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.

If the previous boot failed (defined as failing to get to the end of one
of the normal runlevels), then show the boot menu regardless.

Author: Richard Laager <rlaager@wiktel.com>
Author: Robie Basak <robie.basak@ubuntu.com>
Forwarded: no
Last-Update: 2015-09-04

Patch-Name: quick_boot.patch

diff --git a/configure.ac b/configure.ac
index 596bbe78e05c0b95dd5ffdf5213df1c9bb6649ef..48364fe06390f92557042edf9eb281a57030481d 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -1808,6 +1808,17 @@ 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])

diff --git a/docs/grub.texi b/docs/grub.texi
index 82f6fa4597c99cd318f4be61b722011d3fe7c026..efe9c6e597cd1c76695672e1884a656cc9678ad3 100644 (file)
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -1490,6 +1490,20 @@ This option may be set to a list of GRUB module names separated by spaces.
 Each module will be loaded as early as possible, at the start of
 @file{grub.cfg}.
 
+@item GRUB_RECORDFAIL_TIMEOUT
+If this option is set, it overrides the default recordfail setting.  A
+setting of -1 causes GRUB to wait for user input indefinitely.  However, a
+false positive in the recordfail mechanism may occur if power is lost during
+boot before boot success is recorded in userspace.  The default setting is
+30, which causes GRUB to wait for user input for thirty seconds before
+continuing.  This default allows interactive users the opportunity to switch
+to a different, working kernel, while avoiding a false positive causing the
+boot to block indefinitely on headless and appliance systems where access to
+a console is restricted or limited.
+
+This option is only effective when GRUB was configured with the
+@option{--enable-quick-boot} option.
+
 @end table
 
 The following options are still accepted for compatibility with existing

diff --git a/grub-core/normal/menu.c b/grub-core/normal/menu.c
index 1f3447ad3cacaa3872e9d40388b539b6f1feb28b..906a480a20b68f6278bdd84de99a42995251788d 100644 (file)
--- a/grub-core/normal/menu.c
+++ b/grub-core/normal/menu.c
@@ -604,6 +604,30 @@ run_menu (grub_menu_t menu, int nested, int *auto_boot)
       static struct grub_term_coordinate *pos;
       int entry = -1;
 
+      if (timeout == 0)
+       {
+         /* If modifier key statuses can't be detected without a delay,
+            then a hidden timeout of zero cannot be interrupted in any way,
+            which is not very helpful.  Bump it to three seconds in this
+            case to give the user a fighting chance.  */
+         grub_term_input_t term;
+         int nterms = 0;
+         int mods_detectable = 1;
+
+         FOR_ACTIVE_TERM_INPUTS(term)
+         {
+           if (!term->getkeystatus)
+             {
+               mods_detectable = 0;
+               break;
+             }
+           else
+             nterms++;
+         }
+         if (!mods_detectable || !nterms)
+           timeout = 3;
+       }
+
       if (timeout_style == TIMEOUT_STYLE_COUNTDOWN && timeout)
        {
          pos = grub_term_save_pos ();

diff --git a/util/grub-mkconfig.in b/util/grub-mkconfig.in
index c05f0d1f30595a71863dda7ef28e592a62e88533..2dc9aa8b8b5e1554bfd6ad04f5e96965dc595117 100644 (file)
--- a/util/grub-mkconfig.in
+++ b/util/grub-mkconfig.in
@@ -239,7 +239,8 @@ export GRUB_DEFAULT \
   GRUB_ENABLE_CRYPTODISK \
   GRUB_BADRAM \
   GRUB_OS_PROBER_SKIP_LIST \
-  GRUB_DISABLE_SUBMENU
+  GRUB_DISABLE_SUBMENU \
+  GRUB_RECORDFAIL_TIMEOUT
 
 if test "x${grub_cfg}" != "x"; then
   rm -f "${grub_cfg}.new"

diff --git a/util/grub.d/00_header.in b/util/grub.d/00_header.in
index 93a90233ead40bfbb9d0994ae41098aa884a36d7..674a76140202f21033ddd95f31fafc47171a79c7 100644 (file)
--- a/util/grub.d/00_header.in
+++ b/util/grub.d/00_header.in
@@ -21,6 +21,8 @@ prefix="@prefix@"
 exec_prefix="@exec_prefix@"
 datarootdir="@datarootdir@"
 grub_lang=`echo $LANG | cut -d . -f 1`
+grubdir="`echo "/@bootdirname@/@grubdirname@" | sed 's,//*,/,g'`"
+quick_boot="@QUICK_BOOT@"
 
 export TEXTDOMAIN=@PACKAGE@
 export TEXTDOMAINDIR="@localedir@"
@@ -44,6 +46,7 @@ if [ "x${GRUB_TIMEOUT_BUTTON}" = "x" ] ; then GRUB_TIMEOUT_BUTTON="$GRUB_TIMEOUT
 
 cat << EOF
 if [ -s \$prefix/grubenv ]; then
+  set have_grubenv=true
   load_env
 fi
 EOF
@@ -96,7 +99,50 @@ function savedefault {
     save_env saved_entry
   fi
 }
+EOF
+
+if [ "$quick_boot" = 1 ]; then
+    cat <<EOF
+function recordfail {
+  set recordfail=1
+EOF
+
+  check_writable () {
+    abstractions="$(grub-probe --target=abstraction "${grubdir}")"
+    for abstraction in $abstractions; do
+      case "$abstraction" in
+        diskfilter | lvm)
+          cat <<EOF
+  # GRUB lacks write support for $abstraction, so recordfail support is disabled.
+EOF
+          return
+          ;;
+      esac
+    done
+
+    FS="$(grub-probe --target=fs "${grubdir}")"
+    case "$FS" in
+      btrfs | cpiofs | newc | odc | romfs | squash4 | tarfs | zfs)
+       cat <<EOF
+  # GRUB lacks write support for $FS, so recordfail support is disabled.
+EOF
+       return
+       ;;
+    esac
+
+    cat <<EOF
+  if [ -n "\${have_grubenv}" ]; then if [ -z "\${boot_once}" ]; then save_env recordfail; fi; fi
+EOF
+  }
+
+  check_writable
 
+  cat <<EOF
+}
+EOF
+fi
+
+cat <<EOF
 function load_video {
 EOF
 if [ -n "${GRUB_VIDEO_BACKEND}" ]; then
@@ -282,10 +328,16 @@ fi
 
 make_timeout ()
 {
+    cat << EOF
+if [ "\${recordfail}" = 1 ] ; then
+  set timeout=${GRUB_RECORDFAIL_TIMEOUT:-30}
+else
+EOF
     if [ "x${3}" != "x" ] ; then
        timeout="${2}"
        style="${3}"
-    elif [ "x${1}" != "x" ] && [ "x${1}" != "x0" ] ; then
+    elif [ "x${1}" != "x" ] && \
+        ([ "$quick_boot" = 1 ] || [ "x${1}" != "x0" ]) ; then
        # Handle the deprecated GRUB_HIDDEN_TIMEOUT scheme.
        timeout="${1}"
        if [ "x${2}" != "x0" ] ; then
@@ -304,26 +356,27 @@ make_timeout ()
        style="menu"
     fi
     cat << EOF
-if [ x\$feature_timeout_style = xy ] ; then
-  set timeout_style=${style}
-  set timeout=${timeout}
+  if [ x\$feature_timeout_style = xy ] ; then
+    set timeout_style=${style}
+    set timeout=${timeout}
 EOF
     if [ "x${style}" = "xmenu" ] ; then
        cat << EOF
-# Fallback normal timeout code in case the timeout_style feature is
-# unavailable.
-else
-  set timeout=${timeout}
+  # Fallback normal timeout code in case the timeout_style feature is
+  # unavailable.
+  else
+    set timeout=${timeout}
 EOF
     else
        cat << EOF
-# Fallback hidden-timeout code in case the timeout_style feature is
-# unavailable.
-elif sleep${verbose} --interruptible ${timeout} ; then
-  set timeout=0
+  # Fallback hidden-timeout code in case the timeout_style feature is
+  # unavailable.
+  elif sleep${verbose} --interruptible ${timeout} ; then
+    set timeout=0
 EOF
     fi
     cat << EOF
+  fi
 fi
 EOF
 }

diff --git a/util/grub.d/10_linux.in b/util/grub.d/10_linux.in
index d203c37a66a044104114332284e2d5eefcdb4374..b32cc53b0583c02364c9f6997ff936023818eee4 100644 (file)
--- a/util/grub.d/10_linux.in
+++ b/util/grub.d/10_linux.in
@@ -22,6 +22,7 @@ exec_prefix="@exec_prefix@"
 datarootdir="@datarootdir@"
 ubuntu_recovery="@UBUNTU_RECOVERY@"
 quiet_boot="@QUIET_BOOT@"
+quick_boot="@QUICK_BOOT@"
 
 . "$pkgdatadir/grub-mkconfig_lib"
 
@@ -119,6 +120,9 @@ linux_entry ()
   else
       echo "menuentry '$(echo "$os" | grub_quote)' ${CLASS} \$menuentry_id_option 'gnulinux-simple-$boot_device_id' {" | sed "s/^/$submenu_indentation/"
   fi      
+  if [ "$quick_boot" = 1 ]; then
+      echo "   recordfail" | sed "s/^/$submenu_indentation/"
+  fi
   if [ x$type != xrecovery ] ; then
       save_default_entry | grub_add_tab
   fi

diff --git a/util/grub.d/30_os-prober.in b/util/grub.d/30_os-prober.in
index 271044f5925a46c986447d508d4cbd4f2591ac0f..da5f28876de7bd7c29eaafa88e733e13a6e486c4 100644 (file)
--- a/util/grub.d/30_os-prober.in
+++ b/util/grub.d/30_os-prober.in
@@ -20,12 +20,26 @@ set -e
 prefix="@prefix@"
 exec_prefix="@exec_prefix@"
 datarootdir="@datarootdir@"
+quick_boot="@QUICK_BOOT@"
 
 export TEXTDOMAIN=@PACKAGE@
 export TEXTDOMAINDIR="@localedir@"
 
 . "$pkgdatadir/grub-mkconfig_lib"
 
+found_other_os=
+
+adjust_timeout () {
+  if [ "$quick_boot" = 1 ] && [ "x${found_other_os}" != "x" ]; then
+    cat << EOF
+set timeout_style=menu
+if [ "\${timeout}" = 0 ]; then
+  set timeout=10
+fi
+EOF
+  fi
+}
+
 if [ "x${GRUB_DISABLE_OS_PROBER}" = "xtrue" ]; then
   exit 0
 fi
@@ -42,6 +56,7 @@ if [ -z "${OSPROBED}" ] ; then
 fi
 
 osx_entry() {
+    found_other_os=1
     if [ x$2 = x32 ]; then
         # TRANSLATORS: it refers to kernel architecture (32-bit)
        bitstr="$(gettext "(32-bit)")"
@@ -165,6 +180,7 @@ for OS in ${OSPROBED} ; do
          ;;
       esac
 
+      found_other_os=1
          onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
       cat << EOF
 menuentry '$(echo "${LONGNAME} $onstr" | grub_quote)' $CLASS --class os \$menuentry_id_option 'osprober-chain-$(grub_get_device_id "${DEVICE}")' {
@@ -195,6 +211,7 @@ EOF
     ;;
     efi)
 
+       found_other_os=1
        EFIPATH=${DEVICE#*@}
        DEVICE=${DEVICE%@*}
        onstr="$(gettext_printf "(on %s)" "${DEVICE}")"
@@ -243,6 +260,7 @@ 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
@@ -311,6 +329,7 @@ EOF
       fi
     ;;
     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}")' {
@@ -353,3 +372,5 @@ EOF
     ;;
   esac
 done
+
+adjust_timeout