nixos: iso-image: use syslinux bootloader for USB booting support

nixos/lib/make-iso9660-image.nix

@@ -1,4 +1,4 @@
-{ stdenv, perl, cdrkit, pathsFromGraph
+{ stdenv, perl, pathsFromGraph, xorriso, syslinux
 
 , # The file name of the resulting ISO image.
   isoName ? "cd.iso"
@@ -22,12 +22,18 @@
 , # Whether this should be an efi-bootable El-Torito CD.
   efiBootable ? false
 
+, # Wheter this should be an hybrid CD (bootable from USB as well as CD).
+  usbBootable ? false
+
 , # The path (in the ISO file system) of the boot image.
   bootImage ? ""
 
 , # The path (in the ISO file system) of the efi boot image.
   efiBootImage ? ""
 
+, # The path (outside the ISO file system) of the isohybrid-mbr image.
+  isohybridMbrImage ? ""
+
 , # Whether to compress the resulting ISO image with bzip2.
   compressImage ? false
 
@@ -38,13 +44,14 @@
 
 assert bootable -> bootImage != "";
 assert efiBootable -> efiBootImage != "";
+assert usbBootable -> isohybridMbrImage != "";
 
 stdenv.mkDerivation {
   name = "iso9660-image";
   builder = ./make-iso9660-image.sh;
-  buildInputs = [perl cdrkit];
+  buildInputs = [perl xorriso syslinux];
 
-  inherit isoName bootable bootImage compressImage volumeID pathsFromGraph efiBootImage efiBootable;
+  inherit isoName bootable bootImage compressImage volumeID pathsFromGraph efiBootImage efiBootable isohybridMbrImage usbBootable;
 
   # !!! should use XML.
   sources = map (x: x.source) contents;

nixos/lib/make-iso9660-image.sh

@@ -13,6 +13,20 @@ stripSlash() {
     if test "${res:0:1}" = /; then res=${res:1}; fi
 }
 
+# Escape potential equal signs (=) with backslash (\=)
+escapeEquals() {
+    echo "$1" | sed -e 's/\\/\\\\/g' -e 's/=/\\=/g'
+}
+
+# Queues an file/directory to be placed on the ISO.
+# An entry consists of a local source path (2) and
+# a destination path on the ISO (1).
+addPath() {
+    target="$1"
+    source="$2"
+    echo "$(escapeEquals "$target")=$(escapeEquals "$source")" >> pathlist
+}
+
 stripSlash "$bootImage"; bootImage="$res"
 
 
@@ -31,11 +45,20 @@ if test -n "$bootable"; then
         fi
     done
 
-    bootFlags="-b $bootImage -c .boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table"
+    isoBootFlags="-eltorito-boot ${bootImage}
+                  -eltorito-catalog .boot.cat
+                  -no-emul-boot -boot-load-size 4 -boot-info-table"
+fi
+
+if test -n "$usbBootable"; then
+    usbBootFlags="-isohybrid-mbr ${isohybridMbrImage}"
 fi
 
 if test -n "$efiBootable"; then
-    bootFlags="$bootFlags -eltorito-alt-boot -e $efiBootImage -no-emul-boot"
+    efiBootFlags="-eltorito-alt-boot
+                  -e $efiBootImage
+                  -no-emul-boot
+                  -isohybrid-gpt-basdat"
 fi
 
 touch pathlist
@@ -44,22 +67,22 @@ touch pathlist
 # Add the individual files.
 for ((i = 0; i < ${#targets_[@]}; i++)); do
     stripSlash "${targets_[$i]}"
-    echo "$res=${sources_[$i]}" >> pathlist
+    addPath "$res" "${sources_[$i]}"
 done
 
 
 # Add the closures of the top-level store objects.
 storePaths=$(perl $pathsFromGraph closure-*)
 for i in $storePaths; do
-    echo "${i:1}=$i" >> pathlist
+    addPath "${i:1}" "$i"
 done
 
 
 # Also include a manifest of the closures in a format suitable for
 # nix-store --load-db.
 if [ -n "$object" ]; then
     printRegistration=1 perl $pathsFromGraph closure-* > nix-path-registration
-    echo "nix-path-registration=nix-path-registration" >> pathlist
+    addPath "nix-path-registration" "nix-path-registration"
 fi
 
 
@@ -70,22 +93,39 @@ for ((n = 0; n < ${#objects[*]}; n++)); do
     if test "$symlink" != "none"; then
         mkdir -p $(dirname ./$symlink)
         ln -s $object ./$symlink
-        echo "$symlink=./$symlink" >> pathlist
+        addPath "$symlink" "./$symlink"
     fi
 done
 
-# !!! what does this do?
-cat pathlist | sed -e 's/=\(.*\)=\(.*\)=/\\=\1=\2\\=/' | tee pathlist.safer
-
-
 mkdir -p $out/iso
-genCommand="genisoimage -iso-level 4 -r -J $bootFlags -hide-rr-moved -graft-points -path-list pathlist.safer ${volumeID:+-V $volumeID}"
-if test -z "$compressImage"; then
-    $genCommand -o $out/iso/$isoName
-else
-    $genCommand | bzip2 > $out/iso/$isoName.bz2
+
+xorriso="xorriso
+ -as mkisofs
+ -iso-level 3
+ -volid ${volumeID}
+ -appid nixos
+ -publisher nixos
+ -graft-points
+ -full-iso9660-filenames
+ ${isoBootFlags}
+ ${usbBootFlags}
+ ${efiBootFlags}
+ -r
+ -path-list pathlist
+ --sort-weight 0 /
+ --sort-weight 1 /isolinux" # Make sure isolinux is near the beginning of the ISO
+
+$xorriso -output $out/iso/$isoName
+
+if test -n "$usbBootable"; then
+    echo "Making image hybrid..."
+    isohybrid --uefi $out/iso/$isoName
 fi
 
+if test -n "$compressImage"; then
+    echo "Compressing image..."
+    bzip2 $out/iso/$isoName
+fi
 
 mkdir -p $out/nix-support
 echo $system > $out/nix-support/system

nixos/lib/test-driver/Machine.pm

@@ -37,6 +37,10 @@ sub new {
             if defined $args->{hda};
         $startCommand .= "-cdrom $args->{cdrom} "
             if defined $args->{cdrom};
+        $startCommand .= "-device piix3-usb-uhci -drive id=usbdisk,file=$args->{usb},if=none,readonly -device usb-storage,drive=usbdisk "
+            if defined $args->{usb};
+        $startCommand .= "-bios $args->{bios} "
+            if defined $args->{bios};
         $startCommand .= $args->{qemuFlags} || "";
     } else {
         $startCommand = Cwd::abs_path $startCommand;

nixos/modules/installer/cd-dvd/installation-cd-base.nix

@@ -36,6 +36,9 @@ with lib;
   # EFI booting
   isoImage.makeEfiBootable = true;
 
+  # USB booting
+  isoImage.makeUsbBootable = true;
+
   # Add Memtest86+ to the CD.
   boot.loader.grub.memtest86.enable = true;