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Diffstat (limited to 'third_party/sqlite/os.h')
| -rw-r--r-- | third_party/sqlite/os.h | 548 |
1 files changed, 548 insertions, 0 deletions
diff --git a/third_party/sqlite/os.h b/third_party/sqlite/os.h new file mode 100644 index 0000000..76a9f2c --- /dev/null +++ b/third_party/sqlite/os.h @@ -0,0 +1,548 @@ +/* +** 2001 September 16 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +****************************************************************************** +** +** This header file (together with is companion C source-code file +** "os.c") attempt to abstract the underlying operating system so that +** the SQLite library will work on both POSIX and windows systems. +*/ +#ifndef _SQLITE_OS_H_ +#define _SQLITE_OS_H_ + +/* +** Figure out if we are dealing with Unix, Windows, or some other +** operating system. +*/ +#if defined(OS_OTHER) +# if OS_OTHER==1 +# undef OS_UNIX +# define OS_UNIX 0 +# undef OS_WIN +# define OS_WIN 0 +# undef OS_OS2 +# define OS_OS2 0 +# else +# undef OS_OTHER +# endif +#endif +#if !defined(OS_UNIX) && !defined(OS_OTHER) +# define OS_OTHER 0 +# ifndef OS_WIN +# if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__) +# define OS_WIN 1 +# define OS_UNIX 0 +# define OS_OS2 0 +# elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__) +# define OS_WIN 0 +# define OS_UNIX 0 +# define OS_OS2 1 +# else +# define OS_WIN 0 +# define OS_UNIX 1 +# define OS_OS2 0 +# endif +# else +# define OS_UNIX 0 +# define OS_OS2 0 +# endif +#else +# ifndef OS_WIN +# define OS_WIN 0 +# endif +#endif + + +/* +** Define the maximum size of a temporary filename +*/ +#if OS_WIN +# include <windows.h> +# define SQLITE_TEMPNAME_SIZE (MAX_PATH+50) +#elif OS_OS2 +# if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY) +# include <os2safe.h> /* has to be included before os2.h for linking to work */ +# endif +# define INCL_DOSDATETIME +# define INCL_DOSFILEMGR +# define INCL_DOSERRORS +# define INCL_DOSMISC +# define INCL_DOSPROCESS +# define INCL_DOSMODULEMGR +# include <os2.h> +# define SQLITE_TEMPNAME_SIZE (CCHMAXPATHCOMP) +#else +# define SQLITE_TEMPNAME_SIZE 200 +#endif + +/* If the SET_FULLSYNC macro is not defined above, then make it +** a no-op +*/ +#ifndef SET_FULLSYNC +# define SET_FULLSYNC(x,y) +#endif + +/* +** The default size of a disk sector +*/ +#ifndef SQLITE_DEFAULT_SECTOR_SIZE +# define SQLITE_DEFAULT_SECTOR_SIZE 512 +#endif + +/* +** Temporary files are named starting with this prefix followed by 16 random +** alphanumeric characters, and no file extension. They are stored in the +** OS's standard temporary file directory, and are deleted prior to exit. +** If sqlite is being embedded in another program, you may wish to change the +** prefix to reflect your program's name, so that if your program exits +** prematurely, old temporary files can be easily identified. This can be done +** using -DTEMP_FILE_PREFIX=myprefix_ on the compiler command line. +** +** 2006-10-31: The default prefix used to be "sqlite_". But then +** Mcafee started using SQLite in their anti-virus product and it +** started putting files with the "sqlite" name in the c:/temp folder. +** This annoyed many windows users. Those users would then do a +** Google search for "sqlite", find the telephone numbers of the +** developers and call to wake them up at night and complain. +** For this reason, the default name prefix is changed to be "sqlite" +** spelled backwards. So the temp files are still identified, but +** anybody smart enough to figure out the code is also likely smart +** enough to know that calling the developer will not help get rid +** of the file. +*/ +#ifndef TEMP_FILE_PREFIX +# define TEMP_FILE_PREFIX "etilqs_" +#endif + +/* +** Define the interfaces for Unix, Windows, and OS/2. +*/ +#if OS_UNIX +#define sqlite3OsOpenReadWrite sqlite3UnixOpenReadWrite +#define sqlite3OsOpenExclusive sqlite3UnixOpenExclusive +#define sqlite3OsOpenReadOnly sqlite3UnixOpenReadOnly +#define sqlite3OsDelete sqlite3UnixDelete +#define sqlite3OsFileExists sqlite3UnixFileExists +#define sqlite3OsFullPathname sqlite3UnixFullPathname +#define sqlite3OsIsDirWritable sqlite3UnixIsDirWritable +#define sqlite3OsSyncDirectory sqlite3UnixSyncDirectory +#define sqlite3OsTempFileName sqlite3UnixTempFileName +#define sqlite3OsRandomSeed sqlite3UnixRandomSeed +#define sqlite3OsSleep sqlite3UnixSleep +#define sqlite3OsCurrentTime sqlite3UnixCurrentTime +#define sqlite3OsEnterMutex sqlite3UnixEnterMutex +#define sqlite3OsLeaveMutex sqlite3UnixLeaveMutex +#define sqlite3OsInMutex sqlite3UnixInMutex +#define sqlite3OsThreadSpecificData sqlite3UnixThreadSpecificData +#define sqlite3OsMalloc sqlite3GenericMalloc +#define sqlite3OsRealloc sqlite3GenericRealloc +#define sqlite3OsFree sqlite3GenericFree +#define sqlite3OsAllocationSize sqlite3GenericAllocationSize +#define sqlite3OsDlopen sqlite3UnixDlopen +#define sqlite3OsDlsym sqlite3UnixDlsym +#define sqlite3OsDlclose sqlite3UnixDlclose +#endif +#if OS_WIN +#define sqlite3OsOpenReadWrite sqlite3WinOpenReadWrite +#define sqlite3OsOpenExclusive sqlite3WinOpenExclusive +#define sqlite3OsOpenReadOnly sqlite3WinOpenReadOnly +#define sqlite3OsDelete sqlite3WinDelete +#define sqlite3OsFileExists sqlite3WinFileExists +#define sqlite3OsFullPathname sqlite3WinFullPathname +#define sqlite3OsIsDirWritable sqlite3WinIsDirWritable +#define sqlite3OsSyncDirectory sqlite3WinSyncDirectory +#define sqlite3OsTempFileName sqlite3WinTempFileName +#define sqlite3OsRandomSeed sqlite3WinRandomSeed +#define sqlite3OsSleep sqlite3WinSleep +#define sqlite3OsCurrentTime sqlite3WinCurrentTime +#define sqlite3OsEnterMutex sqlite3WinEnterMutex +#define sqlite3OsLeaveMutex sqlite3WinLeaveMutex +#define sqlite3OsInMutex sqlite3WinInMutex +#define sqlite3OsThreadSpecificData sqlite3WinThreadSpecificData +#define sqlite3OsMalloc sqlite3GenericMalloc +#define sqlite3OsRealloc sqlite3GenericRealloc +#define sqlite3OsFree sqlite3GenericFree +#define sqlite3OsAllocationSize sqlite3GenericAllocationSize +#define sqlite3OsDlopen sqlite3WinDlopen +#define sqlite3OsDlsym sqlite3WinDlsym +#define sqlite3OsDlclose sqlite3WinDlclose +#endif +#if OS_OS2 +#define sqlite3OsOpenReadWrite sqlite3Os2OpenReadWrite +#define sqlite3OsOpenExclusive sqlite3Os2OpenExclusive +#define sqlite3OsOpenReadOnly sqlite3Os2OpenReadOnly +#define sqlite3OsDelete sqlite3Os2Delete +#define sqlite3OsFileExists sqlite3Os2FileExists +#define sqlite3OsFullPathname sqlite3Os2FullPathname +#define sqlite3OsIsDirWritable sqlite3Os2IsDirWritable +#define sqlite3OsSyncDirectory sqlite3Os2SyncDirectory +#define sqlite3OsTempFileName sqlite3Os2TempFileName +#define sqlite3OsRandomSeed sqlite3Os2RandomSeed +#define sqlite3OsSleep sqlite3Os2Sleep +#define sqlite3OsCurrentTime sqlite3Os2CurrentTime +#define sqlite3OsEnterMutex sqlite3Os2EnterMutex +#define sqlite3OsLeaveMutex sqlite3Os2LeaveMutex +#define sqlite3OsInMutex sqlite3Os2InMutex +#define sqlite3OsThreadSpecificData sqlite3Os2ThreadSpecificData +#define sqlite3OsMalloc sqlite3GenericMalloc +#define sqlite3OsRealloc sqlite3GenericRealloc +#define sqlite3OsFree sqlite3GenericFree +#define sqlite3OsAllocationSize sqlite3GenericAllocationSize +#define sqlite3OsDlopen sqlite3Os2Dlopen +#define sqlite3OsDlsym sqlite3Os2Dlsym +#define sqlite3OsDlclose sqlite3Os2Dlclose +#endif + + + + +/* +** If using an alternative OS interface, then we must have an "os_other.h" +** header file available for that interface. Presumably the "os_other.h" +** header file contains #defines similar to those above. +*/ +#if OS_OTHER +# include "os_other.h" +#endif + + + +/* +** Forward declarations +*/ +typedef struct OsFile OsFile; +typedef struct IoMethod IoMethod; + +/* +** An instance of the following structure contains pointers to all +** methods on an OsFile object. +*/ +struct IoMethod { + int (*xClose)(OsFile**); + int (*xOpenDirectory)(OsFile*, const char*); + int (*xRead)(OsFile*, void*, int amt); + int (*xWrite)(OsFile*, const void*, int amt); + int (*xSeek)(OsFile*, i64 offset); + int (*xTruncate)(OsFile*, i64 size); + int (*xSync)(OsFile*, int); + void (*xSetFullSync)(OsFile *id, int setting); + int (*xFileHandle)(OsFile *id); + int (*xFileSize)(OsFile*, i64 *pSize); + int (*xLock)(OsFile*, int); + int (*xUnlock)(OsFile*, int); + int (*xLockState)(OsFile *id); + int (*xCheckReservedLock)(OsFile *id); + int (*xSectorSize)(OsFile *id); +}; + +/* +** The OsFile object describes an open disk file in an OS-dependent way. +** The version of OsFile defined here is a generic version. Each OS +** implementation defines its own subclass of this structure that contains +** additional information needed to handle file I/O. But the pMethod +** entry (pointing to the virtual function table) always occurs first +** so that we can always find the appropriate methods. +*/ +struct OsFile { + IoMethod const *pMethod; +}; + +/* +** The following values may be passed as the second argument to +** sqlite3OsLock(). The various locks exhibit the following semantics: +** +** SHARED: Any number of processes may hold a SHARED lock simultaneously. +** RESERVED: A single process may hold a RESERVED lock on a file at +** any time. Other processes may hold and obtain new SHARED locks. +** PENDING: A single process may hold a PENDING lock on a file at +** any one time. Existing SHARED locks may persist, but no new +** SHARED locks may be obtained by other processes. +** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks. +** +** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a +** process that requests an EXCLUSIVE lock may actually obtain a PENDING +** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to +** sqlite3OsLock(). +*/ +#define NO_LOCK 0 +#define SHARED_LOCK 1 +#define RESERVED_LOCK 2 +#define PENDING_LOCK 3 +#define EXCLUSIVE_LOCK 4 + +/* +** File Locking Notes: (Mostly about windows but also some info for Unix) +** +** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because +** those functions are not available. So we use only LockFile() and +** UnlockFile(). +** +** LockFile() prevents not just writing but also reading by other processes. +** A SHARED_LOCK is obtained by locking a single randomly-chosen +** byte out of a specific range of bytes. The lock byte is obtained at +** random so two separate readers can probably access the file at the +** same time, unless they are unlucky and choose the same lock byte. +** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range. +** There can only be one writer. A RESERVED_LOCK is obtained by locking +** a single byte of the file that is designated as the reserved lock byte. +** A PENDING_LOCK is obtained by locking a designated byte different from +** the RESERVED_LOCK byte. +** +** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available, +** which means we can use reader/writer locks. When reader/writer locks +** are used, the lock is placed on the same range of bytes that is used +** for probabilistic locking in Win95/98/ME. Hence, the locking scheme +** will support two or more Win95 readers or two or more WinNT readers. +** But a single Win95 reader will lock out all WinNT readers and a single +** WinNT reader will lock out all other Win95 readers. +** +** The following #defines specify the range of bytes used for locking. +** SHARED_SIZE is the number of bytes available in the pool from which +** a random byte is selected for a shared lock. The pool of bytes for +** shared locks begins at SHARED_FIRST. +** +** These #defines are available in sqlite_aux.h so that adaptors for +** connecting SQLite to other operating systems can use the same byte +** ranges for locking. In particular, the same locking strategy and +** byte ranges are used for Unix. This leaves open the possiblity of having +** clients on win95, winNT, and unix all talking to the same shared file +** and all locking correctly. To do so would require that samba (or whatever +** tool is being used for file sharing) implements locks correctly between +** windows and unix. I'm guessing that isn't likely to happen, but by +** using the same locking range we are at least open to the possibility. +** +** Locking in windows is manditory. For this reason, we cannot store +** actual data in the bytes used for locking. The pager never allocates +** the pages involved in locking therefore. SHARED_SIZE is selected so +** that all locks will fit on a single page even at the minimum page size. +** PENDING_BYTE defines the beginning of the locks. By default PENDING_BYTE +** is set high so that we don't have to allocate an unused page except +** for very large databases. But one should test the page skipping logic +** by setting PENDING_BYTE low and running the entire regression suite. +** +** Changing the value of PENDING_BYTE results in a subtly incompatible +** file format. Depending on how it is changed, you might not notice +** the incompatibility right away, even running a full regression test. +** The default location of PENDING_BYTE is the first byte past the +** 1GB boundary. +** +*/ +#ifndef SQLITE_TEST +#define PENDING_BYTE 0x40000000 /* First byte past the 1GB boundary */ +#else +extern unsigned int sqlite3_pending_byte; +#define PENDING_BYTE sqlite3_pending_byte +#endif + +#define RESERVED_BYTE (PENDING_BYTE+1) +#define SHARED_FIRST (PENDING_BYTE+2) +#define SHARED_SIZE 510 + +/* +** Prototypes for operating system interface routines. +*/ +int sqlite3OsClose(OsFile**); +int sqlite3OsOpenDirectory(OsFile*, const char*); +int sqlite3OsRead(OsFile*, void*, int amt); +int sqlite3OsWrite(OsFile*, const void*, int amt); +int sqlite3OsSeek(OsFile*, i64 offset); +int sqlite3OsTruncate(OsFile*, i64 size); +int sqlite3OsSync(OsFile*, int); +void sqlite3OsSetFullSync(OsFile *id, int setting); +int sqlite3OsFileSize(OsFile*, i64 *pSize); +int sqlite3OsLock(OsFile*, int); +int sqlite3OsUnlock(OsFile*, int); +int sqlite3OsCheckReservedLock(OsFile *id); +int sqlite3OsOpenReadWrite(const char*, OsFile**, int*); +int sqlite3OsOpenExclusive(const char*, OsFile**, int); +int sqlite3OsOpenReadOnly(const char*, OsFile**); +int sqlite3OsDelete(const char*); +int sqlite3OsFileExists(const char*); +char *sqlite3OsFullPathname(const char*); +int sqlite3OsIsDirWritable(char*); +int sqlite3OsSyncDirectory(const char*); +int sqlite3OsSectorSize(OsFile *id); +int sqlite3OsTempFileName(char*); +int sqlite3OsRandomSeed(char*); +int sqlite3OsSleep(int ms); +int sqlite3OsCurrentTime(double*); +void sqlite3OsEnterMutex(void); +void sqlite3OsLeaveMutex(void); +int sqlite3OsInMutex(int); +ThreadData *sqlite3OsThreadSpecificData(int); +void *sqlite3OsMalloc(int); +void *sqlite3OsRealloc(void *, int); +void sqlite3OsFree(void *); +int sqlite3OsAllocationSize(void *); +void *sqlite3OsDlopen(const char*); +void *sqlite3OsDlsym(void*, const char*); +int sqlite3OsDlclose(void*); + +#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG) + int sqlite3OsFileHandle(OsFile *id); + int sqlite3OsLockState(OsFile *id); +#endif + +/* +** If the SQLITE_ENABLE_REDEF_IO macro is defined, then the OS-layer +** interface routines are not called directly but are invoked using +** pointers to functions. This allows the implementation of various +** OS-layer interface routines to be modified at run-time. There are +** obscure but legitimate reasons for wanting to do this. But for +** most users, a direct call to the underlying interface is preferable +** so the the redefinable I/O interface is turned off by default. +*/ +#ifdef SQLITE_ENABLE_REDEF_IO + +/* +** When redefinable I/O is enabled, a single global instance of the +** following structure holds pointers to the routines that SQLite +** uses to talk with the underlying operating system. Modify this +** structure (before using any SQLite API!) to accomodate perculiar +** operating system interfaces or behaviors. +*/ +struct sqlite3OsVtbl { + int (*xOpenReadWrite)(const char*, OsFile**, int*); + int (*xOpenExclusive)(const char*, OsFile**, int); + int (*xOpenReadOnly)(const char*, OsFile**); + + int (*xDelete)(const char*); + int (*xFileExists)(const char*); + char *(*xFullPathname)(const char*); + int (*xIsDirWritable)(char*); + int (*xSyncDirectory)(const char*); + int (*xTempFileName)(char*); + + int (*xRandomSeed)(char*); + int (*xSleep)(int ms); + int (*xCurrentTime)(double*); + + void (*xEnterMutex)(void); + void (*xLeaveMutex)(void); + int (*xInMutex)(int); + ThreadData *(*xThreadSpecificData)(int); + + void *(*xMalloc)(int); + void *(*xRealloc)(void *, int); + void (*xFree)(void *); + int (*xAllocationSize)(void *); + + void *(*xDlopen)(const char*); + void *(*xDlsym)(void*, const char*); + int (*xDlclose)(void*); +}; + +/* Macro used to comment out routines that do not exists when there is +** no disk I/O or extension loading +*/ +#ifdef SQLITE_OMIT_DISKIO +# define IF_DISKIO(X) 0 +#else +# define IF_DISKIO(X) X +#endif +#ifdef SQLITE_OMIT_LOAD_EXTENSION +# define IF_DLOPEN(X) 0 +#else +# define IF_DLOPEN(X) X +#endif + + +#if defined(_SQLITE_OS_C_) || defined(SQLITE_AMALGAMATION) + /* + ** The os.c file implements the global virtual function table. + ** We have to put this file here because the initializers + ** (ex: sqlite3OsRandomSeed) are macros that are about to be + ** redefined. + */ + struct sqlite3OsVtbl sqlite3Os = { + IF_DISKIO( sqlite3OsOpenReadWrite ), + IF_DISKIO( sqlite3OsOpenExclusive ), + IF_DISKIO( sqlite3OsOpenReadOnly ), + IF_DISKIO( sqlite3OsDelete ), + IF_DISKIO( sqlite3OsFileExists ), + IF_DISKIO( sqlite3OsFullPathname ), + IF_DISKIO( sqlite3OsIsDirWritable ), + IF_DISKIO( sqlite3OsSyncDirectory ), + IF_DISKIO( sqlite3OsTempFileName ), + sqlite3OsRandomSeed, + sqlite3OsSleep, + sqlite3OsCurrentTime, + sqlite3OsEnterMutex, + sqlite3OsLeaveMutex, + sqlite3OsInMutex, + sqlite3OsThreadSpecificData, + sqlite3OsMalloc, + sqlite3OsRealloc, + sqlite3OsFree, + sqlite3OsAllocationSize, + IF_DLOPEN( sqlite3OsDlopen ), + IF_DLOPEN( sqlite3OsDlsym ), + IF_DLOPEN( sqlite3OsDlclose ), + }; +#else + /* + ** Files other than os.c just reference the global virtual function table. + */ + extern struct sqlite3OsVtbl sqlite3Os; +#endif /* _SQLITE_OS_C_ */ + + +/* This additional API routine is available with redefinable I/O */ +struct sqlite3OsVtbl *sqlite3_os_switch(void); + + +/* +** Redefine the OS interface to go through the virtual function table +** rather than calling routines directly. +*/ +#undef sqlite3OsOpenReadWrite +#undef sqlite3OsOpenExclusive +#undef sqlite3OsOpenReadOnly +#undef sqlite3OsDelete +#undef sqlite3OsFileExists +#undef sqlite3OsFullPathname +#undef sqlite3OsIsDirWritable +#undef sqlite3OsSyncDirectory +#undef sqlite3OsTempFileName +#undef sqlite3OsRandomSeed +#undef sqlite3OsSleep +#undef sqlite3OsCurrentTime +#undef sqlite3OsEnterMutex +#undef sqlite3OsLeaveMutex +#undef sqlite3OsInMutex +#undef sqlite3OsThreadSpecificData +#undef sqlite3OsMalloc +#undef sqlite3OsRealloc +#undef sqlite3OsFree +#undef sqlite3OsAllocationSize +#define sqlite3OsOpenReadWrite sqlite3Os.xOpenReadWrite +#define sqlite3OsOpenExclusive sqlite3Os.xOpenExclusive +#define sqlite3OsOpenReadOnly sqlite3Os.xOpenReadOnly +#define sqlite3OsDelete sqlite3Os.xDelete +#define sqlite3OsFileExists sqlite3Os.xFileExists +#define sqlite3OsFullPathname sqlite3Os.xFullPathname +#define sqlite3OsIsDirWritable sqlite3Os.xIsDirWritable +#define sqlite3OsSyncDirectory sqlite3Os.xSyncDirectory +#define sqlite3OsTempFileName sqlite3Os.xTempFileName +#define sqlite3OsRandomSeed sqlite3Os.xRandomSeed +#define sqlite3OsSleep sqlite3Os.xSleep +#define sqlite3OsCurrentTime sqlite3Os.xCurrentTime +#define sqlite3OsEnterMutex sqlite3Os.xEnterMutex +#define sqlite3OsLeaveMutex sqlite3Os.xLeaveMutex +#define sqlite3OsInMutex sqlite3Os.xInMutex +#define sqlite3OsThreadSpecificData sqlite3Os.xThreadSpecificData +#define sqlite3OsMalloc sqlite3Os.xMalloc +#define sqlite3OsRealloc sqlite3Os.xRealloc +#define sqlite3OsFree sqlite3Os.xFree +#define sqlite3OsAllocationSize sqlite3Os.xAllocationSize + +#endif /* SQLITE_ENABLE_REDEF_IO */ + +#endif /* _SQLITE_OS_H_ */ |