Readme for MTP tools

The project contains an Wireshark plugin to deal with PTP / MTP / PTP-IP / Fuji PTP over IP in various flavors. One of the goals was to to create an easy to extend Wireshark dissector for PTP.

The toolchain implements:

• extract the descriptions of PTP types and constants to JSON from other sources: ptp_descriptions
• generate code for dealing with PTP data based on JSON API descriptions code_generation
• an example of such generated code: wireshark, an wireshark dissector lua plugin that extracts much more of PTP data that the original C-based dissector plugin

The code-generation approach is influenced by

• go-mtpfs , esp. munge.py

• NikonHacker PTP-over-usb support

Licensing:

I hope I can explain it as simple as possible. And: IANAL. In my understanding, extracting constants from some source code produces 'derivate work'. So using one of the scripts in ptp_descriptions creates a JSON file that has the same license as the original source code. This gives the following matrix:

• my code is under the BSD license
• the MTP constants in mtp_description.json are based on wpdmtp is under the BSD license
• the vendor specific ptp_*.json descriptions are based libgphoto ptp.h and under the LGPL license
• any code using wireshark APIs is under the GPL license. See https://ask.wireshark.org/questions/12371/wireshark-plugin-and-gpl-license

This means:

• using the code-generator with your own templates to create some source based on descriptions in ptp-bsd-license will generate BSD-licensed code.
• using the code-generator with your own templates to create some source based on descriptions in ptp-lgpl-license will generate LGPL-licensed code.
• using the code-generator to generate an Wireshark dissector will build GPL code, regardless of the descriptions used.