scripts: Add simplified AOSP merger

Usage: ./lineage/scripts/aosp-merger/aosp-merger.sh [merge|rebase] <oldaosptag> <newaosptag>

Change-Id: I6663e51ee22d7ea262ef634ed5e33c189ee1c2d6

5 files changed, 308 insertions, 0 deletions

diff --git a/aosp-merger/README.md b/aosp-merger/README.md
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+# Rough workflow
+
+1. Snapshot the names of your current working branches to `branches.list` file:
+
+       ./lineage/scripts/aosp-merge/branches_save.sh
+
+2. Note current aosp tag in `.repo/manifests/default.xml`, update it to desired new tag and then create a local commit for the change (aosp-merge script checks for any uncommitted changes in the `.repo/manifests` git repo).
+3. Create a staging branch and merge in the new AOSP tag:
+
+       ./lineage/scripts/aosp-merge/aosp-merge.sh merge \<oldaosptag> \<newaosptag>
+   (where oldaosptag is the original AOSP tag that was in `.repo/manifests/default.xml`)
+   * Example invocation:
+
+         ./lineage/scripts/aosp-merge/aosp-merge.sh merge android-8.0.0_r3 android-8.0.0_r30
+
+4. Every project in your tree should now be one of:
+   * \<newaosptag> if the project was tracking AOSP
+   * a staging branch if the project was a LineageOS fork from AOSP (check `merged_repos.txt` for status and whether there are conflicts to resolve)
+   * the default repo lineage branch for `.repo/manifests/snippets.xml` projects
+5. Restore your local branches and merge in the staging branch:
+
+       ./lineage/scripts/aosp-merge/branches_rebase.sh \<nameofstagingbranch>
+   * Example invocation:
+
+         ./lineage/scripts/aosp-merge/branches_rebase.sh staging/lineage-15.0_merge-android-8.0.0_r30
+6. Build, install, boot, verify, etc.
+
+# TODO
+
+* Make it work for rebase (I'm sure it'll need fixups).
+* Create squashed gerrits for each merge.
+* Abandon squashed gerrits and push each merge automatically.
+* DONE. Instead of merging the staging branch into your local branch (if you have one), create a new branch for the local+staging merge.
diff --git a/aosp-merger/aosp-merger.sh b/aosp-merger/aosp-merger.sh
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+#!/bin/bash
+#
+# Copyright (C) 2017 The LineageOS Project
+#
+# 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.
+#
+
+usage() {
+    echo "Usage ${0} <merge|rebase> <oldaosptag> <newaosptag>"
+}
+
+# Verify argument count
+if [ "$#" -ne 3 ]; then
+    usage
+    exit 1
+fi
+
+OPERATION="${1}"
+OLDTAG="${2}"
+NEWTAG="${3}"
+
+if [ "${OPERATION}" != "merge" -a "${OPERATION}" != "rebase" ]; then
+    usage
+    exit 1
+fi
+
+# Check to make sure this is being run from the top level repo dir
+if [ ! -e "build/envsetup.sh" ]; then
+    echo "Must be run from the top level repo dir"
+    exit 1
+fi
+
+# Source build environment (needed for aospremote)
+. build/envsetup.sh
+
+TOP="${ANDROID_BUILD_TOP}"
+MERGEDREPOS="${TOP}/merged_repos.txt"
+MANIFEST="${TOP}/.repo/manifest.xml"
+BRANCH=$(grep "default revision" "${MANIFEST}" \
+        | sed 's/^ *//g;s/<default revision=\"refs\/heads\///g;s/\"//g')
+STAGINGBRANCH="staging/${BRANCH}_${OPERATION}-${NEWTAG}"
+
+# Build list of LineageOS forked repos
+PROJECTPATHS=$(grep "name=\"LineageOS/" "${MANIFEST}" | sed -n 's/.*path="\([^"]\+\)".*/\1/p')
+
+echo "#### Old tag = ${OLDTAG} Branch = ${BRANCH} Staging branch = ${STAGINGBRANCH} ####"
+
+# Make sure manifest and forked repos are in a consistent state
+echo "#### Verifying there are no uncommitted changes on LineageOS forked AOSP projects ####"
+for PROJECTPATH in ${PROJECTPATHS} .repo/manifests; do
+    cd "${TOP}/${PROJECTPATH}"
+    if [[ -n "$(git status --porcelain)" ]]; then
+        echo "Path ${PROJECTPATH} has uncommitted changes. Please fix."
+        exit 1
+    fi
+done
+echo "#### Verification complete - no uncommitted changes found ####"
+
+# Remove any existing list of merged repos file
+rm -f "${MERGEDREPOS}"
+
+# Sync and detach from current branches
+repo sync -d
+
+# Ditch any existing staging branches (across all projects)
+repo abandon "${STAGINGBRANCH}"
+
+# Iterate over each forked project
+for PROJECTPATH in ${PROJECTPATHS}; do
+    cd "${TOP}/${PROJECTPATH}"
+    repo start "${STAGINGBRANCH}" .
+    aospremote | grep -v "Remote 'aosp' created"
+    git fetch -q --tags aosp "${NEWTAG}"
+
+    PROJECTOPERATION="${OPERATION}"
+
+    # Check if we've actually changed anything before attempting to merge
+    # If we haven't, just "git reset --hard" to the tag
+    if [[ -z "$(git diff HEAD ${OLDTAG})" ]]; then
+        git reset --hard "${NEWTAG}"
+        echo -e "reset\t\t${PROJECTPATH}" | tee -a "${MERGEDREPOS}"
+        continue
+    fi
+
+    # Was there any change upstream? Skip if not.
+    if [[ -z "$(git diff ${OLDTAG} ${NEWTAG})" ]]; then
+        echo -e "nochange\t\t${PROJECTPATH}" | tee -a "${MERGEDREPOS}"
+        continue
+    fi
+
+    # Determine whether OLDTAG is an ancestor of NEWTAG
+    # ie is history consistent.
+    git merge-base --is-ancestor "${OLDTAG}" "${NEWTAG}"
+    # If no, force rebase.
+    if [[ "$?" -eq 1 ]]; then
+        echo -n "#### Project ${PROJECTPATH} old tag ${OLD} is not an ancestor "
+        echo    "of new tag ${NEWTAG}, forcing rebase ####"
+        PROJECTOPERATION="rebase"
+    fi
+
+    if [[ "${PROJECTOPERATION}" == "merge" ]]; then
+        echo "#### Merging ${NEWTAG} into ${PROJECTPATH} ####"
+        git merge --no-edit --log "${NEWTAG}"
+    elif [[ "${PROJECTOPERATION}" == "rebase" ]]; then
+        echo "#### Rebasing ${PROJECTPATH} onto ${NEWTAG} ####"
+        git rebase --onto "${NEWTAG}" "${OLDTAG}"
+    fi
+
+    CONFLICT=""
+    if [[ -n "$(git status --porcelain)" ]]; then
+        CONFLICT="conflict-"
+    fi
+    echo -e "${CONFLICT}${PROJECTOPERATION}\t\t${PROJECTPATH}" | tee -a "${MERGEDREPOS}"
+done
diff --git a/aosp-merger/branches_rebase.sh b/aosp-merger/branches_rebase.sh
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+#!/bin/bash
+#
+# Copyright (C) 2017 The LineageOS Project
+#
+# 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.
+#
+#####
+# Rebase your local working branches onto a new "upstream" branch.
+# Local branch list is defined in branches.list
+# (and can be created with branches_save.sh)
+# If the upstream branch doesn't exist (eg perhaps in lineage-sdk),
+# simply switch the working branch instead.
+
+if [ ! -e "build/envsetup.sh" ]; then
+    echo "Must run from root of repo"
+    exit 1
+fi
+
+if [ "$#" -ne 1 ]; then
+    echo "Usage ${0} <branch to rebase on top of>"
+    exit 1
+fi
+REBASEONTO="${1}"
+
+TOP="${PWD}"
+BRANCHLIST="${TOP}/branches.list"
+
+cat "${BRANCHLIST}" | while read l; do
+    set ${l}
+    PROJECTPATH="${1}"
+    BRANCH="${2}"
+    NEWBRANCH="${2}-rebase"
+    cd "${TOP}/${PROJECTPATH}"
+
+    # Sanity check
+    [[ -n "$(git status --porcelain)" ]]; then
+        echo -n "!!!! Project ${PROJECTPATH} has uncommitted files, "
+        echo    "not switching to branch ${BRANCH} (skipping) !!!!"
+        continue
+    fi
+
+    # Check the $REBASEONTO branch actually exists
+    git show-ref "refs/heads/${REBASEONTO}" >/dev/null
+    if [ "$?" -ne 0 ]; then
+        # Nope
+        echo -n "#### Project ${PROJECTPATH} branch ${REBASEONTO} does not exist, "
+        echo    "switching to ${BRANCH} instead ####"
+        git checkout "${BRANCH}"
+    else
+        echo "#### Creating ${PROJECTPATH} branch ${NEWBRANCH} from ${BRANCH} ####"
+        repo abandon "${NEWBRANCH}" .
+        repo start "${NEWBRANCH}" .
+        git reset --hard "${BRANCH}"
+        echo -n "#### Project ${PROJECTPATH} Rebasing branch ${NEWBRANCH} "
+        echo    "on top of ${REBASEONTO} ####"
+        git rebase --onto "${REBASEONTO}"
+    fi
+done
diff --git a/aosp-merger/branches_restore.sh b/aosp-merger/branches_restore.sh
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+#!/bin/bash
+#
+# Copyright (C) 2017 The LineageOS Project
+#
+# 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.
+#
+
+if [ ! -e "build/envsetup.sh" ]; then
+    echo "Must run from root of repo"
+    exit 1
+fi
+
+TOP="${PWD}"
+BRANCHLIST="${TOP}/branches.list"
+
+cat "${BRANCHLIST}" | while read l; do
+    set ${l}
+    PROJECTPATH="${1}"
+    BRANCH="${2}"
+    cd "${TOP}/${PROJECTPATH}"
+
+    # Check if we're on this branch already
+    CURBRANCH=$(git status -b --porcelain | head -1 | awk '{print $2}' | sed 's/\.\.\..*//')
+    if [ "${CURBRANCH}" == "${BRANCH}" ]; then
+        echo "#### Project ${PROJECTPATH} is already on branch ${BRANCH} ####"
+        continue
+    fi
+
+    # Sanity check
+    if [[ -n "$(git status --porcelain)" ]]; then
+        echo -n "#!#! Project ${PROJECTPATH} has uncommitted files, "
+        echo    "not switching to branch ${BRANCH} #!#!"
+        exit 1
+    fi
+
+    echo "#### Project ${PROJECTPATH} Switching to branch ${BRANCH} ####"
+    git checkout "${BRANCH}"
+done
diff --git a/aosp-merger/branches_save.sh b/aosp-merger/branches_save.sh
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+#!/bin/bash
+#
+# Copyright (C) 2017 The LineageOS Project
+#
+# 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.
+#
+
+if [ ! -e "build/envsetup.sh" ]; then
+    echo "Must run from root of repo"
+    exit 1
+fi
+
+TOP="${PWD}"
+BRANCHLIST="${TOP}/branches.list"
+
+# Example repo status output:
+#project build/make/                             branch x
+#project device/huawei/angler/                   branch x
+
+repo status | grep '^project ' | while read l; do
+    set ${l}
+    PROJECTPATH=$(echo ${2} | sed 's|/$||')
+    BRANCH="${4}"
+    echo "${PROJECTPATH} ${BRANCH}"
+done | sort > "${BRANCHLIST}"