From 131ba6fed71615f10f662a66357cfdddec16026d Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Wed, 6 Aug 2008 14:30:46 +0000
Subject: [PATCH] add script for managing 'build environments'
(.config+files/), including documentation
SVN-Revision: 12212
---
docs/build.tex | 57 +++++++++++++
scripts/env | 219 +++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 276 insertions(+)
create mode 100755 scripts/env
diff --git a/docs/build.tex b/docs/build.tex
index 54d31c582b..cc7f5fd2c8 100644
--- a/docs/build.tex
+++ b/docs/build.tex
@@ -483,3 +483,60 @@ Other useful targets include:
\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}
+ \texttt{./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}
diff --git a/scripts/env b/scripts/env
new file mode 100755
index 0000000000..d783e20efe
--- /dev/null
+++ b/scripts/env
@@ -0,0 +1,219 @@
+#!/usr/bin/env bash
+BASEDIR="$PWD"
+ENVDIR="$PWD/env"
+
+usage() {
+ cat <<EOF
+Usage: $0 [options] <command> [arguments]
+Commands:
+ help This help text
+ list List environments
+ clear Delete all environment and revert to flat config/files
+ new <name> Create a new environment
+ switch <name> Switch to a different environment
+ delete <name> Delete an environment
+ rename <newname> Rename the current environment
+ diff Show differences between current state and environment
+ save Save your changes to the environment
+ revert Revert your changes since last save
+
+Options:
+
+EOF
+ exit ${1:-1}
+}
+
+error() {
+ echo "$0: $*"
+ exit 1
+}
+
+ask_bool() {
+ local DEFAULT="$1"; shift
+ local def defstr val
+ case "$DEFAULT" in
+ 1) def=0; defstr="Y/n";;
+ 0) def=1; defstr="y/N";;
+ *) def=; defstr="y/n";;
+ esac
+ while [ -z "$val" ]; do
+ local VAL
+
+ echo -n "$* ($defstr): "
+ read VAL
+ case "$VAL" in
+ y*|Y*) val=0;;
+ n*|N*) val=1;;
+ *) val="$def";;
+ esac
+ done
+ return "$val"
+}
+
+env_init() {
+ local CREATE="$1"
+ if [ -z "$CREATE" ]; then
+ [ -d "$ENVDIR" ] || exit 0
+ fi
+ [ -x "$(which git 2>/dev/null)" ] || error "Git is not installed"
+ mkdir -p "$ENVDIR" || error "Failed to create the environment directory"
+ cd "$ENVDIR" || error "Failed to switch to the environment directory"
+ [ -d .git ] || {
+ git init &&
+ touch .config &&
+ mkdir files &&
+ git-add . &&
+ git-commit -q -m "Initial import"
+ } || {
+ rm -rf .git
+ error "Failed to initialize the environment directory"
+ }
+}
+
+env_sync_data() {
+ [ \! -L "$BASEDIR/.config" -a -f "$BASEDIR/.config" ] && mv "$BASEDIR/.config" "$ENVDIR"
+ git-add .
+ git-add -u
+}
+
+env_sync() {
+ local STR="$1"
+ env_sync_data
+ git-commit -m "${STR:-Update} at $(date)"
+}
+
+env_link_config() {
+ rm -f "$BASEDIR/.config"
+ ln -s env/.config "$BASEDIR/.config"
+ mkdir -p "$ENVDIR/files"
+ [ -L "$BASEDIR/files" ] || ln -s env/files "$BASEDIR/files"
+}
+
+env_do_reset() {
+ git-reset --hard HEAD
+ git-clean -d -f
+}
+
+env_list() {
+ env_init
+ git-branch | grep -vE '^. master$'
+}
+
+env_diff() {
+ env_init
+ env_sync_data
+ git-diff --cached
+}
+
+env_save() {
+ env_init
+ env_sync
+ env_link_config
+}
+
+env_revert() {
+ env_init
+ env_do_reset
+ env_link_config
+}
+
+env_ask_sync() {
+ LINES="$(env_diff | wc -l)" # implies env_init
+ [ "$LINES" -gt 0 ] && {
+ if ask_bool 1 "Do you want to save your changes"; then
+ env_sync
+ else
+ env_sync_data
+ env_do_reset
+ fi
+ }
+}
+
+env_clear() {
+ env_init
+ [ -L "$BASEDIR/.config" ] && rm -f "$BASEDIR/.config"
+ [ -L "$BASEDIR/files" ] && rm -f "$BASEDIR/files"
+ [ -f "$ENVDIR/.config" ] || ( cd "$ENVDIR/files" && find | grep -vE '^\.$' > /dev/null )
+ env_sync_data
+ if ask_bool 1 "Do you want to keep your current config and files"; then
+ mkdir -p "$BASEDIR/files"
+ cp -a "$ENVDIR/files/*" "$BASEDIR/files" 2>/dev/null >/dev/null
+ cp "$ENVDIR/.config" "$BASEDIR/"
+ else
+ rm -rf "$BASEDIR/files" "$BASEDIR/.config"
+ fi
+ cd "$BASEDIR"
+ rm -rf "$ENVDIR"
+}
+
+env_delete() {
+ local name="${1##*/}"
+ [ -z "$name" ] && usage
+ [ -f "$envdir/.git/refs/heads/$name" ] || error "environment '$name' not found"
+ branch="$(git-branch | grep '^\* ' | awk '{print $2}')"
+ [ "$name" = "branch" ] && error "cannot delete the currently selected environment"
+ git-branch -D "$name"
+}
+
+env_switch() {
+ local name="${1##*/}"
+ [ -z "$name" ] && usage
+ [ -f "$envdir/.git/refs/heads/$name" ] || error "environment '$name' not found"
+
+ env_init
+ env_ask_sync
+ git-checkout "$NAME"
+ env_link_config
+}
+
+env_rename() {
+ local NAME="${1##*/}"
+ env_init
+ git-branch -m "$NAME"
+}
+
+env_new() {
+ local NAME="$1"
+ local branch
+ local from="master"
+
+ [ -z "$NAME" ] && usage
+ env_init 1
+
+ branch="$(git-branch | grep '^\* ' | awk '{print $2}')"
+ if [ -n "$branch" -a "$branch" != "master" ]; then
+ env_ask_sync
+ if ask_bool 0 "Do you want to clone the current environment?"; then
+ from="$branch"
+ fi
+ rm -f "$BASEDIR/.config" "$BASEDIR/files"
+ fi
+ git-checkout -b "$1" "$from"
+ if [ -f "$BASEDIR/.config" -o -d "$BASEDIR/files" ]; then
+ if ask_bool 1 "Do you want to keep your current config and files?"; then
+ [ -d "$BASEDIR/files" -a \! -L "$BASEDIR/files" ] && {
+ mv "$BASEDIR/files/"* "$ENVDIR/" 2>/dev/null
+ rmdir "$BASEDIR/files"
+ }
+ env_sync
+ else
+ rm -rf "$BASEDIR/.config" "$BASEDIR/files"
+ fi
+ fi
+ env_link_config
+}
+
+COMMAND="$1"; shift
+case "$COMMAND" in
+ help) usage 0;;
+ new) env_new "$@";;
+ list) env_list "$@";;
+ clear) env_clear "$@";;
+ switch) env_switch "$@";;
+ delete) env_delete "$@";;
+ rename) env_rename "$@";;
+ diff) env_diff "$@";;
+ save) env_save "$@";;
+ revert) env_revert "$@";;
+ *) usage;;
+esac
--
GitLab