subversion using the following command:
\begin{Verbatim}
-$ svn checkout https://svn.openwrt.org/openwrt/trunk kamikaze
+$ svn checkout svn://svn.openwrt.org/openwrt/trunk kamikaze
\end{Verbatim}
Additionally, there is a trac interface on \href{https://dev.openwrt.org/}{https://dev.openwrt.org/}
\texttt{tools} and \texttt{toolchain} refer to common tools which will be
used to build the firmware image, the compiler, and the C library.
-The result of this is three new directories, \texttt{tool\_build}, which is a temporary
-directory for building the target independent tools, \texttt{toolchain\_build\_\textit{<arch>}}
+The result of this is three new directories, \texttt{build\_dir/host}, which is a temporary
+directory for building the target independent tools, \texttt{build\_dir/toolchain-\textit{<arch>}*}
which is used for building the toolchain for a specific architecture, and
-\texttt{staging\_dir\_\textit{<arch>}} where the resulting toolchain is installed.
+\texttt{staging\_dir/toolchain-\textit{<arch>}*} where the resulting toolchain is installed.
You will not need to do anything with the toolchain directory unless you intend to
add a new version of one of the components above.
\begin{itemize}
- \item \texttt{tool\_build}
- \item \texttt{toolchain\_build\_\textit{<arch>}}
+ \item \texttt{build\_dir/host}
+ \item \texttt{build\_dir/toolchain-\textit{<arch>}*}
\end{itemize}
\texttt{package} is for exactly that -- packages. In an OpenWrt firmware, almost everything
is an \texttt{.ipk}, a software package which can be added to the firmware to provide new
features or removed to save space. Note that packages are also maintained outside of the main
-trunk and can be obtained from subversion at the following location:
+trunk and can be obtained from subversion using the package feeds system:
\begin{Verbatim}
-$ svn checkout https://svn.openwrt.org/openwrt/packages packages
+$ ./scripts/feeds update
\end{Verbatim}
Those packages can be used to extend the functionality of the build system and need to be
configuration. From kamikaze you would do something like this:
\begin{Verbatim}
-$ ls
-kamikaze packages
-$ ln -s packages/net/nmap kamikaze/package/nmap
+$ ./scripts/feeds search nmap
+Search results in feed 'packages':
+nmap Network exploration and/or security auditing utility
+
+$ ./scripts/feeds install nmap
\end{Verbatim}
To include all packages, issue the following command:
\begin{Verbatim}
-$ ln -s packages/*/* kamikaze/package/
+$ make package/symlinks
\end{Verbatim}
\texttt{target} refers to the embedded platform, this contains items which are specific to
kernel, profile config, for a particular platform. There's also the "\texttt{target/image}" directory
which describes how to package a firmware for a specific platform.
-Both the target and package steps will use the directory "\texttt{build\_\textit{<arch>}}"
+Both the target and package steps will use the directory "\texttt{build\_dir/\textit{<arch>}}"
as a temporary directory for compiling. Additionally, anything downloaded by the toolchain,
target or package steps will be placed in the "\texttt{dl}" directory.
\begin{itemize}
- \item \texttt{build\_\textit{<arch>}}
+ \item \texttt{build\_dir/\textit{<arch>}}
\item \texttt{dl}
\end{itemize}
"\texttt{make V=99}".
During the build process, buildroot will download all sources to the "\texttt{dl}"
-directory and will start patching and compiling them in the "\texttt{build\_\textit{<arch>}}"
+directory and will start patching and compiling them in the "\texttt{build\_dir/\textit{<arch>}}"
directory. When finished, the resulting firmware will be in the "\texttt{bin}" directory
and packages will be in the "\texttt{bin/packages}" directory.
One of the things that we've attempted to do with OpenWrt's template system is make it
incredibly easy to port software to OpenWrt. If you look at a typical package directory
-in OpenWrt you'll find two things:
+in OpenWrt you'll find several things:
\begin{itemize}
\item \texttt{package/\textit{<name>}/Makefile}
Here for example, is \texttt{package/bridge/Makefile}:
\begin{Verbatim}[frame=single,numbers=left]
-# $Id: Makefile 5624 2006-11-23 00:29:07Z nbd $
include $(TOPDIR)/rules.mk
\begin{itemize}
\item \texttt{SECTION} \\
- The type of package (currently unused)
+ The section of package (currently unused)
\item \texttt{CATEGORY} \\
Which menu it appears in menuconfig: Network, Sound, Utilities, Multimedia ...
\item \texttt{TITLE} \\
Which packages must be built/installed before this package. To reference a dependency defined in the
same Makefile, use \textit{<dependency name>}. If defined as an external package, use
\textit{+<dependency name>}. For a kernel version dependency use: \textit{@LINUX\_2\_<minor version>}
+ \item \texttt{BUILDONLY} (optional) \\
+ Set this option to 1 if you do NOT want your package to appear in menuconfig.
+ This is useful for packages which are only used as build dependencies.
\end{itemize}
\textbf{\texttt{Package/\textit{<name>}/conffiles} (optional):} \\
will automatically show in the menu the next time you run "make menuconfig" and if selected
will be built automatically the next time "\texttt{make}" is run.
+\subsection{Creating binary packages}
+
+You might want to create binary packages and include them in the resulting images as packages.
+To do so, you can use the following template, which basically sets to nothing the Configure and
+Compile templates.
+
+\begin{Verbatim}[frame=single,numbers=left]
+
+include $(TOPDIR)/rules.mk
+
+PKG_NAME:=binpkg
+PKG_VERSION:=1.0
+PKG_RELEASE:=1
+
+PKG_SOURCE:=binpkg-$(PKG_VERSION).tar.gz
+PKG_SOURCE_URL:=http://server
+PKG_MD5SUM:=9b7dc52656f5cbec846a7ba3299f73bd
+PKG_CAT:=zcat
+
+include $(INCLUDE_DIR)/package.mk
+
+define Package/binpkg
+ SECTION:=net
+ CATEGORY:=Network
+ TITLE:=Binary package
+endef
+
+define Package/bridge/description
+ Binary package
+endef
+
+define Build/Configure
+endef
+
+define Build/Compile
+endef
+
+define Package/bridge/install
+ $(INSTALL_DIR) $(1)/usr/sbin
+ $(INSTALL_BIN) $(PKG_BUILD_DIR)/* $(1)/usr/sbin/
+endef
+
+$(eval $(call BuildPackage,bridge))
+\end{Verbatim}
+
+Provided that the tarball which contains the binaries reflects the final
+directory layout (/usr, /lib ...), it becomes very easy to get your package
+look like one build from sources.
+
+Note that using the same technique, you can easily create binary pcakages
+for your proprietary kernel modules as well.
+
\subsection{Creating kernel modules packages}
The OpenWrt distribution makes the distinction between two kind of kernel modules, those coming along with the mainline kernel, and the others available as a separate project. We will see later that a common template is used for both of them.
Here for instance the Makefile for the I2C subsytem kernel modules :
\begin{Verbatim}[frame=single,numbers=left]
-# $Id $
I2CMENU:=I2C Bus
\item \texttt{make package/\textit{<name>}/install V=99}
\end{itemize}
-Another nice trick is that if the source directory under \texttt{build\_\textit{<arch>}}
+Another nice trick is that if the source directory under \texttt{build\_dir/\textit{<arch>}}
is newer than the package directory, it won't clobber it by unpacking the sources again.
If you were working on a patch you could simply edit the sources under the
-\texttt{build\_\textit{<arch>}/\textit{<source>}} directory and run the install command above,
+\texttt{build\_dir/\textit{<arch>}/\textit{<source>}} directory and run the install command above,
when satisfied, copy the patched sources elsewhere and diff them with the unpatched
sources. A warning though - if you go modify anything under \texttt{package/\textit{<name>}}
it will remove the old sources and unpack a fresh copy.
\item \texttt{make package/\textit{<name>}/configure V=99}
\end{itemize}
+
+\subsection{Using build environments}
+OpenWrt provides a means of building images for multiple configurations
+which can use multiple targets in one single checkout. These \emph{environments}
+store a copy of the .config file generated by \texttt{make menuconfig} and the contents
+of the \texttt{./files} folder.
+The script \texttt{./scripts/env} is used to manage these environments, it uses
+\texttt{git} (which needs to be installed on your system) as backend for version control.
+
+The command
+\begin{Verbatim}
+ ./scripts/env help
+\end{Verbatim}
+produces a short help text with a list of commands.
+
+To create a new environment named \texttt{current}, run the following command
+\begin{Verbatim}
+ ./scripts/env new current
+\end{Verbatim}
+This will move your \texttt{.config} file and \texttt{./files} (if it exists) to
+the \texttt{env/} subdirectory and create symlinks in the base folder.
+
+After running make menuconfig or changing things in files/, your current state will
+differ from what has been saved before. To show these changes, use:
+\begin{Verbatim}
+ ./scripts/env diff
+\end{Verbatim}
+
+If you want to save these changes, run:
+\begin{Verbatim}
+ ./scripts/env save
+\end{Verbatim}
+If you want to revert your changes to the previously saved copy, run:
+\begin{Verbatim}
+ ./scripts/env revert
+\end{Verbatim}
+
+If you want, you can now create a second environment using the \texttt{new} command.
+It will ask you whether you want to make it a clone of the current environment (e.g.
+for minor changes) or if you want to start with a clean version (e.g. for selecting
+a new target).
+
+To switch to a different environment (e.g. \texttt{test1}), use:
+\begin{Verbatim}
+ ./scripts/env switch test1
+\end{Verbatim}
+
+To rename the current branch to a new name (e.g. \texttt{test2}), use:
+\begin{Verbatim}
+ ./scripts/env rename test2
+\end{Verbatim}
+
+If you want to get rid of environment switching and keep everything in the base directory
+again, use:
+\begin{Verbatim}
+ ./scripts/env clear
+\end{Verbatim}