test/malloc.test

# 2001 September 15
#
# 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.
#
#***********************************************************************
#
# This file attempts to check the behavior of the SQLite library in 
# an out-of-memory situation. When compiled with -DSQLITE_DEBUG=1, 
# the SQLite library accepts a special command (sqlite3_memdebug_fail N C)
# which causes the N-th malloc to fail.  This special feature is used
# to see what happens in the library if a malloc were to really fail
# due to an out-of-memory situation.
#
# $Id: malloc.test,v 1.74 2009/01/16 16:40:14 danielk1977 Exp $

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


# Only run these tests if memory debugging is turned on.
#
source $testdir/malloc_common.tcl
if {!$MEMDEBUG} {
   puts "Skipping malloc tests: not compiled with -DSQLITE_MEMDEBUG..."
   finish_test
   return
}

# Do a couple of memory dumps just to exercise the memory dump logic
# that that we can say that we have.
#
puts stderr "This is a test.  Ignore the error that follows:"
sqlite3_memdebug_dump $testdir
puts "Memory dump to file memdump.txt..."
sqlite3_memdebug_dump memdump.txt

ifcapable bloblit&&subquery {
  do_malloc_test 1 -tclprep {
    db close
  } -tclbody {
    if {[catch {sqlite3 db test.db}]} {
      error "out of memory"
    }
    sqlite3_extended_result_codes db 1
  } -sqlbody {
    DROP TABLE IF EXISTS t1;
    CREATE TABLE t1(
       a int, b float, c double, d text, e varchar(20),
       primary key(a,b,c)
    );
    CREATE INDEX i1 ON t1(a,b);
    INSERT INTO t1 VALUES(1,2.3,4.5,'hi',x'746865726500');
    INSERT INTO t1 VALUES(6,7.0,0.8,'hello','out yonder');
    SELECT * FROM t1;
    SELECT avg(b) FROM t1 GROUP BY a HAVING b>20.0;
    DELETE FROM t1 WHERE a IN (SELECT min(a) FROM t1);
    SELECT count(*), group_concat(e) FROM t1;
    SELECT b FROM t1 ORDER BY 1 COLLATE nocase;
  } 
}

# Ensure that no file descriptors were leaked.
do_test malloc-1.X {
  catch {db close}
  set sqlite_open_file_count
} {0}

ifcapable subquery {
  do_malloc_test 2 -sqlbody {
    CREATE TABLE t1(a int, b int default 'abc', c int default 1);
    CREATE INDEX i1 ON t1(a,b);
    INSERT INTO t1 VALUES(1,1,'99 abcdefghijklmnopqrstuvwxyz');
    INSERT INTO t1 VALUES(2,4,'98 abcdefghijklmnopqrstuvwxyz');
    INSERT INTO t1 VALUES(3,9,'97 abcdefghijklmnopqrstuvwxyz');
    INSERT INTO t1 VALUES(4,16,'96 abcdefghijklmnopqrstuvwxyz');
    INSERT INTO t1 VALUES(5,25,'95 abcdefghijklmnopqrstuvwxyz');
    INSERT INTO t1 VALUES(6,36,'94 abcdefghijklmnopqrstuvwxyz');
    SELECT 'stuff', count(*) as 'other stuff', max(a+10) FROM t1;
    UPDATE t1 SET b=b||b||b||b;
    UPDATE t1 SET b=a WHERE a in (10,12,22);
    INSERT INTO t1(c,b,a) VALUES(20,10,5);
    INSERT INTO t1 SELECT * FROM t1
        WHERE a IN (SELECT a FROM t1 WHERE a<10);
    DELETE FROM t1 WHERE a>=10;
    DROP INDEX i1;
    DELETE FROM t1;
  } 
}

# Ensure that no file descriptors were leaked.
do_test malloc-2.X {
  catch {db close}
  set sqlite_open_file_count
} {0}

do_malloc_test 3 -sqlbody {
  BEGIN TRANSACTION;
  CREATE TABLE t1(a int, b int, c int);
  CREATE INDEX i1 ON t1(a,b);
  INSERT INTO t1 VALUES(1,1,99);
  INSERT INTO t1 VALUES(2,4,98);
  INSERT INTO t1 VALUES(3,9,97);
  INSERT INTO t1 VALUES(4,16,96);
  INSERT INTO t1 VALUES(5,25,95);
  INSERT INTO t1 VALUES(6,36,94);
  INSERT INTO t1(c,b,a) VALUES(20,10,5);
  DELETE FROM t1 WHERE a>=10;
  DROP INDEX i1;
  DELETE FROM t1;
  ROLLBACK;
} 


# Ensure that no file descriptors were leaked.
do_test malloc-3.X {
  catch {db close}
  set sqlite_open_file_count
} {0}

ifcapable subquery {
  do_malloc_test 4 -sqlbody {
    BEGIN TRANSACTION;
    CREATE TABLE t1(a int, b int, c int);
    CREATE INDEX i1 ON t1(a,b);
    INSERT INTO t1 VALUES(1,1,99);
    INSERT INTO t1 VALUES(2,4,98);
    INSERT INTO t1 VALUES(3,9,97);
    INSERT INTO t1 VALUES(4,16,96);
    INSERT INTO t1 VALUES(5,25,95);
    INSERT INTO t1 VALUES(6,36,94);
    UPDATE t1 SET b=a WHERE a in (10,12,22);
    INSERT INTO t1 SELECT * FROM t1
       WHERE a IN (SELECT a FROM t1 WHERE a<10);
    DROP INDEX i1;
    DELETE FROM t1;
    COMMIT;
  } 
}

# Ensure that no file descriptors were leaked.
do_test malloc-4.X {
  catch {db close}
  set sqlite_open_file_count
} {0}

ifcapable trigger {
  do_malloc_test 5 -sqlbody {
    BEGIN TRANSACTION;
    CREATE TABLE t1(a,b);
    CREATE TABLE t2(x,y);
    CREATE TRIGGER r1 AFTER INSERT ON t1 WHEN new.a = 2 BEGIN
      INSERT INTO t2(x,y) VALUES(new.rowid,1);
      INSERT INTO t2(x,y) SELECT * FROM t2;
      INSERT INTO t2 SELECT * FROM t2;
      UPDATE t2 SET y=y+1 WHERE x=new.rowid;
      SELECT 123;
      DELETE FROM t2 WHERE x=new.rowid;
    END;
    INSERT INTO t1(a,b) VALUES(2,3);
    COMMIT;
  } 
}

# Ensure that no file descriptors were leaked.
do_test malloc-5.X {
  catch {db close}
  set sqlite_open_file_count
} {0}

ifcapable vacuum {
  do_malloc_test 6 -sqlprep {
    BEGIN TRANSACTION;
    CREATE TABLE t1(a);
    INSERT INTO t1 VALUES(1);
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    INSERT INTO t1 SELECT a*2 FROM t1;
    DELETE FROM t1 where rowid%5 = 0;
    COMMIT;
  } -sqlbody {
    VACUUM;
  } 
}

do_malloc_test 7 -sqlprep {
  CREATE TABLE t1(a, b);
  INSERT INTO t1 VALUES(1, 2);
  INSERT INTO t1 VALUES(3, 4);
  INSERT INTO t1 VALUES(5, 6);
  INSERT INTO t1 VALUES(7, randstr(1200,1200));
} -sqlbody {
  SELECT min(a) FROM t1 WHERE a<6 GROUP BY b;
  SELECT a FROM t1 WHERE a<6 ORDER BY a;
  SELECT b FROM t1 WHERE a>6;
}

# This block is designed to test that some malloc failures that may
# occur in vdbeapi.c. Specifically, if a malloc failure that occurs
# when converting UTF-16 text to integers and real numbers is handled
# correctly. 
#
# This is done by retrieving a string from the database engine and
# manipulating it using the sqlite3_column_*** APIs. This doesn't 
# actually return an error to the user when a malloc() fails.. That 
# could be viewed as a bug.
#
# These tests only run if UTF-16 support is compiled in.
#
ifcapable utf16 {
  set ::STMT {}
  do_malloc_test 8 -tclprep {
    set sql "SELECT '[string repeat abc 20]', '[string repeat def 20]', ?"
    set ::STMT [sqlite3_prepare db $sql -1 X]
    sqlite3_step $::STMT
    if { $::tcl_platform(byteOrder)=="littleEndian" } {
      set ::bomstr "\xFF\xFE"
    } else {
      set ::bomstr "\xFE\xFF"
    }
    append ::bomstr [encoding convertto unicode "123456789_123456789_12345678"]
  } -tclbody {
    sqlite3_column_text16 $::STMT 0
    sqlite3_column_int $::STMT 0
    sqlite3_column_text16 $::STMT 1
    sqlite3_column_double $::STMT 1
    set rc [sqlite3_reset $::STMT]
    if {$rc eq "SQLITE_NOMEM"} {error "out of memory"}
    sqlite3_bind_text16 $::STMT 1 $::bomstr 60
    #catch {sqlite3_finalize $::STMT}
    #if {[lindex [sqlite_malloc_stat] 2]<=0} {
    #  error "out of memory"
    #}
  } -cleanup {
    if {$::STMT!=""} {
      sqlite3_finalize $::STMT
      set ::STMT {}
    }
  }
}

# This block tests that malloc() failures that occur whilst commiting
# a multi-file transaction are handled correctly.
#
do_malloc_test 9 -sqlprep {
  ATTACH 'test2.db' as test2;
  CREATE TABLE abc1(a, b, c);
  CREATE TABLE test2.abc2(a, b, c);
} -sqlbody {
  BEGIN;
  INSERT INTO abc1 VALUES(1, 2, 3);
  INSERT INTO abc2 VALUES(1, 2, 3);
  COMMIT;
}

# This block tests malloc() failures that occur while opening a 
# connection to a database.
do_malloc_test 10 -tclprep {
  catch {db2 close}
  db close
  file delete -force test.db test.db-journal
  sqlite3 db test.db
  sqlite3_extended_result_codes db 1
  db eval {CREATE TABLE abc(a, b, c)}
} -tclbody {
  db close
  sqlite3 db2 test.db
  sqlite3_extended_result_codes db2 1
  db2 eval {SELECT * FROM sqlite_master}
  db2 close
}

# This block tests malloc() failures that occur within calls to
# sqlite3_create_function().
do_malloc_test 11 -tclbody {
  set rc [sqlite3_create_function db]
  if {[string match $rc SQLITE_OK]} {
    set rc [sqlite3_create_aggregate db]
  }
  if {[string match $rc SQLITE_NOMEM]} {
    error "out of memory"
  }
}

do_malloc_test 12 -tclbody {
  set sql16 [encoding convertto unicode "SELECT * FROM sqlite_master"]
  append sql16 "\00\00"
  set ::STMT [sqlite3_prepare16 db $sql16 -1 DUMMY]
  sqlite3_finalize $::STMT
}

# Test malloc errors when replaying two hot journals from a 2-file 
# transaction.
ifcapable crashtest&&attach {
  do_malloc_test 13 -tclprep {
    set rc [crashsql -delay 1 -file test2.db {
      ATTACH 'test2.db' as aux;
      PRAGMA cache_size = 10;
      BEGIN;
      CREATE TABLE aux.t2(a, b, c);
      CREATE TABLE t1(a, b, c);
      COMMIT;
    }]
    if {$rc!="1 {child process exited abnormally}"} {
      error "Wrong error message: $rc"
    }
  } -tclbody {
    db eval {ATTACH 'test2.db' as aux;}
    set rc [catch {db eval {
      SELECT * FROM t1; 
      SELECT * FROM t2;
    }} err]
    if {$rc && $err!="no such table: t1"} {
      error $err
    }
  }
}

if {$tcl_platform(platform)!="windows"} {
  do_malloc_test 14 -tclprep {
    catch {db close}
    sqlite3 db2 test2.db
    sqlite3_extended_result_codes db2 1
    db2 eval {
      PRAGMA synchronous = 0;
      CREATE TABLE t1(a, b);
      INSERT INTO t1 VALUES(1, 2);
      BEGIN;
      INSERT INTO t1 VALUES(3, 4);
    }
    copy_file test2.db test.db
    copy_file test2.db-journal test.db-journal
    db2 close
  } -tclbody {
    sqlite3 db test.db
    sqlite3_extended_result_codes db 1

    # If an out-of-memory occurs within a call to a VFS layer function during
    # hot-journal rollback, sqlite will report SQLITE_CORRUPT. See commit
    # [5668] for details.
    set rc [catch {db eval { SELECT * FROM t1 }} msg]
    if {$msg eq "database disk image is malformed"} { set msg "out of memory" }
    if {$rc} { error $msg }
    set msg
  }
}

proc string_compare {a b} {
  return [string compare $a $b]
}

# Test for malloc() failures in sqlite3_create_collation() and 
# sqlite3_create_collation16().
#
ifcapable utf16 {
  do_malloc_test 15 -start 4 -tclbody {
    db collate string_compare string_compare
    if {[catch {add_test_collate db 1 1 1} msg]} {
      if {$msg=="SQLITE_NOMEM"} {set msg "out of memory"}
      error $msg
    }
  
    db complete {SELECT "hello """||'world"' [microsoft], * FROM anicetable;}
    db complete {-- Useful comment}
  
    execsql {
      CREATE TABLE t1(a, b COLLATE string_compare);
      INSERT INTO t1 VALUES(10, 'string');
      INSERT INTO t1 VALUES(10, 'string2');
    }
  }
}

# Also test sqlite3_complete(). There are (currently) no malloc()
# calls in this function, but test anyway against future changes.
#
do_malloc_test 16 -tclbody {
  db complete {SELECT "hello """||'world"' [microsoft], * FROM anicetable;}
  db complete {-- Useful comment}
  db eval {
    SELECT * FROM sqlite_master;
  }
}

# Test handling of malloc() failures in sqlite3_open16().
#
ifcapable utf16 {
  do_malloc_test 17 -tclbody {
    set DB2 0
    set STMT 0
  
    # open database using sqlite3_open16()
    set filename [encoding convertto unicode test.db]
    append filename "\x00\x00"
    set DB2 [sqlite3_open16 $filename -unused]
    if {0==$DB2} {
      error "out of memory"
    }
    sqlite3_extended_result_codes $DB2 1
  
    # Prepare statement
    set rc [catch {sqlite3_prepare $DB2 {SELECT * FROM sqlite_master} -1 X} msg]
    if {[sqlite3_errcode $DB2] eq "SQLITE_IOERR+12"} {
      error "out of memory"
    }
    if {[regexp ".*automatic extension loading.*" [sqlite3_errmsg $DB2]]} {
      error "out of memory"
    }
    if {$rc} {
      error [string range $msg 4 end]
    }
    set STMT $msg
  
    # Finalize statement
    set rc [sqlite3_finalize $STMT]
    if {$rc!="SQLITE_OK"} {
      error [sqlite3_errmsg $DB2]
    }
    set STMT 0
  
    # Close database
    set rc [sqlite3_close $DB2]
    if {$rc!="SQLITE_OK"} {
      error [sqlite3_errmsg $DB2]
    }
    set DB2 0
  } -cleanup {
    if {$STMT!="0"} {
      sqlite3_finalize $STMT
    }
    if {$DB2!="0"} {
      set rc [sqlite3_close $DB2]
    }
  }
}

# Test handling of malloc() failures in sqlite3_errmsg16().
#
ifcapable utf16 {
  do_malloc_test 18 -tclprep {
    catch {
      db eval "SELECT [string repeat longcolumnname 10] FROM sqlite_master"
    }
  } -tclbody {
    set utf16 [sqlite3_errmsg16 [sqlite3_connection_pointer db]]
    binary scan $utf16 c* bytes
    if {[llength $bytes]==0} {
      error "out of memory"
    }
  }
}

# This test is aimed at coverage testing. Specificly, it is supposed to
# cause a malloc() only used when converting between the two utf-16 
# encodings to fail (i.e. little-endian->big-endian). It only actually 
# hits this malloc() on little-endian hosts.
#
set static_string "\x00h\x00e\x00l\x00l\x00o"
for {set l 0} {$l<10} {incr l} {
  append static_string $static_string
}
append static_string "\x00\x00"
do_malloc_test 19 -tclprep {
  execsql {
    PRAGMA encoding = "UTF16be";
    CREATE TABLE abc(a, b, c);
  }
} -tclbody {
  unset -nocomplain ::STMT
  set r [catch {
    set ::STMT [sqlite3_prepare db {SELECT ?} -1 DUMMY]
    sqlite3_bind_text16 -static $::STMT 1 $static_string 112
  } msg]
  if {$r} {error [string range $msg 4 end]}
  set msg
} -cleanup {
  if {[info exists ::STMT]} {
    sqlite3_finalize $::STMT
  }
}
unset static_string

# Make sure SQLITE_NOMEM is reported out on an ATTACH failure even
# when the malloc failure occurs within the nested parse.
#
ifcapable attach {
  do_malloc_test 20 -tclprep {
    db close
    file delete -force test2.db test2.db-journal
    sqlite3 db test2.db
    sqlite3_extended_result_codes db 1
    db eval {CREATE TABLE t1(x);}
    db close
  } -tclbody {
    if {[catch {sqlite3 db test.db}]} {
      error "out of memory"
    }
    sqlite3_extended_result_codes db 1
  } -sqlbody {
    ATTACH DATABASE 'test2.db' AS t2;
    SELECT * FROM t1;
    DETACH DATABASE t2;
  } 
}

# Test malloc failure whilst installing a foreign key.
#
ifcapable foreignkey {
  do_malloc_test 21 -sqlbody {
    CREATE TABLE abc(a, b, c, FOREIGN KEY(a) REFERENCES abc(b))
  } 
}

# Test malloc failure in an sqlite3_prepare_v2() call.
#
do_malloc_test 22 -tclbody {
  set ::STMT ""
  set r [catch {
    set ::STMT [
      sqlite3_prepare_v2 db "SELECT * FROM sqlite_master" -1 DUMMY
    ]
  } msg]
  if {$r} {error [string range $msg 4 end]}
} -cleanup {
  if {$::STMT ne ""} {
    sqlite3_finalize $::STMT
    set ::STMT ""
  }
}

ifcapable {pager_pragmas} {
  # This tests a special case - that an error that occurs while the pager
  # is trying to recover from error-state in exclusive-access mode works.
  #
  do_malloc_test 23 -tclprep {
    db eval {
      PRAGMA cache_size = 10;
      PRAGMA locking_mode = exclusive;
      BEGIN;
      CREATE TABLE abc(a, b, c);
      CREATE INDEX abc_i ON abc(a, b, c);
      INSERT INTO abc 
        VALUES(randstr(100,100), randstr(100,100), randstr(100,100));
      INSERT INTO abc 
        SELECT randstr(100,100), randstr(100,100), randstr(100,100) FROM abc;
      INSERT INTO abc 
        SELECT randstr(100,100), randstr(100,100), randstr(100,100) FROM abc;
      INSERT INTO abc 
        SELECT randstr(100,100), randstr(100,100), randstr(100,100) FROM abc;
      INSERT INTO abc 
        SELECT randstr(100,100), randstr(100,100), randstr(100,100) FROM abc;
      INSERT INTO abc 
        SELECT randstr(100,100), randstr(100,100), randstr(100,100) FROM abc;
      COMMIT;
    }
  
    # This puts the pager into error state.
    #
    db eval BEGIN
    db eval {UPDATE abc SET a = 0 WHERE oid%2}
    set ::sqlite_io_error_pending 10
    catch {db eval {ROLLBACK}} msg

  } -tclbody {
    # If an out-of-memory occurs within a call to a VFS layer function during
    # hot-journal rollback, sqlite will report SQLITE_CORRUPT. See commit
    # [5668] for details.
    set rc [catch {db eval { SELECT * FROM abc LIMIT 10 }} msg]
    if {$msg eq "database disk image is malformed"} { set msg "out of memory" }
    if {$rc} { error $msg }
    set msg
  } -cleanup {
    set e [db eval {PRAGMA integrity_check}]
    if {$e ne "ok"} {error $e}
  }
}

ifcapable compound {
  do_malloc_test 24 -sqlprep {
    CREATE TABLE t1(a, b, c)
  } -sqlbody {
    SELECT 1 FROM t1 UNION SELECT 2 FROM t1 ORDER BY 1
  }
}

ifcapable view&&trigger {
  do_malloc_test 25 -sqlprep {
    CREATE TABLE t1(a, b, c);
    CREATE VIEW v1 AS SELECT * FROM t1;
    CREATE TRIGGER v1t1 INSTEAD OF DELETE ON v1 BEGIN SELECT 1; END;
    CREATE TRIGGER v1t2 INSTEAD OF INSERT ON v1 BEGIN SELECT 1; END;
    CREATE TRIGGER v1t3 INSTEAD OF UPDATE ON v1 BEGIN SELECT 1; END;
  } -sqlbody {
    DELETE FROM v1 WHERE a = 1;
    INSERT INTO v1 VALUES(1, 2, 3);
    UPDATE v1 SET a = 1 WHERE b = 2;
  }
}

do_malloc_test 25 -sqlprep {
  CREATE TABLE abc(a, b, c);
  CREATE INDEX i1 ON abc(a, b);
  INSERT INTO abc VALUES(1, 2, 3);
  INSERT INTO abc VALUES(4, 5, 6);
} -tclbody {
  # For each UPDATE executed, the cursor used for the SELECT statement
  # must be "saved". Because the cursor is open on an index, this requires
  # a malloc() to allocate space to save the index key. This test case is
  # aimed at testing the response of the library to a failure in that
  # particular malloc() call.
  db eval {SELECT a FROM abc ORDER BY a} {
    db eval {UPDATE abc SET b = b - 1 WHERE a = $a}
  }
}

# This test is designed to test a specific juncture in the sqlite code.
# The database set up by -sqlprep script contains a single table B-Tree
# of height 2. In the -tclbody script, the existing database connection
# is closed and a new one opened and used to insert a new row into the
# table B-Tree. By using a new connection, the outcome of a malloc() 
# failure while seeking to the right-hand side of the B-Tree to insert 
# a new record can be tested.
#
do_malloc_test 26 -sqlprep {
  BEGIN;
  CREATE TABLE t1(a, b);
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  COMMIT;
} -tclbody {
  db close
  sqlite3 db test.db
  db eval { INSERT INTO t1 VALUES(1, randomblob(210)) }
}

# Test that no memory is leaked following a malloc() failure in
# sqlite3_initialize().
#
do_malloc_test 27 -tclprep {
  db close
  sqlite3_shutdown
} -tclbody {
  set rc [sqlite3_initialize]
  if {$rc == "SQLITE_NOMEM"} {
    error "out of memory"
  }
}

# Test that malloc failures that occur while processing INDEXED BY
# clauses are handled correctly.
do_malloc_test 28 -sqlprep {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a);
  CREATE VIEW v1 AS SELECT * FROM t1 INDEXED BY i1 WHERE a = 10;
} -sqlbody {
  SELECT * FROM t1 INDEXED BY i1 ORDER BY a;
  SELECT * FROM v1;
}

do_malloc_test 29 -sqlprep {
  CREATE TABLE t1(a TEXT, b TEXT);
} -sqlbody {
  INSERT INTO t1 VALUES(1, -234);
  INSERT INTO t1 SELECT * FROM t1 UNION ALL SELECT * FROM t1;
}

do_malloc_test 30 -tclprep {
  db eval {
    CREATE TABLE t1(x PRIMARY KEY);
    INSERT INTO t1 VALUES(randstr(500,500));
    INSERT INTO t1 VALUES(randstr(500,500));
    INSERT INTO t1 VALUES(randstr(500,500));
  }
  db close
  sqlite3 db test.db

  # The DELETE command in the following block moves the overflow pages that
  # are part of the primary key index to the free-list. But it does not
  # actually load the content of the pages. This leads to the peculiar
  # situation where cache entries exist, but are not populated with data.
  # They are populated next time they are requested by the b-tree layer.
  #
  db eval {
    BEGIN;
      DELETE FROM t1;
    ROLLBACK;
  }
} -sqlbody {
  -- This statement requires the 'no-content' pages loaded by the DELETE
  -- statement above. When requesting the pages, the content is loaded
  -- from the database file. The point of this test case is to test handling
  -- of malloc errors (including SQLITE_IOERR_NOMEM errors) when loading
  -- the content.
  SELECT * FROM t1 ORDER BY x;
}

# After committing a transaction in persistent-journal mode, if a journal
# size limit is configured SQLite may attempt to truncate the journal file.
# This test verifies the libraries response to a malloc() failure during
# this operation.
#
do_malloc_test 31 -sqlprep {
  PRAGMA journal_mode = persist;
  PRAGMA journal_size_limit = 1024;
  CREATE TABLE t1(a PRIMARY KEY, b);
} -sqlbody {
  INSERT INTO t1 VALUES(1, 2);
}

# When written, this test provoked an obscure change-counter bug.
# 
# If, when running in exclusive mode, a malloc() failure occurs
# after the database file change-counter has been written but
# before the transaction has been committed, then the transaction
# is automatically rolled back. However, internally the 
# Pager.changeCounterDone flag was being left set. This means
# that if the same connection attempts another transaction following
# the malloc failure and rollback, the change counter will not
# be updated. This could corrupt another processes cache.
#
do_malloc_test 32 -tclprep {
  # Build a small database containing an indexed table.
  #
  db eval {
    BEGIN;
    CREATE TABLE t1(a PRIMARY KEY, b);
    INSERT INTO t1 VALUES(1, 'one');
    INSERT INTO t1 VALUES(2, 'two');
    INSERT INTO t1 VALUES(3, 'three');
    COMMIT;
    PRAGMA locking_mode = exclusive;
  }

  # Open a second database connection. Load the table (but not index)
  # into the second connections pager cache.
  #
  sqlite3 db2 test.db
  db2 eval { SELECT b FROM t1 }

} -tclbody {
  # Running in exclusive mode, perform a database transaction that 
  # modifies both the database table and index. For iterations where
  # the malloc failure occurs after updating the change counter but
  # before committing the transaction, this should result in the
  # transaction being rolled back but the changeCounterDone flag
  # left set.
  #
  db eval { UPDATE t1 SET a = a + 3 }
} -cleanup {

  # Perform another transaction using the first connection. Unlock
  # the database after doing so. If this is one of the right iterations,
  # then this should result in the database contents being updated but
  # the change-counter left as it is.
  #
  db eval { 
    PRAGMA locking_mode = normal;
    UPDATE t1 SET a = a + 3;
  }

  # Now do an integrity check with the second connection. The second
  # connection still has the database table in its cache. If this is
  # one of the magic iterations and the change counter was not modified,
  # then it won't realize that the cached data is out of date. Since
  # the cached data won't match the up to date index data read from
  # the database file, the integrity check should fail.
  #
  set zRepeat "transient"
  if {$::iRepeat} {set zRepeat "persistent"}
  do_test malloc-32.$zRepeat.${::n}.integrity {
    execsql {PRAGMA integrity_check} db2
  } {ok}
  db2 close
}

# Ensure that no file descriptors were leaked.
do_test malloc-99.X {
  catch {db close}
  set sqlite_open_file_count
} {0}

puts open-file-count=$sqlite_open_file_count
finish_test