fd49b0140e
* Use a single Message type `v1/message.go` and `message.go` are the same now, and they embed `protobuf.ChatMessage` * Use `SendChatMessage` for sending chat messages, this is basically the old `Send` but a bit more flexible so we can send different message types (stickers,commands), and not just text. * Remove dedup from services/shhext. Because now we process in status-protocol, dedup makes less sense, as those messages are going to be processed anyway, so removing for now, we can re-evaluate if bringing it to status-go or not. * Change the various retrieveX method to a single one: `RetrieveAll` will be processing those messages that it can process (Currently only `Message`), and return the rest in `RawMessages` (still transit). The format for the response is: `Chats`: -> The chats updated by receiving the message `Messages`: -> The messages retrieved (already matched to a chat) `Contacts`: -> The contacts updated by the messages `RawMessages` -> Anything else that can't be parsed, eventually as we move everything to status-protocol-go this will go away.
Yet another USB library for Go
The usb package is a cross platform, fully self-contained library for accessing and communicating with USB devices either via HID or low level interrupts. The goal of the library was to create a simple way to find-, attach to- and read/write form USB devices.
There are multiple already existing USB libraries:
- The original
gousbpackage created by @kylelemons and nowadays maintained by @google is a CGO wrapper aroundlibusb. It is the most advanced USB library for Go out there.- Unfortunately,
gousbrequires thelibusbC library to be installed both during build as well as during runtime on the host operating system. This breaks binary portability and also adds unnecessary hurdles on Windows. - Furthermore, whilst HID devices are supported by
libusb, the OS on Macos and Windows explicitly takes over these devices, so only native system calls can be used on recent versions (i.e. you cannot uselibusbfor HID).
- Unfortunately,
- There is a fork of
gousbcreated by @karalabe that statically linkedlibusbduring build, but with the lack of HID access, that work was abandoned. - For HID-only devices, a previous self-contained package was created at
github.com/karalabe/hid, which worked well for hardware wallet uses cases ingo-ethereum. It's a simple package that does it's thing well.- Unfortunately,
hidis not capable of talking to generic USB devices. When multiple different devices are needed, eventually some will not support the HID spec (e.g. WebUSB). Pulling in bothhidandgousbwill break down due to both depending internally on different versions oflibusbon Linux.
- Unfortunately,
This usb package is a proper integration of hidapi and libusb so that communication with HID devices is done via system calls, whereas communication with lower level USB devices is done via interrupts. All this detail is hidden away behind a tiny interface.
The package supports Linux, macOS, Windows and FreeBSD. Exclude constraints are also specified for Android and iOS to allow smoother vendoring into cross platform projects.
Cross-compiling
Using go get, the embedded C library is compiled into the binary format of your host OS. Cross compiling to a different platform or architecture entails disabling CGO by default in Go, causing device enumeration hid.Enumerate() to yield no results.
To cross compile a functional version of this library, you'll need to enable CGO during cross compilation via CGO_ENABLED=1 and you'll need to install and set a cross compilation enabled C toolkit via CC=your-cross-gcc.
Acknowledgements
Although the usb package is an implementation from scratch, HID support was heavily inspired by the existing go.hid library, which seems abandoned since 2015; is incompatible with Go 1.6+; and has various external dependencies.
Wide character support in the HID support is done via the gowchar library, unmaintained since 2013; non buildable with a modern Go release and failing go vet checks. As such, gowchar was also vendored in inline.
Error handling for the libusb integration originates from the gousb library.
License
This USB library is licensed under the GNU Lesser General Public License v3.0 (dictated by libusb).
If you are only interested in Human Interface devices, a less restrictive package can be found at github.com/karalabe/hid.