# 2010 November 1
#
# 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 testing that WAL databases may be accessed without
# using the xShm primitives if the connection is in exclusive-mode.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix walnoshm
ifcapable !wal {finish_test ; return }

db close
testvfs tvfsshm
testvfs tvfs -default 1 -iversion 1 
sqlite3 db test.db

#--------------------------------------------------------------------------
# Test that when using a version 1 VFS, a database can only be converted
# to WAL mode after setting locking_mode=EXCLUSIVE. Also, test that if a
# WAL database is opened using heap-memory for the WAL index, the connection
# cannot change back to locking_mode=NORMAL while the database is still in
# WAL mode.
#
do_execsql_test 1.1 {
  CREATE TABLE t1(x, y);
  INSERT INTO t1 VALUES(1, 2);
}

do_execsql_test 1.2 { 
  PRAGMA journal_mode = WAL;
  SELECT * FROM t1;
} {delete 1 2}
do_test 1.3 { file exists test.db-wal } {0}

do_execsql_test 1.4 { 
  PRAGMA locking_mode = exclusive;
  PRAGMA journal_mode = WAL;
  SELECT * FROM t1;
} {exclusive wal 1 2}
do_test 1.5 { file exists test.db-wal } {1}

do_execsql_test 1.6 { INSERT INTO t1 VALUES(3, 4) }

do_execsql_test 1.7 {
  PRAGMA locking_mode = normal;
} {exclusive}
do_execsql_test 1.8 {
  PRAGMA journal_mode = delete;
  PRAGMA main.locking_mode;
} {delete exclusive}
do_execsql_test 1.9 {
  PRAGMA locking_mode = normal;
} {normal}
do_execsql_test 1.10 {
  SELECT * FROM t1;
} {1 2 3 4}
do_test 1.11 { file exists test.db-wal } {0}

#-------------------------------------------------------------------------
#
# 2.1.*: Test that a connection using a version 1 VFS can open a WAL database
#        and convert it to rollback mode if it is set to use
#        locking_mode=exclusive.
#
# 2.2.*: Test that if the exclusive lock cannot be obtained while attempting
#        the above, the operation fails and the WAL file is not opened.
#
do_execsql_test 2.1.1 {
  CREATE TABLE t2(x, y);
  INSERT INTO t2 VALUES('a', 'b');
  INSERT INTO t2 VALUES('c', 'd');
}
do_execsql_test 2.1.2 {
  PRAGMA locking_mode = exclusive;
  PRAGMA journal_mode = WAL;
  INSERT INTO t2 VALUES('e', 'f');
  INSERT INTO t2 VALUES('g', 'h');
} {exclusive wal}

do_test 2.1.3 {
  forcecopy test.db     test2.db
  forcecopy test.db-wal test2.db-wal
  sqlite3 db2 test2.db
  catchsql { SELECT * FROM t2 } db2
} {1 {unable to open database file}}
do_test 2.1.4 {
  catchsql { PRAGMA journal_mode = delete } db2
} {1 {unable to open database file}}
do_test 2.1.5 {
  execsql { 
    PRAGMA locking_mode = exclusive; 
    PRAGMA journal_mode = delete;
    SELECT * FROM t2;
  } db2
} {exclusive delete a b c d e f g h}

do_test 2.2.1 {
  forcecopy test.db     test2.db
  forcecopy test.db-wal test2.db-wal
  sqlite3 db3 test2.db -vfs tvfsshm
  sqlite3 db2 test2.db
  execsql { SELECT * FROM t2 } db3
} {a b c d e f g h}

do_test 2.2.2 {
  execsql  { PRAGMA locking_mode = exclusive }  db2
  catchsql { PRAGMA journal_mode = delete } db2
} {1 {database is locked}}

do_test 2.2.3 {
  # This is to test that [db2] is not holding a PENDING lock (which can 
  # happen when an attempt to obtain an EXCLUSIVE lock fails).
  sqlite3 db4 test2.db -vfs tvfsshm
  execsql { SELECT * FROM t2 } db4
} {a b c d e f g h}

do_test 2.2.4 {
  catchsql { SELECT * FROM t2 } db2
} {1 {database is locked}}

do_test 2.2.5 {
  db4 close
  sqlite3 db4 test2.db -vfs tvfsshm
  execsql { SELECT * FROM t2 } db4
} {a b c d e f g h}

do_test 2.2.6 {
  db3 close
  db4 close
  execsql { SELECT * FROM t2 } db2
} {a b c d e f g h}

db2 close
db close

#-------------------------------------------------------------------------
#
# 3.1: Test that if locking_mode=EXCLUSIVE is set after the wal file is
#      opened, it is possible to drop back to locking_mode=NORMAL.
#
# 3.2: Test that if locking_mode=EXCLUSIVE is set before the wal file is
#      opened, it is not.
#
do_test 3.1 {
  sqlite3 db test.db -vfs tvfsshm
  execsql { 
    SELECT * FROM t1;
    PRAGMA locking_mode = EXCLUSIVE;
    INSERT INTO t1 VALUES(5, 6);
    PRAGMA locking_mode = NORMAL;
    INSERT INTO t1 VALUES(7, 8);
  }
  sqlite3 db2 test.db -vfs tvfsshm
  execsql { SELECT * FROM t1 } db2
} {1 2 3 4 5 6 7 8}
db close
db2 close
do_test 3.2 {
  sqlite3 db  test.db -vfs tvfsshm
  execsql { 
    PRAGMA locking_mode = EXCLUSIVE;
    INSERT INTO t1 VALUES(9, 10);
    PRAGMA locking_mode = NORMAL;
    INSERT INTO t1 VALUES(11, 12);
  }
  sqlite3 db2 test.db -vfs tvfsshm
  catchsql { SELECT * FROM t1 } db2
} {1 {database is locked}}
db close
db2 close

tvfs delete
tvfsshm delete

finish_test