set blob
}

proc logcksum {ckv1 ckv2 blob} {
  upvar $ckv1 c1
  upvar $ckv2 c2

  binary scan $blob iu* values
  foreach v $values {

    incr c1 $v
    incr c2 $c1
  }

  set c1 [expr ($c1 + ($c1>>24))&0xFFFFFFFF]
  set c2 [expr ($c2 + ($c2>>24))&0xFFFFFFFF]
}
................................................................................
#   3. Using connection 1, checkpoint the database. Make sure all
#      the data is present and the database is not corrupt.
#
# At one point, SQLite was failing to grow the mapping of the wal-index
# file in step 3 and the checkpoint was corrupting the database file.
#
do_test wal-20.1 {

  file delete -force test.db test.db-wal test.db-journal
  sqlite3 db test.db
  execsql {
    PRAGMA journal_mode = WAL;
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES(randomblob(900));
    SELECT count(*) FROM t1;

  set blob
}

proc logcksum {ckv1 ckv2 blob} {
  upvar $ckv1 c1
  upvar $ckv2 c2

  binary scan $blob i* values
  foreach v $values {
    set v [expr {$v & 0xFFFFFFFF}]
    incr c1 $v
    incr c2 $c1
  }

  set c1 [expr ($c1 + ($c1>>24))&0xFFFFFFFF]
  set c2 [expr ($c2 + ($c2>>24))&0xFFFFFFFF]
}
................................................................................
#   3. Using connection 1, checkpoint the database. Make sure all
#      the data is present and the database is not corrupt.
#
# At one point, SQLite was failing to grow the mapping of the wal-index
# file in step 3 and the checkpoint was corrupting the database file.
#
do_test wal-20.1 {
  catch {db close}
  file delete -force test.db test.db-wal test.db-journal
  sqlite3 db test.db
  execsql {
    PRAGMA journal_mode = WAL;
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES(randomblob(900));
    SELECT count(*) FROM t1;

  PRAGMA journal_mode = WAL;
  CREATE TABLE abc(a PRIMARY KEY);
  INSERT INTO abc VALUES(randomblob(1500));
} -sqlbody {
  DELETE FROM abc;
  PRAGMA wal_checkpoint;
}


# A [testvfs] callback for the VFS created by [do_shmfault_test]. This
# callback injects SQLITE_IOERR faults into methods for which an entry
# in array ::shmfault_ioerr_methods is defined. For example, to enable
# errors in xShmOpen:
#
#   set ::shmfault_ioerr_methods(xShmOpen) 1

  PRAGMA journal_mode = WAL;
  CREATE TABLE abc(a PRIMARY KEY);
  INSERT INTO abc VALUES(randomblob(1500));
} -sqlbody {
  DELETE FROM abc;
  PRAGMA wal_checkpoint;
}
catch {db close}

# A [testvfs] callback for the VFS created by [do_shmfault_test]. This
# callback injects SQLITE_IOERR faults into methods for which an entry
# in array ::shmfault_ioerr_methods is defined. For example, to enable
# errors in xShmOpen:
#
#   set ::shmfault_ioerr_methods(xShmOpen) 1

  set sqlite_sync_count 0
  execsql { PRAGMA page_size = 1024 }
  execsql { PRAGMA journal_mode = wal }
} {wal}
do_test walmode-1.2 {
  file size test.db
} {1024}







do_test walmode-1.3 {
  set sqlite_sync_count
} {4}


do_test walmode-1.4 {
  file exists test.db-wal
} {0}
do_test walmode-1.5 {
  execsql { CREATE TABLE t1(a, b) }
  file size test.db
} {1024}

  set sqlite_sync_count 0
  execsql { PRAGMA page_size = 1024 }
  execsql { PRAGMA journal_mode = wal }
} {wal}
do_test walmode-1.2 {
  file size test.db
} {1024}

set expected_sync_count 3
if {$::tcl_platform(platform)!="windows"} {
  ifcapable dirsync {
    incr expected_sync_count
  }
}
do_test walmode-1.3 {
  set sqlite_sync_count

} $expected_sync_count

do_test walmode-1.4 {
  file exists test.db-wal
} {0}
do_test walmode-1.5 {
  execsql { CREATE TABLE t1(a, b) }
  file size test.db
} {1024}