Add a --no-prompt flag to install quietly.

build/install-build-deps.sh

Index: build/install-build-deps.sh
===================================================================
--- build/install-build-deps.sh	(revision 132122)
+++ build/install-build-deps.sh	(working copy)
@@ -24,6 +24,11 @@
   --no-syms)                do_inst_syms=0;;
   --lib32)                  do_inst_lib32=1;;
   --no-lib32)               do_inst_lib32=0;;
+  --bot)                    do_default=1
+                            do_inst_syms=0
+                            do_inst_lib32=0

[cmp, 2012/04/21 19:39:24]

can you remove these previous two lines?  if you leave them, the behavior of
whether --lib32 will be observed changes based on whether it comes before or
after --bot.

when you remove them, it means that this arg is no longer mainly about doing the
right thing 'for a bot', so i would rename this '--no-prompt'

[Peter Mayo, 2012/04/21 21:02:55]

I had not considered passing both "use the right defaults" and "do this" ...
seems incongruous.

Prefer changing it to apply the correct things, except where the commandline
says otherwise.

[cmp, 2012/04/21 21:17:46]

Is there a "right defaults" wrt the lib32+syms flags?  My understanding is that
on some of the bots, we need one set of flags, and on others, we need a
different set/the default.  And on all of them, we need the "no prompt" feature.
 Hmm.

+                            do_quiet=--quiet
+    ;;
   *) usage;;
   esac
   shift
@@ -122,6 +127,9 @@
 # The function will echo the user's selection followed by a newline character.
 # Users can abort the function by pressing CTRL-C. This will call "exit 1".
 yes_no() {
+  if [ 0 -ne "${do_default-0}" ] ; then
+    return $1
+  fi
   local c
   while :; do
     c="$(trap 'stty echo -iuclc icanon 2>/dev/null' EXIT INT TERM QUIT
@@ -180,7 +188,7 @@
 # Intentionally leaving $packages unquoted so it's more readable.
 echo "Packages required: " $packages
 echo
-new_list_cmd="sudo apt-get install --reinstall $(echo $packages)"
+new_list_cmd="sudo apt-get install --reinstall ${do_quiet-} $(echo $packages)"

[cmp, 2012/04/21 19:39:24]

does --quiet imply -y?  assuming no, i think you also want to signal here -y in
the --no-prompt case.

[Peter Mayo, 2012/04/21 21:02:55]

--quiet does not, but $do_quiet was supposed to - fixed there.
-qq does, which was my intent.  Changing 

 if new_list="$(yes n | LANG=C $new_list_cmd)"; then
   # We probably never hit this following line.
   echo "No missing packages, and the packages are up-to-date."
@@ -194,7 +202,7 @@
     echo "No missing packages, and the packages are up-to-date."
   else
     echo "Installing missing packages: $new_list."
-    sudo apt-get install ${new_list}
+    sudo apt-get install ${do_quiet-} ${new_list}

[cmp, 2012/04/21 19:39:24]

does --quiet imply -y?  assuming no, i think you also want to signal here -y in
the --no-prompt case.

[Peter Mayo, 2012/04/21 21:02:55]

as above.

   fi
   echo
 else