#! /usr/bin/env bash set -e -o pipefail url= rev= expHash= hashType=$NIX_HASH_ALGO deepClone=$NIX_PREFETCH_GIT_DEEP_CLONE leaveDotGit=$NIX_PREFETCH_GIT_LEAVE_DOT_GIT fetchSubmodules= builder= branchName=$NIX_PREFETCH_GIT_BRANCH_NAME if test -n "$deepClone"; then deepClone=true else deepClone=false fi if test "$leaveDotGit" != 1; then leaveDotGit= else leaveDotGit=true fi usage(){ echo >&2 "syntax: nix-prefetch-git [options] [URL [REVISION [EXPECTED-HASH]]] Options: --out path Path where the output would be stored. --url url Any url understand by 'git clone'. --rev ref Any sha1 or references (such as refs/heads/master) --hash h Expected hash. --deepClone Clone the entire repository. --no-deepClone Make a shallow clone of just the required ref. --leave-dotGit Keep the .git directories. --fetch-submodules Fetch submodules. --builder Clone as fetchgit does, but url, rev, and out option are mandatory. " exit 1 } argi=0 argfun="" for arg; do if test -z "$argfun"; then case $arg in --out) argfun=set_out;; --url) argfun=set_url;; --rev) argfun=set_rev;; --hash) argfun=set_hashType;; --branch-name) argfun=set_branchName;; --deepClone) deepClone=true;; --no-deepClone) deepClone=false;; --leave-dotGit) leaveDotGit=true;; --fetch-submodules) fetchSubmodules=true;; --builder) builder=true;; --help) usage; exit;; *) argi=$(($argi + 1)) case $argi in 1) url=$arg;; 2) rev=$arg;; 3) expHash=$arg;; *) exit 1;; esac ;; esac else case $argfun in set_*) var=$(echo $argfun | sed 's,^set_,,') eval $var=$arg ;; esac argfun="" fi done if test -z "$url"; then usage fi init_remote(){ local url=$1 git init git remote add origin $url ( [ -n "$http_proxy" ] && git config http.proxy $http_proxy ) || true } # Return the reference of an hash if it exists on the remote repository. ref_from_hash(){ local hash=$1 git ls-remote origin | sed -n "\,$hash\t, { s,\(.*\)\t\(.*\),\2,; p; q}" } # Return the hash of a reference if it exists on the remote repository. hash_from_ref(){ local ref=$1 git ls-remote origin | sed -n "\,\t$ref, { s,\(.*\)\t\(.*\),\1,; p; q}" } # Fetch everything and checkout the right sha1 checkout_hash(){ local hash="$1" local ref="$2" if test -z "$hash"; then hash=$(hash_from_ref $ref) fi git fetch -t ${builder:+--progress} origin || return 1 git checkout -b $branchName $hash || return 1 } # Fetch only a branch/tag and checkout it. checkout_ref(){ local hash="$1" local ref="$2" if "$deepClone"; then # The caller explicitly asked for a deep clone. Deep clones # allow "git describe" and similar tools to work. See # http://thread.gmane.org/gmane.linux.distributions.nixos/3569 # for a discussion. return 1 fi if test -z "$ref"; then ref=$(ref_from_hash $hash) fi if test -n "$ref"; then # --depth option is ignored on http repository. git fetch ${builder:+--progress} --depth 1 origin +"$ref" || return 1 git checkout -b $branchName FETCH_HEAD || return 1 else return 1 fi } # Update submodules init_submodules(){ # Add urls into .git/config file git submodule init # list submodule directories and their hashes git submodule status | while read l; do # checkout each submodule local hash=$(echo $l | awk '{print substr($1,2)}') local dir=$(echo $l | awk '{print $2}') local name=$( git config -f .gitmodules --get-regexp submodule\..*\.path | sed -n "s,^\(.*\)\.path $dir\$,\\1,p") local url=$(git config --get ${name}.url) clone "$dir" "$url" "$hash" "" done } clone(){ local top=$(pwd) local dir="$1" local url="$2" local hash="$3" local ref="$4" cd $dir # Initialize the repository. init_remote "$url" # Download data from the repository. checkout_ref "$hash" "$ref" || checkout_hash "$hash" "$ref" || ( echo 1>&2 "Unable to checkout $hash$ref from $url." exit 1 ) # Checkout linked sources. if test -n "$fetchSubmodules"; then init_submodules fi if [ -z "$builder" -a -f .topdeps ]; then if tg help 2>&1 > /dev/null then echo "populating TopGit branches..." tg remote --populate origin else echo "WARNING: would populate TopGit branches but TopGit is not available" >&2 echo "WARNING: install TopGit to fix the problem" >&2 fi fi cd $top } # Remove all remote branches, remove tags not reachable from HEAD, do a full # repack and then garbage collect unreferenced objects. make_deterministic_repo(){ local repo="$1" # run in sub-shell to not touch current working directory ( cd "$repo" # Remove files that contain timestamps or otherwise have non-deterministic # properties. rm -rf .git/logs/ .git/hooks/ .git/index .git/FETCH_HEAD .git/ORIG_HEAD \ .git/refs/remotes/origin/HEAD .git/config # Remove all remote branches. git branch -r | while read branch; do git branch -rD "$branch" >&2 done # Remove tags not reachable from HEAD. If we're exactly on a tag, don't # delete it. maybe_tag=$(git tag --points-at HEAD) git tag --contains HEAD | while read tag; do if [ "$tag" != "$maybe_tag" ]; then git tag -d "$tag" >&2 fi done # Do a full repack. Must run single-threaded, or else we lose determinism. git config pack.threads 1 git repack -A -d -f rm -f .git/config # Garbage collect unreferenced objects. git gc --prune=all ) } clone_user_rev() { local dir="$1" local url="$2" local rev="${3:-HEAD}" # Perform the checkout. case "$rev" in HEAD|refs/*) clone "$dir" "$url" "" "$rev" 1>&2;; *) if test -z "$(echo $rev | tr -d 0123456789abcdef)"; then clone "$dir" "$url" "$rev" "" 1>&2 else echo 1>&2 "Bad commit hash or bad reference." exit 1 fi;; esac local full_revision=$(cd $dir && (git rev-parse $rev 2> /dev/null || git rev-parse refs/heads/$branchName) | tail -n1) echo "git revision is $full_revision" echo "git human-readable version is $(cd $dir && (git describe $full_revision 2> /dev/null || git describe --tags $full_revision 2> /dev/null || echo -- none --))" >&2 echo "Commit date is $(cd $dir && git show --no-patch --pretty=%ci $full_revision)" # Allow doing additional processing before .git removal eval "$NIX_PREFETCH_GIT_CHECKOUT_HOOK" if test -z "$leaveDotGit"; then echo "removing \`.git'..." >&2 find $dir -name .git\* | xargs rm -rf else find $dir -name .git | while read gitdir; do make_deterministic_repo "$(readlink -f "$gitdir/..")" done fi } if test -z "$branchName"; then branchName=fetchgit fi if test -n "$builder"; then test -n "$out" -a -n "$url" -a -n "$rev" || usage mkdir $out clone_user_rev "$out" "$url" "$rev" else if test -z "$hashType"; then hashType=sha256 fi # If the hash was given, a file with that hash may already be in the # store. if test -n "$expHash"; then finalPath=$(nix-store --print-fixed-path --recursive "$hashType" "$expHash" git-export) if ! nix-store --check-validity "$finalPath" 2> /dev/null; then finalPath= fi hash=$expHash fi # If we don't know the hash or a path with that hash doesn't exist, # download the file and add it to the store. if test -z "$finalPath"; then tmpPath="$(mktemp -d "${TMPDIR:-/tmp}/git-checkout-tmp-XXXXXXXX")" trap "rm -rf \"$tmpPath\"" EXIT tmpFile="$tmpPath/git-export" mkdir "$tmpFile" # Perform the checkout. clone_user_rev "$tmpFile" "$url" "$rev" # Compute the hash. hash=$(nix-hash --type $hashType $hashFormat $tmpFile) if ! test -n "$QUIET"; then echo "hash is $hash" >&2; fi # Add the downloaded file to the Nix store. finalPath=$(nix-store --add-fixed --recursive "$hashType" $tmpFile) if test -n "$expHash" -a "$expHash" != "$hash"; then echo "hash mismatch for URL \`$url'" exit 1 fi fi if ! test -n "$QUIET"; then echo "path is $finalPath" >&2; fi echo $hash if test -n "$PRINT_PATH"; then echo $finalPath fi fi