nixpkgs/pkgs/build-support/fetchgit/nix-prefetch-git
Bjørn Forsman 06f5651ef5 nix-prefetch-git: print commit date (close #6522)
The commit date can be used as a version number in packages that don't
have proper releases.
2015-02-24 23:02:59 +01:00

324 lines
8.6 KiB
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Executable File

#! /bin/sh -e
url=
rev=
expHash=
hashType=$NIX_HASH_ALGO
deepClone=$NIX_PREFETCH_GIT_DEEP_CLONE
leaveDotGit=$NIX_PREFETCH_GIT_LEAVE_DOT_GIT
fetchSubmodules=
builder=
if test -n "$deepClone"; then
deepClone=true
else
deepClone=false
fi
if test "$leaveDotGit" != 1; then
leaveDotGit=
else
leaveDotGit=true
fi
argi=0
argfun=""
for arg; do
if test -z "$argfun"; then
case $arg in
--out) argfun=set_out;;
--url) argfun=set_url;;
--rev) argfun=set_rev;;
--hash) argfun=set_hashType;;
--deepClone) deepClone=true;;
--no-deepClone) deepClone=false;;
--leave-dotGit) leaveDotGit=true;;
--fetch-submodules) fetchSubmodules=true;;
--builder) builder=true;;
*)
argi=$(($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
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 submodules recursively.
--no-deepClone Do not clone submodules.
--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
}
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 ${builder:+--progress} origin || return 1
git checkout -b fetchgit $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 fetchgit 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 loose 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/fetchgit) | 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 "$gitdir/..")"
done
fi
}
if test -n "$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