From 893f13bb1490f1facd7750049cf67ed4ac143172 Mon Sep 17 00:00:00 2001
From: Michael Raskin <7c6f434c@mail.ru>
Date: Fri, 23 Oct 2009 20:30:12 +0000
Subject: [PATCH] Some boot optimisations attempted. My system boots a few
 times faster now, and I cannot see how these can break things.

svn path=/nixos/trunk/; revision=17946
---
 .../system/activation/activation-script.nix   | 11 ++-
 modules/system/activation/top-level.nix       |  4 +-
 modules/system/boot/stage-2-init.sh           |  1 +
 modules/system/etc/etc.nix                    | 32 ++------
 modules/system/etc/make-etc.sh                | 76 ++++++++++++++++++-
 5 files changed, 93 insertions(+), 31 deletions(-)

diff --git a/modules/system/activation/activation-script.nix b/modules/system/activation/activation-script.nix
index a62120363f25..2ca7dcc82e12 100644
--- a/modules/system/activation/activation-script.nix
+++ b/modules/system/activation/activation-script.nix
@@ -11,6 +11,7 @@ let
       text = ''
         #### actionScripts snippet ${a} :
         #    ========================================
+	echo "executing activation snippet ${a} at $(${pkgs.coreutils}/bin/date)"
         ${v.text}
       '';
     });
@@ -123,8 +124,14 @@ let
       # Set up Nix.
       mkdir -p /nix/etc/nix
       ln -sfn /etc/nix.conf /nix/etc/nix/nix.conf
-      chown root.nixbld /nix/store
-      chmod 1775 /nix/store
+      stat /nix/store/ | \
+        egrep \
+	  'Access: [(]1775/[-drwxt]*[)] *Uid: [(][0-9 ]*/ *root[)] *Gid: [(][0-9 ]*/ *nixbld[)]' \
+	  > /dev/null || {
+
+              chown root.nixbld /nix/store
+              chmod 1775 /nix/store
+      }
 
       # Nix initialisation.
       mkdir -m 0755 -p \
diff --git a/modules/system/activation/top-level.nix b/modules/system/activation/top-level.nix
index 609b11dd3d6d..50fbde63b88d 100644
--- a/modules/system/activation/top-level.nix
+++ b/modules/system/activation/top-level.nix
@@ -42,7 +42,9 @@ let
   # as you use, but with another kernel
   # !!! fix this
   children = map (x: ((import ../../../default.nix)
-    { configuration = x//{boot=((x.boot)//{grubDevice = "";});};}).system) 
+    { configuration = x//{boot=((x.boot)//
+    	{loader=x.boot.loader//{grub=x.boot.loader.grub//
+	{device = "";};};});};}).system)
     config.nesting.children;
 
 
diff --git a/modules/system/boot/stage-2-init.sh b/modules/system/boot/stage-2-init.sh
index 0cc09caebba9..1089526cf6b1 100644
--- a/modules/system/boot/stage-2-init.sh
+++ b/modules/system/boot/stage-2-init.sh
@@ -132,6 +132,7 @@ fi
 # Ensure that the module tools can find the kernel modules.
 export MODULE_DIR=@kernel@/lib/modules/
 
+echo "Running post-boot commands"
 
 # Run any user-specified commands.
 @shell@ @postBootCommands@
diff --git a/modules/system/etc/etc.nix b/modules/system/etc/etc.nix
index 4ae420017a57..35137597d040 100644
--- a/modules/system/etc/etc.nix
+++ b/modules/system/etc/etc.nix
@@ -41,6 +41,8 @@ let
 
     builder = ./make-etc.sh;
 
+    inherit (pkgs) coreutils;
+
     /* !!! Use toXML. */
     sources = map (x: x.source) config.environment.etc;
     targets = map (x: x.target) config.environment.etc;
@@ -61,33 +63,9 @@ in
       etc = pkgs.lib.fullDepEntry ''
         # Set up the statically computed bits of /etc.
         echo "setting up /etc..."
-        staticEtc=/etc/static
-        rm -f $staticEtc
-        ln -s ${makeEtc}/etc $staticEtc
-        for i in $(cd $staticEtc && find * -type l); do
-            mkdir -p /etc/$(dirname $i)
-            rm -f /etc/$i
-            if test -e "$staticEtc/$i.mode"; then
-                # Create a regular file in /etc.
-                cp $staticEtc/$i /etc/$i
-                chown 0.0 /etc/$i
-                chmod "$(cat "$staticEtc/$i.mode")" /etc/$i
-            else
-                # Create a symlink in /etc.
-                ln -s $staticEtc/$i /etc/$i
-            fi
-        done
-
-        # Remove dangling symlinks that point to /etc/static.  These are
-        # configuration files that existed in a previous configuration but not
-        # in the current one.  For efficiency, don't look under /etc/nixos
-        # (where all the NixOS sources live).
-        for i in $(find /etc/ \( -path /etc/nixos -prune \) -o -type l); do
-            target=$(readlink "$i")
-            if test "''${target:0:''${#staticEtc}}" = "$staticEtc" -a ! -e "$i"; then
-                rm -f "$i"
-            fi
-        done
+	/etc/kill-etc || true
+	${makeEtc}/bin/fill-etc
+	echo "/etc is set up"
       '' [
         "systemConfig"
         "defaultPath" # path to cp, chmod, chown
diff --git a/modules/system/etc/make-etc.sh b/modules/system/etc/make-etc.sh
index f05d74b55fcf..76ae97c6c65a 100644
--- a/modules/system/etc/make-etc.sh
+++ b/modules/system/etc/make-etc.sh
@@ -5,6 +5,61 @@ ensureDir $out/etc
 sources_=($sources)
 targets_=($targets)
 modes_=($modes)
+
+cat <<EOF >> fill-etc.c
+    #include <sys/types.h>
+    #include <sys/stat.h>
+    #include <unistd.h>
+    #include <stdio.h>
+    #include <stdlib.h>
+    #include <string.h>
+    #include <limits.h>
+    #include <sys/wait.h>
+
+    struct stat statBuffer;
+
+    void ensureDir(char* path) {
+        int i, j;
+        char pathBuffer[PATH_MAX];
+        statBuffer.st_mode = 0;
+        for (i=0; path[i]; i++) {
+            if (path[i]=='/') {
+                pathBuffer[i]=0;
+                mkdir(pathBuffer ,0755);
+		j = i;
+            }
+            pathBuffer[i]=path[i];
+        }
+	pathBuffer[j]=0;
+        if (stat(pathBuffer, &statBuffer) || ! (statBuffer.st_mode & S_IFDIR)) {
+            printf ("Path does not exist or not a directory: %s\n", path);
+            exit (EXIT_FAILURE);
+        }
+    }
+
+    void copyAndChmod(char* path, char* target, mode_t mode) {
+        int pid;
+        pid = fork();
+        if (! pid) {
+            execl("${coreutils}/bin/cp", "cp", path, target, NULL);
+        } else {
+            waitpid (pid, NULL, 0);
+        }
+        chmod (target, mode);
+    }
+    
+    int main () {
+        /* generated code begins */
+EOF
+cat <<EOF >> kill-etc.c
+    #include <sys/types.h>
+    #include <sys/stat.h>
+    #include <unistd.h>
+
+    int main () {
+        /* generated code begins */
+EOF
+
 for ((i = 0; i < ${#targets_[@]}; i++)); do
     ensureDir $out/etc/$(dirname ${targets_[$i]})
     if ! test -e $out/etc/${targets_[$i]}; then
@@ -13,10 +68,29 @@ for ((i = 0; i < ${#targets_[@]}; i++)); do
         echo "Duplicate entry ${targets_[$i]} -> ${sources_[$i]}"
         if test "$(readlink $out/etc/${targets_[$i]})" != "${sources_[$i]}"; then
             echo "Mismatched duplicate entry $(readlink $out/etc/${targets_[$i]}) <-> ${sources_[$i]}"
-	    exit 1
+        exit 1
         fi
     fi;
+    echo "ensureDir(\"/etc/${targets_[$i]}\");" >> fill-etc.c
     if test "${modes_[$i]}" != symlink; then
         echo "${modes_[$i]}" > $out/etc/${targets_[$i]}.mode
+
+        echo "copyAndChmod(\"$out/etc/${targets_[$i]}\",\"/etc/${targets_[$i]}\",${modes_[$i]});" >> fill-etc.c;
+    else
+       echo "symlink(\"$out/etc/${targets_[$i]}\",\"/etc/${targets_[$i]}\");" >> fill-etc.c;
     fi
+
+    echo "unlink (\"/etc/${targets_[$i]}\");" >> kill-etc.c
 done
+
+echo "symlink(\"$out/bin/kill-etc\",\"/etc/kill-etc\");" >> fill-etc.c
+echo "unlink(\"/etc/kill-etc\");" >> kill-etc.c
+echo "  return 0; }" >> fill-etc.c
+echo "  return 0; }" >> kill-etc.c
+ensureDir $out/bin
+ensureDir $out/share/etc-scripts/src
+gcc -Wall fill-etc.c -o $out/bin/fill-etc
+gcc -Wall kill-etc.c -o $out/bin/kill-etc
+cp fill-etc.c $out/share/etc-scripts/src
+cp kill-etc.c $out/share/etc-scripts/src
+