| Index: third_party/sqlite/test/thread005.test
|
| ===================================================================
|
| --- third_party/sqlite/test/thread005.test (revision 56608)
|
| +++ third_party/sqlite/test/thread005.test (working copy)
|
| @@ -1,238 +0,0 @@
|
| -# 2009 March 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.
|
| -#
|
| -#***********************************************************************
|
| -#
|
| -# Test a race-condition that shows up in shared-cache mode.
|
| -#
|
| -# $Id: thread005.test,v 1.5 2009/03/26 14:48:07 danielk1977 Exp $
|
| -
|
| -set testdir [file dirname $argv0]
|
| -
|
| -source $testdir/tester.tcl
|
| -if {[run_thread_tests]==0} { finish_test ; return }
|
| -ifcapable !shared_cache {
|
| - finish_test
|
| - return
|
| -}
|
| -
|
| -db close
|
| -
|
| -# Use shared-cache mode for these tests.
|
| -#
|
| -set ::enable_shared_cache [sqlite3_enable_shared_cache]
|
| -sqlite3_enable_shared_cache 1
|
| -
|
| -#-------------------------------------------------------------------------
|
| -# This test attempts to hit the race condition fixed by commit [6363].
|
| -#
|
| -proc runsql {zSql {db {}}} {
|
| - set rc SQLITE_OK
|
| - while {$rc=="SQLITE_OK" && $zSql ne ""} {
|
| - set STMT [sqlite3_prepare_v2 $db $zSql -1 zSql]
|
| - while {[set rc [sqlite3_step $STMT]] eq "SQLITE_ROW"} { }
|
| - set rc [sqlite3_finalize $STMT]
|
| - }
|
| - return $rc
|
| -}
|
| -do_test thread005-1.1 {
|
| - sqlite3 db test.db
|
| - db eval { CREATE TABLE t1(a, b) }
|
| - db close
|
| -} {}
|
| -for {set ii 2} {$ii < 500} {incr ii} {
|
| - unset -nocomplain finished
|
| - thread_spawn finished(0) {sqlite3_open test.db}
|
| - thread_spawn finished(1) {sqlite3_open test.db}
|
| - if {![info exists finished(0)]} { vwait finished(0) }
|
| - if {![info exists finished(1)]} { vwait finished(1) }
|
| -
|
| - do_test thread005-1.$ii {
|
| - runsql { BEGIN } $finished(0)
|
| - runsql { INSERT INTO t1 VALUES(1, 2) } $finished(0)
|
| -
|
| - # If the race-condition was hit, then $finished(0 and $finished(1)
|
| - # will not use the same pager cache. In this case the next statement
|
| - # can be executed succesfully. However, if the race-condition is not
|
| - # hit, then $finished(1) will be blocked by the write-lock held by
|
| - # $finished(0) on the shared-cache table t1 and the statement will
|
| - # return SQLITE_LOCKED.
|
| - #
|
| - runsql { SELECT * FROM t1 } $finished(1)
|
| - } {SQLITE_LOCKED}
|
| -
|
| - sqlite3_close $finished(0)
|
| - sqlite3_close $finished(1)
|
| -}
|
| -
|
| -
|
| -#-------------------------------------------------------------------------
|
| -# This test tries to exercise a race-condition that existed in shared-cache
|
| -# mode at one point. The test uses two threads; each has a database connection
|
| -# open on the same shared cache. The schema of the database is:
|
| -#
|
| -# CREATE TABLE t1(a INTEGER PRIMARY KEY, b UNIQUE);
|
| -#
|
| -# One thread is a reader and the other thread a reader and a writer. The
|
| -# writer thread repeats the following transaction as fast as possible:
|
| -#
|
| -# BEGIN;
|
| -# DELETE FROM t1 WHERE a = (SELECT max(a) FROM t1);
|
| -# INSERT INTO t1 VALUES(NULL, NULL);
|
| -# UPDATE t1 SET b = a WHERE a = (SELECT max(a) FROM t1);
|
| -# SELECT count(*) FROM t1 WHERE b IS NULL;
|
| -# COMMIT;
|
| -#
|
| -# The reader thread does the following over and over as fast as possible:
|
| -#
|
| -# BEGIN;
|
| -# SELECT count(*) FROM t1 WHERE b IS NULL;
|
| -# COMMIT;
|
| -#
|
| -# The test runs for 20 seconds or until one of the "SELECT count(*)"
|
| -# statements returns a non-zero value. If an SQLITE_LOCKED error occurs,
|
| -# the connection issues a ROLLBACK immediately to abandon the current
|
| -# transaction.
|
| -#
|
| -# If everything is working correctly, the "SELECT count(*)" statements
|
| -# should never return a value other than 0. The "INSERT" statement
|
| -# executed by the writer adds a row with "b IS NULL" to the table, but
|
| -# the subsequent UPDATE statement sets its "b" value to an integer
|
| -# immediately afterwards.
|
| -#
|
| -# However, before the race-condition was fixed, if the reader's SELECT
|
| -# statement hit an error (say an SQLITE_LOCKED) at the same time as the
|
| -# writer was executing the UPDATE statement, then it could incorrectly
|
| -# rollback the statement-transaction belonging to the UPDATE statement.
|
| -# The UPDATE statement would still be reported as successful to the user,
|
| -# but it would have no effect on the database contents.
|
| -#
|
| -# Note that it has so far only proved possible to hit this race-condition
|
| -# when using an ATTACHed database. There doesn't seem to be any reason
|
| -# for this, other than that operating on an ATTACHed database means there
|
| -# are a few more mutex grabs and releases during the window of time open
|
| -# for the race-condition. Maybe this encourages the scheduler to context
|
| -# switch or something...
|
| -#
|
| -
|
| -file delete -force test.db test2.db
|
| -unset -nocomplain finished
|
| -
|
| -do_test thread005-2.1 {
|
| - sqlite3 db test.db
|
| - execsql { ATTACH 'test2.db' AS aux }
|
| - execsql {
|
| - CREATE TABLE aux.t1(a INTEGER PRIMARY KEY, b UNIQUE);
|
| - INSERT INTO t1 VALUES(1, 1);
|
| - INSERT INTO t1 VALUES(2, 2);
|
| - }
|
| - db close
|
| -} {}
|
| -
|
| -
|
| -set ThreadProgram {
|
| - proc execsql {zSql {db {}}} {
|
| - if {$db eq ""} {set db $::DB}
|
| -
|
| - set lRes [list]
|
| - set rc SQLITE_OK
|
| -
|
| - while {$rc=="SQLITE_OK" && $zSql ne ""} {
|
| - set STMT [sqlite3_prepare_v2 $db $zSql -1 zSql]
|
| - while {[set rc [sqlite3_step $STMT]] eq "SQLITE_ROW"} {
|
| - for {set i 0} {$i < [sqlite3_column_count $STMT]} {incr i} {
|
| - lappend lRes [sqlite3_column_text $STMT 0]
|
| - }
|
| - }
|
| - set rc [sqlite3_finalize $STMT]
|
| - }
|
| -
|
| - if {$rc != "SQLITE_OK"} { error "$rc [sqlite3_errmsg $db]" }
|
| - return $lRes
|
| - }
|
| -
|
| - if {$isWriter} {
|
| - set Sql {
|
| - BEGIN;
|
| - DELETE FROM t1 WHERE a = (SELECT max(a) FROM t1);
|
| - INSERT INTO t1 VALUES(NULL, NULL);
|
| - UPDATE t1 SET b = a WHERE a = (SELECT max(a) FROM t1);
|
| - SELECT count(*) FROM t1 WHERE b IS NULL;
|
| - COMMIT;
|
| - }
|
| - } else {
|
| - set Sql {
|
| - BEGIN;
|
| - SELECT count(*) FROM t1 WHERE b IS NULL;
|
| - COMMIT;
|
| - }
|
| - }
|
| -
|
| - set ::DB [sqlite3_open test.db]
|
| -
|
| - execsql { ATTACH 'test2.db' AS aux }
|
| -
|
| - set result "ok"
|
| - set finish [expr [clock_seconds]+5]
|
| - while {$result eq "ok" && [clock_seconds] < $finish} {
|
| - set rc [catch {execsql $Sql} msg]
|
| - if {$rc} {
|
| - if {[string match "SQLITE_LOCKED*" $msg]} {
|
| - catch { execsql ROLLBACK }
|
| - } else {
|
| - sqlite3_close $::DB
|
| - error $msg
|
| - }
|
| - } elseif {$msg ne "0"} {
|
| - set result "failed"
|
| - }
|
| - }
|
| -
|
| - sqlite3_close $::DB
|
| - set result
|
| -}
|
| -
|
| -# There is a race-condition in btree.c that means that if two threads
|
| -# attempt to open the same database at roughly the same time, and there
|
| -# does not already exist a shared-cache corresponding to that database,
|
| -# then two shared-caches can be created instead of one. Things still more
|
| -# or less work, but the two database connections do not use the same
|
| -# shared-cache.
|
| -#
|
| -# If the threads run by this test hit this race-condition, the tests
|
| -# fail (because SQLITE_BUSY may be unexpectedly returned instead of
|
| -# SQLITE_LOCKED). To prevent this from happening, open a couple of
|
| -# connections to test.db and test2.db now to make sure that there are
|
| -# already shared-caches in memory for all databases opened by the
|
| -# test threads.
|
| -#
|
| -sqlite3 db test.db
|
| -sqlite3 db test2.db
|
| -
|
| -puts "Running thread-tests for ~20 seconds"
|
| -thread_spawn finished(0) {set isWriter 0} $ThreadProgram
|
| -thread_spawn finished(1) {set isWriter 1} $ThreadProgram
|
| -if {![info exists finished(0)]} { vwait finished(0) }
|
| -if {![info exists finished(1)]} { vwait finished(1) }
|
| -
|
| -catch { db close }
|
| -catch { db2 close }
|
| -
|
| -do_test thread005-2.2 {
|
| - list $finished(0) $finished(1)
|
| -} {ok ok}
|
| -
|
| -do_test thread005-2.3 {
|
| - sqlite3 db test.db
|
| - execsql { ATTACH 'test2.db' AS aux }
|
| - execsql { SELECT count(*) FROM t1 WHERE b IS NULL }
|
| -} {0}
|
| -
|
| -sqlite3_enable_shared_cache $::enable_shared_cache
|
| -finish_test
|
|
|