From dd59d7e9a6f54d2f2decd4ff247101db998c376e Mon Sep 17 00:00:00 2001
From: Gilad Arnold <garnold@chromium.org>
Date: Mon, 13 Feb 2012 11:31:58 -0800
Subject: [PATCH] image_to_usb.sh: do not require chromiumos_image.bin when
 --test_image is used.

The recent changes to image_to_usb.sh assumed that chromiumos_image.bin
is always used for generating a test image. This wasn't the case before
these changes were applied, where a preexisting test image would have
sufficed.  This fix eliminates image autodetection entirely when
--test_image it used and falls back to the old behavior: if a test image
exists, it will use it; otherwise, it will generate it from the image
specified by --image_name, or from the default chromiumos_image.bin.

This is not to say that I like this behavior: it is subtle, may lead to
errors (e.g. using a stale test image whereas the user assumes a new one
should be generated), and inconsistent with other behaviors (e.g.
installing a recovery image, where no image generation takes place at
all).  I believe that long term we should eliminate the generation of
test images from image_to_usb.sh and have users invoke the necessary
scripts (like mod_image_for_test.sh) explicitly.

BUG=chromium-os:26239
TEST=Ran script with different combinations of --test_image,
--image_name and image files present.

Change-Id: Ib2491a7e45e23eb51ced6ef31d3f129ec7863a25
Reviewed-on: https://gerrit.chromium.org/gerrit/15764
Reviewed-by: Richard Barnette <jrbarnette@chromium.org>
Commit-Ready: Gilad Arnold <garnold@chromium.org>
Tested-by: Gilad Arnold <garnold@chromium.org>
---
 image_to_usb.sh       | 74 ++++++++++++++++++++++---------------------
 mod_image_for_test.sh |  2 +-
 2 files changed, 39 insertions(+), 37 deletions(-)

diff --git a/image_to_usb.sh b/image_to_usb.sh
index 173fa14ff1..ab61816b4b 100755
--- a/image_to_usb.sh
+++ b/image_to_usb.sh
@@ -230,54 +230,56 @@ fi
 STATEFUL_DIR="${FLAGS_from}/stateful_partition"
 mkdir -p "${STATEFUL_DIR}"
 
-# Autodetect image.
-if [ -z "${FLAGS_image_name}" ]; then
-  echo "No image name specified, autodetecting..."
+# Figure out which image to use.
+if [ ${FLAGS_test_image} -eq ${FLAGS_TRUE} ]; then
+  # Test image requested: pass the provided (or otherwise default) image name
+  # to the method that's in charge of preparing a test image (note that this
+  # image may or may not exist). The test image filename is returned in
+  # CHROMEOS_RETURN_VAL.
+  prepare_test_image "${FLAGS_from}" \
+    "${FLAGS_image_name:=${CHROMEOS_IMAGE_NAME}}"
+  SRC_IMAGE="${CHROMEOS_RETURN_VAL}"
+else
+  # Auto-detect and select an image name if none provided.
+  if [ -z "${FLAGS_image_name}" ]; then
+    echo "No image name specified, autodetecting..."
 
-  # Obtain list of available images that can be used.
-  image_candidate_list=( "${CHROMEOS_IMAGE_NAME}" )
-  if [ ${FLAGS_test_image} -eq ${FLAGS_FALSE} ]; then
-    # Generation of test image not signaled, look for other images as well.
-    image_candidate_list=( "${image_candidate_list[@]}"
+    # Obtain list of available images that can be used.
+    image_candidate_list=( "${CHROMEOS_IMAGE_NAME}"
                            "${CHROMEOS_RECOVERY_IMAGE_NAME}"
                            "${CHROMEOS_TEST_IMAGE_NAME}"
                            "${CHROMEOS_FACTORY_TEST_IMAGE_NAME}"
                            "${CHROMEOS_FACTORY_INSTALL_SHIM_NAME}" )
-  fi
-  unset image_list
-  for image_candidate in "${image_candidate_list[@]}"; do
-    if [ -f "${FLAGS_from}/${image_candidate}" ]; then
-      image_list=( "${image_list[@]}" "${image_candidate}" )
-    fi
-  done
+    unset image_list
+    for image_candidate in "${image_candidate_list[@]}"; do
+      if [ -f "${FLAGS_from}/${image_candidate}" ]; then
+        image_list=( "${image_list[@]}" "${image_candidate}" )
+      fi
+    done
 
-  num_images=${#image_list[*]}
-  if (( ${num_images} == 0 )); then
-    die "No candidate images could be detected"
-  elif (( ${num_images} == 1)); then
-    image="${image_list}"
-    echo "Found image ${image}"
-  else
-    # Select one from a list of available images; default to the first.
-    PS3="Select an image [1]: "
-    choose image "${image_list}" "ERROR" "${image_list[@]}"
-    if [ "${image}" == "ERROR" ]; then
-      die "Invalid selection"
+    num_images=${#image_list[*]}
+    if (( ${num_images} == 0 )); then
+      die "No candidate images could be detected"
+    elif (( ${num_images} == 1)); then
+      image="${image_list}"
+      echo "Found image ${image}"
+    else
+      # Select one from a list of available images; default to the first.
+      PS3="Select an image [1]: "
+      choose image "${image_list}" "ERROR" "${image_list[@]}"
+      if [ "${image}" == "ERROR" ]; then
+        die "Invalid selection"
+      fi
     fi
+
+    FLAGS_image_name="${image}"
   fi
 
-  FLAGS_image_name="${image}"
-fi
-
-if [ ${FLAGS_test_image} -eq ${FLAGS_TRUE} ] ; then
-  # Make a test image - this returns the test filename in CHROMEOS_RETURN_VAL
-  prepare_test_image "${FLAGS_from}" "${FLAGS_image_name}"
-  SRC_IMAGE="${CHROMEOS_RETURN_VAL}"
-else
-  # Use the standard image
+  # Use the selected image.
   SRC_IMAGE="${FLAGS_from}/${FLAGS_image_name}"
 fi
 
+# Make sure that the selected image exists.
 if [ ! -f "${SRC_IMAGE}" ]; then
   die "Image not found: ${SRC_IMAGE}"
 fi
diff --git a/mod_image_for_test.sh b/mod_image_for_test.sh
index 07240b42d3..7ee3b1d79b 100755
--- a/mod_image_for_test.sh
+++ b/mod_image_for_test.sh
@@ -78,7 +78,7 @@ if [ $FLAGS_inplace -eq $FLAGS_FALSE ]; then
     copy_image $(basename "$FLAGS_image") $(basename "$TEST_PATHNAME")
     FLAGS_image="$TEST_PATHNAME"
   else
-    echo "Using cached $(basename "$FLAGS_image")"
+    echo "Using cached $(basename "${TEST_PATHNAME}")"
     exit
   fi