| Message ID | 1393167879-16637-13-git-send-email-thomas.petazzoni@free-electrons.com |
|---|---|
| State | Accepted |
| Headers | show |
Thomas, All, On 2014-02-23 16:04 +0100, Thomas Petazzoni spake thusly: > Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> > --- > docs/manual/advanced.txt | 2 + > docs/manual/using-buildroot-development.txt | 84 +++++++++++++++++++++++++++++ > 2 files changed, 86 insertions(+) > create mode 100644 docs/manual/using-buildroot-development.txt > > diff --git a/docs/manual/advanced.txt b/docs/manual/advanced.txt > index 764b71a..fb337f5 100644 > --- a/docs/manual/advanced.txt > +++ b/docs/manual/advanced.txt > @@ -11,3 +11,5 @@ include::ccache-support.txt[] > include::download-location.txt[] > > include::package-make-target.txt[] > + > +include::using-buildroot-development.txt[] > diff --git a/docs/manual/using-buildroot-development.txt b/docs/manual/using-buildroot-development.txt > new file mode 100644 > index 0000000..3267302 > --- /dev/null > +++ b/docs/manual/using-buildroot-development.txt > @@ -0,0 +1,84 @@ > +// -*- mode:doc; -*- > +// vim: set syntax=asciidoc: > + > +Using Buildroot during development > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > + > +The normal operation of Buildroot is to download a tarball, extract > +it, configure, compile and install the software component found inside > +this tarball. The source code is extracted in > ++output/build/<package>-<name>+, which is a temporary directory: output/build/<package>-<version> > +whenever +make clean+ is used, this directory is entirely removed, and > +re-recreated at the next +make+ invocation. Even when a Git or > +Subversion repository is used as the input for the package source > +code, Buildroot creates a tarball out of it, and then behaves as it > +does normally with tarballs. normally does > +This behavior is well-suited when Buildroot is used mainly as an > +integration tool, to build and integrate all the components of an > +embedded Linux system. However, if one uses Buildroot during the > +development of certain components of the system, this behavior is not > +very convenient: one would instead like to make a small change to the > +source code of one package, and be able to quickly rebuild the system > +with Buildroot. > + > +Making changes directly in +output/build/<package>-<name>+ is not output/build/<package>-<version> > +appropriate solution, because this directory is removed on +make > +clean+. > + > +Therefore, Buildroot provides a specific mechanism for this use case: > +the +<pkg>_OVERRIDE_SRCDIR+ mechanism. Buildroot reads an _override_ > +file, which allows the user to tell Buildroot the location of the > +source for certain packages. By default this _override_ file is named > ++local.mk+ and located in the top directory of the Buildroot source > +tree, Wrong, now it is locate in $(CONFIG_DIR), that is, the directory where we have the .config file, since: b1e514d Config: default BR2_PACKAGE_OVERRIDE_FILE to $(CONFIG_DIR)/local.mk This is Buildroot's top dir when building in-tree, and for out-of-tree builds, it's in $(O). [--SNIP--] Otherwise, LGTM. Regards, Yann E. MORIN.
>>>>> "Yann" == Yann E MORIN <yann.morin.1998@free.fr> writes: Hi, >> +appropriate solution, because this directory is removed on +make >> +clean+. >> + >> +Therefore, Buildroot provides a specific mechanism for this use case: >> +the +<pkg>_OVERRIDE_SRCDIR+ mechanism. Buildroot reads an _override_ >> +file, which allows the user to tell Buildroot the location of the >> +source for certain packages. By default this _override_ file is named >> ++local.mk+ and located in the top directory of the Buildroot source >> +tree, > Wrong, now it is locate in $(CONFIG_DIR), that is, the directory where > we have the .config file, since: > b1e514d Config: default BR2_PACKAGE_OVERRIDE_FILE to $(CONFIG_DIR)/local.mk > This is Buildroot's top dir when building in-tree, and for out-of-tree > builds, it's in $(O). True, but that commit is only in next, and I imho think this series belongs on master, so I'll leave it for now.
On 2014-02-23 22:29 +0100, Peter Korsgaard spake thusly: > >>>>> "Yann" == Yann E MORIN <yann.morin.1998@free.fr> writes: > > Hi, > > >> +appropriate solution, because this directory is removed on +make > >> +clean+. > >> + > >> +Therefore, Buildroot provides a specific mechanism for this use case: > >> +the +<pkg>_OVERRIDE_SRCDIR+ mechanism. Buildroot reads an _override_ > >> +file, which allows the user to tell Buildroot the location of the > >> +source for certain packages. By default this _override_ file is named > >> ++local.mk+ and located in the top directory of the Buildroot source > >> +tree, > > > Wrong, now it is locate in $(CONFIG_DIR), that is, the directory where > > we have the .config file, since: > > b1e514d Config: default BR2_PACKAGE_OVERRIDE_FILE to $(CONFIG_DIR)/local.mk > > > This is Buildroot's top dir when building in-tree, and for out-of-tree > > builds, it's in $(O). > > True, but that commit is only in next, and I imho think this series > belongs on master, so I'll leave it for now. Right! In fact, I was looking at my tree, which has it. It's eda3d0e on -next. And I agree, this series belongs to master. We'll just have to remember it at merge time. Sorry for the disruption. Regards, Yann E. MORIN.
diff --git a/docs/manual/advanced.txt b/docs/manual/advanced.txt index 764b71a..fb337f5 100644 --- a/docs/manual/advanced.txt +++ b/docs/manual/advanced.txt @@ -11,3 +11,5 @@ include::ccache-support.txt[] include::download-location.txt[] include::package-make-target.txt[] + +include::using-buildroot-development.txt[] diff --git a/docs/manual/using-buildroot-development.txt b/docs/manual/using-buildroot-development.txt new file mode 100644 index 0000000..3267302 --- /dev/null +++ b/docs/manual/using-buildroot-development.txt @@ -0,0 +1,84 @@ +// -*- mode:doc; -*- +// vim: set syntax=asciidoc: + +Using Buildroot during development +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The normal operation of Buildroot is to download a tarball, extract +it, configure, compile and install the software component found inside +this tarball. The source code is extracted in ++output/build/<package>-<name>+, which is a temporary directory: +whenever +make clean+ is used, this directory is entirely removed, and +re-recreated at the next +make+ invocation. Even when a Git or +Subversion repository is used as the input for the package source +code, Buildroot creates a tarball out of it, and then behaves as it +does normally with tarballs. + +This behavior is well-suited when Buildroot is used mainly as an +integration tool, to build and integrate all the components of an +embedded Linux system. However, if one uses Buildroot during the +development of certain components of the system, this behavior is not +very convenient: one would instead like to make a small change to the +source code of one package, and be able to quickly rebuild the system +with Buildroot. + +Making changes directly in +output/build/<package>-<name>+ is not +appropriate solution, because this directory is removed on +make +clean+. + +Therefore, Buildroot provides a specific mechanism for this use case: +the +<pkg>_OVERRIDE_SRCDIR+ mechanism. Buildroot reads an _override_ +file, which allows the user to tell Buildroot the location of the +source for certain packages. By default this _override_ file is named ++local.mk+ and located in the top directory of the Buildroot source +tree, but a different location can be specified through the ++BR2_PACKAGE_OVERRIDE_FILE+ configuration option. + +In this _override_ file, Buildroot expects to find lines of the form: + +------------------ +<pkg1>_OVERRIDE_SRCDIR = /path/to/pkg1/sources +<pkg2>_OVERRIDE_SRCDIR = /path/to/pkg2/sources +------------------ + +For example: + +------------------ +LINUX_OVERRIDE_SRCDIR = /home/bob/linux/ +BUSYBOX_OVERRIDE_SRCDIR = /home/bob/busybox/ +------------------ + +When Buildroot finds that for a given package, an ++<pkg>_OVERRIDE_SRCDIR+ has been defined, it will no longer attempt to +download, extract and patch the package. Instead, it will directly use +the source code available in in the specified directory and +make +clean+ will not touch this directory. This allows to point Buildroot +to your own directories, that can be managed by Git, Subversion, or +any other version control system. To achieve this, Buildroot will use +_rsync_ to copy the source code of the component from the specified ++<pkg>_OVERRIDE_SRCDIR+ to +output/build/<package>-custom/+. + +This mechanism is best used in conjuction with the +make +<pkg>-rebuild+ and +make <pkg>-reconfigure+ targets. A +make +<pkg>-rebuild all+ sequence will _rsync_ the source code from ++<pkg>_OVERRIDE_SRCDIR+ to +output/build/<package>-custom+ (thanks to +_rsync_, only the modified files are copied), and restart the build +process of just this package. + +In the example of the +linux+ package above, the developer can then +make a source code change in +/home/bob/linux+ and then run: + +----------------------- +make linux-rebuild all +----------------------- + +and in a matter of seconds gets the updated Linux kernel image in ++output/images+. Similarly, a change can be made to the Busybox source +code in +/home/bob/busybox+, and after: + +----------------------- +make busybox-rebuild all +----------------------- + +the root filesystem image in +output/images+ contains the updated +Busybox.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> --- docs/manual/advanced.txt | 2 + docs/manual/using-buildroot-development.txt | 84 +++++++++++++++++++++++++++++ 2 files changed, 86 insertions(+) create mode 100644 docs/manual/using-buildroot-development.txt