Android Studio在线调试之调试系统进程

1 建立AndroidStudio调试系统代码工程
1.1 建立工程时，无需编译整个系统代码。
1）只需要抽取调试的那几个java代码文件作为工程代码，引用或关联的系统jar包作为libs引用。
2）添加bootClasspath引用
3）可以删除android.sdk引用（根据需要与否）
ndk.dir=D\:\\AndroidSDK\\sdk\\ndk-bundle
sdk.dir=D\:\\AndroidSDK\\sdk

2、将1.1中编译的jar或apk或so替换到手机（debug版本）中，进行在线调试
2.1 选择正确的进程attach debug，一定要注意区分调试代码所在的系统进程，否则进入不了该断点。
Breakpoint at:
android.os.Process#killProcess
android.os.Process#killProcessQuiet
一运行就crash？Debug方式启动，然后AS attach debug
$ am start -D -W -n com.xxx/.yyy
$ am set-debug-app -w --persistent com.xxx
有native crash，产生tombstone日志，设置属性让debuggerd保留现场，然后 gdbclient.py -p PID
# setprop debug.debuggerd.wait_for_gdb true (7.0 8.0 9.0)
# setprop debug.db.uid 999999  (<= 6.0)
 

完整示例工程如下：
//================build.grade=============
apply plugin: 'java'

sourceCompatibility = JavaVersion.VERSION_1_8
targetCompatibility = JavaVersion.VERSION_1_8

def defaultEncoding = 'UTF-8'

sourceSets {
    main {
        java {
            srcDirs "$ANDROID_SRC_ROOT/frameworks/base/core/java",
                    "$ANDROID_SRC_ROOT/frameworks/base/media/java"
        }
    }
}

def CORE_JAR = "/system/framework/core-all.jar" // for Android N+; subst '/system/framework/core-oj.jar:/system/framework/core-libart.jar'

// QCOM
def BOOTCLASSPATH="/system/framework/com.qualcomm.qti.camera.jar:/system/framework/QPerformance.jar:/system/framework/core-oj.jar" //...
def SYSTEMSERVERCLASSPATH="/system/framework/services.jar:/system/framework/ethernet-service.jar" //...

// MTK
def EXTRA_CLASSPATH="/system/framework/android.hardware.light-V2.0-java.jar" //...
def full_clspath = CORE_JAR + ":" + BOOTCLASSPATH + ":" + SYSTEMSERVERCLASSPATH + ":" + EXTRA_CLASSPATH

sysLibs = files(full_clspath.split(":").collect {
    it.toString().replace("/system/framework", "qcomdev/sysLibs")
}).filter { it.exists() }

task fixModuleIml {
    ext.imlFile = projectDir.absolutePath + '/' + project.name + '.iml'
    inputs.file imlFile
    outputs.file imlFile

    try {
        if (!file(imlFile).exists())
            return

        // Parse the existing iml file
        def parse = new XmlParser().parse(imlFile)
        def moduleComponent = parse.component.find { it.@name == 'NewModuleRootManager' }

        // Check if it has already been fixed
        def orderEntries = moduleComponent.orderEntry

        // Determine the index of the jdk entry
        def jdkOrderEntry = orderEntries.find { it.@type == 'jdk' || it.@type == 'inheritedJdk' }
        if (jdkOrderEntry == null)
            return

        moduleComponent.children().remove(jdkOrderEntry)
        moduleComponent.children().add(jdkOrderEntry)

        // Write the fixed iml file
        def printer = new XmlNodePrinter(new PrintWriter(new FileWriter(imlFile)))
        printer.preserveWhitespace = true
        printer.print(parse)
    } catch (Exception e) {
        e.printStackTrace()
    }
}

compileJava {
    options.encoding = defaultEncoding

    def clspath = rootProject.ext.sysLibs.join(File.pathSeparator)
    println "bootClasspath before => " + options.bootClasspath
    options.bootClasspath = clspath
    println "bootClasspath after => " + options.bootClasspath
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    implementation  rootProject.ext.sysLibs
}