# 2007 September 7
#
# 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: thread001.test,v 1.5 2008/07/12 14:52:20 drh Exp $

set testdir [file dirname $argv0]

source $testdir/tester.tcl
source $testdir/thread_common.tcl
if {[info commands sqlthread] eq ""} {
  return
}

set ::NTHREAD 10

# Run this test three times: 
# 
#    1) All threads use the same database handle.
#    2) All threads use their own database handles.
#    3) All threads use their own database handles, shared-cache is enabled.
#
foreach {tn same_db shared_cache} [list \
         1  1       0                   \
         2  0       0                   \
         3  0       1                   \
] {
  # Empty the database.
  #
  catchsql { DROP TABLE ab; }

  do_test thread001.$tn.0 {
    db close
    sqlite3_enable_shared_cache $shared_cache
    sqlite3_enable_shared_cache $shared_cache
  } $shared_cache
  sqlite3 db test.db

  set dbconfig ""
  if {$same_db} {
    set dbconfig [list set ::DB [sqlite3_connection_pointer db]]
  }

  # Set up a database and a schema. The database contains a single
  # table with two columns. The first column ("a") is an INTEGER PRIMARY 
  # KEY. The second contains the md5sum of all rows in the table with
  # a smaller value stored in column "a".
  #
  do_test thread001.$tn.1 {
    execsql {
      CREATE TABLE ab(a INTEGER PRIMARY KEY, b);
      CREATE INDEX ab_i ON ab(b);
      INSERT INTO ab SELECT NULL, md5sum(a, b) FROM ab;
      SELECT count(*) FROM ab;
    }
  } {1}
  do_test thread001.$tn.2 {
    execsql {
      SELECT 
        (SELECT md5sum(a, b) FROM ab WHERE a < (SELECT max(a) FROM ab)) ==
        (SELECT b FROM ab WHERE a = (SELECT max(a) FROM ab))
    }
  } {1}
  do_test thread001.$tn.3 {
    execsql { PRAGMA integrity_check }
  } {ok}
  
  set thread_program {
    set needToClose 0
    if {![info exists ::DB]} {
      set ::DB [sqlthread open test.db]
      set needToClose 1
    }
  
    for {set i 0} {$i < 100} {incr i} {
      # Test that the invariant is true.
      do_test t1 {
        execsql {
          SELECT 
            (SELECT md5sum(a, b) FROM ab WHERE a < (SELECT max(a) FROM ab)) ==
            (SELECT b FROM ab WHERE a = (SELECT max(a) FROM ab))
        }
      } {1}
  
      # Add another row to the database.
      execsql { INSERT INTO ab SELECT NULL, md5sum(a, b) FROM ab }
    }
  
    if {$needToClose} {
      sqlite3_close $::DB
    }
  
    list OK
  }
  
  # Kick off $::NTHREAD threads:
  #
  array unset finished
  for {set i 0} {$i < $::NTHREAD} {incr i} {
    thread_spawn finished($i) $dbconfig $thread_procs $thread_program
  }
  
  # Wait for all threads to finish,  then check they all returned "OK".
  #
  for {set i 0} {$i < $::NTHREAD} {incr i} {
    if {![info exists finished($i)]} {
      vwait finished($i)
    }
    do_test thread001.$tn.4.$i {
      set ::finished($i)
    } OK
  }
  
  # Check the database still looks Ok.
  #
  do_test thread001.$tn.5 {
    execsql { SELECT count(*) FROM ab; }
  } [expr {1 + $::NTHREAD*100}]
  do_test thread001.$tn.6 {
    execsql {
      SELECT 
        (SELECT md5sum(a, b) FROM ab WHERE a < (SELECT max(a) FROM ab)) ==
        (SELECT b FROM ab WHERE a = (SELECT max(a) FROM ab))
    }
  } {1}
  do_test thread001.$tn.7 {
    execsql { PRAGMA integrity_check }
  } {ok}
}

finish_test