1*d57664e9SAndroid Build Coastguard Worker# dumpcoverage 2*d57664e9SAndroid Build Coastguard Worker 3*d57664e9SAndroid Build Coastguard Workerlibdumpcoverage.so is a JVMTI agent designed to dump coverage information for a process, where the binaries have been instrumented by JaCoCo. JaCoCo automatically starts recording data on process start, and we need a way to trigger the resetting or dumping of this data. 4*d57664e9SAndroid Build Coastguard Worker 5*d57664e9SAndroid Build Coastguard WorkerThe JVMTI agent is used to make the calls to JaCoCo in its process. 6*d57664e9SAndroid Build Coastguard Worker 7*d57664e9SAndroid Build Coastguard Worker# Usage 8*d57664e9SAndroid Build Coastguard Worker 9*d57664e9SAndroid Build Coastguard WorkerNote that these examples assume you have an instrumented build (userdebug_coverage). Here is, for example, how to dump coverage information regarding the default clock app. First some setup is necessary: 10*d57664e9SAndroid Build Coastguard Worker 11*d57664e9SAndroid Build Coastguard Worker``` 12*d57664e9SAndroid Build Coastguard Workeradb root # necessary to copy files in/out of the /data/data/{package} folder 13*d57664e9SAndroid Build Coastguard Workeradb shell 'mkdir /data/data/com.android.deskclock/folder-to-use' 14*d57664e9SAndroid Build Coastguard Worker``` 15*d57664e9SAndroid Build Coastguard Worker 16*d57664e9SAndroid Build Coastguard WorkerThen we can run the command to dump the data: 17*d57664e9SAndroid Build Coastguard Worker 18*d57664e9SAndroid Build Coastguard Worker``` 19*d57664e9SAndroid Build Coastguard Workeradb shell 'am attach-agent com.android.deskclock /system/lib/libdumpcoverage.so=dump:/data/data/com.android.deskclock/folder-to-use/coverage-file.ec' 20*d57664e9SAndroid Build Coastguard Worker``` 21*d57664e9SAndroid Build Coastguard Worker 22*d57664e9SAndroid Build Coastguard WorkerWe can also reset the coverage information with 23*d57664e9SAndroid Build Coastguard Worker 24*d57664e9SAndroid Build Coastguard Worker``` 25*d57664e9SAndroid Build Coastguard Workeradb shell 'am attach-agent com.android.deskclock /system/lib/libdumpcoverage.so=reset' 26*d57664e9SAndroid Build Coastguard Worker``` 27*d57664e9SAndroid Build Coastguard Worker 28*d57664e9SAndroid Build Coastguard Workerthen perform more actions, then dump the data again. To get the files, we can get 29*d57664e9SAndroid Build Coastguard Worker 30*d57664e9SAndroid Build Coastguard Worker``` 31*d57664e9SAndroid Build Coastguard Workeradb pull /data/data/com.android.deskclock/folder-to-use/coverage-file.ec ~/path-on-your-computer 32*d57664e9SAndroid Build Coastguard Worker``` 33*d57664e9SAndroid Build Coastguard Worker 34*d57664e9SAndroid Build Coastguard WorkerAnd you should have `coverage-file.ec` on your machine under the folder `~/path-on-your-computer` 35*d57664e9SAndroid Build Coastguard Worker 36*d57664e9SAndroid Build Coastguard Worker# Details 37*d57664e9SAndroid Build Coastguard Worker 38*d57664e9SAndroid Build Coastguard WorkerIn dump mode, the agent makes JNI calls equivalent to 39*d57664e9SAndroid Build Coastguard Worker 40*d57664e9SAndroid Build Coastguard Worker``` 41*d57664e9SAndroid Build Coastguard WorkerAgent.getInstance().getExecutionData(/*reset = */ false); 42*d57664e9SAndroid Build Coastguard Worker``` 43*d57664e9SAndroid Build Coastguard Worker 44*d57664e9SAndroid Build Coastguard Workerand then saves the result to a file specified by the passed in directory 45*d57664e9SAndroid Build Coastguard Worker 46*d57664e9SAndroid Build Coastguard WorkerIn reset mode, it makes a JNI call equivalent to 47*d57664e9SAndroid Build Coastguard Worker 48*d57664e9SAndroid Build Coastguard Worker``` 49*d57664e9SAndroid Build Coastguard WorkerAgent.getInstance().reset(); 50*d57664e9SAndroid Build Coastguard Worker``` 51