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Overview
Comment:Modify the OS layer so that I/O routines are called through a virtual function table. The os_test.c module has been replaced by test6.c. The crash tests are busted now and need to be fixed. (CVS 2785)
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Files: files | file ages | folders
SHA1:1f69aec285dd8e26bd739d5e44bb50fe03a9682a
User & Date: drh 2005-11-26 00:25:01
Context
2005-11-26
03:43
Add an OS method for making copies of file descriptors. This fixes the crash tests. (CVS 2786) check-in: 57a674fc user: drh tags: trunk
00:25
Modify the OS layer so that I/O routines are called through a virtual function table. The os_test.c module has been replaced by test6.c. The crash tests are busted now and need to be fixed. (CVS 2785) check-in: 1f69aec2 user: drh tags: trunk
2005-11-25
10:55
Ensure a low system limit on the number of open files does not cause manydb.test to fail. (CVS 2784) check-in: dba2cc0d user: danielk1977 tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to Makefile.in.

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  $(TOP)/src/pragma.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/test1.c \
  $(TOP)/src/test2.c \
  $(TOP)/src/test3.c \
  $(TOP)/src/test4.c \
  $(TOP)/src/test5.c \

  $(TOP)/src/utf.c \
  $(TOP)/src/util.c \
  $(TOP)/src/vdbe.c \
  $(TOP)/src/md5.c \
  $(TOP)/src/where.c

# Header files used by all library source files.
................................................................................
		 libsqlite3.la $(LIBTCL)

testfixture$(TEXE):	$(TOP)/src/tclsqlite.c libsqlite3.la $(TESTSRC)
	$(LTLINK) -DTCLSH=1 -DSQLITE_TEST=1 $(TEMP_STORE) \
		-o testfixture $(TESTSRC) $(TOP)/src/tclsqlite.c \
		libsqlite3.la $(LIBTCL)

crashtest$(TEXE):	$(TOP)/src/tclsqlite.c libsqlite3.la $(TESTSRC) $(TOP)/src/os_test.c
	$(LTLINK) -DOS_TEST=1 -DTCLSH=1 -DSQLITE_TEST=1 \
		-o crashtest \
		$(TESTSRC) $(TOP)/src/os_test.c $(TOP)/src/tclsqlite.c \
		libsqlite3.la $(LIBTCL)



fulltest:	testfixture$(TEXE) sqlite3$(TEXE) crashtest$(TEXE)
	./testfixture $(TOP)/test/all.test

test:	testfixture$(TEXE) sqlite3$(TEXE)
	./testfixture $(TOP)/test/quick.test

sqlite3_analyzer$(TEXE):	$(TOP)/src/tclsqlite.c libtclsqlite3.la \
				$(TESTSRC) $(TOP)/tool/spaceanal.tcl







>







 







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  $(TOP)/src/pragma.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/test1.c \
  $(TOP)/src/test2.c \
  $(TOP)/src/test3.c \
  $(TOP)/src/test4.c \
  $(TOP)/src/test5.c \
  $(TOP)/src/test6.c \
  $(TOP)/src/utf.c \
  $(TOP)/src/util.c \
  $(TOP)/src/vdbe.c \
  $(TOP)/src/md5.c \
  $(TOP)/src/where.c

# Header files used by all library source files.
................................................................................
		 libsqlite3.la $(LIBTCL)

testfixture$(TEXE):	$(TOP)/src/tclsqlite.c libsqlite3.la $(TESTSRC)
	$(LTLINK) -DTCLSH=1 -DSQLITE_TEST=1 $(TEMP_STORE) \
		-o testfixture $(TESTSRC) $(TOP)/src/tclsqlite.c \
		libsqlite3.la $(LIBTCL)









fulltest:	testfixture$(TEXE) sqlite3$(TEXE)
	./testfixture $(TOP)/test/all.test

test:	testfixture$(TEXE) sqlite3$(TEXE)
	./testfixture $(TOP)/test/quick.test

sqlite3_analyzer$(TEXE):	$(TOP)/src/tclsqlite.c libtclsqlite3.la \
				$(TESTSRC) $(TOP)/tool/spaceanal.tcl

Changes to main.mk.

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  $(TOP)/src/pragma.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/test1.c \
  $(TOP)/src/test2.c \
  $(TOP)/src/test3.c \
  $(TOP)/src/test4.c \
  $(TOP)/src/test5.c \

  $(TOP)/src/utf.c \
  $(TOP)/src/util.c \
  $(TOP)/src/vdbe.c \
  $(TOP)/src/md5.c \
  $(TOP)/src/where.c

# Header files used by all library source files.
................................................................................
		$(TOP)/src/tclsqlite.c libsqlite3.a $(LIBTCL) $(THREADLIB)

testfixture$(EXE):	$(TOP)/src/tclsqlite.c libsqlite3.a $(TESTSRC)
	$(TCCX) $(TCL_FLAGS) -DTCLSH=1 -DSQLITE_TEST=1 -o testfixture$(EXE) \
		$(TESTSRC) $(TOP)/src/tclsqlite.c \
		libsqlite3.a $(LIBTCL) $(THREADLIB)

crashtest:	$(TOP)/src/tclsqlite.c libsqlite3.a $(TESTSRC) $(TOP)/src/os_test.c
	$(TCCX) $(TCL_FLAGS) -DOS_TEST=1 -DTCLSH=1 -DSQLITE_TEST=1 \
		-o crashtest \
		$(TESTSRC) $(TOP)/src/os_test.c $(TOP)/src/tclsqlite.c \
		libsqlite3.a $(LIBTCL) $(THREADLIB)

fulltest:	testfixture$(EXE) sqlite3$(EXE) crashtest
	./testfixture$(EXE) $(TOP)/test/all.test

test:	testfixture$(EXE) sqlite3$(EXE)
	./testfixture$(EXE) $(TOP)/test/quick.test

sqlite3_analyzer$(EXE):	$(TOP)/src/tclsqlite.c libsqlite3.a $(TESTSRC) \
			$(TOP)/tool/spaceanal.tcl
................................................................................
#
install:	sqlite3 libsqlite3.a sqlite3.h
	mv sqlite3 /usr/bin
	mv libsqlite3.a /usr/lib
	mv sqlite3.h /usr/include

clean:	
	rm -f *.o sqlite3 libsqlite3.a sqlite3.h opcodes.* crashtest
	rm -f lemon lempar.c parse.* sqlite*.tar.gz mkkeywordhash keywordhash.h
	rm -f $(PUBLISH)
	rm -f *.da *.bb *.bbg gmon.out
	rm -rf tsrc







>







 







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  $(TOP)/src/pragma.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/test1.c \
  $(TOP)/src/test2.c \
  $(TOP)/src/test3.c \
  $(TOP)/src/test4.c \
  $(TOP)/src/test5.c \
  $(TOP)/src/test6.c \
  $(TOP)/src/utf.c \
  $(TOP)/src/util.c \
  $(TOP)/src/vdbe.c \
  $(TOP)/src/md5.c \
  $(TOP)/src/where.c

# Header files used by all library source files.
................................................................................
		$(TOP)/src/tclsqlite.c libsqlite3.a $(LIBTCL) $(THREADLIB)

testfixture$(EXE):	$(TOP)/src/tclsqlite.c libsqlite3.a $(TESTSRC)
	$(TCCX) $(TCL_FLAGS) -DTCLSH=1 -DSQLITE_TEST=1 -o testfixture$(EXE) \
		$(TESTSRC) $(TOP)/src/tclsqlite.c \
		libsqlite3.a $(LIBTCL) $(THREADLIB)







fulltest:	testfixture$(EXE) sqlite3$(EXE)
	./testfixture$(EXE) $(TOP)/test/all.test

test:	testfixture$(EXE) sqlite3$(EXE)
	./testfixture$(EXE) $(TOP)/test/quick.test

sqlite3_analyzer$(EXE):	$(TOP)/src/tclsqlite.c libsqlite3.a $(TESTSRC) \
			$(TOP)/tool/spaceanal.tcl
................................................................................
#
install:	sqlite3 libsqlite3.a sqlite3.h
	mv sqlite3 /usr/bin
	mv libsqlite3.a /usr/lib
	mv sqlite3.h /usr/include

clean:	
	rm -f *.o sqlite3 libsqlite3.a sqlite3.h opcodes.*
	rm -f lemon lempar.c parse.* sqlite*.tar.gz mkkeywordhash keywordhash.h
	rm -f $(PUBLISH)
	rm -f *.da *.bb *.bbg gmon.out
	rm -rf tsrc

Changes to src/os.h.

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#define PENDING_BYTE sqlite3_pending_byte
#endif

#define RESERVED_BYTE     (PENDING_BYTE+1)
#define SHARED_FIRST      (PENDING_BYTE+2)
#define SHARED_SIZE       510







int sqlite3OsDelete(const char*);
int sqlite3OsFileExists(const char*);
int sqlite3OsOpenReadWrite(const char*, OsFile*, int*);
int sqlite3OsOpenExclusive(const char*, OsFile*, int);
int sqlite3OsOpenReadOnly(const char*, OsFile*);
int sqlite3OsOpenDirectory(const char*, OsFile*);
int sqlite3OsSyncDirectory(const char*);

int sqlite3OsTempFileName(char*);
int sqlite3OsIsDirWritable(char*);
int sqlite3OsClose(OsFile*);

int sqlite3OsRead(OsFile*, void*, int amt);
int sqlite3OsWrite(OsFile*, const void*, int amt);
int sqlite3OsSeek(OsFile*, i64 offset);
int sqlite3OsSync(OsFile*, int);
int sqlite3OsTruncate(OsFile*, i64 size);
int sqlite3OsFileSize(OsFile*, i64 *pSize);
char *sqlite3OsFullPathname(const char*);

int sqlite3OsLock(OsFile*, int);
int sqlite3OsUnlock(OsFile*, int);
int sqlite3OsCheckReservedLock(OsFile *id);



/* The interface for file I/O is above.  Other miscellaneous functions
** are below */

int sqlite3OsRandomSeed(char*);
int sqlite3OsSleep(int ms);
int sqlite3OsCurrentTime(double*);
void sqlite3OsEnterMutex(void);
void sqlite3OsLeaveMutex(void);


#endif /* _SQLITE_OS_H_ */







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#define PENDING_BYTE sqlite3_pending_byte
#endif

#define RESERVED_BYTE     (PENDING_BYTE+1)
#define SHARED_FIRST      (PENDING_BYTE+2)
#define SHARED_SIZE       510


/*
** A single global instance of the following structure holds pointers to the
** various disk I/O routines.
*/
extern struct sqlite3IoVtbl {
  int (*xDelete)(const char*);
  int (*xFileExists)(const char*);
  int (*xOpenReadWrite)(const char*, OsFile*, int*);
  int (*xOpenExclusive)(const char*, OsFile*, int);
  int (*xOpenReadOnly)(const char*, OsFile*);
  int (*xOpenDirectory)(const char*, OsFile*);

  int (*xSyncDirectory)(const char*);
  int (*xTempFileName)(char*);
  int (*xIsDirWritable)(char*);

  int (*xClose)(OsFile*);
  int (*xRead)(OsFile*, void*, int amt);
  int (*xWrite)(OsFile*, const void*, int amt);
  int (*xSeek)(OsFile*, i64 offset);
  int (*xSync)(OsFile*, int);
  int (*xTruncate)(OsFile*, i64 size);
  int (*xFileSize)(OsFile*, i64 *pSize);

  char *(*xFullPathname)(const char*);
  int (*xLock)(OsFile*, int);
  int (*xUnlock)(OsFile*, int);
  int (*xCheckReservedLock)(OsFile *id);

} sqlite3Io;

/* The interface for file I/O is above.  Other miscellaneous functions
** are below */

int sqlite3OsRandomSeed(char*);
int sqlite3OsSleep(int ms);
int sqlite3OsCurrentTime(double*);
void sqlite3OsEnterMutex(void);
void sqlite3OsLeaveMutex(void);


#endif /* _SQLITE_OS_H_ */

Changes to src/os_unix.c.

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  *ppOpen = pOpen;
  return 0;
}

/*
** Delete the named file
*/
int sqlite3OsDelete(const char *zFilename){
  unlink(zFilename);
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
int sqlite3OsFileExists(const char *zFilename){
  return access(zFilename, 0)==0;
}

/*
** Attempt to open a file for both reading and writing.  If that
** fails, try opening it read-only.  If the file does not exist,
** try to create it.
................................................................................
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3OsOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
  int rc;
  assert( !id->isOpen );
  id->dirfd = -1;
................................................................................
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  int rc;
  assert( !id->isOpen );
  if( access(zFilename, 0)==0 ){
    return SQLITE_CANTOPEN;
  }
  SET_THREADID(id);
  id->dirfd = -1;
................................................................................
/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenReadOnly(const char *zFilename, OsFile *id){
  int rc;
  assert( !id->isOpen );
  SET_THREADID(id);
  id->dirfd = -1;
  id->h = open(zFilename, O_RDONLY|O_LARGEFILE|O_BINARY);
  if( id->h<0 ){
    return SQLITE_CANTOPEN;
................................................................................
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
int sqlite3OsOpenDirectory(
  const char *zDirname,
  OsFile *id
){
  if( !id->isOpen ){
    /* Do not open the directory if the corresponding file is not already
    ** open. */
    return SQLITE_CANTOPEN;
................................................................................
*/
char *sqlite3_temp_directory = 0;

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3OsTempFileName(char *zBuf){
  static const char *azDirs[] = {
     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };
................................................................................
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
  }while( access(zBuf,0)==0 );
  return SQLITE_OK; 
}

#ifndef SQLITE_OMIT_PAGER_PRAGMAS
/*
** Check that a given pathname is a directory and is writable 
**
*/
int sqlite3OsIsDirWritable(char *zBuf){

  struct stat buf;
  if( zBuf==0 ) return 0;
  if( zBuf[0]==0 ) return 0;
  if( stat(zBuf, &buf) ) return 0;
  if( !S_ISDIR(buf.st_mode) ) return 0;
  if( access(zBuf, 07) ) return 0;

  return 1;
}
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
int sqlite3OsRead(OsFile *id, void *pBuf, int amt){
  int got;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  TIMER_START;
  got = read(id->h, pBuf, amt);
  TIMER_END;
  TRACE5("READ    %-3d %5d %7d %d\n", id->h, got, last_page, TIMER_ELAPSED);
................................................................................
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
int sqlite3OsWrite(OsFile *id, const void *pBuf, int amt){
  int wrote = 0;
  assert( id->isOpen );
  assert( amt>0 );
  SimulateIOError(SQLITE_IOERR);
  SimulateDiskfullError;
  TIMER_START;
  while( amt>0 && (wrote = write(id->h, pBuf, amt))>0 ){
................................................................................
  }
  return SQLITE_OK;
}

/*
** Move the read/write pointer in a file.
*/
int sqlite3OsSeek(OsFile *id, i64 offset){
  assert( id->isOpen );
  SEEK(offset/1024 + 1);
#ifdef SQLITE_TEST
  if( offset ) SimulateDiskfullError
#endif
  lseek(id->h, offset, SEEK_SET);
  return SQLITE_OK;
................................................................................
** has been created by fsync-ing the directory that contains the file.
** If we do not do this and we encounter a power failure, the directory
** entry for the journal might not exist after we reboot.  The next
** SQLite to access the file will not know that the journal exists (because
** the directory entry for the journal was never created) and the transaction
** will not roll back - possibly leading to database corruption.
*/
int sqlite3OsSync(OsFile *id, int dataOnly){
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  TRACE2("SYNC    %-3d\n", id->h);
  if( full_fsync(id->h, id->fullSync, dataOnly) ){
    return SQLITE_IOERR;
  }
  if( id->dirfd>=0 ){
................................................................................
** Sync the directory zDirname. This is a no-op on operating systems other
** than UNIX.
**
** This is used to make sure the master journal file has truely been deleted
** before making changes to individual journals on a multi-database commit.
** The F_FULLFSYNC option is not needed here.
*/
int sqlite3OsSyncDirectory(const char *zDirname){
#ifdef SQLITE_DISABLE_DIRSYNC
  return SQLITE_OK;
#else
  int fd;
  int r;
  SimulateIOError(SQLITE_IOERR);
  fd = open(zDirname, O_RDONLY|O_BINARY, 0);
................................................................................
  return ((r==0)?SQLITE_OK:SQLITE_IOERR);
#endif
}

/*
** Truncate an open file to a specified size
*/
int sqlite3OsTruncate(OsFile *id, i64 nByte){
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  return ftruncate(id->h, nByte)==0 ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Determine the current size of a file in bytes
*/
int sqlite3OsFileSize(OsFile *id, i64 *pSize){
  struct stat buf;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  if( fstat(id->h, &buf)!=0 ){
    return SQLITE_IOERR;
  }
  *pSize = buf.st_size;
................................................................................

/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero.  If the file is unlocked or holds only SHARED locks, then
** return zero.
*/
int sqlite3OsCheckReservedLock(OsFile *id){
  int r = 0;

  assert( id->isOpen );
  if( CHECK_THREADID(id) ) return SQLITE_MISUSE;
  sqlite3OsEnterMutex(); /* Needed because id->pLock is shared across threads */

  /* Check if a thread in this process holds such a lock */
................................................................................
**    SHARED -> (PENDING) -> EXCLUSIVE
**    RESERVED -> (PENDING) -> EXCLUSIVE
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  Use the sqlite3OsUnlock()
** routine to lower a locking level.
*/
int sqlite3OsLock(OsFile *id, int locktype){
  /* The following describes the implementation of the various locks and
  ** lock transitions in terms of the POSIX advisory shared and exclusive
  ** lock primitives (called read-locks and write-locks below, to avoid
  ** confusion with SQLite lock names). The algorithms are complicated
  ** slightly in order to be compatible with windows systems simultaneously
  ** accessing the same database file, in case that is ever required.
  **
................................................................................
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK.  If the second argument is SHARED_LOCK, this routine
** might return SQLITE_IOERR instead of SQLITE_OK.
*/
int sqlite3OsUnlock(OsFile *id, int locktype){
  struct lockInfo *pLock;
  struct flock lock;
  int rc = SQLITE_OK;

  assert( id->isOpen );
  TRACE7("UNLOCK  %d %d was %d(%d,%d) pid=%d\n", id->h, locktype, id->locktype, 
      id->pLock->locktype, id->pLock->cnt, getpid());
................................................................................
  id->locktype = locktype;
  return rc;
}

/*
** Close a file.
*/
int sqlite3OsClose(OsFile *id){
  if( !id->isOpen ) return SQLITE_OK;
  if( CHECK_THREADID(id) ) return SQLITE_MISUSE;
  sqlite3OsUnlock(id, NO_LOCK);
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  sqlite3OsEnterMutex();
  if( id->pOpen->nLock ){
    /* If there are outstanding locks, do not actually close the file just
    ** yet because that would clear those locks.  Instead, add the file
    ** descriptor to pOpen->aPending.  It will be automatically closed when
................................................................................

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3OsFullPathname(const char *zRelative){
  char *zFull = 0;
  if( zRelative[0]=='/' ){
    sqlite3SetString(&zFull, zRelative, (char*)0);
  }else{
    char *zBuf = sqliteMalloc(5000);
    if( zBuf==0 ){
      return 0;
................................................................................
    sqlite3SetString(&zFull, getcwd(zBuf, 5000), "/", zRelative,
                    (char*)0);
    sqliteFree(zBuf);
  }
  return zFull;
}





























#endif /* SQLITE_OMIT_DISKIO */
/***************************************************************************
** Everything above deals with file I/O.  Everything that follows deals
** with other miscellanous aspects of the operating system interface
****************************************************************************/








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  *ppOpen = pOpen;
  return 0;
}

/*
** Delete the named file
*/
static int unixDelete(const char *zFilename){
  unlink(zFilename);
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
static int unixFileExists(const char *zFilename){
  return access(zFilename, 0)==0;
}

/*
** Attempt to open a file for both reading and writing.  If that
** fails, try opening it read-only.  If the file does not exist,
** try to create it.
................................................................................
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
static int unixOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
  int rc;
  assert( !id->isOpen );
  id->dirfd = -1;
................................................................................
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
static int unixOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  int rc;
  assert( !id->isOpen );
  if( access(zFilename, 0)==0 ){
    return SQLITE_CANTOPEN;
  }
  SET_THREADID(id);
  id->dirfd = -1;
................................................................................
/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
static int unixOpenReadOnly(const char *zFilename, OsFile *id){
  int rc;
  assert( !id->isOpen );
  SET_THREADID(id);
  id->dirfd = -1;
  id->h = open(zFilename, O_RDONLY|O_LARGEFILE|O_BINARY);
  if( id->h<0 ){
    return SQLITE_CANTOPEN;
................................................................................
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
static int unixOpenDirectory(
  const char *zDirname,
  OsFile *id
){
  if( !id->isOpen ){
    /* Do not open the directory if the corresponding file is not already
    ** open. */
    return SQLITE_CANTOPEN;
................................................................................
*/
char *sqlite3_temp_directory = 0;

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
static int unixTempFileName(char *zBuf){
  static const char *azDirs[] = {
     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };
................................................................................
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
  }while( access(zBuf,0)==0 );
  return SQLITE_OK; 
}


/*
** Check that a given pathname is a directory and is writable 
**
*/
static int unixIsDirWritable(char *zBuf){
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
  struct stat buf;
  if( zBuf==0 ) return 0;
  if( zBuf[0]==0 ) return 0;
  if( stat(zBuf, &buf) ) return 0;
  if( !S_ISDIR(buf.st_mode) ) return 0;
  if( access(zBuf, 07) ) return 0;
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
  return 1;
}


/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
static int unixRead(OsFile *id, void *pBuf, int amt){
  int got;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  TIMER_START;
  got = read(id->h, pBuf, amt);
  TIMER_END;
  TRACE5("READ    %-3d %5d %7d %d\n", id->h, got, last_page, TIMER_ELAPSED);
................................................................................
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
static int unixWrite(OsFile *id, const void *pBuf, int amt){
  int wrote = 0;
  assert( id->isOpen );
  assert( amt>0 );
  SimulateIOError(SQLITE_IOERR);
  SimulateDiskfullError;
  TIMER_START;
  while( amt>0 && (wrote = write(id->h, pBuf, amt))>0 ){
................................................................................
  }
  return SQLITE_OK;
}

/*
** Move the read/write pointer in a file.
*/
static int unixSeek(OsFile *id, i64 offset){
  assert( id->isOpen );
  SEEK(offset/1024 + 1);
#ifdef SQLITE_TEST
  if( offset ) SimulateDiskfullError
#endif
  lseek(id->h, offset, SEEK_SET);
  return SQLITE_OK;
................................................................................
** has been created by fsync-ing the directory that contains the file.
** If we do not do this and we encounter a power failure, the directory
** entry for the journal might not exist after we reboot.  The next
** SQLite to access the file will not know that the journal exists (because
** the directory entry for the journal was never created) and the transaction
** will not roll back - possibly leading to database corruption.
*/
static int unixSync(OsFile *id, int dataOnly){
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  TRACE2("SYNC    %-3d\n", id->h);
  if( full_fsync(id->h, id->fullSync, dataOnly) ){
    return SQLITE_IOERR;
  }
  if( id->dirfd>=0 ){
................................................................................
** Sync the directory zDirname. This is a no-op on operating systems other
** than UNIX.
**
** This is used to make sure the master journal file has truely been deleted
** before making changes to individual journals on a multi-database commit.
** The F_FULLFSYNC option is not needed here.
*/
static int unixSyncDirectory(const char *zDirname){
#ifdef SQLITE_DISABLE_DIRSYNC
  return SQLITE_OK;
#else
  int fd;
  int r;
  SimulateIOError(SQLITE_IOERR);
  fd = open(zDirname, O_RDONLY|O_BINARY, 0);
................................................................................
  return ((r==0)?SQLITE_OK:SQLITE_IOERR);
#endif
}

/*
** Truncate an open file to a specified size
*/
static int unixTruncate(OsFile *id, i64 nByte){
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  return ftruncate(id->h, nByte)==0 ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Determine the current size of a file in bytes
*/
static int unixFileSize(OsFile *id, i64 *pSize){
  struct stat buf;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  if( fstat(id->h, &buf)!=0 ){
    return SQLITE_IOERR;
  }
  *pSize = buf.st_size;
................................................................................

/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero.  If the file is unlocked or holds only SHARED locks, then
** return zero.
*/
static int unixCheckReservedLock(OsFile *id){
  int r = 0;

  assert( id->isOpen );
  if( CHECK_THREADID(id) ) return SQLITE_MISUSE;
  sqlite3OsEnterMutex(); /* Needed because id->pLock is shared across threads */

  /* Check if a thread in this process holds such a lock */
................................................................................
**    SHARED -> (PENDING) -> EXCLUSIVE
**    RESERVED -> (PENDING) -> EXCLUSIVE
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  Use the sqlite3OsUnlock()
** routine to lower a locking level.
*/
static int unixLock(OsFile *id, int locktype){
  /* The following describes the implementation of the various locks and
  ** lock transitions in terms of the POSIX advisory shared and exclusive
  ** lock primitives (called read-locks and write-locks below, to avoid
  ** confusion with SQLite lock names). The algorithms are complicated
  ** slightly in order to be compatible with windows systems simultaneously
  ** accessing the same database file, in case that is ever required.
  **
................................................................................
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK.  If the second argument is SHARED_LOCK, this routine
** might return SQLITE_IOERR instead of SQLITE_OK.
*/
static int unixUnlock(OsFile *id, int locktype){
  struct lockInfo *pLock;
  struct flock lock;
  int rc = SQLITE_OK;

  assert( id->isOpen );
  TRACE7("UNLOCK  %d %d was %d(%d,%d) pid=%d\n", id->h, locktype, id->locktype, 
      id->pLock->locktype, id->pLock->cnt, getpid());
................................................................................
  id->locktype = locktype;
  return rc;
}

/*
** Close a file.
*/
static int unixClose(OsFile *id){
  if( !id->isOpen ) return SQLITE_OK;
  if( CHECK_THREADID(id) ) return SQLITE_MISUSE;
  sqlite3Io.xUnlock(id, NO_LOCK);
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  sqlite3OsEnterMutex();
  if( id->pOpen->nLock ){
    /* If there are outstanding locks, do not actually close the file just
    ** yet because that would clear those locks.  Instead, add the file
    ** descriptor to pOpen->aPending.  It will be automatically closed when
................................................................................

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
static char *unixFullPathname(const char *zRelative){
  char *zFull = 0;
  if( zRelative[0]=='/' ){
    sqlite3SetString(&zFull, zRelative, (char*)0);
  }else{
    char *zBuf = sqliteMalloc(5000);
    if( zBuf==0 ){
      return 0;
................................................................................
    sqlite3SetString(&zFull, getcwd(zBuf, 5000), "/", zRelative,
                    (char*)0);
    sqliteFree(zBuf);
  }
  return zFull;
}


/*
** This is the structure that defines all of the I/O routines.
*/
struct sqlite3IoVtbl sqlite3Io = {
  unixDelete,
  unixFileExists,
  unixOpenReadWrite,
  unixOpenExclusive,
  unixOpenReadOnly,
  unixOpenDirectory,
  unixSyncDirectory,
  unixTempFileName,
  unixIsDirWritable,
  unixClose,
  unixRead,
  unixWrite,
  unixSeek,
  unixSync,
  unixTruncate,
  unixFileSize,
  unixFullPathname,
  unixLock,
  unixUnlock,
  unixCheckReservedLock,
};


#endif /* SQLITE_OMIT_DISKIO */
/***************************************************************************
** Everything above deals with file I/O.  Everything that follows deals
** with other miscellanous aspects of the operating system interface
****************************************************************************/

Changes to src/os_win.c.

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  return zFilename;
}


/*
** Delete the named file
*/
int sqlite3OsDelete(const char *zFilename){
  WCHAR *zWide = utf8ToUnicode(zFilename);
  if( zWide ){
    DeleteFileW(zWide);
    sqliteFree(zWide);
  }else{
    DeleteFileA(zFilename);
  }
................................................................................
  TRACE2("DELETE \"%s\"\n", zFilename);
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
int sqlite3OsFileExists(const char *zFilename){
  int exists = 0;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  if( zWide ){
    exists = GetFileAttributesW(zWide) != 0xffffffff;
    sqliteFree(zWide);
  }else{
    exists = GetFileAttributesA(zFilename) != 0xffffffff;
................................................................................
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3OsOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
  HANDLE h;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  assert( !id->isOpen );
................................................................................
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  HANDLE h;
  int fileflags;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  assert( !id->isOpen );
  if( delFlag ){
    fileflags = FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_RANDOM_ACCESS 
                     | FILE_FLAG_DELETE_ON_CLOSE;
................................................................................
/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenReadOnly(const char *zFilename, OsFile *id){
  HANDLE h;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  assert( !id->isOpen );
  if( zWide ){
    h = CreateFileW(zWide,
       GENERIC_READ,
       0,
................................................................................
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
int sqlite3OsOpenDirectory(
  const char *zDirname,
  OsFile *id
){
  return SQLITE_OK;
}

/*
................................................................................
*/
char *sqlite3_temp_directory = 0;

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3OsTempFileName(char *zBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[SQLITE_TEMPNAME_SIZE];
  if( sqlite3_temp_directory ){
................................................................................
    sprintf(zBuf, "%s\\"TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3OsFileExists(zBuf) ) break;
  }
  TRACE2("TEMP FILENAME: %s\n", zBuf);
  return SQLITE_OK; 
}

/*
** Close a file.
*/
int sqlite3OsClose(OsFile *id){
  if( id->isOpen ){
    TRACE2("CLOSE %d\n", id->h);
    CloseHandle(id->h);
    OpenCounter(-1);
    id->isOpen = 0;
  }
  return SQLITE_OK;
................................................................................
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
int sqlite3OsRead(OsFile *id, void *pBuf, int amt){
  DWORD got;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  TRACE3("READ %d lock=%d\n", id->h, id->locktype);
  if( !ReadFile(id->h, pBuf, amt, &got, 0) ){
    got = 0;
  }
................................................................................
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
int sqlite3OsWrite(OsFile *id, const void *pBuf, int amt){
  int rc = 0;
  DWORD wrote;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  SimulateDiskfullError;
  TRACE3("WRITE %d lock=%d\n", id->h, id->locktype);
  assert( amt>0 );
................................................................................
#ifndef INVALID_SET_FILE_POINTER
# define INVALID_SET_FILE_POINTER ((DWORD)-1)
#endif

/*
** Move the read/write pointer in a file.
*/
int sqlite3OsSeek(OsFile *id, i64 offset){
  LONG upperBits = offset>>32;
  LONG lowerBits = offset & 0xffffffff;
  DWORD rc;
  assert( id->isOpen );
#ifdef SQLITE_TEST
  if( offset ) SimulateDiskfullError
#endif
................................................................................
  }
  return SQLITE_OK;
}

/*
** Make sure all writes to a particular file are committed to disk.
*/
int sqlite3OsSync(OsFile *id, int dataOnly){
  assert( id->isOpen );
  TRACE3("SYNC %d lock=%d\n", id->h, id->locktype);
  if( FlushFileBuffers(id->h) ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*
** Sync the directory zDirname. This is a no-op on operating systems other
** than UNIX.
*/
int sqlite3OsSyncDirectory(const char *zDirname){
  SimulateIOError(SQLITE_IOERR);
  return SQLITE_OK;
}

/*
** Truncate an open file to a specified size
*/
int sqlite3OsTruncate(OsFile *id, i64 nByte){
  LONG upperBits = nByte>>32;
  assert( id->isOpen );
  TRACE3("TRUNCATE %d %lld\n", id->h, nByte);
  SimulateIOError(SQLITE_IOERR);
  SetFilePointer(id->h, nByte, &upperBits, FILE_BEGIN);
  SetEndOfFile(id->h);
  return SQLITE_OK;
}

/*
** Determine the current size of a file in bytes
*/
int sqlite3OsFileSize(OsFile *id, i64 *pSize){
  DWORD upperBits, lowerBits;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  lowerBits = GetFileSize(id->h, &upperBits);
  *pSize = (((i64)upperBits)<<32) + lowerBits;
  return SQLITE_OK;
}
................................................................................
}

#ifndef SQLITE_OMIT_PAGER_PRAGMAS
/*
** Check that a given pathname is a directory and is writable 
**
*/
int sqlite3OsIsDirWritable(char *zDirname){
  int fileAttr;
  WCHAR *zWide;
  if( zDirname==0 ) return 0;
  if( !isNT() && strlen(zDirname)>MAX_PATH ) return 0;
  zWide = utf8ToUnicode(zDirname);
  if( zWide ){
    fileAttr = GetFileAttributesW(zWide);
................................................................................
**
**    UNLOCKED -> SHARED
**    SHARED -> RESERVED
**    SHARED -> (PENDING) -> EXCLUSIVE
**    RESERVED -> (PENDING) -> EXCLUSIVE
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  The sqlite3OsUnlock() routine
** erases all locks at once and returns us immediately to locking level 0.
** It is not possible to lower the locking level one step at a time.  You
** must go straight to locking level 0.
*/
int sqlite3OsLock(OsFile *id, int locktype){
  int rc = SQLITE_OK;    /* Return code from subroutines */
  int res = 1;           /* Result of a windows lock call */
  int newLocktype;       /* Set id->locktype to this value before exiting */
  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */

  assert( id->isOpen );
  TRACE5("LOCK %d %d was %d(%d)\n",
................................................................................
}

/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero, otherwise zero.
*/
int sqlite3OsCheckReservedLock(OsFile *id){
  int rc;
  assert( id->isOpen );
  if( id->locktype>=RESERVED_LOCK ){
    rc = 1;
    TRACE3("TEST WR-LOCK %d %d (local)\n", id->h, rc);
  }else{
    rc = LockFile(id->h, RESERVED_BYTE, 0, 1, 0);
................................................................................
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
** might return SQLITE_IOERR;
*/
int sqlite3OsUnlock(OsFile *id, int locktype){
  int type;
  int rc = SQLITE_OK;
  assert( id->isOpen );
  assert( locktype<=SHARED_LOCK );
  TRACE5("UNLOCK %d to %d was %d(%d)\n", id->h, locktype,
          id->locktype, id->sharedLockByte);
  type = id->locktype;
................................................................................

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3OsFullPathname(const char *zRelative){
  char *zNotUsed;
  char *zFull;
  WCHAR *zWide;
  int nByte;
#ifdef __CYGWIN__
  nByte = strlen(zRelative) + MAX_PATH + 1001;
  zFull = sqliteMalloc( nByte );
................................................................................
    zFull = sqliteMalloc( nByte*sizeof(zFull[0]) );
    if( zFull==0 ) return 0;
    GetFullPathNameA(zRelative, nByte, zFull, &zNotUsed);
  }
#endif
  return zFull;
}



























#endif /* SQLITE_OMIT_DISKIO */
/***************************************************************************
** Everything above deals with file I/O.  Everything that follows deals
** with other miscellanous aspects of the operating system interface
****************************************************************************/








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  return zFilename;
}


/*
** Delete the named file
*/
static int winDelete(const char *zFilename){
  WCHAR *zWide = utf8ToUnicode(zFilename);
  if( zWide ){
    DeleteFileW(zWide);
    sqliteFree(zWide);
  }else{
    DeleteFileA(zFilename);
  }
................................................................................
  TRACE2("DELETE \"%s\"\n", zFilename);
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
static int winFileExists(const char *zFilename){
  int exists = 0;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  if( zWide ){
    exists = GetFileAttributesW(zWide) != 0xffffffff;
    sqliteFree(zWide);
  }else{
    exists = GetFileAttributesA(zFilename) != 0xffffffff;
................................................................................
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
static int winOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
  HANDLE h;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  assert( !id->isOpen );
................................................................................
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
static int winOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  HANDLE h;
  int fileflags;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  assert( !id->isOpen );
  if( delFlag ){
    fileflags = FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_RANDOM_ACCESS 
                     | FILE_FLAG_DELETE_ON_CLOSE;
................................................................................
/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
static int winOpenReadOnly(const char *zFilename, OsFile *id){
  HANDLE h;
  WCHAR *zWide = utf8ToUnicode(zFilename);
  assert( !id->isOpen );
  if( zWide ){
    h = CreateFileW(zWide,
       GENERIC_READ,
       0,
................................................................................
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
static int winOpenDirectory(
  const char *zDirname,
  OsFile *id
){
  return SQLITE_OK;
}

/*
................................................................................
*/
char *sqlite3_temp_directory = 0;

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
static int winTempFileName(char *zBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[SQLITE_TEMPNAME_SIZE];
  if( sqlite3_temp_directory ){
................................................................................
    sprintf(zBuf, "%s\\"TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3Io.xFileExists(zBuf) ) break;
  }
  TRACE2("TEMP FILENAME: %s\n", zBuf);
  return SQLITE_OK; 
}

/*
** Close a file.
*/
static int winClose(OsFile *id){
  if( id->isOpen ){
    TRACE2("CLOSE %d\n", id->h);
    CloseHandle(id->h);
    OpenCounter(-1);
    id->isOpen = 0;
  }
  return SQLITE_OK;
................................................................................
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
static int winRead(OsFile *id, void *pBuf, int amt){
  DWORD got;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  TRACE3("READ %d lock=%d\n", id->h, id->locktype);
  if( !ReadFile(id->h, pBuf, amt, &got, 0) ){
    got = 0;
  }
................................................................................
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
static int winWrite(OsFile *id, const void *pBuf, int amt){
  int rc = 0;
  DWORD wrote;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  SimulateDiskfullError;
  TRACE3("WRITE %d lock=%d\n", id->h, id->locktype);
  assert( amt>0 );
................................................................................
#ifndef INVALID_SET_FILE_POINTER
# define INVALID_SET_FILE_POINTER ((DWORD)-1)
#endif

/*
** Move the read/write pointer in a file.
*/
static int winSeek(OsFile *id, i64 offset){
  LONG upperBits = offset>>32;
  LONG lowerBits = offset & 0xffffffff;
  DWORD rc;
  assert( id->isOpen );
#ifdef SQLITE_TEST
  if( offset ) SimulateDiskfullError
#endif
................................................................................
  }
  return SQLITE_OK;
}

/*
** Make sure all writes to a particular file are committed to disk.
*/
static int winSync(OsFile *id, int dataOnly){
  assert( id->isOpen );
  TRACE3("SYNC %d lock=%d\n", id->h, id->locktype);
  if( FlushFileBuffers(id->h) ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*
** Sync the directory zDirname. This is a no-op on operating systems other
** than UNIX.
*/
static int winSyncDirectory(const char *zDirname){
  SimulateIOError(SQLITE_IOERR);
  return SQLITE_OK;
}

/*
** Truncate an open file to a specified size
*/
static int winTruncate(OsFile *id, i64 nByte){
  LONG upperBits = nByte>>32;
  assert( id->isOpen );
  TRACE3("TRUNCATE %d %lld\n", id->h, nByte);
  SimulateIOError(SQLITE_IOERR);
  SetFilePointer(id->h, nByte, &upperBits, FILE_BEGIN);
  SetEndOfFile(id->h);
  return SQLITE_OK;
}

/*
** Determine the current size of a file in bytes
*/
static int winFileSize(OsFile *id, i64 *pSize){
  DWORD upperBits, lowerBits;
  assert( id->isOpen );
  SimulateIOError(SQLITE_IOERR);
  lowerBits = GetFileSize(id->h, &upperBits);
  *pSize = (((i64)upperBits)<<32) + lowerBits;
  return SQLITE_OK;
}
................................................................................
}

#ifndef SQLITE_OMIT_PAGER_PRAGMAS
/*
** Check that a given pathname is a directory and is writable 
**
*/
static int winIsDirWritable(char *zDirname){
  int fileAttr;
  WCHAR *zWide;
  if( zDirname==0 ) return 0;
  if( !isNT() && strlen(zDirname)>MAX_PATH ) return 0;
  zWide = utf8ToUnicode(zDirname);
  if( zWide ){
    fileAttr = GetFileAttributesW(zWide);
................................................................................
**
**    UNLOCKED -> SHARED
**    SHARED -> RESERVED
**    SHARED -> (PENDING) -> EXCLUSIVE
**    RESERVED -> (PENDING) -> EXCLUSIVE
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  The winUnlock() routine
** erases all locks at once and returns us immediately to locking level 0.
** It is not possible to lower the locking level one step at a time.  You
** must go straight to locking level 0.
*/
static int winLock(OsFile *id, int locktype){
  int rc = SQLITE_OK;    /* Return code from subroutines */
  int res = 1;           /* Result of a windows lock call */
  int newLocktype;       /* Set id->locktype to this value before exiting */
  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */

  assert( id->isOpen );
  TRACE5("LOCK %d %d was %d(%d)\n",
................................................................................
}

/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero, otherwise zero.
*/
static int winCheckReservedLock(OsFile *id){
  int rc;
  assert( id->isOpen );
  if( id->locktype>=RESERVED_LOCK ){
    rc = 1;
    TRACE3("TEST WR-LOCK %d %d (local)\n", id->h, rc);
  }else{
    rc = LockFile(id->h, RESERVED_BYTE, 0, 1, 0);
................................................................................
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
** might return SQLITE_IOERR;
*/
static int winUnlock(OsFile *id, int locktype){
  int type;
  int rc = SQLITE_OK;
  assert( id->isOpen );
  assert( locktype<=SHARED_LOCK );
  TRACE5("UNLOCK %d to %d was %d(%d)\n", id->h, locktype,
          id->locktype, id->sharedLockByte);
  type = id->locktype;
................................................................................

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
static char *winFullPathname(const char *zRelative){
  char *zNotUsed;
  char *zFull;
  WCHAR *zWide;
  int nByte;
#ifdef __CYGWIN__
  nByte = strlen(zRelative) + MAX_PATH + 1001;
  zFull = sqliteMalloc( nByte );
................................................................................
    zFull = sqliteMalloc( nByte*sizeof(zFull[0]) );
    if( zFull==0 ) return 0;
    GetFullPathNameA(zRelative, nByte, zFull, &zNotUsed);
  }
#endif
  return zFull;
}

/*
** This is the structure that defines all of the I/O routines.
*/
struct sqlite3IoVtbl sqlite3Io = {
  winDelete,
  winFileExists,
  winOpenReadWrite,
  winOpenExclusive,
  winOpenReadOnly,
  winOpenDirectory,
  winSyncDirectory,
  winTempFileName,
  winIsDirWritable,
  winClose,
  winRead,
  winWrite,
  winSeek,
  winSync,
  winTruncate,
  winFileSize,
  winFullPathname,
  winLock,
  winUnlock,
  winCheckReservedLock,
};

#endif /* SQLITE_OMIT_DISKIO */
/***************************************************************************
** Everything above deals with file I/O.  Everything that follows deals
** with other miscellanous aspects of the operating system interface
****************************************************************************/

Changes to src/pager.c.

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1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
....
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
....
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
....
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
....
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
....
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
....
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
....
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
....
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
....
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
....
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
....
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
....
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
....
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
....
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
....
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
....
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
....
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
....
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
....
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
....
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247

2248
2249
2250
2251
2252
2253
2254
....
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
....
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
....
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550

2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
....
2671
2672
2673
2674
2675
2676
2677
2678

2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
....
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
....
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
....
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
....
2912
2913
2914
2915
2916
2917
2918
2919

2920
2921
2922
2923
2924
2925
2926
....
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
....
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
....
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
....
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.217 2005/11/05 15:11:23 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>
................................................................................
** error code is something goes wrong.
**
** All values are stored on disk as big-endian.
*/
static int read32bits(OsFile *fd, u32 *pRes){
  u32 res;
  int rc;
  rc = sqlite3OsRead(fd, &res, sizeof(res));
  if( rc==SQLITE_OK ){
    unsigned char ac[4];
    memcpy(ac, &res, 4);
    res = (ac[0]<<24) | (ac[1]<<16) | (ac[2]<<8) | ac[3];
  }
  *pRes = res;
  return rc;
................................................................................
*/
static int write32bits(OsFile *fd, u32 val){
  unsigned char ac[4];
  ac[0] = (val>>24) & 0xff;
  ac[1] = (val>>16) & 0xff;
  ac[2] = (val>>8) & 0xff;
  ac[3] = val & 0xff;
  return sqlite3OsWrite(fd, ac, 4);
}

/*
** Write the 32-bit integer 'val' into the page identified by page header
** 'p' at offset 'offset'.
*/
static void store32bits(u32 val, PgHdr *p, int offset){
................................................................................
  i64 szJ;
  u32 cksum;
  int i;
  unsigned char aMagic[8]; /* A buffer to hold the magic header */

  *pzMaster = 0;

  rc = sqlite3OsFileSize(pJrnl, &szJ);
  if( rc!=SQLITE_OK || szJ<16 ) return rc;

  rc = sqlite3OsSeek(pJrnl, szJ-16);
  if( rc!=SQLITE_OK ) return rc;
 
  rc = read32bits(pJrnl, &len);
  if( rc!=SQLITE_OK ) return rc;

  rc = read32bits(pJrnl, &cksum);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3OsRead(pJrnl, aMagic, 8);
  if( rc!=SQLITE_OK || memcmp(aMagic, aJournalMagic, 8) ) return rc;

  rc = sqlite3OsSeek(pJrnl, szJ-16-len);
  if( rc!=SQLITE_OK ) return rc;

  *pzMaster = (char *)sqliteMalloc(len+1);
  if( !*pzMaster ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3OsRead(pJrnl, *pzMaster, len);
  if( rc!=SQLITE_OK ){
    sqliteFree(*pzMaster);
    *pzMaster = 0;
    return rc;
  }

  /* See if the checksum matches the master journal name */
................................................................................
  if( c ){
    offset = ((c-1)/JOURNAL_HDR_SZ(pPager) + 1) * JOURNAL_HDR_SZ(pPager);
  }
  assert( offset%JOURNAL_HDR_SZ(pPager)==0 );
  assert( offset>=c );
  assert( (offset-c)<JOURNAL_HDR_SZ(pPager) );
  pPager->journalOff = offset;
  return sqlite3OsSeek(&pPager->jfd, pPager->journalOff);
}

/*
** The journal file must be open when this routine is called. A journal
** header (JOURNAL_HDR_SZ bytes) is written into the journal file at the
** current location.
**
................................................................................
  **
  ** Possibly for a pager not in no-sync mode, the journal magic should not
  ** be written until nRec is filled in as part of next syncJournal(). 
  **
  ** Actually maybe the whole journal header should be delayed until that
  ** point. Think about this.
  */
  rc = sqlite3OsWrite(&pPager->jfd, aJournalMagic, sizeof(aJournalMagic));

  if( rc==SQLITE_OK ){
    /* The nRec Field. 0xFFFFFFFF for no-sync journals. */
    rc = write32bits(&pPager->jfd, pPager->noSync ? 0xffffffff : 0);
  }
  if( rc==SQLITE_OK ){
    /* The random check-hash initialiser */ 
................................................................................
    rc = write32bits(&pPager->jfd, pPager->sectorSize);
  }

  /* The journal header has been written successfully. Seek the journal
  ** file descriptor to the end of the journal header sector.
  */
  if( rc==SQLITE_OK ){
    rc = sqlite3OsSeek(&pPager->jfd, pPager->journalOff-1);
    if( rc==SQLITE_OK ){
      rc = sqlite3OsWrite(&pPager->jfd, "\000", 1);
    }
  }
  return rc;
}

/*
** The journal file must be open when this is called. A journal header file
................................................................................
  rc = seekJournalHdr(pPager);
  if( rc ) return rc;

  if( pPager->journalOff+JOURNAL_HDR_SZ(pPager) > journalSize ){
    return SQLITE_DONE;
  }

  rc = sqlite3OsRead(&pPager->jfd, aMagic, sizeof(aMagic));
  if( rc ) return rc;

  if( memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
    return SQLITE_DONE;
  }

  rc = read32bits(&pPager->jfd, pNRec);
................................................................................
  ** is being called from within pager_playback(). The local value
  ** of Pager.sectorSize is restored at the end of that routine.
  */
  rc = read32bits(&pPager->jfd, (u32 *)&pPager->sectorSize);
  if( rc ) return rc;

  pPager->journalOff += JOURNAL_HDR_SZ(pPager);
  rc = sqlite3OsSeek(&pPager->jfd, pPager->journalOff);
  return rc;
}


/*
** Write the supplied master journal name into the journal file for pager
** pPager at the current location. The master journal name must be the last
................................................................................
    if( rc!=SQLITE_OK ) return rc;
  }
  pPager->journalOff += (len+20);

  rc = write32bits(&pPager->jfd, PAGER_MJ_PGNO(pPager));
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3OsWrite(&pPager->jfd, zMaster, len);
  if( rc!=SQLITE_OK ) return rc;

  rc = write32bits(&pPager->jfd, len);
  if( rc!=SQLITE_OK ) return rc;

  rc = write32bits(&pPager->jfd, cksum);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3OsWrite(&pPager->jfd, aJournalMagic, sizeof(aJournalMagic));
  pPager->needSync = !pPager->noSync;
  return rc;
}

/*
** Add or remove a page from the list of all pages that are in the
** statement journal.
................................................................................
  pPager->pLast = 0;
  pPager->pAll = 0;
  memset(pPager->aHash, 0, sizeof(pPager->aHash));
  pPager->nPage = 0;
  if( pPager->state>=PAGER_RESERVED ){
    sqlite3pager_rollback(pPager);
  }
  sqlite3OsUnlock(&pPager->fd, NO_LOCK);
  pPager->state = PAGER_UNLOCK;
  pPager->dbSize = -1;
  pPager->nRef = 0;
  assert( pPager->journalOpen==0 );
}

/*
................................................................................
  int rc;
  assert( !MEMDB );
  if( pPager->state<PAGER_RESERVED ){
    return SQLITE_OK;
  }
  sqlite3pager_stmt_commit(pPager);
  if( pPager->stmtOpen ){
    sqlite3OsClose(&pPager->stfd);
    pPager->stmtOpen = 0;
  }
  if( pPager->journalOpen ){
    sqlite3OsClose(&pPager->jfd);
    pPager->journalOpen = 0;
    sqlite3OsDelete(pPager->zJournal);
    sqliteFree( pPager->aInJournal );
    pPager->aInJournal = 0;
    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
      pPg->inJournal = 0;
      pPg->dirty = 0;
      pPg->needSync = 0;
#ifdef SQLITE_CHECK_PAGES
................................................................................
    }
    pPager->dirtyCache = 0;
    pPager->nRec = 0;
  }else{
    assert( pPager->aInJournal==0 );
    assert( pPager->dirtyCache==0 || pPager->useJournal==0 );
  }
  rc = sqlite3OsUnlock(&pPager->fd, SHARED_LOCK);
  pPager->state = PAGER_SHARED;
  pPager->origDbSize = 0;
  pPager->setMaster = 0;
  return rc;
}

/*
................................................................................
  ** statement journals.  Verify that this is always the case
  */
  assert( jfd == (useCksum ? &pPager->jfd : &pPager->stfd) );


  rc = read32bits(jfd, &pgno);
  if( rc!=SQLITE_OK ) return rc;
  rc = sqlite3OsRead(jfd, &aData, pPager->pageSize);
  if( rc!=SQLITE_OK ) return rc;
  pPager->journalOff += pPager->pageSize + 4;

  /* Sanity checking on the page.  This is more important that I originally
  ** thought.  If a power failure occurs while the journal is being written,
  ** it could cause invalid data to be written into the journal.  We need to
  ** detect this invalid data (with high probability) and ignore it.
................................................................................
  ** page content is in the main journal either because the page is not in
  ** cache or else it is marked as needSync==0.
  */
  pPg = pager_lookup(pPager, pgno);
  assert( pPager->state>=PAGER_EXCLUSIVE || pPg!=0 );
  TRACE3("PLAYBACK %d page %d\n", PAGERID(pPager), pgno);
  if( pPager->state>=PAGER_EXCLUSIVE && (pPg==0 || pPg->needSync==0) ){
    rc = sqlite3OsSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
    if( rc==SQLITE_OK ){
      rc = sqlite3OsWrite(&pPager->fd, aData, pPager->pageSize);
    }
    if( pPg ) pPg->dirty = 0;
  }
  if( pPg ){
    /* No page should ever be explicitly rolled back that is in use, except
    ** for page 1 which is held in use in order to keep the lock on the
    ** database active. However such a page may be rolled back as a result
................................................................................
  char *zMasterJournal = 0; /* Contents of master journal file */
  i64 nMasterJournal;       /* Size of master journal file */

  /* Open the master journal file exclusively in case some other process
  ** is running this routine also. Not that it makes too much difference.
  */
  memset(&master, 0, sizeof(master));
  rc = sqlite3OsOpenReadOnly(zMaster, &master);
  if( rc!=SQLITE_OK ) goto delmaster_out;
  master_open = 1;
  rc = sqlite3OsFileSize(&master, &nMasterJournal);
  if( rc!=SQLITE_OK ) goto delmaster_out;

  if( nMasterJournal>0 ){
    char *zJournal;
    char *zMasterPtr = 0;

    /* Load the entire master journal file into space obtained from
................................................................................
    ** sqliteMalloc() and pointed to by zMasterJournal. 
    */
    zMasterJournal = (char *)sqliteMalloc(nMasterJournal);
    if( !zMasterJournal ){
      rc = SQLITE_NOMEM;
      goto delmaster_out;
    }
    rc = sqlite3OsRead(&master, zMasterJournal, nMasterJournal);
    if( rc!=SQLITE_OK ) goto delmaster_out;

    zJournal = zMasterJournal;
    while( (zJournal-zMasterJournal)<nMasterJournal ){
      if( sqlite3OsFileExists(zJournal) ){
        /* One of the journals pointed to by the master journal exists.
        ** Open it and check if it points at the master journal. If
        ** so, return without deleting the master journal file.
        */
        OsFile journal;
        int c;

        memset(&journal, 0, sizeof(journal));
        rc = sqlite3OsOpenReadOnly(zJournal, &journal);
        if( rc!=SQLITE_OK ){
          goto delmaster_out;
        }

        rc = readMasterJournal(&journal, &zMasterPtr);
        sqlite3OsClose(&journal);
        if( rc!=SQLITE_OK ){
          goto delmaster_out;
        }

        c = zMasterPtr!=0 && strcmp(zMasterPtr, zMaster)==0;
        sqliteFree(zMasterPtr);
        if( c ){
................................................................................
          goto delmaster_out;
        }
      }
      zJournal += (strlen(zJournal)+1);
    }
  }
  
  sqlite3OsDelete(zMaster);

delmaster_out:
  if( zMasterJournal ){
    sqliteFree(zMasterJournal);
  }  
  if( master_open ){
    sqlite3OsClose(&master);
  }
  return rc;
}

/*
** Make every page in the cache agree with what is on disk.  In other words,
** reread the disk to reset the state of the cache.
................................................................................
static int pager_reload_cache(Pager *pPager){
  PgHdr *pPg;
  int rc = SQLITE_OK;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    char zBuf[SQLITE_MAX_PAGE_SIZE];
    if( !pPg->dirty ) continue;
    if( (int)pPg->pgno <= pPager->origDbSize ){
      rc = sqlite3OsSeek(&pPager->fd, pPager->pageSize*(i64)(pPg->pgno-1));
      if( rc==SQLITE_OK ){
        rc = sqlite3OsRead(&pPager->fd, zBuf, pPager->pageSize);
      }
      TRACE3("REFETCH %d page %d\n", PAGERID(pPager), pPg->pgno);
      if( rc ) break;
      CODEC(pPager, zBuf, pPg->pgno, 2);
    }else{
      memset(zBuf, 0, pPager->pageSize);
    }
................................................................................

/*
** Truncate the main file of the given pager to the number of pages
** indicated.
*/
static int pager_truncate(Pager *pPager, int nPage){
  assert( pPager->state>=PAGER_EXCLUSIVE );
  return sqlite3OsTruncate(&pPager->fd, pPager->pageSize*(i64)nPage);
}

/*
** Playback the journal and thus restore the database file to
** the state it was in before we started making changes.  
**
** The journal file format is as follows: 
................................................................................
  int rc;                  /* Result code of a subroutine */
  char *zMaster = 0;       /* Name of master journal file if any */

  /* Figure out how many records are in the journal.  Abort early if
  ** the journal is empty.
  */
  assert( pPager->journalOpen );
  rc = sqlite3OsFileSize(&pPager->jfd, &szJ);
  if( rc!=SQLITE_OK ){
    goto end_playback;
  }

  /* Read the master journal name from the journal, if it is present.
  ** If a master journal file name is specified, but the file is not
  ** present on disk, then the journal is not hot and does not need to be
  ** played back.
  */
  rc = readMasterJournal(&pPager->jfd, &zMaster);
  assert( rc!=SQLITE_DONE );
  if( rc!=SQLITE_OK || (zMaster && !sqlite3OsFileExists(zMaster)) ){
    sqliteFree(zMaster);
    zMaster = 0;
    if( rc==SQLITE_DONE ) rc = SQLITE_OK;
    goto end_playback;
  }
  sqlite3OsSeek(&pPager->jfd, 0);
  pPager->journalOff = 0;

  /* This loop terminates either when the readJournalHdr() call returns
  ** SQLITE_DONE or an IO error occurs. */
  while( 1 ){

    /* Read the next journal header from the journal file.  If there are
................................................................................
      rc = pager_truncate(pPager, mxPg);
      if( rc!=SQLITE_OK ){
        goto end_playback;
      }
      pPager->dbSize = mxPg;
    }

    /* rc = sqlite3OsSeek(&pPager->jfd, JOURNAL_HDR_SZ(pPager)); */
    if( rc!=SQLITE_OK ) goto end_playback;
  
    /* Copy original pages out of the journal and back into the database file.
    */
    for(i=0; i<nRec; i++){
      rc = pager_playback_one_page(pPager, &pPager->jfd, 1);
      if( rc!=SQLITE_OK ){
................................................................................
  int i;                   /* Loop counter */
  int rc;

  szJ = pPager->journalOff;
#ifndef NDEBUG 
  {
    i64 os_szJ;
    rc = sqlite3OsFileSize(&pPager->jfd, &os_szJ);
    if( rc!=SQLITE_OK ) return rc;
    assert( szJ==os_szJ );
  }
#endif

  /* Set hdrOff to be the offset to the first journal header written
  ** this statement transaction, or the end of the file if no journal
................................................................................
    rc = pager_truncate(pPager, pPager->stmtSize);
  }
  pPager->dbSize = pPager->stmtSize;

  /* Figure out how many records are in the statement journal.
  */
  assert( pPager->stmtInUse && pPager->journalOpen );
  sqlite3OsSeek(&pPager->stfd, 0);
  nRec = pPager->stmtNRec;
  
  /* Copy original pages out of the statement journal and back into the
  ** database file.  Note that the statement journal omits checksums from
  ** each record since power-failure recovery is not important to statement
  ** journals.
  */
................................................................................
  ** was the size of the journal file when this statement was started, so
  ** everything after that needs to be rolled back, either into the
  ** database, the memory cache, or both.
  **
  ** If it is not zero, then Pager.stmtHdrOff is the offset to the start
  ** of the first journal header written during this statement transaction.
  */
  rc = sqlite3OsSeek(&pPager->jfd, pPager->stmtJSize);
  if( rc!=SQLITE_OK ){
    goto end_stmt_playback;
  }
  pPager->journalOff = pPager->stmtJSize;
  pPager->cksumInit = pPager->stmtCksum;
  assert( JOURNAL_HDR_SZ(pPager)<(pPager->pageSize+8) );
  while( pPager->journalOff <= (hdrOff-(pPager->pageSize+8)) ){
................................................................................
}

/*
** Adjust the robustness of the database to damage due to OS crashes
** or power failures by changing the number of syncs()s when writing
** the rollback journal.  There are three levels:
**
**    OFF       sqlite3OsSync() is never called.  This is the default
**              for temporary and transient files.
**
**    NORMAL    The journal is synced once before writes begin on the
**              database.  This is normally adequate protection, but
**              it is theoretically possible, though very unlikely,
**              that an inopertune power failure could leave the journal
**              in a state which would cause damage to the database
................................................................................
*/
static int sqlite3pager_opentemp(char *zFile, OsFile *fd){
  int cnt = 8;
  int rc;
  sqlite3_opentemp_count++;  /* Used for testing and analysis only */
  do{
    cnt--;
    sqlite3OsTempFileName(zFile);
    rc = sqlite3OsOpenExclusive(zFile, fd, 1);
  }while( cnt>0 && rc!=SQLITE_OK && rc!=SQLITE_NOMEM );
  return rc;
}

/*
** Create a new page cache and put a pointer to the page cache in *ppPager.
** The file to be cached need not exist.  The file is not locked until
................................................................................
    if( strcmp(zFilename,":memory:")==0 ){
      memDb = 1;
      zFullPathname = sqliteStrDup("");
      rc = SQLITE_OK;
    }else
#endif
    {
      zFullPathname = sqlite3OsFullPathname(zFilename);
      if( zFullPathname ){
        rc = sqlite3OsOpenReadWrite(zFullPathname, &fd, &readOnly);
      }
    }
  }else{
    rc = sqlite3pager_opentemp(zTemp, &fd);
    zFilename = zTemp;
    zFullPathname = sqlite3OsFullPathname(zFilename);
    if( rc==SQLITE_OK ){
      tempFile = 1;
    }
  }
  if( !zFullPathname ){
    sqlite3OsClose(&fd);
    return SQLITE_NOMEM;
  }
  if( rc!=SQLITE_OK ){
    sqlite3OsClose(&fd);
    sqliteFree(zFullPathname);
    return rc;
  }
  nameLen = strlen(zFullPathname);
  pPager = sqliteMalloc( sizeof(*pPager) + nameLen*3 + 30 );
  if( pPager==0 ){
    sqlite3OsClose(&fd);
    sqliteFree(zFullPathname);
    return SQLITE_NOMEM;
  }
  TRACE3("OPEN %d %s\n", FILEHANDLEID(fd), zFullPathname);
  pPager->zFilename = (char*)&pPager[1];
  pPager->zDirectory = &pPager->zFilename[nameLen+1];
  pPager->zJournal = &pPager->zDirectory[nameLen+1];
................................................................................
  strcpy(pPager->zDirectory, zFullPathname);
  for(i=nameLen; i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;
  strcpy(pPager->zJournal, zFullPathname);
  sqliteFree(zFullPathname);
  strcpy(&pPager->zJournal[nameLen], "-journal");
  pPager->fd = fd;
#if OS_UNIX
  pPager->fd.pPager = pPager;
#endif
  pPager->journalOpen = 0;
  pPager->useJournal = useJournal && !memDb;
  pPager->noReadlock = noReadlock && readOnly;
  pPager->stmtOpen = 0;
  pPager->stmtInUse = 0;
  pPager->nRef = 0;
  pPager->dbSize = memDb-1;
................................................................................
/*
** Read the first N bytes from the beginning of the file into memory
** that pDest points to.  No error checking is done.
*/
void sqlite3pager_read_fileheader(Pager *pPager, int N, unsigned char *pDest){
  memset(pDest, 0, N);
  if( MEMDB==0 ){
    sqlite3OsSeek(&pPager->fd, 0);
    sqlite3OsRead(&pPager->fd, pDest, N);
    clear_simulated_io_error();
  }
}

/*
** Return the total number of pages in the disk file associated with
** pPager. 
................................................................................
*/
int sqlite3pager_pagecount(Pager *pPager){
  i64 n;
  assert( pPager!=0 );
  if( pPager->dbSize>=0 ){
    n = pPager->dbSize;
  } else {
    if( sqlite3OsFileSize(&pPager->fd, &n)!=SQLITE_OK ){
      pPager->errMask |= PAGER_ERR_DISK;
      return 0;
    }
    if( n>0 && n<pPager->pageSize ){
      n = 1;
    }else{
      n /= pPager->pageSize;
................................................................................
  assert( PAGER_SHARED==SHARED_LOCK );
  assert( PAGER_RESERVED==RESERVED_LOCK );
  assert( PAGER_EXCLUSIVE==EXCLUSIVE_LOCK );
  if( pPager->state>=locktype ){
    rc = SQLITE_OK;
  }else{
    do {
      rc = sqlite3OsLock(&pPager->fd, locktype);
    }while( rc==SQLITE_BUSY && sqlite3InvokeBusyHandler(pPager->pBusyHandler) );
    if( rc==SQLITE_OK ){
      pPager->state = locktype;
    }
  }
  return rc;
}
................................................................................
      ** operation. So disable IO error simulation so that testing
      ** works more easily.
      */
      disable_simulated_io_errors();
      sqlite3pager_rollback(pPager);
      enable_simulated_io_errors();
      if( !MEMDB ){
        sqlite3OsUnlock(&pPager->fd, NO_LOCK);
      }
      assert( pPager->errMask || pPager->journalOpen==0 );
      break;
    }
    case PAGER_SHARED: {
      if( !MEMDB ){
        sqlite3OsUnlock(&pPager->fd, NO_LOCK);
      }
      break;
    }
    default: {
      /* Do nothing */
      break;
    }
................................................................................
#endif
    pNext = pPg->pNextAll;
    sqliteFree(pPg);
  }
  TRACE2("CLOSE %d\n", PAGERID(pPager));
  assert( pPager->errMask || (pPager->journalOpen==0 && pPager->stmtOpen==0) );
  if( pPager->journalOpen ){
    sqlite3OsClose(&pPager->jfd);
  }
  sqliteFree(pPager->aInJournal);
  if( pPager->stmtOpen ){
    sqlite3OsClose(&pPager->stfd);
  }
  sqlite3OsClose(&pPager->fd);
  /* Temp files are automatically deleted by the OS
  ** if( pPager->tempFile ){
  **   sqlite3OsDelete(pPager->zFilename);
  ** }
  */

  sqliteFree(pPager);
  return SQLITE_OK;
}

................................................................................
      ** was turned off after the transaction was started.  Ticket #615 */
#ifndef NDEBUG
      {
        /* Make sure the pPager->nRec counter we are keeping agrees
        ** with the nRec computed from the size of the journal file.
        */
        i64 jSz;
        rc = sqlite3OsFileSize(&pPager->jfd, &jSz);
        if( rc!=0 ) return rc;
        assert( pPager->journalOff==jSz );
      }
#endif
      {
        /* Write the nRec value into the journal file header. If in
        ** full-synchronous mode, sync the journal first. This ensures that
        ** all data has really hit the disk before nRec is updated to mark
        ** it as a candidate for rollback. 
        */
        if( pPager->fullSync ){
          TRACE2("SYNC journal of %d\n", PAGERID(pPager));
          rc = sqlite3OsSync(&pPager->jfd, 0);
          if( rc!=0 ) return rc;
        }
        rc = sqlite3OsSeek(&pPager->jfd,
                           pPager->journalHdr + sizeof(aJournalMagic));
        if( rc ) return rc;
        rc = write32bits(&pPager->jfd, pPager->nRec);
        if( rc ) return rc;

        rc = sqlite3OsSeek(&pPager->jfd, pPager->journalOff);
        if( rc ) return rc;
      }
      TRACE2("SYNC journal of %d\n", PAGERID(pPager));
      rc = sqlite3OsSync(&pPager->jfd, pPager->fullSync);
      if( rc!=0 ) return rc;
      pPager->journalStarted = 1;
    }
    pPager->needSync = 0;

    /* Erase the needSync flag from every page.
    */
................................................................................
  int rc;

  if( pList==0 ) return SQLITE_OK;
  pPager = pList->pPager;

  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
  ** database file. If there is already an EXCLUSIVE lock, the following
  ** calls to sqlite3OsLock() are no-ops.
  **
  ** Moving the lock from RESERVED to EXCLUSIVE actually involves going
  ** through an intermediate state PENDING.   A PENDING lock prevents new
  ** readers from attaching to the database but is unsufficient for us to
  ** write.  The idea of a PENDING lock is to prevent new readers from
  ** coming in while we wait for existing readers to clear.
  **
................................................................................
  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
  if( rc!=SQLITE_OK ){
    return rc;
  }

  while( pList ){
    assert( pList->dirty );
    rc = sqlite3OsSeek(&pPager->fd, (pList->pgno-1)*(i64)pPager->pageSize);
    if( rc ) return rc;
    /* If there are dirty pages in the page cache with page numbers greater
    ** than Pager.dbSize, this means sqlite3pager_truncate() was called to
    ** make the file smaller (presumably by auto-vacuum code). Do not write
    ** any such pages to the file.
    */
    if( pList->pgno<=pPager->dbSize ){
      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 6);
      TRACE3("STORE %d page %d\n", PAGERID(pPager), pList->pgno);
      rc = sqlite3OsWrite(&pPager->fd, PGHDR_TO_DATA(pList), pPager->pageSize);

      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 0);
      TEST_INCR(pPager->nWrite);
    }
#ifndef NDEBUG
    else{
      TRACE3("NOSTORE %d page %d\n", PAGERID(pPager), pList->pgno);
    }
................................................................................
**
** If the current size of the database file is 0 but a journal file
** exists, that is probably an old journal left over from a prior
** database with the same name.  Just delete the journal.
*/
static int hasHotJournal(Pager *pPager){
  if( !pPager->useJournal ) return 0;
  if( !sqlite3OsFileExists(pPager->zJournal) ) return 0;
  if( sqlite3OsCheckReservedLock(&pPager->fd) ) return 0;
  if( sqlite3pager_pagecount(pPager)==0 ){
    sqlite3OsDelete(pPager->zJournal);
    return 0;
  }else{
    return 1;
  }
}

/*
................................................................................
       ** database is safe to read while this process is still rolling it 
       ** back.
       ** 
       ** Because the intermediate RESERVED lock is not requested, the
       ** second process will get to this point in the code and fail to
       ** obtain it's own EXCLUSIVE lock on the database file.
       */
       rc = sqlite3OsLock(&pPager->fd, EXCLUSIVE_LOCK);
       if( rc!=SQLITE_OK ){
         sqlite3OsUnlock(&pPager->fd, NO_LOCK);
         pPager->state = PAGER_UNLOCK;
         return rc;
       }
       pPager->state = PAGER_EXCLUSIVE;

       /* Open the journal for reading only.  Return SQLITE_BUSY if
       ** we are unable to open the journal file. 
       **
       ** The journal file does not need to be locked itself.  The
       ** journal file is never open unless the main database file holds
       ** a write lock, so there is never any chance of two or more
       ** processes opening the journal at the same time.
       */
       rc = sqlite3OsOpenReadOnly(pPager->zJournal, &pPager->jfd);
       if( rc!=SQLITE_OK ){
         sqlite3OsUnlock(&pPager->fd, NO_LOCK);
         pPager->state = PAGER_UNLOCK;
         return SQLITE_BUSY;
       }
       pPager->journalOpen = 1;
       pPager->journalStarted = 0;
       pPager->journalOff = 0;
       pPager->setMaster = 0;
................................................................................
      return rc;
    }
    if( sqlite3pager_pagecount(pPager)<(int)pgno ){
      memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
    }else{
      int rc;
      assert( MEMDB==0 );
      rc = sqlite3OsSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
      if( rc==SQLITE_OK ){
        rc = sqlite3OsRead(&pPager->fd, PGHDR_TO_DATA(pPg), pPager->pageSize);

      }
      TRACE3("FETCH %d page %d\n", PAGERID(pPager), pPg->pgno);
      CODEC(pPager, PGHDR_TO_DATA(pPg), pPg->pgno, 3);
      if( rc!=SQLITE_OK ){
        i64 fileSize;
        if( sqlite3OsFileSize(&pPager->fd,&fileSize)!=SQLITE_OK
               || fileSize>=pgno*pPager->pageSize ){
          sqlite3pager_unref(PGHDR_TO_DATA(pPg));
          return rc;
        }else{
          clear_simulated_io_error();
          memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
        }
................................................................................
  assert( pPager->aInJournal==0 );
  sqlite3pager_pagecount(pPager);
  pPager->aInJournal = sqliteMalloc( pPager->dbSize/8 + 1 );
  if( pPager->aInJournal==0 ){
    rc = SQLITE_NOMEM;
    goto failed_to_open_journal;
  }
  rc = sqlite3OsOpenExclusive(pPager->zJournal, &pPager->jfd,pPager->tempFile);

  pPager->journalOff = 0;
  pPager->setMaster = 0;
  pPager->journalHdr = 0;
  if( rc!=SQLITE_OK ){
    goto failed_to_open_journal;
  }
  SET_FULLSYNC(pPager->jfd, pPager->fullSync);
  SET_FULLSYNC(pPager->fd, pPager->fullSync);
  sqlite3OsOpenDirectory(pPager->zDirectory, &pPager->jfd);
  pPager->journalOpen = 1;
  pPager->journalStarted = 0;
  pPager->needSync = 0;
  pPager->alwaysRollback = 0;
  pPager->nRec = 0;
  if( pPager->errMask!=0 ){
    rc = pager_errcode(pPager);
................................................................................
    }
  }
  return rc;

failed_to_open_journal:
  sqliteFree(pPager->aInJournal);
  pPager->aInJournal = 0;
  sqlite3OsUnlock(&pPager->fd, NO_LOCK);
  pPager->state = PAGER_UNLOCK;
  return rc;
}

/*
** Acquire a write-lock on the database.  The lock is removed when
** the any of the following happen:
................................................................................
  assert( pPager->state!=PAGER_UNLOCK );
  if( pPager->state==PAGER_SHARED ){
    assert( pPager->aInJournal==0 );
    if( MEMDB ){
      pPager->state = PAGER_EXCLUSIVE;
      pPager->origDbSize = pPager->dbSize;
    }else{
      rc = sqlite3OsLock(&pPager->fd, RESERVED_LOCK);
      if( rc==SQLITE_OK ){
        pPager->state = PAGER_RESERVED;
        if( exFlag ){
          rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
        }
      }
      if( rc!=SQLITE_OK ){
................................................................................
          assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
          CODEC(pPager, pData, pPg->pgno, 7);
          cksum = pager_cksum(pPager, pPg->pgno, pData);
          saved = *(u32*)PGHDR_TO_EXTRA(pPg, pPager);
          store32bits(cksum, pPg, pPager->pageSize);
          szPg = pPager->pageSize+8;
          store32bits(pPg->pgno, pPg, -4);
          rc = sqlite3OsWrite(&pPager->jfd, &((char*)pData)[-4], szPg);
          pPager->journalOff += szPg;
          TRACE4("JOURNAL %d page %d needSync=%d\n",
                  PAGERID(pPager), pPg->pgno, pPg->needSync);
          CODEC(pPager, pData, pPg->pgno, 0);
          *(u32*)PGHDR_TO_EXTRA(pPg, pPager) = saved;
          if( rc!=SQLITE_OK ){
            sqlite3pager_rollback(pPager);
................................................................................
        if( pHist->pStmt ){
          memcpy(pHist->pStmt, PGHDR_TO_DATA(pPg), pPager->pageSize);
        }
        TRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
      }else{
        store32bits(pPg->pgno, pPg, -4);
        CODEC(pPager, pData, pPg->pgno, 7);
        rc = sqlite3OsWrite(&pPager->stfd,((char*)pData)-4, pPager->pageSize+4);

        TRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
        CODEC(pPager, pData, pPg->pgno, 0);
        if( rc!=SQLITE_OK ){
          sqlite3pager_rollback(pPager);
          pPager->errMask |= PAGER_ERR_FULL;
          return rc;
        }
................................................................................
    }
#endif
    pPager->pStmt = 0;
    pPager->state = PAGER_SHARED;
    return SQLITE_OK;
  }
  if( pPager->dirtyCache==0 ){
    /* Exit early (without doing the time-consuming sqlite3OsSync() calls)
    ** if there have been no changes to the database file. */
    assert( pPager->needSync==0 );
    rc = pager_unwritelock(pPager);
    pPager->dbSize = -1;
    return rc;
  }
  assert( pPager->journalOpen );
................................................................................
  if( !pPager->journalOpen ){
    pPager->stmtAutoopen = 1;
    return SQLITE_OK;
  }
  assert( pPager->journalOpen );
  pPager->aInStmt = sqliteMalloc( pPager->dbSize/8 + 1 );
  if( pPager->aInStmt==0 ){
    sqlite3OsLock(&pPager->fd, SHARED_LOCK);
    return SQLITE_NOMEM;
  }
#ifndef NDEBUG
  rc = sqlite3OsFileSize(&pPager->jfd, &pPager->stmtJSize);
  if( rc ) goto stmt_begin_failed;
  assert( pPager->stmtJSize == pPager->journalOff );
#endif
  pPager->stmtJSize = pPager->journalOff;
  pPager->stmtSize = pPager->dbSize;
  pPager->stmtHdrOff = 0;
  pPager->stmtCksum = pPager->cksumInit;
................................................................................
** Commit a statement.
*/
int sqlite3pager_stmt_commit(Pager *pPager){
  if( pPager->stmtInUse ){
    PgHdr *pPg, *pNext;
    TRACE2("STMT-COMMIT %d\n", PAGERID(pPager));
    if( !MEMDB ){
      sqlite3OsSeek(&pPager->stfd, 0);
      /* sqlite3OsTruncate(&pPager->stfd, 0); */
      sqliteFree( pPager->aInStmt );
      pPager->aInStmt = 0;
    }
    for(pPg=pPager->pStmt; pPg; pPg=pNext){
      pNext = pPg->pNextStmt;
      assert( pPg->inStmt );
      pPg->inStmt = 0;
................................................................................
    /* Write all dirty pages to the database file */
    pPg = pager_get_all_dirty_pages(pPager);
    rc = pager_write_pagelist(pPg);
    if( rc!=SQLITE_OK ) goto sync_exit;

    /* Sync the database file. */
    if( !pPager->noSync ){
      rc = sqlite3OsSync(&pPager->fd, 0);
    }

    pPager->state = PAGER_SYNCED;
  }

sync_exit:
  return rc;







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....
1168
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1177
1178
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....
1201
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....
1269
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....
1330
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1342
1343
1344
....
1403
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1412
1413
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1415
1416
1417
....
1429
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1438
1439
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1441
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1443
....
1451
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1461
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1463
1464
1465
....
1511
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1515
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1523
1524
1525
....
1562
1563
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1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
....
1615
1616
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1622
1623
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1650
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1652
1653
1654
....
1656
1657
1658
1659
1660
1661
1662



1663
1664
1665
1666
1667
1668
1669
....
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
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1777
1778
1779
1780
1781
....
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
....
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
....
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
....
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
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2029
2030
2031
2032
2033
2034
2035
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2037
2038
2039
2040
2041
....
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
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2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
....
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
....
2227
2228
2229
2230
2231
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2233
2234
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2236
2237
2238
2239
2240
2241
2242
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2246
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2249
2250
2251
2252
....
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
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2295
2296
2297
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....
2364
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....
2539
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....
2670
2671
2672
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....
2708
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2713
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....
2752
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2755
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2757
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2764
2765
2766
....
2863
2864
2865
2866
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2870
2871
2872
2873
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2877
....
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
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2926
2927
....
3116
3117
3118
3119
3120
3121
3122
3123
3124
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3128
3129
3130
....
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
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3293
....
3312
3313
3314
3315
3316
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3318
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3320
3321
3322
3323
3324
3325
3326
3327
....
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.218 2005/11/26 00:25:03 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>
................................................................................
** error code is something goes wrong.
**
** All values are stored on disk as big-endian.
*/
static int read32bits(OsFile *fd, u32 *pRes){
  u32 res;
  int rc;
  rc = sqlite3Io.xRead(fd, &res, sizeof(res));
  if( rc==SQLITE_OK ){
    unsigned char ac[4];
    memcpy(ac, &res, 4);
    res = (ac[0]<<24) | (ac[1]<<16) | (ac[2]<<8) | ac[3];
  }
  *pRes = res;
  return rc;
................................................................................
*/
static int write32bits(OsFile *fd, u32 val){
  unsigned char ac[4];
  ac[0] = (val>>24) & 0xff;
  ac[1] = (val>>16) & 0xff;
  ac[2] = (val>>8) & 0xff;
  ac[3] = val & 0xff;
  return sqlite3Io.xWrite(fd, ac, 4);
}

/*
** Write the 32-bit integer 'val' into the page identified by page header
** 'p' at offset 'offset'.
*/
static void store32bits(u32 val, PgHdr *p, int offset){
................................................................................
  i64 szJ;
  u32 cksum;
  int i;
  unsigned char aMagic[8]; /* A buffer to hold the magic header */

  *pzMaster = 0;

  rc = sqlite3Io.xFileSize(pJrnl, &szJ);
  if( rc!=SQLITE_OK || szJ<16 ) return rc;

  rc = sqlite3Io.xSeek(pJrnl, szJ-16);
  if( rc!=SQLITE_OK ) return rc;
 
  rc = read32bits(pJrnl, &len);
  if( rc!=SQLITE_OK ) return rc;

  rc = read32bits(pJrnl, &cksum);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3Io.xRead(pJrnl, aMagic, 8);
  if( rc!=SQLITE_OK || memcmp(aMagic, aJournalMagic, 8) ) return rc;

  rc = sqlite3Io.xSeek(pJrnl, szJ-16-len);
  if( rc!=SQLITE_OK ) return rc;

  *pzMaster = (char *)sqliteMalloc(len+1);
  if( !*pzMaster ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3Io.xRead(pJrnl, *pzMaster, len);
  if( rc!=SQLITE_OK ){
    sqliteFree(*pzMaster);
    *pzMaster = 0;
    return rc;
  }

  /* See if the checksum matches the master journal name */
................................................................................
  if( c ){
    offset = ((c-1)/JOURNAL_HDR_SZ(pPager) + 1) * JOURNAL_HDR_SZ(pPager);
  }
  assert( offset%JOURNAL_HDR_SZ(pPager)==0 );
  assert( offset>=c );
  assert( (offset-c)<JOURNAL_HDR_SZ(pPager) );
  pPager->journalOff = offset;
  return sqlite3Io.xSeek(&pPager->jfd, pPager->journalOff);
}

/*
** The journal file must be open when this routine is called. A journal
** header (JOURNAL_HDR_SZ bytes) is written into the journal file at the
** current location.
**
................................................................................
  **
  ** Possibly for a pager not in no-sync mode, the journal magic should not
  ** be written until nRec is filled in as part of next syncJournal(). 
  **
  ** Actually maybe the whole journal header should be delayed until that
  ** point. Think about this.
  */
  rc = sqlite3Io.xWrite(&pPager->jfd, aJournalMagic, sizeof(aJournalMagic));

  if( rc==SQLITE_OK ){
    /* The nRec Field. 0xFFFFFFFF for no-sync journals. */
    rc = write32bits(&pPager->jfd, pPager->noSync ? 0xffffffff : 0);
  }
  if( rc==SQLITE_OK ){
    /* The random check-hash initialiser */ 
................................................................................
    rc = write32bits(&pPager->jfd, pPager->sectorSize);
  }

  /* The journal header has been written successfully. Seek the journal
  ** file descriptor to the end of the journal header sector.
  */
  if( rc==SQLITE_OK ){
    rc = sqlite3Io.xSeek(&pPager->jfd, pPager->journalOff-1);
    if( rc==SQLITE_OK ){
      rc = sqlite3Io.xWrite(&pPager->jfd, "\000", 1);
    }
  }
  return rc;
}

/*
** The journal file must be open when this is called. A journal header file
................................................................................
  rc = seekJournalHdr(pPager);
  if( rc ) return rc;

  if( pPager->journalOff+JOURNAL_HDR_SZ(pPager) > journalSize ){
    return SQLITE_DONE;
  }

  rc = sqlite3Io.xRead(&pPager->jfd, aMagic, sizeof(aMagic));
  if( rc ) return rc;

  if( memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
    return SQLITE_DONE;
  }

  rc = read32bits(&pPager->jfd, pNRec);
................................................................................
  ** is being called from within pager_playback(). The local value
  ** of Pager.sectorSize is restored at the end of that routine.
  */
  rc = read32bits(&pPager->jfd, (u32 *)&pPager->sectorSize);
  if( rc ) return rc;

  pPager->journalOff += JOURNAL_HDR_SZ(pPager);
  rc = sqlite3Io.xSeek(&pPager->jfd, pPager->journalOff);
  return rc;
}


/*
** Write the supplied master journal name into the journal file for pager
** pPager at the current location. The master journal name must be the last
................................................................................
    if( rc!=SQLITE_OK ) return rc;
  }
  pPager->journalOff += (len+20);

  rc = write32bits(&pPager->jfd, PAGER_MJ_PGNO(pPager));
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3Io.xWrite(&pPager->jfd, zMaster, len);
  if( rc!=SQLITE_OK ) return rc;

  rc = write32bits(&pPager->jfd, len);
  if( rc!=SQLITE_OK ) return rc;

  rc = write32bits(&pPager->jfd, cksum);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3Io.xWrite(&pPager->jfd, aJournalMagic, sizeof(aJournalMagic));
  pPager->needSync = !pPager->noSync;
  return rc;
}

/*
** Add or remove a page from the list of all pages that are in the
** statement journal.
................................................................................
  pPager->pLast = 0;
  pPager->pAll = 0;
  memset(pPager->aHash, 0, sizeof(pPager->aHash));
  pPager->nPage = 0;
  if( pPager->state>=PAGER_RESERVED ){
    sqlite3pager_rollback(pPager);
  }
  sqlite3Io.xUnlock(&pPager->fd, NO_LOCK);
  pPager->state = PAGER_UNLOCK;
  pPager->dbSize = -1;
  pPager->nRef = 0;
  assert( pPager->journalOpen==0 );
}

/*
................................................................................
  int rc;
  assert( !MEMDB );
  if( pPager->state<PAGER_RESERVED ){
    return SQLITE_OK;
  }
  sqlite3pager_stmt_commit(pPager);
  if( pPager->stmtOpen ){
    sqlite3Io.xClose(&pPager->stfd);
    pPager->stmtOpen = 0;
  }
  if( pPager->journalOpen ){
    sqlite3Io.xClose(&pPager->jfd);
    pPager->journalOpen = 0;
    sqlite3Io.xDelete(pPager->zJournal);
    sqliteFree( pPager->aInJournal );
    pPager->aInJournal = 0;
    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
      pPg->inJournal = 0;
      pPg->dirty = 0;
      pPg->needSync = 0;
#ifdef SQLITE_CHECK_PAGES
................................................................................
    }
    pPager->dirtyCache = 0;
    pPager->nRec = 0;
  }else{
    assert( pPager->aInJournal==0 );
    assert( pPager->dirtyCache==0 || pPager->useJournal==0 );
  }
  rc = sqlite3Io.xUnlock(&pPager->fd, SHARED_LOCK);
  pPager->state = PAGER_SHARED;
  pPager->origDbSize = 0;
  pPager->setMaster = 0;
  return rc;
}

/*
................................................................................
  ** statement journals.  Verify that this is always the case
  */
  assert( jfd == (useCksum ? &pPager->jfd : &pPager->stfd) );


  rc = read32bits(jfd, &pgno);
  if( rc!=SQLITE_OK ) return rc;
  rc = sqlite3Io.xRead(jfd, &aData, pPager->pageSize);
  if( rc!=SQLITE_OK ) return rc;
  pPager->journalOff += pPager->pageSize + 4;

  /* Sanity checking on the page.  This is more important that I originally
  ** thought.  If a power failure occurs while the journal is being written,
  ** it could cause invalid data to be written into the journal.  We need to
  ** detect this invalid data (with high probability) and ignore it.
................................................................................
  ** page content is in the main journal either because the page is not in
  ** cache or else it is marked as needSync==0.
  */
  pPg = pager_lookup(pPager, pgno);
  assert( pPager->state>=PAGER_EXCLUSIVE || pPg!=0 );
  TRACE3("PLAYBACK %d page %d\n", PAGERID(pPager), pgno);
  if( pPager->state>=PAGER_EXCLUSIVE && (pPg==0 || pPg->needSync==0) ){
    rc = sqlite3Io.xSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
    if( rc==SQLITE_OK ){
      rc = sqlite3Io.xWrite(&pPager->fd, aData, pPager->pageSize);
    }
    if( pPg ) pPg->dirty = 0;
  }
  if( pPg ){
    /* No page should ever be explicitly rolled back that is in use, except
    ** for page 1 which is held in use in order to keep the lock on the
    ** database active. However such a page may be rolled back as a result
................................................................................
  char *zMasterJournal = 0; /* Contents of master journal file */
  i64 nMasterJournal;       /* Size of master journal file */

  /* Open the master journal file exclusively in case some other process
  ** is running this routine also. Not that it makes too much difference.
  */
  memset(&master, 0, sizeof(master));
  rc = sqlite3Io.xOpenReadOnly(zMaster, &master);
  if( rc!=SQLITE_OK ) goto delmaster_out;
  master_open = 1;
  rc = sqlite3Io.xFileSize(&master, &nMasterJournal);
  if( rc!=SQLITE_OK ) goto delmaster_out;

  if( nMasterJournal>0 ){
    char *zJournal;
    char *zMasterPtr = 0;

    /* Load the entire master journal file into space obtained from
................................................................................
    ** sqliteMalloc() and pointed to by zMasterJournal. 
    */
    zMasterJournal = (char *)sqliteMalloc(nMasterJournal);
    if( !zMasterJournal ){
      rc = SQLITE_NOMEM;
      goto delmaster_out;
    }
    rc = sqlite3Io.xRead(&master, zMasterJournal, nMasterJournal);
    if( rc!=SQLITE_OK ) goto delmaster_out;

    zJournal = zMasterJournal;
    while( (zJournal-zMasterJournal)<nMasterJournal ){
      if( sqlite3Io.xFileExists(zJournal) ){
        /* One of the journals pointed to by the master journal exists.
        ** Open it and check if it points at the master journal. If
        ** so, return without deleting the master journal file.
        */
        OsFile journal;
        int c;

        memset(&journal, 0, sizeof(journal));
        rc = sqlite3Io.xOpenReadOnly(zJournal, &journal);
        if( rc!=SQLITE_OK ){
          goto delmaster_out;
        }

        rc = readMasterJournal(&journal, &zMasterPtr);
        sqlite3Io.xClose(&journal);
        if( rc!=SQLITE_OK ){
          goto delmaster_out;
        }

        c = zMasterPtr!=0 && strcmp(zMasterPtr, zMaster)==0;
        sqliteFree(zMasterPtr);
        if( c ){
................................................................................
          goto delmaster_out;
        }
      }
      zJournal += (strlen(zJournal)+1);
    }
  }
  
  sqlite3Io.xDelete(zMaster);

delmaster_out:
  if( zMasterJournal ){
    sqliteFree(zMasterJournal);
  }  
  if( master_open ){
    sqlite3Io.xClose(&master);
  }
  return rc;
}

/*
** Make every page in the cache agree with what is on disk.  In other words,
** reread the disk to reset the state of the cache.
................................................................................
static int pager_reload_cache(Pager *pPager){
  PgHdr *pPg;
  int rc = SQLITE_OK;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    char zBuf[SQLITE_MAX_PAGE_SIZE];
    if( !pPg->dirty ) continue;
    if( (int)pPg->pgno <= pPager->origDbSize ){
      rc = sqlite3Io.xSeek(&pPager->fd, pPager->pageSize*(i64)(pPg->pgno-1));
      if( rc==SQLITE_OK ){
        rc = sqlite3Io.xRead(&pPager->fd, zBuf, pPager->pageSize);
      }
      TRACE3("REFETCH %d page %d\n", PAGERID(pPager), pPg->pgno);
      if( rc ) break;
      CODEC(pPager, zBuf, pPg->pgno, 2);
    }else{
      memset(zBuf, 0, pPager->pageSize);
    }
................................................................................

/*
** Truncate the main file of the given pager to the number of pages
** indicated.
*/
static int pager_truncate(Pager *pPager, int nPage){
  assert( pPager->state>=PAGER_EXCLUSIVE );
  return sqlite3Io.xTruncate(&pPager->fd, pPager->pageSize*(i64)nPage);
}

/*
** Playback the journal and thus restore the database file to
** the state it was in before we started making changes.  
**
** The journal file format is as follows: 
................................................................................
  int rc;                  /* Result code of a subroutine */
  char *zMaster = 0;       /* Name of master journal file if any */

  /* Figure out how many records are in the journal.  Abort early if
  ** the journal is empty.
  */
  assert( pPager->journalOpen );
  rc = sqlite3Io.xFileSize(&pPager->jfd, &szJ);
  if( rc!=SQLITE_OK ){
    goto end_playback;
  }

  /* Read the master journal name from the journal, if it is present.
  ** If a master journal file name is specified, but the file is not
  ** present on disk, then the journal is not hot and does not need to be
  ** played back.
  */
  rc = readMasterJournal(&pPager->jfd, &zMaster);
  assert( rc!=SQLITE_DONE );
  if( rc!=SQLITE_OK || (zMaster && !sqlite3Io.xFileExists(zMaster)) ){
    sqliteFree(zMaster);
    zMaster = 0;
    if( rc==SQLITE_DONE ) rc = SQLITE_OK;
    goto end_playback;
  }
  sqlite3Io.xSeek(&pPager->jfd, 0);
  pPager->journalOff = 0;

  /* This loop terminates either when the readJournalHdr() call returns
  ** SQLITE_DONE or an IO error occurs. */
  while( 1 ){

    /* Read the next journal header from the journal file.  If there are
................................................................................
      rc = pager_truncate(pPager, mxPg);
      if( rc!=SQLITE_OK ){
        goto end_playback;
      }
      pPager->dbSize = mxPg;
    }

    /* rc = sqlite3Io.xSeek(&pPager->jfd, JOURNAL_HDR_SZ(pPager)); */
    if( rc!=SQLITE_OK ) goto end_playback;
  
    /* Copy original pages out of the journal and back into the database file.
    */
    for(i=0; i<nRec; i++){
      rc = pager_playback_one_page(pPager, &pPager->jfd, 1);
      if( rc!=SQLITE_OK ){
................................................................................
  int i;                   /* Loop counter */
  int rc;

  szJ = pPager->journalOff;
#ifndef NDEBUG 
  {
    i64 os_szJ;
    rc = sqlite3Io.xFileSize(&pPager->jfd, &os_szJ);
    if( rc!=SQLITE_OK ) return rc;
    assert( szJ==os_szJ );
  }
#endif

  /* Set hdrOff to be the offset to the first journal header written
  ** this statement transaction, or the end of the file if no journal
................................................................................
    rc = pager_truncate(pPager, pPager->stmtSize);
  }
  pPager->dbSize = pPager->stmtSize;

  /* Figure out how many records are in the statement journal.
  */
  assert( pPager->stmtInUse && pPager->journalOpen );
  sqlite3Io.xSeek(&pPager->stfd, 0);
  nRec = pPager->stmtNRec;
  
  /* Copy original pages out of the statement journal and back into the
  ** database file.  Note that the statement journal omits checksums from
  ** each record since power-failure recovery is not important to statement
  ** journals.
  */
................................................................................
  ** was the size of the journal file when this statement was started, so
  ** everything after that needs to be rolled back, either into the
  ** database, the memory cache, or both.
  **
  ** If it is not zero, then Pager.stmtHdrOff is the offset to the start
  ** of the first journal header written during this statement transaction.
  */
  rc = sqlite3Io.xSeek(&pPager->jfd, pPager->stmtJSize);
  if( rc!=SQLITE_OK ){
    goto end_stmt_playback;
  }
  pPager->journalOff = pPager->stmtJSize;
  pPager->cksumInit = pPager->stmtCksum;
  assert( JOURNAL_HDR_SZ(pPager)<(pPager->pageSize+8) );
  while( pPager->journalOff <= (hdrOff-(pPager->pageSize+8)) ){
................................................................................
}

/*
** Adjust the robustness of the database to damage due to OS crashes
** or power failures by changing the number of syncs()s when writing
** the rollback journal.  There are three levels:
**
**    OFF       sqlite3Io.xSync() is never called.  This is the default
**              for temporary and transient files.
**
**    NORMAL    The journal is synced once before writes begin on the
**              database.  This is normally adequate protection, but
**              it is theoretically possible, though very unlikely,
**              that an inopertune power failure could leave the journal
**              in a state which would cause damage to the database
................................................................................
*/
static int sqlite3pager_opentemp(char *zFile, OsFile *fd){
  int cnt = 8;
  int rc;
  sqlite3_opentemp_count++;  /* Used for testing and analysis only */
  do{
    cnt--;
    sqlite3Io.xTempFileName(zFile);
    rc = sqlite3Io.xOpenExclusive(zFile, fd, 1);
  }while( cnt>0 && rc!=SQLITE_OK && rc!=SQLITE_NOMEM );
  return rc;
}

/*
** Create a new page cache and put a pointer to the page cache in *ppPager.
** The file to be cached need not exist.  The file is not locked until
................................................................................
    if( strcmp(zFilename,":memory:")==0 ){
      memDb = 1;
      zFullPathname = sqliteStrDup("");
      rc = SQLITE_OK;
    }else
#endif
    {
      zFullPathname = sqlite3Io.xFullPathname(zFilename);
      if( zFullPathname ){
        rc = sqlite3Io.xOpenReadWrite(zFullPathname, &fd, &readOnly);
      }
    }
  }else{
    rc = sqlite3pager_opentemp(zTemp, &fd);
    zFilename = zTemp;
    zFullPathname = sqlite3Io.xFullPathname(zFilename);
    if( rc==SQLITE_OK ){
      tempFile = 1;
    }
  }
  if( !zFullPathname ){
    sqlite3Io.xClose(&fd);
    return SQLITE_NOMEM;
  }
  if( rc!=SQLITE_OK ){
    sqlite3Io.xClose(&fd);
    sqliteFree(zFullPathname);
    return rc;
  }
  nameLen = strlen(zFullPathname);
  pPager = sqliteMalloc( sizeof(*pPager) + nameLen*3 + 30 );
  if( pPager==0 ){
    sqlite3Io.xClose(&fd);
    sqliteFree(zFullPathname);
    return SQLITE_NOMEM;
  }
  TRACE3("OPEN %d %s\n", FILEHANDLEID(fd), zFullPathname);
  pPager->zFilename = (char*)&pPager[1];
  pPager->zDirectory = &pPager->zFilename[nameLen+1];
  pPager->zJournal = &pPager->zDirectory[nameLen+1];
................................................................................
  strcpy(pPager->zDirectory, zFullPathname);
  for(i=nameLen; i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;
  strcpy(pPager->zJournal, zFullPathname);
  sqliteFree(zFullPathname);
  strcpy(&pPager->zJournal[nameLen], "-journal");
  pPager->fd = fd;



  pPager->journalOpen = 0;
  pPager->useJournal = useJournal && !memDb;
  pPager->noReadlock = noReadlock && readOnly;
  pPager->stmtOpen = 0;
  pPager->stmtInUse = 0;
  pPager->nRef = 0;
  pPager->dbSize = memDb-1;
................................................................................
/*
** Read the first N bytes from the beginning of the file into memory
** that pDest points to.  No error checking is done.
*/
void sqlite3pager_read_fileheader(Pager *pPager, int N, unsigned char *pDest){
  memset(pDest, 0, N);
  if( MEMDB==0 ){
    sqlite3Io.xSeek(&pPager->fd, 0);
    sqlite3Io.xRead(&pPager->fd, pDest, N);
    clear_simulated_io_error();
  }
}

/*
** Return the total number of pages in the disk file associated with
** pPager. 
................................................................................
*/
int sqlite3pager_pagecount(Pager *pPager){
  i64 n;
  assert( pPager!=0 );
  if( pPager->dbSize>=0 ){
    n = pPager->dbSize;
  } else {
    if( sqlite3Io.xFileSize(&pPager->fd, &n)!=SQLITE_OK ){
      pPager->errMask |= PAGER_ERR_DISK;
      return 0;
    }
    if( n>0 && n<pPager->pageSize ){
      n = 1;
    }else{
      n /= pPager->pageSize;
................................................................................
  assert( PAGER_SHARED==SHARED_LOCK );
  assert( PAGER_RESERVED==RESERVED_LOCK );
  assert( PAGER_EXCLUSIVE==EXCLUSIVE_LOCK );
  if( pPager->state>=locktype ){
    rc = SQLITE_OK;
  }else{
    do {
      rc = sqlite3Io.xLock(&pPager->fd, locktype);
    }while( rc==SQLITE_BUSY && sqlite3InvokeBusyHandler(pPager->pBusyHandler) );
    if( rc==SQLITE_OK ){
      pPager->state = locktype;
    }
  }
  return rc;
}
................................................................................
      ** operation. So disable IO error simulation so that testing
      ** works more easily.
      */
      disable_simulated_io_errors();
      sqlite3pager_rollback(pPager);
      enable_simulated_io_errors();
      if( !MEMDB ){
        sqlite3Io.xUnlock(&pPager->fd, NO_LOCK);
      }
      assert( pPager->errMask || pPager->journalOpen==0 );
      break;
    }
    case PAGER_SHARED: {
      if( !MEMDB ){
        sqlite3Io.xUnlock(&pPager->fd, NO_LOCK);
      }
      break;
    }
    default: {
      /* Do nothing */
      break;
    }
................................................................................
#endif
    pNext = pPg->pNextAll;
    sqliteFree(pPg);
  }
  TRACE2("CLOSE %d\n", PAGERID(pPager));
  assert( pPager->errMask || (pPager->journalOpen==0 && pPager->stmtOpen==0) );
  if( pPager->journalOpen ){
    sqlite3Io.xClose(&pPager->jfd);
  }
  sqliteFree(pPager->aInJournal);
  if( pPager->stmtOpen ){
    sqlite3Io.xClose(&pPager->stfd);
  }
  sqlite3Io.xClose(&pPager->fd);
  /* Temp files are automatically deleted by the OS
  ** if( pPager->tempFile ){
  **   sqlite3Io.xDelete(pPager->zFilename);
  ** }
  */

  sqliteFree(pPager);
  return SQLITE_OK;
}

................................................................................
      ** was turned off after the transaction was started.  Ticket #615 */
#ifndef NDEBUG
      {
        /* Make sure the pPager->nRec counter we are keeping agrees
        ** with the nRec computed from the size of the journal file.
        */
        i64 jSz;
        rc = sqlite3Io.xFileSize(&pPager->jfd, &jSz);
        if( rc!=0 ) return rc;
        assert( pPager->journalOff==jSz );
      }
#endif
      {
        /* Write the nRec value into the journal file header. If in
        ** full-synchronous mode, sync the journal first. This ensures that
        ** all data has really hit the disk before nRec is updated to mark
        ** it as a candidate for rollback. 
        */
        if( pPager->fullSync ){
          TRACE2("SYNC journal of %d\n", PAGERID(pPager));
          rc = sqlite3Io.xSync(&pPager->jfd, 0);
          if( rc!=0 ) return rc;
        }
        rc = sqlite3Io.xSeek(&pPager->jfd,
                           pPager->journalHdr + sizeof(aJournalMagic));
        if( rc ) return rc;
        rc = write32bits(&pPager->jfd, pPager->nRec);
        if( rc ) return rc;

        rc = sqlite3Io.xSeek(&pPager->jfd, pPager->journalOff);
        if( rc ) return rc;
      }
      TRACE2("SYNC journal of %d\n", PAGERID(pPager));
      rc = sqlite3Io.xSync(&pPager->jfd, pPager->fullSync);
      if( rc!=0 ) return rc;
      pPager->journalStarted = 1;
    }
    pPager->needSync = 0;

    /* Erase the needSync flag from every page.
    */
................................................................................
  int rc;

  if( pList==0 ) return SQLITE_OK;
  pPager = pList->pPager;

  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
  ** database file. If there is already an EXCLUSIVE lock, the following
  ** calls to sqlite3Io.xLock() are no-ops.
  **
  ** Moving the lock from RESERVED to EXCLUSIVE actually involves going
  ** through an intermediate state PENDING.   A PENDING lock prevents new
  ** readers from attaching to the database but is unsufficient for us to
  ** write.  The idea of a PENDING lock is to prevent new readers from
  ** coming in while we wait for existing readers to clear.
  **
................................................................................
  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
  if( rc!=SQLITE_OK ){
    return rc;
  }

  while( pList ){
    assert( pList->dirty );
    rc = sqlite3Io.xSeek(&pPager->fd, (pList->pgno-1)*(i64)pPager->pageSize);
    if( rc ) return rc;
    /* If there are dirty pages in the page cache with page numbers greater
    ** than Pager.dbSize, this means sqlite3pager_truncate() was called to
    ** make the file smaller (presumably by auto-vacuum code). Do not write
    ** any such pages to the file.
    */
    if( pList->pgno<=pPager->dbSize ){
      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 6);
      TRACE3("STORE %d page %d\n", PAGERID(pPager), pList->pgno);
      rc = sqlite3Io.xWrite(&pPager->fd, PGHDR_TO_DATA(pList),
                             pPager->pageSize);
      CODEC(pPager, PGHDR_TO_DATA(pList), pList->pgno, 0);
      TEST_INCR(pPager->nWrite);
    }
#ifndef NDEBUG
    else{
      TRACE3("NOSTORE %d page %d\n", PAGERID(pPager), pList->pgno);
    }
................................................................................
**
** If the current size of the database file is 0 but a journal file
** exists, that is probably an old journal left over from a prior
** database with the same name.  Just delete the journal.
*/
static int hasHotJournal(Pager *pPager){
  if( !pPager->useJournal ) return 0;
  if( !sqlite3Io.xFileExists(pPager->zJournal) ) return 0;
  if( sqlite3Io.xCheckReservedLock(&pPager->fd) ) return 0;
  if( sqlite3pager_pagecount(pPager)==0 ){
    sqlite3Io.xDelete(pPager->zJournal);
    return 0;
  }else{
    return 1;
  }
}

/*
................................................................................
       ** database is safe to read while this process is still rolling it 
       ** back.
       ** 
       ** Because the intermediate RESERVED lock is not requested, the
       ** second process will get to this point in the code and fail to
       ** obtain it's own EXCLUSIVE lock on the database file.
       */
       rc = sqlite3Io.xLock(&pPager->fd, EXCLUSIVE_LOCK);
       if( rc!=SQLITE_OK ){
         sqlite3Io.xUnlock(&pPager->fd, NO_LOCK);
         pPager->state = PAGER_UNLOCK;
         return rc;
       }
       pPager->state = PAGER_EXCLUSIVE;

       /* Open the journal for reading only.  Return SQLITE_BUSY if
       ** we are unable to open the journal file. 
       **
       ** The journal file does not need to be locked itself.  The
       ** journal file is never open unless the main database file holds
       ** a write lock, so there is never any chance of two or more
       ** processes opening the journal at the same time.
       */
       rc = sqlite3Io.xOpenReadOnly(pPager->zJournal, &pPager->jfd);
       if( rc!=SQLITE_OK ){
         sqlite3Io.xUnlock(&pPager->fd, NO_LOCK);
         pPager->state = PAGER_UNLOCK;
         return SQLITE_BUSY;
       }
       pPager->journalOpen = 1;
       pPager->journalStarted = 0;
       pPager->journalOff = 0;
       pPager->setMaster = 0;
................................................................................
      return rc;
    }
    if( sqlite3pager_pagecount(pPager)<(int)pgno ){
      memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
    }else{
      int rc;
      assert( MEMDB==0 );
      rc = sqlite3Io.xSeek(&pPager->fd, (pgno-1)*(i64)pPager->pageSize);
      if( rc==SQLITE_OK ){
        rc = sqlite3Io.xRead(&pPager->fd, PGHDR_TO_DATA(pPg),
                              pPager->pageSize);
      }
      TRACE3("FETCH %d page %d\n", PAGERID(pPager), pPg->pgno);
      CODEC(pPager, PGHDR_TO_DATA(pPg), pPg->pgno, 3);
      if( rc!=SQLITE_OK ){
        i64 fileSize;
        if( sqlite3Io.xFileSize(&pPager->fd,&fileSize)!=SQLITE_OK
               || fileSize>=pgno*pPager->pageSize ){
          sqlite3pager_unref(PGHDR_TO_DATA(pPg));
          return rc;
        }else{
          clear_simulated_io_error();
          memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
        }
................................................................................
  assert( pPager->aInJournal==0 );
  sqlite3pager_pagecount(pPager);
  pPager->aInJournal = sqliteMalloc( pPager->dbSize/8 + 1 );
  if( pPager->aInJournal==0 ){
    rc = SQLITE_NOMEM;
    goto failed_to_open_journal;
  }
  rc = sqlite3Io.xOpenExclusive(pPager->zJournal, &pPager->jfd,
                                 pPager->tempFile);
  pPager->journalOff = 0;
  pPager->setMaster = 0;
  pPager->journalHdr = 0;
  if( rc!=SQLITE_OK ){
    goto failed_to_open_journal;
  }
  SET_FULLSYNC(pPager->jfd, pPager->fullSync);
  SET_FULLSYNC(pPager->fd, pPager->fullSync);
  sqlite3Io.xOpenDirectory(pPager->zDirectory, &pPager->jfd);
  pPager->journalOpen = 1;
  pPager->journalStarted = 0;
  pPager->needSync = 0;
  pPager->alwaysRollback = 0;
  pPager->nRec = 0;
  if( pPager->errMask!=0 ){
    rc = pager_errcode(pPager);
................................................................................
    }
  }
  return rc;

failed_to_open_journal:
  sqliteFree(pPager->aInJournal);
  pPager->aInJournal = 0;
  sqlite3Io.xUnlock(&pPager->fd, NO_LOCK);
  pPager->state = PAGER_UNLOCK;
  return rc;
}

/*
** Acquire a write-lock on the database.  The lock is removed when
** the any of the following happen:
................................................................................
  assert( pPager->state!=PAGER_UNLOCK );
  if( pPager->state==PAGER_SHARED ){
    assert( pPager->aInJournal==0 );
    if( MEMDB ){
      pPager->state = PAGER_EXCLUSIVE;
      pPager->origDbSize = pPager->dbSize;
    }else{
      rc = sqlite3Io.xLock(&pPager->fd, RESERVED_LOCK);
      if( rc==SQLITE_OK ){
        pPager->state = PAGER_RESERVED;
        if( exFlag ){
          rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
        }
      }
      if( rc!=SQLITE_OK ){
................................................................................
          assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
          CODEC(pPager, pData, pPg->pgno, 7);
          cksum = pager_cksum(pPager, pPg->pgno, pData);
          saved = *(u32*)PGHDR_TO_EXTRA(pPg, pPager);
          store32bits(cksum, pPg, pPager->pageSize);
          szPg = pPager->pageSize+8;
          store32bits(pPg->pgno, pPg, -4);
          rc = sqlite3Io.xWrite(&pPager->jfd, &((char*)pData)[-4], szPg);
          pPager->journalOff += szPg;
          TRACE4("JOURNAL %d page %d needSync=%d\n",
                  PAGERID(pPager), pPg->pgno, pPg->needSync);
          CODEC(pPager, pData, pPg->pgno, 0);
          *(u32*)PGHDR_TO_EXTRA(pPg, pPager) = saved;
          if( rc!=SQLITE_OK ){
            sqlite3pager_rollback(pPager);
................................................................................
        if( pHist->pStmt ){
          memcpy(pHist->pStmt, PGHDR_TO_DATA(pPg), pPager->pageSize);
        }
        TRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
      }else{
        store32bits(pPg->pgno, pPg, -4);
        CODEC(pPager, pData, pPg->pgno, 7);
        rc = sqlite3Io.xWrite(&pPager->stfd,((char*)pData)-4,
                               pPager->pageSize+4);
        TRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
        CODEC(pPager, pData, pPg->pgno, 0);
        if( rc!=SQLITE_OK ){
          sqlite3pager_rollback(pPager);
          pPager->errMask |= PAGER_ERR_FULL;
          return rc;
        }
................................................................................
    }
#endif
    pPager->pStmt = 0;
    pPager->state = PAGER_SHARED;
    return SQLITE_OK;
  }
  if( pPager->dirtyCache==0 ){
    /* Exit early (without doing the time-consuming sqlite3Io.xSync() calls)
    ** if there have been no changes to the database file. */
    assert( pPager->needSync==0 );
    rc = pager_unwritelock(pPager);
    pPager->dbSize = -1;
    return rc;
  }
  assert( pPager->journalOpen );
................................................................................
  if( !pPager->journalOpen ){
    pPager->stmtAutoopen = 1;
    return SQLITE_OK;
  }
  assert( pPager->journalOpen );
  pPager->aInStmt = sqliteMalloc( pPager->dbSize/8 + 1 );
  if( pPager->aInStmt==0 ){
    sqlite3Io.xLock(&pPager->fd, SHARED_LOCK);
    return SQLITE_NOMEM;
  }
#ifndef NDEBUG
  rc = sqlite3Io.xFileSize(&pPager->jfd, &pPager->stmtJSize);
  if( rc ) goto stmt_begin_failed;
  assert( pPager->stmtJSize == pPager->journalOff );
#endif
  pPager->stmtJSize = pPager->journalOff;
  pPager->stmtSize = pPager->dbSize;
  pPager->stmtHdrOff = 0;
  pPager->stmtCksum = pPager->cksumInit;
................................................................................
** Commit a statement.
*/
int sqlite3pager_stmt_commit(Pager *pPager){
  if( pPager->stmtInUse ){
    PgHdr *pPg, *pNext;
    TRACE2("STMT-COMMIT %d\n", PAGERID(pPager));
    if( !MEMDB ){
      sqlite3Io.xSeek(&pPager->stfd, 0);
      /* sqlite3Io.xTruncate(&pPager->stfd, 0); */
      sqliteFree( pPager->aInStmt );
      pPager->aInStmt = 0;
    }
    for(pPg=pPager->pStmt; pPg; pPg=pNext){
      pNext = pPg->pNextStmt;
      assert( pPg->inStmt );
      pPg->inStmt = 0;
................................................................................
    /* Write all dirty pages to the database file */
    pPg = pager_get_all_dirty_pages(pPager);
    rc = pager_write_pagelist(pPg);
    if( rc!=SQLITE_OK ) goto sync_exit;

    /* Sync the database file. */
    if( !pPager->noSync ){
      rc = sqlite3Io.xSync(&pPager->fd, 0);
    }

    pPager->state = PAGER_SYNCED;
  }

sync_exit:
  return rc;

Changes to src/pragma.c.

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
**    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 file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.103 2005/11/03 02:15:03 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
................................................................................
      if( sqlite3_temp_directory ){
        sqlite3VdbeSetNumCols(v, 1);
        sqlite3VdbeSetColName(v, 0, "temp_store_directory", P3_STATIC);
        sqlite3VdbeOp3(v, OP_String8, 0, 0, sqlite3_temp_directory, 0);
        sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
      }
    }else{
      if( zRight[0] && !sqlite3OsIsDirWritable(zRight) ){
        sqlite3ErrorMsg(pParse, "not a writable directory");
        goto pragma_out;
      }
      if( TEMP_STORE==0
       || (TEMP_STORE==1 && db->temp_store<=1)
       || (TEMP_STORE==2 && db->temp_store==1)
      ){







|







 







|







7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
**    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 file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.104 2005/11/26 00:25:03 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
................................................................................
      if( sqlite3_temp_directory ){
        sqlite3VdbeSetNumCols(v, 1);
        sqlite3VdbeSetColName(v, 0, "temp_store_directory", P3_STATIC);
        sqlite3VdbeOp3(v, OP_String8, 0, 0, sqlite3_temp_directory, 0);
        sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
      }
    }else{
      if( zRight[0] && !sqlite3Io.xIsDirWritable(zRight) ){
        sqlite3ErrorMsg(pParse, "not a writable directory");
        goto pragma_out;
      }
      if( TEMP_STORE==0
       || (TEMP_STORE==1 && db->temp_store<=1)
       || (TEMP_STORE==2 && db->temp_store==1)
      ){

Changes to src/tclsqlite.c.

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
....
2055
2056
2057
2058
2059
2060
2061

2062
2063
2064
2065
2066
2067
2068
2069

2070
2071
2072
2073
2074
2075
2076
**    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.
**
*************************************************************************
** A TCL Interface to SQLite
**
** $Id: tclsqlite.c,v 1.133 2005/10/05 10:40:15 drh Exp $
*/
#ifndef NO_TCL     /* Omit this whole file if TCL is unavailable */

#include "sqliteInt.h"
#include "hash.h"
#include "tcl.h"
#include <stdlib.h>
................................................................................
#ifdef SQLITE_TEST
  {
    extern int Sqlitetest1_Init(Tcl_Interp*);
    extern int Sqlitetest2_Init(Tcl_Interp*);
    extern int Sqlitetest3_Init(Tcl_Interp*);
    extern int Sqlitetest4_Init(Tcl_Interp*);
    extern int Sqlitetest5_Init(Tcl_Interp*);

    extern int Md5_Init(Tcl_Interp*);
    extern int Sqlitetestsse_Init(Tcl_Interp*);

    Sqlitetest1_Init(interp);
    Sqlitetest2_Init(interp);
    Sqlitetest3_Init(interp);
    Sqlitetest4_Init(interp);
    Sqlitetest5_Init(interp);

    Md5_Init(interp);
#ifdef SQLITE_SSE
    Sqlitetestsse_Init(interp);
#endif
  }
#endif
  if( argc>=2 || TCLSH==2 ){







|







 







>








>







7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
....
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
**    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.
**
*************************************************************************
** A TCL Interface to SQLite
**
** $Id: tclsqlite.c,v 1.134 2005/11/26 00:25:03 drh Exp $
*/
#ifndef NO_TCL     /* Omit this whole file if TCL is unavailable */

#include "sqliteInt.h"
#include "hash.h"
#include "tcl.h"
#include <stdlib.h>
................................................................................
#ifdef SQLITE_TEST
  {
    extern int Sqlitetest1_Init(Tcl_Interp*);
    extern int Sqlitetest2_Init(Tcl_Interp*);
    extern int Sqlitetest3_Init(Tcl_Interp*);
    extern int Sqlitetest4_Init(Tcl_Interp*);
    extern int Sqlitetest5_Init(Tcl_Interp*);
    extern int Sqlitetest6_Init(Tcl_Interp*);
    extern int Md5_Init(Tcl_Interp*);
    extern int Sqlitetestsse_Init(Tcl_Interp*);

    Sqlitetest1_Init(interp);
    Sqlitetest2_Init(interp);
    Sqlitetest3_Init(interp);
    Sqlitetest4_Init(interp);
    Sqlitetest5_Init(interp);
    Sqlitetest6_Init(interp);
    Md5_Init(interp);
#ifdef SQLITE_SSE
    Sqlitetestsse_Init(interp);
#endif
  }
#endif
  if( argc>=2 || TCLSH==2 ){

Changes to src/test1.c.

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
....
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
....
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
....
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
....
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
....
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
....
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
....
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the printf() interface to SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.165 2005/11/25 10:38:22 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  zCode = Tcl_GetString(objv[1]);
  for(i=0; i<200; i++){
    if( 0==strcmp(errorName(i), zCode) ) break;
  }
  Tcl_SetResult(interp, (char *)sqlite3ErrStr(i), 0);
  return TCL_OK;
}

static int sqlite3_crashparams(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
#ifdef OS_TEST
  int delay;
  if( objc!=3 ) goto bad_args;
  if( Tcl_GetIntFromObj(interp, objv[1], &delay) ) return TCL_ERROR;
  sqlite3SetCrashParams(delay, Tcl_GetString(objv[2]));
#endif
  return TCL_OK;

#ifdef OS_TEST
bad_args:
  Tcl_AppendResult(interp, "wrong # args: should be \"",
      Tcl_GetStringFromObj(objv[0], 0), "<delay> <filename>", 0);
  return TCL_ERROR;
#endif
}


/*
** Usage:    breakpoint
**
** This routine exists for one purpose - to provide a place to put a
** breakpoint with GDB that can be triggered using TCL code.  The use
** for this is when a particular test fails on (say) the 1485th iteration.
................................................................................
  if( objc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", 
       Tcl_GetString(objv[0]), " filename", 0);
    return TCL_ERROR;
  }

  pFile = sqliteMalloc(sizeof(OsFile));
  rc = sqlite3OsOpenReadWrite(Tcl_GetString(objv[1]), pFile, &dummy);
  if( rc!=SQLITE_OK ){
    sqliteFree(pFile);
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  makePointerStr(interp, zBuf, pFile);
  Tcl_SetResult(interp, zBuf, 0);
................................................................................
       Tcl_GetString(objv[0]), " filehandle", 0);
    return TCL_ERROR;
  }

  if( getFilePointer(interp, Tcl_GetString(objv[1]), &pFile) ){
    return TCL_ERROR;
  }
  rc = sqlite3OsClose(pFile);
  if( rc!=SQLITE_OK ){
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  sqliteFree(pFile);
  return TCL_OK;
}
................................................................................
  }

  if( getFilePointer(interp, Tcl_GetString(objv[1]), &pFile) ){
    return TCL_ERROR;
  }

  if( 0==strcmp("SHARED", Tcl_GetString(objv[2])) ){
    rc = sqlite3OsLock(pFile, SHARED_LOCK);
  }
  else if( 0==strcmp("RESERVED", Tcl_GetString(objv[2])) ){
    rc = sqlite3OsLock(pFile, RESERVED_LOCK);
  }
  else if( 0==strcmp("PENDING", Tcl_GetString(objv[2])) ){
    rc = sqlite3OsLock(pFile, PENDING_LOCK);
  }
  else if( 0==strcmp("EXCLUSIVE", Tcl_GetString(objv[2])) ){
    rc = sqlite3OsLock(pFile, EXCLUSIVE_LOCK);
  }else{
    Tcl_AppendResult(interp, "wrong # args: should be \"", 
        Tcl_GetString(objv[0]), 
        " filehandle (SHARED|RESERVED|PENDING|EXCLUSIVE)", 0);
    return TCL_ERROR;
  }

................................................................................
       Tcl_GetString(objv[0]), " filehandle", 0);
    return TCL_ERROR;
  }

  if( getFilePointer(interp, Tcl_GetString(objv[1]), &pFile) ){
    return TCL_ERROR;
  }
  rc = sqlite3OsUnlock(pFile, NO_LOCK);
  if( rc!=SQLITE_OK ){
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  return TCL_OK;
}

................................................................................
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  char zFile[SQLITE_TEMPNAME_SIZE];
  int rc;

  rc = sqlite3OsTempFileName(zFile);
  if( rc!=SQLITE_OK ){
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  Tcl_AppendResult(interp, zFile, 0);
  return TCL_OK;
}
................................................................................
     { "sqlite3OsUnlock",         test_sqlite3OsUnlock, 0    },
#endif
#ifndef SQLITE_OMIT_UTF16
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },
     { "add_test_function",       test_function, 0           },
#endif
     { "sqlite3_crashparams",     sqlite3_crashparams, 0     },
     { "sqlite3_test_errstr",     test_errstr, 0             },
     { "tcl_variable_type",       tcl_variable_type, 0       },
  };
  static int bitmask_size = sizeof(Bitmask)*8;
  int i;
  extern int sqlite3_os_trace;
  extern int sqlite3_where_trace;







|







 







<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<







 







|







 







|







 







|


|


|


|







 







|







 







|







 







<







9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
....
1407
1408
1409
1410
1411
1412
1413























1414
1415
1416
1417
1418
1419
1420
....
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
....
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
....
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
....
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
....
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
....
3159
3160
3161
3162
3163
3164
3165

3166
3167
3168
3169
3170
3171
3172
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the printf() interface to SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.166 2005/11/26 00:25:03 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  zCode = Tcl_GetString(objv[1]);
  for(i=0; i<200; i++){
    if( 0==strcmp(errorName(i), zCode) ) break;
  }
  Tcl_SetResult(interp, (char *)sqlite3ErrStr(i), 0);
  return TCL_OK;
}
























/*
** Usage:    breakpoint
**
** This routine exists for one purpose - to provide a place to put a
** breakpoint with GDB that can be triggered using TCL code.  The use
** for this is when a particular test fails on (say) the 1485th iteration.
................................................................................
  if( objc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", 
       Tcl_GetString(objv[0]), " filename", 0);
    return TCL_ERROR;
  }

  pFile = sqliteMalloc(sizeof(OsFile));
  rc = sqlite3Io.xOpenReadWrite(Tcl_GetString(objv[1]), pFile, &dummy);
  if( rc!=SQLITE_OK ){
    sqliteFree(pFile);
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  makePointerStr(interp, zBuf, pFile);
  Tcl_SetResult(interp, zBuf, 0);
................................................................................
       Tcl_GetString(objv[0]), " filehandle", 0);
    return TCL_ERROR;
  }

  if( getFilePointer(interp, Tcl_GetString(objv[1]), &pFile) ){
    return TCL_ERROR;
  }
  rc = sqlite3Io.xClose(pFile);
  if( rc!=SQLITE_OK ){
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  sqliteFree(pFile);
  return TCL_OK;
}
................................................................................
  }

  if( getFilePointer(interp, Tcl_GetString(objv[1]), &pFile) ){
    return TCL_ERROR;
  }

  if( 0==strcmp("SHARED", Tcl_GetString(objv[2])) ){
    rc = sqlite3Io.xLock(pFile, SHARED_LOCK);
  }
  else if( 0==strcmp("RESERVED", Tcl_GetString(objv[2])) ){
    rc = sqlite3Io.xLock(pFile, RESERVED_LOCK);
  }
  else if( 0==strcmp("PENDING", Tcl_GetString(objv[2])) ){
    rc = sqlite3Io.xLock(pFile, PENDING_LOCK);
  }
  else if( 0==strcmp("EXCLUSIVE", Tcl_GetString(objv[2])) ){
    rc = sqlite3Io.xLock(pFile, EXCLUSIVE_LOCK);
  }else{
    Tcl_AppendResult(interp, "wrong # args: should be \"", 
        Tcl_GetString(objv[0]), 
        " filehandle (SHARED|RESERVED|PENDING|EXCLUSIVE)", 0);
    return TCL_ERROR;
  }

................................................................................
       Tcl_GetString(objv[0]), " filehandle", 0);
    return TCL_ERROR;
  }

  if( getFilePointer(interp, Tcl_GetString(objv[1]), &pFile) ){
    return TCL_ERROR;
  }
  rc = sqlite3Io.xUnlock(pFile, NO_LOCK);
  if( rc!=SQLITE_OK ){
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  return TCL_OK;
}

................................................................................
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  char zFile[SQLITE_TEMPNAME_SIZE];
  int rc;

  rc = sqlite3Io.xTempFileName(zFile);
  if( rc!=SQLITE_OK ){
    Tcl_SetResult(interp, (char *)errorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  Tcl_AppendResult(interp, zFile, 0);
  return TCL_OK;
}
................................................................................
     { "sqlite3OsUnlock",         test_sqlite3OsUnlock, 0    },
#endif
#ifndef SQLITE_OMIT_UTF16
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },
     { "add_test_function",       test_function, 0           },
#endif

     { "sqlite3_test_errstr",     test_errstr, 0             },
     { "tcl_variable_type",       tcl_variable_type, 0       },
  };
  static int bitmask_size = sizeof(Bitmask)*8;
  int i;
  extern int sqlite3_os_trace;
  extern int sqlite3_where_trace;

Changes to src/test2.c.

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
...
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the pager.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test2.c,v 1.35 2005/11/04 22:03:30 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................
  if( argc!=3 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " N-MEGABYTES FILE\"", 0);
    return TCL_ERROR;
  }
  if( Tcl_GetInt(interp, argv[1], &n) ) return TCL_ERROR;
  memset(&fd, 0, sizeof(fd));
  rc = sqlite3OsOpenReadWrite(argv[2], &fd, &readOnly);
  if( rc ){
    Tcl_AppendResult(interp, "open failed: ", errorName(rc), 0);
    return TCL_ERROR;
  }
  offset = n;
  offset *= 1024*1024;
  rc = sqlite3OsSeek(&fd, offset);
  if( rc ){
    Tcl_AppendResult(interp, "seek failed: ", errorName(rc), 0);
    return TCL_ERROR;
  }
  rc = sqlite3OsWrite(&fd, "Hello, World!", 14);
  sqlite3OsClose(&fd);
  if( rc ){
    Tcl_AppendResult(interp, "write failed: ", errorName(rc), 0);
    return TCL_ERROR;
  }
  return TCL_OK;
}
#endif







|







 







|






|




|
|







9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
...
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the pager.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test2.c,v 1.36 2005/11/26 00:25:04 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................
  if( argc!=3 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " N-MEGABYTES FILE\"", 0);
    return TCL_ERROR;
  }
  if( Tcl_GetInt(interp, argv[1], &n) ) return TCL_ERROR;
  memset(&fd, 0, sizeof(fd));
  rc = sqlite3Io.xOpenReadWrite(argv[2], &fd, &readOnly);
  if( rc ){
    Tcl_AppendResult(interp, "open failed: ", errorName(rc), 0);
    return TCL_ERROR;
  }
  offset = n;
  offset *= 1024*1024;
  rc = sqlite3Io.xSeek(&fd, offset);
  if( rc ){
    Tcl_AppendResult(interp, "seek failed: ", errorName(rc), 0);
    return TCL_ERROR;
  }
  rc = sqlite3Io.xWrite(&fd, "Hello, World!", 14);
  sqlite3Io.xClose(&fd);
  if( rc ){
    Tcl_AppendResult(interp, "write failed: ", errorName(rc), 0);
    return TCL_ERROR;
  }
  return TCL_OK;
}
#endif

Added src/test6.c.





























































































































































































































































































































































































































































































































































































































































































































































































































































































































































































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/*
** 2004 May 22
**
** 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 file contains code that modified the OS layer in order to simulate
** the effect on the database file of an OS crash or power failure.  This
** is used to test the ability of SQLite to recover from those situations.
*/
#if SQLITE_TEST          /* This file is used for the testing only */
#include "sqliteInt.h"
#include "os.h"
#include "tcl.h"

/*
** A copy of the original sqlite3Io structure
*/
static struct sqlite3IoVtbl origIo;

/*
** The pAux part of OsFile points to this structure.
*/
typedef struct OsTestFile OsTestFile;
struct OsTestFile {
  u8 **apBlk;         /* Array of blocks that have been written to. */
  int nBlk;           /* Size of apBlock. */
  int nMaxWrite;      /* Largest offset written to. */
  char *zName;        /* File name */
  OsFile *pBase;      /* Base class */
  OsTestFile *pNext;  /* Next in a list of them all */
};

/*
** Size of a simulated disk block
*/
#define BLOCKSIZE 512
#define BLOCK_OFFSET(x) ((x) * BLOCKSIZE)


/*
** The following variables control when a simulated crash occurs.
**
** If iCrashDelay is non-zero, then zCrashFile contains (full path) name of
** a file that SQLite will call sqlite3OsSync() on. Each time this happens
** iCrashDelay is decremented. If iCrashDelay is zero after being
** decremented, a "crash" occurs during the sync() operation.
**
** In other words, a crash occurs the iCrashDelay'th time zCrashFile is
** synced.
*/
static int iCrashDelay = 0;
static char zCrashFile[500];

/*
** Set the value of the two crash parameters.
*/
static void setCrashParams(int iDelay, char const *zFile){
  sqlite3OsEnterMutex();
  assert( strlen(zFile)<sizeof(zCrashFile) );
  strcpy(zCrashFile, zFile);
  iCrashDelay = iDelay;
  sqlite3OsLeaveMutex();
}

/*
** File zPath is being sync()ed. Return non-zero if this should
** cause a crash.
*/
static int crashRequired(char const *zPath){
  int r;
  int n;
  sqlite3OsEnterMutex();
  n = strlen(zCrashFile);
  if( zCrashFile[n-1]=='*' ){
    n--;
  }else if( strlen(zPath)>n ){
    n = strlen(zPath);
  }
  r = 0;
  if( iCrashDelay>0 && strncmp(zPath, zCrashFile, n)==0 ){
    iCrashDelay--;
    if( iCrashDelay<=0 ){
      r = 1;
    }
  }
  sqlite3OsLeaveMutex();
  return r;
}

/*
** A list of all open files.
*/
static OsTestFile *pAllFiles = 0;

/*
** Initialise the os_test.c specific fields of pFile.
*/
static void initFile(OsFile *id, char const *zName){
  OsTestFile *pFile = sqliteMalloc(sizeof(OsTestFile) + strlen(zName)+1);
  id->pAux = pFile;
  pFile->nMaxWrite = 0; 
  pFile->nBlk = 0; 
  pFile->apBlk = 0; 
  pFile->zName = (char *)(&pFile[1]);
  strcpy(pFile->zName, zName);
  pFile->pBase = id;
  pFile->pNext = pAllFiles;
  pAllFiles = pFile;
}

/*
** Undo the work done by initFile. Delete the OsTestFile structure
** and unlink the structure from the pAllFiles list.
*/
static void closeFile(OsFile *id){
  OsTestFile *pFile = (OsTestFile*)id->pAux;
  if( pFile==pAllFiles ){
    pAllFiles = pFile->pNext;
  }else{
    OsTestFile *p;
    for(p=pAllFiles; p->pNext!=pFile; p=p->pNext ){
      assert( p );
    }
    p->pNext = pFile->pNext;
  }
  sqliteFree(pFile);
}

/*
** Return the current seek offset from the start of the file. This
** is unix-only code.
*/
static i64 osTell(OsTestFile *pFile){
  return lseek(pFile->pBase->h, 0, SEEK_CUR);
}

/*
** Load block 'blk' into the cache of pFile.
*/
static int cacheBlock(OsTestFile *pFile, int blk){
  if( blk>=pFile->nBlk ){
    int n = ((pFile->nBlk * 2) + 100 + blk);
    /* if( pFile->nBlk==0 ){ printf("DIRTY %s\n", pFile->zName); } */
    pFile->apBlk = (u8 **)sqliteRealloc(pFile->apBlk, n * sizeof(u8*));
    if( !pFile->apBlk ) return SQLITE_NOMEM;
    memset(&pFile->apBlk[pFile->nBlk], 0, (n - pFile->nBlk)*sizeof(u8*));
    pFile->nBlk = n;
  }

  if( !pFile->apBlk[blk] ){
    i64 filesize;
    int rc;

    u8 *p = sqliteMalloc(BLOCKSIZE);
    if( !p ) return SQLITE_NOMEM;
    pFile->apBlk[blk] = p;

    rc = origIo.xFileSize(pFile->pBase, &filesize);
    if( rc!=SQLITE_OK ) return rc;

    if( BLOCK_OFFSET(blk)<filesize ){
      int len = BLOCKSIZE;
      rc = origIo.xSeek(pFile->pBase, blk*BLOCKSIZE);
      if( BLOCK_OFFSET(blk+1)>filesize ){
        len = filesize - BLOCK_OFFSET(blk);
      }
      if( rc!=SQLITE_OK ) return rc;
      rc = origIo.xRead(pFile->pBase, p, len);
      if( rc!=SQLITE_OK ) return rc;
    }
  }

  return SQLITE_OK;
}

/*
** Write the cache of pFile to disk. If crash is non-zero, randomly
** skip blocks when writing. The cache is deleted before returning.
*/
static int writeCache2(OsTestFile *pFile, int crash){
  int i;
  int nMax = pFile->nMaxWrite;
  i64 offset;
  int rc = SQLITE_OK;

  offset = osTell(pFile);
  for(i=0; i<pFile->nBlk; i++){
    u8 *p = pFile->apBlk[i];
    if( p ){
      int skip = 0;
      int trash = 0;
      if( crash ){
        char random;
        sqlite3Randomness(1, &random);
        if( random & 0x01 ){
          if( random & 0x02 ){
            trash = 1;
#ifdef TRACE_WRITECACHE
printf("Trashing block %d of %s\n", i, pFile->zName); 
#endif
          }else{
            skip = 1;
#ifdef TRACE_WRITECACHE
printf("Skiping block %d of %s\n", i, pFile->zName); 
#endif
          }
        }else{
#ifdef TRACE_WRITECACHE
printf("Writing block %d of %s\n", i, pFile->zName); 
#endif
        }
      }
      if( rc==SQLITE_OK ){
        rc = origIo.xSeek(pFile->pBase, BLOCK_OFFSET(i));
      }
      if( rc==SQLITE_OK && !skip ){
        int len = BLOCKSIZE;
        if( BLOCK_OFFSET(i+1)>nMax ){
          len = nMax-BLOCK_OFFSET(i);
        }
        if( len>0 ){
          if( trash ){
            sqlite3Randomness(len, p);
          }
          rc = origIo.xWrite(pFile->pBase, p, len);
        }
      }
      sqliteFree(p);
    }
  }
  sqliteFree(pFile->apBlk);
  pFile->nBlk = 0;
  pFile->apBlk = 0;
  pFile->nMaxWrite = 0;

  if( rc==SQLITE_OK ){
    rc = origIo.xSeek(pFile->pBase, offset);
  }
  return rc;
}

/*
** Write the cache to disk.
*/
static int writeCache(OsTestFile *pFile){
  if( pFile->apBlk ){
    int c = crashRequired(pFile->zName);
    if( c ){
      OsTestFile *p;
#ifdef TRACE_WRITECACHE
      printf("\nCrash during sync of %s\n", pFile->zName);
#endif
      for(p=pAllFiles; p; p=p->pNext){
        writeCache2(p, 1);
      }
      exit(-1);
    }else{
      return writeCache2(pFile, 0);
    }
  }
  return SQLITE_OK;
}

/*
** Close the file.
*/
static int crashClose(OsFile *id){
  if( id->pAux ) return SQLITE_OK;
  if( id->isOpen ){
    /* printf("CLOSE %s (%d blocks)\n", (*id)->zName, (*id)->nBlk); */
    writeCache((OsTestFile*)id->pAux);
    origIo.xClose(id);
  }
  closeFile(id);
  return SQLITE_OK;
}

static int crashRead(OsFile *id, void *pBuf, int amt){
  i64 offset;       /* The current offset from the start of the file */
  i64 end;          /* The byte just past the last byte read */
  int blk;            /* Block number the read starts on */
  int i;
  u8 *zCsr;
  int rc = SQLITE_OK;
  OsTestFile *pFile = (OsTestFile*)id->pAux;

  offset = osTell(pFile);
  end = offset+amt;
  blk = (offset/BLOCKSIZE);

  zCsr = (u8 *)pBuf;
  for(i=blk; i*BLOCKSIZE<end; i++){
    int off = 0;
    int len = 0;


    if( BLOCK_OFFSET(i) < offset ){
      off = offset-BLOCK_OFFSET(i);
    }
    len = BLOCKSIZE - off;
    if( BLOCK_OFFSET(i+1) > end ){
      len = len - (BLOCK_OFFSET(i+1)-end);
    }

    if( i<pFile->nBlk && pFile->apBlk[i]){
      u8 *pBlk = pFile->apBlk[i];
      memcpy(zCsr, &pBlk[off], len);
    }else{
      rc = origIo.xSeek(id, BLOCK_OFFSET(i) + off);
      if( rc!=SQLITE_OK ) return rc;
      rc = origIo.xRead(id, zCsr, len);
      if( rc!=SQLITE_OK ) return rc;
    }

    zCsr += len;
  }
  assert( zCsr==&((u8 *)pBuf)[amt] );

  rc = origIo.xSeek(id, end);
  return rc;
}

static int crashWrite(OsFile *id, const void *pBuf, int amt){
  i64 offset;       /* The current offset from the start of the file */
  i64 end;          /* The byte just past the last byte written */
  int blk;            /* Block number the write starts on */
  int i;
  const u8 *zCsr;
  int rc = SQLITE_OK;
  OsTestFile *pFile =  (OsTestFile*)id->pAux;

  offset = osTell(pFile);
  end = offset+amt;
  blk = (offset/BLOCKSIZE);

  zCsr = (u8 *)pBuf;
  for(i=blk; i*BLOCKSIZE<end; i++){
    u8 *pBlk;
    int off = 0;
    int len = 0;

    /* Make sure the block is in the cache */
    rc = cacheBlock(pFile, i);
    if( rc!=SQLITE_OK ) return rc;

    /* Write into the cache */
    pBlk = pFile->apBlk[i];
    assert( pBlk );

    if( BLOCK_OFFSET(i) < offset ){
      off = offset-BLOCK_OFFSET(i);
    }
    len = BLOCKSIZE - off;
    if( BLOCK_OFFSET(i+1) > end ){
      len = len - (BLOCK_OFFSET(i+1)-end);
    }
    memcpy(&pBlk[off], zCsr, len);
    zCsr += len;
  }
  if( pFile->nMaxWrite<end ){
    pFile->nMaxWrite = end;
  }
  assert( zCsr==&((u8 *)pBuf)[amt] );

  rc = origIo.xSeek(id, end);
  return rc;
}

/*
** Sync the file. First flush the write-cache to disk, then call the
** real sync() function.
*/
static int crashSync(OsFile *id, int dataOnly){
  int rc;
  /* printf("SYNC %s (%d blocks)\n", (*id)->zName, (*id)->nBlk); */
  rc = writeCache((OsTestFile*)id->pAux);
  if( rc!=SQLITE_OK ) return rc;
  rc = origIo.xSync(id, dataOnly);
  return rc;
}

/*
** Truncate the file. Set the internal OsFile.nMaxWrite variable to the new
** file size to ensure that nothing in the write-cache past this point
** is written to disk.
*/
static int crashTruncate(OsFile *id, i64 nByte){
  OsTestFile *pFile = (OsTestFile*)id->pAux;
  pFile->nMaxWrite = nByte;
  return origIo.xTruncate(id, nByte);
}

/*
** Return the size of the file. If the cache contains a write that extended
** the file, then return this size instead of the on-disk size.
*/
static int crashFileSize(OsFile *id, i64 *pSize){
  int rc = origIo.xFileSize(id, pSize);
  OsTestFile *pFile = (OsTestFile*)id->pAux;
  if( rc==SQLITE_OK && pSize && *pSize<pFile->nMaxWrite ){
    *pSize = pFile->nMaxWrite;
  }
  return rc;
}

/*
** The three functions used to open files. All that is required is to
** initialise the os_test.c specific fields and then call the corresponding
** os_unix.c function to really open the file.
*/
static int crashOpenReadWrite(const char *zFilename, OsFile *id, int *pRdonly){
  initFile(id, zFilename);
  return origIo.xOpenReadWrite(zFilename, id, pRdonly);
}
static int crashOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  initFile(id, zFilename);
  return origIo.xOpenExclusive(zFilename, id, delFlag);
}
static int crashOpenReadOnly(const char *zFilename, OsFile *id){
  initFile(id, zFilename);
  return origIo.xOpenReadOnly(zFilename, id);
}

/*
** tclcmd:   sqlite_crashparams DELAY CRASHFILE
**
** This procedure implements a TCL command that enables crash testing
** in testfixture.  Once enabled, crash testing cannot be disabled.
*/
static int crashParamsObjCmd(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int delay;
  const char *zFile;
  int nFile;
  if( objc!=3 ){
    Tcl_WrongNumArgs(interp, 1, objv, "DELAY CRASHFILE");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[1], &delay) ) return TCL_ERROR;
  zFile = Tcl_GetStringFromObj(objv[2], &nFile);
  if( nFile>=sizeof(zCrashFile)-1 ){
    Tcl_AppendResult(interp, "crash file name too big", 0);
    return TCL_ERROR;
  }
  setCrashParams(delay, zFile);
  origIo = sqlite3Io;
  sqlite3Io.xRead = crashRead;
  sqlite3Io.xWrite = crashWrite;
  sqlite3Io.xClose = crashClose;
  sqlite3Io.xSync = crashSync;
  sqlite3Io.xTruncate = crashTruncate;
  sqlite3Io.xFileSize = crashFileSize;
  sqlite3Io.xOpenReadWrite = crashOpenReadWrite;
  sqlite3Io.xOpenExclusive = crashOpenExclusive;
  sqlite3Io.xOpenReadOnly = crashOpenReadOnly;
  return TCL_OK;
}

/*
** This procedure registers the TCL procedures defined in this file.
*/
int Sqlitetest6_Init(Tcl_Interp *interp){
  Tcl_CreateObjCommand(interp, "sqlite3_crashparams", crashParamsObjCmd, 0, 0);
  return TCL_OK;
}

#endif /* SQLITE_TEST */

Changes to src/vacuum.c.

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**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.47 2005/11/04 22:03:30 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"

#ifndef SQLITE_OMIT_VACUUM
/*
** Generate a random name of 20 character in length.
................................................................................
  ** run more than once or twice is vanishingly small.  We are certain
  ** enough that this loop will always terminate (and terminate quickly)
  ** that we don't even bother to set a maximum loop count.
  */
  do {
    zTemp[nFilename] = '-';
    randomName((unsigned char*)&zTemp[nFilename+1]);
  } while( sqlite3OsFileExists(zTemp) );

  /* Attach the temporary database as 'vacuum_db'. The synchronous pragma
  ** can be set to 'off' for this file, as it is not recovered if a crash
  ** occurs anyway. The integrity of the database is maintained by a
  ** (possibly synchronous) transaction opened on the main database before
  ** sqlite3BtreeCopyFile() is called.
  **
................................................................................
  */
  db->autoCommit = 1;
  rc2 = execSql(db, "DETACH vacuum_db;");
  if( rc==SQLITE_OK ){
    rc = rc2;
  }
  if( zTemp ){
    sqlite3OsDelete(zTemp);
    sqliteFree(zTemp);
  }
  sqliteFree( zSql );
  sqlite3ResetInternalSchema(db, 0);
#endif

  return rc;
}







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**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.48 2005/11/26 00:25:04 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"

#ifndef SQLITE_OMIT_VACUUM
/*
** Generate a random name of 20 character in length.
................................................................................
  ** run more than once or twice is vanishingly small.  We are certain
  ** enough that this loop will always terminate (and terminate quickly)
  ** that we don't even bother to set a maximum loop count.
  */
  do {
    zTemp[nFilename] = '-';
    randomName((unsigned char*)&zTemp[nFilename+1]);
  } while( sqlite3Io.xFileExists(zTemp) );

  /* Attach the temporary database as 'vacuum_db'. The synchronous pragma
  ** can be set to 'off' for this file, as it is not recovered if a crash
  ** occurs anyway. The integrity of the database is maintained by a
  ** (possibly synchronous) transaction opened on the main database before
  ** sqlite3BtreeCopyFile() is called.
  **
................................................................................
  */
  db->autoCommit = 1;
  rc2 = execSql(db, "DETACH vacuum_db;");
  if( rc==SQLITE_OK ){
    rc = rc2;
  }
  if( zTemp ){
    sqlite3Io.xDelete(zTemp);
    sqliteFree(zTemp);
  }
  sqliteFree( zSql );
  sqlite3ResetInternalSchema(db, 0);
#endif

  return rc;
}

Changes to src/vdbe.c.

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**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.499 2005/11/24 14:34:36 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................
    if( p->trace ){
      if( pc==0 ){
        printf("VDBE Execution Trace:\n");
        sqlite3VdbePrintSql(p);
      }
      sqlite3VdbePrintOp(p->trace, pc, pOp);
    }
    if( p->trace==0 && pc==0 && sqlite3OsFileExists("vdbe_sqltrace") ){
      sqlite3VdbePrintSql(p);
    }
#endif
      

    /* Check to see if we need to simulate an interrupt.  This only happens
    ** if we have a special test build.







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**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.500 2005/11/26 00:25:04 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................
    if( p->trace ){
      if( pc==0 ){
        printf("VDBE Execution Trace:\n");
        sqlite3VdbePrintSql(p);
      }
      sqlite3VdbePrintOp(p->trace, pc, pOp);
    }
    if( p->trace==0 && pc==0 && sqlite3Io.xFileExists("vdbe_sqltrace") ){
      sqlite3VdbePrintSql(p);
    }
#endif
      

    /* Check to see if we need to simulate an interrupt.  This only happens
    ** if we have a special test build.

Changes to src/vdbeaux.c.

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  p->aLabel = 0;

  *pMaxFuncArgs = nMaxArgs;
  *pMaxStack = nMaxStack;

  /* If we never rollback a statement transaction, then statement
  ** transactions are not needed.  So change every OP_Statement
  ** opcode into an OP_Noop.  This avoid a call to sqlite3OsOpenExclusive()
  ** which can be expensive on some platforms.
  */
  if( hasStatementBegin && !doesStatementRollback ){
    for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
      if( pOp->opcode==OP_Statement ){
        pOp->opcode = OP_Noop;
      }
................................................................................
  }
  for(n=0; n<p->nMem; n++){
    p->aMem[n].flags = MEM_Null;
  }

#ifdef SQLITE_DEBUG
  if( (p->db->flags & SQLITE_VdbeListing)!=0
    || sqlite3OsFileExists("vdbe_explain")
  ){
    int i;
    printf("VDBE Program Listing:\n");
    sqlite3VdbePrintSql(p);
    for(i=0; i<p->nOp; i++){
      sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
    }
  }
  if( sqlite3OsFileExists("vdbe_trace") ){
    p->trace = stdout;
  }
#endif
  p->pTos = &p->aStack[-1];
  p->pc = -1;
  p->rc = SQLITE_OK;
  p->uniqueCnt = 0;
................................................................................
      u32 random;
      sqliteFree(zMaster);
      sqlite3Randomness(sizeof(random), &random);
      zMaster = sqlite3MPrintf("%s-mj%08X", zMainFile, random&0x7fffffff);
      if( !zMaster ){
        return SQLITE_NOMEM;
      }
    }while( sqlite3OsFileExists(zMaster) );

    /* Open the master journal. */
    memset(&master, 0, sizeof(master));
    rc = sqlite3OsOpenExclusive(zMaster, &master, 0);
    if( rc!=SQLITE_OK ){
      sqliteFree(zMaster);
      return rc;
    }
 
    /* Write the name of each database file in the transaction into the new
    ** master journal file. If an error occurs at this point close
................................................................................
      if( i==1 ) continue;   /* Ignore the TEMP database */
      if( pBt && sqlite3BtreeIsInTrans(pBt) ){
        char const *zFile = sqlite3BtreeGetJournalname(pBt);
        if( zFile[0]==0 ) continue;  /* Ignore :memory: databases */
        if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
          needSync = 1;
        }
        rc = sqlite3OsWrite(&master, zFile, strlen(zFile)+1);
        if( rc!=SQLITE_OK ){
          sqlite3OsClose(&master);
          sqlite3OsDelete(zMaster);
          sqliteFree(zMaster);
          return rc;
        }
      }
    }


    /* Sync the master journal file. Before doing this, open the directory
    ** the master journal file is store in so that it gets synced too.
    */
    zMainFile = sqlite3BtreeGetDirname(db->aDb[0].pBt);
    rc = sqlite3OsOpenDirectory(zMainFile, &master);
    if( rc!=SQLITE_OK ||
          (needSync && (rc=sqlite3OsSync(&master,0))!=SQLITE_OK) ){
      sqlite3OsClose(&master);
      sqlite3OsDelete(zMaster);
      sqliteFree(zMaster);
      return rc;
    }

    /* Sync all the db files involved in the transaction. The same call
    ** sets the master journal pointer in each individual journal. If
    ** an error occurs here, do not delete the master journal file.
................................................................................
    ** occured.
    */
    for(i=0; i<db->nDb; i++){ 
      Btree *pBt = db->aDb[i].pBt;
      if( pBt && sqlite3BtreeIsInTrans(pBt) ){
        rc = sqlite3BtreeSync(pBt, zMaster);
        if( rc!=SQLITE_OK ){
          sqlite3OsClose(&master);
          sqliteFree(zMaster);
          return rc;
        }
      }
    }
    sqlite3OsClose(&master);

    /* Delete the master journal file. This commits the transaction. After
    ** doing this the directory is synced again before any individual
    ** transaction files are deleted.
    */
    rc = sqlite3OsDelete(zMaster);
    assert( rc==SQLITE_OK );
    sqliteFree(zMaster);
    zMaster = 0;
    rc = sqlite3OsSyncDirectory(zMainFile);
    if( rc!=SQLITE_OK ){
      /* This is not good. The master journal file has been deleted, but
      ** the directory sync failed. There is no completely safe course of
      ** action from here. The individual journals contain the name of the
      ** master journal file, but there is no way of knowing if that
      ** master journal exists now or if it will exist after the operating
      ** system crash that may follow the fsync() failure.







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  p->aLabel = 0;

  *pMaxFuncArgs = nMaxArgs;
  *pMaxStack = nMaxStack;

  /* If we never rollback a statement transaction, then statement
  ** transactions are not needed.  So change every OP_Statement
  ** opcode into an OP_Noop.  This avoid a call to sqlite3Io.xOpenExclusive()
  ** which can be expensive on some platforms.
  */
  if( hasStatementBegin && !doesStatementRollback ){
    for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
      if( pOp->opcode==OP_Statement ){
        pOp->opcode = OP_Noop;
      }
................................................................................
  }
  for(n=0; n<p->nMem; n++){
    p->aMem[n].flags = MEM_Null;
  }

#ifdef SQLITE_DEBUG
  if( (p->db->flags & SQLITE_VdbeListing)!=0
    || sqlite3Io.xFileExists("vdbe_explain")
  ){
    int i;
    printf("VDBE Program Listing:\n");
    sqlite3VdbePrintSql(p);
    for(i=0; i<p->nOp; i++){
      sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
    }
  }
  if( sqlite3Io.xFileExists("vdbe_trace") ){
    p->trace = stdout;
  }
#endif
  p->pTos = &p->aStack[-1];
  p->pc = -1;
  p->rc = SQLITE_OK;
  p->uniqueCnt = 0;
................................................................................
      u32 random;
      sqliteFree(zMaster);
      sqlite3Randomness(sizeof(random), &random);
      zMaster = sqlite3MPrintf("%s-mj%08X", zMainFile, random&0x7fffffff);
      if( !zMaster ){
        return SQLITE_NOMEM;
      }
    }while( sqlite3Io.xFileExists(zMaster) );

    /* Open the master journal. */
    memset(&master, 0, sizeof(master));
    rc = sqlite3Io.xOpenExclusive(zMaster, &master, 0);
    if( rc!=SQLITE_OK ){
      sqliteFree(zMaster);
      return rc;
    }
 
    /* Write the name of each database file in the transaction into the new
    ** master journal file. If an error occurs at this point close
................................................................................
      if( i==1 ) continue;   /* Ignore the TEMP database */
      if( pBt && sqlite3BtreeIsInTrans(pBt) ){
        char const *zFile = sqlite3BtreeGetJournalname(pBt);
        if( zFile[0]==0 ) continue;  /* Ignore :memory: databases */
        if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
          needSync = 1;
        }
        rc = sqlite3Io.xWrite(&master, zFile, strlen(zFile)+1);
        if( rc!=SQLITE_OK ){
          sqlite3Io.xClose(&master);
          sqlite3Io.xDelete(zMaster);
          sqliteFree(zMaster);
          return rc;
        }
      }
    }


    /* Sync the master journal file. Before doing this, open the directory
    ** the master journal file is store in so that it gets synced too.
    */
    zMainFile = sqlite3BtreeGetDirname(db->aDb[0].pBt);
    rc = sqlite3Io.xOpenDirectory(zMainFile, &master);
    if( rc!=SQLITE_OK ||
          (needSync && (rc=sqlite3Io.xSync(&master,0))!=SQLITE_OK) ){
      sqlite3Io.xClose(&master);
      sqlite3Io.xDelete(zMaster);
      sqliteFree(zMaster);
      return rc;
    }

    /* Sync all the db files involved in the transaction. The same call
    ** sets the master journal pointer in each individual journal. If
    ** an error occurs here, do not delete the master journal file.
................................................................................
    ** occured.
    */
    for(i=0; i<db->nDb; i++){ 
      Btree *pBt = db->aDb[i].pBt;
      if( pBt && sqlite3BtreeIsInTrans(pBt) ){
        rc = sqlite3BtreeSync(pBt, zMaster);
        if( rc!=SQLITE_OK ){
          sqlite3Io.xClose(&master);
          sqliteFree(zMaster);
          return rc;
        }
      }
    }
    sqlite3Io.xClose(&master);

    /* Delete the master journal file. This commits the transaction. After
    ** doing this the directory is synced again before any individual
    ** transaction files are deleted.
    */
    rc = sqlite3Io.xDelete(zMaster);
    assert( rc==SQLITE_OK );
    sqliteFree(zMaster);
    zMaster = 0;
    rc = sqlite3Io.xSyncDirectory(zMainFile);
    if( rc!=SQLITE_OK ){
      /* This is not good. The master journal file has been deleted, but
      ** the directory sync failed. There is no completely safe course of
      ** action from here. The individual journals contain the name of the
      ** master journal file, but there is no way of knowing if that
      ** master journal exists now or if it will exist after the operating
      ** system crash that may follow the fsync() failure.

Changes to test/crash.test.

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#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# The focus of this file is testing the ability of the database to
# uses its rollback journal to recover intact (no database corruption)
# from a power failure during the middle of a COMMIT.  The special test
# module "crashtest" compiled with the special "os_test.c" backend is used.
# The os_test.c simulates the kind of file corruption that can occur
# when writes are happening at the moment of power loss.
# 
# The special crash-test module with its os_test.c backend only works
# on Unix.
#
# $Id: crash.test,v 1.19 2005/09/17 17:05:19 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# set repeats 100
set repeats 10

................................................................................

  puts $f "db eval {"
  puts $f   "$sql"
  puts $f "}"
  close $f

  set r [catch {
    exec [file join . crashtest] crash.tcl >@stdout
  } msg]
  lappend r $msg
}

# The following procedure computes a "signature" for table "abc".  If
# abc changes in any way, the signature should change.  
proc signature {} {







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#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# The focus of this file is testing the ability of the database to
# uses its rollback journal to recover intact (no database corruption)
# from a power failure during the middle of a COMMIT.  The OS interface
# modules are overloaded in a separate instance of testfixture using
# the modified I/O routines found in test6.c.  These routines allow us
# to simulate the kind of file damage that occurs after a power failure.
#



# $Id: crash.test,v 1.20 2005/11/26 00:25:04 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# set repeats 100
set repeats 10

................................................................................

  puts $f "db eval {"
  puts $f   "$sql"
  puts $f "}"
  close $f

  set r [catch {
    exec [info nameofexec] crash.tcl >@stdout
  } msg]
  lappend r $msg
}

# The following procedure computes a "signature" for table "abc".  If
# abc changes in any way, the signature should change.  
proc signature {} {

Changes to test/tester.tcl.

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#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements some common TCL routines used for regression
# testing the SQLite library
#
# $Id: tester.tcl,v 1.51 2005/11/04 22:03:30 drh Exp $

# Make sure tclsqlite3 was compiled correctly.  Abort now with an
# error message if not.
#
if {[sqlite3 -tcl-uses-utf]} {
  if {"\u1234"=="u1234"} {
    puts stderr "***** BUILD PROBLEM *****"
................................................................................
  puts $f "db eval {pragma cache_size = 10}"
  puts $f "db eval {"
  puts $f   "$sql"
  puts $f "}"
  close $f

  set r [catch {
    exec [file join . crashtest] crash.tcl >@stdout
  } msg]
  lappend r $msg
}

# Usage: do_ioerr_test <test number> <options...>
#
# This proc is used to implement test cases that check that IO errors







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#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements some common TCL routines used for regression
# testing the SQLite library
#
# $Id: tester.tcl,v 1.52 2005/11/26 00:25:04 drh Exp $

# Make sure tclsqlite3 was compiled correctly.  Abort now with an
# error message if not.
#
if {[sqlite3 -tcl-uses-utf]} {
  if {"\u1234"=="u1234"} {
    puts stderr "***** BUILD PROBLEM *****"
................................................................................
  puts $f "db eval {pragma cache_size = 10}"
  puts $f "db eval {"
  puts $f   "$sql"
  puts $f "}"
  close $f

  set r [catch {
    exec [info nameofexec] crash.tcl >@stdout
  } msg]
  lappend r $msg
}

# Usage: do_ioerr_test <test number> <options...>
#
# This proc is used to implement test cases that check that IO errors