honkoma/lib/pleroma/utils.ex

# Pleroma: A lightweight social networking server
# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only

defmodule Pleroma.Utils do
  @posix_error_codes ~w(
    eacces eagain ebadf ebadmsg ebusy edeadlk edeadlock edquot eexist efault
    efbig eftype eintr einval eio eisdir eloop emfile emlink emultihop
    enametoolong enfile enobufs enodev enolck enolink enoent enomem enospc
    enosr enostr enosys enotblk enotdir enotsup enxio eopnotsupp eoverflow
    eperm epipe erange erofs espipe esrch estale etxtbsy exdev
  )a

  def compile_dir(dir) when is_binary(dir) do
    dir
    |> File.ls!()
    |> Enum.map(&Path.join(dir, &1))
    |> Kernel.ParallelCompiler.compile()
  end

  @doc """
  POSIX-compliant check if command is available in the system

  ## Examples
      iex> command_available?("git")
      true
      iex> command_available?("wrongcmd")
      false

  """
  @spec command_available?(String.t()) :: boolean()
  def command_available?(command) do
    match?({_output, 0}, System.cmd("sh", ["-c", "command -v #{command}"]))
  end

  @doc "creates the uniq temporary directory"
  @spec tmp_dir(String.t()) :: {:ok, String.t()} | {:error, :file.posix()}
  def tmp_dir(prefix \\ "") do
    sub_dir =
      [
        prefix,
        Timex.to_unix(Timex.now()),
        :os.getpid(),
        String.downcase(Integer.to_string(:rand.uniform(0x100000000), 36))
      ]
      |> Enum.join("-")

    tmp_dir = Path.join(System.tmp_dir!(), sub_dir)

    case File.mkdir(tmp_dir) do
      :ok -> {:ok, tmp_dir}
      error -> error
    end
  end

  @spec posix_error_message(atom()) :: binary()
  def posix_error_message(code) when code in @posix_error_codes do
    error_message = Gettext.dgettext(Pleroma.Web.Gettext, "posix_errors", "#{code}")
    "(POSIX error: #{error_message})"
  end

  def posix_error_message(_), do: ""
end