SQLite

    zShmFilename = pShmNode->zFilename = (char*)&pShmNode[1];
#ifdef SQLITE_SHM_DIRECTORY
    sqlite3_snprintf(nShmFilename, zShmFilename, 
                     SQLITE_SHM_DIRECTORY "/sqlite-shm-%x-%x",
                     (u32)sStat.st_ino, (u32)sStat.st_dev);
#else
    sqlite3_snprintf(nShmFilename, zShmFilename, "%s-shm", pDbFd->zPath);
    sqlite3FileSuffix3(pDbFd->zPath, zShmFilename);
#endif
    pShmNode->h = -1;
    pDbFd->pInode->pShmNode = pShmNode;
    pShmNode->pInode = pDbFd->pInode;
    pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
    if( pShmNode->mutex==0 ){
      rc = SQLITE_NOMEM;

** mask SQLITE_DEFAULT_FILE_PERMISSIONS.
**
** Finally, if the file being opened is a WAL or regular journal file, then 
** this function queries the file-system for the permissions on the 
** corresponding database file and sets *pMode to this value. Whenever 
** possible, WAL and journal files are created using the same permissions 
** as the associated database file.
**
** If the SQLITE_ENABLE_8_3_NAMES option is enabled, then the
** original filename is unavailable.  But 8_3_NAMES is only used for
** FAT filesystems and permissions do not matter there, so just use
** the default permissions.
*/
static int findCreateFileMode(
  const char *zPath,              /* Path of file (possibly) being created */
  int flags,                      /* Flags passed as 4th argument to xOpen() */
  mode_t *pMode                   /* OUT: Permissions to open file with */
){
  int rc = SQLITE_OK;             /* Return Code */
  *pMode = SQLITE_DEFAULT_FILE_PERMISSIONS;
  if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
    char zDb[MAX_PATHNAME+1];     /* Database file path */
    int nDb;                      /* Number of valid bytes in zDb */
    struct stat sStat;            /* Output of stat() on database file */

    /* zPath is a path to a WAL or journal file. The following block derives
    ** the path to the associated database file from zPath. This block handles
    ** the following naming conventions:
    **
    **   "<path to db>-journal"
    **   "<path to db>-wal"
    **   "<path to db>-journalNN"
    **   "<path to db>-walNN"
    **
    ** where NN is a 4 digit decimal number. The NN naming schemes are 
    ** used by the test_multiplex.c module.
    */
    nDb = sqlite3Strlen30(zPath) - 1; 
    while( nDb>0 && zPath[nDb]!='-' ) nDb--;
    if( nDb==0 ) return SQLITE_OK;
    memcpy(zDb, zPath, nDb);
    zDb[nDb] = '\0';

    if( 0==stat(zDb, &sStat) ){
      *pMode = sStat.st_mode & 0777;
    }else{
      rc = SQLITE_IOERR_FSTAT;
    }
  }else if( flags & SQLITE_OPEN_DELETEONCLOSE ){
    *pMode = 0600;


  }
  return rc;
}

/*
** Open the file zPath.
** 

  if( pNew==0 ){
    sqlite3_free(p);
    return SQLITE_NOMEM;
  }
  memset(pNew, 0, sizeof(*pNew));
  pNew->zFilename = (char*)&pNew[1];
  sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
  sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename); 

  /* Look to see if there is an existing winShmNode that can be used.
  ** If no matching winShmNode currently exists, create a new one.
  */
  winShmEnterMutex();
  for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){
    /* TBD need to come up with better match here.  Perhaps

  if( zPathname ){
    assert( nPathname>0 );
    pPager->zJournal =   (char*)(pPtr += nPathname + 1 + nUri);
    memcpy(pPager->zFilename, zPathname, nPathname);
    memcpy(&pPager->zFilename[nPathname+1], zUri, nUri);
    memcpy(pPager->zJournal, zPathname, nPathname);
    memcpy(&pPager->zJournal[nPathname], "-journal", 8);
    sqlite3FileSuffix3(pPager->zFilename, pPager->zJournal);
#ifndef SQLITE_OMIT_WAL
    pPager->zWal = &pPager->zJournal[nPathname+8+1];
    memcpy(pPager->zWal, zPathname, nPathname);
    memcpy(&pPager->zWal[nPathname], "-wal", 4);
    sqlite3FileSuffix3(pPager->zFilename, pPager->zWal);
#endif
    sqlite3_free(zPathname);
  }
  pPager->pVfs = pVfs;
  pPager->vfsFlags = vfsFlags;

  /* Open the pager file.

  }
  return 1;
}

/*
** Interpret the given string as a boolean value.
*/
u8 sqlite3GetBoolean(const char *z){
  return getSafetyLevel(z)&1;
}

/*
** Interpret the given string as a locking mode value.
*/
static int getLockingMode(const char *z){

          int mask = p->mask;          /* Mask of bits to set or clear. */
          if( db->autoCommit==0 ){
            /* Foreign key support may not be enabled or disabled while not
            ** in auto-commit mode.  */
            mask &= ~(SQLITE_ForeignKeys);
          }

          if( sqlite3GetBoolean(zRight) ){
            db->flags |= mask;
          }else{
            db->flags &= ~mask;
          }

          /* Many of the flag-pragmas modify the code generated by the SQL 
          ** compiler (eg. count_changes). So add an opcode to expire all

  ** flag setting and reports thenew value.
  */
  if( sqlite3StrICmp(zLeft,"secure_delete")==0 ){
    Btree *pBt = pDb->pBt;
    int b = -1;
    assert( pBt!=0 );
    if( zRight ){
      b = sqlite3GetBoolean(zRight);
    }
    if( pId2->n==0 && b>=0 ){
      int ii;
      for(ii=0; ii<db->nDb; ii++){
        sqlite3BtreeSecureDelete(db->aDb[ii].pBt, b);
      }
    }

    }
  }else
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */

#ifndef NDEBUG
  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
    if( zRight ){
      if( sqlite3GetBoolean(zRight) ){
        sqlite3ParserTrace(stderr, "parser: ");
      }else{
        sqlite3ParserTrace(0, 0);
      }
    }
  }else
#endif

  /* Reinstall the LIKE and GLOB functions.  The variant of LIKE
  ** used will be case sensitive or not depending on the RHS.
  */
  if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
    if( zRight ){
      sqlite3RegisterLikeFunctions(db, sqlite3GetBoolean(zRight));
    }
  }else

#ifndef SQLITE_INTEGRITY_CHECK_ERROR_MAX
# define SQLITE_INTEGRITY_CHECK_ERROR_MAX 100
#endif

int sqlite3CheckCollSeq(Parse *, CollSeq *);
int sqlite3CheckObjectName(Parse *, const char *);
void sqlite3VdbeSetChanges(sqlite3 *, int);
int sqlite3AddInt64(i64*,i64);
int sqlite3SubInt64(i64*,i64);
int sqlite3MulInt64(i64*,i64);
int sqlite3AbsInt32(int);
#ifdef SQLITE_ENABLE_8_3_NAMES
void sqlite3FileSuffix3(const char*, char*);
#else
# define sqlite3FileSuffix3(X,Y)
#endif
u8 sqlite3GetBoolean(const char *z);

const void *sqlite3ValueText(sqlite3_value*, u8);
int sqlite3ValueBytes(sqlite3_value*, u8);
void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8, 
                        void(*)(void*));
void sqlite3ValueFree(sqlite3_value*);
sqlite3_value *sqlite3ValueNew(sqlite3 *);

#endif

#if 1 /* def SQLITE_MEMDEBUG */
  Tcl_SetVar2(interp, "sqlite_options", "memdebug", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "memdebug", "0", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_ENABLE_8_3_NAMES
  Tcl_SetVar2(interp, "sqlite_options", "8_3_names", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "8_3_names", "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

** if the integer has a value of -2147483648, return +2147483647
*/
int sqlite3AbsInt32(int x){
  if( x>=0 ) return x;
  if( x==(int)0x80000000 ) return 0x7fffffff;
  return -x;
}

#ifdef SQLITE_ENABLE_8_3_NAMES
/*
** If SQLITE_ENABLE_8_3_NAME is set at compile-time and if the database
** filename in zBaseFilename is a URI with the "8_3_names=1" parameter and
** if filename in z[] has a suffix (a.k.a. "extension") that is longer than
** three characters, then shorten the suffix on z[] to be the last three
** characters of the original suffix.
**
** Examples:
**
**     test.db-journal    =>   test.nal
**     test.db-wal        =>   test.wal
**     test.db-shm        =>   test.shm
*/
void sqlite3FileSuffix3(const char *zBaseFilename, char *z){
  const char *zOk;
  zOk = sqlite3_uri_parameter(zBaseFilename, "8_3_names");
  if( zOk && sqlite3GetBoolean(zOk) ){
    int i, sz;
    sz = sqlite3Strlen30(z);
    for(i=sz-1; i>0 && z[i]!='/' && z[i]!='\\' && z[i]!='.'; i--){}
    if( z[i]=='.' && sz>i+4 ) memcpy(&z[i+1], &z[sz-3], 4);
  }
}
#endif

      u32 iRandom;
      sqlite3DbFree(db, zMaster);
      sqlite3_randomness(sizeof(iRandom), &iRandom);
      zMaster = sqlite3MPrintf(db, "%s-mj%08X", zMainFile, iRandom&0x7fffffff);
      if( !zMaster ){
        return SQLITE_NOMEM;
      }
      sqlite3FileSuffix3(zMainFile, zMaster);
      rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
    }while( rc==SQLITE_OK && res );
    if( rc==SQLITE_OK ){
      /* Open the master journal. */
      rc = sqlite3OsOpenMalloc(pVfs, zMaster, &pMaster, 
          SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
          SQLITE_OPEN_EXCLUSIVE|SQLITE_OPEN_MASTER_JOURNAL, 0

# 2011 May 17
#
# 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.
#
#***********************************************************************
#
# Test cases for the SQLITE_ENABLE_8_3_NAMES feature that forces all
# filename extensions to be limited to 3 characters.  Some embedded
# systems need this to work around microsoft FAT patents, but this
# feature should be disabled on most deployments.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
ifcapable !8_3_names {
  finish_test
  return
}

db close
sqlite3_shutdown
sqlite3_config_uri 1

do_test 8_3_names-1.0 {
  forcedelete test.db test.nal test.db-journal
  sqlite3 db test.db
  db eval {
    PRAGMA cache_size=10;
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES(randomblob(20000));
    BEGIN;
    DELETE FROM t1;
    INSERT INTO t1 VALUES(randomblob(15000));
  }
  file exists test.db-journal
} 1
do_test 8_3_names-1.1 {
  file exists test.nal
} 0
do_test 8_3_names-1.2 {
  db eval {
    ROLLBACK;
    SELECT length(x) FROM t1
  }
} 20000

db close
do_test 8_3_names-2.0 {
  forcedelete test.db test.nal test.db-journal
  sqlite3 db file:./test.db?8_3_names=1
  db eval {
    PRAGMA cache_size=10;
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES(randomblob(20000));
    BEGIN;
    DELETE FROM t1;
    INSERT INTO t1 VALUES(randomblob(15000));
  }
  file exists test.db-journal
} 0
do_test 8_3_names-2.1 {
  file exists test.nal
} 1
forcedelete test2.db test2.nal test2.db-journal
file copy test.db test2.db
file copy test.nal test2.nal
do_test 8_3_names-2.2 {
  db eval {
    COMMIT;
    SELECT length(x) FROM t1
  }
} 15000
do_test 8_3_names-2.3 {
  sqlite3 db2 file:./test2.db?8_3_names=1
  db2 eval {
    PRAGMA integrity_check;
    SELECT length(x) FROM t1;
  }
} {ok 20000}

db close
do_test 8_3_names-3.0 {
  forcedelete test.db test.nal test.db-journal
  sqlite3 db file:./test.db?8_3_names=0
  db eval {
    PRAGMA cache_size=10;
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES(randomblob(20000));
    BEGIN;
    DELETE FROM t1;
    INSERT INTO t1 VALUES(randomblob(15000));
  }
  file exists test.db-journal
} 1
do_test 8_3_names-3.1 {
  file exists test.nal
} 0
forcedelete test2.db test2.nal test2.db-journal
file copy test.db test2.db
file copy test.db-journal test2.db-journal
do_test 8_3_names-3.2 {
  db eval {
    COMMIT;
    SELECT length(x) FROM t1
  }
} 15000
do_test 8_3_names-3.3 {
  sqlite3 db2 file:./test2.db?8_3_names=0
  db2 eval {
    PRAGMA integrity_check;
    SELECT length(x) FROM t1;
  }
} {ok 20000}

##########################################################################
# Master journals.
#
db close
forcedelete test.db test2.db
do_test 8_3_names-4.0 {
  sqlite3 db file:./test.db?8_3_names=1
  db eval {
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES(1);
    ATTACH 'file:./test2.db?8_3_names=1' AS db2;
    CREATE TABLE db2.t2(y);
    INSERT INTO t2 VALUES(2);
    BEGIN;
      INSERT INTO t1 VALUES(3);
      INSERT INTO t2 VALUES(4);
    COMMIT;
    SELECT * FROM t1, t2 ORDER BY x, y
  }
} {1 2 1 4 3 2 3 4}
    

##########################################################################
# WAL mode.
#
ifcapable !wal {
  finish_test
  return
}
db close
forcedelete test.db
do_test 8_3_names-5.0 {
  sqlite3 db file:./test.db?8_3_names=1
  register_wholenumber_module db
  db eval {
    PRAGMA journal_mode=WAL;
    CREATE TABLE t1(x);
    CREATE VIRTUAL TABLE nums USING wholenumber;
    INSERT INTO t1 SELECT value FROM nums WHERE value BETWEEN 1 AND 1000;
    BEGIN;
    UPDATE t1 SET x=x*2;
  }
  sqlite3 db2 file:./test.db?8_3_names=1
  register_wholenumber_module db2
  db2 eval {
    BEGIN;
    SELECT sum(x) FROM t1;
  }
} {500500}

do_test 8_3_names-5.1 {
  file exists test.db-wal
} 0
do_test 8_3_names-5.2 {
  file exists test.wal
} 1
do_test 8_3_names-5.3 {
  file exists test.db-shm
} 0
do_test 8_3_names-5.4 {
  file exists test.shm
} 1


do_test 8_3_names-5.5 {
  db eval {
    COMMIT;
    SELECT sum(x) FROM t1;
  }
} {1001000}
do_test 8_3_names-5.6 {
  db2 eval {
    SELECT sum(x) FROM t1;
  }
} {500500}


finish_test