SQLite

  void *zBuf, 
  int iAmt, 
  sqlite_int64 iOfst
){
  MemFile *p = (MemFile *)pFile;
  if( iOfst+iAmt>p->sz ){
    memset(zBuf, 0, iAmt);
    if( iOfst<p->sz ) memcpy(zBuf, p->aData+iOfst, p->sz - iOfst);
    return SQLITE_IOERR_SHORT_READ;
  }
  memcpy(zBuf, p->aData+iOfst, iAmt);
  return SQLITE_OK;
}

/*

  MemFile *p = 0;
  int rc = sqlite3_file_control(db, zSchema, SQLITE_FCNTL_FILE_POINTER, &p);
  if( rc ) return 0;
  if( p->base.pMethods!=&memdb_io_methods ) return 0;
  return p;
}















/*
** Reconfigure a memdb database.
*/
int sqlite3_memdb_config(
  sqlite3 *db,
  const char *zSchema,
  void *aData,

    rc = SQLITE_OK;
  }
  if( rc!=SQLITE_OK && (mFlags & SQLITE_MEMDB_FREEONCLOSE)!=0 ){
    sqlite3_free(aData);
  }
  return SQLITE_OK;
}

/*
** Return the serialization of a database
*/
unsigned char *sqlite3_serialize(
  sqlite3 *db,              /* The database connection */
  const char *zSchema,      /* Which database within the connection */
  sqlite3_int64 *piSize,    /* Write size here, if not NULL */
  unsigned int mFlags       /* Maybe SQLITE_SERIALIZE_NOCOPY */
){
  MemFile *p = memdbFromDbSchema(db, zSchema);
  int iDb = sqlite3FindDbName(db, zSchema);
  Btree *pBt;
  sqlite3_int64 sz;
  int szPage = 0;
  sqlite3_stmt *pStmt = 0;
  unsigned char *pOut;
  char *zSql;
  int rc;

  if( piSize ) *piSize = -1;
  if( iDb<0 ) return 0;
  if( p ){
    if( piSize ) *piSize = p->sz;
    if( mFlags & SQLITE_SERIALIZE_NOCOPY ){
      pOut = p->aData;
    }else{
      pOut = sqlite3_malloc64( p->sz );
      if( pOut ) memcpy(pOut, p->aData, p->sz);
    }
    return pOut;
  }
  pBt = db->aDb[iDb].pBt;
  if( pBt==0 ) return 0;
  szPage = sqlite3BtreeGetPageSize(pBt);
  zSql = sqlite3_mprintf("PRAGMA \"%w\".page_count", zSchema);
  rc = zSql ? sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0) : SQLITE_NOMEM;
  sqlite3_free(zSql);
  if( rc ) return 0;
  sqlite3_step(pStmt);
  sz = sqlite3_column_int64(pStmt, 0)*szPage;
  if( piSize ) *piSize = sz;
  if( mFlags & SQLITE_SERIALIZE_NOCOPY ){
    pOut = 0;
  }else{
    pOut = sqlite3_malloc64( sz );
    if( pOut ){
      int nPage = sqlite3_column_int(pStmt, 0);
      Pager *pPager = sqlite3BtreePager(pBt);
      int pgno;
      for(pgno=1; pgno<=nPage; pgno++){
        DbPage *pPage = 0;
        unsigned char *pTo = pOut + szPage*(sqlite3_int64)(pgno-1);
        rc = sqlite3PagerGet(pPager, pgno, (DbPage**)&pPage, 0);
        if( rc==SQLITE_OK ){
          memcpy(pTo, sqlite3PagerGetData(pPage), szPage);
        }else{
          memset(pTo, 0, szPage);
        }
        sqlite3PagerUnref(pPage);       
      }
    }
  }
  sqlite3_finalize(pStmt);
  return pOut;
}

/* 
** This routine is called when the extension is loaded.
** Register the new VFS.
*/
int sqlite3MemdbInit(void){
  memdb_vfs.pAppData = sqlite3_vfs_find(0);
  memdb_vfs.szOsFile = sizeof(MemFile);
  return sqlite3_vfs_register(&memdb_vfs, 0);
}
#endif /* SQLITE_ENABLE_MEMDB */

** transaction open on the database, or if the database is not a wal mode
** database.
**
** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
*/
SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);

















/*
** CAPI3REF: Set the current MEMDB buffer
** EXPERIMENTAL
**
** This interface is only available when SQLite is compiled
** with SQLITE_ENABLE_MEMDB.
**
** The sqlite3_memdb_config(D,S,P,N,M,F) interface initializes a MEMDB database.
** The database identified by D and S must not be in active use when this
** interface is called, or [SQLITE_BUSY] is returned.
*/
int sqlite3_memdb_config(sqlite3*,const char*,void*,sqlite3_int64,sqlite3_int64,unsigned);

/*
** CAPI3REF: Flags for configuring MEMDB databases
** EXPERIMENTAL
**
** The following are allowed values for the 6th argument (the "flags"
** argument) of the [sqlite3_memdb_config()] interface.
*/
#define SQLITE_MEMDB_FREEONCLOSE  0x001   /* Free the memory buffer on close */
#define SQLITE_MEMDB_RESIZEABLE   0x002   /* Resize using sqlite3_realloc64() */

/*
** CAPI3REF: Serialize a database
** EXPERIMENTAL
**
** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory
** that is a serialization of the S database on [database connection] D.
** If P is not a NULL pointer, then the size of the database in bytes
** is written into *P.
**
** For an ordinary on-disk database file, the serialization is just a
** copy of the disk file.  For an in-memory database or a "TEMP" database,
** the serialization is the same sequence of bytes which would be written
** to disk if that database where backed up to disk.
**
** The usual case is that sqlite3_serialize() copies the serialization of
** the database into memory obtained from [sqlite3_malloc64()] and returns
** a pointer to that memory.  The caller is responsible for freeing the
** returned value to avoid a memory leak.  However, if the F argument
** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
** are made, and the sqlite3_serialize() function will return a pointer
** to the contiguous memory representation of the database that SQLite
** is currently using for that database, or NULL if the no such contiguous
** memory representation of the database exists.  A contigous memory
** representation of the database will usually only exist if there has
** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
** values of D and S.
** The size of the database is written into *P even if the 
** SQLITE_SERIALIZE_NOCOPY bit is set but no contigious copy
** of the database exists.
**
** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
** allocation error occurs.
*/
unsigned char *sqlite3_serialize(
  sqlite3 *db,           /* The database connection */
  const char *zSchema,   /* Which DB to serialize. ex: "main", "temp", ... */
  sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
  unsigned int mFlags    /* Zero or more SQLITE_SERIALIZE_* flags */
);

/*
** CAPI3REF: Flags for sqlite3_serialize
** EXPERIMENTAL
*/
#define SQLITE_SERIALIZE_NOCOPY 0x001   /* Do no memory allocations */

/*
** CAPI3REF: Set the current MEMDB buffer
** EXPERIMENTAL
**
** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 
** [database connection] D to disconnection from database S and then
** reopen S as an in-memory database based on the serialization contained
** in P.  The serialized database P is N bytes in size.  M is the size of
** the buffer P, which might be larger than N.  If M is larger than N, and
** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is
** permitted to add content to the in-memory database as long as the total
** size does not exceed M bytes.
**
** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
** invoke sqlite3_free() on the serialization buffer when the database
** connection closes.  If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
** SQLite will try to increase the buffer size using sqlite3_realloc64()
** if writes on the database cause it to grow larger than M bytes.
**
** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
** database is currently in a read transaction or is involved in a backup
** operation.
**
** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 
** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
** [sqlite3_free()] is invoked on argument P prior to returning.
*/
int sqlite3_deserialize(
  sqlite3 *db,            /* The database connection */
  const char *zSchema,    /* Which DB to reopen with the deserialization */
  unsigned char *pData,   /* The serialized database content */
  sqlite3_int64 szDb,     /* Number bytes in the deserialization */
  sqlite3_int64 szBuf,    /* Total size of buffer pData[] */
  unsigned mFlags         /* Zero or more SQLITE_DESERIALIZE_* flags */
);

/*
** CAPI3REF: Flags for sqlite3_deserialize()
** EXPERIMENTAL
**
** The following are allowed values for the 6th argument (the "flags" or "F"
** argument) of the [sqlite3_deserialize()] interface.
*/
#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
#define SQLITE_DESERIALIZE_RESIZEABLE  2 /* Resize using sqlite3_realloc64() */
#define SQLITE_DESERIALIZE_READONLY    4 /* Database is read-only */

/*
** Undo the hack that converts floating point types to integer for
** builds on processors without floating point support.
*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# undef double

  int objc,
  Tcl_Obj *const*objv
){
  SqliteDb *pDb = (SqliteDb*)cd;
  int choice;
  int rc = TCL_OK;
  static const char *DB_strs[] = {
    "authorizer",             "backup",                "busy",
    "cache",                  "changes",               "close",
    "collate",                "collation_needed",      "commit_hook",
    "complete",               "copy",                  "deserialize",
    "enable_load_extension",  "errorcode",             "eval",
    "exists",                 "function",              "incrblob",
    "interrupt",              "last_insert_rowid",     "memdb",
    "nullvalue",              "onecolumn",             "preupdate",
    "profile",                "progress",              "rekey",
    "restore",                "rollback_hook",         "serialize",
    "status",                 "timeout",               "total_changes",
    "trace",                  "trace_v2",              "transaction",
    "unlock_notify",          "update_hook",           "version",
    "wal_hook",               0                        
  };
  enum DB_enum {
    DB_AUTHORIZER,            DB_BACKUP,               DB_BUSY,
    DB_CACHE,                 DB_CHANGES,              DB_CLOSE,
    DB_COLLATE,               DB_COLLATION_NEEDED,     DB_COMMIT_HOOK,
    DB_COMPLETE,              DB_COPY,                 DB_DESERIALIZE,
    DB_ENABLE_LOAD_EXTENSION, DB_ERRORCODE,            DB_EVAL,
    DB_EXISTS,                DB_FUNCTION,             DB_INCRBLOB,
    DB_INTERRUPT,             DB_LAST_INSERT_ROWID,    DB_MEMDB,
    DB_NULLVALUE,             DB_ONECOLUMN,            DB_PREUPDATE,
    DB_PROFILE,               DB_PROGRESS,             DB_REKEY,
    DB_RESTORE,               DB_ROLLBACK_HOOK,        DB_SERIALIZE,
    DB_STATUS,                DB_TIMEOUT,              DB_TOTAL_CHANGES,
    DB_TRACE,                 DB_TRACE_V2,             DB_TRANSACTION,
    DB_UNLOCK_NOTIFY,         DB_UPDATE_HOOK,          DB_VERSION,
    DB_WAL_HOOK
  };
  /* don't leave trailing commas on DB_enum, it confuses the AIX xlc compiler */

  if( objc<2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "SUBCOMMAND ...");
    return TCL_ERROR;
  }

      sqlite3_snprintf(sizeof(zLineNum), zLineNum,"%d",lineno);
      Tcl_AppendResult(interp,", failed while processing line: ",zLineNum,
                       (char*)0);
      rc = TCL_ERROR;
    }
    break;
  }

  /*
  **     $db deserialize ?DATABASE? VALUE
  **
  ** Reopen DATABASE (default "main") using the content in $VALUE
  */
  case DB_DESERIALIZE: {
    rc = TCL_ERROR;  /* TBD */
    break; 
  }

  /*
  **    $db enable_load_extension BOOLEAN
  **
  ** Turn the extension loading feature on or off.  It if off by
  ** default.
  */

  case DB_MEMDB: {
#ifndef SQLITE_ENABLE_MEMDB
    Tcl_AppendResult(interp, "MEMDB not available in this build",
                     (char*)0);
    rc = TCL_ERROR;
#else
    const char *zSchema = Tcl_GetString(objv[2]);

    unsigned char *pData;
    if( objc==4 ){








      int len = 0, xrc;
      unsigned char *pBA = Tcl_GetByteArrayFromObj(objv[3], &len);
      pData = sqlite3_malloc64( len );
      if( pData==0 ){
        Tcl_AppendResult(interp, "out of memory", (char*)0);
        rc = TCL_ERROR;
      }else{

      Tcl_AppendResult(interp, "restore failed: ",
           sqlite3_errmsg(pDb->db), (char*)0);
      rc = TCL_ERROR;
    }
    sqlite3_close(pSrc);
    break;
  }

  /*
  **     $db serialize ?DATABASE?
  **
  ** Return a serialization of a database.  
  */
  case DB_SERIALIZE: {
#ifndef SQLITE_ENABLE_MEMDB
    Tcl_AppendResult(interp, "MEMDB not available in this build",
                     (char*)0);
    rc = TCL_ERROR;
#else
    const char *zSchema = objc>=3 ? Tcl_GetString(objv[2]) : "main";
    sqlite3_int64 sz = 0;
    unsigned char *pData;
    if( objc!=2 && objc!=3 ){
      Tcl_WrongNumArgs(interp, 2, objv, "?DATABASE?");
      rc = TCL_ERROR;
    }else{
      int needFree;
      pData = sqlite3_serialize(pDb->db, zSchema, &sz, SQLITE_SERIALIZE_NOCOPY);
      if( pData ){
        needFree = 0;
      }else{
        pData = sqlite3_serialize(pDb->db, zSchema, &sz, 0);
        needFree = 1;
      }
      Tcl_SetObjResult(interp, Tcl_NewByteArrayObj(pData,sz));
      if( needFree ) sqlite3_free(pData);
    }
#endif
    break;
  }

  /*
  **     $db status (step|sort|autoindex|vmstep)
  **
  ** Display SQLITE_STMTSTATUS_FULLSCAN_STEP or
  ** SQLITE_STMTSTATUS_SORT for the most recent eval.
  */

}

# Create a MEMDB and populate it with some dummy data.
# Then extract the database into the $::db1 variable.
# Verify that the size of $::db1 is the same as the size of
# the database.
#


unset -nocomplain db1
unset -nocomplain sz1
unset -nocomplain pgsz
do_test 100 {
  db eval {
    CREATE TABLE t1(a,b);
    INSERT INTO t1 VALUES(1,2);
  }
  set ::pgsz [db one {PRAGMA page_size}]
  set ::sz1 [expr {$::pgsz*[db one {PRAGMA page_count}]}]
  set ::db1 [db serialize]
  expr {[string length $::db1]==$::sz1}
} 1
set fd [open db1.db wb]
puts -nonewline $fd $db1
close $fd

# Create a new MEMDB and initialize it to the content of $::db1
# Verify that the content is the same.
#
db close
sqlite3 db -memdb $db1
do_execsql_test 110 {

#!/usr/bin/tclsh
#
# This script is used to generate the array of strings and the enum
# that appear at the beginning of the C code implementation of a
# a TCL command and that define the available subcommands for that
# TCL command.

set prefix {}
while {![eof stdin]} {
  set line [gets stdin]
  if {$line==""} continue
  regsub -all "\[ \t\n,\]+" [string trim $line] { } line
  foreach token [split $line { }] {
    if {![regexp {(([a-zA-Z]+)_)?([_a-zA-Z0-9]+)} $token all px p2 name]} continue
    lappend namelist [string tolower $name]
    if {$px!=""} {set prefix $p2}
  }
}

puts "  static const char *${prefix}_strs\[\] = \173"
set col 0
proc put_item x {
  global col
  if {$col==0} {puts -nonewline "   "}
  if {$col<2} {
    puts -nonewline [format " %-25s" $x]
    incr col
  } else {
    puts $x
    set col 0
  }
}
proc finalize {} {