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Overview
Comment:Fix a problem in shared-cache mode where a COMMIT statement might cause a busy-handler belonging to a shared-cache connection other than the current writer to be invoked.
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SHA1: e0c889d66ccf4af12cc77ac38c1e6477da63ac72
User & Date: dan 2012-10-05 19:43:02
Context
2012-10-06
03:48
Changes for WinRT compatibility. Also, allow version resource compilation and embedding to be disabled at compile-time. check-in: 4b0facc1 user: mistachkin tags: trunk
2012-10-05
19:43
Fix a problem in shared-cache mode where a COMMIT statement might cause a busy-handler belonging to a shared-cache connection other than the current writer to be invoked. check-in: e0c889d6 user: dan tags: trunk
17:44
Merge the shared-cache related fixes from the shared-cache-fix branch to the trunk. check-in: 698ec776 user: dan tags: trunk
Changes
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Changes to src/vdbeaux.c.

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  ** file is required for an atomic commit.
  */ 
  for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
    Btree *pBt = db->aDb[i].pBt;
    if( sqlite3BtreeIsInTrans(pBt) ){
      needXcommit = 1;
      if( i!=1 ) nTrans++;

      rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));

    }
  }
  if( rc!=SQLITE_OK ){
    return rc;
  }

  /* If there are any write-transactions at all, invoke the commit hook */







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  ** file is required for an atomic commit.
  */ 
  for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
    Btree *pBt = db->aDb[i].pBt;
    if( sqlite3BtreeIsInTrans(pBt) ){
      needXcommit = 1;
      if( i!=1 ) nTrans++;
      sqlite3BtreeEnter(pBt);
      rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));
      sqlite3BtreeLeave(pBt);
    }
  }
  if( rc!=SQLITE_OK ){
    return rc;
  }

  /* If there are any write-transactions at all, invoke the commit hook */

Changes to test/shared9.test.

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# The tests in this file are intended to show if two connections attach
# to the same shared cache using different database names, views and
# virtual tables may still be accessed.
#

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

set testprefix shared9

ifcapable !view||!trigger {
  finish_test
  return
}

................................................................................
  set ::invoked_mycollate_db1 0
  db2 eval {
    INSERT INTO t1 VALUES('two');
  }
  db2 close
  set ::invoked_mycollate_db1
} {0}



































































sqlite3_enable_shared_cache $::enable_shared_cache
finish_test








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# The tests in this file are intended to show if two connections attach
# to the same shared cache using different database names, views and
# virtual tables may still be accessed.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/lock_common.tcl
set testprefix shared9

ifcapable !view||!trigger {
  finish_test
  return
}

................................................................................
  set ::invoked_mycollate_db1 0
  db2 eval {
    INSERT INTO t1 VALUES('two');
  }
  db2 close
  set ::invoked_mycollate_db1
} {0}

#-------------------------------------------------------------------------
# This test verifies that a bug causing a busy-handler belonging to one
# shared-cache connection to be executed as a result of an sqlite3_step()
# on another has been fixed.
#
forcedelete test.db test.db2
sqlite3 db1 test.db
sqlite3 db2 test.db

proc busyhandler {handle args} {
  set ::busyhandler_invoked_for $handle
  return 1
}
db1 busy [list busyhandler db1]
db2 busy [list busyhandler db2]

do_test 3.1 {
  db1 eval {
    BEGIN; 
      CREATE TABLE t1(a, b);
      CREATE TABLE t2(a, b);
      INSERT INTO t1 VALUES(1, 2);
      INSERT INTO t2 VALUES(1, 2);
  }
  # Keep this next COMMIT as a separate statement. This ensures that COMMIT
  # has already been compiled and loaded into the tcl interface statement 
  # cache when it is attempted below.
  db1 eval COMMIT
  db1 eval {
    BEGIN;
      INSERT INTO t1 VALUES(3, 4);
  }
} {}

do_test 3.3 {
  set ::tf [launch_testfixture]
  testfixture $::tf {
    sqlite3 db test.db
    db eval {
      BEGIN;
        SELECT * FROM t1;
    }
  }
} {1 2}

do_test 3.2 {
  db2 eval { SELECT * FROM t2 }
} {1 2}

do_test 3.3 {
  list [catch { db1 eval COMMIT } msg] $msg
} {1 {database is locked}}

# At one point the following would fail, showing that the busy-handler
# belonging to [db2] was invoked instead.
do_test 3.4 {
  set ::busyhandler_invoked_for
} {db1}
do_test 3.5 {
  close $::tf
  db1 eval COMMIT
} {}
  
db1 close
db2 close

sqlite3_enable_shared_cache $::enable_shared_cache
finish_test