c36dde3f45
Currently the layout of a struct is used to compute its size. This works fine in case of structs of fixed size. However this introduces forwards-compatibility problems in cases when the struct has multiple variants and the exact variant is specified by the value of some field (e.g. in the case of <switch> elements). Future revisions of protocols may introduce new layout variants, in which case the old code does not know the size of the struct variant and can't parse the incoming byte stream. Instead of relying on knowledge about the layout of data structures we should instead use the length field for length information. This way when old client libxcb communicates with newer server it can at least ignore unknown struct variants. |
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| doc | ||
| src | ||
| xcbgen | ||
| .gitignore | ||
| autogen.sh | ||
| configure.ac | ||
| COPYING | ||
| HACKING | ||
| INSTALL | ||
| Makefile.am | ||
| NEWS | ||
| README.md | ||
| TODO | ||
| xcb-proto.pc.in | ||
About xcb-proto
xcb-proto provides the XML-XCB protocol descriptions that libxcb uses to generate the majority of its code and API. We provide them separately from libxcb to allow reuse by other projects, such as additional language bindings, protocol dissectors, or documentation generators.
This separation between the XCB transport layer and the automatically-generated protocol layer also makes it far easier to write new extensions. With the Xlib infrastructure, client-side support for new extensions requires significant duplication of effort. With XCB and the XML-XCB protocol descriptions, client-side support for a new extension requires only an XML description of the extension, and not a single line of code.
Python libraries: xcb-proto also contains language-independent Python libraries that are used to parse an XML description and create objects used by Python code generators in individual language bindings. These libraries are installed into $(prefix)/lib/pythonX.X/site-packages. If this location is not on your system's Python path, scripts that import them will fail with import errors. In this case you must add the install location to your Python path by creating a file with a `.pth' extension in a directory that is on the Python path, and put the path to the install location in that file. For example, on my system there is a file named 'local.pth' in /usr/lib/python2.5/site-packages, which contains '/usr/local/lib/python2.5/site-packages'. Note that this is only necessary on machines where XCB is being built.
Please report any issues you find to the freedesktop.org bug tracker at:
https://gitlab.freedesktop.org/xorg/proto/xcbproto/issues
Discussion about XCB occurs on the XCB mailing list:
https://lists.freedesktop.org/mailman/listinfo/xcb
You can obtain the latest development versions of xcb-proto using GIT from the xcbproto code repository at:
https://gitlab.freedesktop.org/xorg/proto/xcbproto
For anonymous checkouts, use:
git clone https://gitlab.freedesktop.org/xorg/proto/xcbproto.git
For developers, use:
git clone git@gitlab.freedesktop.org:xorg/proto/xcbproto.git