llvm/utils/git/sync-release-repo.sh

   1 #!/bin/bash
   2
   3 # This script will sync github.com/llvm/llvm-project with
   4 # github.com/llvm/llvm-project-release-prs and try to merge
   5 # the changes in the release branch.
   6
   7 set -e
   8 set -x
   9
  10 # We should always get the branch from the environment.
  11 # But otherwise just default to something. We can probably
  12 # have a better default here?
  13 RELEASE_BRANCH="${RELEASE_BRANCH:-release/16.x}"
  14
  15 # We will add two remotes here:
  16 #  main - which will point to the main llvm-project repo
  17 #  release - which will point to the release-prs repo
  18 # The remotes will use random strings to avoid
  19 # collisions
  20 MAIN_REMOTE=$(uuidgen)
  21 RELEASE_REMOTE=$(uuidgen)
  22 CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)
  23
  24 git remote add $MAIN_REMOTE "https://github.com/llvm/llvm-project"
  25 git remote add $RELEASE_REMOTE "https://github.com/llvm/llvm-project-release-prs"
  26
  27 # Make sure we are up to date on all our repos first
  28 git fetch $MAIN_REMOTE
  29 git fetch $RELEASE_REMOTE
  30
  31 # Create our sync branch. Starting with the main
  32 # repo first since it's important to get those
  33 # changes
  34 MERGE_BRANCH=$(uuidgen)
  35 git switch -c $MERGE_BRANCH $MAIN_REMOTE/$RELEASE_BRANCH
  36
  37 # Merge changes from the release repo
  38 git merge --ff-only $RELEASE_REMOTE/$RELEASE_BRANCH
  39
  40 if ! git diff-index --quiet $MAIN_REMOTE/$RELEASE_BRANCH; then
  41   echo "Changes in the release remote - pushing to main remote"
  42   git push $MAIN_REMOTE $MERGE_BRANCH:$RELEASE_BRANCH
  43 fi
  44
  45 # Before we merge back into the release repo
  46 # let's update to make sure nothing has been
  47 # pushed to either repo while we do this work.
  48 # Most of the time this won't do anything, and
  49 # the real solution would instead be to fetch
  50 # in a loop if pushing fails. But that's a very
  51 # tiny edge-case, so let's not complicate this.
  52 git fetch $MAIN_REMOTE
  53 git fetch $RELEASE_REMOTE
  54
  55 # And merge all the new data to the current branch
  56 git merge --ff-only $MAIN_REMOTE/$RELEASE_BRANCH
  57
  58 # If anything changed let's merge it
  59 if ! git diff-index --quiet $RELEASE_REMOTE/$RELEASE_BRANCH; then
  60   echo "Changes in main - pushing to release"
  61   git push $RELEASE_REMOTE $MERGE_BRANCH:$RELEASE_BRANCH
  62 fi
  63
  64 # Cleanup - enable for debug
  65 if false; then
  66   git remote remove $RELEASE_REMOTE
  67   git remote remove $MAIN_REMOTE
  68
  69   git switch $CURRENT_BRANCH
  70   git branch -D $MERGE_BRANCH
  71 fi