[PATCH wayland-protocols v3] protocol: add compositor-debug.xml
external.mdevadoss at de.adit-jv.com
Fri Sep 22 09:17:49 UTC 2017
From: Pekka Paalanen <pq at iki.fi>
This is a new debugging extension for non-production environments. The
aim is to replace all build-time choosable debug prints in the
compositor with runtime subscribable debug streams.
Signed-off-by: Pekka Paalanen <pq at iki.fi>
Signed-off-by: Maniraj Devadoss <external.mdevadoss at de.adit-jv.com>
Makefile.am | 1 +
unstable/compositor-debug/README | 7 ++
.../compositor-debug-unstable-v1.xml | 128 +++++++++++++++++++++
3 files changed, 136 insertions(+)
create mode 100644 unstable/compositor-debug/README
create mode 100644 unstable/compositor-debug/compositor-debug-unstable-v1.xml
diff --git a/Makefile.am b/Makefile.am
index 5b5ae96..a0994d1 100644
@@ -15,6 +15,7 @@ unstable_protocols = \
+ unstable/compositor-debug/compositor-debug-unstable-v1.xml \
stable_protocols = \
diff --git a/unstable/compositor-debug/README b/unstable/compositor-debug/README
new file mode 100644
@@ -0,0 +1,7 @@
+Compositor Debug protocol
+Pekka Paalanen <pekka.paalanen at collabora.co.uk>
+Friedrich Eugen <efriedrich at de.adit-jv.com>
+Ucan Emre <eucan at de.adit-jv.com>
+Maniraj Devadoss <maniraj.devadoss at in.bosch.com>
diff --git a/unstable/compositor-debug/compositor-debug-unstable-v1.xml b/unstable/compositor-debug/compositor-debug-unstable-v1.xml
new file mode 100644
@@ -0,0 +1,128 @@
+<?xml version="1.0" encoding="UTF-8"?>
+ Copyright © 2017 Pekka Paalanen pq at iki.fi
+ Permission is hereby granted, free of charge, to any person obtaining a
+ copy of this software and associated documentation files (the "Software"),
+ to deal in the Software without restriction, including without limitation
+ the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ and/or sell copies of the Software, and to permit persons to whom the
+ Software is furnished to do so, subject to the following conditions:
+ The above copyright notice and this permission notice (including the next
+ paragraph) shall be included in all copies or substantial portions of the
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ DEALINGS IN THE SOFTWARE.
+ <interface name="zcompositor_debug_v1" version="1">
+ <description summary="compositor internal debugging">
+ This is a generic debugging interface for the compositor internals,the global
+ object advertized through wl_registry.
+ WARNING: This interface by design allows a denial-of-service attack. It
+ should not be offered in production, or proper authorization mechnisms
+ must be enforced.
+ The idea is for a client to provide a file descriptor that the server
+ uses for printing debug information. The server uses the file
+ descriptor in blocking writes mode, which exposes the denial-of-service
+ risk. The blocking mode is necessary to ensure all debug messages can
+ be easily printed in place. It also ensures message ordering if a
+ client subcribes to more than one debug stream.
+ The available debugging features depend on the server. There is no
+ explicit API for discovering the supported debug stream names. A server
+ should implement a debug stream named "list" where the server prints
+ the names and descriptions of all debug streams it supports to the
+ stream file descriptor.
+ A debug stream can be one-shot where the server prints the requested
+ information and then closes it, or continuous where server keeps on
+ printing until the client stops it. Or anything in between.
+ <request name="destroy" type="destructor">
+ <description summary="destroy factory object">
+ Destroys the factory object, but does not affect any other objects.
+ <request name="subscribe">
+ <description summary="subscribe to a debug stream">
+ Subscribe to a named debug stream. The server will start printing
+ to the given file descriptor.
+ If the named debug stream is a one-shot dump, the server will send
+ zcompositor_debug_v1.complete event once all requested data has
+ been printed. Otherwise, the server will continue streaming debug
+ prints until the subscription object is destroyed.
+ If the debug stream name is unknown to the server, the server will
+ immediately respond with zcompositor_debug_v1.failure event.
+ <arg name="name" type="string" allow-null="false"
+ summary="debug stream name"/>
+ <arg name="streamfd" type="fd" summary="write stream file descriptor"/>
+ <arg name="stream" type="new_id" interface="zcompositor_debug_stream_v1"
+ summary="created debug stream object"/>
+ <interface name="zcompositor_debug_stream_v1" version="1">
+ <description summary="A subscribed debug stream">
+ Represents one subscribed debug stream, created with
+ zcompositor_debug_v1.subscribe. When the object is created, it is associated
+ with a given file descriptor. The server will continue writing to the
+ file descriptor until the object is destroyed or the server sends an
+ event through the object.
+ <request name="destroy" type="destructor">
+ <description summary="close a debug stream">
+ Destroys the object, which causes the server to stop writing into
+ and closes the associated file descriptor if it was not closed
+ Use a wl_display.sync if the clients needs to guarantee the file
+ descriptor is closed before continuing.
+ <event name="complete">
+ <description summary="server completed the debug stream">
+ The server has successfully finished writing to and has closed the
+ associated file descriptor.
+ This event is delivered only for one-shot debug streams where the
+ server dumps some data and stop. This is never delivered for
+ continuous debbug streams because they by definition never complete.
+ <event name="failure">
+ <description summary="server cannot continue the debug stream">
+ The server has stopped writing to and has closed the
+ associated file descriptor. The data already written to the file
+ descriptor is correct, but it may be truncated.
+ This event may be delivered at any time and for any kind of debug
+ stream. It may be due to a failure in or shutdown of the server.
+ The message argument may provide a hint of the reason.
+ <arg name="message" type="string" allow-null="true"
+ summary="human readable reason"/>
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