|  | # Copyright 2019 The Fuchsia Authors. All rights reserved. | 
|  | # Use of this source code is governed by a BSD-style license that can be | 
|  | # found in the LICENSE file. | 
|  |  | 
|  | case "$(uname -s)" in | 
|  | Linux) | 
|  | readonly HOST_OS="linux" | 
|  | ;; | 
|  | Darwin) | 
|  | readonly HOST_OS="mac" | 
|  | ;; | 
|  | *) | 
|  | echo >&2 "Unknown operating system: $(uname -s)." | 
|  | exit 1 | 
|  | ;; | 
|  | esac | 
|  |  | 
|  | case "$(uname -m)" in | 
|  | x86_64) | 
|  | readonly HOST_CPU="x64" | 
|  | ;; | 
|  | aarch64) | 
|  | readonly HOST_CPU="arm64" | 
|  | ;; | 
|  | *) | 
|  | echo >&2 "Unknown architecture: $(uname -m)." | 
|  | exit 1 | 
|  | ;; | 
|  | esac | 
|  |  | 
|  | readonly HOST_PLATFORM="${HOST_OS}-${HOST_CPU}" | 
|  |  | 
|  | readonly PREBUILT_3P_DIR="${FUCHSIA_DIR}/prebuilt/third_party" | 
|  | readonly PREBUILT_TOOLS_DIR="${FUCHSIA_DIR}/prebuilt/tools" | 
|  |  | 
|  | readonly PREBUILT_AEMU_DIR="${PREBUILT_3P_DIR}/aemu/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_CLANG_DIR="${PREBUILT_3P_DIR}/clang/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_CMAKE_DIR="${PREBUILT_3P_DIR}/cmake/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_DART_DIR="${PREBUILT_3P_DIR}/dart/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_GN="${PREBUILT_3P_DIR}/gn/${HOST_PLATFORM}/gn" | 
|  | readonly PREBUILT_GO_DIR="${PREBUILT_3P_DIR}/go/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_GOMA_DIR="${PREBUILT_3P_DIR}/goma/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_GRPCWEBPROXY_DIR="${PREBUILT_3P_DIR}/grpcwebproxy/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_NINJA="${PREBUILT_3P_DIR}/ninja/${HOST_PLATFORM}/ninja" | 
|  | readonly PREBUILT_PYTHON3_DIR="${PREBUILT_3P_DIR}/python3/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_OVMF_DIR="${PREBUILT_3P_DIR}/ovmf/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_QEMU_DIR="${PREBUILT_3P_DIR}/qemu/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_RUST_DIR="${PREBUILT_3P_DIR}/rust/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_RUST_TOOLS_DIR="${PREBUILT_3P_DIR}/rust_tools/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_CGPT_DIR="${PREBUILT_TOOLS_DIR}/cgpt/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_FUTILITY_DIR="${PREBUILT_TOOLS_DIR}/futility/${HOST_PLATFORM}" | 
|  | readonly PREBUILT_VDL_DIR="${FUCHSIA_DIR}/prebuilt/vdl" |