mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-27 12:11:13 +00:00
107 lines
4.6 KiB
Text
107 lines
4.6 KiB
Text
Moving around plug-ins between source modules
|
|
---------------------------------------------
|
|
|
|
Last updated: 2005-11-18
|
|
|
|
How to get your plug-in out of -bad and into -good or -ugly
|
|
-----------------------------------------------------------
|
|
|
|
Since GStreamer 0.9.x, we have four plugin modules: -base, -good, -ugly,
|
|
and -bad. Plug-ins are by default added to -bad. They can only move
|
|
to -good or -ugly if a number of conditions are met:
|
|
|
|
- People involved:
|
|
- There should be a person who is actively going to maintain this element;
|
|
presumably this is the person writing the plug-in in the first place
|
|
- There should be a GStreamer hacker who is willing to sponsor the element;
|
|
this would be someone who is going to help out getting all the conditions
|
|
met
|
|
- There should be a core developer who verifies the merge
|
|
|
|
The three roles can be filled by two people, but not just one.
|
|
|
|
- The plug-in's code:
|
|
- should descend from an applicable base class if possible
|
|
- make use of GST_BOILERPLATE macros
|
|
- conform to the GStreamer coding style
|
|
- use a custom debug category
|
|
- use GST_(DEBUG/*)_OBJECT
|
|
- use dashes in object property names to separate words
|
|
- use correct value, name, nick for enums
|
|
- use underscores in macros/function names/structs
|
|
e.g.: GST_BASE_SINK, GstBaseSink, gst_base_sink_
|
|
|
|
- The plug-in's build:
|
|
- should be correctly integrated with configure.ac
|
|
- files implementing elements should be named according to their class name,
|
|
e.g GstBaseSink -> gstbasesink.c
|
|
- should list libs and cflags in stack order, with lowest in the stack first
|
|
(so one can link against highest in the stack somewhere else without
|
|
picking up everything from the somewhere else)
|
|
e.g. $(GST_PLUGINS_BASE_CFLAGS) \
|
|
$(GST_BASE_CFLAGS) \
|
|
$(GST_CFLAGS) $(CAIRO_CFLAGS)
|
|
|
|
- The compiled plug-in:
|
|
- should show up correct in gst-inspect output; no warnings, no unknown
|
|
types, ...
|
|
|
|
- The plug-in should be put in the correct location inside the module:
|
|
sys/: plug-ins that include system headers/link to system libraries;
|
|
usually platform-dependent as well
|
|
name after whatever system "thing" they use (oss, v4l, ...)
|
|
gst/: plug-ins with no external dependencies, only GLib/GStreamer/liboil
|
|
ext/: plug-ins with external dependencies
|
|
|
|
- The plug-in is documented:
|
|
- the compiled-in descriptions should be correct
|
|
- every element in the plug-in should have gtk-doc documentation:
|
|
- longer description of element
|
|
- why you would use this element
|
|
- example launch line OR example source code
|
|
(for example, see
|
|
http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-base-plugins/html/gst-plugins-base-plugins-audiotestsrc.html
|
|
for the first and
|
|
http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-good-plugins/html/gst-plugins-good-plugins-level.html
|
|
for the second)
|
|
- if the element has custom messages, they should be documented
|
|
- signals and properties should be documented
|
|
|
|
- The plug-in should come with tests:
|
|
- preferably, a unit test should be written, testing things like:
|
|
- setup and teardown
|
|
- push in buffers in all supported formats and verify they are handled
|
|
properly
|
|
- push in buffers that trigger error cases, and verify errors are
|
|
correctly thrown
|
|
|
|
for example, see gst-plugins-base/check/elements/audioconvert
|
|
|
|
The unit test should be put in check/elements/(nameofelement)
|
|
and be added to check_PROGRAMS and Makefile.am
|
|
|
|
- if a unit test is not appropriate (for example, device elements),
|
|
a test application should be written that can be run manually
|
|
|
|
- The tests should be leak-free, tested with valgrind
|
|
- the unit tests in check/ dirs are valgrinded by default
|
|
- the manual tests should have a valgrind target
|
|
- leaks in the supporting library (and verified to be in the supporting
|
|
library !) can be added to suppressions files
|
|
|
|
- The elements should not segfault under any circumstance. This includes:
|
|
- wrong pipelines
|
|
- bad data
|
|
|
|
- The plugins need to be marked correctly for translations.
|
|
- All error conditions should be correctly handled using GST_ELEMENT_ERROR
|
|
and following practice outlined in
|
|
http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstGError.html
|
|
|
|
- Decision should be made if it should go into good (LGPL license,
|
|
LGPL dependencies, no patent issues) or ugly
|
|
|
|
- plugin documentation needs to be added:
|
|
- see gstreamer/docs/README; section on adding plugins and elements
|
|
- "make update" in docs/plugins and commit the new file
|
|
- edit -docs.sgml and add an include for the file
|