** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.50 2006/01/13 01:17:21 drh Exp $
**
** NOTES:
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system.
................................................................................
    min = va_arg(ap, int);
    max = va_arg(ap, int);
    nextC = va_arg(ap, int);
    pVal = va_arg(ap, int*);
    val = 0;
    while( N-- ){
      if( !isdigit(*(u8*)zDate) ){
        return cnt;
      }
      val = val*10 + *zDate - '0';
      zDate++;
    }
    if( val<min || val>max || (nextC!=0 && nextC!=*zDate) ){
      return cnt;
    }
    *pVal = val;
    zDate++;
    cnt++;
  }while( nextC );
  va_end(ap);

  return cnt;
}

/*
** Read text from z[] and convert into a floating point number.  Return
** the number of digits converted.
*/

** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.51 2006/01/15 00:13:16 drh Exp $
**
** NOTES:
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system.
................................................................................
    min = va_arg(ap, int);
    max = va_arg(ap, int);
    nextC = va_arg(ap, int);
    pVal = va_arg(ap, int*);
    val = 0;
    while( N-- ){
      if( !isdigit(*(u8*)zDate) ){
        goto end_getDigits;
      }
      val = val*10 + *zDate - '0';
      zDate++;
    }
    if( val<min || val>max || (nextC!=0 && nextC!=*zDate) ){
      goto end_getDigits;
    }
    *pVal = val;
    zDate++;
    cnt++;
  }while( nextC );
  va_end(ap);
end_getDigits:
  return cnt;
}

/*
** Read text from z[] and convert into a floating point number.  Return
** the number of digits converted.
*/

** is first opened.  All subsequent uses of the OsFile verify that the
** same thread is operating on the OsFile.  Some operating systems do
** not allow locks to be overridden by other threads and that restriction
** means that sqlite3* database handles cannot be moved from one thread
** to another.  This logic makes sure a user does not try to do that
** by mistake.
*/
#if defined(SQLITE_UNIX_THREADS) && !defined(SQLITE_ALLOW_XTHREAD_CONNECTIONS)
# define SET_THREADID(X)   (X)->tid = pthread_self()

# define CHECK_THREADID(X) (!pthread_equal((X)->tid, pthread_self()))
#else
# define SET_THREADID(X)
# define CHECK_THREADID(X) 0
#endif

/*
** Here is the dirt on POSIX advisory locks:  ANSI STD 1003.1 (1996)
................................................................................
** This variable records whether or not threads can override each others
** locks.
**
**    0:  No.  Threads cannot override each others locks.
**    1:  Yes.  Threads can override each others locks.
**   -1:  We don't know yet.
*/



static int threadsOverrideEachOthersLocks = -1;


/*
** This structure holds information passed into individual test
** threads by the testThreadLockingBehavior() routine.
*/
struct threadTestData {
  int fd;                /* File to be locked */
................................................................................
}
#endif /* SQLITE_UNIX_THREADS */

/*
** Release a lockInfo structure previously allocated by findLockInfo().
*/
static void releaseLockInfo(struct lockInfo *pLock){

  pLock->nRef--;
  if( pLock->nRef==0 ){
    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
    sqliteFree(pLock);
  }
}

/*
** Release a openCnt structure previously allocated by findLockInfo().
*/
static void releaseOpenCnt(struct openCnt *pOpen){

  pOpen->nRef--;
  if( pOpen->nRef==0 ){
    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
    sqliteFree(pOpen->aPending);
    sqliteFree(pOpen);
  }
}

/*
** Given a file descriptor, locate lockInfo and openCnt structures that
** describes that file descriptor.  Create a new ones if necessary.  The
** return values might be unset if an error occurs.
**
** Return the number of errors.
*/
static int findLockInfo(
  int fd,                      /* The file descriptor used in the key */
  struct lockInfo **ppLock,    /* Return the lockInfo structure here */
  struct openCnt **ppOpen      /* Return the openCnt structure here */
................................................................................
  struct openKey key2;
  struct stat statbuf;
  struct lockInfo *pLock;
  struct openCnt *pOpen;
  rc = fstat(fd, &statbuf);
  if( rc!=0 ) return 1;


  memset(&key1, 0, sizeof(key1));
  key1.dev = statbuf.st_dev;
  key1.ino = statbuf.st_ino;
#ifdef SQLITE_UNIX_THREADS
  if( threadsOverrideEachOthersLocks<0 ){
    testThreadLockingBehavior(fd);
  }
................................................................................
      rc = 1;
      goto exit_findlockinfo;
    }
  }else{
    pLock->nRef++;
  }
  *ppLock = pLock;

  pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2));
  if( pOpen==0 ){
    struct openCnt *pOld;
    pOpen = sqliteMallocRaw( sizeof(*pOpen) );
    if( pOpen==0 ){
      releaseLockInfo(pLock);
      rc = 1;
      goto exit_findlockinfo;
    }
    pOpen->key = key2;
    pOpen->nRef = 1;
    pOpen->nLock = 0;
    pOpen->nPending = 0;
    pOpen->aPending = 0;
    pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen);
    if( pOld!=0 ){
      assert( pOld==pOpen );
      sqliteFree(pOpen);
      releaseLockInfo(pLock);
      rc = 1;
      goto exit_findlockinfo;
    }
  }else{
    pOpen->nRef++;
  }
  *ppOpen = pOpen;


exit_findlockinfo:
  return rc;
}






































/*
** Delete the named file
*/
int sqlite3UnixDelete(const char *zFilename){
  unlink(zFilename);
  return SQLITE_OK;
}
................................................................................
** return zero.
*/
static int unixCheckReservedLock(OsFile *id){
  int r = 0;
  unixFile *pFile = (unixFile*)id;

  assert( pFile );
  if( CHECK_THREADID(pFile) ) return SQLITE_MISUSE;
  sqlite3OsEnterMutex(); /* Because pFile->pLock is shared across threads */

  /* Check if a thread in this process holds such a lock */
  if( pFile->pLock->locktype>SHARED_LOCK ){
    r = 1;
  }

................................................................................
  struct flock lock;
  int s;

  assert( pFile );
  TRACE7("LOCK    %d %s was %s(%s,%d) pid=%d\n", pFile->h,
      locktypeName(locktype), locktypeName(pFile->locktype),
      locktypeName(pLock->locktype), pLock->cnt , getpid());
  if( CHECK_THREADID(pFile) ) return SQLITE_MISUSE;

  /* If there is already a lock of this type or more restrictive on the
  ** OsFile, do nothing. Don't use the end_lock: exit path, as
  ** sqlite3OsEnterMutex() hasn't been called yet.
  */
  if( pFile->locktype>=locktype ){
    TRACE3("LOCK    %d %s ok (already held)\n", pFile->h,
................................................................................
  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
  assert( locktype!=PENDING_LOCK );
  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );

  /* This mutex is needed because pFile->pLock is shared across threads
  */
  sqlite3OsEnterMutex();









  /* If some thread using this PID has a lock via a different OsFile*
  ** handle that precludes the requested lock, return BUSY.
  */
  if( (pFile->locktype!=pLock->locktype && 
          (pLock->locktype>=PENDING_LOCK || locktype>SHARED_LOCK))
  ){
................................................................................
  struct flock lock;
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;

  assert( pFile );
  TRACE7("UNLOCK  %d %d was %d(%d,%d) pid=%d\n", pFile->h, locktype,
      pFile->locktype, pFile->pLock->locktype, pFile->pLock->cnt, getpid());
  if( CHECK_THREADID(pFile) ) return SQLITE_MISUSE;

  assert( locktype<=SHARED_LOCK );
  if( pFile->locktype<=locktype ){
    return SQLITE_OK;
  }

  sqlite3OsEnterMutex();
  pLock = pFile->pLock;
  assert( pLock->cnt!=0 );
  if( pFile->locktype>SHARED_LOCK ){
    assert( pLock->locktype==pFile->locktype );
    if( locktype==SHARED_LOCK ){
      lock.l_type = F_RDLCK;
................................................................................
}

/*
** Close a file.
*/
static int unixClose(OsFile **pId){
  unixFile *id = (unixFile*)*pId;


  if( !id ) return SQLITE_OK;
  if( CHECK_THREADID(id) ) return SQLITE_MISUSE;
  unixUnlock(*pId, 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
................................................................................
** OsFile.  If we run out of memory, close the file and return NULL.
*/
static int allocateUnixFile(unixFile *pInit, OsFile **pId){
  unixFile *pNew;
  pNew = sqliteMalloc( sizeof(unixFile) );
  if( pNew==0 ){
    close(pInit->h);

    releaseLockInfo(pInit->pLock);
    releaseOpenCnt(pInit->pOpen);

    *pId = 0;
    return SQLITE_NOMEM;
  }else{
    *pNew = *pInit;
    pNew->pMethod = &sqlite3UnixIoMethod;
    *pId = (OsFile*)pNew;
    OpenCounter(+1);

** is first opened.  All subsequent uses of the OsFile verify that the
** same thread is operating on the OsFile.  Some operating systems do
** not allow locks to be overridden by other threads and that restriction
** means that sqlite3* database handles cannot be moved from one thread
** to another.  This logic makes sure a user does not try to do that
** by mistake.
*/
#if defined(SQLITE_UNIX_THREADS)
# define SET_THREADID(X)   (X)->tid = pthread_self()
# define CHECK_THREADID(X) (threadsOverrideEachOthersLocks==0 && \
                            !pthread_equal((X)->tid, pthread_self()))
#else
# define SET_THREADID(X)
# define CHECK_THREADID(X) 0
#endif

/*
** Here is the dirt on POSIX advisory locks:  ANSI STD 1003.1 (1996)
................................................................................
** This variable records whether or not threads can override each others
** locks.
**
**    0:  No.  Threads cannot override each others locks.
**    1:  Yes.  Threads can override each others locks.
**   -1:  We don't know yet.
*/
#ifdef SQLITE_TEST
int threadsOverrideEachOthersLocks = -1;
#else
static int threadsOverrideEachOthersLocks = -1;
#endif

/*
** This structure holds information passed into individual test
** threads by the testThreadLockingBehavior() routine.
*/
struct threadTestData {
  int fd;                /* File to be locked */
................................................................................
}
#endif /* SQLITE_UNIX_THREADS */

/*
** Release a lockInfo structure previously allocated by findLockInfo().
*/
static void releaseLockInfo(struct lockInfo *pLock){
  assert( sqlite3OsInMutex() );
  pLock->nRef--;
  if( pLock->nRef==0 ){
    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
    sqliteFree(pLock);
  }
}

/*
** Release a openCnt structure previously allocated by findLockInfo().
*/
static void releaseOpenCnt(struct openCnt *pOpen){
  assert( sqlite3OsInMutex() );
  pOpen->nRef--;
  if( pOpen->nRef==0 ){
    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
    sqliteFree(pOpen->aPending);
    sqliteFree(pOpen);
  }
}

/*
** Given a file descriptor, locate lockInfo and openCnt structures that
** describes that file descriptor.  Create new ones if necessary.  The
** return values might be uninitialized if an error occurs.
**
** Return the number of errors.
*/
static int findLockInfo(
  int fd,                      /* The file descriptor used in the key */
  struct lockInfo **ppLock,    /* Return the lockInfo structure here */
  struct openCnt **ppOpen      /* Return the openCnt structure here */
................................................................................
  struct openKey key2;
  struct stat statbuf;
  struct lockInfo *pLock;
  struct openCnt *pOpen;
  rc = fstat(fd, &statbuf);
  if( rc!=0 ) return 1;

  assert( sqlite3OsInMutex() );
  memset(&key1, 0, sizeof(key1));
  key1.dev = statbuf.st_dev;
  key1.ino = statbuf.st_ino;
#ifdef SQLITE_UNIX_THREADS
  if( threadsOverrideEachOthersLocks<0 ){
    testThreadLockingBehavior(fd);
  }
................................................................................
      rc = 1;
      goto exit_findlockinfo;
    }
  }else{
    pLock->nRef++;
  }
  *ppLock = pLock;
  if( ppOpen!=0 ){
    pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2));
    if( pOpen==0 ){
      struct openCnt *pOld;
      pOpen = sqliteMallocRaw( sizeof(*pOpen) );
      if( pOpen==0 ){
        releaseLockInfo(pLock);
        rc = 1;
        goto exit_findlockinfo;
      }
      pOpen->key = key2;
      pOpen->nRef = 1;
      pOpen->nLock = 0;
      pOpen->nPending = 0;
      pOpen->aPending = 0;
      pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen);
      if( pOld!=0 ){
        assert( pOld==pOpen );
        sqliteFree(pOpen);
        releaseLockInfo(pLock);
        rc = 1;
        goto exit_findlockinfo;
      }
    }else{
      pOpen->nRef++;
    }
    *ppOpen = pOpen;
  }

exit_findlockinfo:
  return rc;
}

/*
** If we are currently in a different thread than the thread that the
** unixFile argument belongs to, then transfer ownership of the unixFile
** over to the current thread.
**
** A unixFile is only owned by a thread on systems where one thread is
** unable to override locks created by a different thread.  RedHat9 is
** an example of such a system.
**
** Ownership transfer is only allowed if the unixFile is currently unlocked.
** If the unixFile is locked and an ownership is wrong, then return
** SQLITE_MISUSE.  Otherwise return SQLITE_OK.
*/
#ifdef SQLITE_UNIX_THREADS
static int transferOwnership(unixFile *pFile){
  pthread_t hSelf;
  if( threadsOverrideEachOthersLocks ){
    /* Ownership transfers not needed on this system */
    return SQLITE_OK;
  }
  hSelf = pthread_self();
  if( pthread_equal(pFile->tid, hSelf) ){
    /* We are still in the same thread */
    return SQLITE_OK;
  }
  if( pFile->locktype!=NO_LOCK ){
    /* We cannot change ownership while we are holding a lock! */
    return SQLITE_MISUSE;
  }
  pFile->tid = hSelf;
  releaseLockInfo(pFile->pLock);
  return findLockInfo(pFile->h, &pFile->pLock, 0);
}
#else
# define transferOwnership(X) SQLITE_OK
#endif

/*
** Delete the named file
*/
int sqlite3UnixDelete(const char *zFilename){
  unlink(zFilename);
  return SQLITE_OK;
}
................................................................................
** return zero.
*/
static int unixCheckReservedLock(OsFile *id){
  int r = 0;
  unixFile *pFile = (unixFile*)id;

  assert( pFile );

  sqlite3OsEnterMutex(); /* Because pFile->pLock is shared across threads */

  /* Check if a thread in this process holds such a lock */
  if( pFile->pLock->locktype>SHARED_LOCK ){
    r = 1;
  }

................................................................................
  struct flock lock;
  int s;

  assert( pFile );
  TRACE7("LOCK    %d %s was %s(%s,%d) pid=%d\n", pFile->h,
      locktypeName(locktype), locktypeName(pFile->locktype),
      locktypeName(pLock->locktype), pLock->cnt , getpid());


  /* If there is already a lock of this type or more restrictive on the
  ** OsFile, do nothing. Don't use the end_lock: exit path, as
  ** sqlite3OsEnterMutex() hasn't been called yet.
  */
  if( pFile->locktype>=locktype ){
    TRACE3("LOCK    %d %s ok (already held)\n", pFile->h,
................................................................................
  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
  assert( locktype!=PENDING_LOCK );
  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );

  /* This mutex is needed because pFile->pLock is shared across threads
  */
  sqlite3OsEnterMutex();

  /* Make sure the current thread owns the pFile.
  */
  rc = transferOwnership(pFile);
  if( rc!=SQLITE_OK ){
    sqlite3OsLeaveMutex();
    return rc;
  }

  /* If some thread using this PID has a lock via a different OsFile*
  ** handle that precludes the requested lock, return BUSY.
  */
  if( (pFile->locktype!=pLock->locktype && 
          (pLock->locktype>=PENDING_LOCK || locktype>SHARED_LOCK))
  ){
................................................................................
  struct flock lock;
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;

  assert( pFile );
  TRACE7("UNLOCK  %d %d was %d(%d,%d) pid=%d\n", pFile->h, locktype,
      pFile->locktype, pFile->pLock->locktype, pFile->pLock->cnt, getpid());


  assert( locktype<=SHARED_LOCK );
  if( pFile->locktype<=locktype ){
    return SQLITE_OK;
  }
  if( CHECK_THREADID(pFile) ) return SQLITE_MISUSE;
  sqlite3OsEnterMutex();
  pLock = pFile->pLock;
  assert( pLock->cnt!=0 );
  if( pFile->locktype>SHARED_LOCK ){
    assert( pLock->locktype==pFile->locktype );
    if( locktype==SHARED_LOCK ){
      lock.l_type = F_RDLCK;
................................................................................
}

/*
** Close a file.
*/
static int unixClose(OsFile **pId){
  unixFile *id = (unixFile*)*pId;
  int rc;

  if( !id ) return SQLITE_OK;

  rc = unixUnlock(*pId, NO_LOCK);
  if( rc ) return rc;
  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
................................................................................
** OsFile.  If we run out of memory, close the file and return NULL.
*/
static int allocateUnixFile(unixFile *pInit, OsFile **pId){
  unixFile *pNew;
  pNew = sqliteMalloc( sizeof(unixFile) );
  if( pNew==0 ){
    close(pInit->h);
    sqlite3OsEnterMutex();
    releaseLockInfo(pInit->pLock);
    releaseOpenCnt(pInit->pOpen);
    sqlite3OsLeaveMutex();
    *pId = 0;
    return SQLITE_NOMEM;
  }else{
    *pNew = *pInit;
    pNew->pMethod = &sqlite3UnixIoMethod;
    *pId = (OsFile*)pNew;
    OpenCounter(+1);

** or linked into the SQLite library unless you use a non-standard option:
**
**      -DSQLITE_SERVER=1
**
** The configure script will never generate a Makefile with the option
** above.  You will need to manually modify the Makefile if you want to
** include any of the code from this file in your project.  Or, at your
** option, you may want to copy and paste the code from this file and
** thereby avoiding a recompile of SQLite.
**
**
** This source file demonstrates how to use SQLite to create an SQL database 
** server thread in a multiple-threaded program.  One or more client threads
** send messages to the server thread and the server thread processes those
** messages in the order received and returns the results to the client.
................................................................................
**         a thread different from the one where they were created.  With
**         the client/server approach, all database connections are created
**         and used within the server thread.  Client calls to the database
**         can be made from multiple threads (though not at the same time!)
**
**    (2)  Beginning with SQLite version 3.3.0, when two or more 
**         connections to the same database occur within the same thread,
**         they will share their database cache.  This reduces I/O
**         and memory requirements.

**
**    (3)  Database connections on a shared cache use table-level locking
**         instead of file-level locking for improved concurrency.
**
**    (4)  Database connections on a shared cache can by optionally
**         set to READ UNCOMMITTED isolation.  (The default isolation for
**         SQLite is SERIALIZABLE.)  When this occurs, readers will
................................................................................
**       sqlite3_client_reset
**       sqlite3_client_finalize
**       sqlite3_client_close
**
** These interfaces work exactly like the standard core SQLite interfaces
** having the same names without the "_client_" infix.  Many other SQLite
** interfaces can be used directly without having to send messages to the

** server.  The following interfaces fall into this second category:
**
**       sqlite3_bind_*
**       sqlite3_changes
**       sqlite3_clear_bindings
**       sqlite3_column_*
**       sqlite3_complete
**       sqlite3_create_collation
**       sqlite3_create_function
**       sqlite3_data_count
**       sqlite3_db_handle
**       sqlite3_errcode
**       sqlite3_errmsg
**       sqlite3_last_insert_rowid
**       sqlite3_libversion
**       sqlite3_mprintf
**       sqlite3_total_changes
**       sqlite3_transfer_bindings
**       sqlite3_vmprintf
**
** A single SQLite connection (an sqlite3* object) or an SQLite statement
** (an sqlite3_stmt* object) should only be passed to a single interface
** function at a time.  The connections and statements can be freely used
** by any thread as long as only one thread is using them at a time.




**
** The busy handler for all database connections should remain turned
** off.  That means that any lock contention will cause the associated
** sqlite3_client_step() call to return immediately with an SQLITE_BUSY
** error code.  If a busy handler is enabled and lock contention occurs,
** then the entire server thread will block.  This will cause not only
** the requesting client to block but every other database client as
** well.  It is possible to enhance the code below so that lock
** contention will cause the message to be placed back on the top of
** the queue to be tried again later.  But such enhanced processing is
** not included here, in order to keep the example simple.
**
** This code assumes the use of pthreads.  Pthreads implementations
** are available for windows.  (See, for example
** http://sourceware.org/pthreads-win32/announcement.html.)  Or, you
** can translate the locking and thread synchronization code to use
** windows primitives easily enough.  The details are left as an
** exercise to the reader.





















































*/

/*
** Only compile the code in this file on UNIX with a THREADSAFE build
** and only if the SQLITE_SERVER macro is defined.
*/
#ifdef SQLITE_SERVER

** or linked into the SQLite library unless you use a non-standard option:
**
**      -DSQLITE_SERVER=1
**
** The configure script will never generate a Makefile with the option
** above.  You will need to manually modify the Makefile if you want to
** include any of the code from this file in your project.  Or, at your
** option, you may copy and paste the code from this file and
** thereby avoiding a recompile of SQLite.
**
**
** This source file demonstrates how to use SQLite to create an SQL database 
** server thread in a multiple-threaded program.  One or more client threads
** send messages to the server thread and the server thread processes those
** messages in the order received and returns the results to the client.
................................................................................
**         a thread different from the one where they were created.  With
**         the client/server approach, all database connections are created
**         and used within the server thread.  Client calls to the database
**         can be made from multiple threads (though not at the same time!)
**
**    (2)  Beginning with SQLite version 3.3.0, when two or more 
**         connections to the same database occur within the same thread,
**         they can optionally share their database cache.  This reduces
**         I/O and memory requirements.  Cache shared is controlled using
**         the sqlite3_enable_shared_cache() API.
**
**    (3)  Database connections on a shared cache use table-level locking
**         instead of file-level locking for improved concurrency.
**
**    (4)  Database connections on a shared cache can by optionally
**         set to READ UNCOMMITTED isolation.  (The default isolation for
**         SQLite is SERIALIZABLE.)  When this occurs, readers will
................................................................................
**       sqlite3_client_reset
**       sqlite3_client_finalize
**       sqlite3_client_close
**
** These interfaces work exactly like the standard core SQLite interfaces
** having the same names without the "_client_" infix.  Many other SQLite
** interfaces can be used directly without having to send messages to the
** server as long as SQLITE_ENABLE_MEMORY_MANAGEMENT is not defined.
** The following interfaces fall into this second category:
**
**       sqlite3_bind_*
**       sqlite3_changes
**       sqlite3_clear_bindings
**       sqlite3_column_*
**       sqlite3_complete
**       sqlite3_create_collation
**       sqlite3_create_function
**       sqlite3_data_count
**       sqlite3_db_handle
**       sqlite3_errcode
**       sqlite3_errmsg
**       sqlite3_last_insert_rowid


**       sqlite3_total_changes
**       sqlite3_transfer_bindings

**
** A single SQLite connection (an sqlite3* object) or an SQLite statement
** (an sqlite3_stmt* object) should only be passed to a single interface
** function at a time.  The connections and statements can be passed from
** any thread to any of the functions listed in the second group above as
** long as the same connection is not in use by two threads at once and
** as long as SQLITE_ENABLE_MEMORY_MANAGEMENT is not defined.  Additional
** information about the SQLITE_ENABLE_MEMORY_MANAGEMENT constraint is
** below.
**
** The busy handler for all database connections should remain turned
** off.  That means that any lock contention will cause the associated
** sqlite3_client_step() call to return immediately with an SQLITE_BUSY
** error code.  If a busy handler is enabled and lock contention occurs,
** then the entire server thread will block.  This will cause not only
** the requesting client to block but every other database client as
** well.  It is possible to enhance the code below so that lock
** contention will cause the message to be placed back on the top of
** the queue to be tried again later.  But such enhanced processing is
** not included here, in order to keep the example simple.
**
** This example code assumes the use of pthreads.  Pthreads
** implementations are available for windows.  (See, for example
** http://sourceware.org/pthreads-win32/announcement.html.)  Or, you
** can translate the locking and thread synchronization code to use
** windows primitives easily enough.  The details are left as an
** exercise to the reader.
**
**** Restrictions Associated With SQLITE_ENABLE_MEMORY_MANAGEMENT ****
**
** If you compile with SQLITE_ENABLE_MEMORY_MANAGEMENT defined, then
** SQLite includes code that tracks how much memory is being used by
** each thread.  These memory counts can become confused if memory
** is allocated by one thread and then freed by another.  For that
** reason, when SQLITE_ENABLE_MEMORY_MANAGEMENT is used, all operations
** that might allocate or free memory should be performanced in the same
** thread that originally created the database connection.  In that case,
** many of the operations that are listed above as safe to be performed
** in separate threads would need to be sent over to the server to be
** done there.  If SQLITE_ENABLE_MEMORY_MANAGEMENT is defined, then
** the following functions can be used safely from different threads
** without messing up the allocation counts:
**
**       sqlite3_bind_parameter_name
**       sqlite3_bind_parameter_index
**       sqlite3_changes
**       sqlite3_column_blob
**       sqlite3_column_count
**       sqlite3_complete
**       sqlite3_data_count
**       sqlite3_db_handle
**       sqlite3_errcode
**       sqlite3_errmsg
**       sqlite3_last_insert_rowid
**       sqlite3_total_changes
**
** The remaining functions are not thread-safe when memory management
** is enabled.  So one would have to define some new interface routines
** along the following lines:
**
**       sqlite3_client_bind_*
**       sqlite3_client_clear_bindings
**       sqlite3_client_column_*
**       sqlite3_client_create_collation
**       sqlite3_client_create_function
**       sqlite3_client_transfer_bindings
**
** The example code in this file is intended for use with memory
** management turned off.  So the implementation of these additional
** client interfaces is left as an exercise to the reader.
**
** It may seem surprising to the reader that the list of safe functions
** above does not include things like sqlite3_bind_int() or
** sqlite3_column_int().  But those routines might, in fact, allocate
** or deallocate memory.  In the case of sqlite3_bind_int(), if the
** parameter was previously bound to a string that string might need
** to be deallocated before the new integer value is inserted.  In
** the case of sqlite3_column_int(), the value of the column might be
** a UTF-16 string which will need to be converted to UTF-8 then into
** an integer.
*/

/*
** Only compile the code in this file on UNIX with a THREADSAFE build
** and only if the SQLITE_SERVER macro is defined.
*/
#ifdef SQLITE_SERVER

**    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 1.189 2006/01/11 23:40:34 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  extern int sqlite3_sync_count, sqlite3_fullsync_count;
  extern int sqlite3_opentemp_count;
  extern int sqlite3_memUsed;
  extern int sqlite3_malloc_id;
  extern int sqlite3_memMax;
  extern int sqlite3_like_count;
  extern int sqlite3_tsd_count;



#if OS_WIN
  extern int sqlite3_os_type;
#endif
#ifdef SQLITE_DEBUG
  extern int sqlite3_vdbe_addop_trace;
#endif
#ifdef SQLITE_TEST
................................................................................
      (char*)&sqlite3_open_file_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_current_time", 
      (char*)&sqlite3_current_time, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_os_trace",
      (char*)&sqlite3_os_trace, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite3_tsd_count",
      (char*)&sqlite3_tsd_count, TCL_LINK_INT);




#ifndef SQLITE_OMIT_UTF16
  Tcl_LinkVar(interp, "sqlite_last_needed_collation",
      (char*)&pzNeededCollation, TCL_LINK_STRING|TCL_LINK_READ_ONLY);
#endif
#ifdef SQLITE_MEMDEBUG
  Tcl_LinkVar(interp, "sqlite_malloc_id",
      (char*)&sqlite3_malloc_id, TCL_LINK_STRING);

**    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 1.190 2006/01/15 00:13:16 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  extern int sqlite3_sync_count, sqlite3_fullsync_count;
  extern int sqlite3_opentemp_count;
  extern int sqlite3_memUsed;
  extern int sqlite3_malloc_id;
  extern int sqlite3_memMax;
  extern int sqlite3_like_count;
  extern int sqlite3_tsd_count;
#if OS_UNIX && defined(SQLITE_TEST) && defined(THREADSAFE) && THREADSAFE
  extern int threadsOverrideEachOthersLocks;
#endif
#if OS_WIN
  extern int sqlite3_os_type;
#endif
#ifdef SQLITE_DEBUG
  extern int sqlite3_vdbe_addop_trace;
#endif
#ifdef SQLITE_TEST
................................................................................
      (char*)&sqlite3_open_file_count, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_current_time", 
      (char*)&sqlite3_current_time, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_os_trace",
      (char*)&sqlite3_os_trace, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite3_tsd_count",
      (char*)&sqlite3_tsd_count, TCL_LINK_INT);
#if OS_UNIX && defined(SQLITE_TEST) && defined(THREADSAFE) && THREADSAFE
  Tcl_LinkVar(interp, "threadsOverrideEachOthersLocks",
      (char*)&threadsOverrideEachOthersLocks, TCL_LINK_INT);
#endif
#ifndef SQLITE_OMIT_UTF16
  Tcl_LinkVar(interp, "sqlite_last_needed_collation",
      (char*)&pzNeededCollation, TCL_LINK_STRING|TCL_LINK_READ_ONLY);
#endif
#ifdef SQLITE_MEMDEBUG
  Tcl_LinkVar(interp, "sqlite_malloc_id",
      (char*)&sqlite3_malloc_id, TCL_LINK_STRING);

#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is testing the server mode of SQLite.
#
# This file is derived from thread1.test
#
# $Id: server1.test,v 1.3 2006/01/10 20:36:40 drh Exp $


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

# Skip this whole file if the server testing code is not enabled
#
if {[llength [info command client_step]]==0 || [sqlite3 -has-codec]} {
  finish_test
  return
}









# Create some data to work with
#
do_test server1-1.1 {
  execsql {
    CREATE TABLE t1(a,b);
    INSERT INTO t1 VALUES(1,'abcdefgh');

#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is testing the server mode of SQLite.
#
# This file is derived from thread1.test
#
# $Id: server1.test,v 1.4 2006/01/15 00:13:16 drh Exp $


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

# Skip this whole file if the server testing code is not enabled
#
if {[llength [info command client_step]]==0 || [sqlite3 -has-codec]} {
  finish_test
  return
}

# The sample server implementation does not work right when memory
# management is enabled.
#
ifcapable memorymanage {
  finish_test
  return
}

# Create some data to work with
#
do_test server1-1.1 {
  execsql {
    CREATE TABLE t1(a,b);
    INSERT INTO t1 VALUES(1,'abcdefgh');