yocto：bitbake单独编译某个模块的方法

在yocto编译环境中如果想单独编译某个模块

可以在已经搭建好的yocto编译环境中使用如下命令

Yocto中对于不同的Package，有不同的task，即可以执行不同的操作，有一些是所有包共通的，例如clean，build等。

我们可以使用下面命令来查看一个包都有哪些可执行的task：

bitbake Package -c listtasks

如：bitbake core-image-weston -c listtasks

有以下结果：

1.  
   Initialising tasks: 100% |#################################################################################################################################################################| Time: 0:00:07
2.  
   NOTE: Executing RunQueue Tasks
3.  
   do_build Default task for a recipe - depends on all other normal tasks required to 'build' a recipe
4.  
   do_checkuri Validates the SRC_URI value
5.  
   do_checkuriall Validates the SRC_URI value for all recipes required to build a target
6.  
   do_clean Removes all output files for a target
7.  
   do_cleanall Removes all output files, shared state cache, and downloaded source files for a target
8.  
   do_cleansstate Removes all output files and shared state cache for a target
9.  
   do_compile Compiles the source in the compilation directory
10.  
    do_configure Configures the source by enabling and disabling any build-time and configuration options for the software being built
11.  
    do_devpyshell Starts an interactive Python shell for development/debugging
12.  
    do_devshell Starts a shell with the environment set up for development/debugging
13.  
    do_dtv_checking
14.  
    do_fetch Fetches the source code
15.  
    do_fetchall Fetches all remote sources required to build a target
16.  
    do_image
17.  
    do_image_complete
18.  
    do_image_complete_setscene (setscene version)
19.  
    do_image_ext4
20.  
    do_image_qa
21.  
    do_image_qa_setscene (setscene version)
22.  
    do_image_tar
23.  
    do_install Copies files from the compilation directory to a holding area
24.  
    do_listtasks Lists all defined tasks for a target
25.  
    do_package Analyzes the content of the holding area and splits it into subsets based on available packages and files
26.  
    do_package_qa_setscene Runs QA checks on packaged files (setscene version)
27.  
    do_package_setscene Analyzes the content of the holding area and splits it into subsets based on available packages and files (setscene version)
28.  
    do_package_write_rpm Creates the actual RPM packages and places them in the Package Feed area
29.  
    do_package_write_rpm_setscene Creates the actual RPM packages and places them in the Package Feed area (setscene version)
30.  
    do_packagedata Creates package metadata used by the build system to generate the final packages
31.  
    do_packagedata_setscene Creates package metadata used by the build system to generate the final packages (setscene version)
32.  
    do_patch Locates patch files and applies them to the source code
33.  
    do_populate_lic Writes license information for the recipe that is collected later when the image is constructed
34.  
    do_populate_lic_setscene Writes license information for the recipe that is collected later when the image is constructed (setscene version)
35.  
    do_populate_sdk Creates the file and directory structure for an installable SDK
36.  
    do_populate_sdk_ext
37.  
    do_populate_sysroot_setscene Copies a subset of files installed by do_install into the sysroot in order to make them available to other recipes (setscene version)
38.  
    do_prepare_recipe_sysroot
39.  
    do_rootfs Creates the root filesystem (file and directory structure) for an image
40.  
    do_rootfs_wicenv
41.  
    do_sdk_depends
42.  
    do_unpack Unpacks the source code into a working directory
43.  
    do_vp9_checking
44.  
    NOTE: Tasks Summary: Attempted 1 tasks of which 0 didn't need to be rerun and all succeeded.
45.  
     

说明上面可以支持的CMD。

接着使用如下命令：

bitbake  -b bbfile -c CMD（before list）

1.  
   bitbake  -b pulseaudio_10.0 -c compile
2.  
    
3.  
   bitbake  -b pulseaudio_10.0 -c clean
4.  
    
5.  
   bitbake -b pulseaudio_10.0 -c build
6.  
    
7.  
   bitbake  -b pulseaudio_10.0 -c configure
8.  
    
9.  
   bitbake  -b pulseaudio_10.0 -c compile
10.  
     
11.  
    bitbake  -b pulseaudio_10.0 -c install

一般要在yocto的编译环境中打patch的方式如下：

1，bbappend文件的编译方式

在poky目录下的meta/conf/有个layer.conf配置文件

1.  
   # We have a conf and classes directory, add to BBPATH
2.  
   BBPATH .= ":${LAYERDIR}"
3.  
   # We have recipes-* directories, add to BBFILES
4.  
   BBFILES += "${LAYERDIR}/recipes-*/*/*.bb"
5.  
    
6.  
   BBFILES += "${LAYERDIR}/recipes-*/*/*.bbappend"

其中BBFILES为需要参加编译的文件。

2，基于模块的源码的patch

把patch文件放在模块的放patch的目录下

找到该模块的bb文件，参照已有的打patch的方式，添加自己的patch。

比如：

SRC_URI = "http://freedesktop.org/software/pulseaudio/releases/${BP}.tar.xz

           file://0001-padsp-Make-it-compile-on-musl.patch

           file://0001-client-conf-Add-allow-autospawn-for-root.patch

           file://pulseaudio-discuss-iochannel-don-t-use-variable-length-array-in-union.patch

           file://volatiles.04_pulse

           file://fix-add-connectionid-in-simple.patch（新增）