How ADB Works

Get Code

git clone https://android.googlesource.com/platform/system/adb

Architecture

There are three components in ADB: Client, AdbServer, Adb Daemon. Client and AdbServer always run on your PC, Adb Daemon (adbd) run on your Android device.

Establish Connection

When you input adb connect <serial>, why connection state become device or offline. There are 1 + 2 * N threads in AdbServer, every connection has a atransport object, every transport has two threads.

Verify Auth Permission

ADB Daemon will do something to check auth permission before send CNXN Packet to AdbServer.

Execute Command

When you input adb -s <serial> <command>, command may be shell or others.