%% -*- erlang-indent-level: 4; indent-tabs-mode: nil; fill-column: 80 -*-
%%% Copyright 2012 Erlware, LLC. All Rights Reserved.
%%%
%%% This file is provided to you under the Apache License,
%%% Version 2.0 (the "License"); you may not use this file
%%% except in compliance with the License. You may obtain
%%% a copy of the License at
%%%
%%% http://www.apache.org/licenses/LICENSE-2.0
%%%
%%% Unless required by applicable law or agreed to in writing,
%%% software distributed under the License is distributed on an
%%% "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
%%% KIND, either express or implied. See the License for the
%%% specific language governing permissions and limitations
%%% under the License.
%%%---------------------------------------------------------------------------
%%% @author Eric Merritt <[email protected]>
%%% @copyright (C) 2012 Erlware, LLC.
%%%
%%% @doc This provider uses the lib_dir setting of the state. It searches the
%%% Lib Dirs looking for all OTP Applications that are available. When it finds
%%% those OTP Applications it loads the information about them and adds them to
%%% the state of available apps. This implements provider behaviour.
-module(rlx_dscv_util).
-export([do/2,
format_error/1]).
-include("relx.hrl").
%%============================================================================
%% Types
%%============================================================================
-type process_fun(Result) :: fun((file:name(), file | directory) ->
{ok, Result} |
{error, term()} |
{ok, Result, Recurse::boolean()} |
{noresult, Recurse::boolean()} |
{error, term()}).
%%============================================================================
%% API
%%============================================================================
%% @doc recursively dig down into the library directories specified in the state
%% looking for OTP Applications
-spec do(process_fun([term()] | term()), [file:name()]) ->
[term() | {error, term()}].
do(ProcessDir, LibDirs) ->
lists:flatten(ec_plists:map(fun(LibDir) ->
discover_dir(ProcessDir, LibDir,
ec_file:type(LibDir))
end, LibDirs)).
-spec format_error([ErrorDetail::term()]) -> iolist().
format_error(ErrorDetails)
when erlang:is_list(ErrorDetails) ->
[[format_detail(ErrorDetail), "\n"] || ErrorDetail <- ErrorDetails].
%%%===================================================================
%%% Internal Functions
%%%===================================================================
-spec format_detail(ErrorDetail::term()) -> iolist().
format_detail({accessing, File, eaccess}) ->
io_lib:format("permission denied accessing file ~s", [File]);
format_detail({accessing, File, Type}) ->
io_lib:format("error (~p) accessing file ~s", [Type, File]);
format_detail({not_a_directory, EbinDir}) ->
io_lib:format("~s is not a directory when it should be a directory", [EbinDir]).
-spec discover_dir(process_fun([term()] | term()),
file:name(),
directory | file | symlink | undefined) ->
[{ok, term()}
| {error, Reason::term()}]
| []
| {ok, term()}
| {error, Reason::term()}.
discover_dir(_ProcessDir, _File, undefined) ->
[];
discover_dir(ProcessDir, File, directory) ->
case ProcessDir(File, directory) of
{ok, Result, true} ->
[{ok, Result} | recurse(ProcessDir, File)];
{noresult, true} ->
recurse(ProcessDir, File);
{ok, Result, _} ->
[{ok, Result}];
{noresult, _} ->
[];
Err = {error, _} ->
[Err]
end;
discover_dir(ProcessDir, File, file) ->
case ProcessDir(File, file) of
{ok, Result} ->
[{ok, Result}];
{noresult, _} ->
[];
Warn = {warning, _} ->
[Warn];
Err = {error, _} ->
[Err]
end;
discover_dir(ProcessDir, File, symlink) ->
case filelib:is_dir(File) of
false ->
discover_dir(ProcessDir, File, file);
true ->
discover_real_symlink_dir(ProcessDir, File)
end.
discover_real_symlink_dir(ProcessDir, File) ->
{ok, ActualRealDir} = file:read_link(File),
case lists:prefix(iolist_to_list(filename:absname(ActualRealDir)),
iolist_to_list(filename:absname(File))) of
true ->
%% Ignore cycles
[];
false ->
case ProcessDir(File, directory) of
{ok, Result, true} ->
[{ok, Result} | recurse(ProcessDir, File)];
{noresult, true} ->
recurse(ProcessDir, File);
{ok, Result, _} ->
[{ok, Result}];
{noresult, _} ->
[];
Err = {error, _} ->
[Err]
end
end.
recurse(ProcessDir, File) ->
case file:list_dir(File) of
{error, Reason} ->
{error, {accessing, File, Reason}};
{ok, List} ->
ec_plists:map(fun(LibDir) ->
discover_dir(ProcessDir, LibDir, ec_file:type(LibDir))
end, [filename:join([File, Dir]) || Dir <- List])
end.
iolist_to_list(IoList) ->
erlang:binary_to_list(erlang:iolist_to_binary(IoList)).
