moby--moby/hack/make/dynbinary

#!/bin/bash

DEST=$1

# dockerinit still needs to be a static binary, even if docker is dynamic
CGO_ENABLED=0 go build -o $DEST/dockerinit-$VERSION -ldflags "$LDFLAGS -d" "${BUILDFLAGS[@]}" ./dockerinit
echo "Created binary: $DEST/dockerinit-$VERSION"
ln -sf dockerinit-$VERSION $DEST/dockerinit

sha1sum=
if command -v sha1sum &> /dev/null; then
	sha1sum=sha1sum
elif command -v shasum &> /dev/null; then
	# Mac OS X - why couldn't they just use the same command name and be happy?
	sha1sum=shasum
else
	echo >&2 'error: cannot find sha1sum command or equivalent'
	exit 1
fi

# sha1 our new dockerinit to ensure separate docker and dockerinit always run in a perfect pair compiled for one another
export DOCKER_INITSHA1="$($sha1sum $DEST/dockerinit-$VERSION | cut -d' ' -f1)"
# exported so that "dyntest" can easily access it later without recalculating it

(
	export LDFLAGS_STATIC="-X github.com/dotcloud/docker/dockerversion.INITSHA1 \"$DOCKER_INITSHA1\" -X github.com/dotcloud/docker/dockerversion.INITPATH \"$DOCKER_INITPATH\""
	source "$(dirname "$BASH_SOURCE")/binary"
)