單獨編譯Android源代碼中的模塊

單獨編譯Android源代碼中的模塊

第一次下載好Android源代碼後，通過在Android源代碼工程下執行make命令，然後得到Android的系統鏡像system.img.
那麼當我們修改了android源代碼中某個模塊或者android源代碼工程中新增了一個自己的模塊。此時可以用make命令進行重新編譯，不過重新編譯比較浪費時間。google提供了另外的命令來進行單獨模塊的編譯，以及重新打包到system.img鏡像中的命令。

以下介紹單獨編譯android中模塊的命令，以及打包system.img的命令。

一、首先，執行腳本文件 envsetup.sh
該文件在Android源代碼目錄下的build目錄中，在這個shell 腳本中定義了 hmm,  croot, m, mm, mmm 等 function
執行命令如下：

fantasy@ubuntu:~/my_android$ . ./build/envsetup.sh

或者

fantasy@ubuntu:~/my_android$ source build/envsetup.sh

在當前目錄下輸入命令hmm(android 4.2版本使用hmm，其他版本貌似使用的是help命令)，顯示envsetup.sh提供命令

fantasy@ubuntu:~/my_android$ hmm
輸出為：

[plain]  Invoke ". build/envsetup.sh" from your shell to add the following functions to your environment: 
- lunch:   lunch <product_name>-<build_variant> 
- tapas:   tapas [<App1> <App2> ...] [arm|x86|mips] [eng|userdebug|user] 
- croot:   Changes directory to the top of the tree. 
- m:       Makes from the top of the tree. 
- mm:      Builds all of the modules in the current directory. 
- mmm:     Builds all of the modules in the supplied directories. 
- cgrep:   Greps on all local C/C++ files. 
- jgrep:   Greps on all local Java files. 
- resgrep: Greps on all local res/*.xml files. 
- godir:   Go to the directory containing a file. 
 
 
Look at the source to view more functions. The complete list is: 
addcompletions add_lunch_combo cgrep check_product check_variant choosecombo chooseproduct choosetype choosevariant cproj croot findmakefile gdbclient gdbwrapper get_abs_build_var getbugreports get_build_var getlastscreenshot getprebuilt getscreenshotpath getsdcardpath gettargetarch gettop godir hmm isviewserverstarted jgrep key_back key_home key_menu lunch _lunch m mangrep mm mmm pid printconfig print_lunch_menu resgrep runhat runtest set_java_home setpaths set_sequence_number set_stuff_for_environment settitle smoketest stacks startviewserver stopviewserver systemstack tapas tracedmdump 

Invoke ". build/envsetup.sh" from your shell to add the following functions to your environment:
- lunch:   lunch <product_name>-<build_variant>
- tapas:   tapas [<App1> <App2> ...] [arm|x86|mips] [eng|userdebug|user]
- croot:   Changes directory to the top of the tree.
- m:       Makes from the top of the tree.
- mm:      Builds all of the modules in the current directory.
- mmm:     Builds all of the modules in the supplied directories.
- cgrep:   Greps on all local C/C++ files.
- jgrep:   Greps on all local Java files.
- resgrep: Greps on all local res/*.xml files.
- godir:   Go to the directory containing a file.

Look at the source to view more functions. The complete list is:
addcompletions add_lunch_combo cgrep check_product check_variant choosecombo chooseproduct choosetype choosevariant cproj croot findmakefile gdbclient gdbwrapper get_abs_build_var getbugreports get_build_var getlastscreenshot getprebuilt getscreenshotpath getsdcardpath gettargetarch gettop godir hmm isviewserverstarted jgrep key_back key_home key_menu lunch _lunch m mangrep mm mmm pid printconfig print_lunch_menu resgrep runhat runtest set_java_home setpaths set_sequence_number set_stuff_for_environment settitle smoketest stacks startviewserver stopviewserver systemstack tapas tracedmdump

這些命令的具體用法，可以在命令的後面加-help來查看，這裡我們只關注mmm命令，也就是可以用它來編譯指定目錄的所有模塊，通常這個目錄只包含一個模塊。

注：

關於source
source 命令會把對應腳本中的內容讀取到當前的bash 解釋器中，在當前的執行環境中執行；其中定義的 function 以及通過 export 聲明的變量等在 source 執行結束之後依然存在於當前的bash 環境中。比如我們常用的 source .bashrc 或者 source /etc/profile 等目的是為了引用剛剛改動過的環境變量。

二、使用mmm編譯指定模塊
以下是通過mmm編譯android中自帶的一個試驗性的應用，命令如下：

fantasy@ubuntu:~/my_android$ mmm packages/experimental/CameraPreviewTest/

[plain]  ============================================ 
PLATFORM_VERSION_CODENAME=AOSP 
PLATFORM_VERSION=4.2.2.2.2.2.2.2.2.2 
TARGET_PRODUCT=full 
TARGET_BUILD_VARIANT=eng 
TARGET_BUILD_TYPE=release 
TARGET_BUILD_APPS= 
TARGET_ARCH=arm 
TARGET_ARCH_VARIANT=armv7-a 
TARGET_CPU_VARIANT=generic 
HOST_ARCH=x86 
HOST_OS=linux 
HOST_OS_EXTRA=Linux-3.8.9-x86_64-with-Ubuntu-10.04-lucid 
HOST_BUILD_TYPE=release 
BUILD_ID=OPENMASTER 
OUT_DIR=out 
============================================ 
make: Entering directory `/home/fantasy/my_android' 
target R.java/Manifest.java: VideoChatCameraTestApp (out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/src/R.stamp) 
Warning: AndroidManifest.xml already defines minSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest. 
Warning: AndroidManifest.xml already defines targetSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest. 
target Java: VideoChatCameraTestApp (out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes) 
Note: Some input files use or override a deprecated API. 
Note: Recompile with -Xlint:deprecation for details. 
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes-jarjar.jar 
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/emma_out b/classes-jarjar.jar 
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes.jar 
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates proguard.classes.jar 
target Dex: VideoChatCameraTestApp 
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates proguard.classes.dex 
target Package: VideoChatCameraTestApp (out/target/product/generic/obj/APPS/VideoChatCameraTestApp_intermediates/package.apk) 
Warning: AndroidManifest.xml already defines minSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest. 
Warning: AndroidManifest.xml already defines targetSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest. 
 'out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes.dex' as 'classes.dex'... 
Processing target/product/generic/obj/APPS/VideoChatCameraTestApp_intermediates/package.apk 
Done! 
Install: out/target/product/generic/data/app/VideoChatCameraTestApp.odex 
Install: out/target/product/generic/data/app/VideoChatCameraTestApp.apk 

============================================
PLATFORM_VERSION_CODENAME=AOSP
PLATFORM_VERSION=4.2.2.2.2.2.2.2.2.2
TARGET_PRODUCT=full
TARGET_BUILD_VARIANT=eng
TARGET_BUILD_TYPE=release
TARGET_BUILD_APPS=
TARGET_ARCH=arm
TARGET_ARCH_VARIANT=armv7-a
TARGET_CPU_VARIANT=generic
HOST_ARCH=x86
HOST_OS=linux
HOST_OS_EXTRA=Linux-3.8.9-x86_64-with-Ubuntu-10.04-lucid
HOST_BUILD_TYPE=release
BUILD_ID=OPENMASTER
OUT_DIR=out
============================================
make: Entering directory `/home/fantasy/my_android'
target R.java/Manifest.java: VideoChatCameraTestApp (out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/src/R.stamp)
Warning: AndroidManifest.xml already defines minSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest.
Warning: AndroidManifest.xml already defines targetSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest.
target Java: VideoChatCameraTestApp (out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes)
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes-jarjar.jar
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/emma_out b/classes-jarjar.jar
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes.jar
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates proguard.classes.jar
target Dex: VideoChatCameraTestApp
Copying: out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates proguard.classes.dex
target Package: VideoChatCameraTestApp (out/target/product/generic/obj/APPS/VideoChatCameraTestApp_intermediates/package.apk)
Warning: AndroidManifest.xml already defines minSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest.
Warning: AndroidManifest.xml already defines targetSdkVersion (in  http://schemas.android.com/apk/res/android); using existing value in manifest.
 'out/target/common/obj/APPS/VideoChatCameraTestApp_intermediates/classes.dex' as 'classes.dex'...
Processing target/product/generic/obj/APPS/VideoChatCameraTestApp_intermediates/package.apk
Done!
Install: out/target/product/generic/data/app/VideoChatCameraTestApp.odex
Install: out/target/product/generic/data/app/VideoChatCameraTestApp.apk
編譯完成之後，就可以在out/target/product/generic/data/app/VideoChatCameraTestApp.apk目錄下看到VideoChatCameraTestApp.apk文件了。

注：

Android系統自帶的App是放在目錄~/my_android/out/target/product/generic/system/app下。

另外，Android系統的一些可執行文件，例如：

C編譯的可執行文件，放在out/target/product/generic/system/bin目錄下，

動態鏈接庫文件放在out/target/product/generic/system/lib目錄下，

硬件抽象層（HAL）接口文件防砸out/target/product/generic/system/lib/hw目錄下。