Invalid files cause irrecoverable crashes in ROOTReader::openFile(...)

[veprbl]

• OS version: macOS
• Compiler version: 11.1.0
• PODIO version: 00-16-02
• Reproduced by:

#include <cstddef>

#include <podio/EventStore.h>
#include <podio/Frame.h>
#include <podio/ROOTFrameWriter.h>
#include <podio/ROOTReader.h>

#include <datamodel/EventInfoCollection.h>

int main() {
  {
    auto col = EventInfoCollection();

    col.create();

    podio::Frame frame;

    frame.put(std::move(col), "infos");

    podio::ROOTFrameWriter writer("frames.root");
    writer.writeFrame(frame, "events");
    writer.finish();
  }

  {
    auto reader = podio::ROOTReader();
    reader.openFile("frames.root");

    auto store = podio::EventStore();
    store.setReader(&reader);

    reader.closeFile();
  }

  return EXIT_SUCCESS;
}

• Input: link to input files if applicable
• Output:

 *** Break *** segmentation violation
[/usr/lib/system/libsystem_platform.dylib] _sigtramp (no debug info)
[<unknown binary>] (no debug info)
[/Users/veprbl/podio/prefix/lib/libpodioRootIO.so] podio::ROOTReader::openFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) /Users/veprbl/podio/src/ROOTReader.cc:140
[/Users/veprbl/podio/build/tests/roundtrip] main /Users/veprbl/podio/tests/roundtrip.cpp:27
[/usr/lib/system/libdyld.dylib] start (no debug info)
[<unknown binary>] (no debug info)

• Goal: We are looking to be able to be able to provide meaningful error messages. A typical case is to fail when a file with frames written by DD4hep 01-25+ is processed by the ROOTReader.

[tmadlener]

Thanks for reporting this. Given that the ROOTReader and the EventStore are deprecated now, we will probably not fix these. However, a similar issue exists in the new Frame based readers as well, where the only check that exists with a "nice" exception is whether the file exists.

This doesn't fix anything for you, but the python bindings deal with this slightly better as we have implemented some functionality there for detecting this:

from podio.reading import get_reader
reader = get_reader("<filename>")
# ...

podio/python/podio/reading.py

Lines 33 to 57 in 9cd0373

	def get_reader(filename):
	"""Get an appropriate reader for the passed file.
	Args:
	filename (str): The input file
	Returns:
	root_io.[Legacy]Reader, sio_io.[Legacy]Reader: an initialized reader that
	is able to process the input file.
	Raises:
	ValueError: If the file cannot be recognized, or if podio has not been
	built with the necessary backend I/O support
	"""
	if filename.endswith('.sio'):
	if _is_frame_sio_file(filename):
	return sio_io.Reader(filename)
	return sio_io.LegacyReader(filename)
	if filename.endswith('.root'):
	if _is_frame_root_file(filename):
	return root_io.Reader(filename)
	return root_io.LegacyReader(filename)
	raise ValueError('file must end on .root or .sio')

[tmadlener]

Closing this since the EventStore based Readers and Writers have been removed in #485