# Params:
#   $1: The URL of the Envoy tar.gz to be downloaded.
#   $2: The full path of the output binary.
#   $3: Non-versioned name to use
function download_envoy_if_necessary () {
  if [[ ! -f "$2" ]] ; then
    # Enter the output directory.
    mkdir -p "$(dirname "$2")"
    pushd "$(dirname "$2")"

    # Download and extract the binary to the output directory.
    echo "Downloading ${SIDECAR}: $1 to $2"

# exec".
# Important: "tfrun foo | bar" is "( tfrun foo ) | bar", not "tfrun (foo | bar)".
# Therefore, "tfrun" commands cannot include pipes -- which is
# probably for the better. If a pipe is necessary for something, it is probably
# complex. Write a well-documented script under utilities/ to encapsulate the
# functionality instead.
tfrun() { "$@"; }

#   $2: The full path of the output binary.
#   $3: Non-versioned name to use
function download_ztunnel_if_necessary () {
  if [[ -f "$2" ]]; then
    return
  fi
  # Enter the output directory.
  mkdir -p "$(dirname "$2")"
  pushd "$(dirname "$2")"

  # Download and make the binary executable
  echo "Downloading ztunnel: $1 to $2"

  rpm2cpio "devtoolset-9-gcc-9.3.1-2.2.el7.src.rpm" |cpio -idmv
  tar -xvf "gcc-9.3.1-20200408.tar.xz" --strip 1
  ;;
devtoolset-10)
  wget --retry-connrefused --waitretry=1 --read-timeout=20 --timeout=15 --tries=5 "https://vault.centos.org/centos/7/sclo/Source/rh/devtoolset-10-gcc-10.2.1-11.2.el7.src.rpm"