SQLite

**
*************************************************************************
**
** This file contains the implementation of some Tcl commands used to
** test that sqlite3 database handles may be concurrently accessed by 
** multiple threads. Right now this only works on unix.
**
** $Id: test_thread.c,v 1.14 2009/03/24 18:42:16 drh Exp $
*/

#include "sqliteInt.h"
#include <tcl.h>

#if SQLITE_THREADSAFE

  int rc;
  SqlThread *p = (SqlThread *)pSqlThread;
  extern int Sqlitetest_mutex_Init(Tcl_Interp*);

  interp = Tcl_CreateInterp();
  Tcl_CreateObjCommand(interp, "clock_seconds", clock_seconds_proc, 0, 0);
  Tcl_CreateObjCommand(interp, "sqlthread", sqlthread_proc, pSqlThread, 0);
#if defined(SQLITE_OS_UNIX) && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
  Tcl_CreateObjCommand(interp, "sqlite3_blocking_step", blocking_step_proc,0,0);
  Tcl_CreateObjCommand(interp, 
      "sqlite3_blocking_prepare_v2", blocking_prepare_v2_proc, (void *)1, 0);
  Tcl_CreateObjCommand(interp, 
      "sqlite3_nonblocking_prepare_v2", blocking_prepare_v2_proc, 0, 0);
#endif
  Sqlitetest1_Init(interp);

** The source code for the C functions sqlite3_blocking_step(),
** blocking_step_notify() and the structure UnlockNotification is
** automatically extracted from this file and used as part of the
** documentation for the sqlite3_unlock_notify() API function. This
** should be considered if these functions are to be extended (i.e. to 
** support windows) in the future.
*/ 
#if defined(SQLITE_OS_UNIX) && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)

/* BEGIN_SQLITE_BLOCKING_STEP */
/* This example uses the pthreads API */
#include <pthread.h>

/*
** A pointer to an instance of this structure is passed as the user-context

/*
** Register commands with the TCL interpreter.
*/
int SqlitetestThread_Init(Tcl_Interp *interp){
  Tcl_CreateObjCommand(interp, "sqlthread", sqlthread_proc, 0, 0);
  Tcl_CreateObjCommand(interp, "clock_seconds", clock_seconds_proc, 0, 0);
#if defined(SQLITE_OS_UNIX) && defined(SQLITE_ENABLE_UNLOCK_NOTIFY)
  Tcl_CreateObjCommand(interp, "sqlite3_blocking_step", blocking_step_proc,0,0);
  Tcl_CreateObjCommand(interp, 
      "sqlite3_blocking_prepare_v2", blocking_prepare_v2_proc, (void *)1, 0);
  Tcl_CreateObjCommand(interp, 
      "sqlite3_nonblocking_prepare_v2", blocking_prepare_v2_proc, 0, 0);
#endif
  return TCL_OK;
}
#else
int SqlitetestThread_Init(Tcl_Interp *interp){
  return TCL_OK;
}
#endif

# 2009 March 04
#
# 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.
#
#***********************************************************************
#
# $Id: notify2.test,v 1.4 2009/03/24 18:42:16 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# The tests in this file test the sqlite3_blocking_step() function in
# test_thread.c. sqlite3_blocking_step() is not an SQLite API function,
# it is just a demonstration of how the sqlite3_unlock_notify() function

}
db close
set ::enable_shared_cache [sqlite3_enable_shared_cache 1]
source $testdir/thread_common.tcl

# Number of threads to run simultaneously.
#
set nThread 6
set nSecond 5

# The Tcl script executed by each of the $nThread threads used by this test.
#
set ThreadProgram {

  # Proc used by threads to execute SQL.

           + (SELECT max(a) FROM t2)
           + (SELECT max(a) FROM t3)
    }]
    db close
  } {}
}

# The following tests checks to make sure sqlite3_blocking_step() is
# faster than sqlite3_step().  blocking_step() is always faster on
# multi-core and is usually faster on single-core.  But sometimes, by
# chance, step() will be faster on a single core, in which case the
# following test will fail.
#
puts [array get anWrite]
do_test notify2-3 {
  expr {$anWrite(sqlite3_blocking_step) > $anWrite(sqlite3_step)}
} {1}

sqlite3_enable_shared_cache $::enable_shared_cache
finish_test