*: add --usepkgonly flag to avoid building from source

build_packages

@@ -16,6 +16,8 @@ DEFINE_string board "${DEFAULT_BOARD}" \
   "The board to build packages for."
 DEFINE_boolean usepkg "${FLAGS_TRUE}" \
   "Use binary packages when possible."
+DEFINE_boolean usepkgonly "${FLAGS_FALSE}" \
+  "Only use/download binary packages. Implies --noworkon"
 DEFINE_boolean getbinpkg "${FLAGS_TRUE}" \
   "Download binary packages from remote repository."
 DEFINE_string getbinpkgver "" \
@@ -67,6 +69,19 @@ if [[ -z "${FLAGS_board}" ]]; then
   exit 1
 fi
 
+if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+  for flag in usepkg getbinpkg; do
+    fvar="FLAGS_${flag}"
+    if [[ "${!fvar}" -ne "${FLAGS_TRUE}" ]]; then
+      die_notrace "--usepkgonly is incompatible with --no${flag}"
+    fi
+  done
+  if [[ "${FLAGS_rebuild}" -eq "${FLAGS_TRUE}" ]]; then
+    die_notrace "--usepkgonly is incompatible with --rebuild"
+  fi
+  FLAGS_workon="${FLAGS_FALSE}"
+fi
+
 check_gsutil_opts
 
 CHROMITE_BIN="${GCLIENT_ROOT}/chromite/bin"
@@ -75,6 +90,11 @@ CHROMITE_BIN="${GCLIENT_ROOT}/chromite/bin"
 UPDATE_ARGS=( --regen_configs )
 if [ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}" ]; then
   UPDATE_ARGS+=( --usepkg )
+  if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+    UPDATE_ARGS+=( --usepkgonly )
+  else
+    UPDATE_ARGS+=( --nousepkgonly )
+  fi
   if [[ "${FLAGS_getbinpkg}" -eq "${FLAGS_TRUE}" ]]; then
     UPDATE_ARGS+=( --getbinpkg )
   else
@@ -121,15 +141,19 @@ EMERGE_CMD+=( ${EXTRA_BOARD_FLAGS} )
 if [[ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}" ]]; then
   # Use binary packages. Include all build-time dependencies,
   # so as to avoid unnecessary differences between source
-  # and binary builds.
+  # and binary builds except for --usepkgonly for speed.
-  EMERGE_FLAGS+=( --usepkg --with-bdeps y )
+  if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+    EMERGE_FLAGS+=( --usepkgonly )
+  else
+    EMERGE_FLAGS+=( --usepkg --with-bdeps y )
+
+    # Only update toolchain when binpkgs are available.
+    EMERGE_FLAGS+=( $(get_binonly_args) )
+    REBUILD_FLAGS+=( $(get_binonly_args) )
+  fi
   if [[ "${FLAGS_getbinpkg}" -eq "${FLAGS_TRUE}" ]]; then
       EMERGE_FLAGS+=( --getbinpkg )
   fi
-
-  # Only update toolchain when binpkgs are available.
-  EMERGE_FLAGS+=( $(get_binonly_args) )
-  REBUILD_FLAGS+=( $(get_binonly_args) )
 fi
 
 if [[ "${FLAGS_jobs}" -ne -1 ]]; then
@@ -199,11 +223,13 @@ break_dep_loop() {
   sudo rm -f "${flag_file}"
 }
 
-# util-linux[udev] -> virtual->udev -> systemd -> util-linux
+if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_FALSE}" ]]; then
-break_dep_loop sys-apps/util-linux udev,systemd sys-apps/systemd cryptsetup
+  # util-linux[udev] -> virtual->udev -> systemd -> util-linux
+  break_dep_loop sys-apps/util-linux udev,systemd sys-apps/systemd cryptsetup
 
-# systemd[cryptsetup] -> cryptsetup -> lvm2 -> virtual/udev -> systemd
+  # systemd[cryptsetup] -> cryptsetup -> lvm2 -> virtual/udev -> systemd
-break_dep_loop sys-apps/systemd cryptsetup
+  break_dep_loop sys-apps/systemd cryptsetup
+fi
 
 info "Merging board packages now"
 sudo -E "${EMERGE_CMD[@]}" "${EMERGE_FLAGS[@]}" "$@"
@@ -211,8 +237,10 @@ sudo -E "${EMERGE_CMD[@]}" "${EMERGE_FLAGS[@]}" "$@"
 info "Removing obsolete packages"
 sudo -E "${EMERGE_CMD[@]}" --quiet --depclean @unavailable
 
-if "portageq-${BOARD}" list_preserved_libs "${BOARD_ROOT}" >/dev/null; then
+if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
-  sudo -E "${EMERGE_CMD[@]}" "${REBUILD_FLAGS[@]}" @preserved-rebuild
+  if "portageq-${BOARD}" list_preserved_libs "${BOARD_ROOT}" >/dev/null; then
+    sudo -E "${EMERGE_CMD[@]}" "${REBUILD_FLAGS[@]}" @preserved-rebuild
+  fi
 fi
 
 info "Checking build root"

setup_board

@@ -21,6 +21,8 @@ DEFINE_boolean force "${FLAGS_FALSE}" \
   "Force re-creating board root."
 DEFINE_boolean usepkg "${FLAGS_TRUE}" \
   "Use binary packages when possible."
+DEFINE_boolean usepkgonly "${FLAGS_FALSE}" \
+  "Only use/download binary packages."
 DEFINE_boolean getbinpkg "${FLAGS_TRUE}" \
   "Download binary packages from remote repository."
 DEFINE_string getbinpkgver "" \
@@ -135,12 +137,26 @@ if [ -z "$FLAGS_board" ] ; then
   exit 1
 fi
 
+if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+  for flag in usepkg getbinpkg; do
+    fvar="FLAGS_${flag}"
+    if [[ "${!fvar}" -ne "${FLAGS_TRUE}" ]]; then
+      die_notrace "--usepkgonly is incompatible with --no${flag}"
+    fi
+  done
+fi
+
 get_board_and_variant $FLAGS_board $FLAGS_variant
 
 # Before we can run any tools, we need to update chroot
 UPDATE_ARGS="--toolchain_boards=${BOARD}"
 if [ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}" ]; then
   UPDATE_ARGS+=" --usepkg"
+  if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+    UPDATE_ARGS+=" --usepkgonly"
+  else
+    UPDATE_ARGS+=" --usepkgonly"
+  fi
   if [[ "${FLAGS_getbinpkg}" -eq "${FLAGS_TRUE}" ]]; then
     UPDATE_ARGS+=" --getbinpkg "
   else
@@ -284,7 +300,12 @@ if [[ ${FLAGS_regen_configs} -eq ${FLAGS_FALSE} ]]; then
   if [[ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}"  && \
         "${FLAGS_getbinpkg}" -eq "${FLAGS_TRUE}" ]]
   then
-    EMERGE_FLAGS+=" --usepkg --getbinpkg"
+    if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+      EMERGE_FLAGS+=" --usepkgonly"
+    else
+      EMERGE_FLAGS+=" --usepkg"
+    fi
+    EMERGE_FLAGS+=" --getbinpkg"
     EMERGE_TOOLCHAIN_FLAGS+=" --usepkgonly --getbinpkg"
   else
     # When binary packages are disabled we need to make sure the cross

update_chroot

@@ -17,6 +17,10 @@ DEFINE_boolean usepkg "${FLAGS_TRUE}" \
   "Use binary packages when possible."
 DEFINE_boolean getbinpkg "${FLAGS_TRUE}" \
   "Download binary packages from remote repository."
+DEFINE_boolean usepkgonly "${FLAGS_FALSE}" \
+  "Only use/download binary packages. Implies --noworkon"
+DEFINE_boolean workon "${FLAGS_TRUE}" \
+  "Automatically rebuild updated cros-workon packages."
 DEFINE_integer jobs "${NUM_JOBS}" \
   "How many packages to build in parallel at maximum."
 DEFINE_boolean skip_toolchain_update "${FLAGS_FALSE}" \
@@ -37,6 +41,16 @@ eval set -- "${FLAGS_ARGV}"
 # so will die prematurely if 'switch_to_strict_mode' is specified before now.
 switch_to_strict_mode
 
+if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+  for flag in usepkg getbinpkg; do
+    fvar="FLAGS_${flag}"
+    if [[ "${!fvar}" -ne "${FLAGS_TRUE}" ]]; then
+      die_notrace "--usepkgonly is incompatible with --no${flag}"
+    fi
+  done
+  FLAGS_workon="${FLAGS_FALSE}"
+fi
+
 . "${BUILD_LIBRARY_DIR}/toolchain_util.sh"
 
 PORTAGE_STABLE_OVERLAY="${REPO_ROOT}/src/third_party/portage-stable"
@@ -166,6 +180,9 @@ EMERGE_FLAGS="-uNv --with-bdeps=y --select"
 REBUILD_FLAGS=""
 if [ "${FLAGS_usepkg}" -eq "${FLAGS_TRUE}" ]; then
   EMERGE_FLAGS="${EMERGE_FLAGS} --usepkg"
+  if [[ "${FLAGS_usepkgonly}" -eq "${FLAGS_TRUE}" ]]; then
+    EMERGE_FLAGS+=" --usepkgonly"
+  fi
   if [ "${FLAGS_getbinpkg}" -eq "${FLAGS_TRUE}" ]; then
     EMERGE_FLAGS="${EMERGE_FLAGS} --getbinpkg"
   fi
@@ -210,9 +227,11 @@ fi
 
 # Build cros_workon packages when they are changed.
 CHROMITE_BIN="${GCLIENT_ROOT}/chromite/bin"
-for pkg in $("${CHROMITE_BIN}/cros_list_modified_packages" --host); do
+if [ "${FLAGS_workon}" -eq "${FLAGS_TRUE}" ]; then
-  EMERGE_FLAGS+=" --reinstall-atoms=${pkg} --usepkg-exclude=${pkg}"
+  for pkg in $("${CHROMITE_BIN}/cros_list_modified_packages" --host); do
-done
+    EMERGE_FLAGS+=" --reinstall-atoms=${pkg} --usepkg-exclude=${pkg}"
+  done
+fi
 
 # Second pass, update everything else.
 EMERGE_FLAGS+=" --deep"