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Diffstat (limited to 'contrib/subtree/git-subtree.sh')
| -rwxr-xr-x | contrib/subtree/git-subtree.sh | 901 |
1 files changed, 901 insertions, 0 deletions
diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh new file mode 100755 index 000000000000..868e18b9a1ab --- /dev/null +++ b/contrib/subtree/git-subtree.sh @@ -0,0 +1,901 @@ +#!/bin/sh +# +# git-subtree.sh: split/join git repositories in subdirectories of this one +# +# Copyright (C) 2009 Avery Pennarun <apenwarr@gmail.com> +# +if test $# -eq 0 +then + set -- -h +fi +OPTS_SPEC="\ +git subtree add --prefix=<prefix> <commit> +git subtree add --prefix=<prefix> <repository> <ref> +git subtree merge --prefix=<prefix> <commit> +git subtree pull --prefix=<prefix> <repository> <ref> +git subtree push --prefix=<prefix> <repository> <ref> +git subtree split --prefix=<prefix> <commit> +-- +h,help show the help +q quiet +d show debug messages +P,prefix= the name of the subdir to split out +m,message= use the given message as the commit message for the merge commit + options for 'split' +annotate= add a prefix to commit message of new commits +b,branch= create a new branch from the split subtree +ignore-joins ignore prior --rejoin commits +onto= try connecting new tree to an existing one +rejoin merge the new branch back into HEAD + options for 'add', 'merge', and 'pull' +squash merge subtree changes as a single commit +" +eval "$(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)" + +PATH=$PATH:$(git --exec-path) +. git-sh-setup + +require_work_tree + +quiet= +branch= +debug= +command= +onto= +rejoin= +ignore_joins= +annotate= +squash= +message= +prefix= + +debug () { + if test -n "$debug" + then + printf "%s\n" "$*" >&2 + fi +} + +say () { + if test -z "$quiet" + then + printf "%s\n" "$*" >&2 + fi +} + +progress () { + if test -z "$quiet" + then + printf "%s\r" "$*" >&2 + fi +} + +assert () { + if ! "$@" + then + die "assertion failed: " "$@" + fi +} + +ensure_single_rev () { + if test $# -ne 1 + then + die "You must provide exactly one revision. Got: '$@'" + fi +} + +while test $# -gt 0 +do + opt="$1" + shift + + case "$opt" in + -q) + quiet=1 + ;; + -d) + debug=1 + ;; + --annotate) + annotate="$1" + shift + ;; + --no-annotate) + annotate= + ;; + -b) + branch="$1" + shift + ;; + -P) + prefix="${1%/}" + shift + ;; + -m) + message="$1" + shift + ;; + --no-prefix) + prefix= + ;; + --onto) + onto="$1" + shift + ;; + --no-onto) + onto= + ;; + --rejoin) + rejoin=1 + ;; + --no-rejoin) + rejoin= + ;; + --ignore-joins) + ignore_joins=1 + ;; + --no-ignore-joins) + ignore_joins= + ;; + --squash) + squash=1 + ;; + --no-squash) + squash= + ;; + --) + break + ;; + *) + die "Unexpected option: $opt" + ;; + esac +done + +command="$1" +shift + +case "$command" in +add|merge|pull) + default= + ;; +split|push) + default="--default HEAD" + ;; +*) + die "Unknown command '$command'" + ;; +esac + +if test -z "$prefix" +then + die "You must provide the --prefix option." +fi + +case "$command" in +add) + test -e "$prefix" && + die "prefix '$prefix' already exists." + ;; +*) + test -e "$prefix" || + die "'$prefix' does not exist; use 'git subtree add'" + ;; +esac + +dir="$(dirname "$prefix/.")" + +if test "$command" != "pull" && + test "$command" != "add" && + test "$command" != "push" +then + revs=$(git rev-parse $default --revs-only "$@") || exit $? + dirs=$(git rev-parse --no-revs --no-flags "$@") || exit $? + ensure_single_rev $revs + if test -n "$dirs" + then + die "Error: Use --prefix instead of bare filenames." + fi +fi + +debug "command: {$command}" +debug "quiet: {$quiet}" +debug "revs: {$revs}" +debug "dir: {$dir}" +debug "opts: {$*}" +debug + +cache_setup () { + cachedir="$GIT_DIR/subtree-cache/$$" + rm -rf "$cachedir" || + die "Can't delete old cachedir: $cachedir" + mkdir -p "$cachedir" || + die "Can't create new cachedir: $cachedir" + mkdir -p "$cachedir/notree" || + die "Can't create new cachedir: $cachedir/notree" + debug "Using cachedir: $cachedir" >&2 +} + +cache_get () { + for oldrev in "$@" + do + if test -r "$cachedir/$oldrev" + then + read newrev <"$cachedir/$oldrev" + echo $newrev + fi + done +} + +cache_miss () { + for oldrev in "$@" + do + if ! test -r "$cachedir/$oldrev" + then + echo $oldrev + fi + done +} + +check_parents () { + missed=$(cache_miss "$1") + local indent=$(($2 + 1)) + for miss in $missed + do + if ! test -r "$cachedir/notree/$miss" + then + debug " incorrect order: $miss" + process_split_commit "$miss" "" "$indent" + fi + done +} + +set_notree () { + echo "1" > "$cachedir/notree/$1" +} + +cache_set () { + oldrev="$1" + newrev="$2" + if test "$oldrev" != "latest_old" && + test "$oldrev" != "latest_new" && + test -e "$cachedir/$oldrev" + then + die "cache for $oldrev already exists!" + fi + echo "$newrev" >"$cachedir/$oldrev" +} + +rev_exists () { + if git rev-parse "$1" >/dev/null 2>&1 + then + return 0 + else + return 1 + fi +} + +rev_is_descendant_of_branch () { + newrev="$1" + branch="$2" + branch_hash=$(git rev-parse "$branch") + match=$(git rev-list -1 "$branch_hash" "^$newrev") + + if test -z "$match" + then + return 0 + else + return 1 + fi +} + +# if a commit doesn't have a parent, this might not work. But we only want +# to remove the parent from the rev-list, and since it doesn't exist, it won't +# be there anyway, so do nothing in that case. +try_remove_previous () { + if rev_exists "$1^" + then + echo "^$1^" + fi +} + +find_latest_squash () { + debug "Looking for latest squash ($dir)..." + dir="$1" + sq= + main= + sub= + git log --grep="^git-subtree-dir: $dir/*\$" \ + --no-show-signature --pretty=format:'START %H%n%s%n%n%b%nEND%n' HEAD | + while read a b junk + do + debug "$a $b $junk" + debug "{{$sq/$main/$sub}}" + case "$a" in + START) + sq="$b" + ;; + git-subtree-mainline:) + main="$b" + ;; + git-subtree-split:) + sub="$(git rev-parse "$b^0")" || + die "could not rev-parse split hash $b from commit $sq" + ;; + END) + if test -n "$sub" + then + if test -n "$main" + then + # a rejoin commit? + # Pretend its sub was a squash. + sq="$sub" + fi + debug "Squash found: $sq $sub" + echo "$sq" "$sub" + break + fi + sq= + main= + sub= + ;; + esac + done +} + +find_existing_splits () { + debug "Looking for prior splits..." + dir="$1" + revs="$2" + main= + sub= + local grep_format="^git-subtree-dir: $dir/*\$" + if test -n "$ignore_joins" + then + grep_format="^Add '$dir/' from commit '" + fi + git log --grep="$grep_format" \ + --no-show-signature --pretty=format:'START %H%n%s%n%n%b%nEND%n' $revs | + while read a b junk + do + case "$a" in + START) + sq="$b" + ;; + git-subtree-mainline:) + main="$b" + ;; + git-subtree-split:) + sub="$(git rev-parse "$b^0")" || + die "could not rev-parse split hash $b from commit $sq" + ;; + END) + debug " Main is: '$main'" + if test -z "$main" -a -n "$sub" + then + # squash commits refer to a subtree + debug " Squash: $sq from $sub" + cache_set "$sq" "$sub" + fi + if test -n "$main" -a -n "$sub" + then + debug " Prior: $main -> $sub" + cache_set $main $sub + cache_set $sub $sub + try_remove_previous "$main" + try_remove_previous "$sub" + fi + main= + sub= + ;; + esac + done +} + +copy_commit () { + # We're going to set some environment vars here, so + # do it in a subshell to get rid of them safely later + debug copy_commit "{$1}" "{$2}" "{$3}" + git log -1 --no-show-signature --pretty=format:'%an%n%ae%n%aD%n%cn%n%ce%n%cD%n%B' "$1" | + ( + read GIT_AUTHOR_NAME + read GIT_AUTHOR_EMAIL + read GIT_AUTHOR_DATE + read GIT_COMMITTER_NAME + read GIT_COMMITTER_EMAIL + read GIT_COMMITTER_DATE + export GIT_AUTHOR_NAME \ + GIT_AUTHOR_EMAIL \ + GIT_AUTHOR_DATE \ + GIT_COMMITTER_NAME \ + GIT_COMMITTER_EMAIL \ + GIT_COMMITTER_DATE + ( + printf "%s" "$annotate" + cat + ) | + git commit-tree "$2" $3 # reads the rest of stdin + ) || die "Can't copy commit $1" +} + +add_msg () { + dir="$1" + latest_old="$2" + latest_new="$3" + if test -n "$message" + then + commit_message="$message" + else + commit_message="Add '$dir/' from commit '$latest_new'" + fi + cat <<-EOF + $commit_message + + git-subtree-dir: $dir + git-subtree-mainline: $latest_old + git-subtree-split: $latest_new + EOF +} + +add_squashed_msg () { + if test -n "$message" + then + echo "$message" + else + echo "Merge commit '$1' as '$2'" + fi +} + +rejoin_msg () { + dir="$1" + latest_old="$2" + latest_new="$3" + if test -n "$message" + then + commit_message="$message" + else + commit_message="Split '$dir/' into commit '$latest_new'" + fi + cat <<-EOF + $commit_message + + git-subtree-dir: $dir + git-subtree-mainline: $latest_old + git-subtree-split: $latest_new + EOF +} + +squash_msg () { + dir="$1" + oldsub="$2" + newsub="$3" + newsub_short=$(git rev-parse --short "$newsub") + + if test -n "$oldsub" + then + oldsub_short=$(git rev-parse --short "$oldsub") + echo "Squashed '$dir/' changes from $oldsub_short..$newsub_short" + echo + git log --no-show-signature --pretty=tformat:'%h %s' "$oldsub..$newsub" + git log --no-show-signature --pretty=tformat:'REVERT: %h %s' "$newsub..$oldsub" + else + echo "Squashed '$dir/' content from commit $newsub_short" + fi + + echo + echo "git-subtree-dir: $dir" + echo "git-subtree-split: $newsub" +} + +toptree_for_commit () { + commit="$1" + git rev-parse --verify "$commit^{tree}" || exit $? +} + +subtree_for_commit () { + commit="$1" + dir="$2" + git ls-tree "$commit" -- "$dir" | + while read mode type tree name + do + assert test "$name" = "$dir" + assert test "$type" = "tree" -o "$type" = "commit" + test "$type" = "commit" && continue # ignore submodules + echo $tree + break + done +} + +tree_changed () { + tree=$1 + shift + if test $# -ne 1 + then + return 0 # weird parents, consider it changed + else + ptree=$(toptree_for_commit $1) + if test "$ptree" != "$tree" + then + return 0 # changed + else + return 1 # not changed + fi + fi +} + +new_squash_commit () { + old="$1" + oldsub="$2" + newsub="$3" + tree=$(toptree_for_commit $newsub) || exit $? + if test -n "$old" + then + squash_msg "$dir" "$oldsub" "$newsub" | + git commit-tree "$tree" -p "$old" || exit $? + else + squash_msg "$dir" "" "$newsub" | + git commit-tree "$tree" || exit $? + fi +} + +copy_or_skip () { + rev="$1" + tree="$2" + newparents="$3" + assert test -n "$tree" + + identical= + nonidentical= + p= + gotparents= + copycommit= + for parent in $newparents + do + ptree=$(toptree_for_commit $parent) || exit $? + test -z "$ptree" && continue + if test "$ptree" = "$tree" + then + # an identical parent could be used in place of this rev. + if test -n "$identical" + then + # if a previous identical parent was found, check whether + # one is already an ancestor of the other + mergebase=$(git merge-base $identical $parent) + if test "$identical" = "$mergebase" + then + # current identical commit is an ancestor of parent + identical="$parent" + elif test "$parent" != "$mergebase" + then + # no common history; commit must be copied + copycommit=1 + fi + else + # first identical parent detected + identical="$parent" + fi + else + nonidentical="$parent" + fi + + # sometimes both old parents map to the same newparent; + # eliminate duplicates + is_new=1 + for gp in $gotparents + do + if test "$gp" = "$parent" + then + is_new= + break + fi + done + if test -n "$is_new" + then + gotparents="$gotparents $parent" + p="$p -p $parent" + fi + done + + if test -n "$identical" && test -n "$nonidentical" + then + extras=$(git rev-list --count $identical..$nonidentical) + if test "$extras" -ne 0 + then + # we need to preserve history along the other branch + copycommit=1 + fi + fi + if test -n "$identical" && test -z "$copycommit" + then + echo $identical + else + copy_commit "$rev" "$tree" "$p" || exit $? + fi +} + +ensure_clean () { + if ! git diff-index HEAD --exit-code --quiet 2>&1 + then + die "Working tree has modifications. Cannot add." + fi + if ! git diff-index --cached HEAD --exit-code --quiet 2>&1 + then + die "Index has modifications. Cannot add." + fi +} + +ensure_valid_ref_format () { + git check-ref-format "refs/heads/$1" || + die "'$1' does not look like a ref" +} + +process_split_commit () { + local rev="$1" + local parents="$2" + local indent=$3 + + if test $indent -eq 0 + then + revcount=$(($revcount + 1)) + else + # processing commit without normal parent information; + # fetch from repo + parents=$(git rev-parse "$rev^@") + extracount=$(($extracount + 1)) + fi + + progress "$revcount/$revmax ($createcount) [$extracount]" + + debug "Processing commit: $rev" + exists=$(cache_get "$rev") + if test -n "$exists" + then + debug " prior: $exists" + return + fi + createcount=$(($createcount + 1)) + debug " parents: $parents" + check_parents "$parents" "$indent" + newparents=$(cache_get $parents) + debug " newparents: $newparents" + + tree=$(subtree_for_commit "$rev" "$dir") + debug " tree is: $tree" + + # ugly. is there no better way to tell if this is a subtree + # vs. a mainline commit? Does it matter? + if test -z "$tree" + then + set_notree "$rev" + if test -n "$newparents" + then + cache_set "$rev" "$rev" + fi + return + fi + + newrev=$(copy_or_skip "$rev" "$tree" "$newparents") || exit $? + debug " newrev is: $newrev" + cache_set "$rev" "$newrev" + cache_set latest_new "$newrev" + cache_set latest_old "$rev" +} + +cmd_add () { + if test -e "$dir" + then + die "'$dir' already exists. Cannot add." + fi + + ensure_clean + + if test $# -eq 1 + then + git rev-parse -q --verify "$1^{commit}" >/dev/null || + die "'$1' does not refer to a commit" + + cmd_add_commit "$@" + + elif test $# -eq 2 + then + # Technically we could accept a refspec here but we're + # just going to turn around and add FETCH_HEAD under the + # specified directory. Allowing a refspec might be + # misleading because we won't do anything with any other + # branches fetched via the refspec. + ensure_valid_ref_format "$2" + + cmd_add_repository "$@" + else + say "error: parameters were '$@'" + die "Provide either a commit or a repository and commit." + fi +} + +cmd_add_repository () { + echo "git fetch" "$@" + repository=$1 + refspec=$2 + git fetch "$@" || exit $? + revs=FETCH_HEAD + set -- $revs + cmd_add_commit "$@" +} + +cmd_add_commit () { + rev=$(git rev-parse $default --revs-only "$@") || exit $? + ensure_single_rev $rev + + debug "Adding $dir as '$rev'..." + git read-tree --prefix="$dir" $rev || exit $? + git checkout -- "$dir" || exit $? + tree=$(git write-tree) || exit $? + + headrev=$(git rev-parse HEAD) || exit $? + if test -n "$headrev" && test "$headrev" != "$rev" + then + headp="-p $headrev" + else + headp= + fi + + if test -n "$squash" + then + rev=$(new_squash_commit "" "" "$rev") || exit $? + commit=$(add_squashed_msg "$rev" "$dir" | + git commit-tree "$tree" $headp -p "$rev") || exit $? + else + revp=$(peel_committish "$rev") && + commit=$(add_msg "$dir" $headrev "$rev" | + git commit-tree "$tree" $headp -p "$revp") || exit $? + fi + git reset "$commit" || exit $? + + say "Added dir '$dir'" +} + +cmd_split () { + debug "Splitting $dir..." + cache_setup || exit $? + + if test -n "$onto" + then + debug "Reading history for --onto=$onto..." + git rev-list $onto | + while read rev + do + # the 'onto' history is already just the subdir, so + # any parent we find there can be used verbatim + debug " cache: $rev" + cache_set "$rev" "$rev" + done + fi + + unrevs="$(find_existing_splits "$dir" "$revs")" + + # We can't restrict rev-list to only $dir here, because some of our + # parents have the $dir contents the root, and those won't match. + # (and rev-list --follow doesn't seem to solve this) + grl='git rev-list --topo-order --reverse --parents $revs $unrevs' + revmax=$(eval "$grl" | wc -l) + revcount=0 + createcount=0 + extracount=0 + eval "$grl" | + while read rev parents + do + process_split_commit "$rev" "$parents" 0 + done || exit $? + + latest_new=$(cache_get latest_new) + if test -z "$latest_new" + then + die "No new revisions were found" + fi + + if test -n "$rejoin" + then + debug "Merging split branch into HEAD..." + latest_old=$(cache_get latest_old) + git merge -s ours \ + --allow-unrelated-histories \ + -m "$(rejoin_msg "$dir" "$latest_old" "$latest_new")" \ + "$latest_new" >&2 || exit $? + fi + if test -n "$branch" + then + if rev_exists "refs/heads/$branch" + then + if ! rev_is_descendant_of_branch "$latest_new" "$branch" + then + die "Branch '$branch' is not an ancestor of commit '$latest_new'." + fi + action='Updated' + else + action='Created' + fi + git update-ref -m 'subtree split' \ + "refs/heads/$branch" "$latest_new" || exit $? + say "$action branch '$branch'" + fi + echo "$latest_new" + exit 0 +} + +cmd_merge () { + rev=$(git rev-parse $default --revs-only "$@") || exit $? + ensure_single_rev $rev + ensure_clean + + if test -n "$squash" + then + first_split="$(find_latest_squash "$dir")" + if test -z "$first_split" + then + die "Can't squash-merge: '$dir' was never added." + fi + set $first_split + old=$1 + sub=$2 + if test "$sub" = "$rev" + then + say "Subtree is already at commit $rev." + exit 0 + fi + new=$(new_squash_commit "$old" "$sub" "$rev") || exit $? + debug "New squash commit: $new" + rev="$new" + fi + + version=$(git version) + if test "$version" \< "git version 1.7" + then + if test -n "$message" + then + git merge -s subtree --message="$message" "$rev" + else + git merge -s subtree "$rev" + fi + else + if test -n "$message" + then + git merge -Xsubtree="$prefix" \ + --message="$message" "$rev" + else + git merge -Xsubtree="$prefix" $rev + fi + fi +} + +cmd_pull () { + if test $# -ne 2 + then + die "You must provide <repository> <ref>" + fi + ensure_clean + ensure_valid_ref_format "$2" + git fetch "$@" || exit $? + revs=FETCH_HEAD + set -- $revs + cmd_merge "$@" +} + +cmd_push () { + if test $# -ne 2 + then + die "You must provide <repository> <ref>" + fi + ensure_valid_ref_format "$2" + if test -e "$dir" + then + repository=$1 + refspec=$2 + echo "git push using: " "$repository" "$refspec" + localrev=$(git subtree split --prefix="$prefix") || die + git push "$repository" "$localrev":"refs/heads/$refspec" + else + die "'$dir' must already exist. Try 'git subtree add'." + fi +} + +"cmd_$command" "$@" |