portage/tools/generate-stage2-prebuilts

#!/bin/bash
#
# Copyright 2023 The ChromiumOS Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
#
# Copies the existing binpkgs out of the bazel root and generates a
# prebuilts.bazelrc that points to those packages. This allows us to avoid
# having to rebuild all packages when something primordial changes.

set -eu -o pipefail

: "${BOARD?}"
: "${BINPKG_CACHE:=${HOME}/.cache/binpkgs}"

mkdir -p "${BINPKG_CACHE}"

WORKSPACE_ROOT="$(bazel info workspace 2>/dev/null)"
BAZEL_BIN="$(bazel info bazel-bin  2>/dev/null)"
PORTAGE_BIN="${BAZEL_BIN}/external/_main~portage~portage"

PREBUILTS="${WORKSPACE_ROOT}/prebuilts.bazelrc"

exec 3> "${PREBUILTS}.tmp"

declare -A QUERY_MAP=(
    ["prebuilts/stage2-sdk"]="deps(@portage//internal/sdk/stage2)"
    ["prebuilts/stage2-board-sdk"]="deps(@portage//internal/sdk/stage2/target/board)"
    ["prebuilts/stage2-${BOARD}"]="deps(
        @portage//internal/packages/stage2/target/board/chromiumos/virtual/target-os-dev:1_package_set +
        @portage//internal/packages/stage2/target/board/chromiumos/virtual/target-os-factory-shim:1_package_set +
        @portage//internal/packages/stage2/target/board/chromiumos/virtual/target-os-factory:1_package_set +
        @portage//internal/packages/stage2/target/board/chromiumos/virtual/target-os-test:1_package_set +
        @portage//internal/packages/stage2/target/board/chromiumos/virtual/target-os:1_package_set
    )"
)

echo "# Generated using BOARD='${BOARD}' $*" >&3

declare -A SRC_DEST_MAP

for KEY in "${!QUERY_MAP[@]}"
do
    QUERY="${QUERY_MAP["${KEY}"]}"

    readarray -t EBUILD_TARGETS < <(
        set -x
        bazel query --repo_env=_CACHE_BUST_DATE=none "kind(ebuild, ${QUERY})" || kill "$$"
    )

    echo "common:${KEY} \\" >&3
    for TARGET in "${EBUILD_TARGETS[@]}"; do
        TARGET="${TARGET#@portage//}"
        TARGET_DIR="${TARGET%:*}"
        TARGET_NAME="$(basename "${TARGET_DIR}")"
        TARGET_VERSION="${TARGET#*:}"

        BINPKG_NAME="${TARGET_NAME}-${TARGET_VERSION}.tbz2"
        BINPKG_SRC="${PORTAGE_BIN}/${TARGET_DIR}/${BINPKG_NAME}"

        if [[ ! -f "${BINPKG_SRC}" ]]; then
            continue
        fi

        BINPKG_DEST_DIR="${BINPKG_CACHE}/${TARGET_DIR}"
        # Keep the target packages separated
        BINPKG_DEST_DIR="${BINPKG_DEST_DIR/target\/board/"target/${BOARD}"}"
        mkdir -p "${BINPKG_DEST_DIR}"
        BINPKG_DEST="${BINPKG_DEST_DIR}/${BINPKG_NAME}"

        SRC_DEST_MAP["${BINPKG_SRC}"]="${BINPKG_DEST}"

        echo "--@portage//${TARGET}_prebuilt=${BINPKG_DEST} \\" >&3
    done

    # Needed so we don't gobble up the next line
    echo "" >&3
done

echo "Copying packages to ${BINPKG_CACHE}" >&2
for SRC in "${!SRC_DEST_MAP[@]}"; do
    DEST="${SRC_DEST_MAP["${SRC}"]}"
    rsync --progress "${SRC}" "${DEST}" >&2
done

exec 3>&- #close fd 3.
mv "${PREBUILTS}.tmp" "${PREBUILTS}"

echo
echo "${PREBUILTS} was generated" >&2

if ! grep -q prebuilts.bazelrc "${WORKSPACE_ROOT}/workspace.bazelrc"; then
    echo "Adding prebuilts.bazelrc to workspace.bazelrc" >&2
    echo "try-import %workspace%/prebuilts.bazelrc" >>"${WORKSPACE_ROOT}/workspace.bazelrc"
fi

echo "You can now add any of the following to your \`bazel build\` command line:" >&2
for KEY in "${!QUERY_MAP[@]}"
do
    echo "  --config=${KEY}" >&2
done