chrome/installer/mac/dmgdiffer.sh

   1 #!/bin/bash -p
   2
   3 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   4 # Use of this source code is governed by a BSD-style license that can be
   5 # found in the LICENSE file.
   6
   7 # usage: dmgdiffer.sh product_name old_dmg new_dmg patch_dmg
   8 #
   9 # dmgdiffer creates a disk image containing a binary update able to patch
  10 # a product originally distributed in old_dmg to the version in new_dmg. Much
  11 # of this script is generic, but the make_patch_fs function is specific to
  12 # a product: in this case, Google Chrome.
  13 #
  14 # This script operates by mounting old_dmg and new_dmg, creating a new
  15 # filesystem structure containing dirpatches generated by dirdiffer and
  16 # goobsdiff (which should be located in the same directory as this script),
  17 # and producing a disk image from that structure.
  18 #
  19 # The Chrome make_patch_fs function produces an disk image that is able to
  20 # update a single old version on any Keystone channel to a new version on a
  21 # specific Keystone channel (the Keystone channel associated with new_dmg).
  22 # Chrome's updates are split into two dirpatches: one updates the old
  23 # versioned directory to the new one, and the other updates the remainder of
  24 # the application. The versioned directory is split out from the rest because
  25 # it contains the bulk of the application and its name changes from version to
  26 # version, and dirdiffer/dirpatcher do not directly handle name changes. This
  27 # approach also allows the versioned directory dirpatch to be applied in-place
  28 # in most cases during an update, rather than relying on a temporary
  29 # directory. In order to allow a single update dmg to apply to an old version
  30 # on any Keystone channel, several small files are never distributed as diffs,
  31 # and only as full (possibly compressed) versions of the new files. These
  32 # files include the outer application's Info.plist which contains Keystone
  33 # channel information, and anything created or modified by code-signing the
  34 # outer application.
  35 #
  36 # Application of update disk images produced by this script is
  37 # product-specific. With updates managed by Keystone, the update disk images
  38 # can contain a .keystone_install script that is able to locate and update
  39 # the installed product.
  40 #
  41 # Exit codes:
  42 #  0  OK
  43 #  1  Unknown failure
  44 #  2  Incorrect number of parameters
  45 #  3  Input disk images do not exist
  46 #  4  Output disk image already exists
  47 #  5  Parent of output directory does not exist or is not a directory
  48 #  6  Could not mount old_dmg
  49 #  7  Could not mount new_dmg
  50 #  8  Could not create temporary patch filesystem directory
  51 #  9  Could not create disk image
  52 # 10  Could not read old application data
  53 # 11  Could not read new application data
  54 # 12  Old or new application sanity check failure
  55 # 13  Could not write the patch
  56 #
  57 # Exit codes in the range 21-40 are mapped to codes 1-20 as returned by the
  58 # first dirdiffer invocation. Codes 41-60 are mapped to codes 1-20 as returned
  59 # by the second.
  60
  61 set -eu
  62
  63 # Environment sanitization. Set a known-safe PATH. Clear environment variables
  64 # that might impact the interpreter's operation. The |bash -p| invocation
  65 # on the #! line takes the bite out of BASH_ENV, ENV, and SHELLOPTS (among
  66 # other features), but clearing them here ensures that they won't impact any
  67 # shell scripts used as utility programs. SHELLOPTS is read-only and can't be
  68 # unset, only unexported.
  69 export PATH="/usr/bin:/bin:/usr/sbin:/sbin"
  70 unset BASH_ENV CDPATH ENV GLOBIGNORE IFS POSIXLY_CORRECT
  71 export -n SHELLOPTS
  72
  73 ME="$(basename "${0}")"
  74 readonly ME
  75 SCRIPT_DIR="$(dirname "${0}")"
  76 readonly SCRIPT_DIR
  77 readonly DIRDIFFER="${SCRIPT_DIR}/dirdiffer.sh"
  78 readonly PKG_DMG="${SCRIPT_DIR}/pkg-dmg"
  79
  80 err() {
  81   local error="${1}"
  82
  83   echo "${ME}: ${error}" >& 2
  84 }
  85
  86 declare -a g_cleanup g_cleanup_mount_points
  87 cleanup() {
  88   local status=${?}
  89
  90   trap - EXIT
  91   trap '' HUP INT QUIT TERM
  92
  93   if [[ ${status} -ge 128 ]]; then
  94     err "Caught signal $((${status} - 128))"
  95   fi
  96
  97   if [[ "${#g_cleanup_mount_points[@]}" -gt 0 ]]; then
  98     local mount_point
  99     for mount_point in "${g_cleanup_mount_points[@]}"; do
 100       hdiutil detach "${mount_point}" -force >& /dev/null || true
 101     done
 102   fi
 103
 104   if [[ "${#g_cleanup[@]}" -gt 0 ]]; then
 105     rm -rf "${g_cleanup[@]}"
 106   fi
 107
 108   exit ${status}
 109 }
 110
 111 mount_dmg() {
 112   local dmg="${1}"
 113   local mount_point="${2}"
 114
 115   if ! hdiutil attach "${1}" -mountpoint "${2}" \
 116                              -nobrowse -owners off > /dev/null; then
 117     # set -e is in effect. return ${?} so that the caller can check the return
 118     # code if desired, perhaps to print a more useful error message or to exit
 119     # with a more precise status than would be possible here.
 120     return ${?}
 121   fi
 122 }
 123
 124 # make_patch_fs is responsible for comparing the old and new disk images
 125 # mounted at old_fs and new_fs, respectively, and populating patch_fs with the
 126 # contents of what will become a disk image able to update old_fs to new_fs.
 127 # It then outputs a string which will be used as the volume name of the
 128 # patch_dmg.
 129 #
 130 # The entire patch contents are placed into a .patch directory to hide them
 131 # from ordinary view. The disk image will be given a volume name like
 132 # "Google Chrome 5.0.375.55-5.0.375.70" as an identifying aid, although
 133 # uniqueness is not important and users will never interact directly with
 134 # them.
 135 make_patch_fs() {
 136   local product_name="${1}"
 137   local old_fs="${2}"
 138   local new_fs="${3}"
 139   local patch_fs="${4}"
 140
 141   readonly APP_NAME="${product_name}.app"
 142   readonly APP_NAME_RE="${product_name}\\.app"
 143   readonly APP_PLIST="Contents/Info"
 144   readonly APP_VERSION_KEY="CFBundleShortVersionString"
 145   readonly APP_BUNDLEID_KEY="CFBundleIdentifier"
 146   readonly KS_VERSION_KEY="KSVersion"
 147   readonly KS_PRODUCT_KEY="KSProductID"
 148   readonly KS_CHANNEL_KEY="KSChannelID"
 149   readonly VERSIONS_DIR="Contents/Versions"
 150   readonly BUILD_RE="^[0-9]+\\.[0-9]+\\.([0-9]+)\\.[0-9]+\$"
 151   readonly MIN_BUILD=434
 152
 153   local product_url="http://www.google.com/chrome/"
 154   if [[ "${product_name}" = "Google Chrome Canary" ]]; then
 155     product_url="http://tools.google.com/dlpage/chromesxs"
 156   fi
 157
 158   local old_app_path="${old_fs}/${APP_NAME}"
 159   local old_app_plist="${old_app_path}/${APP_PLIST}"
 160   local old_app_version
 161   if ! old_app_version="$(defaults read "${old_app_plist}" \
 162                                         "${APP_VERSION_KEY}")"; then
 163     err "could not read old app version"
 164     exit 10
 165   fi
 166   if ! [[ "${old_app_version}" =~ ${BUILD_RE} ]]; then
 167     err "old app version not of expected format"
 168     exit 10
 169   fi
 170   local old_app_version_build="${BASH_REMATCH[1]}"
 171
 172   local old_app_bundleid
 173   if ! old_app_bundleid="$(defaults read "${old_app_plist}" \
 174                                          "${APP_BUNDLEID_KEY}")"; then
 175     err "could not read old app bundle ID"
 176     exit 10
 177   fi
 178
 179   local old_ks_plist="${old_app_plist}"
 180   local old_ks_version
 181   if ! old_ks_version="$(defaults read "${old_ks_plist}" \
 182                                        "${KS_VERSION_KEY}")"; then
 183     err "could not read old Keystone version"
 184     exit 10
 185   fi
 186
 187   local new_app_path="${new_fs}/${APP_NAME}"
 188   local new_app_plist="${new_app_path}/${APP_PLIST}"
 189   local new_app_version
 190   if ! new_app_version="$(defaults read "${new_app_plist}" \
 191                       "${APP_VERSION_KEY}")"; then
 192     err "could not read new app version"
 193     exit 11
 194   fi
 195   if ! [[ "${new_app_version}" =~ ${BUILD_RE} ]]; then
 196     err "new app version not of expected format"
 197     exit 11
 198   fi
 199   local new_app_version_build="${BASH_REMATCH[1]}"
 200
 201   local new_ks_plist="${new_app_plist}"
 202   local new_ks_version
 203   if ! new_ks_version="$(defaults read "${new_ks_plist}" \
 204                                        "${KS_VERSION_KEY}")"; then
 205     err "could not read new Keystone version"
 206     exit 11
 207   fi
 208
 209   local new_ks_product
 210   if ! new_ks_product="$(defaults read "${new_app_plist}" \
 211                                        "${KS_PRODUCT_KEY}")"; then
 212     err "could not read new Keystone product ID"
 213     exit 11
 214   fi
 215
 216   if [[ ${old_app_version_build} -lt ${MIN_BUILD} ]] ||
 217      [[ ${new_app_version_build} -lt ${MIN_BUILD} ]]; then
 218     err "old and new versions must be build ${MIN_BUILD} or newer"
 219     exit 12
 220   fi
 221
 222   local new_ks_channel
 223   new_ks_channel="$(defaults read "${new_app_plist}" \
 224                     "${KS_CHANNEL_KEY}" 2> /dev/null || true)"
 225
 226   local name_extra
 227   if [[ "${new_ks_channel}" = "beta" ]]; then
 228     name_extra=" Beta"
 229   elif [[ "${new_ks_channel}" = "dev" ]]; then
 230     name_extra=" Dev"
 231   elif [[ "${new_ks_channel}" = "canary" ]]; then
 232     name_extra=
 233   elif [[ -n "${new_ks_channel}" ]]; then
 234     name_extra=" ${new_ks_channel}"
 235   fi
 236
 237   local old_versioned_dir="${old_app_path}/${VERSIONS_DIR}/${old_app_version}"
 238   local new_versioned_dir="${new_app_path}/${VERSIONS_DIR}/${new_app_version}"
 239
 240   if ! cp -p "${SCRIPT_DIR}/keystone_install.sh" \
 241              "${patch_fs}/.keystone_install"; then
 242     err "could not copy .keystone_install"
 243     exit 13
 244   fi
 245
 246   local patch_dotpatch_dir="${patch_fs}/.patch"
 247   if ! mkdir "${patch_dotpatch_dir}"; then
 248     err "could not mkdir patch_dotpatch_dir"
 249     exit 13
 250   fi
 251
 252   if ! cp -p "${SCRIPT_DIR}/dirpatcher.sh" \
 253              "${SCRIPT_DIR}/goobspatch" \
 254              "${SCRIPT_DIR}/liblzma_decompress.dylib" \
 255              "${SCRIPT_DIR}/xzdec" \
 256              "${patch_dotpatch_dir}/"; then
 257     err "could not copy patching tools"
 258     exit 13
 259   fi
 260
 261   if ! echo "${new_ks_product}" > "${patch_dotpatch_dir}/ks_product" ||
 262      ! echo "${old_app_version}" > "${patch_dotpatch_dir}/old_app_version" ||
 263      ! echo "${new_app_version}" > "${patch_dotpatch_dir}/new_app_version" ||
 264      ! echo "${old_ks_version}" > "${patch_dotpatch_dir}/old_ks_version" ||
 265      ! echo "${new_ks_version}" > "${patch_dotpatch_dir}/new_ks_version"; then
 266     err "could not write patch product or version information"
 267     exit 13
 268   fi
 269   local patch_ks_channel_file="${patch_dotpatch_dir}/ks_channel"
 270   if [[ -n "${new_ks_channel}" ]]; then
 271     if ! echo "${new_ks_channel}" > "${patch_ks_channel_file}"; then
 272       err "could not write Keystone channel information"
 273       exit 13
 274     fi
 275   else
 276     if ! touch "${patch_ks_channel_file}"; then
 277       err "could not write empty Keystone channel information"
 278       exit 13
 279     fi
 280   fi
 281
 282   # The only visible contents of the disk image will be a README file that
 283   # explains the image's purpose.
 284   local new_app_version_extra="${new_app_version}${name_extra}"
 285   cat > "${patch_fs}/README.txt" << __EOF__ || \
 286       (err "could not write README.txt" && exit 13)
 287 This disk image contains a differential updater that can update
 288 ${product_name} from version ${old_app_version} to ${new_app_version_extra}.
 289
 290 This image is part of the auto-update system and is not independently
 291 useful.
 292
 293 To install ${product_name}, please visit
 294 <${product_url}>.
 295 __EOF__
 296
 297   local patch_versioned_dir="\
 298 ${patch_dotpatch_dir}/version_${old_app_version}_${new_app_version}.dirpatch"
 299
 300   if ! "${DIRDIFFER}" "${old_versioned_dir}" \
 301                       "${new_versioned_dir}" \
 302                       "${patch_versioned_dir}"; then
 303     local status=${?}
 304     err "could not create a dirpatch for the versioned directory"
 305     exit $((${status} + 20))
 306   fi
 307
 308   # Set DIRDIFFER_EXCLUDE to exclude the contents of the Versions directory,
 309   # but to include an empty Versions directory. The versioned directory was
 310   # already addressed in the preceding dirpatch.
 311   export DIRDIFFER_EXCLUDE="/${APP_NAME_RE}/Contents/Versions/"
 312
 313   # Set DIRDIFFER_NO_DIFF to exclude files introduced by or modified by
 314   # Keystone channel and brand tagging and subsequent code signing.
 315   export DIRDIFFER_NO_DIFF="\
 316 /${APP_NAME_RE}/Contents/\
 317 (CodeResources|Info\\.plist|MacOS/${product_name}|_CodeSignature/.*)$"
 318
 319   local patch_app_dir="${patch_dotpatch_dir}/application.dirpatch"
 320
 321   if ! "${DIRDIFFER}" "${old_app_path}" \
 322                       "${new_app_path}" \
 323                       "${patch_app_dir}"; then
 324     local status=${?}
 325     err "could not create a dirpatch for the application directory"
 326     exit $((${status} + 40))
 327   fi
 328
 329   unset DIRDIFFER_EXCLUDE DIRDIFFER_NO_DIFF
 330
 331   echo "${product_name} ${old_app_version}-${new_app_version_extra} Update"
 332 }
 333
 334 # package_patch_dmg creates a disk image at patch_dmg with the contents of
 335 # patch_fs. The disk image's volume name is taken from volume_name. temp_dir
 336 # is a work directory such as /tmp for the packager's use.
 337 package_patch_dmg() {
 338   local patch_fs="${1}"
 339   local patch_dmg="${2}"
 340   local volume_name="${3}"
 341   local temp_dir="${4}"
 342
 343   # Because most of the contents of ${patch_fs} are already compressed, the
 344   # overall compression on the disk image is mostly used to minimize the sizes
 345   # of the filesystem structures. In the presence of so much
 346   # already-compressed data, zlib performs better than bzip2, so use UDZO.
 347   if ! "${PKG_DMG}" \
 348            --verbosity 0 \
 349            --source "${patch_fs}" \
 350            --target "${patch_dmg}" \
 351            --tempdir "${temp_dir}" \
 352            --format UDZO \
 353            --volname "${volume_name}" \
 354            --config "openfolder_bless=0"; then
 355     err "disk image creation failed"
 356     exit 9
 357   fi
 358 }
 359
 360 # make_patch_dmg mounts old_dmg and new_dmg, invokes make_patch_fs to prepare
 361 # a patch filesystem, and then hands the patch filesystem to package_patch_dmg
 362 # to create patch_dmg.
 363 make_patch_dmg() {
 364   local product_name="${1}"
 365   local old_dmg="${2}"
 366   local new_dmg="${3}"
 367   local patch_dmg="${4}"
 368
 369   local temp_dir
 370   temp_dir="$(mktemp -d -t "${ME}")"
 371   g_cleanup+=("${temp_dir}")
 372
 373   local old_mount_point="${temp_dir}/old"
 374   g_cleanup_mount_points+=("${old_mount_point}")
 375   if ! mount_dmg "${old_dmg}" "${old_mount_point}"; then
 376     err "could not mount old_dmg ${old_dmg}"
 377     exit 6
 378   fi
 379
 380   local new_mount_point="${temp_dir}/new"
 381   g_cleanup_mount_points+=("${new_mount_point}")
 382   if ! mount_dmg "${new_dmg}" "${new_mount_point}"; then
 383     err "could not mount new_dmg ${new_dmg}"
 384     exit 7
 385   fi
 386
 387   local patch_fs="${temp_dir}/patch"
 388   if ! mkdir "${patch_fs}"; then
 389     err "could not mkdir patch_fs ${patch_fs}"
 390     exit 8
 391   fi
 392
 393   local volume_name
 394   volume_name="$(make_patch_fs "${product_name}" \
 395                                "${old_mount_point}" \
 396                                "${new_mount_point}" \
 397                                "${patch_fs}")"
 398
 399   hdiutil detach "${new_mount_point}" > /dev/null
 400   unset g_cleanup_mount_points[${#g_cleanup_mount_points[@]}]
 401
 402   hdiutil detach "${old_mount_point}" > /dev/null
 403   unset g_cleanup_mount_points[${#g_cleanup_mount_points[@]}]
 404
 405   package_patch_dmg "${patch_fs}" "${patch_dmg}" "${volume_name}" "${temp_dir}"
 406
 407   rm -rf "${temp_dir}"
 408   unset g_cleanup[${#g_cleanup[@]}]
 409 }
 410
 411 # shell_safe_path ensures that |path| is safe to pass to tools as a
 412 # command-line argument. If the first character in |path| is "-", "./" is
 413 # prepended to it. The possibly-modified |path| is output.
 414 shell_safe_path() {
 415   local path="${1}"
 416   if [[ "${path:0:1}" = "-" ]]; then
 417     echo "./${path}"
 418   else
 419     echo "${path}"
 420   fi
 421 }
 422
 423 usage() {
 424   echo "usage: ${ME} product_name old_dmg new_dmg patch_dmg" >& 2
 425 }
 426
 427 main() {
 428   local product_name old_dmg new_dmg patch_dmg
 429   product_name="${1}"
 430   old_dmg="$(shell_safe_path "${2}")"
 431   new_dmg="$(shell_safe_path "${3}")"
 432   patch_dmg="$(shell_safe_path "${4}")"
 433
 434   trap cleanup EXIT HUP INT QUIT TERM
 435
 436   if ! [[ -f "${old_dmg}" ]] || ! [[ -f "${new_dmg}" ]]; then
 437     err "old_dmg and new_dmg must exist and be files"
 438     usage
 439     exit 3
 440   fi
 441
 442   if [[ -e "${patch_dmg}" ]]; then
 443     err "patch_dmg must not exist"
 444     usage
 445     exit 4
 446   fi
 447
 448   local patch_dmg_parent
 449   patch_dmg_parent="$(dirname "${patch_dmg}")"
 450   if ! [[ -d "${patch_dmg_parent}" ]]; then
 451     err "patch_dmg parent directory must exist and be a directory"
 452     usage
 453     exit 5
 454   fi
 455
 456   make_patch_dmg "${product_name}" "${old_dmg}" "${new_dmg}" "${patch_dmg}"
 457
 458   trap - EXIT
 459 }
 460
 461 if [[ ${#} -ne 4 ]]; then
 462   usage
 463   exit 2
 464 fi
 465
 466 main "${@}"
 467 exit ${?}