/* ** 2014 December 9 ** ** 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. ** ************************************************************************* ** ** lookaside1 */ /* ** The test in this file attempts to expose a specific race condition ** that is suspected to exist at time of writing. */ static char *lookaside1_thread_reader(int iTid, int iArg){ Error err = {0}; /* Error code and message */ Sqlite db = {0}; /* SQLite database connection */ opendb(&err, &db, "test.db", 0); while( !timetostop(&err) ){ sqlite3_stmt *pStmt = 0; int rc; sqlite3_prepare_v2(db.db, "SELECT 1 FROM t1", -1, &pStmt, 0); while( sqlite3_step(pStmt)==SQLITE_ROW ){ execsql(&err, &db, "SELECT length(x||y||z) FROM t2"); } rc = sqlite3_finalize(pStmt); if( err.rc==SQLITE_OK && rc!=SQLITE_OK ){ sqlite_error(&err, &db, "finalize"); } } closedb(&err, &db); print_and_free_err(&err); return sqlite3_mprintf("ok"); } static char *lookaside1_thread_writer(int iTid, int iArg){ Error err = {0}; /* Error code and message */ Sqlite db = {0}; /* SQLite database connection */ opendb(&err, &db, "test.db", 0); do{ sql_script(&err, &db, "BEGIN;" "UPDATE t3 SET i=i+1 WHERE x=1;" "ROLLBACK;" ); }while( !timetostop(&err) ); closedb(&err, &db); print_and_free_err(&err); return sqlite3_mprintf("ok"); } static void lookaside1(int nMs){ Error err = {0}; Sqlite db = {0}; Threadset threads = {0}; opendb(&err, &db, "test.db", 1); sql_script(&err, &db, "CREATE TABLE t1(x PRIMARY KEY) WITHOUT ROWID;" "WITH data(x,y) AS (" " SELECT 1, quote(randomblob(750)) UNION ALL " " SELECT x*2, y||y FROM data WHERE x<5) " "INSERT INTO t1 SELECT y FROM data;" "CREATE TABLE t3(x PRIMARY KEY,i) WITHOUT ROWID;" "INSERT INTO t3 VALUES(1, 1);" "CREATE TABLE t2(x,y,z);" "INSERT INTO t2 VALUES(randomblob(50), randomblob(50), randomblob(50));" ); closedb(&err, &db); setstoptime(&err, nMs); sqlite3_enable_shared_cache(1); launch_thread(&err, &threads, lookaside1_thread_reader, 0); launch_thread(&err, &threads, lookaside1_thread_reader, 0); launch_thread(&err, &threads, lookaside1_thread_reader, 0); launch_thread(&err, &threads, lookaside1_thread_reader, 0); launch_thread(&err, &threads, lookaside1_thread_reader, 0); launch_thread(&err, &threads, lookaside1_thread_writer, 0); join_all_threads(&err, &threads); sqlite3_enable_shared_cache(0); print_and_free_err(&err); }