rebar3/bootstrap/bootstrap

#!/usr/bin/env escript
%% -*- mode: erlang;erlang-indent-level: 4;indent-tabs-mode: nil -*-
%% ex: ft=erlang ts=4 sw=4 et

main(Args) ->
    case lists:member("--help", Args) of
        true ->
            usage(),
            halt(0);
        false ->
            ok
    end,

    %% Check for force=1 flag to force a rebuild
    case lists:member("force=1", Args) of
        true ->
            rm("ebin/*.beam");
        false ->
            rm("ebin/rebar.beam")
    end,

    %% Extract the system info of the version of OTP we use to compile rebar

    os:cmd("./bootstrap/rebar get-deps compile escriptize"),

    %% Finally, update executable perms for our script on *nix,
    %%  or write out script files on win32.
    case os:type() of
        {unix,_} ->
            [] = os:cmd("chmod u+x rebar3"),
            ok;
        {win32,_} ->
            write_windows_scripts(),
            ok;
        _ ->
            ok
    end,

    %% Add a helpful message
    io:format("Congratulations! You now have a self-contained script called"
              " \"rebar3\" in\n"
              "your current working directory. "
              "Place this script anywhere in your path\n"
              "and you can use rebar to build OTP-compliant apps.\n").

usage() ->
  io:format("Usage: bootstrap [OPTION]...~n"),
  io:format("    force=1   unconditional build~n"),
  io:format("    debug     add debug information~n").

rm(Path) ->
    NativePath = filename:nativename(Path),
    Cmd = case os:type() of
              {unix,_} -> "rm -f ";
              {win32,_} -> "del /q "
          end,
    [] = os:cmd(Cmd ++ NativePath),
    ok.

write_windows_scripts() ->
    CmdScript=
        "@echo off\r\n"
        "setlocal\r\n"
        "set rebarscript=%~f0\r\n"
        "escript.exe \"%rebarscript:.cmd=%\" %*\r\n",
    ok = file:write_file("rebar.cmd", CmdScript).