# 2004 September 2

#

# 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 script testing the callback-free C/C++ API and in

# particular the behavior of sqlite3_step() when trying to commit

# with lock contention.

#

# $Id: capi3b.test,v 1.4 2007/08/10 19:46:14 drh Exp $

#

set testdir [file dirname $argv0]

source $testdir/tester.tcl

# These tests depend on the pager holding changes in cache

# until it is time to commit.  But that won't happen if the

# soft-heap-limit is set too low.  So disable the soft heap limit

# for the duration of this test.

#

sqlite3_soft_heap_limit 0

set DB [sqlite3_connection_pointer db]

sqlite3 db2 test.db

set DB2 [sqlite3_connection_pointer db2]

# Create some data in the database

#

do_test capi3b-1.1 {

  execsql {

    CREATE TABLE t1(x);

    INSERT INTO t1 VALUES(1);

    INSERT INTO t1 VALUES(2);

    SELECT * FROM t1

  }

} {1 2}

# Make sure the second database connection can see the data

#

do_test capi3b-1.2 {

  execsql {

    SELECT * FROM t1

  } db2

} {1 2}

# First database connection acquires a shared lock

#

do_test capi3b-1.3 {

  execsql {

    BEGIN;

    SELECT * FROM t1;

  }

} {1 2}

# Second database connection tries to write.  The sqlite3_step()

# function returns SQLITE_BUSY because it cannot commit.

#

do_test capi3b-1.4 {

  set VM [sqlite3_prepare $DB2 {INSERT INTO t1 VALUES(3)} -1 TAIL]

  sqlite3_step $VM

} SQLITE_BUSY

# The sqlite3_step call can be repeated multiple times.

#

do_test capi3b-1.5.1 {

  sqlite3_step $VM

} SQLITE_BUSY

do_test capi3b-1.5.2 {

  sqlite3_step $VM

} SQLITE_BUSY

# The first connection closes its transaction.  This allows the second

# connections sqlite3_step to succeed.

#

do_test capi3b-1.6 {

  execsql COMMIT

  sqlite3_step $VM

} SQLITE_DONE

do_test capi3b-1.7 {

  sqlite3_finalize $VM

} SQLITE_OK

do_test capi3b-1.8 {

  execsql {SELECT * FROM t1} db2

} {1 2 3}

do_test capi3b-1.9 {

  execsql {SELECT * FROM t1}

} {1 2 3}

# Start doing a SELECT with one connection.  This gets a SHARED lock.

# Then do an INSERT with the other connection.  The INSERT should

# not be able to complete until the SELECT finishes.

#

do_test capi3b-2.1 {

  set VM1 [sqlite3_prepare $DB {SELECT * FROM t1} -1 TAIL]

  sqlite3_step $VM1

} SQLITE_ROW

do_test capi3b-2.2 {

  sqlite3_column_text $VM1 0

} 1

do_test capi3b-2.3 {

  set VM2 [sqlite3_prepare $DB2 {INSERT INTO t1 VALUES(4)} -1 TAIL]

  sqlite3_step $VM2

} SQLITE_BUSY

do_test capi3b-2.4 {

  sqlite3_step $VM1

} SQLITE_ROW

do_test capi3b-2.5 {

  sqlite3_column_text $VM1 0

} 2

do_test capi3b-2.6 {

  sqlite3_step $VM2

} SQLITE_BUSY

do_test capi3b-2.7 {

  sqlite3_step $VM1

} SQLITE_ROW

do_test capi3b-2.8 {

  sqlite3_column_text $VM1 0

} 3

do_test capi3b-2.9 {

  sqlite3_step $VM2

} SQLITE_BUSY

do_test capi3b-2.10 {

  sqlite3_step $VM1

} SQLITE_DONE

do_test capi3b-2.11 {

  sqlite3_step $VM2

} SQLITE_DONE

do_test capi3b-2.12 {

  sqlite3_finalize $VM1

  sqlite3_finalize $VM2

  execsql {SELECT * FROM t1}

} {1 2 3 4}

catch {db2 close}

sqlite3_soft_heap_limit $soft_limit

finish_test