From 81d6032c43bee2400106e1d151cd002b0aaa9d5c Mon Sep 17 00:00:00 2001
From: Marc Weber <marco-oweber@gmx.de>
Date: Mon, 18 May 2009 12:01:31 +0000
Subject: [PATCH] Synced with trunk @ 15505

svn path=/nixos/branches/modular-nixos/; revision=15640
---
 installer/grub-menu-builder.sh    | 101 +++++++++++++++++++-----------
 system/switch-to-configuration.sh |   6 +-
 2 files changed, 69 insertions(+), 38 deletions(-)

diff --git a/installer/grub-menu-builder.sh b/installer/grub-menu-builder.sh
index 72635c364335..464fc94ce22c 100644
--- a/installer/grub-menu-builder.sh
+++ b/installer/grub-menu-builder.sh
@@ -15,6 +15,9 @@ bootMount="@bootMount@"
 if test -z "$bootMount"; then bootMount=/boot; fi
 
 
+echo "updating the Grub menu..."
+
+
 target=/boot/grub/menu.lst
 tmp=$target.tmp
 
@@ -27,14 +30,13 @@ GRUBEND
 
 if test -n "@grubSplashImage@"; then
     splashLocation=@grubSplashImage@
-    # !!! image in /nix/store doesn't seem to work
-    #if test -n "@copyKernels@"; then
-	cp -f $splashLocation /boot/background.xpm.gz
-	splashLocation="$bootMount/background.xpm.gz"
-    #fi
+    # Splash images in /nix/store don't seem to work, so copy them.
+    cp -f $splashLocation /boot/background.xpm.gz
+    splashLocation="$bootMount/background.xpm.gz"
     echo "splashimage $splashLocation" >> $tmp
 fi
 
+
 configurationCounter=0
 configurationLimit="@configurationLimit@"
 numAlienEntries=`cat <<EOF | egrep '^[[:space:]]*title' | wc -l
@@ -42,18 +44,48 @@ numAlienEntries=`cat <<EOF | egrep '^[[:space:]]*title' | wc -l
 EOF`
 
 if test $((configurationLimit+numAlienEntries)) -gt 190; then
-	configurationLimit=$((190-numAlienEntries));
+    configurationLimit=$((190-numAlienEntries));
 fi
 
+
+# Convert a path to a file in the Nix store such as
+# /nix/store/<hash>-<name>/file to <hash>-<name>-<file>.
+cleanName() {
+    local path="$1"
+    echo "$path" | sed 's|^/nix/store/||' | sed 's|/|-|g'
+}
+
+
+# Copy a file from the Nix store to /boot/kernels.
+declare -A filesCopied
+
+copyToKernelsDir() {
+    local src="$1"
+    local dst="/boot/kernels/$(cleanName $src)"
+    # Don't copy the file if $dst already exists.  This means that we
+    # have to create $dst atomically to prevent partially copied
+    # kernels or initrd if this script is ever interrupted.
+    if ! test -e $dst; then
+        local dstTmp=$dst.tmp.$$
+        cp $src $dstTmp
+        mv $dstTmp $dst
+    fi
+    filesCopied[$dst]=1
+    result=$dst
+}
+
+
+# Add an entry for a configuration to the Grub menu, and if
+# appropriate, copy its kernel and initrd to /boot/kernels.
 addEntry() {
     local name="$1"
     local path="$2"
     local shortSuffix="$3"
 
     configurationCounter=$((configurationCounter + 1))
-    if test $configurationCounter -gt @configurationLimit@ ; then
-	    return
-    fi;
+    if test $configurationCounter -gt @configurationLimit@; then
+	return
+    fi
 
     if ! test -e $path/kernel -a -e $path/initrd; then
         return
@@ -63,10 +95,10 @@ addEntry() {
     local initrd=$(readlink -f $path/initrd)
 
     if test "$path" = "$default"; then
-	    cp "$kernel" /boot/nixos-kernel
-	    cp "$initrd" /boot/nixos-initrd
-	    cp "$(readlink -f "$path/init")" /boot/nixos-init
-	    cat > /boot/nixos-grub-config <<EOF
+	cp "$kernel" /boot/nixos-kernel
+	cp "$initrd" /boot/nixos-initrd
+	cp "$(readlink -f "$path/init")" /boot/nixos-init
+	cat > /boot/nixos-grub-config <<EOF
 	title Emergency boot
 	kernel ${bootMount:-/boot}/nixos-kernel systemConfig=$(readlink -f "$path") init=/boot/nixos-init $(cat "$path/kernel-params")
 	initrd ${bootMount:-/boot}/nixos-initrd
@@ -74,30 +106,21 @@ EOF
     fi
 
     if test -n "@copyKernels@"; then
-        local kernel2=/boot/kernels/$(echo $kernel | sed 's^/^-^g')
-        if ! test -e $kernel2; then
-            cp $kernel $kernel2
-        fi
-        kernel=$kernel2
-
-        local initrd2=/boot/kernels/$(echo $initrd | sed 's^/^-^g')
-        if ! test -e $initrd2; then
-            cp $initrd $initrd2
-        fi
-        initrd=$initrd2
-
-        if test -n "$bootMount"; then
-          kernel=$(echo $kernel2 | sed -e "s^/boot^$bootMount^")
-          initrd=$(echo $initrd2 | sed -e "s^/boot^$bootMount^")
-        fi
+        copyToKernelsDir $kernel; kernel=$result
+        copyToKernelsDir $initrd; initrd=$result
+    fi
+    
+    if test -n "$bootMount"; then
+        kernel=$(echo $kernel | sed -e "s^/boot^$bootMount^")
+        initrd=$(echo $initrd | sed -e "s^/boot^$bootMount^")
     fi
     
     local confName=$(if test -e $path/configuration-name; then 
 	cat $path/configuration-name; 
-    fi);
-    if test -n "$confName" ; then
-	name="$confName $3";
-    fi;
+    fi)
+    if test -n "$confName"; then
+	name="$confName $3"
+    fi
 
     cat >> $tmp << GRUBEND
 
@@ -108,11 +131,11 @@ GRUBEND
 }
 
 
-rm -rf /boot/kernels
 if test -n "@copyKernels@"; then
     mkdir -p /boot/kernels
 fi
 
+
 # Additional entries specified verbatim by the configuration.
 extraGrubEntries=`cat <<EOF
 @extraGrubEntries@
@@ -135,11 +158,11 @@ for link in $((ls -d $default/fine-tune/* ) | sort -n); do
     date=$(stat --printf="%y\n" $link | sed 's/\..*//')
     addEntry "NixOS - variation" $link ""
 done
+
 for generation in $(
     (cd /nix/var/nix/profiles && ls -d system-*-link) \
     | sed 's/system-\([0-9]\+\)-link/\1/' \
     | sort -n -r); do
-    echo $generation
     link=/nix/var/nix/profiles/system-$generation-link
     date=$(stat --printf="%y\n" $link | sed 's/\..*//')
     kernelVersion=$(cd $(dirname $(readlink -f $link/kernel))/lib/modules && echo *)
@@ -150,3 +173,11 @@ done
 # Atomically update /boot/grub/menu.lst.  !!! should do an fsync()
 # here on $tmp, especially on ext4.
 mv $tmp $target
+
+
+# Remove obsolete files from /boot/kernels.
+for fn in $(ls /boot/kernels/*); do
+    if ! test "${filesCopied[$fn]}" = 1; then
+        rm -vf -- "$fn"
+    fi
+done
diff --git a/system/switch-to-configuration.sh b/system/switch-to-configuration.sh
index eaeb3106afd9..6cd5d6aff97d 100644
--- a/system/switch-to-configuration.sh
+++ b/system/switch-to-configuration.sh
@@ -50,8 +50,8 @@ EOF
     oldEvents=$(readlink -f /etc/event.d || true)
     newEvents=$(readlink -f @out@/etc/event.d)
 
-    echo "old: $oldEvents"
-    echo "new: $newEvents"
+    #echo "old: $oldEvents"
+    #echo "new: $newEvents"
 
     stopJob() {
         local job=$1
@@ -73,7 +73,7 @@ EOF
 
     # Activate the new configuration (i.e., update /etc, make
     # accounts, and so on).
-    echo "Activating the configuration..."
+    echo "activating the configuration..."
     @out@/activate @out@
 
     # Make Upstart reload its events.  !!! Should wait until it has