Added restart_in_chroot_if_needed to common.sh.

Add restart_in_chroot_if_needed to common.sh, and modify the build scripts which referred to assert_inside_chroot to use it instead. The effect is that you don't ever have to explicitly enter_chroot.sh to build (still can, it work's fine).

Update mod_image_for_test.sh to use restart_in_chroot_if_needed

Review URL: http://codereview.chromium.org/1736025

build_gpt.sh

@@ -12,7 +12,7 @@
 . "$(dirname "$0")/chromeos-common.sh"
 
 # Script must be run inside the chroot.
-assert_inside_chroot
+restart_in_chroot_if_needed $*
 
 get_default_board
 

build_image

@@ -14,7 +14,7 @@
 . "$(dirname "$0")/common.sh"
 
 # Script must be run inside the chroot.
-assert_inside_chroot
+restart_in_chroot_if_needed $*
 
 get_default_board
 

build_tests.sh

@@ -8,8 +8,8 @@
 # The path to common.sh should be relative to your script's location.
 . "$(dirname "$0")/common.sh"
 
-assert_inside_chroot
 assert_not_root_user
+restart_in_chroot_if_needed $*
 get_default_board
 
 # Flags

common.sh

@@ -207,6 +207,16 @@ function make_pkg_common {
   popd
 }
 
+# Enter a chroot and restart the current script if needed
+function restart_in_chroot_if_needed {
+  if [ $INSIDE_CHROOT -ne 1 ]
+  then
+    # Equivalent to enter_chroot.sh -- <current command>
+    exec $SCRIPTS_DIR/enter_chroot.sh -- \
+      $CHROOT_TRUNK_DIR/src/scripts/$(basename $0) $*
+  fi
+}
+
 # Fail unless we're inside the chroot.  This guards against messing up your
 # workstation.
 function assert_inside_chroot {

run_tests.sh

@@ -9,7 +9,7 @@
 . "$(dirname "$0")/common.sh"
 
 # Script must be run inside the chroot
-assert_inside_chroot
+restart_in_chroot_if_needed $*
 get_default_board
 
 # Flags

set_shared_user_password.sh

@@ -12,7 +12,7 @@
 . "$(dirname "$0")/common.sh"
 
 # Script must be run inside the chroot
-assert_inside_chroot
+restart_in_chroot_if_needed $*
 
 FLAGS_HELP="USAGE: $0 [flags]"
 

start_devserver

@@ -10,6 +10,9 @@ COMMON_SH="$(dirname "$0")/common.sh"
 . "$COMMON_SH"
 
 # Script must be run inside the chroot if not in 'always serve' mode.
-[[ $1 != "-a" && assert_inside_chroot ]]
+if [[ "$1" != "-a" ]]
+then
+  restart_in_chroot_if_needed $*
+fi
 
 cd ${GCLIENT_ROOT}/src/platform/dev && python devserver.py $*