gitlab.com/CoiaPrant/sqlite3@v1.19.1/testdata/tcl/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  if {[atomic_batch_write test.db]} {
    21    # This test uses two processes, one of which blocks until the other
    22    # creates a *-journal file. Which doesn't work if atomic writes are
    23    # available.
    24    finish_test
    25    return
    26  }
    27  
    28  do_not_use_codec
    29  
    30  # Initialize the test.db database so that it is non-empty
    31  #
    32  do_test lock4-1.1 {
    33    db eval {
    34       PRAGMA auto_vacuum=OFF;
    35       CREATE TABLE t1(x);
    36    }
    37    forcedelete test2.db test2.db-journal
    38    sqlite3 db2 test2.db
    39    db2 eval {
    40       PRAGMA auto_vacuum=OFF;
    41       CREATE TABLE t2(x)
    42    }
    43    db2 close
    44    list [file size test.db] [file size test2.db]
    45  } {2048 2048}
    46  
    47  # Create a script to drive a separate process that will
    48  #
    49  #     1.  Create a second database test2.db
    50  #     2.  Get an exclusive lock on test2.db
    51  #     3.  Add an entry to test.db in table t1, waiting as necessary.
    52  #     4.  Commit the change to test2.db.
    53  #
    54  # Meanwhile, this process will:
    55  # 
    56  #     A.  Get an exclusive lock on test.db
    57  #     B.  Attempt to read from test2.db but get an SQLITE_BUSY error.
    58  #     C.  Commit the changes to test.db thus alloing the other process
    59  #         to continue.
    60  #
    61  do_test lock4-1.2 {
    62   
    63    # Create a script for the second process to run.
    64    #
    65    set out [open test2-script.tcl w]
    66    puts $out "sqlite3_test_control_pending_byte [set sqlite_pending_byte]"
    67    puts $out {
    68       sqlite3 db2 test2.db
    69       db2 eval {
    70          BEGIN;
    71          INSERT INTO t2 VALUES(2);
    72       }
    73       sqlite3 db test.db
    74       db timeout 1000000
    75       db eval {
    76          INSERT INTO t1 VALUES(2);
    77       }
    78       db close
    79       db2 eval COMMIT
    80       exit
    81    }
    82    close $out
    83  
    84    # Begin a transaction on test.db.
    85    db eval {
    86       BEGIN EXCLUSIVE;
    87       INSERT INTO t1 VALUES(1);
    88    }
    89  
    90    # Kick off the second process.
    91    exec [info nameofexec] ./test2-script.tcl &
    92  
    93    # Wait until the second process has started its transaction on test2.db.
    94    while {![file exists test2.db-journal]} {
    95      after 10
    96    }
    97  
    98    # Try to write to test2.db. We are locked out.
    99    sqlite3 db2 test2.db
   100    catchsql {
   101      INSERT INTO t2 VALUES(1)
   102    } db2
   103  } {1 {database is locked}}
   104  do_test lock4-1.3 {
   105    db eval {
   106       COMMIT;
   107    }
   108    while {[file exists test2.db-journal]} {
   109      after 10
   110    }
   111    # The other process has committed its transaction on test2.db by 
   112    # deleting the journal file. But it might retain the lock for a 
   113    # fraction longer 
   114    #
   115    after 25
   116    db2 eval {
   117       SELECT * FROM t2
   118    }
   119  } {2}
   120  
   121      
   122  do_test lock4-999.1 {
   123    rename db2 {}
   124  } {}
   125  
   126  finish_test