SQLite

         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo \
         fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
	 fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo json1.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         memdb.lo memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo parse.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo \
         sqlite3session.lo select.lo sqlite3rbu.lo status.lo stmt.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
         update.lo util.lo vacuum.lo \

  $(TOP)/src/main.c \
  $(TOP)/src/malloc.c \
  $(TOP)/src/mem0.c \
  $(TOP)/src/mem1.c \
  $(TOP)/src/mem2.c \
  $(TOP)/src/mem3.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/memdb.c \
  $(TOP)/src/memjournal.c \
  $(TOP)/src/msvc.h \
  $(TOP)/src/mutex.c \
  $(TOP)/src/mutex.h \
  $(TOP)/src/mutex_noop.c \
  $(TOP)/src/mutex_unix.c \
  $(TOP)/src/mutex_w32.c \

mem3.lo:	$(TOP)/src/mem3.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mem3.c

mem5.lo:	$(TOP)/src/mem5.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mem5.c

memdb.lo:	$(TOP)/src/memdb.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/memdb.c

memjournal.lo:	$(TOP)/src/memjournal.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/memjournal.c

mutex.lo:	$(TOP)/src/mutex.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mutex.c

mutex_noop.lo:	$(TOP)/src/mutex_noop.c $(HDR)

         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
         fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         memdb.lo memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo \
         sqlite3session.lo select.lo sqlite3rbu.lo status.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
         update.lo util.lo vacuum.lo \

  $(TOP)\src\main.c \
  $(TOP)\src\malloc.c \
  $(TOP)\src\mem0.c \
  $(TOP)\src\mem1.c \
  $(TOP)\src\mem2.c \
  $(TOP)\src\mem3.c \
  $(TOP)\src\mem5.c \
  $(TOP)\src\memdb.c \
  $(TOP)\src\memjournal.c \
  $(TOP)\src\mutex.c \
  $(TOP)\src\mutex_noop.c \
  $(TOP)\src\mutex_unix.c \
  $(TOP)\src\mutex_w32.c \
  $(TOP)\src\notify.c \
  $(TOP)\src\os.c \

mem3.lo:	$(TOP)\src\mem3.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\mem3.c

mem5.lo:	$(TOP)\src\mem5.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\mem5.c

memdb.lo:	$(TOP)\src\memjournal.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\memdb.c

memjournal.lo:	$(TOP)\src\memjournal.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\memjournal.c

mutex.lo:	$(TOP)\src\mutex.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\mutex.c

mutex_noop.lo:	$(TOP)\src\mutex_noop.c $(HDR)

         fts3.o fts3_aux.o fts3_expr.o fts3_hash.o fts3_icu.o fts3_porter.o \
         fts3_snippet.o fts3_tokenizer.o fts3_tokenizer1.o \
         fts3_tokenize_vtab.o \
	 fts3_unicode.o fts3_unicode2.o \
         fts3_write.o fts5.o func.o global.o hash.o \
         icu.o insert.o json1.o legacy.o loadext.o \
         main.o malloc.o mem0.o mem1.o mem2.o mem3.o mem5.o \
         memjournal.o \
         memdb.o memjournal.o \
         mutex.o mutex_noop.o mutex_unix.o mutex_w32.o \
         notify.o opcodes.o os.o os_unix.o os_win.o \
         pager.o pcache.o pcache1.o pragma.o prepare.o printf.o \
         random.o resolve.o rowset.o rtree.o \
         select.o sqlite3rbu.o status.o stmt.o \
         table.o threads.o tokenize.o treeview.o trigger.o \
         update.o userauth.o util.o vacuum.o \

  $(TOP)/src/main.c \
  $(TOP)/src/malloc.c \
  $(TOP)/src/mem0.c \
  $(TOP)/src/mem1.c \
  $(TOP)/src/mem2.c \
  $(TOP)/src/mem3.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/memdb.c \
  $(TOP)/src/memjournal.c \
  $(TOP)/src/msvc.h \
  $(TOP)/src/mutex.c \
  $(TOP)/src/mutex.h \
  $(TOP)/src/mutex_noop.c \
  $(TOP)/src/mutex_unix.c \
  $(TOP)/src/mutex_w32.c \

    if( sqlite3GlobalConfig.isPCacheInit==0 ){
      rc = sqlite3PcacheInitialize();
    }
    if( rc==SQLITE_OK ){
      sqlite3GlobalConfig.isPCacheInit = 1;
      rc = sqlite3OsInit();
    }
#ifdef SQLITE_ENABLE_MEMDB
    if( rc==SQLITE_OK ){
      rc = sqlite3MemdbInit();
    }
#endif
    if( rc==SQLITE_OK ){
      sqlite3PCacheBufferSetup( sqlite3GlobalConfig.pPage, 
          sqlite3GlobalConfig.szPage, sqlite3GlobalConfig.nPage);
      sqlite3GlobalConfig.isInit = 1;
#ifdef SQLITE_EXTRA_INIT
      bRunExtraInit = 1;
#endif

  ** been compiled correctly.  It is important to run this code, but
  ** we don't want to run it too often and soak up CPU cycles for no
  ** reason.  So we run it once during initialization.
  */
#ifndef NDEBUG
#ifndef SQLITE_OMIT_FLOATING_POINT
  /* This section of code's only "output" is via assert() statements. */
  if ( rc==SQLITE_OK ){
  if( rc==SQLITE_OK ){
    u64 x = (((u64)1)<<63)-1;
    double y;
    assert(sizeof(x)==8);
    assert(sizeof(x)==sizeof(y));
    memcpy(&y, &x, 8);
    assert( sqlite3IsNaN(y) );
  }

/*
** 2016-09-07
**
** 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 is an in-memory VFS implementation.  The application supplies
** a chunk of memory to hold the database file.
**
** USAGE:
**
**    sqlite3_open_v2("whatever", &db, SQLITE_OPEN_READWRITE, "memdb");
**    void *sqlite3_memdb_ptr(db, "main", &sz);
**    int sqlite3_memdb_config(db, "main", pMem, szData, szMem, mFlags);
**
** Flags:
**
**    SQLITE_MEMDB_FREEONCLOSE        Free pMem when closing the connection
**    SQLITE_MEMDB_RESIZEABLE         Use sqlite3_realloc64() to resize pMem
*/
#ifdef SQLITE_ENABLE_MEMDB
#include "sqliteInt.h"

/*
** Forward declaration of objects used by this utility
*/
typedef struct sqlite3_vfs MemVfs;
typedef struct MemFile MemFile;

/* Access to a lower-level VFS that (might) implement dynamic loading,
** access to randomness, etc.
*/
#define ORIGVFS(p) ((sqlite3_vfs*)((p)->pAppData))

/* An open file */
struct MemFile {
  sqlite3_file base;              /* IO methods */
  sqlite3_int64 sz;               /* Size of the file */
  sqlite3_int64 szMax;            /* Space allocated to aData */
  unsigned char *aData;           /* content of the file */
  int nMmap;                      /* Number of memory mapped pages */
  unsigned mFlags;                /* Flags */
  int eLock;                      /* Most recent lock against this file */
};

/*
** Methods for MemFile
*/
static int memdbClose(sqlite3_file*);
static int memdbRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int memdbWrite(sqlite3_file*,const void*,int iAmt, sqlite3_int64 iOfst);
static int memdbTruncate(sqlite3_file*, sqlite3_int64 size);
static int memdbSync(sqlite3_file*, int flags);
static int memdbFileSize(sqlite3_file*, sqlite3_int64 *pSize);
static int memdbLock(sqlite3_file*, int);
static int memdbCheckReservedLock(sqlite3_file*, int *pResOut);
static int memdbFileControl(sqlite3_file*, int op, void *pArg);
static int memdbSectorSize(sqlite3_file*);
static int memdbDeviceCharacteristics(sqlite3_file*);
static int memdbShmMap(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
static int memdbShmLock(sqlite3_file*, int offset, int n, int flags);
static void memdbShmBarrier(sqlite3_file*);
static int memdbShmUnmap(sqlite3_file*, int deleteFlag);
static int memdbFetch(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
static int memdbUnfetch(sqlite3_file*, sqlite3_int64 iOfst, void *p);

/*
** Methods for MemVfs
*/
static int memdbOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);
static int memdbDelete(sqlite3_vfs*, const char *zName, int syncDir);
static int memdbAccess(sqlite3_vfs*, const char *zName, int flags, int *);
static int memdbFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut);
static void *memdbDlOpen(sqlite3_vfs*, const char *zFilename);
static void memdbDlError(sqlite3_vfs*, int nByte, char *zErrMsg);
static void (*memdbDlSym(sqlite3_vfs *pVfs, void *p, const char*zSym))(void);
static void memdbDlClose(sqlite3_vfs*, void*);
static int memdbRandomness(sqlite3_vfs*, int nByte, char *zOut);
static int memdbSleep(sqlite3_vfs*, int microseconds);
static int memdbCurrentTime(sqlite3_vfs*, double*);
static int memdbGetLastError(sqlite3_vfs*, int, char *);
static int memdbCurrentTimeInt64(sqlite3_vfs*, sqlite3_int64*);

static sqlite3_vfs memdb_vfs = {
  2,                           /* iVersion */
  0,                           /* szOsFile (set when registered) */
  1024,                        /* mxPathname */
  0,                           /* pNext */
  "memdb",                     /* zName */
  0,                           /* pAppData (set when registered) */ 
  memdbOpen,                   /* xOpen */
  memdbDelete,                 /* xDelete */
  memdbAccess,                 /* xAccess */
  memdbFullPathname,           /* xFullPathname */
  memdbDlOpen,                 /* xDlOpen */
  memdbDlError,                /* xDlError */
  memdbDlSym,                  /* xDlSym */
  memdbDlClose,                /* xDlClose */
  memdbRandomness,             /* xRandomness */
  memdbSleep,                  /* xSleep */
  memdbCurrentTime,            /* xCurrentTime */
  memdbGetLastError,           /* xGetLastError */
  memdbCurrentTimeInt64        /* xCurrentTimeInt64 */
};

static const sqlite3_io_methods memdb_io_methods = {
  3,                              /* iVersion */
  memdbClose,                      /* xClose */
  memdbRead,                       /* xRead */
  memdbWrite,                      /* xWrite */
  memdbTruncate,                   /* xTruncate */
  memdbSync,                       /* xSync */
  memdbFileSize,                   /* xFileSize */
  memdbLock,                       /* xLock */
  memdbLock,                       /* xUnlock - same as xLock in this case */ 
  memdbCheckReservedLock,          /* xCheckReservedLock */
  memdbFileControl,                /* xFileControl */
  memdbSectorSize,                 /* xSectorSize */
  memdbDeviceCharacteristics,      /* xDeviceCharacteristics */
  memdbShmMap,                     /* xShmMap */
  memdbShmLock,                    /* xShmLock */
  memdbShmBarrier,                 /* xShmBarrier */
  memdbShmUnmap,                   /* xShmUnmap */
  memdbFetch,                      /* xFetch */
  memdbUnfetch                     /* xUnfetch */
};



/*
** Close an memdb-file.
**
** The pData pointer is owned by the application, so there is nothing
** to free.
*/
static int memdbClose(sqlite3_file *pFile){
  MemFile *p = (MemFile *)pFile;
  if( p->mFlags & SQLITE_MEMDB_FREEONCLOSE ) sqlite3_free(p->aData);
  return SQLITE_OK;
}

/*
** Read data from an memdb-file.
*/
static int memdbRead(
  sqlite3_file *pFile, 
  void *zBuf, 
  int iAmt, 
  sqlite_int64 iOfst
){
  MemFile *p = (MemFile *)pFile;
  if( iOfst+iAmt>p->sz ){
    memset(zBuf, 0, iAmt);
    return SQLITE_IOERR_SHORT_READ;
  }
  memcpy(zBuf, p->aData+iOfst, iAmt);
  return SQLITE_OK;
}

/*
** Try to enlarge the memory allocation to hold at least sz bytes
*/
static int memdbEnlarge(MemFile *p, sqlite3_int64 newSz){
  unsigned char *pNew;
  if( (p->mFlags & SQLITE_MEMDB_RESIZEABLE)==0 ) return SQLITE_FULL;
  if( p->nMmap>0 ) return SQLITE_FULL;
  pNew = sqlite3_realloc64(p->aData, newSz);
  if( pNew==0 ) return SQLITE_FULL;
  p->aData = pNew;
  p->szMax = newSz;
  return SQLITE_OK;
}

/*
** Write data to an memdb-file.
*/
static int memdbWrite(
  sqlite3_file *pFile,
  const void *z,
  int iAmt,
  sqlite_int64 iOfst
){
  MemFile *p = (MemFile *)pFile;
  if( iOfst+iAmt>p->sz ){
    if( iOfst+iAmt>p->szMax && memdbEnlarge(p, (iOfst+iAmt)*2) ){
      return SQLITE_FULL;
    }
    if( iOfst>p->sz ) memset(p->aData+p->sz, 0, iOfst-p->sz);
    p->sz = iOfst+iAmt;
  }
  memcpy(p->aData+iOfst, z, iAmt);
  return SQLITE_OK;
}

/*
** Truncate an memdb-file.
*/
static int memdbTruncate(sqlite3_file *pFile, sqlite_int64 size){
  MemFile *p = (MemFile *)pFile;
  if( size>p->sz ){
    if( size>p->szMax && memdbEnlarge(p, size) ) return SQLITE_FULL;
    memset(p->aData+p->sz, 0, size-p->sz);
  }
  p->sz = size; 
  return SQLITE_OK;
}

/*
** Sync an memdb-file.
*/
static int memdbSync(sqlite3_file *pFile, int flags){
  return SQLITE_OK;
}

/*
** Return the current file-size of an memdb-file.
*/
static int memdbFileSize(sqlite3_file *pFile, sqlite_int64 *pSize){
  MemFile *p = (MemFile *)pFile;
  *pSize = p->sz;
  return SQLITE_OK;
}

/*
** Lock an memdb-file.
*/
static int memdbLock(sqlite3_file *pFile, int eLock){
  MemFile *p = (MemFile *)pFile;
  p->eLock = eLock;
  return SQLITE_OK;
}

/*
** Check if another file-handle holds a RESERVED lock on an memdb-file.
*/
static int memdbCheckReservedLock(sqlite3_file *pFile, int *pResOut){
  *pResOut = 0;
  return SQLITE_OK;
}

/*
** File control method. For custom operations on an memdb-file.
*/
static int memdbFileControl(sqlite3_file *pFile, int op, void *pArg){
  MemFile *p = (MemFile *)pFile;
  int rc = SQLITE_NOTFOUND;
  if( op==SQLITE_FCNTL_VFSNAME ){
    *(char**)pArg = sqlite3_mprintf("memdb(%p,%lld)", p->aData, p->sz);
    rc = SQLITE_OK;
  }
  return rc;
}

/*
** Return the sector-size in bytes for an memdb-file.
*/
static int memdbSectorSize(sqlite3_file *pFile){
  return 1024;
}

/*
** Return the device characteristic flags supported by an memdb-file.
*/
static int memdbDeviceCharacteristics(sqlite3_file *pFile){
  return SQLITE_IOCAP_ATOMIC | 
         SQLITE_IOCAP_POWERSAFE_OVERWRITE |
         SQLITE_IOCAP_SAFE_APPEND |
         SQLITE_IOCAP_SEQUENTIAL;
}

/* Create a shared memory file mapping */
static int memdbShmMap(
  sqlite3_file *pFile,
  int iPg,
  int pgsz,
  int bExtend,
  void volatile **pp
){
  return SQLITE_IOERR_SHMMAP;
}

/* Perform locking on a shared-memory segment */
static int memdbShmLock(sqlite3_file *pFile, int offset, int n, int flags){
  return SQLITE_IOERR_SHMLOCK;
}

/* Memory barrier operation on shared memory */
static void memdbShmBarrier(sqlite3_file *pFile){
  return;
}

/* Unmap a shared memory segment */
static int memdbShmUnmap(sqlite3_file *pFile, int deleteFlag){
  return SQLITE_OK;
}

/* Fetch a page of a memory-mapped file */
static int memdbFetch(
  sqlite3_file *pFile,
  sqlite3_int64 iOfst,
  int iAmt,
  void **pp
){
  MemFile *p = (MemFile *)pFile;
  p->nMmap++;
  *pp = (void*)(p->aData + iOfst);
  return SQLITE_OK;
}

/* Release a memory-mapped page */
static int memdbUnfetch(sqlite3_file *pFile, sqlite3_int64 iOfst, void *pPage){
  MemFile *p = (MemFile *)pFile;
  p->nMmap--;
  return SQLITE_OK;
}

/*
** Open an mem file handle.
*/
static int memdbOpen(
  sqlite3_vfs *pVfs,
  const char *zName,
  sqlite3_file *pFile,
  int flags,
  int *pOutFlags
){
  MemFile *p = (MemFile*)pFile;
  memset(p, 0, sizeof(*p));
  if( (flags & SQLITE_OPEN_MAIN_DB)==0 ) return SQLITE_CANTOPEN;
  p->mFlags = SQLITE_MEMDB_RESIZEABLE | SQLITE_MEMDB_FREEONCLOSE;
  *pOutFlags = flags | SQLITE_OPEN_MEMORY;
  p->base.pMethods = &memdb_io_methods;
  return SQLITE_OK;
}

/*
** Delete the file located at zPath. If the dirSync argument is true,
** ensure the file-system modifications are synced to disk before
** returning.
*/
static int memdbDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  return SQLITE_IOERR_DELETE;
}

/*
** Test for access permissions. Return true if the requested permission
** is available, or false otherwise.
*/
static int memdbAccess(
  sqlite3_vfs *pVfs, 
  const char *zPath, 
  int flags, 
  int *pResOut
){
  *pResOut = 0;
  return SQLITE_OK;
}

/*
** Populate buffer zOut with the full canonical pathname corresponding
** to the pathname in zPath. zOut is guaranteed to point to a buffer
** of at least (INST_MAX_PATHNAME+1) bytes.
*/
static int memdbFullPathname(
  sqlite3_vfs *pVfs, 
  const char *zPath, 
  int nOut, 
  char *zOut
){
  sqlite3_snprintf(nOut, zOut, "%s", zPath);
  return SQLITE_OK;
}

/*
** Open the dynamic library located at zPath and return a handle.
*/
static void *memdbDlOpen(sqlite3_vfs *pVfs, const char *zPath){
  return ORIGVFS(pVfs)->xDlOpen(ORIGVFS(pVfs), zPath);
}

/*
** Populate the buffer zErrMsg (size nByte bytes) with a human readable
** utf-8 string describing the most recent error encountered associated 
** with dynamic libraries.
*/
static void memdbDlError(sqlite3_vfs *pVfs, int nByte, char *zErrMsg){
  ORIGVFS(pVfs)->xDlError(ORIGVFS(pVfs), nByte, zErrMsg);
}

/*
** Return a pointer to the symbol zSymbol in the dynamic library pHandle.
*/
static void (*memdbDlSym(sqlite3_vfs *pVfs, void *p, const char *zSym))(void){
  return ORIGVFS(pVfs)->xDlSym(ORIGVFS(pVfs), p, zSym);
}

/*
** Close the dynamic library handle pHandle.
*/
static void memdbDlClose(sqlite3_vfs *pVfs, void *pHandle){
  ORIGVFS(pVfs)->xDlClose(ORIGVFS(pVfs), pHandle);
}

/*
** Populate the buffer pointed to by zBufOut with nByte bytes of 
** random data.
*/
static int memdbRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  return ORIGVFS(pVfs)->xRandomness(ORIGVFS(pVfs), nByte, zBufOut);
}

/*
** Sleep for nMicro microseconds. Return the number of microseconds 
** actually slept.
*/
static int memdbSleep(sqlite3_vfs *pVfs, int nMicro){
  return ORIGVFS(pVfs)->xSleep(ORIGVFS(pVfs), nMicro);
}

/*
** Return the current time as a Julian Day number in *pTimeOut.
*/
static int memdbCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
  return ORIGVFS(pVfs)->xCurrentTime(ORIGVFS(pVfs), pTimeOut);
}

static int memdbGetLastError(sqlite3_vfs *pVfs, int a, char *b){
  return ORIGVFS(pVfs)->xGetLastError(ORIGVFS(pVfs), a, b);
}
static int memdbCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *p){
  return ORIGVFS(pVfs)->xCurrentTimeInt64(ORIGVFS(pVfs), p);
}

/*
** Translate a database connection pointer and schema name into a
** MemFile pointer.
*/
static MemFile *memdbFromDbSchema(sqlite3 *db, const char *zSchema){
  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;
}

/*
** Return a pointer to the memory used to hold the database.
** Return NULL if the arguments do not describe a memdb database.
*/
void *sqlite3_memdb_ptr(sqlite3 *db, const char *zSchema, sqlite3_int64 *pSz){
  MemFile *p = memdbFromDbSchema(db, zSchema);
  if( p==0 ){
    *pSz = 0;
    return 0;
  }
  *pSz = p->sz;
  return p->aData;
}

/*
** Reconfigure a memdb database.
*/
int sqlite3_memdb_config(
  sqlite3 *db,
  const char *zSchema,
  void *aData,
  sqlite3_int64 sz,
  sqlite3_int64 szMax,
  unsigned int mFlags
){
  MemFile *p = memdbFromDbSchema(db, zSchema);
  if( p==0 ) return SQLITE_ERROR;
  if( p->eLock!=SQLITE_LOCK_NONE || p->nMmap>0 ) return SQLITE_BUSY;
  if( p->mFlags & SQLITE_MEMDB_FREEONCLOSE ) sqlite3_free(p->aData);
  p->aData = aData;
  p->sz = sz;
  p->szMax = szMax;
  p->mFlags = mFlags;
  return SQLITE_OK;
}

/* 
** 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 */

  void (*xReinit)(DbPage*) /* Function to reinitialize pages */
){
  u8 *pPtr;
  Pager *pPager = 0;       /* Pager object to allocate and return */
  int rc = SQLITE_OK;      /* Return code */
  int tempFile = 0;        /* True for temp files (incl. in-memory files) */
  int memDb = 0;           /* True if this is an in-memory file */
  int memJM = 0;           /* Memory journal mode */
  int readOnly = 0;        /* True if this is a read-only file */
  int journalFileSize;     /* Bytes to allocate for each journal fd */
  char *zPathname = 0;     /* Full path to database file */
  int nPathname = 0;       /* Number of bytes in zPathname */
  int useJournal = (flags & PAGER_OMIT_JOURNAL)==0; /* False to omit journal */
  int pcacheSize = sqlite3PcacheSize();       /* Bytes to allocate for PCache */
  u32 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE;  /* Default page size */

  /* Open the pager file.
  */
  if( zFilename && zFilename[0] ){
    int fout = 0;                    /* VFS flags returned by xOpen() */
    rc = sqlite3OsOpen(pVfs, pPager->zFilename, pPager->fd, vfsFlags, &fout);
    assert( !memDb );
    memJM = (fout&SQLITE_OPEN_MEMORY)!=0;
    readOnly = (fout&SQLITE_OPEN_READONLY);
    readOnly = (fout&SQLITE_OPEN_READONLY)!=0;

    /* If the file was successfully opened for read/write access,
    ** choose a default page size in case we have to create the
    ** database file. The default page size is the maximum of:
    **
    **    + SQLITE_DEFAULT_PAGE_SIZE,
    **    + The value returned by sqlite3OsSectorSize()

  /* pPager->pLast = 0; */
  pPager->nExtra = (u16)nExtra;
  pPager->journalSizeLimit = SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT;
  assert( isOpen(pPager->fd) || tempFile );
  setSectorSize(pPager);
  if( !useJournal ){
    pPager->journalMode = PAGER_JOURNALMODE_OFF;
  }else if( memDb ){
  }else if( memDb || memJM ){
    pPager->journalMode = PAGER_JOURNALMODE_MEMORY;
  }
  /* pPager->xBusyHandler = 0; */
  /* pPager->pBusyHandlerArg = 0; */
  pPager->xReiniter = xReinit;
  setGetterMethod(pPager);
  /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */

** sqlite3_snapshot_open(). It is an error if there is already a read
** 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: Retrieve the current MEMDB buffer
** EXPERIMENTAL
**
** This interface is only available when SQLite is compiled
** with SQLITE_ENABLE_MEMDB.
**
** The sqlite3_memdb_ptr(D,S,P) interface returns a pointer to the
** memory buffer that is the database file used for [database connection] D
** and schema S.  If schema S of database connection D is not a MEMDB
** database, then this routine returns NULL.  If P is not NULL, then it must
** be a pointer to a 64-bit signed integer into which the size of the 
** database file is written.
*/
SQLITE_EXPERIMENTAL void *sqlite3_memdb_ptr(sqlite3*,const char*,sqlite3_int64*);

/*
** 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.
*/
SQLITE_EXPERIMENTAL 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() */


/*
** 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

void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
u8 sqlite3HexToInt(int h);
int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);

#if defined(SQLITE_NEED_ERR_NAME)
const char *sqlite3ErrName(int);
#endif

#ifdef SQLITE_ENABLE_MEMDB
int sqlite3MemdbInit(void);
#endif

const char *sqlite3ErrStr(int);
int sqlite3ReadSchema(Parse *pParse);
CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, Expr *pExpr);

  static const char *DB_strs[] = {
    "authorizer",         "backup",            "busy",
    "cache",              "changes",           "close",
    "collate",            "collation_needed",  "commit_hook",
    "complete",           "copy",              "enable_load_extension",
    "errorcode",          "eval",              "exists",
    "function",           "incrblob",          "interrupt",
    "last_insert_rowid",  "nullvalue",         "onecolumn",
    "preupdate",          "profile",           "progress",
    "rekey",              "restore",           "rollback_hook",
    "status",             "timeout",           "total_changes",
    "trace",              "trace_v2",          "transaction",
    "unlock_notify",      "update_hook",       "version",
    "wal_hook",
    "last_insert_rowid",  "memdb",             "nullvalue",
    "onecolumn",          "preupdate",         "profile",
    "progress",           "rekey",             "restore",
    "rollback_hook",      "status",            "timeout",
    "total_changes",      "trace",             "trace_v",
    "transaction",        "unlock_notify",     "update_hook",
    "version",            "wal_hook",          0
    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_ENABLE_LOAD_EXTENSION,
    DB_ERRORCODE,         DB_EVAL,             DB_EXISTS,
    DB_FUNCTION,          DB_INCRBLOB,         DB_INTERRUPT,
    DB_LAST_INSERT_ROWID, DB_NULLVALUE,        DB_ONECOLUMN,
    DB_PREUPDATE,         DB_PROFILE,          DB_PROGRESS,
    DB_REKEY,             DB_RESTORE,          DB_ROLLBACK_HOOK,
    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,
    DB_LAST_INSERT_ROWID, DB_MEMDB,            DB_NULLVALUE,
    DB_ONECOLUMN,         DB_PREUPDATE,        DB_PROFILE,
    DB_PROGRESS,          DB_REKEY,            DB_RESTORE,
    DB_ROLLBACK_HOOK,     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;
  }

  ** Interrupt the execution of the inner-most SQL interpreter.  This
  ** causes the SQL statement to return an error of SQLITE_INTERRUPT.
  */
  case DB_INTERRUPT: {
    sqlite3_interrupt(pDb->db);
    break;
  }

  /*
  **     $db memdb DATABASE ?BLOB?
  **
  ** Set or query the content of a MEMDB database.
  **
  */
  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]);
    sqlite3_int64 sz = 0;
    unsigned char *pData;
    if( objc==3 ){
      pData = sqlite3_memdb_ptr(pDb->db, zSchema, &sz);
      if( pData==0 ){
        Tcl_AppendResult(interp, "not a MEMDB database", (char*)0);
        rc = TCL_ERROR;
      }else{
        Tcl_SetObjResult(interp, Tcl_NewByteArrayObj(pData,sz));
      }
    }else 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{
        memcpy(pData, pBA, len);
        xrc = sqlite3_memdb_config(pDb->db, zSchema, pData, len, len,
                  SQLITE_MEMDB_FREEONCLOSE|SQLITE_MEMDB_RESIZEABLE);
        if( xrc ){
          sqlite3_free(pData);
          Tcl_AppendResult(interp, "unable to set MEMDB content", (char*)0);
          rc = TCL_ERROR;
        }
      }
    }else{
      Tcl_WrongNumArgs(interp, 2, objv, "?SCRIPT?");
      rc = TCL_ERROR;
    }
#endif
    break;
  }

  /*
  **     $db nullvalue ?STRING?
  **
  ** Change text used when a NULL comes back from the database. If ?STRING?
  ** is not present, then the current string used for NULL is returned.
  ** If STRING is present, then STRING is returned.

#endif

#ifdef SQLITE_ENABLE_HIDDEN_COLUMNS
  Tcl_SetVar2(interp, "sqlite_options", "hiddencolumns", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "hiddencolumns", "0", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_ENABLE_MEMDB
  Tcl_SetVar2(interp, "sqlite_options", "memdb", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "memdb", "0", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_ENABLE_MEMSYS3
  Tcl_SetVar2(interp, "sqlite_options", "mem3", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "mem3", "0", TCL_GLOBAL_ONLY);
#endif

# 2018-01-02
#
# 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 implements regression tests for SQLite library.  The
# focus of this file is the "memdb" VFS
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix memdb1
do_not_use_codec

ifcapable !memdb {
  finish_test
  return
}

# Create a MEMDB and populate it with some dummy data.
# Then extract the database into the $::db1 variable.
# Verify that the size of $::db1 is the same as the size of
# the database.
#
db close
sqlite3 db dummy -vfs memdb
unset -nocomplain db1
unset -nocomplain sz1
unset -nocomplain pgsz
do_test 100 {
  db eval {
    CREATE TABLE t1(a,b);
    INSERT INTO t1 VALUES(1,2);
  }
  set ::pgsz [db one {PRAGMA page_size}]
  set ::sz1 [expr {$::pgsz*[db one {PRAGMA page_count}]}]
  set ::db1 [db memdb main]
  expr {[string length $::db1]==$::sz1}
} 1

# Create a new MEMDB and initialize it to the content of $::db1
# Verify that the content is the same.
#
db close
sqlite3 db dummy2 -vfs memdb
db memdb main $db1
do_execsql_test 110 {
  SELECT * FROM t1;
} {1 2}


finish_test

   utf.c
   util.c
   hash.c
   opcodes.c

   os_unix.c
   os_win.c
   memdb.c

   bitvec.c
   pcache.c
   pcache1.c
   rowset.c
   pager.c
   wal.c