modernc.org/cc@v1.0.1/v2/testdata/_sqlite/test/lock4.test (about)

     1  # 2007 April 6
     2  #
     3  # The author disclaims copyright to this source code.  In place of
     4  # a legal notice, here is a blessing:
     5  #
     6  #    May you do good and not evil.
     7  #    May you find forgiveness for yourself and forgive others.
     8  #    May you share freely, never taking more than you give.
     9  #
    10  #***********************************************************************
    11  # This file implements regression tests for SQLite library.  The
    12  # focus of this script is database locks.
    13  #
    14  # $Id: lock4.test,v 1.10 2009/05/06 00:52:41 drh Exp $
    15  
    16  
    17  set testdir [file dirname $argv0]
    18  source $testdir/tester.tcl
    19  
    20  do_not_use_codec
    21  
    22  # Initialize the test.db database so that it is non-empty
    23  #
    24  do_test lock4-1.1 {
    25    db eval {
    26       PRAGMA auto_vacuum=OFF;
    27       CREATE TABLE t1(x);
    28    }
    29    forcedelete test2.db test2.db-journal
    30    sqlite3 db2 test2.db
    31    db2 eval {
    32       PRAGMA auto_vacuum=OFF;
    33       CREATE TABLE t2(x)
    34    }
    35    db2 close
    36    list [file size test.db] [file size test2.db]
    37  } {2048 2048}
    38  
    39  # Create a script to drive a separate process that will
    40  #
    41  #     1.  Create a second database test2.db
    42  #     2.  Get an exclusive lock on test2.db
    43  #     3.  Add an entry to test.db in table t1, waiting as necessary.
    44  #     4.  Commit the change to test2.db.
    45  #
    46  # Meanwhile, this process will:
    47  # 
    48  #     A.  Get an exclusive lock on test.db
    49  #     B.  Attempt to read from test2.db but get an SQLITE_BUSY error.
    50  #     C.  Commit the changes to test.db thus alloing the other process
    51  #         to continue.
    52  #
    53  do_test lock4-1.2 {
    54   
    55    # Create a script for the second process to run.
    56    #
    57    set out [open test2-script.tcl w]
    58    puts $out "sqlite3_test_control_pending_byte [set sqlite_pending_byte]"
    59    puts $out {
    60       sqlite3 db2 test2.db
    61       db2 eval {
    62          BEGIN;
    63          INSERT INTO t2 VALUES(2);
    64       }
    65       sqlite3 db test.db
    66       db timeout 1000000
    67       db eval {
    68          INSERT INTO t1 VALUES(2);
    69       }
    70       db close
    71       db2 eval COMMIT
    72       exit
    73    }
    74    close $out
    75  
    76    # Begin a transaction on test.db.
    77    db eval {
    78       BEGIN EXCLUSIVE;
    79       INSERT INTO t1 VALUES(1);
    80    }
    81  
    82    # Kick off the second process.
    83    exec [info nameofexec] ./test2-script.tcl &
    84  
    85    # Wait until the second process has started its transaction on test2.db.
    86    while {![file exists test2.db-journal]} {
    87      after 10
    88    }
    89  
    90    # Try to write to test2.db. We are locked out.
    91    sqlite3 db2 test2.db
    92    catchsql {
    93      INSERT INTO t2 VALUES(1)
    94    } db2
    95  } {1 {database is locked}}
    96  do_test lock4-1.3 {
    97    db eval {
    98       COMMIT;
    99    }
   100    while {[file exists test2.db-journal]} {
   101      after 10
   102    }
   103    # The other process has committed its transaction on test2.db by 
   104    # deleting the journal file. But it might retain the lock for a 
   105    # fraction longer 
   106    #
   107    after 25
   108    db2 eval {
   109       SELECT * FROM t2
   110    }
   111  } {2}
   112  
   113      
   114  do_test lock4-999.1 {
   115    rename db2 {}
   116  } {}
   117  
   118  finish_test