image_to_usb.sh: detect and allow to select between candidate images.

The script does not assume a single source image (chromiumos_image.bin)
but detects which images of a list of candidate images are present, and
lets the user select one.  The default choice is the first image in the
list to be detected.  If only one image was detected, it will be
automatically selected.  The list contains the aforementioned standard
image, as well as the default names for recovery, test, factory and
factory install images.  If the script is invoked with --test, --factory
or --factory_install flags, it will only seek for the standard image
(and attempt to generate the desired image from it, as was previously
done).

Also fixed some log messages; option strings; and improved the logic for
unmounting the target device, eliminating an unnecessary message and
a 3 second delay.

BUG=chromium-os:26010
TEST=Tested image_to_usb.sh with different images and flags.
CQ-DEPEND=I53a42a46a3c90fd486fead578bfbae248f64cfc2

Change-Id: I0d2f20dc8d62ce5fa18c10d9f8b51a46b2ddca5d
Reviewed-on: https://gerrit.chromium.org/gerrit/15528
Reviewed-by: Richard Barnette <jrbarnette@chromium.org>
Tested-by: Gilad Arnold <garnold@chromium.org>
Commit-Ready: Gilad Arnold <garnold@chromium.org>

image_to_usb.sh

@@ -41,30 +41,38 @@ declare -F list_mmc_disks >/dev/null || list_mmc_disks() { true; }
 get_default_board
 
 # Flags
-DEFINE_string board "${DEFAULT_BOARD}" "Board for which the image was built"
+DEFINE_string board "${DEFAULT_BOARD}" \
+  "board for which the image was built"
 DEFINE_string from "" \
-  "Directory containing ${CHROMEOS_IMAGE_NAME}, or filename"
+  "directory containing the image, or image full pathname"
-DEFINE_string to "/dev/sdX" "Write to a specific disk or image file."
+DEFINE_string to "/dev/sdX" \
+  "write to a specific disk or image file"
 DEFINE_string to_product "" \
-  "Write to a disk with product name matching a pattern."
+  "write to a disk with product name matching a pattern"
-DEFINE_boolean yes ${FLAGS_FALSE} "Answer yes to all prompts" "y"
+DEFINE_boolean yes ${FLAGS_FALSE} \
-DEFINE_boolean force_copy ${FLAGS_FALSE} "Always rebuild test image"
+  "answer yes to all prompts" \
+  y
+DEFINE_boolean force_copy ${FLAGS_FALSE} \
+  "always rebuild test image"
 DEFINE_boolean force_non_usb ${FLAGS_FALSE} \
-  "Write out image even if target (--to) doesn't look like a USB or MMC disk"
+  "force writing even if target device doesn't appear to be a USB/MMC disk"
 DEFINE_boolean factory_install ${FLAGS_FALSE} \
-  "Whether to generate a factory install shim."
+  "generate a factory install shim"
 DEFINE_boolean factory ${FLAGS_FALSE} \
-  "Whether to generate a factory runin image. Implies aututest and test"
+  "generate a factory runing image, implies autotest and test"
 DEFINE_boolean copy_kernel ${FLAGS_FALSE} \
-  "Copy the kernel to the fourth partition."
+  "copy the kernel to the fourth partition"
 DEFINE_boolean test_image "${FLAGS_FALSE}" \
-  "Copies normal image to ${CHROMEOS_TEST_IMAGE_NAME}, modifies it for test."
+  "copy normal image to ${CHROMEOS_TEST_IMAGE_NAME} and modify it for test"
-DEFINE_string image_name "${CHROMEOS_IMAGE_NAME}" \
+DEFINE_string image_name "" \
-  "Base name of the image" i
+  "image base name (auto-select if empty)" \
+  i
 DEFINE_string build_root "/build" \
-  "The root location for board sysroots."
+  "root location for board sysroots"
-DEFINE_boolean install ${FLAGS_FALSE} "Install to the USB or MMC device."
+DEFINE_boolean install ${FLAGS_FALSE} \
-DEFINE_string arch "" "Architecture of the image."
+  "install to the USB/MMC device"
+DEFINE_string arch "" \
+  "architecture for which the image was built (derived from board if empty)"
 
 # Parse command line
 FLAGS "$@" || exit 1
@@ -162,7 +170,7 @@ fi
 
 # No target provided, attempt autodetection.
 if [ "${FLAGS_to}" == "/dev/sdX" ]; then
-  echo "No target device was specified, autodetecting..."
+  echo "No target device specified, autodetecting..."
 
   # Obtain list of USB and MMC device names.
   disk_list=( $(list_usb_disks) $(list_mmc_disks) )
@@ -225,6 +233,45 @@ fi
 STATEFUL_DIR="${FLAGS_from}/stateful_partition"
 mkdir -p "${STATEFUL_DIR}"
 
+# Autodetect image.
+if [ -z "${FLAGS_image_name}" ]; then
+  echo "No image name specified, autodetecting..."
+
+  # Obtain list of available images that can be used.
+  image_candidate_list=( "${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[@]}"
+                           "${CHROMEOS_RECOVERY_IMAGE_NAME}"
+                           "${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[@]}" "${image_candidate}" )
+    fi
+  done
+
+  num_images=${#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
+
 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}" "${FLAGS_image_name}"
@@ -242,7 +289,7 @@ fi
 if [ -b "${FLAGS_to}" ]; then
   # Output to a block device (i.e., a real USB key / SD card), so need sudo dd
   if [ ${FLAGS_install} -ne ${FLAGS_TRUE} ]; then
-    echo "Copying USB image ${SRC_IMAGE} to ${FLAGS_to}..."
+    echo "Copying image ${SRC_IMAGE} to ${FLAGS_to}..."
   else
     echo "Installing image ${SRC_IMAGE} to ${FLAGS_to}..."
   fi
@@ -272,16 +319,18 @@ if [ -b "${FLAGS_to}" ]; then
     fi
   fi
 
+  mount_list=$(mount | grep ^"${FLAGS_to}" | awk '{print $1}')
+  if [ -n "${mount_list}" ]; then
     echo "Attempting to unmount any mounts on the target device..."
-  for i in $(mount | grep ^"${FLAGS_to}" | awk '{print $1}'); do
+    for i in ${mount_list}; do
       if sudo umount "$i" 2>&1 >/dev/null | grep "not found"; then
         die "Device ${FLAGS_to} needs to be unmounted outside the chroot"
       fi
     done
     sleep 3
+  fi
 
   if [ ${FLAGS_install} -ne ${FLAGS_TRUE} ]; then
-    echo "Copying with dd ${SRC_IMAGE} to ${FLAGS_to}..."
     sudo ${COMMON_PV_CAT} "${SRC_IMAGE}" |
       sudo dd of="${FLAGS_to}" bs=4M oflag=sync status=noxfer
     sync
@@ -290,7 +339,6 @@ if [ -b "${FLAGS_to}" ]; then
       die "Installation must be done from inside the chroot"
     fi
 
-    echo "Installing ${SRC_IMAGE} to ${FLAGS_to}..."
     "${FLAGS_build_root}/${FLAGS_board}/usr/sbin/chromeos-install" \
       --yes \
       --skip_src_removable \
@@ -299,7 +347,6 @@ if [ -b "${FLAGS_to}" ]; then
       --payload_image="${SRC_IMAGE}" \
       --dst="${FLAGS_to}"
   fi
-  echo "Done."
 else
   # Output to a file, so just make a copy.
   if [ "${SRC_IMAGE}" != "${FLAGS_to}" ]; then
@@ -307,7 +354,8 @@ else
     ${COMMON_PV_CAT} "${SRC_IMAGE}" >"${FLAGS_to}"
   fi
 
-  echo "Done.  To copy to a USB/MMC drive, do something like:"
+  info "To copy onto a USB/MMC drive /dev/sdX, use: "
-  echo "   sudo dd if=${FLAGS_to} of=/dev/sdX bs=4M oflag=sync"
+  info "  sudo dd if=${FLAGS_to} of=/dev/sdX bs=4M oflag=sync"
-  echo "where /dev/sdX is the entire drive."
 fi
+
+echo "Done."