X-Git-Url: https://git.rohieb.name/openwrt.git/blobdiff_plain/143496aa4d31c79178027f9838e8cb3a659969f5..002c3c665289b52eb20fd899fd3561e7f9d9e073:/docs/build.tex

diff --git a/docs/build.tex b/docs/build.tex
index 03bd1a967..6e1539acf 100644
--- a/docs/build.tex
+++ b/docs/build.tex
@@ -41,11 +41,10 @@ So let's take a look at OpenWrt and see how this all works.
 
 \subsubsection{Download OpenWrt}
 
-This article refers to the "Kamikaze" branch of OpenWrt, which can be downloaded via
-subversion using the following command:
+OpenWrt can be downloaded via subversion using the following command:
 
 \begin{Verbatim}
-$ svn checkout https://svn.openwrt.org/openwrt/trunk kamikaze
+$ svn checkout svn://svn.openwrt.org/openwrt/trunk openwrt-trunk
 \end{Verbatim}
 
 Additionally, there is a trac interface on \href{https://dev.openwrt.org/}{https://dev.openwrt.org/}
@@ -65,41 +64,43 @@ There are four key directories in the base:
 
 \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
 symlinked into the main trunk. Once you do that, the packages will show up in the menu for
-configuration. From kamikaze you would do something like this:
+configuration. 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
@@ -108,12 +109,12 @@ directory which is broken down by platform \textit{<arch>} and contains the patc
 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}
 
@@ -171,7 +172,7 @@ of noise caused by the compile output. To see the full output, run the command
 "\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.
 
@@ -180,7 +181,7 @@ 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}
@@ -202,13 +203,6 @@ simplifies the entire ordeal.
 Here for example, is \texttt{package/bridge/Makefile}:
 
 \begin{Verbatim}[frame=single,numbers=left]
-#
-# Copyright (C) 2006 OpenWrt.org
-#
-# This is free software, licensed under the GNU General Public License v2.
-# See /LICENSE for more information.
-#
-# $Id: Makefile 5624 2006-11-23 00:29:07Z nbd $
 
 include $(TOPDIR)/rules.mk
 
@@ -229,12 +223,14 @@ define Package/bridge
   SECTION:=net
   CATEGORY:=Base system
   TITLE:=Ethernet bridging configuration utility
-  DESCRIPTION:=\
-    Manage ethernet bridging: a way to connect networks together to \\\
-    form a larger network.
   URL:=http://bridge.sourceforge.net/
 endef
 
+define Package/bridge/description
+  Manage ethernet bridging: 
+  a way to connect networks together to form a larger network.
+endef
+
 define Build/Configure
     $(call Build/Configure/Default, \
         --with-linux-headers="$(LINUX_DIR)" \
@@ -296,7 +292,7 @@ directly as the Nth argument to \texttt{BuildPackage}.
 
     \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} \\
@@ -309,6 +305,9 @@ directly as the Nth argument to \texttt{BuildPackage}.
             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):} \\
@@ -346,6 +345,19 @@ directly as the Nth argument to \texttt{BuildPackage}.
 	   Contains all environment variables that are passed to the make command
    \end{itemize}
 
+\textbf{\texttt{Build/InstallDev} (optional):} \\
+	If your package provides a library that needs to be made available to other packages,
+	you can use the \texttt{Build/InstallDev} template to copy it into the staging directory
+	which is used to collect all files that other packages might depend on at build time.
+	When it is called by the build system, two parameters are passed to it. \texttt{\$(1)} points to
+	the regular staging dir, typically \texttt{staging\_dir/\textit{ARCH}}, while \texttt{\$(2)} points
+	to \texttt{staging\_dir/host}. The host staging dir is only used for binaries, which are
+	to be executed or linked against on the host and its \texttt{bin/} subdirectory is included
+	in the \texttt{PATH} which is passed down to the build system processes.
+	Please use \texttt{\$(1)} and \texttt{\$(2)} here instead of the build system variables
+	\texttt{\$(STAGING\_DIR)} and \texttt{\$(STAGING\_DIR\_HOST)}, because the build system behavior
+	when staging libraries might change in the future to include automatic uninstallation.
+
 \textbf{\texttt{Package/\textit{<name>}/install}:} \\
    A set of commands to copy files out of the compiled source and into the ipkg
    which is represented by the \texttt{\$(1)} directory. Note that there are currently
@@ -373,6 +385,58 @@ After you have created your \texttt{package/\textit{<name>}/Makefile}, the new p
 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.
@@ -384,13 +448,6 @@ For external kernel modules, you can add them to the build system just like if t
 Here for instance the Makefile for the I2C subsytem kernel modules :
 
 \begin{Verbatim}[frame=single,numbers=left]
-#
-# Copyright (C) 2006 OpenWrt.org
-#
-# This is free software, licensed under the GNU General Public License v2.
-# See /LICENSE for more information.
-#
-# $Id $
 
 I2CMENU:=I2C Bus
 
@@ -398,8 +455,7 @@ define KernelPackage/i2c-core
   TITLE:=I2C support
   DESCRIPTION:=Kernel modules for i2c support
   SUBMENU:=$(I2CMENU)
-  KCONFIG:=$(CONFIG_I2C_CORE) \
-        $(CONFIG_I2C_DEV)
+  KCONFIG:=CONFIG_I2C_CORE CONFIG_I2C_DEV
   FILES:=$(MODULES_DIR)/kernel/drivers/i2c/*.$(LINUX_KMOD_SUFFIX)
   AUTOLOAD:=$(call AutoLoad,50,i2c-core i2c-dev)
 endef
@@ -459,14 +515,14 @@ shortcuts you can take. Instead of waiting for make to get to your package, you
 run one of the following:
 
 \begin{itemize}
-    \item \texttt{make package/\textit{<name>}-clean V=99}
-    \item \texttt{make package/\textit{<name>}-install V=99}
+    \item \texttt{make package/\textit{<name>}/clean V=99}
+    \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.
@@ -474,8 +530,65 @@ it will remove the old sources and unpack a fresh copy.
 Other useful targets include:
 
 \begin{itemize}
-    \item \texttt{make package/\textit{<name>}-prepare V=99}
-    \item \texttt{make package/\textit{<name>}-compile V=99}
-    \item \texttt{make package/\textit{<name>}-configure V=99}
+    \item \texttt{make package/\textit{<name>}/prepare V=99}
+    \item \texttt{make package/\textit{<name>}/compile V=99}
+    \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}
