android_development/tools/winscope

Tool for visualizing window manager traces

Developing WinScope

When the trace is enabled, Window Manager and Surface Flinger capture and save current state to a file at each point of interest. frameworks/base/core/proto/android/server/windowmanagertrace.proto and frameworks/native/services/surfaceflinger/layerproto/layerstrace.proto contain the proto definitions for their internal states.

Checking out code and setting up environment

• Download Android source
• Navigate to development/tools/winscope
• Run npm install

Build & test & deploy changes

• Navigate to development/tools/winscope
• Run npm run to get the list of available commands

Update IntDefMapping

• Build framework-minus-apex-intdefs module and a preprocessor will generate the latest IntDefMapping. From the ANDROID_ROOT run:

. build/envsetup.sh
m framework-minus-apex-intdefs

• Copy the generated intDefMapping.json files to the prebuilts repo.

python3 -c 'import sys,json,collections; print(json.dumps(collections.OrderedDict(sorted(collections.ChainMap(*map(lambda x:json.load(open(x)), sys.argv[1:])).items())), indent=2))' $(find out/soong/.intermediates/frameworks/base -iname intDefMapping.json) > ./prebuilts/misc/common/winscope/intDefMapping.json

• Upload the changes.

cd ./prebuilts/misc/common/winscope
repo start intdef-update
git commit -am "Update intdef mapping" "Test: N/A"
repo upload --cbr .

Building with internal extensions

Internal paths in vendor/ which are not available in AOSP must be replaced by stub files. See getWaylandSafePath for an example