src/chrome/installer/mac/dirpatcher.sh

   1 #!/bin/bash -p
   2
   3 # Copyright (c) 2011 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: dirpatcher.sh old_dir patch_dir new_dir
   8 #
   9 # dirpatcher creates new_dir from patch_dir by decompressing and copying
  10 # files, and using goobspatch to apply binary diffs to files in old_dir.
  11 #
  12 # dirpatcher performs the inverse operation to dirdiffer. For more details,
  13 # consult dirdiffer.sh.
  14 #
  15 # Exit codes:
  16 #  0  OK
  17 #  1  Unknown failure
  18 #  2  Incorrect number of parameters
  19 #  3  Input directories do not exist or are not directories
  20 #  4  Output directory already exists
  21 #  5  Parent of output directory does not exist or is not a directory
  22 #  6  An input or output directories contains another
  23 #  7  Could not create output directory
  24 #  8  File already exists in output directory
  25 #  9  Found an irregular file (non-directory, file, or symbolic link) in input
  26 # 10  Could not create symbolic link
  27 # 11  Unrecognized file extension
  28 # 12  Attempt to patch a nonexistent or non-regular file
  29 # 13  Patch application failed
  30 # 14  File decompression failed
  31 # 15  File copy failed
  32 # 16  Could not set mode (permissions)
  33 # 17  Could not set modification time
  34
  35 set -eu
  36
  37 # Environment sanitization. Set a known-safe PATH. Clear environment variables
  38 # that might impact the interpreter's operation. The |bash -p| invocation
  39 # on the #! line takes the bite out of BASH_ENV, ENV, and SHELLOPTS (among
  40 # other features), but clearing them here ensures that they won't impact any
  41 # shell scripts used as utility programs. SHELLOPTS is read-only and can't be
  42 # unset, only unexported.
  43 export PATH="/usr/bin:/bin:/usr/sbin:/sbin"
  44 unset BASH_ENV CDPATH ENV GLOBIGNORE IFS POSIXLY_CORRECT
  45 export -n SHELLOPTS
  46
  47 shopt -s dotglob nullglob
  48
  49 # find_tool looks for an executable file named |tool_name|:
  50 #  - in the same directory as this script,
  51 #  - if this script is located in a Chromium source tree, at the expected
  52 #    Release output location in the Mac out directory,
  53 #  - as above, but in the Debug output location
  54 # If found in any of the above locations, the script's path is output.
  55 # Otherwise, this function outputs |tool_name| as a fallback, allowing it to
  56 # be found (or not) by an ordinary ${PATH} search.
  57 find_tool() {
  58   local tool_name="${1}"
  59
  60   local script_dir
  61   script_dir="$(dirname "${0}")"
  62
  63   local tool="${script_dir}/${tool_name}"
  64   if [[ -f "${tool}" ]] && [[ -x "${tool}" ]]; then
  65     echo "${tool}"
  66     return
  67   fi
  68
  69   local script_dir_phys
  70   script_dir_phys="$(cd "${script_dir}" && pwd -P)"
  71   if [[ "${script_dir_phys}" =~ ^(.*)/src/chrome/installer/mac$ ]]; then
  72     tool="${BASH_REMATCH[1]}/src/out/Release/${tool_name}"
  73     if [[ -f "${tool}" ]] && [[ -x "${tool}" ]]; then
  74       echo "${tool}"
  75       return
  76     fi
  77
  78     tool="${BASH_REMATCH[1]}/src/out/Debug/${tool_name}"
  79     if [[ -f "${tool}" ]] && [[ -x "${tool}" ]]; then
  80       echo "${tool}"
  81       return
  82     fi
  83   fi
  84
  85   echo "${tool_name}"
  86 }
  87
  88 ME="$(basename "${0}")"
  89 readonly ME
  90 GOOBSPATCH="$(find_tool goobspatch)"
  91 readonly GOOBSPATCH
  92 readonly BUNZIP2="bunzip2"
  93 readonly GUNZIP="gunzip"
  94 XZDEC="$(find_tool xzdec)"
  95 readonly XZDEC
  96 readonly GBS_SUFFIX='$gbs'
  97 readonly BZ2_SUFFIX='$bz2'
  98 readonly GZ_SUFFIX='$gz'
  99 readonly XZ_SUFFIX='$xz'
 100 readonly PLAIN_SUFFIX='$raw'
 101
 102 err() {
 103   local error="${1}"
 104
 105   echo "${ME}: ${error}" >& 2
 106 }
 107
 108 declare -a g_cleanup
 109 cleanup() {
 110   local status=${?}
 111
 112   trap - EXIT
 113   trap '' HUP INT QUIT TERM
 114
 115   if [[ ${status} -ge 128 ]]; then
 116     err "Caught signal $((${status} - 128))"
 117   fi
 118
 119   if [[ "${#g_cleanup[@]}" -gt 0 ]]; then
 120     rm -rf "${g_cleanup[@]}"
 121   fi
 122
 123   exit ${status}
 124 }
 125
 126 copy_mode_and_time() {
 127   local patch_file="${1}"
 128   local new_file="${2}"
 129
 130   local mode
 131   mode="$(stat "-f%OMp%OLp" "${patch_file}")"
 132   if ! chmod -h "${mode}" "${new_file}"; then
 133     exit 16
 134   fi
 135
 136   if ! [[ -L "${new_file}" ]]; then
 137     # Symbolic link modification times can't be copied because there's no
 138     # shell tool that provides direct access to lutimes. Instead, the symbolic
 139     # link was created with rsync, which already copied the timestamp with
 140     # lutimes.
 141     if ! touch -r "${patch_file}" "${new_file}"; then
 142       exit 17
 143     fi
 144   fi
 145 }
 146
 147 apply_patch() {
 148   local old_file="${1}"
 149   local patch_file="${2}"
 150   local new_file="${3}"
 151   local patcher="${4}"
 152
 153   if [[ -L "${old_file}" ]] || ! [[ -f "${old_file}" ]]; then
 154     err "can't patch nonexistent or irregular file ${old_file}"
 155     exit 12
 156   fi
 157
 158   if ! "${patcher}" "${old_file}" "${new_file}" "${patch_file}"; then
 159     err "couldn't create ${new_file} by applying ${patch_file} to ${old_file}"
 160     exit 13
 161   fi
 162 }
 163
 164 decompress_file() {
 165   local old_file="${1}"
 166   local patch_file="${2}"
 167   local new_file="${3}"
 168   local decompressor="${4}"
 169
 170   if ! "${decompressor}" -c < "${patch_file}" > "${new_file}"; then
 171     err "couldn't decompress ${patch_file} to ${new_file} with ${decompressor}"
 172     exit 14
 173   fi
 174 }
 175
 176 copy_file() {
 177   local old_file="${1}"
 178   local patch_file="${2}"
 179   local new_file="${3}"
 180   local extra="${4}"
 181
 182   if ! cp "${patch_file}" "${new_file}"; then
 183     exit 15
 184   fi
 185 }
 186
 187 patch_file() {
 188   local old_file="${1}"
 189   local patch_file="${2}"
 190   local new_file="${3}"
 191
 192   local operation extra strip_length
 193
 194   if [[ "${patch_file: -${#GBS_SUFFIX}}" = "${GBS_SUFFIX}" ]]; then
 195     operation="apply_patch"
 196     extra="${GOOBSPATCH}"
 197     strip_length=${#GBS_SUFFIX}
 198   elif [[ "${patch_file: -${#BZ2_SUFFIX}}" = "${BZ2_SUFFIX}" ]]; then
 199     operation="decompress_file"
 200     extra="${BUNZIP2}"
 201     strip_length=${#BZ2_SUFFIX}
 202   elif [[ "${patch_file: -${#GZ_SUFFIX}}" = "${GZ_SUFFIX}" ]]; then
 203     operation="decompress_file"
 204     extra="${GUNZIP}"
 205     strip_length=${#GZ_SUFFIX}
 206   elif [[ "${patch_file: -${#XZ_SUFFIX}}" = "${XZ_SUFFIX}" ]]; then
 207     operation="decompress_file"
 208     extra="${XZDEC}"
 209     strip_length=${#XZ_SUFFIX}
 210   elif [[ "${patch_file: -${#PLAIN_SUFFIX}}" = "${PLAIN_SUFFIX}" ]]; then
 211     operation="copy_file"
 212     extra="patch"
 213     strip_length=${#PLAIN_SUFFIX}
 214   else
 215     err "don't know how to operate on ${patch_file}"
 216     exit 11
 217   fi
 218
 219   old_file="${old_file:0:${#old_file} - ${strip_length}}"
 220   new_file="${new_file:0:${#new_file} - ${strip_length}}"
 221
 222   if [[ -e "${new_file}" ]]; then
 223     err "${new_file} already exists"
 224     exit 8
 225   fi
 226
 227   "${operation}" "${old_file}" "${patch_file}" "${new_file}" "${extra}"
 228
 229   copy_mode_and_time "${patch_file}" "${new_file}"
 230 }
 231
 232 patch_symlink() {
 233   local patch_file="${1}"
 234   local new_file="${2}"
 235
 236   # local target
 237   # target="$(readlink "${patch_file}")"
 238   # ln -s "${target}" "${new_file}"
 239
 240   # Use rsync instead of the above, as it's the only way to preserve the
 241   # timestamp of a symbolic link using shell tools.
 242   if ! rsync -lt "${patch_file}" "${new_file}"; then
 243     exit 10
 244   fi
 245
 246   copy_mode_and_time "${patch_file}" "${new_file}"
 247 }
 248
 249 patch_dir() {
 250   local old_dir="${1}"
 251   local patch_dir="${2}"
 252   local new_dir="${3}"
 253
 254   if ! mkdir "${new_dir}"; then
 255     exit 7
 256   fi
 257
 258   local patch_file
 259   for patch_file in "${patch_dir}/"*; do
 260     local file="${patch_file:${#patch_dir} + 1}"
 261     local old_file="${old_dir}/${file}"
 262     local new_file="${new_dir}/${file}"
 263
 264     if [[ -e "${new_file}" ]]; then
 265       err "${new_file} already exists"
 266       exit 8
 267     fi
 268
 269     if [[ -L "${patch_file}" ]]; then
 270       patch_symlink "${patch_file}" "${new_file}"
 271     elif [[ -d "${patch_file}" ]]; then
 272       patch_dir "${old_file}" "${patch_file}" "${new_file}"
 273     elif ! [[ -f "${patch_file}" ]]; then
 274       err "can't handle irregular file ${patch_file}"
 275       exit 9
 276     else
 277       patch_file "${old_file}" "${patch_file}" "${new_file}"
 278     fi
 279   done
 280
 281   copy_mode_and_time "${patch_dir}" "${new_dir}"
 282 }
 283
 284 # shell_safe_path ensures that |path| is safe to pass to tools as a
 285 # command-line argument. If the first character in |path| is "-", "./" is
 286 # prepended to it. The possibly-modified |path| is output.
 287 shell_safe_path() {
 288   local path="${1}"
 289   if [[ "${path:0:1}" = "-" ]]; then
 290     echo "./${path}"
 291   else
 292     echo "${path}"
 293   fi
 294 }
 295
 296 dirs_contained() {
 297   local dir1="${1}/"
 298   local dir2="${2}/"
 299
 300   if [[ "${dir1:0:${#dir2}}" = "${dir2}" ]] ||
 301      [[ "${dir2:0:${#dir1}}" = "${dir1}" ]]; then
 302     return 0
 303   fi
 304
 305   return 1
 306 }
 307
 308 usage() {
 309   echo "usage: ${ME} old_dir patch_dir new_dir" >& 2
 310 }
 311
 312 main() {
 313   local old_dir patch_dir new_dir
 314   old_dir="$(shell_safe_path "${1}")"
 315   patch_dir="$(shell_safe_path "${2}")"
 316   new_dir="$(shell_safe_path "${3}")"
 317
 318   trap cleanup EXIT HUP INT QUIT TERM
 319
 320   if ! [[ -d "${old_dir}" ]] || ! [[ -d "${patch_dir}" ]]; then
 321     err "old_dir and patch_dir must exist and be directories"
 322     usage
 323     exit 3
 324   fi
 325
 326   if [[ -e "${new_dir}" ]]; then
 327     err "new_dir must not exist"
 328     usage
 329     exit 4
 330   fi
 331
 332   local new_dir_parent
 333   new_dir_parent="$(dirname "${new_dir}")"
 334   if ! [[ -d "${new_dir_parent}" ]]; then
 335     err "new_dir parent directory must exist and be a directory"
 336     usage
 337     exit 5
 338   fi
 339
 340   local old_dir_phys patch_dir_phys new_dir_parent_phys new_dir_phys
 341   old_dir_phys="$(cd "${old_dir}" && pwd -P)"
 342   patch_dir_phys="$(cd "${patch_dir}" && pwd -P)"
 343   new_dir_parent_phys="$(cd "${new_dir_parent}" && pwd -P)"
 344   new_dir_phys="${new_dir_parent_phys}/$(basename "${new_dir}")"
 345
 346   if dirs_contained "${old_dir_phys}" "${patch_dir_phys}" ||
 347      dirs_contained "${old_dir_phys}" "${new_dir_phys}" ||
 348      dirs_contained "${patch_dir_phys}" "${new_dir_phys}"; then
 349     err "directories must not contain one another"
 350     usage
 351     exit 6
 352   fi
 353
 354   g_cleanup+=("${new_dir}")
 355
 356   patch_dir "${old_dir}" "${patch_dir}" "${new_dir}"
 357
 358   unset g_cleanup[${#g_cleanup[@]}]
 359   trap - EXIT
 360 }
 361
 362 if [[ ${#} -ne 3 ]]; then
 363   usage
 364   exit 2
 365 fi
 366
 367 main "${@}"
 368 exit ${?}