680 lines
21 KiB
C
680 lines
21 KiB
C
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/*
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** 2010 April 7
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**
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** The author disclaims copyright to this source code. In place of
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** a legal notice, here is a blessing:
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**
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** May you do good and not evil.
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** May you find forgiveness for yourself and forgive others.
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** May you share freely, never taking more than you give.
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**
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*************************************************************************
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**
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** This file implements an example of a simple VFS implementation that
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** omits complex features often not required or not possible on embedded
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** platforms. Code is included to buffer writes to the journal file,
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** which can be a significant performance improvement on some embedded
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** platforms.
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**
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** OVERVIEW
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**
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** The code in this file implements a minimal SQLite VFS that can be
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** used on Linux and other posix-like operating systems. The following
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** system calls are used:
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**
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** File-system: access(), unlink(), getcwd()
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** File IO: open(), read(), write(), fsync(), close(), fstat()
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** Other: sleep(), usleep(), time()
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**
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** The following VFS features are omitted:
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**
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** 1. File locking. The user must ensure that there is at most one
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** connection to each database when using this VFS. Multiple
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** connections to a single shared-cache count as a single connection
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** for the purposes of the previous statement.
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**
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** 2. The loading of dynamic extensions (shared libraries).
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**
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** 3. Temporary files. The user must configure SQLite to use in-memory
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** temp files when using this VFS. The easiest way to do this is to
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** compile with:
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**
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** -DSQLITE_TEMP_STORE=3
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**
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** 4. File truncation. As of version 3.6.24, SQLite may run without
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** a working xTruncate() call, providing the user does not configure
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** SQLite to use "journal_mode=truncate", or use both
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** "journal_mode=persist" and ATTACHed databases.
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**
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** It is assumed that the system uses UNIX-like path-names. Specifically,
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** that '/' characters are used to separate path components and that
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** a path-name is a relative path unless it begins with a '/'. And that
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** no UTF-8 encoded paths are greater than 512 bytes in length.
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**
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** JOURNAL WRITE-BUFFERING
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**
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** To commit a transaction to the database, SQLite first writes rollback
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** information into the journal file. This usually consists of 4 steps:
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**
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** 1. The rollback information is sequentially written into the journal
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** file, starting at the start of the file.
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** 2. The journal file is synced to disk.
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** 3. A modification is made to the first few bytes of the journal file.
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** 4. The journal file is synced to disk again.
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**
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** Most of the data is written in step 1 using a series of calls to the
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** VFS xWrite() method. The buffers passed to the xWrite() calls are of
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** various sizes. For example, as of version 3.6.24, when committing a
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** transaction that modifies 3 pages of a database file that uses 4096
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** byte pages residing on a media with 512 byte sectors, SQLite makes
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** eleven calls to the xWrite() method to create the rollback journal,
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** as follows:
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**
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** Write offset | Bytes written
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** ----------------------------
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** 0 512
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** 512 4
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** 516 4096
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** 4612 4
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** 4616 4
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** 4620 4096
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** 8716 4
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** 8720 4
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** 8724 4096
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** 12820 4
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** ++++++++++++SYNC+++++++++++
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** 0 12
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** ++++++++++++SYNC+++++++++++
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**
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** On many operating systems, this is an efficient way to write to a file.
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** However, on some embedded systems that do not cache writes in OS
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** buffers it is much more efficient to write data in blocks that are
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** an integer multiple of the sector-size in size and aligned at the
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** start of a sector.
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**
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** To work around this, the code in this file allocates a fixed size
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** buffer of SQLITE_DEMOVFS_BUFFERSZ using sqlite3_malloc() whenever a
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** journal file is opened. It uses the buffer to coalesce sequential
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** writes into aligned SQLITE_DEMOVFS_BUFFERSZ blocks. When SQLite
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** invokes the xSync() method to sync the contents of the file to disk,
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** all accumulated data is written out, even if it does not constitute
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** a complete block. This means the actual IO to create the rollback
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** journal for the example transaction above is this:
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**
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** Write offset | Bytes written
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** ----------------------------
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** 0 8192
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** 8192 4632
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** ++++++++++++SYNC+++++++++++
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** 0 12
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** ++++++++++++SYNC+++++++++++
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**
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** Much more efficient if the underlying OS is not caching write
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** operations.
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*/
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#if !defined(SQLITE_TEST) || SQLITE_OS_UNIX
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#include <sqlite3.h>
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#include <assert.h>
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#include <string.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <sys/file.h>
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#include <sys/param.h>
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#include <unistd.h>
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#include <time.h>
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#include <errno.h>
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#include <fcntl.h>
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/*
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** Size of the write buffer used by journal files in bytes.
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*/
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#ifndef SQLITE_DEMOVFS_BUFFERSZ
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# define SQLITE_DEMOVFS_BUFFERSZ 8192
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#endif
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/*
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** The maximum pathname length supported by this VFS.
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*/
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#define MAXPATHNAME 512
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/*
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** When using this VFS, the sqlite3_file* handles that SQLite uses are
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** actually pointers to instances of type DemoFile.
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*/
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typedef struct DemoFile DemoFile;
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struct DemoFile {
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sqlite3_file base; /* Base class. Must be first. */
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int fd; /* File descriptor */
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char *aBuffer; /* Pointer to malloc'd buffer */
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int nBuffer; /* Valid bytes of data in zBuffer */
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sqlite3_int64 iBufferOfst; /* Offset in file of zBuffer[0] */
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};
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/*
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** Write directly to the file passed as the first argument. Even if the
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** file has a write-buffer (DemoFile.aBuffer), ignore it.
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*/
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static int demoDirectWrite(
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DemoFile *p, /* File handle */
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const void *zBuf, /* Buffer containing data to write */
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int iAmt, /* Size of data to write in bytes */
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sqlite_int64 iOfst /* File offset to write to */
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){
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off_t ofst; /* Return value from lseek() */
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size_t nWrite; /* Return value from write() */
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ofst = lseek(p->fd, iOfst, SEEK_SET);
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if( ofst!=iOfst ){
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return SQLITE_IOERR_WRITE;
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}
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nWrite = write(p->fd, zBuf, iAmt);
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if( nWrite!=iAmt ){
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return SQLITE_IOERR_WRITE;
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}
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return SQLITE_OK;
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}
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/*
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** Flush the contents of the DemoFile.aBuffer buffer to disk. This is a
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** no-op if this particular file does not have a buffer (i.e. it is not
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** a journal file) or if the buffer is currently empty.
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*/
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static int demoFlushBuffer(DemoFile *p){
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int rc = SQLITE_OK;
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if( p->nBuffer ){
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rc = demoDirectWrite(p, p->aBuffer, p->nBuffer, p->iBufferOfst);
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p->nBuffer = 0;
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}
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return rc;
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}
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/*
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** Close a file.
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*/
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static int demoClose(sqlite3_file *pFile){
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int rc;
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DemoFile *p = (DemoFile*)pFile;
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rc = demoFlushBuffer(p);
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sqlite3_free(p->aBuffer);
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close(p->fd);
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return rc;
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}
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/*
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** Read data from a file.
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*/
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static int demoRead(
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sqlite3_file *pFile,
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void *zBuf,
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int iAmt,
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sqlite_int64 iOfst
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){
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DemoFile *p = (DemoFile*)pFile;
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off_t ofst; /* Return value from lseek() */
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int nRead; /* Return value from read() */
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int rc; /* Return code from demoFlushBuffer() */
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/* Flush any data in the write buffer to disk in case this operation
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** is trying to read data the file-region currently cached in the buffer.
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** It would be possible to detect this case and possibly save an
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** unnecessary write here, but in practice SQLite will rarely read from
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** a journal file when there is data cached in the write-buffer.
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*/
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rc = demoFlushBuffer(p);
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if( rc!=SQLITE_OK ){
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return rc;
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}
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ofst = lseek(p->fd, iOfst, SEEK_SET);
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if( ofst!=iOfst ){
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return SQLITE_IOERR_READ;
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}
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nRead = read(p->fd, zBuf, iAmt);
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if( nRead==iAmt ){
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return SQLITE_OK;
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}else if( nRead>=0 ){
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return SQLITE_IOERR_SHORT_READ;
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}
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return SQLITE_IOERR_READ;
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}
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/*
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** Write data to a crash-file.
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*/
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static int demoWrite(
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sqlite3_file *pFile,
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const void *zBuf,
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int iAmt,
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sqlite_int64 iOfst
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){
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DemoFile *p = (DemoFile*)pFile;
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if( p->aBuffer ){
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char *z = (char *)zBuf; /* Pointer to remaining data to write */
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int n = iAmt; /* Number of bytes at z */
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sqlite3_int64 i = iOfst; /* File offset to write to */
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while( n>0 ){
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int nCopy; /* Number of bytes to copy into buffer */
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/* If the buffer is full, or if this data is not being written directly
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** following the data already buffered, flush the buffer. Flushing
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** the buffer is a no-op if it is empty.
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*/
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if( p->nBuffer==SQLITE_DEMOVFS_BUFFERSZ || p->iBufferOfst+p->nBuffer!=i ){
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int rc = demoFlushBuffer(p);
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if( rc!=SQLITE_OK ){
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return rc;
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}
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}
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assert( p->nBuffer==0 || p->iBufferOfst+p->nBuffer==i );
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p->iBufferOfst = i - p->nBuffer;
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/* Copy as much data as possible into the buffer. */
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nCopy = SQLITE_DEMOVFS_BUFFERSZ - p->nBuffer;
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if( nCopy>n ){
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nCopy = n;
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}
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memcpy(&p->aBuffer[p->nBuffer], z, nCopy);
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p->nBuffer += nCopy;
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n -= nCopy;
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i += nCopy;
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z += nCopy;
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}
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}else{
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return demoDirectWrite(p, zBuf, iAmt, iOfst);
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}
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return SQLITE_OK;
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}
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/*
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** Truncate a file. This is a no-op for this VFS (see header comments at
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** the top of the file).
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*/
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static int demoTruncate(sqlite3_file *pFile, sqlite_int64 size){
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#if 0
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if( ftruncate(((DemoFile *)pFile)->fd, size) ) return SQLITE_IOERR_TRUNCATE;
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#endif
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return SQLITE_OK;
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}
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/*
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** Sync the contents of the file to the persistent media.
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*/
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static int demoSync(sqlite3_file *pFile, int flags){
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DemoFile *p = (DemoFile*)pFile;
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int rc;
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rc = demoFlushBuffer(p);
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if( rc!=SQLITE_OK ){
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return rc;
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}
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rc = fsync(p->fd);
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return (rc==0 ? SQLITE_OK : SQLITE_IOERR_FSYNC);
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}
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/*
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** Write the size of the file in bytes to *pSize.
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*/
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static int demoFileSize(sqlite3_file *pFile, sqlite_int64 *pSize){
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DemoFile *p = (DemoFile*)pFile;
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int rc; /* Return code from fstat() call */
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struct stat sStat; /* Output of fstat() call */
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/* Flush the contents of the buffer to disk. As with the flush in the
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** demoRead() method, it would be possible to avoid this and save a write
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** here and there. But in practice this comes up so infrequently it is
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** not worth the trouble.
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*/
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rc = demoFlushBuffer(p);
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if( rc!=SQLITE_OK ){
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return rc;
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}
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rc = fstat(p->fd, &sStat);
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if( rc!=0 ) return SQLITE_IOERR_FSTAT;
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*pSize = sStat.st_size;
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return SQLITE_OK;
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}
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/*
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** Locking functions. The xLock() and xUnlock() methods are both no-ops.
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** The xCheckReservedLock() always indicates that no other process holds
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** a reserved lock on the database file. This ensures that if a hot-journal
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** file is found in the file-system it is rolled back.
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*/
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static int demoLock(sqlite3_file *pFile, int eLock){
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return SQLITE_OK;
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}
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static int demoUnlock(sqlite3_file *pFile, int eLock){
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return SQLITE_OK;
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}
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static int demoCheckReservedLock(sqlite3_file *pFile, int *pResOut){
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*pResOut = 0;
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return SQLITE_OK;
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}
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/*
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** No xFileControl() verbs are implemented by this VFS.
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*/
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static int demoFileControl(sqlite3_file *pFile, int op, void *pArg){
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return SQLITE_OK;
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}
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/*
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** The xSectorSize() and xDeviceCharacteristics() methods. These two
|
||
|
|
** may return special values allowing SQLite to optimize file-system
|
||
|
|
** access to some extent. But it is also safe to simply return 0.
|
||
|
|
*/
|
||
|
|
static int demoSectorSize(sqlite3_file *pFile){
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
static int demoDeviceCharacteristics(sqlite3_file *pFile){
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Open a file handle.
|
||
|
|
*/
|
||
|
|
static int demoOpen(
|
||
|
|
sqlite3_vfs *pVfs, /* VFS */
|
||
|
|
const char *zName, /* File to open, or 0 for a temp file */
|
||
|
|
sqlite3_file *pFile, /* Pointer to DemoFile struct to populate */
|
||
|
|
int flags, /* Input SQLITE_OPEN_XXX flags */
|
||
|
|
int *pOutFlags /* Output SQLITE_OPEN_XXX flags (or NULL) */
|
||
|
|
){
|
||
|
|
static const sqlite3_io_methods demoio = {
|
||
|
|
1, /* iVersion */
|
||
|
|
demoClose, /* xClose */
|
||
|
|
demoRead, /* xRead */
|
||
|
|
demoWrite, /* xWrite */
|
||
|
|
demoTruncate, /* xTruncate */
|
||
|
|
demoSync, /* xSync */
|
||
|
|
demoFileSize, /* xFileSize */
|
||
|
|
demoLock, /* xLock */
|
||
|
|
demoUnlock, /* xUnlock */
|
||
|
|
demoCheckReservedLock, /* xCheckReservedLock */
|
||
|
|
demoFileControl, /* xFileControl */
|
||
|
|
demoSectorSize, /* xSectorSize */
|
||
|
|
demoDeviceCharacteristics /* xDeviceCharacteristics */
|
||
|
|
};
|
||
|
|
|
||
|
|
DemoFile *p = (DemoFile*)pFile; /* Populate this structure */
|
||
|
|
int oflags = 0; /* flags to pass to open() call */
|
||
|
|
char *aBuf = 0;
|
||
|
|
|
||
|
|
if( zName==0 ){
|
||
|
|
return SQLITE_IOERR;
|
||
|
|
}
|
||
|
|
|
||
|
|
if( flags&SQLITE_OPEN_MAIN_JOURNAL ){
|
||
|
|
aBuf = (char *)sqlite3_malloc(SQLITE_DEMOVFS_BUFFERSZ);
|
||
|
|
if( !aBuf ){
|
||
|
|
return SQLITE_NOMEM;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if( flags&SQLITE_OPEN_EXCLUSIVE ) oflags |= O_EXCL;
|
||
|
|
if( flags&SQLITE_OPEN_CREATE ) oflags |= O_CREAT;
|
||
|
|
if( flags&SQLITE_OPEN_READONLY ) oflags |= O_RDONLY;
|
||
|
|
if( flags&SQLITE_OPEN_READWRITE ) oflags |= O_RDWR;
|
||
|
|
|
||
|
|
memset(p, 0, sizeof(DemoFile));
|
||
|
|
p->fd = open(zName, oflags, 0600);
|
||
|
|
if( p->fd<0 ){
|
||
|
|
sqlite3_free(aBuf);
|
||
|
|
return SQLITE_CANTOPEN;
|
||
|
|
}
|
||
|
|
p->aBuffer = aBuf;
|
||
|
|
|
||
|
|
if( pOutFlags ){
|
||
|
|
*pOutFlags = flags;
|
||
|
|
}
|
||
|
|
p->base.pMethods = &demoio;
|
||
|
|
return SQLITE_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Delete the file identified by argument zPath. If the dirSync parameter
|
||
|
|
** is non-zero, then ensure the file-system modification to delete the
|
||
|
|
** file has been synced to disk before returning.
|
||
|
|
*/
|
||
|
|
static int demoDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
|
||
|
|
int rc; /* Return code */
|
||
|
|
|
||
|
|
rc = unlink(zPath);
|
||
|
|
if( rc!=0 && errno==ENOENT ) return SQLITE_OK;
|
||
|
|
|
||
|
|
if( rc==0 && dirSync ){
|
||
|
|
int dfd; /* File descriptor open on directory */
|
||
|
|
int i; /* Iterator variable */
|
||
|
|
char zDir[MAXPATHNAME+1]; /* Name of directory containing file zPath */
|
||
|
|
|
||
|
|
/* Figure out the directory name from the path of the file deleted. */
|
||
|
|
sqlite3_snprintf(MAXPATHNAME, zDir, "%s", zPath);
|
||
|
|
zDir[MAXPATHNAME] = '\0';
|
||
|
|
for(i=strlen(zDir); i>1 && zDir[i]!='/'; i++);
|
||
|
|
zDir[i] = '\0';
|
||
|
|
|
||
|
|
/* Open a file-descriptor on the directory. Sync. Close. */
|
||
|
|
dfd = open(zDir, O_RDONLY, 0);
|
||
|
|
if( dfd<0 ){
|
||
|
|
rc = -1;
|
||
|
|
}else{
|
||
|
|
rc = fsync(dfd);
|
||
|
|
close(dfd);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return (rc==0 ? SQLITE_OK : SQLITE_IOERR_DELETE);
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifndef F_OK
|
||
|
|
# define F_OK 0
|
||
|
|
#endif
|
||
|
|
#ifndef R_OK
|
||
|
|
# define R_OK 4
|
||
|
|
#endif
|
||
|
|
#ifndef W_OK
|
||
|
|
# define W_OK 2
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Query the file-system to see if the named file exists, is readable or
|
||
|
|
** is both readable and writable.
|
||
|
|
*/
|
||
|
|
static int demoAccess(
|
||
|
|
sqlite3_vfs *pVfs,
|
||
|
|
const char *zPath,
|
||
|
|
int flags,
|
||
|
|
int *pResOut
|
||
|
|
){
|
||
|
|
int rc; /* access() return code */
|
||
|
|
int eAccess = F_OK; /* Second argument to access() */
|
||
|
|
|
||
|
|
assert( flags==SQLITE_ACCESS_EXISTS /* access(zPath, F_OK) */
|
||
|
|
|| flags==SQLITE_ACCESS_READ /* access(zPath, R_OK) */
|
||
|
|
|| flags==SQLITE_ACCESS_READWRITE /* access(zPath, R_OK|W_OK) */
|
||
|
|
);
|
||
|
|
|
||
|
|
if( flags==SQLITE_ACCESS_READWRITE ) eAccess = R_OK|W_OK;
|
||
|
|
if( flags==SQLITE_ACCESS_READ ) eAccess = R_OK;
|
||
|
|
|
||
|
|
rc = access(zPath, eAccess);
|
||
|
|
*pResOut = (rc==0);
|
||
|
|
return SQLITE_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Argument zPath points to a nul-terminated string containing a file path.
|
||
|
|
** If zPath is an absolute path, then it is copied as is into the output
|
||
|
|
** buffer. Otherwise, if it is a relative path, then the equivalent full
|
||
|
|
** path is written to the output buffer.
|
||
|
|
**
|
||
|
|
** This function assumes that paths are UNIX style. Specifically, that:
|
||
|
|
**
|
||
|
|
** 1. Path components are separated by a '/'. and
|
||
|
|
** 2. Full paths begin with a '/' character.
|
||
|
|
*/
|
||
|
|
static int demoFullPathname(
|
||
|
|
sqlite3_vfs *pVfs, /* VFS */
|
||
|
|
const char *zPath, /* Input path (possibly a relative path) */
|
||
|
|
int nPathOut, /* Size of output buffer in bytes */
|
||
|
|
char *zPathOut /* Pointer to output buffer */
|
||
|
|
){
|
||
|
|
char zDir[MAXPATHNAME+1];
|
||
|
|
if( zPath[0]=='/' ){
|
||
|
|
zDir[0] = '\0';
|
||
|
|
}else{
|
||
|
|
if( getcwd(zDir, sizeof(zDir))==0 ) return SQLITE_IOERR;
|
||
|
|
}
|
||
|
|
zDir[MAXPATHNAME] = '\0';
|
||
|
|
|
||
|
|
sqlite3_snprintf(nPathOut, zPathOut, "%s/%s", zDir, zPath);
|
||
|
|
zPathOut[nPathOut-1] = '\0';
|
||
|
|
|
||
|
|
return SQLITE_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** The following four VFS methods:
|
||
|
|
**
|
||
|
|
** xDlOpen
|
||
|
|
** xDlError
|
||
|
|
** xDlSym
|
||
|
|
** xDlClose
|
||
|
|
**
|
||
|
|
** are supposed to implement the functionality needed by SQLite to load
|
||
|
|
** extensions compiled as shared objects. This simple VFS does not support
|
||
|
|
** this functionality, so the following functions are no-ops.
|
||
|
|
*/
|
||
|
|
static void *demoDlOpen(sqlite3_vfs *pVfs, const char *zPath){
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
static void demoDlError(sqlite3_vfs *pVfs, int nByte, char *zErrMsg){
|
||
|
|
sqlite3_snprintf(nByte, zErrMsg, "Loadable extensions are not supported");
|
||
|
|
zErrMsg[nByte-1] = '\0';
|
||
|
|
}
|
||
|
|
static void (*demoDlSym(sqlite3_vfs *pVfs, void *pH, const char *z))(void){
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
static void demoDlClose(sqlite3_vfs *pVfs, void *pHandle){
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Parameter zByte points to a buffer nByte bytes in size. Populate this
|
||
|
|
** buffer with pseudo-random data.
|
||
|
|
*/
|
||
|
|
static int demoRandomness(sqlite3_vfs *pVfs, int nByte, char *zByte){
|
||
|
|
return SQLITE_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Sleep for at least nMicro microseconds. Return the (approximate) number
|
||
|
|
** of microseconds slept for.
|
||
|
|
*/
|
||
|
|
static int demoSleep(sqlite3_vfs *pVfs, int nMicro){
|
||
|
|
sleep(nMicro / 1000000);
|
||
|
|
usleep(nMicro % 1000000);
|
||
|
|
return nMicro;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Set *pTime to the current UTC time expressed as a Julian day. Return
|
||
|
|
** SQLITE_OK if successful, or an error code otherwise.
|
||
|
|
**
|
||
|
|
** http://en.wikipedia.org/wiki/Julian_day
|
||
|
|
**
|
||
|
|
** This implementation is not very good. The current time is rounded to
|
||
|
|
** an integer number of seconds. Also, assuming time_t is a signed 32-bit
|
||
|
|
** value, it will stop working some time in the year 2038 AD (the so-called
|
||
|
|
** "year 2038" problem that afflicts systems that store time this way).
|
||
|
|
*/
|
||
|
|
static int demoCurrentTime(sqlite3_vfs *pVfs, double *pTime){
|
||
|
|
time_t t = time(0);
|
||
|
|
*pTime = t/86400.0 + 2440587.5;
|
||
|
|
return SQLITE_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** This function returns a pointer to the VFS implemented in this file.
|
||
|
|
** To make the VFS available to SQLite:
|
||
|
|
**
|
||
|
|
** sqlite3_vfs_register(sqlite3_demovfs(), 0);
|
||
|
|
*/
|
||
|
|
sqlite3_vfs *sqlite3_demovfs(void){
|
||
|
|
static sqlite3_vfs demovfs = {
|
||
|
|
1, /* iVersion */
|
||
|
|
sizeof(DemoFile), /* szOsFile */
|
||
|
|
MAXPATHNAME, /* mxPathname */
|
||
|
|
0, /* pNext */
|
||
|
|
"demo", /* zName */
|
||
|
|
0, /* pAppData */
|
||
|
|
demoOpen, /* xOpen */
|
||
|
|
demoDelete, /* xDelete */
|
||
|
|
demoAccess, /* xAccess */
|
||
|
|
demoFullPathname, /* xFullPathname */
|
||
|
|
demoDlOpen, /* xDlOpen */
|
||
|
|
demoDlError, /* xDlError */
|
||
|
|
demoDlSym, /* xDlSym */
|
||
|
|
demoDlClose, /* xDlClose */
|
||
|
|
demoRandomness, /* xRandomness */
|
||
|
|
demoSleep, /* xSleep */
|
||
|
|
demoCurrentTime, /* xCurrentTime */
|
||
|
|
};
|
||
|
|
return &demovfs;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* !defined(SQLITE_TEST) || SQLITE_OS_UNIX */
|
||
|
|
|
||
|
|
|
||
|
|
#ifdef SQLITE_TEST
|
||
|
|
|
||
|
|
#include <tcl.h>
|
||
|
|
|
||
|
|
#if SQLITE_OS_UNIX
|
||
|
|
static int register_demovfs(
|
||
|
|
ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
|
||
|
|
Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
|
||
|
|
int objc, /* Number of arguments */
|
||
|
|
Tcl_Obj *CONST objv[] /* Command arguments */
|
||
|
|
){
|
||
|
|
sqlite3_vfs_register(sqlite3_demovfs(), 1);
|
||
|
|
return TCL_OK;
|
||
|
|
}
|
||
|
|
static int unregister_demovfs(
|
||
|
|
ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
|
||
|
|
Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
|
||
|
|
int objc, /* Number of arguments */
|
||
|
|
Tcl_Obj *CONST objv[] /* Command arguments */
|
||
|
|
){
|
||
|
|
sqlite3_vfs_unregister(sqlite3_demovfs());
|
||
|
|
return TCL_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Register commands with the TCL interpreter.
|
||
|
|
*/
|
||
|
|
int Sqlitetest_demovfs_Init(Tcl_Interp *interp){
|
||
|
|
Tcl_CreateObjCommand(interp, "register_demovfs", register_demovfs, 0, 0);
|
||
|
|
Tcl_CreateObjCommand(interp, "unregister_demovfs", unregister_demovfs, 0, 0);
|
||
|
|
return TCL_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
#else
|
||
|
|
int Sqlitetest_demovfs_Init(Tcl_Interp *interp){ return TCL_OK; }
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#endif /* SQLITE_TEST */
|