If building for Ubuntu, bypass menu unless other OSes are installed or Shift is pressed.

configure.ac

@@ -1087,6 +1087,17 @@ else
 fi
 AC_SUBST([QUIET_BOOT])
 
+AC_ARG_ENABLE([quick-boot],
+              [AS_HELP_STRING([--enable-quick-boot],
+                              [bypass boot menu if possible (default=no)])],
+              [], [enable_quick_boot=no])
+if test x"$enable_quick_boot" = xyes ; then
+  QUICK_BOOT=1
+else
+  QUICK_BOOT=0
+fi
+AC_SUBST([QUICK_BOOT])
+
 LIBS=""
 
 AC_SUBST([FONT_SOURCE])

debian/changelog

@@ -15,6 +15,8 @@ grub2 (2.00-20) UNRELEASED; urgency=low
       partition for use (Steve Langasek).
     - Adjust UEFI installation to cope with Kubuntu setting GRUB_DISTRIBUTOR
       (LP: #1242417).
+    - If building for Ubuntu:
+      + Bypass menu unless other OSes are installed or Shift is pressed.
 
  -- Colin Watson <cjwatson@debian.org>  Mon, 07 Oct 2013 09:48:53 +0100
 

debian/patches/quick_boot.patch

@@ -0,0 +1,191 @@
+Description: Add configure option to bypass boot menu if possible
+ If other operating systems are installed, then automatically unhide the
+ menu.  Otherwise, if GRUB_HIDDEN_TIMEOUT is 0, then use keystatus if
+ available to check whether Shift is pressed.  If it is, show the menu,
+ otherwise boot immediately.  If keystatus is not available, then fall back
+ to a short delay interruptible with Escape.
+ .
+ This may or may not remain Ubuntu-specific, although it's not obviously
+ wanted upstream.  It implements a requirement of
+ https://wiki.ubuntu.com/DesktopExperienceTeam/KarmicBootExperienceDesignSpec#Bootloader.
+Author: Colin Watson <cjwatson@ubuntu.com>
+Forwarded: no
+Last-Update: 2013-11-12
+
+Index: b/configure.ac
+===================================================================
+--- a/configure.ac
++++ b/configure.ac
+@@ -1087,6 +1087,17 @@
+ fi
+ AC_SUBST([QUIET_BOOT])
+ 
++AC_ARG_ENABLE([quick-boot],
++              [AS_HELP_STRING([--enable-quick-boot],
++                              [bypass boot menu if possible (default=no)])],
++              [], [enable_quick_boot=no])
++if test x"$enable_quick_boot" = xyes ; then
++  QUICK_BOOT=1
++else
++  QUICK_BOOT=0
++fi
++AC_SUBST([QUICK_BOOT])
++
+ LIBS=""
+ 
+ AC_SUBST([FONT_SOURCE])
+Index: b/util/grub.d/00_header.in
+===================================================================
+--- a/util/grub.d/00_header.in
++++ b/util/grub.d/00_header.in
+@@ -23,6 +23,7 @@
+ exec_prefix="@exec_prefix@"
+ datarootdir="@datarootdir@"
+ grub_lang=`echo $LANG | cut -d . -f 1`
++quick_boot="@QUICK_BOOT@"
+ 
+ export TEXTDOMAIN=@PACKAGE@
+ export TEXTDOMAINDIR="@localedir@"
+@@ -272,7 +273,7 @@
+ 
+ make_timeout ()
+ {
+-    if [ "x${1}" != "x" ] ; then
++    if [ "$quick_boot" = 0 ] && [ "x${1}" != "x" ] ; then
+ 	if [ "x${GRUB_HIDDEN_TIMEOUT_QUIET}" = "xtrue" ] ; then
+ 	    verbose=
+ 	else
+Index: b/util/grub.d/30_os-prober.in
+===================================================================
+--- a/util/grub.d/30_os-prober.in
++++ b/util/grub.d/30_os-prober.in
+@@ -20,18 +20,78 @@
+ prefix="@prefix@"
+ exec_prefix="@exec_prefix@"
+ datarootdir="@datarootdir@"
++quick_boot="@QUICK_BOOT@"
+ 
+ export TEXTDOMAIN=@PACKAGE@
+ export TEXTDOMAINDIR="@localedir@"
+ 
+ . "@datadir@/@PACKAGE@/grub-mkconfig_lib"
+ 
++found_other_os=
++
++make_timeout () {
++  if [ "x${found_other_os}" = "x" ] ; then
++    if [ "x${1}" != "x" ] ; then
++      if [ "x${GRUB_HIDDEN_TIMEOUT_QUIET}" = "xtrue" ] ; then
++	verbose=
++      else
++	verbose=" --verbose"
++      fi
++
++      if [ "x${1}" = "x0" ] ; then
++	cat <<EOF
++if [ "x\${timeout}" != "x-1" ]; then
++  if keystatus; then
++    if keystatus --shift; then
++      set timeout=-1
++    else
++      set timeout=0
++    fi
++  else
++    if sleep$verbose --interruptible 3 ; then
++      set timeout=0
++    fi
++  fi
++fi
++EOF
++      else
++	cat << EOF
++if [ "x\${timeout}" != "x-1" ]; then
++  if sleep$verbose --interruptible ${GRUB_HIDDEN_TIMEOUT} ; then
++    set timeout=0
++  fi
++fi
++EOF
++      fi
++    fi
++  fi
++}
++
++adjust_timeout () {
++  if [ "$quick_boot" = 0 ]; then
++    return
++  fi
++  if [ "x$GRUB_BUTTON_CMOS_ADDRESS" != "x" ]; then
++    cat <<EOF
++if cmostest $GRUB_BUTTON_CMOS_ADDRESS ; then
++EOF
++    make_timeout "${GRUB_HIDDEN_TIMEOUT_BUTTON}" "${GRUB_TIMEOUT_BUTTON}"
++    echo else
++    make_timeout "${GRUB_HIDDEN_TIMEOUT}" "${GRUB_TIMEOUT}"
++    echo fi
++  else
++    make_timeout "${GRUB_HIDDEN_TIMEOUT}" "${GRUB_TIMEOUT}"
++  fi
++}
++
+ if [ "x${GRUB_DISABLE_OS_PROBER}" = "xtrue" ]; then
++  adjust_timeout
+   exit 0
+ fi
+ 
+ if [ -z "`which os-prober 2> /dev/null`" -o -z "`which linux-boot-prober 2> /dev/null`" ] ; then
+   # missing os-prober and/or linux-boot-prober
++  adjust_timeout
+   exit 0
+ fi
+ 
+@@ -43,10 +103,12 @@
+ OSPROBED="`os-prober | tr ' ' '^' | paste -s -d ' '`"
+ if [ -z "${OSPROBED}" ] ; then
+   # empty os-prober output, nothing doing
++  adjust_timeout
+   exit 0
+ fi
+ 
+ osx_entry() {
++    found_other_os=1
+     if [ x$2 = x32 ]; then
+         # TRANSLATORS: it refers to kernel architecture (32-bit)
+ 	bitstr="$(gettext "(32-bit)")"
+@@ -146,6 +208,7 @@
+ 	  ;;
+       esac
+ 
++      found_other_os=1
+ 	  onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
+       cat << EOF
+ menuentry '$(echo "${LONGNAME} $onstr" | grub_quote)' --class windows --class os \$menuentry_id_option 'osprober-chain-$(grub_get_device_id "${DEVICE}")' {
+@@ -169,6 +232,7 @@
+ EOF
+     ;;
+     efi)
++      found_other_os=1
+       EFIPATH=${DEVICE#*@}
+       DEVICE=${DEVICE%@*}
+       cat << EOF
+@@ -211,6 +275,7 @@
+ 	  [ "${prepare_boot_cache}" ] || continue
+ 	fi
+ 
++	found_other_os=1
+ 	onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
+ 	recovery_params="$(echo "${LPARAMS}" | grep 'single\|recovery')" || true
+ 	counter=1
+@@ -277,6 +342,7 @@
+       osx_entry xnu_kernel64 64
+     ;;
+     hurd)
++      found_other_os=1
+       onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
+       cat << EOF
+ menuentry '$(echo "${LONGNAME} $onstr" | grub_quote)' --class hurd --class gnu --class os \$menuentry_id_option 'osprober-gnuhurd-/boot/gnumach.gz-false-$(grub_get_device_id "${DEVICE}")' {
+@@ -309,3 +375,5 @@
+     ;;
+   esac
+ done
++
++adjust_timeout

debian/patches/series

@@ -57,3 +57,4 @@ efidisk_non_512_sectors.patch
 mkconfig_hurd_sort.patch
 probe_dmraid.patch
 install_efi_ubuntu_flavours.patch
+quick_boot.patch

debian/rules

@@ -54,7 +54,7 @@ endif
 
 ifeq (yes,$(shell dpkg-vendor --derives-from Ubuntu && echo yes))
 DEFAULT_CMDLINE := quiet splash
-confflags += --enable-quiet-boot
+confflags += --enable-quiet-boot --enable-quick-boot
 else
 DEFAULT_CMDLINE := quiet
 endif

util/grub.d/00_header.in

@@ -23,6 +23,7 @@ prefix="@prefix@"
 exec_prefix="@exec_prefix@"
 datarootdir="@datarootdir@"
 grub_lang=`echo $LANG | cut -d . -f 1`
+quick_boot="@QUICK_BOOT@"
 
 export TEXTDOMAIN=@PACKAGE@
 export TEXTDOMAINDIR="@localedir@"
@@ -272,7 +273,7 @@ fi
 
 make_timeout ()
 {
-    if [ "x${1}" != "x" ] ; then
+    if [ "$quick_boot" = 0 ] && [ "x${1}" != "x" ] ; then
 	if [ "x${GRUB_HIDDEN_TIMEOUT_QUIET}" = "xtrue" ] ; then
 	    verbose=
 	else

util/grub.d/30_os-prober.in

@@ -20,18 +20,78 @@ set -e
 prefix="@prefix@"
 exec_prefix="@exec_prefix@"
 datarootdir="@datarootdir@"
+quick_boot="@QUICK_BOOT@"
 
 export TEXTDOMAIN=@PACKAGE@
 export TEXTDOMAINDIR="@localedir@"
 
 . "@datadir@/@PACKAGE@/grub-mkconfig_lib"
 
+found_other_os=
+
+make_timeout () {
+  if [ "x${found_other_os}" = "x" ] ; then
+    if [ "x${1}" != "x" ] ; then
+      if [ "x${GRUB_HIDDEN_TIMEOUT_QUIET}" = "xtrue" ] ; then
+	verbose=
+      else
+	verbose=" --verbose"
+      fi
+
+      if [ "x${1}" = "x0" ] ; then
+	cat <<EOF
+if [ "x\${timeout}" != "x-1" ]; then
+  if keystatus; then
+    if keystatus --shift; then
+      set timeout=-1
+    else
+      set timeout=0
+    fi
+  else
+    if sleep$verbose --interruptible 3 ; then
+      set timeout=0
+    fi
+  fi
+fi
+EOF
+      else
+	cat << EOF
+if [ "x\${timeout}" != "x-1" ]; then
+  if sleep$verbose --interruptible ${GRUB_HIDDEN_TIMEOUT} ; then
+    set timeout=0
+  fi
+fi
+EOF
+      fi
+    fi
+  fi
+}
+
+adjust_timeout () {
+  if [ "$quick_boot" = 0 ]; then
+    return
+  fi
+  if [ "x$GRUB_BUTTON_CMOS_ADDRESS" != "x" ]; then
+    cat <<EOF
+if cmostest $GRUB_BUTTON_CMOS_ADDRESS ; then
+EOF
+    make_timeout "${GRUB_HIDDEN_TIMEOUT_BUTTON}" "${GRUB_TIMEOUT_BUTTON}"
+    echo else
+    make_timeout "${GRUB_HIDDEN_TIMEOUT}" "${GRUB_TIMEOUT}"
+    echo fi
+  else
+    make_timeout "${GRUB_HIDDEN_TIMEOUT}" "${GRUB_TIMEOUT}"
+  fi
+}
+
 if [ "x${GRUB_DISABLE_OS_PROBER}" = "xtrue" ]; then
+  adjust_timeout
   exit 0
 fi
 
 if [ -z "`which os-prober 2> /dev/null`" -o -z "`which linux-boot-prober 2> /dev/null`" ] ; then
   # missing os-prober and/or linux-boot-prober
+  adjust_timeout
   exit 0
 fi
 
@@ -43,10 +103,12 @@ modprobe efivars >/dev/null 2>&1 || true
 OSPROBED="`os-prober | tr ' ' '^' | paste -s -d ' '`"
 if [ -z "${OSPROBED}" ] ; then
   # empty os-prober output, nothing doing
+  adjust_timeout
   exit 0
 fi
 
 osx_entry() {
+    found_other_os=1
     if [ x$2 = x32 ]; then
         # TRANSLATORS: it refers to kernel architecture (32-bit)
 	bitstr="$(gettext "(32-bit)")"
@@ -146,6 +208,7 @@ for OS in ${OSPROBED} ; do
 	  ;;
       esac
 
+      found_other_os=1
 	  onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
       cat << EOF
 menuentry '$(echo "${LONGNAME} $onstr" | grub_quote)' --class windows --class os \$menuentry_id_option 'osprober-chain-$(grub_get_device_id "${DEVICE}")' {
@@ -169,6 +232,7 @@ EOF
 EOF
     ;;
     efi)
+      found_other_os=1
       EFIPATH=${DEVICE#*@}
       DEVICE=${DEVICE%@*}
       cat << EOF
@@ -211,6 +275,7 @@ EOF
 	  [ "${prepare_boot_cache}" ] || continue
 	fi
 
+	found_other_os=1
 	onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
 	recovery_params="$(echo "${LPARAMS}" | grep 'single\|recovery')" || true
 	counter=1
@@ -277,6 +342,7 @@ EOF
       osx_entry xnu_kernel64 64
     ;;
     hurd)
+      found_other_os=1
       onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
       cat << EOF
 menuentry '$(echo "${LONGNAME} $onstr" | grub_quote)' --class hurd --class gnu --class os \$menuentry_id_option 'osprober-gnuhurd-/boot/gnumach.gz-false-$(grub_get_device_id "${DEVICE}")' {
@@ -309,3 +375,5 @@ EOF
     ;;
   esac
 done
+
+adjust_timeout