SQLite

# 2011 July 11
#
# 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 sessions extension.
# Specifically, it tests that sessions work when the database is modified
# using incremental blob handles.
#

if {![info exists testdir]} {
  set testdir [file join [file dirname [info script]] .. .. test]
} 
source [file join [file dirname [info script]] session_common.tcl]
source $testdir/tester.tcl
ifcapable !session {finish_test; return}

set testprefix session6

proc do_then_apply_tcl {tcl {dbname main}} {
  proc xConflict args { return "OMIT" }
  set rc [catch {
    sqlite3session S db $dbname
    db eval "SELECT name FROM $dbname.sqlite_master WHERE type = 'table'" {
      S attach $name
    }
    eval $tcl
    sqlite3changeset_apply db2 [S changeset] xConflict
  } msg]

  catch { S delete }
  if {$rc} {error $msg}
}

test_sqlite3_log x
proc x {args} {puts $args}

forcedelete test.db2
sqlite3 db2 test.db2

do_common_sql {
  CREATE TABLE t1(a PRIMARY KEY, b);
  CREATE TABLE t2(c PRIMARY KEY, d);
}

# Test a blob update.
#
do_test 1.1 {
  do_then_apply_tcl {
    db eval { INSERT INTO t1 VALUES(1, 'helloworld') }
    db eval { INSERT INTO t2 VALUES(2, 'onetwothree') }
  }
  compare_db db db2
} {}
do_test 1.2 {
  do_then_apply_tcl {
    set fd [db incrblob t1 b 1]
    puts -nonewline $fd 1234567890
    close $fd
  }
  compare_db db db2
} {}

# Test an attached database.
#
do_test 2.1 {
  forcedelete test.db3
  file copy test.db2 test.db3
  execsql { ATTACH 'test.db3' AS aux; }

  do_then_apply_tcl {
    set fd [db incrblob aux t2 d 1]
    puts -nonewline $fd fourfivesix
    close $fd
  } aux

  sqlite3 db3 test.db3
  compare_db db2 db3
} {}


db3 close
db2 close

finish_test

#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
/*
** This function is called from within a pre-update callback to retrieve
** the number of columns in the row being updated, deleted or inserted.
*/
int sqlite3_preupdate_count(sqlite3 *db){
  PreUpdate *p = db->pPreUpdate;
  return (p ? p->keyinfo.nField : 0);
}
#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */

#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
/*
** This function is designed to be called from within a pre-update callback
** only. It returns zero if the change that caused the callback was made

  assert( db->pPreUpdate==0 );
  memset(&preupdate, 0, sizeof(PreUpdate));
  if( op==SQLITE_UPDATE ){
    iKey2 = v->aMem[iReg].u.i;
  }else{
    iKey2 = iKey1;
  }

  assert( pCsr->nField==pTab->nCol 
       || (pCsr->nField==pTab->nCol+1 && op==SQLITE_DELETE && iReg==-1)
  );

  preupdate.v = v;
  preupdate.pCsr = pCsr;
  preupdate.op = op;
  preupdate.iNewReg = iReg;
  preupdate.keyinfo.db = db;
  preupdate.keyinfo.enc = ENC(db);
  preupdate.keyinfo.nField = pTab->nCol;
  preupdate.iKey1 = iKey1;
  preupdate.iKey2 = iKey2;
  preupdate.iPKey = pTab->iPKey;

  db->pPreUpdate = &preupdate;
  db->xPreUpdateCallback(db->pPreUpdateArg, db, op, zDb, zTbl, iKey1, iKey2);
  db->pPreUpdate = 0;

  int flags;              /* Copy of "flags" passed to sqlite3_blob_open() */
  int nByte;              /* Size of open blob, in bytes */
  int iOffset;            /* Byte offset of blob in cursor data */
  int iCol;               /* Table column this handle is open on */
  BtCursor *pCsr;         /* Cursor pointing at blob row */
  sqlite3_stmt *pStmt;    /* Statement holding cursor open */
  sqlite3 *db;            /* The associated database */
  char *zDb;              /* Database name */
  Table *pTab;            /* Table object */
};


/*
** This function is used by both blob_open() and blob_reopen(). It seeks
** the b-tree cursor associated with blob handle p to point to row iRow.
** If successful, SQLITE_OK is returned and subsequent calls to

        zErr = pParse->zErrMsg;
        pParse->zErrMsg = 0;
      }
      rc = SQLITE_ERROR;
      sqlite3BtreeLeaveAll(db);
      goto blob_open_out;
    }
    pBlob->pTab = pTab;
    pBlob->zDb = db->aDb[sqlite3SchemaToIndex(db, pTab->pSchema)].zName;

    /* Now search pTab for the exact column. */
    for(iCol=0; iCol<pTab->nCol; iCol++) {
      if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){
        break;
      }
    }

    rc = SQLITE_ABORT;
  }else{
    /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
    ** returned, clean-up the statement handle.
    */
    assert( db == v->db );
    sqlite3BtreeEnterCursor(p->pCsr);

#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
    if( xCall==sqlite3BtreePutData ){
      /* If a pre-update hook is registered and this is a write cursor, 
      ** invoke it here. 
      ** 
      ** TODO: The preupdate-hook is passed SQLITE_DELETE, even though this
      ** operation should really be an SQLITE_UPDATE. This is probably
      ** incorrect, but is convenient because at this point the new.* values 
      ** are not easily obtainable. And for the sessions module, an 
      ** SQLITE_UPDATE where the PK columns do not change is handled in the 
      ** same way as an SQLITE_DELETE (the SQLITE_DELETE code is actually
      ** slightly more efficient). Since you cannot write to a PK column
      ** using the incremental-blob API, this works. For the sessions module
      ** anyhow.
      */
      sqlite3_int64 iKey;
      sqlite3BtreeKeySize(p->pCsr, &iKey);
      sqlite3VdbePreUpdateHook(
          v, v->apCsr[0], SQLITE_DELETE, p->zDb, p->pTab, iKey, -1
      );
    }
#endif

    rc = xCall(p->pCsr, iOffset+p->iOffset, n, z);
    sqlite3BtreeLeaveCursor(p->pCsr);
    if( rc==SQLITE_ABORT ){
      sqlite3VdbeFinalize(v);
      p->pStmt = 0;
    }else{
      db->errCode = rc;