* Acquire a RESERVED lock
2919   */
2920   if( locktype==RESERVED_LOCK && res ){
2921     assert( pFile->locktype==SHARED_LOCK );
2922     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, RESERVED_BYTE, 0, 1, 0);
2923     if( res ){
2924       newLocktype = RESERVED_LOCK;
2925     }else{
2926       lastErrno = osGetLastError();
2927     }
2928   }
2929 
2930   /* Acquire a PENDING lock
2931   */
2932   if( locktype==EXCLUSIVE_LOCK && res ){
2933     newLocktype = PENDING_LOCK;
2934     gotPendingLock = 0;
2935   }
2936 
2937   /* Acquire an EXCLUSIVE lock
2938   */
2939   if( locktype==EXCLUSIVE_LOCK && res ){
2940     assert( pFile->locktype>=SHARED_LOCK );
2941     res = winUnlockReadLock(pFile);
2942     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
2943                       SHARED_SIZE, 0);
2944     if( res ){
2945       newLocktype = EXCLUSIVE_LOCK;
2946     }else{
2947       lastErrno = osGetLastError();
2948       winGetReadLock(pFile);
2949     }
2950   }
2951 
2952   /* If we are holding a PENDING lock that ought to be released, then
2953   ** release it now.
2954   */
2955   if( gotPendingLock && locktype==SHARED_LOCK ){
2956     winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
2957   }
2958 
2959   /* Update the state of the lock has held in the file descriptor then
2960   ** return the appropriate result code.
2961   */
2962   if( res ){
2963     rc = SQLITE_OK;
2964   }else{
2965     pFile->lastErrno = lastErrno;
2966     rc = SQLITE_BUSY;
2967     OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
2968              pFile->h, locktype, newLocktype));
2969   }
2970   pFile->locktype = (u8)newLocktype;
2971   OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
2972            pFile->h, pFile->locktype, sqlite3ErrName(rc)));
2973   return rc;
2974 }
2975 
2976 /*
2977 ** This routine checks if there is a RESERVED lock held on the specified
2978 ** file by this or any other process. If such a lock is held, return
2979 ** non-zero, otherwise zero.
2980 */
2981 static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
2982   int rc;
2983   winFile *pFile = (winFile*)id;
2984 
2985   SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
2986   OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));
2987 
2988   assert( id!=0 );
2989   if( pFile->locktype>=RESERVED_LOCK ){
2990     rc = 1;
2991     OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (local)\n", pFile->h, rc));
2992   }else{
2993     rc = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
2994     if( rc ){
2995       winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
2996     }
2997     rc = !rc;
2998     OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (remote)\n", pFile->h, rc));
2999   }
3000   *pResOut = rc;
3001   OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
3002            pFile->h, pResOut, *pResOut));
3003   return SQLITE_OK;
3004 }
3005 
3006 /*
3007 ** Lower the locking level on file descriptor id to locktype.  locktype
3008 ** must be either NO_LOCK or SHARED_LOCK.
3009 **
3010 ** If the locking level of the file descriptor is already at or below
3011 ** the requested locking level, this routine is a no-op.
3012 **
3013 ** It is not possible for this routine to fail if the second argument
3014 ** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
3015 ** might return SQLITE_IOERR;
3016 */
3017 static int winUnlock(sqlite3_file *id, int locktype){
3018   int type;
3019   winFile *pFile = (winFile*)id;
3020   int rc = SQLITE_OK;
3021   assert( pFile!=0 );
3022   assert( locktype<=SHARED_LOCK );
3023   OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
3024            pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
3025   type = pFile->locktype;
3026   if( type>=EXCLUSIVE_LOCK ){
3027     winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
3028     if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
3029       /* This should never happen.  We should always be able to
3030       ** reacquire the read lock */
3031       rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
3032                        "winUnlock", pFile->zPath);
3033     }
3034   }
3035   if( type>=RESERVED_LOCK ){
3036     winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
3037   }
3038   if( locktype==NO_LOCK && type>=SHARED_LOCK ){
3039     winUnlockReadLock(pFile);
3040   }
3041   if( type>=PENDING_LOCK ){
3042     winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
3043   }
3044   pFile->locktype = (u8)locktype;
3045   OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
3046            pFile->h, pFile->locktype, sqlite3ErrName(rc)));
3047   return rc;
3048 }
3049 
3050 /*
3051 ** If *pArg is inititially negative then this is a query.  Set *pArg to
3052 ** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
3053 **
3054 ** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
3055 */
3056 static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
3057   if( *pArg<0 ){
3058     *pArg = (pFile->ctrlFlags & mask)!=0;
3059   }else if( (*pArg)==0 ){
3060     pFile->ctrlFlags &= ~mask;
3061   }else{
3062     pFile->ctrlFlags |= mask;
3063   }
3064 }
3065 
3066 /* Forward references to VFS helper methods used for temporary files */
3067 static int winGetTempname(sqlite3_vfs *, char **);
3068 static int winIsDir(const void *);
3069 static BOOL winIsDriveLetterAndColon(const char *);
3070 
3071 /*
3072 ** Control and query of the open file handle.
3073 */
3074 static int winFileControl(sqlite3_file *id, int op, void *pArg){
3075   winFile *pFile = (winFile*)id;
3076   OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
3077   switch( op ){
3078     case SQLITE_FCNTL_LOCKSTATE: {
3079       *(int*)pArg = pFile->locktype;
3080       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3081       return SQLITE_OK;
3082     }
3083     case SQLITE_LAST_ERRNO: {
3084       *(int*)pArg = (int)pFile->lastErrno;
3085       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3086       return SQLITE_OK;
3087     }
3088     case SQLITE_FCNTL_CHUNK_SIZE: {
3089       pFile->szChunk = *(int *)pArg;
3090       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3091       return SQLITE_OK;
3092     }
3093     case SQLITE_FCNTL_SIZE_HINT: {
3094       if( pFile->szChunk>0 ){
3095         sqlite3_int64 oldSz;
3096         int rc = winFileSize(id, &oldSz);
3097         if( rc==SQLITE_OK ){
3098           sqlite3_int64 newSz = *(sqlite3_int64*)pArg;
3099           if( newSz>oldSz ){
3100             SimulateIOErrorBenign(1);
3101             rc = winTruncate(id, newSz);
3102             SimulateIOErrorBenign(0);
3103           }
3104         }
3105         OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3106         return rc;
3107       }
3108       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3109       return SQLITE_OK;
3110     }
3111     case SQLITE_FCNTL_PERSIST_WAL: {
3112       winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
3113       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3114       return SQLITE_OK;
3115     }
3116     case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
3117       winModeBit(pFile, WINFILE_PSOW, (int*)pArg);
3118       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3119       return SQLITE_OK;
3120     }
3121     case SQLITE_FCNTL_VFSNAME: {
3122       *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
3123       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3124       return SQLITE_OK;
3125     }
3126     case SQLITE_FCNTL_WIN32_AV_RETRY: {
3127       int *a = (int*)pArg;
3128       if( a[0]>0 ){
3129         winIoerrRetry = a[0];
3130       }else{
3131         a[0] = winIoerrRetry;
3132       }
3133       if( a[1]>0 ){
3134         winIoerrRetryDelay = a[1];
3135       }else{
3136         a[1] = winIoerrRetryDelay;
3137       }
3138       OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
3139       return SQLITE_OK;
3140     }
3141     case SQLITE_FCNTL_TEMPFILENAME: {
3142       char *zTFile = 0;
3143       int rc = winGetTempname(pFile->pVfs, &zTFile);
3144       if( rc==SQLITE_OK ){
3145         *(char**)pArg = zTFile;
3146       }
3147       OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3148       return rc;
3149     }
3150 #if SQLITE_MAX_MMAP_SIZE>0
3151     case SQLITE_FCNTL_MMAP_SIZE: {
3152       i64 newLimit = *(i64*)pArg;
3153       int rc = SQLITE_OK;
3154       if( newLimit>sqlite3GlobalConfig.mxMmap ){
3155         newLimit = sqlite3GlobalConfig.mxMmap;
3156       }
3157       *(i64*)pArg = pFile->mmapSizeMax;
3158       if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
3159         pFile->mmapSizeMax = newLimit;
3160         if( pFile->mmapSize>0 ){
3161           winUnmapfile(pFile);
3162           rc = winMapfile(pFile, -1);
3163         }
3164       }
3165       OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
3166       return rc;
3167     }
3168 #endif
3169   }
3170   OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
3171   return SQLITE_NOTFOUND;
3172 }
3173 
3174 /*
3175 ** Return the sector size in bytes of the underlying block device for
3176 ** the specified file. This is almost always 512 bytes, but may be
3177 ** larger for some devices.
3178 **
3179 ** SQLite code assumes this function cannot fail. It also assumes that
3180 ** if two files are created in the same file-system directory (i.e.
3181 ** a database and its journal file) that the sector size will be the
3182 ** same for both.
3183 */
3184 static int winSectorSize(sqlite3_file *id){
3185   (void)id;
3186   return SQLITE_DEFAULT_SECTOR_SIZE;
3187 }
3188 
3189 /*
3190 ** Return a vector of device characteristics.
3191 */
3192 static int winDeviceCharacteristics(sqlite3_file *id){
3193   winFile *p = (winFile*)id;
3194   return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
3195          ((p->ctrlFlags & WINFILE_PSOW)?SQLITE_IOCAP_POWERSAFE_OVERWRITE:0);
3196 }
3197 
3198 /*
3199 ** Windows will only let you create file view mappings
3200 ** on allocation size granularity boundaries.
3201 ** During sqlite3_os_init() we do a GetSystemInfo()
3202 ** to get the granularity size.
3203 */
3204 SYSTEM_INFO winSysInfo;
3205 
3206 #ifndef SQLITE_OMIT_WAL
3207 
3208 /*
3209 ** Helper functions to obtain and relinquish the global mutex. The
3210 ** global mutex is used to protect the winLockInfo objects used by
3211 ** this file, all of which may be shared by multiple threads.
3212 **
3213 ** Function winShmMutexHeld() is used to assert() that the global mutex
3214 ** is held when required. This function is only used as part of assert()
3215 ** statements. e.g.
3216 **
3217 **   winShmEnterMutex()
3218 **     assert( winShmMutexHeld() );
3219 **   winShmLeaveMutex()
3220 */
3221 static void winShmEnterMutex(void){
3222   sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
3223 }
3224 static void winShmLeaveMutex(void){
3225   sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
3226 }
3227 #ifndef NDEBUG
3228 static int winShmMutexHeld(void) {
3229   return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
3230 }
3231 #endif
3232 
3233 /*
3234 ** Object used to represent a single file opened and mmapped to provide
3235 ** shared memory.  When multiple threads all reference the same
3236 ** log-summary, each thread has its own winFile object, but they all
3237 ** point to a single instance of this object.  In other words, each
3238 ** log-summary is opened only once per process.
3239 **
3240 ** winShmMutexHeld() must be true when creating or destroying
3241 ** this object or while reading or writing the following fields:
3242 **
3243 **      nRef
3244 **      pNext
3245 **
3246 ** The following fields are read-only after the object is created:
3247 **
3248 **      fid
3249 **      zFilename
3250 **
3251 ** Either winShmNode.mutex must be held or winShmNode.nRef==0 and
3252 ** winShmMutexHeld() is true when reading or writing any other field
3253 ** in this structure.
3254 **
3255 */
3256 struct winShmNode {
3257   sqlite3_mutex *mutex;      /* Mutex to access this object */
3258   char *zFilename;           /* Name of the file */
3259   winFile hFile;             /* File handle from winOpen */
3260 
3261   int szRegion;              /* Size of shared-memory regions */
3262   int nRegion;               /* Size of array apRegion */
3263   struct ShmRegion {
3264     HANDLE hMap;             /* File handle from CreateFileMapping */
3265     void *pMap;
3266   } *aRegion;
3267   DWORD lastErrno;           /* The Windows errno from the last I/O error */
3268 
3269   int nRef;                  /* Number of winShm objects pointing to this */
3270   winShm *pFirst;            /* All winShm objects pointing to this */
3271   winShmNode *pNext;         /* Next in list of all winShmNode objects */
3272 #ifdef SQLITE_DEBUG
3273   u8 nextShmId;              /* Next available winShm.id value */
3274 #endif
3275 };
3276 
3277 /*
3278 ** A global array of all winShmNode objects.
3279 **
3280 ** The winShmMutexHeld() must be true while reading or writing this list.
3281 */
3282 static winShmNode *winShmNodeList = 0;
3283 
3284 /*
3285 ** Structure used internally by this VFS to record the state of an
3286 ** open shared memory connection.
3287 **
3288 ** The following fields are initialized when this object is created and
3289 ** are read-only thereafter:
3290 **
3291 **    winShm.pShmNode
3292 **    winShm.id
3293 **
3294 ** All other fields are read/write.  The winShm.pShmNode->mutex must be held
3295 ** while accessing any read/write fields.
3296 */
3297 struct winShm {
3298   winShmNode *pShmNode;      /* The underlying winShmNode object */
3299   winShm *pNext;             /* Next winShm with the same winShmNode */
3300   u8 hasMutex;               /* True if holding the winShmNode mutex */
3301   u16 sharedMask;            /* Mask of shared locks held */
3302   u16 exclMask;              /* Mask of exclusive locks held */
3303 #ifdef SQLITE_DEBUG
3304   u8 id;                     /* Id of this connection with its winShmNode */
3305 #endif
3306 };
3307 
3308 /*
3309 ** Constants used for locking
3310 */
3311 #define WIN_SHM_BASE   ((22+SQLITE_SHM_NLOCK)*4)        /* first lock byte */
3312 #define WIN_SHM_DMS    (WIN_SHM_BASE+SQLITE_SHM_NLOCK)  /* deadman switch */
3313 
3314 /*
3315 ** Apply advisory locks for all n bytes beginning at ofst.
3316 */
3317 #define _SHM_UNLCK  1
3318 #define _SHM_RDLCK  2
3319 #define _SHM_WRLCK  3
3320 static int winShmSystemLock(
3321   winShmNode *pFile,    /* Apply locks to this open shared-memory segment */
3322   int lockType,         /* _SHM_UNLCK, _SHM_RDLCK, or _SHM_WRLCK */
3323   int ofst,             /* Offset to first byte to be locked/unlocked */
3324   int nByte             /* Number of bytes to lock or unlock */
3325 ){
3326   int rc = 0;           /* Result code form Lock/UnlockFileEx() */
3327 
3328   /* Access to the winShmNode object is serialized by the caller */
3329   assert( sqlite3_mutex_held(pFile->mutex) || pFile->nRef==0 );
3330 
3331   OSTRACE(("SHM-LOCK file=%p, lock=%d, offset=%d, size=%d\n",
3332            pFile->hFile.h, lockType, ofst, nByte));
3333 
3334   /* Release/Acquire the system-level lock */
3335   if( lockType==_SHM_UNLCK ){
3336     rc = winUnlockFile(&pFile->hFile.h, ofst, 0, nByte, 0);
3337   }else{
3338     /* Initialize the locking parameters */
3339     DWORD dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
3340     if( lockType == _SHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
3341     rc = winLockFile(&pFile->hFile.h, dwFlags, ofst, 0, nByte, 0);
3342   }
3343 
3344   if( rc!= 0 ){
3345     rc = SQLITE_OK;
3346   }else{
3347     pFile->lastErrno =  osGetLastError();
3348     rc = SQLITE_BUSY;
3349   }
3350 
3351   OSTRACE(("SHM-LOCK file=%p, func=%s, errno=%lu, rc=%s\n",
3352            pFile->hFile.h, (lockType == _SHM_UNLCK) ? "winUnlockFile" :
3353            "winLockFile", pFile->lastErrno, sqlite3ErrName(rc)));
3354 
3355   return rc;
3356 }
3357 
3358 /* Forward references to VFS methods */
3359 static int winOpen(sqlite3_vfs*,const char*,sqlite3_file*,int,int*);
3360 static int winDelete(sqlite3_vfs *,const char*,int);
3361 
3362 /*
3363 ** Purge the winShmNodeList list of all entries with winShmNode.nRef==0.
3364 **
3365 ** This is not a VFS shared-memory method; it is a utility function called
3366 ** by VFS shared-memory methods.
3367 */
3368 static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
3369   winShmNode **pp;
3370   winShmNode *p;
3371   assert( winShmMutexHeld() );
3372   OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
3373            osGetCurrentProcessId(), deleteFlag));
3374   pp = &winShmNodeList;
3375   while( (p = *pp)!=0 ){
3376     if( p->nRef==0 ){
3377       int i;
3378       if( p->mutex ){ sqlite3_mutex_free(p->mutex); }
3379       for(i=0; i<p->nRegion; i++){
3380         BOOL bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
3381         OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
3382                  osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
3383         UNUSED_VARIABLE_VALUE(bRc);
3384         bRc = osCloseHandle(p->aRegion[i].hMap);
3385         OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
3386                  osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
3387         UNUSED_VARIABLE_VALUE(bRc);
3388       }
3389       if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
3390         SimulateIOErrorBenign(1);
3391         winClose((sqlite3_file *)&p->hFile);
3392         SimulateIOErrorBenign(0);
3393       }
3394       if( deleteFlag ){
3395         SimulateIOErrorBenign(1);
3396         sqlite3BeginBenignMalloc();
3397         winDelete(pVfs, p->zFilename, 0);
3398         sqlite3EndBenignMalloc();
3399         SimulateIOErrorBenign(0);
3400       }
3401       *pp = p->pNext;
3402       sqlite3_free(p->aRegion);
3403       sqlite3_free(p);
3404     }else{
3405       pp = &p->pNext;
3406     }
3407   }
3408 }
3409 
3410 /*
3411 ** Open the shared-memory area associated with database file pDbFd.
3412 **
3413 ** When opening a new shared-memory file, if no other instances of that
3414 ** file are currently open, in this process or in other processes, then
3415 ** the file must be truncated to zero length or have its header cleared.
3416 */
3417 static int winOpenSharedMemory(winFile *pDbFd){
3418   struct winShm *p;                  /* The connection to be opened */
3419   struct winShmNode *pShmNode = 0;   /* The underlying mmapped file */
3420   int rc;                            /* Result code */
3421   struct winShmNode *pNew;           /* Newly allocated winShmNode */
3422   int nName;                         /* Size of zName in bytes */
3423 
3424   assert( pDbFd->pShm==0 );    /* Not previously opened */
3425 
3426   /* Allocate space for the new sqlite3_shm object.  Also speculatively
3427   ** allocate space for a new winShmNode and filename.
3428   */
3429   p = sqlite3MallocZero( sizeof(*p) );
3430   if( p==0 ) return SQLITE_IOERR_NOMEM;
3431   nName = sqlite3Strlen30(pDbFd->zPath);
3432   pNew = sqlite3MallocZero( sizeof(*pShmNode) + nName + 17 );
3433   if( pNew==0 ){
3434     sqlite3_free(p);
3435     return SQLITE_IOERR_NOMEM;
3436   }
3437   pNew->zFilename = (char*)&pNew[1];
3438   sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
3439   sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename);
3440 
3441   /* Look to see if there is an existing winShmNode that can be used.
3442   ** If no matching winShmNode currently exists, create a new one.
3443   */
3444   winShmEnterMutex();
3445   for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){
3446     /* TBD need to come up with better match here.  Perhaps
3447     ** use FILE_ID_BOTH_DIR_INFO Structure.
3448     */
3449     if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break;
3450   }
3451   if( pShmNode ){
3452     sqlite3_free(pNew);
3453   }else{
3454     pShmNode = pNew;
3455     pNew = 0;
3456     ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE;
3457     pShmNode->pNext = winShmNodeList;
3458     winShmNodeList = pShmNode;
3459 
3460     pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
3461     if( pShmNode->mutex==0 ){
3462       rc = SQLITE_IOERR_NOMEM;
3463       goto shm_open_err;
3464     }
3465 
3466     rc = winOpen(pDbFd->pVfs,
3467                  pShmNode->zFilename,             /* Name of the file (UTF-8) */
3468                  (sqlite3_file*)&pShmNode->hFile,  /* File handle here */
3469                  SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE,
3470                  0);
3471     if( SQLITE_OK!=rc ){
3472       goto shm_open_err;
3473     }
3474 
3475     /* Check to see if another process is holding the dead-man switch.
3476     ** If not, truncate the file to zero length.
3477     */
3478     if( winShmSystemLock(pShmNode, _SHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){
3479       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0);
3480       if( rc!=SQLITE_OK ){
3481         rc = winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
3482                          "winOpenShm", pDbFd->zPath);
3483       }
3484     }
3485     if( rc==SQLITE_OK ){
3486       winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
3487       rc = winShmSystemLock(pShmNode, _SHM_RDLCK, WIN_SHM_DMS, 1);
3488     }
3489     if( rc ) goto shm_open_err;
3490   }
3491 
3492   /* Make the new connection a child of the winShmNode */
3493   p->pShmNode = pShmNode;
3494 #ifdef SQLITE_DEBUG
3495   p->id = pShmNode->nextShmId++;
3496 #endif
3497   pShmNode->nRef++;
3498   pDbFd->pShm = p;
3499   winShmLeaveMutex();
3500 
3501   /* The reference count on pShmNode has already been incremented under
3502   ** the cover of the winShmEnterMutex() mutex and the pointer from the
3503   ** new (struct winShm) object to the pShmNode has been set. All that is
3504   ** left to do is to link the new object into the linked list starting
3505   ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex
3506   ** mutex.
3507   */
3508   sqlite3_mutex_enter(pShmNode->mutex);
3509   p->pNext = pShmNode->pFirst;
3510   pShmNode->pFirst = p;
3511   sqlite3_mutex_leave(pShmNode->mutex);
3512   return SQLITE_OK;
3513 
3514   /* Jump here on any error */
3515 shm_open_err:
3516   winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
3517   winShmPurge(pDbFd->pVfs, 0);      /* This call frees pShmNode if required */
3518   sqlite3_free(p);
3519   sqlite3_free(pNew);
3520   winShmLeaveMutex();
3521   return rc;
3522 }
3523 
3524 /*
3525 ** Close a connection to shared-memory.  Delete the underlying
3526 ** storage if deleteFlag is true.
3527 */
3528 static int winShmUnmap(
3529   sqlite3_file *fd,          /* Database holding shared memory */
3530   int deleteFlag             /* Delete after closing if true */
3531 ){
3532   winFile *pDbFd;       /* Database holding shared-memory */
3533   winShm *p;            /* The connection to be closed */
3534   winShmNode *pShmNode; /* The underlying shared-memory file */
3535   winShm **pp;          /* For looping over sibling connections */
3536 
3537   pDbFd = (winFile*)fd;
3538   p = pDbFd->pShm;
3539   if( p==0 ) return SQLITE_OK;
3540   pShmNode = p->pShmNode;
3541 
3542   /* Remove connection p from the set of connections associated
3543   ** with pShmNode */
3544   sqlite3_mutex_enter(pShmNode->mutex);
3545   for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
3546   *pp = p->pNext;
3547 
3548   /* Free the connection p */
3549   sqlite3_free(p);
3550   pDbFd->pShm = 0;
3551   sqlite3_mutex_leave(pShmNode->mutex);
3552 
3553   /* If pShmNode->nRef has reached 0, then close the underlying
3554   ** shared-memory file, too */
3555   winShmEnterMutex();
3556   assert( pShmNode->nRef>0 );
3557   pShmNode->nRef--;
3558   if( pShmNode->nRef==0 ){
3559     winShmPurge(pDbFd->pVfs, deleteFlag);
3560   }
3561   winShmLeaveMutex();
3562 
3563   return SQLITE_OK;
3564 }
3565 
3566 /*
3567 ** Change the lock state for a shared-memory segment.
3568 */
3569 static int winShmLock(
3570   sqlite3_file *fd,          /* Database file holding the shared memory */
3571   int ofst,                  /* First lock to acquire or release */
3572   int n,                     /* Number of locks to acquire or release */
3573   int flags                  /* What to do with the lock */
3574 ){
3575   winFile *pDbFd = (winFile*)fd;        /* Connection holding shared memory */
3576   winShm *p = pDbFd->pShm;              /* The shared memory being locked */
3577   winShm *pX;                           /* For looping over all siblings */
3578   winShmNode *pShmNode = p->pShmNode;
3579   int rc = SQLITE_OK;                   /* Result code */
3580   u16 mask;                             /* Mask of locks to take or release */
3581 
3582   assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
3583   assert( n>=1 );
3584   assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
3585        || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
3586        || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
3587        || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
3588   assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
3589 
3590   mask = (u16)((1U<<(ofst+n)) - (1U<<ofst));
3591   assert( n>1 || mask==(1<<ofst) );
3592   sqlite3_mutex_enter(pShmNode->mutex);
3593   if( flags & SQLITE_SHM_UNLOCK ){
3594     u16 allMask = 0; /* Mask of locks held by siblings */
3595 
3596     /* See if any siblings hold this same lock */
3597     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
3598       if( pX==p ) continue;
3599       assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
3600       allMask |= pX->sharedMask;
3601     }
3602 
3603     /* Unlock the system-level locks */
3604     if( (mask & allMask)==0 ){
3605       rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
3606     }else{
3607       rc = SQLITE_OK;
3608     }
3609 
3610     /* Undo the local locks */
3611     if( rc==SQLITE_OK ){
3612       p->exclMask &= ~mask;
3613       p->sharedMask &= ~mask;
3614     }
3615   }else if( flags & SQLITE_SHM_SHARED ){
3616     u16 allShared = 0;  /* Union of locks held by connections other than "p" */
3617 
3618     /* Find out which shared locks are already held by sibling connections.
3619     ** If any sibling already holds an exclusive lock, go ahead and return
3620     ** SQLITE_BUSY.
3621     */
3622     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
3623       if( (pX->exclMask & mask)!=0 ){
3624         rc = SQLITE_BUSY;
3625         break;
3626       }
3627       allShared |= pX->sharedMask;
3628     }
3629 
3630     /* Get shared locks at the system level, if necessary */
3631     if( rc==SQLITE_OK ){
3632       if( (allShared & mask)==0 ){
3633         rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
3634       }else{
3635         rc = SQLITE_OK;
3636       }
3637     }
3638 
3639     /* Get the local shared locks */
3640     if( rc==SQLITE_OK ){
3641       p->sharedMask |= mask;
3642     }
3643   }else{
3644     /* Make sure no sibling connections hold locks that will block this
3645     ** lock.  If any do, return SQLITE_BUSY right away.
3646     */
3647     for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
3648       if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
3649         rc = SQLITE_BUSY;
3650         break;
3651       }
3652     }
3653 
3654     /* Get the exclusive locks at the system level.  Then if successful
3655     ** also mark the local connection as being locked.
3656     */
3657     if( rc==SQLITE_OK ){
3658       rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
3659       if( rc==SQLITE_OK ){
3660         assert( (p->sharedMask & mask)==0 );
3661         p->exclMask |= mask;
3662       }
3663     }
3664   }
3665   sqlite3_mutex_leave(pShmNode->mutex);
3666   OSTRACE(("SHM-LOCK pid=%lu, id=%d, sharedMask=%03x, exclMask=%03x, rc=%s\n",
3667            osGetCurrentProcessId(), p->id, p->sharedMask, p->exclMask,
3668            sqlite3ErrName(rc)));
3669   return rc;
3670 }
3671 
3672 /*
3673 ** Implement a memory barrier or memory fence on shared memory.
3674 **
3675 ** All loads and stores begun before the barrier must complete before
3676 ** any load or store begun after the barrier.
3677 */
3678 static void winShmBarrier(
3679   sqlite3_file *fd          /* Database holding the shared memory */
3680 ){
3681   UNUSED_PARAMETER(fd);
3682   /* MemoryBarrier(); // does not work -- do not know why not */
3683   winShmEnterMutex();
3684   winShmLeaveMutex();
3685 }
3686 
3687 /*
3688 ** This function is called to obtain a pointer to region iRegion of the
3689 ** shared-memory associated with the database file fd. Shared-memory regions
3690 ** are numbered starting from zero. Each shared-memory region is szRegion
3691 ** bytes in size.
3692 **
3693 ** If an error occurs, an error code is returned and *pp is set to NULL.
3694 **
3695 ** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
3696 ** region has not been allocated (by any client, including one running in a
3697 ** separate process), then *pp is set to NULL and SQLITE_OK returned. If
3698 ** isWrite is non-zero and the requested shared-memory region has not yet
3699 ** been allocated, it is allocated by this function.
3700 **
3701 ** If the shared-memory region has already been allocated or is allocated by
3702 ** this call as described above, then it is mapped into this processes
3703 ** address space (if it is not already), *pp is set to point to the mapped
3704 ** memory and SQLITE_OK returned.
3705 */
3706 static int winShmMap(
3707   sqlite3_file *fd,               /* Handle open on database file */
3708   int iRegion,                    /* Region to retrieve */
3709   int szRegion,                   /* Size of regions */
3710   int isWrite,                    /* True to extend file if necessary */
3711   void volatile **pp              /* OUT: Mapped memory */
3712 ){
3713   winFile *pDbFd = (winFile*)fd;
3714   winShm *p = pDbFd->pShm;
3715   winShmNode *pShmNode;
3716   int rc = SQLITE_OK;
3717 
3718   if( !p ){
3719     rc = winOpenSharedMemory(pDbFd);
3720     if( rc!=SQLITE_OK ) return rc;
3721     p = pDbFd->pShm;
3722   }
3723   pShmNode = p->pShmNode;
3724 
3725   sqlite3_mutex_enter(pShmNode->mutex);
3726   assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
3727 
3728   if( pShmNode->nRegion<=iRegion ){
3729     struct ShmRegion *apNew;           /* New aRegion[] array */
3730     int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
3731     sqlite3_int64 sz;                  /* Current size of wal-index file */
3732 
3733     pShmNode->szRegion = szRegion;
3734 
3735     /* The requested region is not mapped into this processes address space.
3736     ** Check to see if it has been allocated (i.e. if the wal-index file is
3737     ** large enough to contain the requested region).
3738     */
3739     rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
3740     if( rc!=SQLITE_OK ){
3741       rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
3742                        "winShmMap1", pDbFd->zPath);
3743       goto shmpage_out;
3744     }
3745 
3746     if( sz<nByte ){
3747       /* The requested memory region does not exist. If isWrite is set to
3748       ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
3749       **
3750       ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
3751       ** the requested memory region.
3752       */
3753       if( !isWrite ) goto shmpage_out;
3754       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
3755       if( rc!=SQLITE_OK ){
3756         rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
3757                          "winShmMap2", pDbFd->zPath);
3758         goto shmpage_out;
3759       }
3760     }
3761 
3762     /* Map the requested memory region into this processes address space. */
3763     apNew = (struct ShmRegion *)sqlite3_realloc(
3764         pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
3765     );
3766     if( !apNew ){
3767       rc = SQLITE_IOERR_NOMEM;
3768       goto shmpage_out;
3769     }
3770     pShmNode->aRegion = apNew;
3771 
3772     while( pShmNode->nRegion<=iRegion ){
3773       HANDLE hMap = NULL;         /* file-mapping handle */
3774       void *pMap = 0;             /* Mapped memory region */
3775 
3776 #if SQLITE_OS_WINRT
3777       hMap = osCreateFileMappingFromApp(pShmNode->hFile.h,
3778           NULL, PAGE_READWRITE, nByte, NULL
3779       );
3780 #elif defined(SQLITE_WIN32_HAS_WIDE)
3781       hMap = osCreateFileMappingW(pShmNode->hFile.h,
3782           NULL, PAGE_READWRITE, 0, nByte, NULL
3783       );
3784 #elif defined(SQLITE_WIN32_HAS_ANSI)
3785       hMap = osCreateFileMappingA(pShmNode->hFile.h,
3786           NULL, PAGE_READWRITE, 0, nByte, NULL
3787       );
3788 #endif
3789       OSTRACE(("SHM-MAP-CREATE pid=%lu, region=%d, size=%d, rc=%s\n",
3790                osGetCurrentProcessId(), pShmNode->nRegion, nByte,
3791                hMap ? "ok" : "failed"));
3792       if( hMap ){
3793         int iOffset = pShmNode->nRegion*szRegion;
3794         int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
3795 #if SQLITE_OS_WINRT
3796         pMap = osMapViewOfFileFromApp(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
3797             iOffset - iOffsetShift, szRegion + iOffsetShift
3798         );
3799 #else
3800         pMap = osMapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
3801             0, iOffset - iOffsetShift, szRegion + iOffsetShift
3802         );
3803 #endif
3804         OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
3805                  osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
3806                  szRegion, pMap ? "ok" : "failed"));
3807       }
3808       if( !pMap ){
3809         pShmNode->lastErrno = osGetLastError();
3810         rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
3811                          "winShmMap3", pDbFd->zPath);
3812         if( hMap ) osCloseHandle(hMap);
3813         goto shmpage_out;
3814       }
3815 
3816       pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
3817       pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
3818       pShmNode->nRegion++;
3819     }
3820   }
3821 
3822 shmpage_out:
3823   if( pShmNode->nRegion>iRegion ){
3824     int iOffset = iRegion*szRegion;
3825     int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
3826     char *p = (char *)pShmNode->aRegion[iRegion].pMap;
3827     *pp = (void *)&p[iOffsetShift];
3828   }else{
3829     *pp = 0;
3830   }
3831   sqlite3_mutex_leave(pShmNode->mutex);
3832   return rc;
3833 }
3834 
3835 #else
3836 # define winShmMap     0
3837 # define winShmLock    0
3838 # define winShmBarrier 0
3839 # define winShmUnmap   0
3840 #endif /* #ifndef SQLITE_OMIT_WAL */
3841 
3842 /*
3843 ** Cleans up the mapped region of the specified file, if any.
3844 */
3845 #if SQLITE_MAX_MMAP_SIZE>0
3846 static int winUnmapfile(winFile *pFile){
3847   assert( pFile!=0 );
3848   OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, pMapRegion=%p, "
3849            "mmapSize=%lld, mmapSizeActual=%lld, mmapSizeMax=%lld\n",
3850            osGetCurrentProcessId(), pFile, pFile->hMap, pFile->pMapRegion,
3851            pFile->mmapSize, pFile->mmapSizeActual, pFile->mmapSizeMax));
3852   if( pFile->pMapRegion ){
3853     if( !osUnmapViewOfFile(pFile->pMapRegion) ){
3854       pFile->lastErrno = osGetLastError();
3855       OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
3856                "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
3857                pFile->pMapRegion));
3858       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
3859                          "winUnmapfile1", pFile->zPath);
3860     }
3861     pFile->pMapRegion = 0;
3862     pFile->mmapSize = 0;
3863     pFile->mmapSizeActual = 0;
3864   }
3865   if( pFile->hMap!=NULL ){
3866     if( !osCloseHandle(pFile->hMap) ){
3867       pFile->lastErrno = osGetLastError();
3868       OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
3869                osGetCurrentProcessId(), pFile, pFile->hMap));
3870       return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
3871                          "winUnmapfile2", pFile->zPath);
3872     }
3873     pFile->hMap = NULL;
3874   }
3875   OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
3876            osGetCurrentProcessId(), pFile));
3877   return SQLITE_OK;
3878 }
3879 
3880 /*
3881 ** Memory map or remap the file opened by file-descriptor pFd (if the file
3882 ** is already mapped, the existing mapping is replaced by the new). Or, if
3883 ** there already exists a mapping for this file, and there are still
3884 ** outstanding xFetch() references to it, this function is a no-op.
3885 **
3886 ** If parameter nByte is non-negative, then it is the requested size of
3887 ** the mapping to create. Otherwise, if nByte is less than zero, then the
3888 ** requested size is the size of the file on disk. The actual size of the
3889 ** created mapping is either the requested size or the value configured
3890 ** using SQLITE_FCNTL_MMAP_SIZE, whichever is smaller.
3891 **
3892 ** SQLITE_OK is returned if no error occurs (even if the mapping is not
3893 ** recreated as a result of outstanding references) or an SQLite error
3894 ** code otherwise.
3895 */
3896 static int winMapfile(winFile *pFd, sqlite3_int64 nByte){
3897   sqlite3_int64 nMap = nByte;
3898   int rc;
3899 
3900   assert( nMap>=0 || pFd->nFetchOut==0 );
3901   OSTRACE(("MAP-FILE pid=%lu, pFile=%p, size=%lld\n",
3902            osGetCurrentProcessId(), pFd, nByte));
3903 
3904   if( pFd->nFetchOut>0 ) return SQLITE_OK;
3905 
3906   if( nMap<0 ){
3907     rc = winFileSize((sqlite3_file*)pFd, &nMap);
3908     if( rc ){
3909       OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_IOERR_FSTAT\n",
3910                osGetCurrentProcessId(), pFd));
3911       return SQLITE_IOERR_FSTAT;
3912     }
3913   }
3914   if( nMap>pFd->mmapSizeMax ){
3915     nMap = pFd->mmapSizeMax;
3916   }
3917   nMap &= ~(sqlite3_int64)(winSysInfo.dwPageSize - 1);
3918 
3919   if( nMap==0 && pFd->mmapSize>0 ){
3920     winUnmapfile(pFd);
3921   }
3922   if( nMap!=pFd->mmapSize ){
3923     void *pNew = 0;
3924     DWORD protect = PAGE_READONLY;
3925     DWORD flags = FILE_MAP_READ;
3926 
3927     winUnmapfile(pFd);
3928     if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
3929       protect = PAGE_READWRITE;
3930       flags |= FILE_MAP_WRITE;
3931     }
3932 #if SQLITE_OS_WINRT
3933     pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
3934 #elif defined(SQLITE_WIN32_HAS_WIDE)
3935     pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
3936                                 (DWORD)((nMap>>32) & 0xffffffff),
3937                                 (DWORD)(nMap & 0xffffffff), NULL);
3938 #elif defined(SQLITE_WIN32_HAS_ANSI)
3939     pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
3940                                 (DWORD)((nMap>>32) & 0xffffffff),
3941                                 (DWORD)(nMap & 0xffffffff), NULL);
3942 #endif
3943     if( pFd->hMap==NULL ){
3944       pFd->lastErrno = osGetLastError();
3945       rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
3946                        "winMapfile1", pFd->zPath);
3947       /* Log the error, but continue normal operation using xRead/xWrite */
3948       OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=%s\n",
3949                osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
3950       return SQLITE_OK;
3951     }
3952     assert( (nMap % winSysInfo.dwPageSize)==0 );
3953     assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
3954 #if SQLITE_OS_WINRT
3955     pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
3956 #else
3957     pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
3958 #endif
3959     if( pNew==NULL ){
3960       osCloseHandle(pFd->hMap);
3961       pFd->hMap = NULL;
3962       pFd->lastErrno = osGetLastError();
3963       rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
3964                        "winMapfile2", pFd->zPath);
3965       /* Log the error, but continue normal operation using xRead/xWrite */
3966       OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=%s\n",
3967                osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
3968       return SQLITE_OK;
3969     }
3970     pFd->pMapRegion = pNew;
3971     pFd->mmapSize = nMap;
3972     pFd->mmapSizeActual = nMap;
3973   }
3974 
3975   OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
3976            osGetCurrentProcessId(), pFd));
3977   return SQLITE_OK;
3978 }
3979 #endif /* SQLITE_MAX_MMAP_SIZE>0 */
3980 
3981 /*
3982 ** If possible, return a pointer to a mapping of file fd starting at offset
3983 ** iOff. The mapping must be valid for at least nAmt bytes.
3984 **
3985 ** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
3986 ** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
3987 ** Finally, if an error does occur, return an SQLite error code. The final
3988 ** value of *pp is undefined in this case.
3989 **
3990 ** If this function does return a pointer, the caller must eventually
3991 ** release the reference by calling winUnfetch().
3992 */
3993 static int winFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
3994 #if SQLITE_MAX_MMAP_SIZE>0
3995   winFile *pFd = (winFile*)fd;   /* The underlying database file */
3996 #endif
3997   *pp = 0;
3998 
3999   OSTRACE(("FETCH pid=%lu, pFile=%p, offset=%lld, amount=%d, pp=%p\n",
4000            osGetCurrentProcessId(), fd, iOff, nAmt, pp));
4001 
4002 #if SQLITE_MAX_MMAP_SIZE>0
4003   if( pFd->mmapSizeMax>0 ){
4004     if( pFd->pMapRegion==0 ){
4005       int rc = winMapfile(pFd, -1);
4006       if( rc!=SQLITE_OK ){
4007         OSTRACE(("FETCH pid=%lu, pFile=%p, rc=%s\n",
4008                  osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
4009         return rc;
4010       }
4011     }
4012     if( pFd->mmapSize >= iOff+nAmt ){
4013       *pp = &((u8 *)pFd->pMapRegion)[iOff];
4014       pFd->nFetchOut++;
4015     }
4016   }
4017 #endif
4018 
4019   OSTRACE(("FETCH pid=%lu, pFile=%p, pp=%p, *pp=%p, rc=SQLITE_OK\n",
4020            osGetCurrentProcessId(), fd, pp, *pp));
4021   return SQLITE_OK;
4022 }
4023 
4024 /*
4025 ** If the third argument is non-NULL, then this function releases a
4026 ** reference obtained by an earlier call to winFetch(). The second
4027 ** argument passed to this function must be the same as the corresponding
4028 ** argument that was passed to the winFetch() invocation.
4029 **
4030 ** Or, if the third argument is NULL, then this function is being called
4031 ** to inform the VFS layer that, according to POSIX, any existing mapping
4032 ** may now be invalid and should be unmapped.
4033 */
4034 static int winUnfetch(sqlite3_file *fd, i64 iOff, void *p){
4035 #if SQLITE_MAX_MMAP_SIZE>0
4036   winFile *pFd = (winFile*)fd;   /* The underlying database file */
4037 
4038   /* If p==0 (unmap the entire file) then there must be no outstanding
4039   ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
4040   ** then there must be at least one outstanding.  */
4041   assert( (p==0)==(pFd->nFetchOut==0) );
4042 
4043   /* If p!=0, it must match the iOff value. */
4044   assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
4045 
4046   OSTRACE(("UNFETCH pid=%lu, pFile=%p, offset=%lld, p=%p\n",
4047            osGetCurrentProcessId(), pFd, iOff, p));
4048 
4049   if( p ){
4050     pFd->nFetchOut--;
4051   }else{
4052     /* FIXME:  If Windows truly always prevents truncating or deleting a
4053     ** file while a mapping is held, then the following winUnmapfile() call
4054     ** is unnecessary can can be omitted - potentially improving
4055     ** performance.  */
4056     winUnmapfile(pFd);
4057   }
4058 
4059   assert( pFd->nFetchOut>=0 );
4060 #endif
4061 
4062   OSTRACE(("UNFETCH pid=%lu, pFile=%p, rc=SQLITE_OK\n",
4063            osGetCurrentProcessId(), fd));
4064   return SQLITE_OK;
4065 }
4066 
4067 /*
4068 ** Here ends the implementation of all sqlite3_file methods.
4069 **
4070 ********************** End sqlite3_file Methods *******************************
4071 ******************************************************************************/
4072 
4073 /*
4074 ** This vector defines all the methods that can operate on an
4075 ** sqlite3_file for win32.
4076 */
4077 static const sqlite3_io_methods winIoMethod = {
4078   3,                              /* iVersion */
4079   winClose,                       /* xClose */
4080   winRead,                        /* xRead */
4081   winWrite,                       /* xWrite */
4082   winTruncate,                    /* xTruncate */
4083   winSync,                        /* xSync */
4084   winFileSize,                    /* xFileSize */
4085   winLock,                        /* xLock */
4086   winUnlock,                      /* xUnlock */
4087   winCheckReservedLock,           /* xCheckReservedLock */
4088   winFileControl,                 /* xFileControl */
4089   winSectorSize,                  /* xSectorSize */
4090   winDeviceCharacteristics,       /* xDeviceCharacteristics */
4091   winShmMap,                      /* xShmMap */
4092   winShmLock,                     /* xShmLock */
4093   winShmBarrier,                  /* xShmBarrier */
4094   winShmUnmap,                    /* xShmUnmap */
4095   winFetch,                       /* xFetch */
4096   winUnfetch                      /* xUnfetch */
4097 };
4098 
4099 /****************************************************************************
4100 **************************** sqlite3_vfs methods ****************************
4101 **
4102 ** This division contains the implementation of methods on the
4103 ** sqlite3_vfs object.
4104 */
4105 
4106 #if defined(__CYGWIN__)
4107 /*
4108 ** Convert a filename from whatever the underlying operating system
4109 ** supports for filenames into UTF-8.  Space to hold the result is
4110 ** obtained from malloc and must be freed by the calling function.
4111 */
4112 static char *winConvertToUtf8Filename(const void *zFilename){
4113   char *zConverted = 0;
4114   if( osIsNT() ){
4115     zConverted = winUnicodeToUtf8(zFilename);
4116   }
4117 #ifdef SQLITE_WIN32_HAS_ANSI
4118   else{
4119     zConverted = sqlite3_win32_mbcs_to_utf8(zFilename);
4120   }
4121 #endif
4122   /* caller will handle out of memory */
4123   return zConverted;
4124 }
4125 #endif
4126 
4127 /*
4128 ** Convert a UTF-8 filename into whatever form the underlying
4129 ** operating system wants filenames in.  Space to hold the result
4130 ** is obtained from malloc and must be freed by the calling
4131 ** function.
4132 */
4133 static void *winConvertFromUtf8Filename(const char *zFilename){
4134   void *zConverted = 0;
4135   if( osIsNT() ){
4136     zConverted = winUtf8ToUnicode(zFilename);
4137   }
4138 #ifdef SQLITE_WIN32_HAS_ANSI
4139   else{
4140     zConverted = sqlite3_win32_utf8_to_mbcs(zFilename);
4141   }
4142 #endif
4143   /* caller will handle out of memory */
4144   return zConverted;
4145 }
4146 
4147 /*
4148 ** This function returns non-zero if the specified UTF-8 string buffer
4149 ** ends with a directory separator character or one was successfully
4150 ** added to it.
4151 */
4152 static int winMakeEndInDirSep(int nBuf, char *zBuf){
4153   if( zBuf ){
4154     int nLen = sqlite3Strlen30(zBuf);
4155     if( nLen>0 ){
4156       if( winIsDirSep(zBuf[nLen-1]) ){
4157         return 1;
4158       }else if( nLen+1<nBuf ){
4159         zBuf[nLen] = winGetDirSep();
4160         zBuf[nLen+1] = '\0';
4161         return 1;
4162       }
4163     }
4164   }
4165   return 0;
4166 }
4167 
4168 /*
4169 ** Create a temporary file name and store the resulting pointer into pzBuf.
4170 ** The pointer returned in pzBuf must be freed via sqlite3_free().
4171 */
4172 static int winGetTempname(sqlite3_vfs *pVfs, char **pzBuf){
4173   static char zChars[] =
4174     "abcdefghijklmnopqrstuvwxyz"
4175     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
4176     "0123456789";
4177   size_t i, j;
4178   int nPre = sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX);
4179   int nMax, nBuf, nDir, nLen;
4180   char *zBuf;
4181 
4182   /* It's odd to simulate an io-error here, but really this is just
4183   ** using the io-error infrastructure to test that SQLite handles this
4184   ** function failing.
4185   */
4186   SimulateIOError( return SQLITE_IOERR );
4187 
4188   /* Allocate a temporary buffer to store the fully qualified file
4189   ** name for the temporary file.  If this fails, we cannot continue.
4190   */
4191   nMax = pVfs->mxPathname; nBuf = nMax + 2;
4192   zBuf = sqlite3MallocZero( nBuf );
4193   if( !zBuf ){
4194     OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4195     return SQLITE_IOERR_NOMEM;
4196   }
4197 
4198   /* Figure out the effective temporary directory.  First, check if one
4199   ** has been explicitly set by the application; otherwise, use the one
4200   ** configured by the operating system.
4201   */
4202   nDir = nMax - (nPre + 15);
4203   assert( nDir>0 );
4204   if( sqlite3_temp_directory ){
4205     int nDirLen = sqlite3Strlen30(sqlite3_temp_directory);
4206     if( nDirLen>0 ){
4207       if( !winIsDirSep(sqlite3_temp_directory[nDirLen-1]) ){
4208         nDirLen++;
4209       }
4210       if( nDirLen>nDir ){
4211         sqlite3_free(zBuf);
4212         OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4213         return winLogError(SQLITE_ERROR, 0, "winGetTempname1", 0);
4214       }
4215       sqlite3_snprintf(nMax, zBuf, "%s", sqlite3_temp_directory);
4216     }
4217   }
4218 #if defined(__CYGWIN__)
4219   else{
4220     static const char *azDirs[] = {
4221        0, /* getenv("SQLITE_TMPDIR") */
4222        0, /* getenv("TMPDIR") */
4223        0, /* getenv("TMP") */
4224        0, /* getenv("TEMP") */
4225        0, /* getenv("USERPROFILE") */
4226        "/var/tmp",
4227        "/usr/tmp",
4228        "/tmp",
4229        ".",
4230        0        /* List terminator */
4231     };
4232     unsigned int i;
4233     const char *zDir = 0;
4234 
4235     if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
4236     if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
4237     if( !azDirs[2] ) azDirs[2] = getenv("TMP");
4238     if( !azDirs[3] ) azDirs[3] = getenv("TEMP");
4239     if( !azDirs[4] ) azDirs[4] = getenv("USERPROFILE");
4240     for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
4241       void *zConverted;
4242       if( zDir==0 ) continue;
4243       /* If the path starts with a drive letter followed by the colon
4244       ** character, assume it is already a native Win32 path; otherwise,
4245       ** it must be converted to a native Win32 path via the Cygwin API
4246       ** prior to using it.
4247       */
4248       if( winIsDriveLetterAndColon(zDir) ){
4249         zConverted = winConvertFromUtf8Filename(zDir);
4250         if( !zConverted ){
4251           sqlite3_free(zBuf);
4252           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4253           return SQLITE_IOERR_NOMEM;
4254         }
4255         if( winIsDir(zConverted) ){
4256           sqlite3_snprintf(nMax, zBuf, "%s", zDir);
4257           sqlite3_free(zConverted);
4258           break;
4259         }
4260         sqlite3_free(zConverted);
4261       }else{
4262         zConverted = sqlite3MallocZero( nMax+1 );
4263         if( !zConverted ){
4264           sqlite3_free(zBuf);
4265           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4266           return SQLITE_IOERR_NOMEM;
4267         }
4268         if( cygwin_conv_path(
4269                 osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A, zDir,
4270                 zConverted, nMax+1)<0 ){
4271           sqlite3_free(zConverted);
4272           sqlite3_free(zBuf);
4273           OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_CONVPATH\n"));
4274           return winLogError(SQLITE_IOERR_CONVPATH, (DWORD)errno,
4275                              "winGetTempname2", zDir);
4276         }
4277         if( winIsDir(zConverted) ){
4278           /* At this point, we know the candidate directory exists and should
4279           ** be used.  However, we may need to convert the string containing
4280           ** its name into UTF-8 (i.e. if it is UTF-16 right now).
4281           */
4282           char *zUtf8 = winConvertToUtf8Filename(zConverted);
4283           if( !zUtf8 ){
4284             sqlite3_free(zConverted);
4285             sqlite3_free(zBuf);
4286             OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4287             return SQLITE_IOERR_NOMEM;
4288           }
4289           sqlite3_snprintf(nMax, zBuf, "%s", zUtf8);
4290           sqlite3_free(zUtf8);
4291           sqlite3_free(zConverted);
4292           break;
4293         }
4294         sqlite3_free(zConverted);
4295       }
4296     }
4297   }
4298 #elif !SQLITE_OS_WINRT && !defined(__CYGWIN__)
4299   else if( osIsNT() ){
4300     char *zMulti;
4301     LPWSTR zWidePath = sqlite3MallocZero( nMax*sizeof(WCHAR) );
4302     if( !zWidePath ){
4303       sqlite3_free(zBuf);
4304       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4305       return SQLITE_IOERR_NOMEM;
4306     }
4307     if( osGetTempPathW(nMax, zWidePath)==0 ){
4308       sqlite3_free(zWidePath);
4309       sqlite3_free(zBuf);
4310       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
4311       return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
4312                          "winGetTempname2", 0);
4313     }
4314     zMulti = winUnicodeToUtf8(zWidePath);
4315     if( zMulti ){
4316       sqlite3_snprintf(nMax, zBuf, "%s", zMulti);
4317       sqlite3_free(zMulti);
4318       sqlite3_free(zWidePath);
4319     }else{
4320       sqlite3_free(zWidePath);
4321       sqlite3_free(zBuf);
4322       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4323       return SQLITE_IOERR_NOMEM;
4324     }
4325   }
4326 #ifdef SQLITE_WIN32_HAS_ANSI
4327   else{
4328     char *zUtf8;
4329     char *zMbcsPath = sqlite3MallocZero( nMax );
4330     if( !zMbcsPath ){
4331       sqlite3_free(zBuf);
4332       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4333       return SQLITE_IOERR_NOMEM;
4334     }
4335     if( osGetTempPathA(nMax, zMbcsPath)==0 ){
4336       sqlite3_free(zBuf);
4337       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
4338       return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
4339                          "winGetTempname3", 0);
4340     }
4341     zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath);
4342     if( zUtf8 ){
4343       sqlite3_snprintf(nMax, zBuf, "%s", zUtf8);
4344       sqlite3_free(zUtf8);
4345     }else{
4346       sqlite3_free(zBuf);
4347       OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
4348       return SQLITE_IOERR_NOMEM;
4349     }
4350   }
4351 #endif /* SQLITE_WIN32_HAS_ANSI */
4352 #endif /* !SQLITE_OS_WINRT */
4353 
4354   /*
4355   ** Check to make sure the temporary directory ends with an appropriate
4356   ** separator.  If it does not and there is not enough space left to add
4357   ** one, fail.
4358   */
4359   if( !winMakeEndInDirSep(nDir+1, zBuf) ){
4360     sqlite3_free(zBuf);
4361     OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4362     return winLogError(SQLITE_ERROR, 0, "winGetTempname4", 0);
4363   }
4364 
4365   /*
4366   ** Check that the output buffer is large enough for the temporary file
4367   ** name in the following format:
4368   **
4369   **   "<temporary_directory>/etilqs_XXXXXXXXXXXXXXX\0\0"
4370   **
4371   ** If not, return SQLITE_ERROR.  The number 17 is used here in order to
4372   ** account for the space used by the 15 character random suffix and the
4373   ** two trailing NUL characters.  The final directory separator character
4374   ** has already added if it was not already present.
4375   */
4376   nLen = sqlite3Strlen30(zBuf);
4377   if( (nLen + nPre + 17) > nBuf ){
4378     sqlite3_free(zBuf);
4379     OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
4380     return winLogError(SQLITE_ERROR, 0, "winGetTempname5", 0);
4381   }
4382 
4383   sqlite3_snprintf(nBuf-16-nLen, zBuf+nLen, SQLITE_TEMP_FILE_PREFIX);
4384 
4385   j = sqlite3Strlen30(zBuf);
4386   sqlite3_randomness(15, &zBuf[j]);
4387   for(i=0; i<15; i++, j++){
4388     zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
4389   }
4390   zBuf[j] = 0;
4391   zBuf[j+1] = 0;
4392   *pzBuf = zBuf;
4393 
4394   OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
4395   return SQLITE_OK;
4396 }
4397 
4398 /*
4399 ** Return TRUE if the named file is really a directory.  Return false if
4400 ** it is something other than a directory, or if there is any kind of memory
4401 ** allocation failure.
4402 */
4403 static int winIsDir(const void *zConverted){
4404   DWORD attr;
4405   int rc = 0;
4406   DWORD lastErrno;
4407 
4408   if( osIsNT() ){
4409     int cnt = 0;
4410     WIN32_FILE_ATTRIBUTE_DATA sAttrData;
4411     memset(&sAttrData, 0, sizeof(sAttrData));
4412     while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
4413                              GetFileExInfoStandard,
4414                              &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
4415     if( !rc ){
4416       return 0; /* Invalid name? */
4417     }
4418     attr = sAttrData.dwFileAttributes;
4419 #if SQLITE_OS_WINCE==0
4420   }else{
4421     attr = osGetFileAttributesA((char*)zConverted);
4422 #endif
4423   }
4424   return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
4425 }
4426 
4427 /*
4428 ** Open a file.
4429 */
4430 static int winOpen(
4431   sqlite3_vfs *pVfs,        /* Used to get maximum path name length */
4432   const char *zName,        /* Name of the file (UTF-8) */
4433   sqlite3_file *id,         /* Write the SQLite file handle here */
4434   int flags,                /* Open mode flags */
4435   int *pOutFlags            /* Status return flags */
4436 ){
4437   HANDLE h;
4438   DWORD lastErrno = 0;
4439   DWORD dwDesiredAccess;
4440   DWORD dwShareMode;
4441   DWORD dwCreationDisposition;
4442   DWORD dwFlagsAndAttributes = 0;
4443 #if SQLITE_OS_WINCE
4444   int isTemp = 0;
4445 #endif
4446   winFile *pFile = (winFile*)id;
4447   void *zConverted;              /* Filename in OS encoding */
4448   const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
4449   int cnt = 0;
4450 
4451   /* If argument zPath is a NULL pointer, this function is required to open
4452   ** a temporary file. Use this buffer to store the file name in.
4453   */
4454   char *zTmpname = 0; /* For temporary filename, if necessary. */
4455 
4456   int rc = SQLITE_OK;            /* Function Return Code */
4457 #if !defined(NDEBUG) || SQLITE_OS_WINCE
4458   int eType = flags&0xFFFFFF00;  /* Type of file to open */
4459 #endif
4460 
4461   int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
4462   int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
4463   int isCreate     = (flags & SQLITE_OPEN_CREATE);
4464   int isReadonly   = (flags & SQLITE_OPEN_READONLY);
4465   int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
4466 
4467 #ifndef NDEBUG
4468   int isOpenJournal = (isCreate && (
4469         eType==SQLITE_OPEN_MASTER_JOURNAL
4470      || eType==SQLITE_OPEN_MAIN_JOURNAL
4471      || eType==SQLITE_OPEN_WAL
4472   ));
4473 #endif
4474 
4475   OSTRACE(("OPEN name=%s, pFile=%p, flags=%x, pOutFlags=%p\n",
4476            zUtf8Name, id, flags, pOutFlags));
4477 
4478   /* Check the following statements are true:
4479   **
4480   **   (a) Exactly one of the READWRITE and READONLY flags must be set, and
4481   **   (b) if CREATE is set, then READWRITE must also be set, and
4482   **   (c) if EXCLUSIVE is set, then CREATE must also be set.
4483   **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
4484   */
4485   assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
4486   assert(isCreate==0 || isReadWrite);
4487   assert(isExclusive==0 || isCreate);
4488   assert(isDelete==0 || isCreate);
4489 
4490   /* The main DB, main journal, WAL file and master journal are never
4491   ** automatically deleted. Nor are they ever temporary files.  */
4492   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
4493   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
4494   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
4495   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
4496 
4497   /* Assert that the upper layer has set one of the "file-type" flags. */
4498   assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB
4499        || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL
4500        || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL
4501        || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
4502   );
4503 
4504   assert( pFile!=0 );
4505   memset(pFile, 0, sizeof(winFile));
4506   pFile->h = INVALID_HANDLE_VALUE;
4507 
4508 #if SQLITE_OS_WINRT
4509   if( !zUtf8Name && !sqlite3_temp_directory ){
4510     sqlite3_log(SQLITE_ERROR,
4511         "sqlite3_temp_directory variable should be set for WinRT");
4512   }
4513 #endif
4514 
4515   /* If the second argument to this function is NULL, generate a
4516   ** temporary file name to use
4517   */
4518   if( !zUtf8Name ){
4519     assert( isDelete && !isOpenJournal );
4520     rc = winGetTempname(pVfs, &zTmpname);
4521     if( rc!=SQLITE_OK ){
4522       OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
4523       return rc;
4524     }
4525     zUtf8Name = zTmpname;
4526   }
4527 
4528   /* Database filenames are double-zero terminated if they are not
4529   ** URIs with parameters.  Hence, they can always be passed into
4530   ** sqlite3_uri_parameter().
4531   */
4532   assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
4533        zUtf8Name[sqlite3Strlen30(zUtf8Name)+1]==0 );
4534 
4535   /* Convert the filename to the system encoding. */
4536   zConverted = winConvertFromUtf8Filename(zUtf8Name);
4537   if( zConverted==0 ){
4538     sqlite3_free(zTmpname);
4539     OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
4540     return SQLITE_IOERR_NOMEM;
4541   }
4542 
4543   if( winIsDir(zConverted) ){
4544     sqlite3_free(zConverted);
4545     sqlite3_free(zTmpname);
4546     OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
4547     return SQLITE_CANTOPEN_ISDIR;
4548   }
4549 
4550   if( isReadWrite ){
4551     dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
4552   }else{
4553     dwDesiredAccess = GENERIC_READ;
4554   }
4555 
4556   /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is
4557   ** created. SQLite doesn't use it to indicate "exclusive access"
4558   ** as it is usually understood.
4559   */
4560   if( isExclusive ){
4561     /* Creates a new file, only if it does not already exist. */
4562     /* If the file exists, it fails. */
4563     dwCreationDisposition = CREATE_NEW;
4564   }else if( isCreate ){
4565     /* Open existing file, or create if it doesn't exist */
4566     dwCreationDisposition = OPEN_ALWAYS;
4567   }else{
4568     /* Opens a file, only if it exists. */
4569     dwCreationDisposition = OPEN_EXISTING;
4570   }
4571 
4572   dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
4573 
4574   if( isDelete ){
4575 #if SQLITE_OS_WINCE
4576     dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
4577     isTemp = 1;
4578 #else
4579     dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
4580                                | FILE_ATTRIBUTE_HIDDEN
4581                                | FILE_FLAG_DELETE_ON_CLOSE;
4582 #endif
4583   }else{
4584     dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
4585   }
4586   /* Reports from the internet are that performance is always
4587   ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
4588 #if SQLITE_OS_WINCE
4589   dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
4590 #endif
4591 
4592   if( osIsNT() ){
4593 #if SQLITE_OS_WINRT
4594     CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
4595     extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
4596     extendedParameters.dwFileAttributes =
4597             dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
4598     extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
4599     extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
4600     extendedParameters.lpSecurityAttributes = NULL;
4601     extendedParameters.hTemplateFile = NULL;
4602     while( (h = osCreateFile2((LPCWSTR)zConverted,
4603                               dwDesiredAccess,
4604                               dwShareMode,
4605                               dwCreationDisposition,
4606                               &extendedParameters))==INVALID_HANDLE_VALUE &&
4607                               winRetryIoerr(&cnt, &lastErrno) ){
4608                /* Noop */
4609     }
4610 #else
4611     while( (h = osCreateFileW((LPCWSTR)zConverted,
4612                               dwDesiredAccess,
4613                               dwShareMode, NULL,
4614                               dwCreationDisposition,
4615                               dwFlagsAndAttributes,
4616                               NULL))==INVALID_HANDLE_VALUE &&
4617                               winRetryIoerr(&cnt, &lastErrno) ){
4618                /* Noop */
4619     }
4620 #endif
4621   }
4622 #ifdef SQLITE_WIN32_HAS_ANSI
4623   else{
4624     while( (h = osCreateFileA((LPCSTR)zConverted,
4625                               dwDesiredAccess,
4626                               dwShareMode, NULL,
4627                               dwCreationDisposition,
4628                               dwFlagsAndAttributes,
4629                               NULL))==INVALID_HANDLE_VALUE &&
4630                               winRetryIoerr(&cnt, &lastErrno) ){
4631                /* Noop */
4632     }
4633   }
4634 #endif
4635   winLogIoerr(cnt);
4636 
4637   OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
4638            dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
4639 
4640   if( h==INVALID_HANDLE_VALUE ){
4641     pFile->lastErrno = lastErrno;
4642     winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
4643     sqlite3_free(zConverted);
4644     sqlite3_free(zTmpname);
4645     if( isReadWrite && !isExclusive ){
4646       return winOpen(pVfs, zName, id,
4647          ((flags|SQLITE_OPEN_READONLY) &
4648                      ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
4649          pOutFlags);
4650     }else{
4651       return SQLITE_CANTOPEN_BKPT;
4652     }
4653   }
4654 
4655   if( pOutFlags ){
4656     if( isReadWrite ){
4657       *pOutFlags = SQLITE_OPEN_READWRITE;
4658     }else{
4659       *pOutFlags = SQLITE_OPEN_READONLY;
4660     }
4661   }
4662 
4663   OSTRACE(("OPEN file=%p, name=%s, access=%lx, pOutFlags=%p, *pOutFlags=%d, "
4664            "rc=%s\n", h, zUtf8Name, dwDesiredAccess, pOutFlags, pOutFlags ?
4665            *pOutFlags : 0, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
4666 
4667 #if SQLITE_OS_WINCE
4668   if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
4669        && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
4670   ){
4671     osCloseHandle(h);
4672     sqlite3_free(zConverted);
4673     sqlite3_free(zTmpname);
4674     OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
4675     return rc;
4676   }
4677   if( isTemp ){
4678     pFile->zDeleteOnClose = zConverted;
4679   }else
4680 #endif
4681   {
4682     sqlite3_free(zConverted);
4683   }
4684 
4685   sqlite3_free(zTmpname);
4686   pFile->pMethod = &winIoMethod;
4687   pFile->pVfs = pVfs;
4688   pFile->h = h;
4689   if( isReadonly ){
4690     pFile->ctrlFlags |= WINFILE_RDONLY;
4691   }
4692   if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
4693     pFile->ctrlFlags |= WINFILE_PSOW;
4694   }
4695   pFile->lastErrno = NO_ERROR;
4696   pFile->zPath = zName;
4697 #if SQLITE_MAX_MMAP_SIZE>0
4698   pFile->hMap = NULL;
4699   pFile->pMapRegion = 0;
4700   pFile->mmapSize = 0;
4701   pFile->mmapSizeActual = 0;
4702   pFile->mmapSizeMax = sqlite3GlobalConfig.szMmap;
4703 #endif
4704 
4705   OpenCounter(+1);
4706   return rc;
4707 }
4708 
4709 /*
4710 ** Delete the named file.
4711 **
4712 ** Note that Windows does not allow a file to be deleted if some other
4713 ** process has it open.  Sometimes a virus scanner or indexing program
4714 ** will open a journal file shortly after it is created in order to do
4715 ** whatever it does.  While this other process is holding the
4716 ** file open, we will be unable to delete it.  To work around this
4717 ** problem, we delay 100 milliseconds and try to delete again.  Up
4718 ** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
4719 ** up and returning an error.
4720 */
4721 static int winDelete(
4722   sqlite3_vfs *pVfs,          /* Not used on win32 */
4723   const char *zFilename,      /* Name of file to delete */
4724   int syncDir                 /* Not used on win32 */
4725 ){
4726   int cnt = 0;
4727   int rc;
4728   DWORD attr;
4729   DWORD lastErrno = 0;
4730   void *zConverted;
4731   UNUSED_PARAMETER(pVfs);
4732   UNUSED_PARAMETER(syncDir);
4733 
4734   SimulateIOError(return SQLITE_IOERR_DELETE);
4735   OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));
4736 
4737   zConverted = winConvertFromUtf8Filename(zFilename);
4738   if( zConverted==0 ){
4739     OSTRACE(("DELETE name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
4740     return SQLITE_IOERR_NOMEM;
4741   }
4742   if( osIsNT() ){
4743     do {
4744 #if SQLITE_OS_WINRT
4745       WIN32_FILE_ATTRIBUTE_DATA sAttrData;
4746       memset(&sAttrData, 0, sizeof(sAttrData));
4747       if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
4748                                   &sAttrData) ){
4749         attr = sAttrData.dwFileAttributes;
4750       }else{
4751         lastErrno = osGetLastError();
4752         if( lastErrno==ERROR_FILE_NOT_FOUND
4753          || lastErrno==ERROR_PATH_NOT_FOUND ){
4754           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
4755         }else{
4756           rc = SQLITE_ERROR;
4757         }
4758         break;
4759       }
4760 #else
4761       attr = osGetFileAttributesW(zConverted);
4762 #endif
4763       if ( attr==INVALID_FILE_ATTRIBUTES ){
4764         lastErrno = osGetLastError();
4765         if( lastErrno==ERROR_FILE_NOT_FOUND
4766          || lastErrno==ERROR_PATH_NOT_FOUND ){
4767           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
4768         }else{
4769           rc = SQLITE_ERROR;
4770         }
4771         break;
4772       }
4773       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
4774         rc = SQLITE_ERROR; /* Files only. */
4775         break;
4776       }
4777       if ( osDeleteFileW(zConverted) ){
4778         rc = SQLITE_OK; /* Deleted OK. */
4779         break;
4780       }
4781       if ( !winRetryIoerr(&cnt, &lastErrno) ){
4782         rc = SQLITE_ERROR; /* No more retries. */
4783         break;
4784       }
4785     } while(1);
4786   }
4787 #ifdef SQLITE_WIN32_HAS_ANSI
4788   else{
4789     do {
4790       attr = osGetFileAttributesA(zConverted);
4791       if ( attr==INVALID_FILE_ATTRIBUTES ){
4792         lastErrno = osGetLastError();
4793         if( lastErrno==ERROR_FILE_NOT_FOUND
4794          || lastErrno==ERROR_PATH_NOT_FOUND ){
4795           rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
4796         }else{
4797           rc = SQLITE_ERROR;
4798         }
4799         break;
4800       }
4801       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
4802         rc = SQLITE_ERROR; /* Files only. */
4803         break;
4804       }
4805       if ( osDeleteFileA(zConverted) ){
4806         rc = SQLITE_OK; /* Deleted OK. */
4807         break;
4808       }
4809       if ( !winRetryIoerr(&cnt, &lastErrno) ){
4810         rc = SQLITE_ERROR; /* No more retries. */
4811         break;
4812       }
4813     } while(1);
4814   }
4815 #endif
4816   if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
4817     rc = winLogError(SQLITE_IOERR_DELETE, lastErrno, "winDelete", zFilename);
4818   }else{
4819     winLogIoerr(cnt);
4820   }
4821   sqlite3_free(zConverted);
4822   OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
4823   return rc;
4824 }
4825 
4826 /*
4827 ** Check the existence and status of a file.
4828 */
4829 static int winAccess(
4830   sqlite3_vfs *pVfs,         /* Not used on win32 */
4831   const char *zFilename,     /* Name of file to check */
4832   int flags,                 /* Type of test to make on this file */
4833   int *pResOut               /* OUT: Result */
4834 ){
4835   DWORD attr;
4836   int rc = 0;
4837   DWORD lastErrno = 0;
4838   void *zConverted;
4839   UNUSED_PARAMETER(pVfs);
4840 
4841   SimulateIOError( return SQLITE_IOERR_ACCESS; );
4842   OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
4843            zFilename, flags, pResOut));
4844 
4845   zConverted = winConvertFromUtf8Filename(zFilename);
4846   if( zConverted==0 ){
4847     OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
4848     return SQLITE_IOERR_NOMEM;
4849   }
4850   if( osIsNT() ){
4851     int cnt = 0;
4852     WIN32_FILE_ATTRIBUTE_DATA sAttrData;
4853     memset(&sAttrData, 0, sizeof(sAttrData));
4854     while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
4855                              GetFileExInfoStandard,
4856                              &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
4857     if( rc ){
4858       /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
4859       ** as if it does not exist.
4860       */
4861       if(    flags==SQLITE_ACCESS_EXISTS
4862           && sAttrData.nFileSizeHigh==0
4863           && sAttrData.nFileSizeLow==0 ){
4864         attr = INVALID_FILE_ATTRIBUTES;
4865       }else{
4866         attr = sAttrData.dwFileAttributes;
4867       }
4868     }else{
4869       winLogIoerr(cnt);
4870       if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
4871         sqlite3_free(zConverted);
4872         return winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess",
4873                            zFilename);
4874       }else{
4875         attr = INVALID_FILE_ATTRIBUTES;
4876       }
4877     }
4878   }
4879 #ifdef SQLITE_WIN32_HAS_ANSI
4880   else{
4881     attr = osGetFileAttributesA((char*)zConverted);
4882   }
4883 #endif
4884   sqlite3_free(zConverted);
4885   switch( flags ){
4886     case SQLITE_ACCESS_READ:
4887     case SQLITE_ACCESS_EXISTS:
4888       rc = attr!=INVALID_FILE_ATTRIBUTES;
4889       break;
4890     case SQLITE_ACCESS_READWRITE:
4891       rc = attr!=INVALID_FILE_ATTRIBUTES &&
4892              (attr & FILE_ATTRIBUTE_READONLY)==0;
4893       break;
4894     default:
4895       assert(!"Invalid flags argument");
4896   }
4897   *pResOut = rc;
4898   OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
4899            zFilename, pResOut, *pResOut));
4900   return SQLITE_OK;
4901 }
4902 
4903 /*
4904 ** Returns non-zero if the specified path name starts with a drive letter
4905 ** followed by a colon character.
4906 */
4907 static BOOL winIsDriveLetterAndColon(
4908   const char *zPathname
4909 ){
4910   return ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' );
4911 }
4912 
4913 /*
4914 ** Returns non-zero if the specified path name should be used verbatim.  If
4915 ** non-zero is returned from this function, the calling function must simply
4916 ** use the provided path name verbatim -OR- resolve it into a full path name
4917 ** using the GetFullPathName Win32 API function (if available).
4918 */
4919 static BOOL winIsVerbatimPathname(
4920   const char *zPathname
4921 ){
4922   /*
4923   ** If the path name starts with a forward slash or a backslash, it is either
4924   ** a legal UNC name, a volume relative path, or an absolute path name in the
4925   ** "Unix" format on Windows.  There is no easy way to differentiate between
4926   ** the final two cases; therefore, we return the safer return value of TRUE
4927   ** so that callers of this function will simply use it verbatim.
4928   */
4929   if ( winIsDirSep(zPathname[0]) ){
4930     return TRUE;
4931   }
4932 
4933   /*
4934   ** If the path name starts with a letter and a colon it is either a volume
4935   ** relative path or an absolute path.  Callers of this function must not
4936   ** attempt to treat it as a relative path name (i.e. they should simply use
4937   ** it verbatim).
4938   */
4939   if ( winIsDriveLetterAndColon(zPathname) ){
4940     return TRUE;
4941   }
4942 
4943   /*
4944   ** If we get to this point, the path name should almost certainly be a purely
4945   ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
4946   */
4947   return FALSE;
4948 }
4949 
4950 /*
4951 ** Turn a relative pathname into a full pathname.  Write the full
4952 ** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
4953 ** bytes in size.
4954 */
4955 static int winFullPathname(
4956   sqlite3_vfs *pVfs,            /* Pointer to vfs object */
4957   const char *zRelative,        /* Possibly relative input path */
4958   int nFull,                    /* Size of output buffer in bytes */
4959   char *zFull                   /* Output buffer */
4960 ){
4961 
4962 #if defined(__CYGWIN__)
4963   SimulateIOError( return SQLITE_ERROR );
4964   UNUSED_PARAMETER(nFull);
4965   assert( nFull>=pVfs->mxPathname );
4966   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
4967     /*
4968     ** NOTE: We are dealing with a relative path name and the data
4969     **       directory has been set.  Therefore, use it as the basis
4970     **       for converting the relative path name to an absolute
4971     **       one by prepending the data directory and a slash.
4972     */
4973     char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
4974     if( !zOut ){
4975       return SQLITE_IOERR_NOMEM;
4976     }
4977     if( cygwin_conv_path(
4978             (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A) |
4979             CCP_RELATIVE, zRelative, zOut, pVfs->mxPathname+1)<0 ){
4980       sqlite3_free(zOut);
4981       return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
4982                          "winFullPathname1", zRelative);
4983     }else{
4984       char *zUtf8 = winConvertToUtf8Filename(zOut);
4985       if( !zUtf8 ){
4986         sqlite3_free(zOut);
4987         return SQLITE_IOERR_NOMEM;
4988       }
4989       sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
4990                        sqlite3_data_directory, winGetDirSep(), zUtf8);
4991       sqlite3_free(zUtf8);
4992       sqlite3_free(zOut);
4993     }
4994   }else{
4995     char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
4996     if( !zOut ){
4997       return SQLITE_IOERR_NOMEM;
4998     }
4999     if( cygwin_conv_path(
5000             (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A),
5001             zRelative, zOut, pVfs->mxPathname+1)<0 ){
5002       sqlite3_free(zOut);
5003       return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
5004                          "winFullPathname2", zRelative);
5005     }else{
5006       char *zUtf8 = winConvertToUtf8Filename(zOut);
5007       if( !zUtf8 ){
5008         sqlite3_free(zOut);
5009         return SQLITE_IOERR_NOMEM;
5010       }
5011       sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zUtf8);
5012       sqlite3_free(zUtf8);
5013       sqlite3_free(zOut);
5014     }
5015   }
5016   return SQLITE_OK;
5017 #endif
5018 
5019 #if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
5020   SimulateIOError( return SQLITE_ERROR );
5021   /* WinCE has no concept of a relative pathname, or so I am told. */
5022   /* WinRT has no way to convert a relative path to an absolute one. */
5023   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5024     /*
5025     ** NOTE: We are dealing with a relative path name and the data
5026     **       directory has been set.  Therefore, use it as the basis
5027     **       for converting the relative path name to an absolute
5028     **       one by prepending the data directory and a backslash.
5029     */
5030     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5031                      sqlite3_data_directory, winGetDirSep(), zRelative);
5032   }else{
5033     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
5034   }
5035   return SQLITE_OK;
5036 #endif
5037 
5038 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
5039   DWORD nByte;
5040   void *zConverted;
5041   char *zOut;
5042 
5043   /* If this path name begins with "/X:", where "X" is any alphabetic
5044   ** character, discard the initial "/" from the pathname.
5045   */
5046   if( zRelative[0]=='/' && winIsDriveLetterAndColon(zRelative+1) ){
5047     zRelative++;
5048   }
5049 
5050   /* It's odd to simulate an io-error here, but really this is just
5051   ** using the io-error infrastructure to test that SQLite handles this
5052   ** function failing. This function could fail if, for example, the
5053   ** current working directory has been unlinked.
5054   */
5055   SimulateIOError( return SQLITE_ERROR );
5056   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
5057     /*
5058     ** NOTE: We are dealing with a relative path name and the data
5059     **       directory has been set.  Therefore, use it as the basis
5060     **       for converting the relative path name to an absolute
5061     **       one by prepending the data directory and a backslash.
5062     */
5063     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
5064                      sqlite3_data_directory, winGetDirSep(), zRelative);
5065     return SQLITE_OK;
5066   }
5067   zConverted = winConvertFromUtf8Filename(zRelative);
5068   if( zConverted==0 ){
5069     return SQLITE_IOERR_NOMEM;
5070   }
5071   if( osIsNT() ){
5072     LPWSTR zTemp;
5073     nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
5074     if( nByte==0 ){
5075       sqlite3_free(zConverted);
5076       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5077                          "winFullPathname1", zRelative);
5078     }
5079     nByte += 3;
5080     zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
5081     if( zTemp==0 ){
5082       sqlite3_free(zConverted);
5083       return SQLITE_IOERR_NOMEM;
5084     }
5085     nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
5086     if( nByte==0 ){
5087       sqlite3_free(zConverted);
5088       sqlite3_free(zTemp);
5089       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5090                          "winFullPathname2", zRelative);
5091     }
5092     sqlite3_free(zConverted);
5093     zOut = winUnicodeToUtf8(zTemp);
5094     sqlite3_free(zTemp);
5095   }
5096 #ifdef SQLITE_WIN32_HAS_ANSI
5097   else{
5098     char *zTemp;
5099     nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
5100     if( nByte==0 ){
5101       sqlite3_free(zConverted);
5102       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5103                          "winFullPathname3", zRelative);
5104     }
5105     nByte += 3;
5106     zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
5107     if( zTemp==0 ){
5108       sqlite3_free(zConverted);
5109       return SQLITE_IOERR_NOMEM;
5110     }
5111     nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
5112     if( nByte==0 ){
5113       sqlite3_free(zConverted);
5114       sqlite3_free(zTemp);
5115       return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
5116                          "winFullPathname4", zRelative);
5117     }
5118     sqlite3_free(zConverted);
5119     zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
5120     sqlite3_free(zTemp);
5121   }
5122 #endif
5123   if( zOut ){
5124     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zOut);
5125     sqlite3_free(zOut);
5126     return SQLITE_OK;
5127   }else{
5128     return SQLITE_IOERR_NOMEM;
5129   }
5130 #endif
5131 }
5132 
5133 #ifndef SQLITE_OMIT_LOAD_EXTENSION
5134 /*
5135 ** Interfaces for opening a shared library, finding entry points
5136 ** within the shared library, and closing the shared library.
5137 */
5138 /*
5139 ** Interfaces for opening a shared library, finding entry points
5140 ** within the shared library, and closing the shared library.
5141 */
5142 static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
5143   HANDLE h;
5144   void *zConverted = winConvertFromUtf8Filename(zFilename);
5145   UNUSED_PARAMETER(pVfs);
5146   if( zConverted==0 ){
5147     return 0;
5148   }
5149   if( osIsNT() ){
5150 #if SQLITE_OS_WINRT
5151     h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
5152 #else
5153     h = osLoadLibraryW((LPCWSTR)zConverted);
5154 #endif
5155   }
5156 #ifdef SQLITE_WIN32_HAS_ANSI
5157   else{
5158     h = osLoadLibraryA((char*)zConverted);
5159   }
5160 #endif
5161   sqlite3_free(zConverted);
5162   return (void*)h;
5163 }
5164 static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
5165   UNUSED_PARAMETER(pVfs);
5166   winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
5167 }
5168 static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
5169   UNUSED_PARAMETER(pVfs);
5170   return (void(*)(void))osGetProcAddressA((HANDLE)pH, zSym);
5171 }
5172 static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
5173   UNUSED_PARAMETER(pVfs);
5174   osFreeLibrary((HANDLE)pHandle);
5175 }
5176 #else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
5177   #define winDlOpen  0
5178   #define winDlError 0
5179   #define winDlSym   0
5180   #define winDlClose 0
5181 #endif
5182 
5183 
5184 /*
5185 ** Write up to nBuf bytes of randomness into zBuf.
5186 */
5187 static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5188   int n = 0;
5189   UNUSED_PARAMETER(pVfs);
5190 #if defined(SQLITE_TEST)
5191   n = nBuf;
5192   memset(zBuf, 0, nBuf);
5193 #else
5194   if( sizeof(SYSTEMTIME)<=nBuf-n ){
5195     SYSTEMTIME x;
5196     osGetSystemTime(&x);
5197     memcpy(&zBuf[n], &x, sizeof(x));
5198     n += sizeof(x);
5199   }
5200   if( sizeof(DWORD)<=nBuf-n ){
5201     DWORD pid = osGetCurrentProcessId();
5202     memcpy(&zBuf[n], &pid, sizeof(pid));
5203     n += sizeof(pid);
5204   }
5205 #if SQLITE_OS_WINRT
5206   if( sizeof(ULONGLONG)<=nBuf-n ){
5207     ULONGLONG cnt = osGetTickCount64();
5208     memcpy(&zBuf[n], &cnt, sizeof(cnt));
5209     n += sizeof(cnt);
5210   }
5211 #else
5212   if( sizeof(DWORD)<=nBuf-n ){
5213     DWORD cnt = osGetTickCount();
5214     memcpy(&zBuf[n], &cnt, sizeof(cnt));
5215     n += sizeof(cnt);
5216   }
5217 #endif
5218   if( sizeof(LARGE_INTEGER)<=nBuf-n ){
5219     LARGE_INTEGER i;
5220     osQueryPerformanceCounter(&i);
5221     memcpy(&zBuf[n], &i, sizeof(i));
5222     n += sizeof(i);
5223   }
5224 #endif
5225   return n;
5226 }
5227 
5228 
5229 /*
5230 ** Sleep for a little while.  Return the amount of time slept.
5231 */
5232 static int winSleep(sqlite3_vfs *pVfs, int microsec){
5233   sqlite3_win32_sleep((microsec+999)/1000);
5234   UNUSED_PARAMETER(pVfs);
5235   return ((microsec+999)/1000)*1000;
5236 }
5237 
5238 /*
5239 ** The following variable, if set to a non-zero value, is interpreted as
5240 ** the number of seconds since 1970 and is used to set the result of
5241 ** sqlite3OsCurrentTime() during testing.
5242 */
5243 #ifdef SQLITE_TEST
5244 int sqlite3_current_time = 0;  /* Fake system time in seconds since 1970. */
5245 #endif
5246 
5247 /*
5248 ** Find the current time (in Universal Coordinated Time).  Write into *piNow
5249 ** the current time and date as a Julian Day number times 86_400_000.  In
5250 ** other words, write into *piNow the number of milliseconds since the Julian
5251 ** epoch of noon in Greenwich on November 24, 4714 B.C according to the
5252 ** proleptic Gregorian calendar.
5253 **
5254 ** On success, return SQLITE_OK.  Return SQLITE_ERROR if the time and date
5255 ** cannot be found.
5256 */
5257 static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
5258   /* FILETIME structure is a 64-bit value representing the number of
5259      100-nanosecond intervals since January 1, 1601 (= JD 2305813.5).
5260   */
5261   FILETIME ft;
5262   static const sqlite3_int64 winFiletimeEpoch = 23058135*(sqlite3_int64)8640000;
5263 #ifdef SQLITE_TEST
5264   static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
5265 #endif
5266   /* 2^32 - to avoid use of LL and warnings in gcc */
5267   static const sqlite3_int64 max32BitValue =
5268       (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 +
5269       (sqlite3_int64)294967296;
5270 
5271 #if SQLITE_OS_WINCE
5272   SYSTEMTIME time;
5273   osGetSystemTime(&time);
5274   /* if SystemTimeToFileTime() fails, it returns zero. */
5275   if (!osSystemTimeToFileTime(&time,&ft)){
5276     return SQLITE_ERROR;
5277   }
5278 #else
5279   osGetSystemTimeAsFileTime( &ft );
5280 #endif
5281 
5282   *piNow = winFiletimeEpoch +
5283             ((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) +
5284                (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000;
5285 
5286 #ifdef SQLITE_TEST
5287   if( sqlite3_current_time ){
5288     *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
5289   }
5290 #endif
5291   UNUSED_PARAMETER(pVfs);
5292   return SQLITE_OK;
5293 }
5294 
5295 /*
5296 ** Find the current time (in Universal Coordinated Time).  Write the
5297 ** current time and date as a Julian Day number into *prNow and
5298 ** return 0.  Return 1 if the time and date cannot be found.
5299 */
5300 static int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
5301   int rc;
5302   sqlite3_int64 i;
5303   rc = winCurrentTimeInt64(pVfs, &i);
5304   if( !rc ){
5305     *prNow = i/86400000.0;
5306   }
5307   return rc;
5308 }
5309 
5310 /*
5311 ** The idea is that this function works like a combination of
5312 ** GetLastError() and FormatMessage() on Windows (or errno and
5313 ** strerror_r() on Unix). After an error is returned by an OS
5314 ** function, SQLite calls this function with zBuf pointing to
5315 ** a buffer of nBuf bytes. The OS layer should populate the
5316 ** buffer with a nul-terminated UTF-8 encoded error message
5317 ** describing the last IO error to have occurred within the calling
5318 ** thread.
5319 **
5320 ** If the error message is too large for the supplied buffer,
5321 ** it should be truncated. The return value of xGetLastError
5322 ** is zero if the error message fits in the buffer, or non-zero
5323 ** otherwise (if the message was truncated). If non-zero is returned,
5324 ** then it is not necessary to include the nul-terminator character
5325 ** in the output buffer.
5326 **
5327 ** Not supplying an error message will have no adverse effect
5328 ** on SQLite. It is fine to have an implementation that never
5329 ** returns an error message:
5330 **
5331 **   int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5332 **     assert(zBuf[0]=='\0');
5333 **     return 0;
5334 **   }
5335 **
5336 ** However if an error message is supplied, it will be incorporated
5337 ** by sqlite into the error message available to the user using
5338 ** sqlite3_errmsg(), possibly making IO errors easier to debug.
5339 */
5340 static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
5341   UNUSED_PARAMETER(pVfs);
5342   return winGetLastErrorMsg(osGetLastError(), nBuf, zBuf);
5343 }
5344 
5345 /*
5346 ** Initialize and deinitialize the operating system interface.
5347 */
5348 int sqlite3_os_init(void){
5349   static sqlite3_vfs winVfs = {
5350     3,                   /* iVersion */
5351     sizeof(winFile),     /* szOsFile */
5352     SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
5353     0,                   /* pNext */
5354     "win32",             /* zName */
5355     0,                   /* pAppData */
5356     winOpen,             /* xOpen */
5357     winDelete,           /* xDelete */
5358     winAccess,           /* xAccess */
5359     winFullPathname,     /* xFullPathname */
5360     winDlOpen,           /* xDlOpen */
5361     winDlError,          /* xDlError */
5362     winDlSym,            /* xDlSym */
5363     winDlClose,          /* xDlClose */
5364     winRandomness,       /* xRandomness */
5365     winSleep,            /* xSleep */
5366     winCurrentTime,      /* xCurrentTime */
5367     winGetLastError,     /* xGetLastError */
5368     winCurrentTimeInt64, /* xCurrentTimeInt64 */
5369     winSetSystemCall,    /* xSetSystemCall */
5370     winGetSystemCall,    /* xGetSystemCall */
5371     winNextSystemCall,   /* xNextSystemCall */
5372   };
5373 #if defined(SQLITE_WIN32_HAS_WIDE)
5374   static sqlite3_vfs winLongPathVfs = {
5375     3,                   /* iVersion */
5376     sizeof(winFile),     /* szOsFile */
5377     SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
5378     0,                   /* pNext */
5379     "win32-longpath",    /* zName */
5380     0,                   /* pAppData */
5381     winOpen,             /* xOpen */
5382     winDelete,           /* xDelete */
5383     winAccess,           /* xAccess */
5384     winFullPathname,     /* xFullPathname */
5385     winDlOpen,           /* xDlOpen */
5386     winDlError,          /* xDlError */
5387     winDlSym,            /* xDlSym */
5388     winDlClose,          /* xDlClose */
5389     winRandomness,       /* xRandomness */
5390     winSleep,            /* xSleep */
5391     winCurrentTime,      /* xCurrentTime */
5392     winGetLastError,     /* xGetLastError */
5393     winCurrentTimeInt64, /* xCurrentTimeInt64 */
5394     winSetSystemCall,    /* xSetSystemCall */
5395     winGetSystemCall,    /* xGetSystemCall */
5396     winNextSystemCall,   /* xNextSystemCall */
5397   };
5398 #endif
5399 
5400   /* Double-check that the aSyscall[] array has been constructed
5401   ** correctly.  See ticket [bb3a86e890c8e96ab] */
5402   assert( ArraySize(aSyscall)==76 );
5403 
5404   /* get memory map allocation granularity */
5405   memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
5406 #if SQLITE_OS_WINRT
5407   osGetNativeSystemInfo(&winSysInfo);
5408 #else
5409   osGetSystemInfo(&winSysInfo);
5410 #endif
5411   assert( winSysInfo.dwAllocationGranularity>0 );
5412   assert( winSysInfo.dwPageSize>0 );
5413 
5414   sqlite3_vfs_register(&winVfs, 1);
5415 
5416 #if defined(SQLITE_WIN32_HAS_WIDE)
5417   sqlite3_vfs_register(&winLongPathVfs, 0);
5418 #endif
5419 
5420   return SQLITE_OK;
5421 }
5422 
5423 int sqlite3_os_end(void){
5424 #if SQLITE_OS_WINRT
5425   if( sleepObj!=NULL ){
5426     osCloseHandle(sleepObj);
5427     sleepObj = NULL;
5428   }
5429 #endif
5430   return SQLITE_OK;
5431 }
5432 
5433 #endif /* SQLITE_OS_WIN */
5434