Is the SQLite3 gem known to have memory corruption?

Ruby
1

Running the following produces bizarre results (trimmed down from
an actual app):

#!/opt/local/bin/ruby

require ‘rubygems’
require_gem ‘sqlite3-ruby’

def each_batch(size=1)
until false
batch = []
(1…20).each {|i| batch << “x”}
yield batch
end
end

database = SQLite3::Database.new("/tmp/test.db")
counter = 0
each_batch {|batch|
database.transaction {
counter += batch.length
print “OK\n”
}
}

For a while it prints “OK”, but then eventually:

./test_bad_batch.rb:20: undefined method length' for 4085314:Fixnum (NoMethodError) from /opt/local/lib/ruby/gems/1.8/gems/sqlite3-ruby-1.1.0/ lib/sqlite3/database.rb:593:intransaction’
from ./test_bad_batch.rb:19
from ./test_bad_batch.rb:11:in each_batch' from ./test_bad_batch.rb:11:ineach_batch’
from ./test_bad_batch.rb:18

That is the ‘batch’ is getting yielded as random pointer instead
of the array generated inside each_batch!

I’ve tried narrowing this further (particularly getting rid of
SQLite usage), but this is the simplest case I can come up with so far.

I’m running on Mac OS X 10.4.4 with ruby 1.8.4 installed via
Darwin Ports (as well as rubygems installed from there and then
sqlite3 installed via that copy of gems).

% /opt/local/bin/ruby -v
ruby 1.8.4 (2005-12-24) [powerpc-darwin8.3.0]

% /opt/local/bin/gem list sqlite3-ruby

*** LOCAL GEMS ***

sqlite3-ruby (1.1.0)
SQLite3/Ruby is a module to allow Ruby scripts to interface with a
SQLite3 database.

I’ve tried both the system supplied sqlite (v3.1.3) and the latest
version (installed via Darwin Ports), 3.3.3.

Any info would be helpful!

-tim

2

Any info would be helpful!
See
http://rubyforge.org/tracker/index.php?func=detail&aid=2453&group_id=254&atid=1043
and the patch I submitted, which should fix the problem
http://rubyforge.org/tracker/index.php?func=detail&aid=2955&group_id=254&atid=1045

Regards,
Sylvain

3

Thanks; I’ve applied this patch in my /opt/local/lib/ruby/gems/1.8/
gems/sqlite3-ruby-1.1.0

It isn’t clear to me how to get the native code re-applied to the
gem. After patching sqlite3_api.i, I did:

% sudo ruby extconf.rb install sqlite3-ruby

but just reported there being nothing to do and re-running the
test case yielded the same problem.

I’m sorry if this is a basic question, but I’m new to patching
ruby itself. Any idea from the sqlite3 gem provider when this patch
might be included?

-tim

4

Thanks; this patch did in fact fix my issue. Of course, it took
me a while to figure out that I needed swig installed to get your
patch to do anything. Luckily I noticed the SWIG bug in the tracker :slight_smile:

-tim