hadoop/dev-support/smart-apply-patch.sh

#!/usr/bin/env bash
#   Licensed under the Apache License, Version 2.0 (the "License");
#   you may not use this file except in compliance with the License.
#   You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.

set -e

PATCH_FILE=$1
DRY_RUN=$2
if [ -z "$PATCH_FILE" ]; then
  echo usage: $0 patch-file
  exit 1
fi

PATCH=${PATCH:-patch} # allow overriding patch binary

# Cleanup handler for temporary files
TOCLEAN=""
cleanup() {
  rm $TOCLEAN
  exit $1
}
trap "cleanup 1" HUP INT QUIT TERM

# Allow passing "-" for stdin patches
if [ "$PATCH_FILE" == "-" ]; then
  PATCH_FILE=/tmp/tmp.in.$$
  cat /dev/fd/0 > $PATCH_FILE
  TOCLEAN="$TOCLEAN $PATCH_FILE"
fi

# Was the patch generated by git?  If so, we can definitely use 'git apply' to
# apply it.  This is nice because it allows us to handle binary files.  If
# not, we fall back to applying the patch with "patch", since that's most
# likely what was used to create it.
if git --version &>/dev/null && grep -q -- '^diff --git' "$PATCH_FILE"; then
    PATCH_TYPE="git"
    PATCH_DRY_RUN="git apply --check"
    PATCH_APPLY="git apply"
else
    PATCH_TYPE="non-git"
    PATCH_DRY_RUN="patch --dry-run -E"
    PATCH_APPLY="patch -E"
fi

# Come up with a list of changed files into $TMP
TMP=/tmp/tmp.paths.$$
TOCLEAN="$TOCLEAN $TMP"

# This file contains the error messages from all patch application attempts.
# We only print it when the script fails.
DRY_RUN_ERRORS=/tmp/dry-run-errors.$$
TOCLEAN="$TOCLEAN $DRY_RUN_ERRORS"
touch $DRY_RUN_ERRORS

if $PATCH_DRY_RUN -p0 < $PATCH_FILE 2>>$DRY_RUN_ERRORS 1> $TMP; then
  PLEVEL=0
  #if the patch applied at P0 there is the possability that all we are doing
  # is adding new files and they would apply anywhere. So try to guess the
  # correct place to put those files.

  TMP2=/tmp/tmp.paths.2.$$
  TOCLEAN="$TOCLEAN $TMP2"

  egrep '^patching file |^checking file ' $TMP | awk '{print $3}' | grep -v /dev/null | sort | uniq > $TMP2

  if [ ! -s $TMP2 ]; then
    echo "Error: Patch dryrun couldn't detect changes the patch would make. Exiting."
    cleanup 1
  fi

  #first off check that all of the files do not exist
  FOUND_ANY=0
  for CHECK_FILE in $(cat -- $TMP2)
  do
    if [[ -f $CHECK_FILE ]]; then
      FOUND_ANY=1
    fi
  done

  if [[ "$FOUND_ANY" = "0" ]]; then
    #all of the files are new files so we have to guess where the correct place to put it is.

    # if all of the lines start with a/ or b/, then this is a git patch that
    # was generated without --no-prefix
    if ! grep -qv '^a/\|^b/' $TMP2 ; then
      echo Looks like this is a git patch. Stripping a/ and b/ prefixes
      echo and incrementing PLEVEL
      PLEVEL=$[$PLEVEL + 1]
      sed -i -e 's,^[ab]/,,' $TMP2
    fi

    PREFIX_DIRS_AND_FILES=$(cut -d '/' -f 1 | sort | uniq)

    # if we are at the project root then nothing more to do
    if [[ -d hadoop-common-project ]]; then
      echo Looks like this is being run at project root

    # if all of the lines start with hadoop-common/, hadoop-hdfs/, hadoop-yarn/ or hadoop-mapreduce/, this is
    # relative to the hadoop root instead of the subproject root, so we need
    # to chop off another layer
    elif [[ "$PREFIX_DIRS_AND_FILES" =~ ^(hadoop-common-project|hadoop-hdfs-project|hadoop-yarn-project|hadoop-mapreduce-project)$ ]]; then

      echo Looks like this is relative to project root. Increasing PLEVEL
      PLEVEL=$[$PLEVEL + 1]

    elif ! echo "$PREFIX_DIRS_AND_FILES" | grep -vxq 'hadoop-common-project\|hadoop-hdfs-project\|hadoop-yarn-project\|hadoop-mapreduce-project' ; then
      echo Looks like this is a cross-subproject patch. Try applying from the project root
      cleanup 1
    fi
  fi
elif $PATCH_DRY_RUN -p1 < $PATCH_FILE 2>>$DRY_RUN_ERRORS 1> /dev/null; then
  PLEVEL=1
elif $PATCH_DRY_RUN -p2 < $PATCH_FILE 2>>$DRY_RUN_ERRORS 1> /dev/null; then
  PLEVEL=2
else
  echo "The ${PATCH_TYPE} patch does not appear to apply with p0 to p2.";
  echo
  echo "Dry run errors:"
  cat -- $DRY_RUN_ERRORS
  cleanup 1;
fi

# If this is a dry run then exit instead of applying the patch
if [[ -n $DRY_RUN ]]; then
  cleanup 0;
fi

echo Going to apply ${PATCH_TYPE} patch with: ${PATCH_APPLY} -p$PLEVEL
${PATCH_APPLY} -p$PLEVEL < $PATCH_FILE

cleanup $?