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path: root/src/rebar_utils.erl
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%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
%% ex: ts=4 sw=4 et
%% -------------------------------------------------------------------
%%
%% rebar: Erlang Build Tools
%%
%% Copyright (c) 2009, 2010 Dave Smith (dizzyd@dizzyd.com)
%%
%% Permission is hereby granted, free of charge, to any person obtaining a copy
%% of this software and associated documentation files (the "Software"), to deal
%% in the Software without restriction, including without limitation the rights
%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
%% copies of the Software, and to permit persons to whom the Software is
%% furnished to do so, subject to the following conditions:
%%
%% The above copyright notice and this permission notice shall be included in
%% all copies or substantial portions of the Software.
%%
%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
%% THE SOFTWARE.
%% -------------------------------------------------------------------
-module(rebar_utils).

-export([sort_deps/1,
         droplast/1,
         filtermap/2,
         is_arch/1,
         sh/2,
         sh_send/3,
         abort/0,
         abort/2,
         escript_foldl/3,
         find_files/2,
         find_files/3,
         find_files_in_dirs/3,
         find_source/3,
         beam_to_mod/1,
         erl_to_mod/1,
         beams/1,
         find_executable/1,
         vcs_vsn/3,
         deprecated/3,
         deprecated/4,
         indent/1,
         update_code/1,
         update_code/2,
         remove_from_code_path/1,
         cleanup_code_path/1,
         args_to_tasks/1,
         expand_env_variable/3,
         get_arch/0,
         wordsize/0,
         deps_to_binary/1,
         to_binary/1,
         to_list/1,
         tup_dedup/1,
         tup_umerge/2,
         tup_sort/1,
         tup_find/2,
         line_count/1,
         set_httpc_options/0,
         url_append_path/2,
         escape_chars/1,
         escape_double_quotes/1,
         escape_double_quotes_weak/1,
         check_min_otp_version/1,
         check_blacklisted_otp_versions/1,
         info_useless/2,
         list_dir/1,
         user_agent/0,
         reread_config/1, reread_config/2,
         get_proxy_auth/0,
         is_list_of_strings/1,
         ssl_opts/1]).


%% for internal use only
-export([otp_release/0]).

-include("rebar.hrl").
-include_lib("public_key/include/OTP-PUB-KEY.hrl").

-define(ONE_LEVEL_INDENT, "     ").
-define(APP_NAME_INDEX, 2).

%% ====================================================================
%% Public API
%% ====================================================================

sort_deps(Deps) ->
    %% We need a sort stable, based on the name. So that for multiple deps on
    %% the same level with the same name, we keep the order the parents had.
    %% `lists:keysort/2' is documented as stable in the stdlib.
    %% The list of deps is revered when we get it. For the proper stable
    %% result, re-reverse it.
    lists:keysort(?APP_NAME_INDEX, lists:reverse(Deps)).

droplast(L) ->
    lists:reverse(tl(lists:reverse(L))).

%% @doc filtermap takes in a function that is either or both
%% a predicate and a map, and returns the matching and valid elements.
-spec filtermap(F, [In]) -> [Out] when
      F :: fun((In) -> boolean() | {true, Out}),
      In :: term(),
      Out :: term().
filtermap(F, [Hd|Tail]) ->
    case F(Hd) of
        true ->
            [Hd|filtermap(F, Tail)];
        {true,Val} ->
            [Val|filtermap(F, Tail)];
        false ->
            filtermap(F, Tail)
    end;
filtermap(F, []) when is_function(F, 1) -> [].

is_arch(ArchRegex) ->
    case re:run(get_arch(), ArchRegex, [{capture, none}, unicode]) of
        match ->
            true;
        nomatch ->
            false
    end.

%% @doc returns the sytem architecture, in strings like
%% `"19.0.4-x86_64-unknown-linux-gnu-64"'.
-spec get_arch() -> string().
get_arch() ->
    Words = wordsize(),
    otp_release() ++ "-"
        ++ erlang:system_info(system_architecture) ++ "-" ++ Words.

%% @doc returns the size of a word on the system, as a string
-spec wordsize() -> string().
wordsize() ->
    try erlang:system_info({wordsize, external}) of
        Val ->
            integer_to_list(8 * Val)
    catch
        error:badarg ->
            integer_to_list(8 * erlang:system_info(wordsize))
    end.

sh_send(Command0, String, Options0) ->
    ?INFO("sh_send info:\n\tcwd: ~p\n\tcmd: ~ts < ~ts\n",
          [rebar_dir:get_cwd(), Command0, String]),
    ?DEBUG("\topts: ~p\n", [Options0]),

    DefaultOptions = [use_stdout, abort_on_error],
    Options = [expand_sh_flag(V)
               || V <- proplists:compact(Options0 ++ DefaultOptions)],

    Command = lists:flatten(patch_on_windows(Command0, proplists:get_value(env, Options, []))),
    PortSettings = proplists:get_all_values(port_settings, Options) ++
        [exit_status, {line, 16384}, use_stdio, stderr_to_stdout, hide],
    Port = open_port({spawn, Command}, PortSettings),
    try
        %% allow us to send some data to the shell command's STDIN
        %% Erlang doesn't let us get any reply after sending an EOF, though...
        Port ! {self(), {command, String}}
    after
        port_close(Port)
    end.

%%
%% Options = [Option] -- defaults to [use_stdout, abort_on_error]
%% Option = ErrorOption | OutputOption | {cd, string()} | {env, Env}
%% ErrorOption = return_on_error | abort_on_error | {abort_on_error, string()}
%% OutputOption = use_stdout | {use_stdout, bool()}
%% Env = [{string(), Val}]
%% Val = string() | false
%%
sh(Command0, Options0) ->
    ?DEBUG("sh info:\n\tcwd: ~p\n\tcmd: ~ts\n", [rebar_dir:get_cwd(), Command0]),
    ?DEBUG("\topts: ~p\n", [Options0]),

    DefaultOptions = [{use_stdout, false}, debug_and_abort_on_error],
    Options = [expand_sh_flag(V)
               || V <- proplists:compact(Options0 ++ DefaultOptions)],

    ErrorHandler = proplists:get_value(error_handler, Options),
    OutputHandler = proplists:get_value(output_handler, Options),

    Command = lists:flatten(patch_on_windows(Command0, proplists:get_value(env, Options, []))),
    PortSettings = proplists:get_all_values(port_settings, Options) ++
        [exit_status, {line, 16384}, use_stdio, stderr_to_stdout, hide, eof],
    ?DEBUG("Port Cmd: ~ts\nPort Opts: ~p\n", [Command, PortSettings]),
    Port = open_port({spawn, Command}, PortSettings),

    try
        case sh_loop(Port, OutputHandler, []) of
            {ok, _Output} = Ok ->
                Ok;
            {error, {_Rc, _Output}=Err} ->
                ErrorHandler(Command, Err)
        end
    after
        port_close(Port)
    end.

find_files(Dir, Regex) ->
    find_files(Dir, Regex, true).

find_files_in_dirs([], _Regex, _Recursive) ->
    [];
find_files_in_dirs([Dir | T], Regex, Recursive) ->
    find_files(Dir, Regex, Recursive) ++ find_files_in_dirs(T, Regex, Recursive).


find_files(Dir, Regex, Recursive) ->
    filelib:fold_files(Dir, Regex, Recursive,
                       fun(F, Acc) -> [F | Acc] end, []).

find_executable(Name) ->
    case os:find_executable(Name) of
        false -> false;
        Path ->
            "\"" ++ filename:nativename(Path) ++ "\""
    end.

deprecated(Old, New, Opts, When) when is_list(Opts) ->
    case lists:member(Old, Opts) of
        true ->
            deprecated(Old, New, When);
        false ->
            ok
    end;
deprecated(Old, New, Config, When) ->
    case rebar_state:get(Config, Old, undefined) of
        undefined ->
            ok;
        _ ->
            deprecated(Old, New, When)
    end.

deprecated(Old, New, When) ->
    io:format(
      <<"WARNING: deprecated ~p option used~n"
        "Option '~p' has been deprecated~n"
        "in favor of '~p'.~n"
        "'~p' will be removed ~ts.~n">>,
      [Old, Old, New, Old, When]).

%% for use by `do` task

%% note: this does not handle the case where you have an argument that
%%  was enclosed in quotes and might have commas but should not be split.
args_to_tasks(Args) -> new_task(Args, []).

deps_to_binary([]) ->
    [];
deps_to_binary([{Name, _, Source} | T]) ->
    [{to_binary(Name), Source} | deps_to_binary(T)];
deps_to_binary([{Name, Source} | T]) ->
    [{to_binary(Name), Source} | deps_to_binary(T)];
deps_to_binary([Name | T]) ->
    [to_binary(Name) | deps_to_binary(T)].

to_binary(A) when is_atom(A) -> atom_to_binary(A, unicode);
to_binary(Str) -> unicode:characters_to_binary(Str).

to_list(A) when is_atom(A) -> atom_to_list(A);
to_list(Str) -> unicode:characters_to_list(Str).

tup_dedup(List) ->
    tup_dedup_(tup_sort(List)).

tup_dedup_([]) ->
    [];
tup_dedup_([A]) ->
    [A];
tup_dedup_([A,B|T]) when element(1, A) =:= element(1, B) ->
    tup_dedup_([A | T]);
tup_dedup_([A,B|T]) when element(1, A) =:= B ->
    tup_dedup_([A | T]);
tup_dedup_([A,B|T]) when A =:= element(1, B) ->
    tup_dedup_([A | T]);
tup_dedup_([A,A|T]) ->
    [A|tup_dedup_(T)];
tup_dedup_([A|T]) ->
    [A|tup_dedup_(T)].

%% Sort the list in proplist-order, meaning that `{a,b}' and `{a,c}'
%% both compare as usual, and `a' and `b' do the same, but `a' and `{a,b}' will
%% compare based on the first element of the key, and in order. So the following
%% list will sort as:
%% - `[native, {native,o3}, check]' -> `[check, native, {native, o3}]'
%% - `[native, {native,o3}, {native, o2}, check]' -> `[check,native,{native,o3},{native,o2}]'
%% Meaning that:
%% a) no deduplication takes place
%% b) the key of a tuple is what counts in being sorted, but atoms are seen as {atom}
%%    as far as comparison is concerned (departing from lists:ukeysort/2)
%% c) order is preserved for similar keys and tuples no matter their size (sort is stable)
%%
%% These properties let us merge proplists fairly easily.
tup_sort(List) ->
    lists:sort(fun(A, B) when is_tuple(A), is_tuple(B) -> element(1, A) =< element(1, B)
               ;  (A, B) when is_tuple(A) -> element(1, A) =< B
               ;  (A, B) when is_tuple(B) -> A =< element(1, B)
               ;  (A, B) -> A =< B
               end, List).

%% Custom merge functions. The objective is to behave like lists:umerge/2,
%% except that we also compare the merge elements based on the key if they're a
%% tuple, such that `{key, val1}' is always prioritized over `{key, val0}' if
%% the former is from the 'new' list.
%%
%% This lets us apply proper overrides to list of elements according to profile
%% priority. This function depends on a stable proplist sort.
tup_umerge(NewList, OldList) ->
    tup_umerge_(tup_sort(NewList), tup_sort(OldList)).

tup_umerge_([], Olds) ->
    Olds;
tup_umerge_([New|News], Olds) ->
    tup_umerge_dedup_(umerge(new, News, Olds, [], New), []).

%% removes 100% identical duplicate elements so that
%% `[a,{a,b},a,{a,c},a]' returns `[a,{a,b},{a,c}]'.
%% Operates on a reverted list that gets reversed as part of this pass
tup_umerge_dedup_([], Acc) ->
    Acc;
tup_umerge_dedup_([H|T], Acc) ->
    case lists:member(H,T) of
        true -> tup_umerge_dedup_(T, Acc);
        false -> tup_umerge_dedup_(T, [H|Acc])
    end.

tup_find(_Elem, []) ->
    false;
tup_find(Elem, [Elem | _Elems]) ->
    Elem;
tup_find(Elem, [Elem1 | Elems]) when is_tuple(Elem1) ->
    case element(1, Elem1) =:= Elem of
        true ->
            Elem1;
        false ->
            tup_find(Elem, Elems)
    end;
tup_find(Elem, [_Elem | Elems]) ->
    tup_find(Elem, Elems).

-spec umerge(new|old, News, Olds, Acc, Current) -> Merged when
      News :: [term()],
      Olds :: [term()],
      Acc  :: [term()],
      Current :: term(),
      Merged :: [term()].
umerge(_, [], [], Acc, Current) ->
    [Current | Acc];
umerge(new, News, [], Acc, Current) ->
    %% only news left
    lists:reverse(News, [Current|Acc]);
umerge(old, [], Olds, Acc, Current) ->
    %% only olds left
    lists:reverse(Olds, [Current|Acc]);
umerge(new, News, [Old|Olds], Acc, Current) ->
    {Dir, Merged, NewCurrent} = compare({new, Current}, {old, Old}),
    umerge(Dir, News, Olds, [Merged|Acc], NewCurrent);
umerge(old, [New|News], Olds, Acc, Current) ->
    {Dir, Merged, NewCurrent} = compare({new, New}, {old, Current}),
    umerge(Dir, News, Olds, [Merged|Acc], NewCurrent).

-spec compare({Priority, term()}, {Secondary, term()}) ->
    {NextPriority, Merged, Larger} when
      Priority :: new | old,
      Secondary :: new | old,
      NextPriority :: new | old,
      Merged :: term(),
      Larger :: term().
compare({Priority, A}, {Secondary, B}) when is_tuple(A), is_tuple(B) ->
    KA = element(1,A),
    KB = element(1,B),
    if KA == KB -> {Secondary, A, B};
       KA  < KB -> {Secondary, A, B};
       KA  > KB -> {Priority, B, A}
    end;
compare({Priority, A}, {Secondary, B}) when not is_tuple(A), not is_tuple(B) ->
    if A == B -> {Secondary, A, B};
       A  < B -> {Secondary, A, B};
       A  > B -> {Priority, B, A}
    end;
compare({Priority, A}, {Secondary, B}) when is_tuple(A), not is_tuple(B) ->
    KA = element(1,A),
    if KA == B -> {Secondary, A, B};
       KA  < B -> {Secondary, A, B};
       KA  > B -> {Priority, B, A}
    end;
compare({Priority, A}, {Secondary, B}) when not is_tuple(A), is_tuple(B) ->
    KB = element(1,B),
    if A == KB -> {Secondary, A, B};
       A  < KB -> {Secondary, A, B};
       A  > KB -> {Priority, B, A}
    end.

%% Implements wc -l functionality used to determine patchcount from git output
line_count(PatchLines) ->
    Tokenized = rebar_string:lexemes(PatchLines, "\n"),
    {ok, length(Tokenized)}.

check_min_otp_version(undefined) ->
    ok;
check_min_otp_version(MinOtpVersion) ->
    %% Fully-qualify with ?MODULE so the function can be meck'd in rebar_utils_SUITE
    OtpRelease = ?MODULE:otp_release(),
    ParsedMin = version_tuple(MinOtpVersion),
    ParsedVsn = version_tuple(OtpRelease),

    case ParsedVsn >= ParsedMin of
        true ->
            ?DEBUG("~ts satisfies the requirement for minimum OTP version ~ts",
                   [OtpRelease, MinOtpVersion]);
        false ->
            ?ABORT("OTP release ~ts or later is required. Version in use: ~ts",
                   [MinOtpVersion, OtpRelease])
    end.

check_blacklisted_otp_versions(undefined) ->
    ok;
check_blacklisted_otp_versions(BlacklistedRegexes) ->
    %% Fully-qualify with ?MODULE so the function can be meck'd in rebar_utils_SUITE
    OtpRelease = ?MODULE:otp_release(),
    lists:foreach(
        fun(BlacklistedRegex) -> abort_if_blacklisted(BlacklistedRegex, OtpRelease) end,
        BlacklistedRegexes).

abort_if_blacklisted(BlacklistedRegex, OtpRelease) ->
    case re:run(OtpRelease, BlacklistedRegex, [{capture, none}]) of
        match ->
            ?ABORT("OTP release ~ts matches blacklisted version ~ts",
                   [OtpRelease, BlacklistedRegex]);
        nomatch ->
            ?DEBUG("~ts does not match blacklisted OTP version ~ts",
                   [OtpRelease, BlacklistedRegex])
    end.

user_agent() ->
    {ok, Vsn} = application:get_key(rebar, vsn),
    ?FMT("Rebar/~ts (OTP/~ts)", [Vsn, otp_release()]).

reread_config(ConfigList) ->
    %% Default to not re-configuring the logger for now;
    %% this can leak logs in CT redirection when setting up hooks
    %% for example. If we want to turn it on by default, we may
    %% want to disable it in CT at the same time or figure out a
    %% way to silence it.
    %% The same pattern may apply to other tasks, so let's enable
    %% case-by-case.
    reread_config(ConfigList, []).

reread_config(ConfigList, Opts) ->
    UpdateLoggerConfig = erlang:function_exported(logger, module_info, 0) andalso
                         proplists:get_value(update_logger, Opts, false),
    %% NB: we attempt to mimic -config here, which survives app reload,
    %% hence {persistent, true}.
    SetEnv = case version_tuple(?MODULE:otp_release()) of
        {X, _, _} when X =< 17 ->
            fun application:set_env/3;
        _ ->
            fun (App, Key, Val) -> application:set_env(App, Key, Val, [{persistent, true}]) end
    end,
    try
        Res =
        [SetEnv(Application, Key, Val)
        || Config <- ConfigList,
           {Application, Items} <- Config,
           {Key, Val} <- Items],
        case UpdateLoggerConfig of
            true -> reread_logger_config();
            false -> ok
        end,
        Res
    catch _:_ ->
            ?ERROR("The configuration file submitted could not be read "
                  "and will be ignored.", [])
    end.

%% @private since the kernel app is already booted, re-reading its config
%% requires doing some magic to dynamically patch running handlers to
%% deal with the current value.
reread_logger_config() ->
    KernelCfg = application:get_all_env(kernel),
    LogCfg = proplists:get_value(logger, KernelCfg),
    case LogCfg of
        undefined ->
            ok;
        _ ->
            %% Extract and apply settings related to primary configuration
            %% -- primary config is used for settings shared across handlers
            LogLvlPrimary = proplists:get_value(logger_info, KernelCfg, all),
            {FilterDefault, Filters} =
              case lists:keyfind(filters, 1, KernelCfg) of
                  false -> {log, []};
                  {filters, FoundDef, FoundFilter} -> {FoundDef, FoundFilter}
              end,
            Primary = #{level => LogLvlPrimary,
                        filter_default => FilterDefault,
                        filters => Filters},
            %% Load the correct handlers based on their individual config.
            [case Id of
                 default -> logger:update_handler_config(Id, Cfg);
                 _ -> logger:add_handler(Id, Mod, Cfg)
             end || {handler, Id, Mod, Cfg} <- LogCfg],
            logger:set_primary_config(Primary),
            ok
    end.


%% @doc Given env. variable `FOO' we want to expand all references to
%% it in `InStr'. References can have two forms: `$FOO' and `${FOO}'
%% The end of form `$FOO' is delimited with whitespace or EOL
-spec expand_env_variable(string(), string(), term()) -> string().
expand_env_variable(InStr, VarName, RawVarValue) ->
    case rebar_string:chr(InStr, $$) of
        0 ->
            %% No variables to expand
            InStr;
        _ ->
            ReOpts = [global, unicode, {return, list}],
            VarValue = re:replace(RawVarValue, "\\\\", "\\\\\\\\", ReOpts),
            %% Use a regex to match/replace:
            %% Given variable "FOO": match $FOO\s | $FOOeol | ${FOO}
            RegEx = io_lib:format("\\\$(~ts(\\W|$)|{~ts})", [VarName, VarName]),
            re:replace(InStr, RegEx, [VarValue, "\\2"], ReOpts)
    end.

%% ====================================================================
%% Internal functions
%% ====================================================================
version_tuple(OtpRelease) ->
    case re:run(OtpRelease, "R?(\\d+)B?.?-?(\\d+)?.?-?(\\d+)?", [{capture, all, list}]) of
        {match, [_Full, Maj, Min, Patch]} ->
            {list_to_integer(Maj), list_to_integer(Min), list_to_integer(Patch)};
        {match, [_Full, Maj, Min]} ->
            {list_to_integer(Maj), list_to_integer(Min), 0};
        {match, [_Full, Maj]} ->
            {list_to_integer(Maj), 0, 0};
        nomatch ->
            ?ABORT("Minimum OTP release unable to be parsed: ~ts", [OtpRelease])
    end.

otp_release() ->
    otp_release1(erlang:system_info(otp_release)).

%% If OTP <= R16, otp_release is already what we want.
otp_release1([$R,N|_]=Rel) when is_integer(N) ->
    Rel;
%% If OTP >= 17.x, erlang:system_info(otp_release) returns just the
%% major version number, we have to read the full version from
%% a file. See http://www.erlang.org/doc/system_principles/versions.html
%% Read vsn string from the 'OTP_VERSION' file and return as list without
%% the "\n".
otp_release1(Rel) ->
    File = filename:join([code:root_dir(), "releases", Rel, "OTP_VERSION"]),
    case file:read_file(File) of
        {error, _} ->
            Rel;
        {ok, Vsn} ->
            %% It's fine to rely on the binary module here because we can
            %% be sure that it's available when the otp_release string does
            %% not begin with $R.
            %% The shortest vsn string consists of at least two digits
            %% followed by "\n". Therefore, it's safe to assume Size >= 3.
            case binary:match(Vsn, <<"**">>) of
                {Pos, _} ->
                    %% The OTP documentation mentions that a system patched
                    %% using the otp_patch_apply tool available to licensed
                    %% customers will leave a '**' suffix in the version as a
                    %% flag saying the system consists of application versions
                    %% from multiple OTP versions. We ignore this flag and
                    %% drop the suffix, given for all intents and purposes, we
                    %% cannot obtain relevant information from it as far as
                    %% tooling is concerned.
                    binary:bin_to_list(Vsn, {0, Pos});
                nomatch ->
                    rebar_string:trim(binary:bin_to_list(Vsn), trailing, "\n")
            end
    end.

%% We do the shell variable substitution ourselves on Windows and hope that the
%% command doesn't use any other shell magic.
patch_on_windows(Cmd, Env) ->
    case os:type() of
        {win32,nt} ->
            Cmd1 = "cmd /q /c "
                ++ lists:foldl(fun({Key, Value}, Acc) ->
                                       expand_env_variable(Acc, Key, Value)
                               end, Cmd, Env),
            %% Remove left-over vars
            re:replace(Cmd1, "\\\$\\w+|\\\${\\w+}", "",
                       [global, {return, list}, unicode]);
        _ ->
            Cmd
    end.

expand_sh_flag(return_on_error) ->
    {error_handler,
     fun(_Command, Err) ->
             {error, Err}
     end};
expand_sh_flag(abort_on_error) ->
    {error_handler,
     fun log_and_abort/2};
expand_sh_flag({abort_on_error, Message}) ->
    {error_handler,
     log_msg_and_abort(Message)};
expand_sh_flag({debug_abort_on_error, Message}) ->
    {error_handler,
     debug_log_msg_and_abort(Message)};
expand_sh_flag(debug_and_abort_on_error) ->
    {error_handler,
     fun debug_and_abort/2};
expand_sh_flag(use_stdout) ->
    {output_handler,
     fun(Line, Acc) ->
             %% Line already has a newline so don't use ?CONSOLE which adds one
             io:format("~ts", [Line]),
             [Line | Acc]
     end};
expand_sh_flag({use_stdout, false}) ->
    {output_handler,
     fun(Line, Acc) ->
             [Line | Acc]
     end};
expand_sh_flag({cd, _CdArg} = Cd) ->
    {port_settings, Cd};
expand_sh_flag({env, _EnvArg} = Env) ->
    {port_settings, Env}.

-type err_handler() :: fun((string(), {integer(), string()}) -> no_return()).
-spec log_msg_and_abort(string()) -> err_handler().
log_msg_and_abort(Message) ->
    fun(_Command, {_Rc, _Output}) ->
            ?ABORT(Message, [])
    end.

-spec debug_log_msg_and_abort(string()) -> err_handler().
debug_log_msg_and_abort(Message) ->
    fun(Command, {Rc, Output}) ->
            ?DEBUG("sh(~ts)~n"
                  "failed with return code ~w and the following output:~n"
                  "~ts", [Command, Rc, Output]),
            ?ABORT(Message, [])
    end.

-spec log_and_abort(string(), {integer(), string()}) -> no_return().
log_and_abort(Command, {Rc, Output}) ->
    ?ABORT("sh(~ts)~n"
          "failed with return code ~w and the following output:~n"
          "~ts", [Command, Rc, Output]).

-spec debug_and_abort(string(), {integer(), string()}) -> no_return().
debug_and_abort(Command, {Rc, Output}) ->
    ?DEBUG("sh(~ts)~n"
          "failed with return code ~w and the following output:~n"
          "~ts", [Command, Rc, Output]),
    throw(rebar_abort).

sh_loop(Port, Fun, Acc) ->
    receive
        {Port, {data, {eol, Line}}} ->
            sh_loop(Port, Fun, Fun(Line ++ "\n", Acc));
        {Port, {data, {noeol, Line}}} ->
            sh_loop(Port, Fun, Fun(Line, Acc));
        {Port, eof} ->
            Data = lists:flatten(lists:reverse(Acc)),
            receive
                {Port, {exit_status, 0}} ->
                    {ok, Data};
                {Port, {exit_status, Rc}} ->
                    {error, {Rc, Data}}
            end
    end.

beam_to_mod(Filename) ->
    list_to_atom(filename:basename(Filename, ".beam")).

erl_to_mod(Filename) ->
    list_to_atom(filename:rootname(filename:basename(Filename))).

beams(Dir) ->
    filelib:wildcard(filename:join(Dir, "*.beam")).

-spec abort() -> no_return().
abort() ->
    throw(rebar_abort).

-spec abort(string(), [term()]) -> no_return().
abort(String, Args) ->
    ?ERROR(String, Args),
    abort().

escript_foldl(Fun, Acc, File) ->
    case escript:extract(File, [compile_source]) of
        {ok, [_Shebang, _Comment, _EmuArgs, Body]} ->
            case Body of
                {source, BeamCode} ->
                    GetInfo = fun() -> file:read_file_info(File) end,
                    GetBin = fun() -> BeamCode end,
                    {ok, Fun(".", GetInfo, GetBin, Acc)};
                {beam, BeamCode} ->
                    GetInfo = fun() -> file:read_file_info(File) end,
                    GetBin = fun() -> BeamCode end,
                    {ok, Fun(".", GetInfo, GetBin, Acc)};
                {archive, ArchiveBin} ->
                    zip:foldl(Fun, Acc, {File, ArchiveBin})
            end;
        {error, _} = Error ->
            Error
    end.

vcs_vsn(AppInfo, Vcs, State) ->
    case vcs_vsn_cmd(AppInfo, Vcs, State) of
        {plain, VsnString} ->
            VsnString;
        {cmd, CmdString} ->
            vcs_vsn_invoke(CmdString, rebar_app_info:dir(AppInfo));
        unknown ->
            ?ABORT("vcs_vsn: Unknown vsn format: ~p", [Vcs]);
        {error, Reason} ->
            ?ABORT("vcs_vsn: ~ts", [Reason])
    end.

%% Temp work around for repos like relx that use "semver"
vcs_vsn_cmd(_AppInfo, Vsn, _) when is_binary(Vsn) ->
    {plain, Vsn};
vcs_vsn_cmd(AppInfo, VCS, State) when VCS =:= semver ; VCS =:= "semver" ->
    vcs_vsn_cmd(AppInfo, git, State);
vcs_vsn_cmd(_AppInfo, {cmd, _Cmd}=Custom, _) ->
    Custom;
vcs_vsn_cmd(AppInfo, VCS, State) when is_atom(VCS) ->
    rebar_resource_v2:make_vsn(AppInfo, VCS, State);
vcs_vsn_cmd(AppInfo, VCS, State) when is_list(VCS) ->
    try list_to_existing_atom(VCS) of
        AVCS ->
            case vcs_vsn_cmd(AppInfo, AVCS, State) of
                unknown -> {plain, VCS};
                Other -> Other
            end
    catch
        error:badarg ->
            {plain, VCS}
    end;
vcs_vsn_cmd(_, _, _) ->
    unknown.

vcs_vsn_invoke(Cmd, Dir) ->
    {ok, VsnString} = rebar_utils:sh(Cmd, [{cd, Dir}, {use_stdout, false}]),
    rebar_string:trim(VsnString, trailing, "\n").

%% @doc ident to the level specified
-spec indent(non_neg_integer()) -> iolist().
indent(Amount) when erlang:is_integer(Amount) ->
    [?ONE_LEVEL_INDENT || _ <- lists:seq(1, Amount)].

%% Replace code paths with new paths for existing apps and
%% purge code of the old modules from those apps.
update_code(Paths) -> update_code(Paths, []).

update_code(Paths, Opts) ->
    lists:foreach(fun(Path) ->
                          Name = filename:basename(Path, "/ebin"),
                          App = list_to_atom(Name),
                          application:load(App),
                          case application:get_key(App, modules) of
                              undefined ->
                                  code:add_patha(Path),
                                  ok;
                              {ok, Modules} ->
                                  %% replace_path causes problems when running
                                  %% tests in projects like erlware_commons that rebar3
                                  %% also includes
                                  %code:replace_path(App, Path),
                                  code:del_path(App),
                                  code:add_patha(Path),
                                  case lists:member(soft_purge, Opts) of
                                      true  ->
                                          [begin code:soft_purge(M), code:delete(M) end || M <- Modules];
                                      false ->
                                          [begin code:purge(M), code:delete(M) end || M <- Modules]
                                  end
                          end
                  end, Paths).

remove_from_code_path(Paths) ->
    lists:foreach(fun(Path) ->
                          Name = filename:basename(Path, "/ebin"),
                          App = list_to_atom(Name),
                          application:load(App),
                          case application:get_key(App, modules) of
                              undefined ->
                                  application:unload(App),
                                  ok;
                              {ok, Modules} ->
                                  application:unload(App),
                                  [case erlang:check_process_code(self(), M) of
                                       false ->
                                           code:purge(M), code:delete(M);
                                       _ ->
                                           ?DEBUG("~p can't purge ~p safely, doing a soft purge", [self(), M]),
                                           code:soft_purge(M) andalso code:delete(M)
                                   end || M <- Modules]
                          end,
                          code:del_path(Path)
                  end, lists:usort(Paths)).

%% @doc Revert to only having the beams necessary for running rebar3 and
%% plugins in the path
-spec cleanup_code_path([string()]) -> true | {error, term()}.
cleanup_code_path(OrigPath) ->
    CurrentPath = code:get_path(),
    AddedPaths = CurrentPath -- OrigPath,
    %% If someone has removed paths, it's hard to get them back into
    %% the right order, but since this is currently rare, we can just
    %% fall back to code:set_path/1.
    case CurrentPath -- AddedPaths of
        OrigPath ->
            _ = [code:del_path(Path) || Path <- AddedPaths],
            true;
        _ ->
            code:set_path(OrigPath)
    end.

new_task([], Acc) -> lists:reverse(Acc);
new_task([TaskList|Rest], Acc) ->
    case re:split(TaskList, ",", [{return, list}, {parts, 2}, unicode]) of
        %% `do` consumes all remaining args
        ["do" = Task] ->
            lists:reverse([{Task, Rest}|Acc]);
        %% single task terminated by a comma
        [Task, ""]    -> new_task(Rest, [{Task, []}|Acc]);
        %% sequence of two or more tasks
        [Task, More]  -> new_task([More|Rest], [{Task, []}|Acc]);
        %% single task not terminated by a comma
        [Task]        -> arg_or_flag(Rest, [{Task, []}|Acc])
    end.

arg_or_flag([], [{Task, Args}|Acc]) ->
    lists:reverse([{Task, lists:reverse(Args)}|Acc]);
%% case where you have `foo , bar`
arg_or_flag([","|Rest], Acc) -> new_task(Rest, Acc);
%% case where you have `foo ,bar`
arg_or_flag(["," ++ Task|Rest], Acc) -> new_task([Task|Rest], Acc);
%% a flag
arg_or_flag(["-" ++ _ = Flag|Rest], [{Task, Args}|Acc]) ->
    case maybe_ends_in_comma(Flag) of
        false   -> arg_or_flag(Rest, [{Task, [Flag|Args]}|Acc]);
        NewFlag -> new_task(Rest, [{Task,
                                    lists:reverse([NewFlag|Args])}|Acc])
    end;
%% an argument or a sequence of arguments
arg_or_flag([ArgList|Rest], [{Task, Args}|Acc]) ->
    case re:split(ArgList, ",", [{return, list}, {parts, 2}, unicode]) of
        %% single arg terminated by a comma
        [Arg, ""]   -> new_task(Rest, [{Task,
                                        lists:reverse([Arg|Args])}|Acc]);
        %% sequence of two or more args/tasks
        [Arg, More] -> new_task([More|Rest], [{Task,
                                              lists:reverse([Arg|Args])}|Acc]);
        %% single arg not terminated by a comma
        [Arg] -> arg_or_flag(Rest, [{Task, [Arg|Args]}|Acc])
    end.

maybe_ends_in_comma(H) ->
    case lists:reverse(H) of
        "," ++ Flag -> lists:reverse(Flag);
        _           -> false
    end.

get_http_vars(Scheme) ->
    OS = case os:getenv(atom_to_list(Scheme)) of
        Str when is_list(Str) -> Str;
        _ -> []
    end,
    GlobalConfigFile = rebar_dir:global_config(),
    Config = rebar_config:consult_file(GlobalConfigFile),
    proplists:get_value(Scheme, Config, OS).

set_httpc_options() ->
    set_httpc_options(https_proxy, get_http_vars(https_proxy)),
    set_httpc_options(proxy, get_http_vars(http_proxy)).

set_httpc_options(_, []) ->
    ok;

set_httpc_options(Scheme, Proxy) ->
    URI = normalise_proxy(Scheme, Proxy),
    {ok, {_, UserInfo, Host, Port, _, _}} = http_uri:parse(URI),
    httpc:set_options([{Scheme, {{Host, Port}, []}}], rebar),
    set_proxy_auth(UserInfo).

normalise_proxy(Scheme, URI) ->
    case re:run(URI, "://", [unicode]) of
        nomatch when Scheme =:= https_proxy -> "https://" ++ URI;
        nomatch when Scheme =:= proxy -> "http://" ++ URI;
        _ -> URI
    end.

url_append_path(Url, ExtraPath) ->
     case http_uri:parse(Url) of
         {ok, {Scheme, UserInfo, Host, Port, Path, Query}} ->
             {ok, lists:append([atom_to_list(Scheme), "://", UserInfo, Host, ":", integer_to_list(Port),
                                filename:join(Path, ExtraPath), "?", Query])};
         _ ->
             error
     end.

%% escape\ as\ a\ shell\?
escape_chars(Str) when is_atom(Str) ->
    escape_chars(atom_to_list(Str));
escape_chars(Str) ->
    re:replace(Str, "([ ()?`!$&;\"\'])", "\\\\&",
               [global, {return, list}, unicode]).

%% "escape inside these"
escape_double_quotes(Str) ->
    re:replace(Str, "([\"\\\\`!$&*;])", "\\\\&",
               [global, {return, list}, unicode]).

%% "escape inside these" but allow *
escape_double_quotes_weak(Str) ->
    re:replace(Str, "([\"\\\\`!$&;])", "\\\\&",
               [global, {return, list}, unicode]).

info_useless(Old, New) ->
    [?INFO("App ~ts is no longer needed and can be deleted.", [Name])
     || Name <- Old,
        not lists:member(Name, New)],
    ok.

list_dir(Dir) ->
    %% `list_dir_all` returns raw files which are unsupported
    %% prior to R16 so just fall back to `list_dir` if running
    %% on an earlier vm
    case erlang:function_exported(file, list_dir_all, 1) of
        true  -> file:list_dir_all(Dir);
        false -> file:list_dir(Dir)
    end.

set_proxy_auth([]) ->
    ok;
set_proxy_auth(UserInfo) ->
    [Username, Password] = re:split(UserInfo, ":",
                                    [{return, list}, {parts,2}, unicode]),
    %% password may contain url encoded characters, need to decode them first
    application:set_env(rebar, proxy_auth, [{proxy_auth, {Username, http_uri:decode(Password)}}]).

get_proxy_auth() ->
    case application:get_env(rebar, proxy_auth) of
        undefined -> [];
        {ok, ProxyAuth} -> ProxyAuth
    end.

-spec rebar_utils:is_list_of_strings(term()) -> boolean().
is_list_of_strings(List) when not is_list(hd(List)) ->
    false;
is_list_of_strings(List) when is_list(hd(List)) ->
    true;
is_list_of_strings(List) when is_list(List) ->
    true.

%%------------------------------------------------------------------------------
%% @doc
%% Return the SSL options adequate for the project based on
%% its configuration, including for validation of certs.
%% @end
%%------------------------------------------------------------------------------
-spec ssl_opts(Url) -> Res when
      Url :: string(),
      Res :: proplists:proplist().
ssl_opts(Url) ->
    case get_ssl_config() of
        ssl_verify_enabled ->
            ssl_opts(ssl_verify_enabled, Url);
        ssl_verify_disabled ->
            [{verify, verify_none}]
    end.

%%------------------------------------------------------------------------------
%% @doc
%% Return the SSL options adequate for the project based on
%% its configuration, including for validation of certs.
%% @end
%%------------------------------------------------------------------------------
-spec ssl_opts(Enabled, Url) -> Res when
      Enabled :: atom(),
      Url :: string(),
      Res :: proplists:proplist().
ssl_opts(ssl_verify_enabled, Url) ->
    case check_ssl_version() of
        true ->
            {ok, {_, _, Hostname, _, _, _}} =
                http_uri:parse(rebar_utils:to_list(Url)),
            VerifyFun = {fun ssl_verify_hostname:verify_fun/3,
                         [{check_hostname, Hostname}]},
            CACerts = certifi:cacerts(),
            [{verify, verify_peer}, {depth, 2}, {cacerts, CACerts},
             {partial_chain, fun partial_chain/1}, {verify_fun, VerifyFun}];
        false ->
            ?WARN("Insecure HTTPS request (peer verification disabled), "
                  "please update to OTP 17.4 or later", []),
            [{verify, verify_none}]
    end.

-spec partial_chain(Certs) -> Res when
      Certs :: list(any()),
      Res :: unknown_ca | {trusted_ca, any()}.
partial_chain(Certs) ->
    Certs1 = [{Cert, public_key:pkix_decode_cert(Cert, otp)} || Cert <- Certs],
    CACerts = certifi:cacerts(),
    CACerts1 = [public_key:pkix_decode_cert(Cert, otp) || Cert <- CACerts],
    case ec_lists:find(fun({_, Cert}) ->
                               check_cert(CACerts1, Cert)
                       end, Certs1) of
        {ok, Trusted} ->
            {trusted_ca, element(1, Trusted)};
        _ ->
            unknown_ca
    end.

-spec extract_public_key_info(Cert) -> Res when
      Cert :: #'OTPCertificate'{tbsCertificate::#'OTPTBSCertificate'{}},
      Res :: any().
extract_public_key_info(Cert) ->
    ((Cert#'OTPCertificate'.tbsCertificate)#'OTPTBSCertificate'.subjectPublicKeyInfo).

-spec check_cert(CACerts, Cert) -> Res when
      CACerts :: list(any()),
      Cert :: any(),
      Res :: boolean().
check_cert(CACerts, Cert) ->
    lists:any(fun(CACert) ->
                      extract_public_key_info(CACert) == extract_public_key_info(Cert)
              end, CACerts).

-spec check_ssl_version() ->
    boolean().
check_ssl_version() ->
    case application:get_key(ssl, vsn) of
        {ok, Vsn} ->
            parse_vsn(Vsn) >= {5, 3, 6};
        _ ->
            false
    end.

-spec get_ssl_config() ->
      ssl_verify_disabled | ssl_verify_enabled.
get_ssl_config() ->
    GlobalConfigFile = rebar_dir:global_config(),
    Config = rebar_config:consult_file(GlobalConfigFile),
    case proplists:get_value(ssl_verify, Config, []) of
        false ->
            ssl_verify_disabled;
        _ ->
            ssl_verify_enabled
    end.

-spec parse_vsn(Vsn) -> Res when
      Vsn :: string(),
      Res :: {integer(), integer(), integer()}.
parse_vsn(Vsn) ->
    version_pad(rebar_string:lexemes(Vsn, ".-")).

-spec version_pad(list(nonempty_string())) -> Res when
      Res :: {integer(), integer(), integer()}.
version_pad([Major]) ->
    {list_to_integer(Major), 0, 0};
version_pad([Major, Minor]) ->
    {list_to_integer(Major), list_to_integer(Minor), 0};
version_pad([Major, Minor, Patch]) ->
    {list_to_integer(Major), list_to_integer(Minor), list_to_integer(Patch)};
version_pad([Major, Minor, Patch | _]) ->
    {list_to_integer(Major), list_to_integer(Minor), list_to_integer(Patch)}.


-ifdef(filelib_find_source).
find_source(Filename, Dir, Rules) ->
    filelib:find_source(Filename, Dir, Rules).
-else.
%% Looks for a file relative to a given directory

-type find_file_rule() :: {ObjDirSuffix::string(), SrcDirSuffix::string()}.

%% Looks for a source file relative to the object file name and directory

-type find_source_rule() :: {ObjExtension::string(), SrcExtension::string(),
                             [find_file_rule()]}.

keep_suffix_search_rules(Rules) ->
    [T || {_,_,_}=T <- Rules].

-spec find_source(file:filename(), file:filename(), [find_source_rule()]) ->
        {ok, file:filename()} | {error, not_found}.
find_source(Filename, Dir, Rules) ->
    try_suffix_rules(keep_suffix_search_rules(Rules), Filename, Dir).

try_suffix_rules(Rules, Filename, Dir) ->
    Ext = filename:extension(Filename),
    try_suffix_rules(Rules, filename:rootname(Filename, Ext), Dir, Ext).

try_suffix_rules([{Ext,Src,Rules}|Rest], Root, Dir, Ext)
  when is_list(Src), is_list(Rules) ->
    case try_dir_rules(add_local_search(Rules), Root ++ Src, Dir) of
        {ok, File} -> {ok, File};
        _Other ->
            try_suffix_rules(Rest, Root, Dir, Ext)
    end;
try_suffix_rules([_|Rest], Root, Dir, Ext) ->
    try_suffix_rules(Rest, Root, Dir, Ext);
try_suffix_rules([], _Root, _Dir, _Ext) ->
    {error, not_found}.

%% ensuring we check the directory of the object file before any other directory
add_local_search(Rules) ->
    Local = {"",""},
    [Local] ++ lists:filter(fun (X) -> X =/= Local end, Rules).

try_dir_rules([{From, To}|Rest], Filename, Dir)
  when is_list(From), is_list(To) ->
    case try_dir_rule(Dir, Filename, From, To) of
	{ok, File} -> {ok, File};
	error      -> try_dir_rules(Rest, Filename, Dir)
    end;
try_dir_rules([], _Filename, _Dir) ->
    {error, not_found}.

try_dir_rule(Dir, Filename, From, To) ->
    case lists:suffix(From, Dir) of
	true ->
	    NewDir = lists:sublist(Dir, 1, length(Dir)-length(From))++To,
	    Src = filename:join(NewDir, Filename),
	    case filelib:is_regular(Src) of
		true -> {ok, Src};
		false -> find_regular_file(filelib:wildcard(Src))
	    end;
	false ->
	    error
    end.

find_regular_file([]) ->
    error;
find_regular_file([File|Files]) ->
    case filelib:is_regular(File) of
        true -> {ok, File};
        false -> find_regular_file(Files)
    end.
-endif.