1.1 --- a/extensions/sqlite/sqlite-source/os.h Fri Jul 11 06:51:21 2008 +0000
1.2 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000
1.3 @@ -1,284 +0,0 @@
1.4 -/*
1.5 -** 2001 September 16
1.6 -**
1.7 -** The author disclaims copyright to this source code. In place of
1.8 -** a legal notice, here is a blessing:
1.9 -**
1.10 -** May you do good and not evil.
1.11 -** May you find forgiveness for yourself and forgive others.
1.12 -** May you share freely, never taking more than you give.
1.13 -**
1.14 -******************************************************************************
1.15 -**
1.16 -** This header file (together with is companion C source-code file
1.17 -** "os.c") attempt to abstract the underlying operating system so that
1.18 -** the SQLite library will work on both POSIX and windows systems.
1.19 -**
1.20 -** This header file is #include-ed by sqliteInt.h and thus ends up
1.21 -** being included by every source file.
1.22 -*/
1.23 -#ifndef _SQLITE_OS_H_
1.24 -#define _SQLITE_OS_H_
1.25 -
1.26 -/*
1.27 -** Figure out if we are dealing with Unix, Windows, or some other
1.28 -** operating system. After the following block of preprocess macros,
1.29 -** all of OS_UNIX, OS_WIN, OS_OS2, and OS_OTHER will defined to either
1.30 -** 1 or 0. One of the four will be 1. The other three will be 0.
1.31 -*/
1.32 -#if defined(OS_OTHER)
1.33 -# if OS_OTHER==1
1.34 -# undef OS_UNIX
1.35 -# define OS_UNIX 0
1.36 -# undef OS_WIN
1.37 -# define OS_WIN 0
1.38 -# undef OS_OS2
1.39 -# define OS_OS2 0
1.40 -# else
1.41 -# undef OS_OTHER
1.42 -# endif
1.43 -#endif
1.44 -#if !defined(OS_UNIX) && !defined(OS_OTHER)
1.45 -# define OS_OTHER 0
1.46 -# ifndef OS_WIN
1.47 -# if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
1.48 -# define OS_WIN 1
1.49 -# define OS_UNIX 0
1.50 -# define OS_OS2 0
1.51 -# elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__)
1.52 -# define OS_WIN 0
1.53 -# define OS_UNIX 0
1.54 -# define OS_OS2 1
1.55 -# else
1.56 -# define OS_WIN 0
1.57 -# define OS_UNIX 1
1.58 -# define OS_OS2 0
1.59 -# endif
1.60 -# else
1.61 -# define OS_UNIX 0
1.62 -# define OS_OS2 0
1.63 -# endif
1.64 -#else
1.65 -# ifndef OS_WIN
1.66 -# define OS_WIN 0
1.67 -# endif
1.68 -#endif
1.69 -
1.70 -
1.71 -
1.72 -/*
1.73 -** Define the maximum size of a temporary filename
1.74 -*/
1.75 -#if OS_WIN
1.76 -# include <windows.h>
1.77 -# define SQLITE_TEMPNAME_SIZE (MAX_PATH+50)
1.78 -#elif OS_OS2
1.79 -# if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY)
1.80 -# include <os2safe.h> /* has to be included before os2.h for linking to work */
1.81 -# endif
1.82 -# define INCL_DOSDATETIME
1.83 -# define INCL_DOSFILEMGR
1.84 -# define INCL_DOSERRORS
1.85 -# define INCL_DOSMISC
1.86 -# define INCL_DOSPROCESS
1.87 -# define INCL_DOSMODULEMGR
1.88 -# include <os2.h>
1.89 -# define SQLITE_TEMPNAME_SIZE (CCHMAXPATHCOMP)
1.90 -#else
1.91 -# define SQLITE_TEMPNAME_SIZE 200
1.92 -#endif
1.93 -
1.94 -/* If the SET_FULLSYNC macro is not defined above, then make it
1.95 -** a no-op
1.96 -*/
1.97 -#ifndef SET_FULLSYNC
1.98 -# define SET_FULLSYNC(x,y)
1.99 -#endif
1.100 -
1.101 -/*
1.102 -** The default size of a disk sector
1.103 -*/
1.104 -#ifndef SQLITE_DEFAULT_SECTOR_SIZE
1.105 -# define SQLITE_DEFAULT_SECTOR_SIZE 512
1.106 -#endif
1.107 -
1.108 -/*
1.109 -** Temporary files are named starting with this prefix followed by 16 random
1.110 -** alphanumeric characters, and no file extension. They are stored in the
1.111 -** OS's standard temporary file directory, and are deleted prior to exit.
1.112 -** If sqlite is being embedded in another program, you may wish to change the
1.113 -** prefix to reflect your program's name, so that if your program exits
1.114 -** prematurely, old temporary files can be easily identified. This can be done
1.115 -** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
1.116 -**
1.117 -** 2006-10-31: The default prefix used to be "sqlite_". But then
1.118 -** Mcafee started using SQLite in their anti-virus product and it
1.119 -** started putting files with the "sqlite" name in the c:/temp folder.
1.120 -** This annoyed many windows users. Those users would then do a
1.121 -** Google search for "sqlite", find the telephone numbers of the
1.122 -** developers and call to wake them up at night and complain.
1.123 -** For this reason, the default name prefix is changed to be "sqlite"
1.124 -** spelled backwards. So the temp files are still identified, but
1.125 -** anybody smart enough to figure out the code is also likely smart
1.126 -** enough to know that calling the developer will not help get rid
1.127 -** of the file.
1.128 -*/
1.129 -#ifndef SQLITE_TEMP_FILE_PREFIX
1.130 -# define SQLITE_TEMP_FILE_PREFIX "etilqs_"
1.131 -#endif
1.132 -
1.133 -/*
1.134 -** If using an alternative OS interface, then we must have an "os_other.h"
1.135 -** header file available for that interface. Presumably the "os_other.h"
1.136 -** header file contains #defines similar to those above.
1.137 -*/
1.138 -#if OS_OTHER
1.139 -# include "os_other.h"
1.140 -#endif
1.141 -
1.142 -
1.143 -/*
1.144 -** The following values may be passed as the second argument to
1.145 -** sqlite3OsLock(). The various locks exhibit the following semantics:
1.146 -**
1.147 -** SHARED: Any number of processes may hold a SHARED lock simultaneously.
1.148 -** RESERVED: A single process may hold a RESERVED lock on a file at
1.149 -** any time. Other processes may hold and obtain new SHARED locks.
1.150 -** PENDING: A single process may hold a PENDING lock on a file at
1.151 -** any one time. Existing SHARED locks may persist, but no new
1.152 -** SHARED locks may be obtained by other processes.
1.153 -** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks.
1.154 -**
1.155 -** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a
1.156 -** process that requests an EXCLUSIVE lock may actually obtain a PENDING
1.157 -** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to
1.158 -** sqlite3OsLock().
1.159 -*/
1.160 -#define NO_LOCK 0
1.161 -#define SHARED_LOCK 1
1.162 -#define RESERVED_LOCK 2
1.163 -#define PENDING_LOCK 3
1.164 -#define EXCLUSIVE_LOCK 4
1.165 -
1.166 -/*
1.167 -** File Locking Notes: (Mostly about windows but also some info for Unix)
1.168 -**
1.169 -** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
1.170 -** those functions are not available. So we use only LockFile() and
1.171 -** UnlockFile().
1.172 -**
1.173 -** LockFile() prevents not just writing but also reading by other processes.
1.174 -** A SHARED_LOCK is obtained by locking a single randomly-chosen
1.175 -** byte out of a specific range of bytes. The lock byte is obtained at
1.176 -** random so two separate readers can probably access the file at the
1.177 -** same time, unless they are unlucky and choose the same lock byte.
1.178 -** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range.
1.179 -** There can only be one writer. A RESERVED_LOCK is obtained by locking
1.180 -** a single byte of the file that is designated as the reserved lock byte.
1.181 -** A PENDING_LOCK is obtained by locking a designated byte different from
1.182 -** the RESERVED_LOCK byte.
1.183 -**
1.184 -** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
1.185 -** which means we can use reader/writer locks. When reader/writer locks
1.186 -** are used, the lock is placed on the same range of bytes that is used
1.187 -** for probabilistic locking in Win95/98/ME. Hence, the locking scheme
1.188 -** will support two or more Win95 readers or two or more WinNT readers.
1.189 -** But a single Win95 reader will lock out all WinNT readers and a single
1.190 -** WinNT reader will lock out all other Win95 readers.
1.191 -**
1.192 -** The following #defines specify the range of bytes used for locking.
1.193 -** SHARED_SIZE is the number of bytes available in the pool from which
1.194 -** a random byte is selected for a shared lock. The pool of bytes for
1.195 -** shared locks begins at SHARED_FIRST.
1.196 -**
1.197 -** These #defines are available in sqlite_aux.h so that adaptors for
1.198 -** connecting SQLite to other operating systems can use the same byte
1.199 -** ranges for locking. In particular, the same locking strategy and
1.200 -** byte ranges are used for Unix. This leaves open the possiblity of having
1.201 -** clients on win95, winNT, and unix all talking to the same shared file
1.202 -** and all locking correctly. To do so would require that samba (or whatever
1.203 -** tool is being used for file sharing) implements locks correctly between
1.204 -** windows and unix. I'm guessing that isn't likely to happen, but by
1.205 -** using the same locking range we are at least open to the possibility.
1.206 -**
1.207 -** Locking in windows is manditory. For this reason, we cannot store
1.208 -** actual data in the bytes used for locking. The pager never allocates
1.209 -** the pages involved in locking therefore. SHARED_SIZE is selected so
1.210 -** that all locks will fit on a single page even at the minimum page size.
1.211 -** PENDING_BYTE defines the beginning of the locks. By default PENDING_BYTE
1.212 -** is set high so that we don't have to allocate an unused page except
1.213 -** for very large databases. But one should test the page skipping logic
1.214 -** by setting PENDING_BYTE low and running the entire regression suite.
1.215 -**
1.216 -** Changing the value of PENDING_BYTE results in a subtly incompatible
1.217 -** file format. Depending on how it is changed, you might not notice
1.218 -** the incompatibility right away, even running a full regression test.
1.219 -** The default location of PENDING_BYTE is the first byte past the
1.220 -** 1GB boundary.
1.221 -**
1.222 -*/
1.223 -#ifndef SQLITE_TEST
1.224 -#define PENDING_BYTE 0x40000000 /* First byte past the 1GB boundary */
1.225 -#else
1.226 -extern unsigned int sqlite3_pending_byte;
1.227 -#define PENDING_BYTE sqlite3_pending_byte
1.228 -#endif
1.229 -
1.230 -#define RESERVED_BYTE (PENDING_BYTE+1)
1.231 -#define SHARED_FIRST (PENDING_BYTE+2)
1.232 -#define SHARED_SIZE 510
1.233 -
1.234 -/*
1.235 -** Functions for accessing sqlite3_file methods
1.236 -*/
1.237 -int sqlite3OsClose(sqlite3_file*);
1.238 -int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
1.239 -int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
1.240 -int sqlite3OsTruncate(sqlite3_file*, i64 size);
1.241 -int sqlite3OsSync(sqlite3_file*, int);
1.242 -int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
1.243 -int sqlite3OsLock(sqlite3_file*, int);
1.244 -int sqlite3OsUnlock(sqlite3_file*, int);
1.245 -int sqlite3OsCheckReservedLock(sqlite3_file *id);
1.246 -int sqlite3OsFileControl(sqlite3_file*,int,void*);
1.247 -int sqlite3OsSectorSize(sqlite3_file *id);
1.248 -int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
1.249 -
1.250 -/*
1.251 -** Functions for accessing sqlite3_vfs methods
1.252 -*/
1.253 -int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
1.254 -int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
1.255 -int sqlite3OsAccess(sqlite3_vfs *, const char *, int);
1.256 -int sqlite3OsGetTempname(sqlite3_vfs *, int, char *);
1.257 -int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
1.258 -void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
1.259 -void sqlite3OsDlError(sqlite3_vfs *, int, char *);
1.260 -void *sqlite3OsDlSym(sqlite3_vfs *, void *, const char *);
1.261 -void sqlite3OsDlClose(sqlite3_vfs *, void *);
1.262 -int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
1.263 -int sqlite3OsSleep(sqlite3_vfs *, int);
1.264 -int sqlite3OsCurrentTime(sqlite3_vfs *, double*);
1.265 -
1.266 -/*
1.267 -** Convenience functions for opening and closing files using
1.268 -** sqlite3_malloc() to obtain space for the file-handle structure.
1.269 -*/
1.270 -int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
1.271 -int sqlite3OsCloseFree(sqlite3_file *);
1.272 -
1.273 -/*
1.274 -** Each OS-specific backend defines an instance of the following
1.275 -** structure for returning a pointer to its sqlite3_vfs. If OS_OTHER
1.276 -** is defined (meaning that the application-defined OS interface layer
1.277 -** is used) then there is no default VFS. The application must
1.278 -** register one or more VFS structures using sqlite3_vfs_register()
1.279 -** before attempting to use SQLite.
1.280 -*/
1.281 -#if OS_UNIX || OS_WIN || OS_OS2
1.282 -sqlite3_vfs *sqlite3OsDefaultVfs(void);
1.283 -#else
1.284 -# define sqlite3OsDefaultVfs(X) 0
1.285 -#endif
1.286 -
1.287 -#endif /* _SQLITE_OS_H_ */
