%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2012. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%
%% A primary loader, provides two different methods to fetch a file:
%% efile and inet. The efile method is simple communication with a
%% port program.
%%
%% The distribution loading was removed and replaced with
%% inet loading
%%
%% The start_it/4 function initializes a record with callback
%% functions used to handle the interface functions.
%%
-module(erl_prim_loader).
%% If the macro DEBUG is defined during compilation,
%% debug printouts are done through erlang:display/1.
%% Activate this feature by starting the compiler
%% with> erlc -DDEBUG ...
%% or by> setenv ERL_COMPILER_FLAGS DEBUG
%% before running make (in the OTP make system)
%% (the example is for tcsh)
-include("inet_boot.hrl").
%% Public
-export([start/3, set_path/1, get_path/0, get_file/1, get_files/2,
list_dir/1, read_file_info/1, get_cwd/0, get_cwd/1]).
%% Used by erl_boot_server
-export([prim_init/0, prim_get_file/2, prim_list_dir/2,
prim_read_file_info/2, prim_get_cwd/2]).
%% Used by escript and code
-export([set_primary_archive/3, release_archives/0]).
-include_lib("kernel/include/file.hrl").
-type host() :: atom().
-record(prim_state, {debug :: boolean(),
cache,
primary_archive}).
-type prim_state() :: #prim_state{}.
-record(state,
{loader :: 'efile' | 'inet',
hosts = [] :: [host()], % hosts list (to boot from)
id, % not used any more?
data :: 'noport' | port(), % data port etc
timeout :: timeout(), % idle timeout
%% Number of timeouts before archives are released
n_timeouts :: non_neg_integer(),
multi_get = false :: boolean(),
prim_state :: prim_state()}). % state for efile code loader
-define(IDLE_TIMEOUT, 60000). %% tear inet connection after 1 minutes
-define(N_TIMEOUTS, 6). %% release efile archive after 6 minutes
%% Defines for inet as prim_loader
-define(INET_FAMILY, inet).
-define(INET_ADDRESS, {0,0,0,0}).
-ifdef(DEBUG).
-define(dbg(Tag, Data), erlang:display({Tag,Data})).
-else.
-define(dbg(Tag, Data), true).
-endif.
-define(SAFE2(Expr, State),
fun() ->
case catch Expr of
{'EXIT',XXXReason} -> {{error,XXXReason}, State};
XXXRes -> XXXRes
end
end()).
debug(#prim_state{debug = Deb}, Term) ->
case Deb of
false -> ok;
true -> erlang:display(Term)
end.
%%% --------------------------------------------------------
%%% Interface Functions.
%%% --------------------------------------------------------
-spec start(Id, Loader, Hosts) ->
{'ok', Pid} | {'error', What} when
Id :: term(),
Loader :: atom() | string(),
Hosts :: Host | [Host],
Host :: host(),
Pid :: pid(),
What :: term().
start(Id, Pgm, Hosts) when is_atom(Hosts) ->
start(Id, Pgm, [Hosts]);
start(Id, Pgm0, Hosts) ->
Pgm = if
is_atom(Pgm0) ->
atom_to_list(Pgm0);
true ->
Pgm0
end,
Self = self(),
Pid = spawn_link(fun() -> start_it(Pgm, Id, Self, Hosts) end),
register(erl_prim_loader, Pid),
receive
{Pid,ok} ->
{ok,Pid};
{'EXIT',Pid,Reason} ->
{error,Reason}
end.
%% Hosts must be a list of form ['1.2.3.4' ...]
start_it("inet", Id, Pid, Hosts) ->
process_flag(trap_exit, true),
?dbg(inet, {Id,Pid,Hosts}),
AL = ipv4_list(Hosts),
?dbg(addresses, AL),
{ok,Tcp} = find_master(AL),
init_ack(Pid),
PS = prim_init(),
State = #state {loader = inet,
hosts = AL,
id = Id,
data = Tcp,
timeout = ?IDLE_TIMEOUT,
n_timeouts = ?N_TIMEOUTS,
prim_state = PS},
loop(State, Pid, []);
start_it("efile", Id, Pid, _Hosts) ->
process_flag(trap_exit, true),
{ok, Port} = prim_file:open([binary]),
init_ack(Pid),
MultiGet = case erlang:system_info(thread_pool_size) of
0 -> false;
_ -> true
end,
PS = prim_init(),
State = #state {loader = efile,
id = Id,
data = Port,
timeout = infinity,
multi_get = MultiGet,
prim_state = PS},
loop(State, Pid, []).
init_ack(Pid) ->
Pid ! {self(),ok},
ok.
-spec set_path(Path) -> 'ok' when
Path :: [Dir :: string()].
set_path(Paths) when is_list(Paths) ->
request({set_path,Paths}).
-spec get_path() -> {'ok', Path} when
Path :: [Dir :: string()].
get_path() ->
request({get_path,[]}).
-spec get_file(Filename) -> {'ok', Bin, FullName} | 'error' when
Filename :: atom() | string(),
Bin :: binary(),
FullName :: string().
get_file(File) when is_atom(File) ->
get_file(atom_to_list(File));
get_file(File) ->
check_file_result(get_file, File, request({get_file,File})).
-spec get_files([{atom(), string()}],
fun((atom(),binary(),string()) -> 'ok' | {'error', atom()})) ->
'ok' | {'error', atom()}.
get_files(ModFiles, Fun) ->
case request({get_files,{ModFiles,Fun}}) of
E = {error,_M} ->
E;
{error,Reason,M} ->
check_file_result(get_files, M, {error,Reason}),
{error,M};
ok ->
ok
end.
-spec list_dir(Dir) -> {'ok', Filenames} | 'error' when
Dir :: string(),
Filenames :: [Filename :: string()].
list_dir(Dir) ->
check_file_result(list_dir, Dir, request({list_dir,Dir})).
-spec read_file_info(Filename) -> {'ok', FileInfo} | 'error' when
Filename :: string(),
FileInfo :: file:file_info().
read_file_info(File) ->
check_file_result(read_file_info, File, request({read_file_info,File})).
-spec get_cwd() -> {'ok', string()} | 'error'.
get_cwd() ->
check_file_result(get_cwd, [], request({get_cwd,[]})).
-spec get_cwd(string()) -> {'ok', string()} | 'error'.
get_cwd(Drive) ->
check_file_result(get_cwd, Drive, request({get_cwd,[Drive]})).
-spec set_primary_archive(File :: string() | 'undefined',
ArchiveBin :: binary() | 'undefined',
FileInfo :: #file_info{} | 'undefined')
-> {ok, [string()]} | {error,_}.
set_primary_archive(undefined, undefined, undefined) ->
request({set_primary_archive, undefined, undefined, undefined});
set_primary_archive(File, ArchiveBin, FileInfo)
when is_list(File), is_binary(ArchiveBin), is_record(FileInfo, file_info) ->
request({set_primary_archive, File, ArchiveBin, FileInfo}).
-spec release_archives() -> 'ok' | {'error', _}.
release_archives() ->
request(release_archives).
request(Req) ->
Loader = whereis(erl_prim_loader),
Loader ! {self(),Req},
receive
{Loader,Res} ->
Res;
{'EXIT',Loader,_What} ->
error
end.
check_file_result(_, _, {error,enoent}) ->
error;
check_file_result(_, _, {error,enotdir}) ->
error;
check_file_result(Func, Target, {error,Reason}) ->
case (catch atom_to_list(Reason)) of
{'EXIT',_} -> % exit trapped
error;
Errno -> % errno
Process = case process_info(self(), registered_name) of
{registered_name,R} ->
"Process: " ++ atom_to_list(R) ++ ".";
_ ->
""
end,
TargetStr =
if is_atom(Target) -> atom_to_list(Target);
is_list(Target) -> Target;
true -> []
end,
Report =
case TargetStr of
[] ->
"File operation error: " ++ Errno ++ ". " ++
"Function: " ++ atom_to_list(Func) ++ ". " ++ Process;
_ ->
"File operation error: " ++ Errno ++ ". " ++
"Target: " ++ TargetStr ++ ". " ++
"Function: " ++ atom_to_list(Func) ++ ". " ++ Process
end,
%% this is equal to calling error_logger:error_report/1 which
%% we don't want to do from code_server during system boot
error_logger ! {notify,{error_report,group_leader(),
{self(),std_error,Report}}},
error
end;
check_file_result(_, _, Other) ->
Other.
%%% --------------------------------------------------------
%%% The main loop.
%%% --------------------------------------------------------
loop(State, Parent, Paths) ->
receive
{Pid,Req} when is_pid(Pid) ->
%% erlang:display(Req),
{Resp,State2,Paths2} =
case Req of
{set_path,NewPaths} ->
{ok,State,to_strs(NewPaths)};
{get_path,_} ->
{{ok,Paths},State,Paths};
{get_file,File} ->
{Res,State1} = handle_get_file(State, Paths, File),
{Res,State1,Paths};
{get_files,{ModFiles,Fun}} ->
{Res,State1} = handle_get_files(State, ModFiles, Paths, Fun),
{Res,State1,Paths};
{list_dir,Dir} ->
{Res,State1} = handle_list_dir(State, Dir),
{Res,State1,Paths};
{read_file_info,File} ->
{Res,State1} = handle_read_file_info(State, File),
{Res,State1,Paths};
{get_cwd,[]} ->
{Res,State1} = handle_get_cwd(State, []),
{Res,State1,Paths};
{get_cwd,[_]=Args} ->
{Res,State1} = handle_get_cwd(State, Args),
{Res,State1,Paths};
{set_primary_archive,File,Bin,FileInfo} ->
{Res,State1} = handle_set_primary_archive(State, File, Bin, FileInfo),
{Res,State1,Paths};
release_archives ->
{Res,State1} = handle_release_archives(State),
{Res,State1,Paths};
_Other ->
{ignore,State,Paths}
end,
if Resp =:= ignore -> ok;
true -> Pid ! {self(),Resp}, ok
end,
if
is_record(State2, state) ->
loop(State2, Parent, Paths2);
true ->
exit({bad_state, Req, State2})
end;
{'EXIT',Parent,W} ->
_State1 = handle_stop(State),
exit(W);
{'EXIT',P,W} ->
State1 = handle_exit(State, P, W),
loop(State1, Parent, Paths);
_Message ->
loop(State, Parent, Paths)
after State#state.timeout ->
State1 = handle_timeout(State, Parent),
loop(State1, Parent, Paths)
end.
handle_get_files(State = #state{multi_get = true}, ModFiles, Paths, Fun) ->
?SAFE2(efile_multi_get_file_from_port(State, ModFiles, Paths, Fun), State);
handle_get_files(State, _ModFiles, _Paths, _Fun) -> % no multi get
{{error,no_multi_get},State}.
handle_get_file(State = #state{loader = efile}, Paths, File) ->
?SAFE2(efile_get_file_from_port(State, File, Paths), State);
handle_get_file(State = #state{loader = inet}, Paths, File) ->
?SAFE2(inet_get_file_from_port(State, File, Paths), State).
handle_set_primary_archive(State= #state{loader = efile}, File, Bin, FileInfo) ->
?SAFE2(efile_set_primary_archive(State, File, Bin, FileInfo), State).
handle_release_archives(State= #state{loader = efile}) ->
?SAFE2(efile_release_archives(State), State).
handle_list_dir(State = #state{loader = efile}, Dir) ->
?SAFE2(efile_list_dir(State, Dir), State);
handle_list_dir(State = #state{loader = inet}, Dir) ->
?SAFE2(inet_list_dir(State, Dir), State).
handle_read_file_info(State = #state{loader = efile}, File) ->
?SAFE2(efile_read_file_info(State, File), State);
handle_read_file_info(State = #state{loader = inet}, File) ->
?SAFE2(inet_read_file_info(State, File), State).
handle_get_cwd(State = #state{loader = efile}, Drive) ->
?SAFE2(efile_get_cwd(State, Drive), State);
handle_get_cwd(State = #state{loader = inet}, Drive) ->
?SAFE2(inet_get_cwd(State, Drive), State).
handle_stop(State = #state{loader = efile}) ->
efile_stop_port(State);
handle_stop(State = #state{loader = inet}) ->
inet_stop_port(State).
handle_exit(State = #state{loader = efile}, Who, Reason) ->
efile_exit_port(State, Who, Reason);
handle_exit(State = #state{loader = inet}, Who, Reason) ->
inet_exit_port(State, Who, Reason).
handle_timeout(State = #state{loader = efile}, Parent) ->
efile_timeout_handler(State, Parent);
handle_timeout(State = #state{loader = inet}, Parent) ->
inet_timeout_handler(State, Parent).
%%% --------------------------------------------------------
%%% Functions which handle efile as prim_loader (default).
%%% --------------------------------------------------------
%%% Reading many files in parallel is an optimization.
%%% See also comment in init.erl.
%% -> {ok,State} | {{error,Module},State} | {{error,Reason,Module},State}
efile_multi_get_file_from_port(State, ModFiles, Paths, Fun) ->
Ref = make_ref(),
%% More than 200 processes is no gain.
Max = erlang:min(200, erlang:system_info(thread_pool_size)),
efile_multi_get_file_from_port2(ModFiles, 0, Max, State, Paths, Fun, Ref, ok).
efile_multi_get_file_from_port2([MF | MFs], Out, Max, State, Paths, Fun, Ref, Ret) when Out < Max ->
Self = self(),
_Pid = spawn(fun() -> efile_par_get_file(Ref, State, MF, Paths, Self, Fun) end),
efile_multi_get_file_from_port2(MFs, Out+1, Max, State, Paths, Fun, Ref, Ret);
efile_multi_get_file_from_port2(MFs, Out, Max, _State, Paths, Fun, Ref, Ret) when Out > 0 ->
receive
{Ref, ok, State1} ->
efile_multi_get_file_from_port2(MFs, Out-1, Max, State1, Paths, Fun, Ref, Ret);
{Ref, {error,_Mod} = Error, State1} ->
efile_multi_get_file_from_port2(MFs, Out-1, Max, State1, Paths, Fun, Ref, Error);
{Ref, MF, {error,emfile,State1}} ->
%% Max can take negative values. Out cannot.
efile_multi_get_file_from_port2([MF | MFs], Out-1, Max-1, State1, Paths, Fun, Ref, Ret);
{Ref, {M,_F}, {error,Error,State1}} ->
efile_multi_get_file_from_port2(MFs, Out-1, 0, State1, Paths, Fun, Ref, {error,Error,M})
end;
efile_multi_get_file_from_port2(_MFs, 0, _Max, State, _Paths, _Fun, _Ref, Ret) ->
{Ret,State}.
efile_par_get_file(Ref, State, {Mod,File} = MF, Paths, Pid, Fun) ->
%% One port for each file read in "parallel":
case prim_file:open([binary]) of
{ok, Port} ->
Port0 = State#state.data,
State1 = State#state{data = Port},
R = case efile_get_file_from_port(State1, File, Paths) of
{{error,Reason},State2} ->
{Ref,MF,{error,Reason,State2}};
{{ok,BinFile,Full},State2} ->
%% Fun(...) -> ok | {error,Mod}
{Ref,Fun(Mod, BinFile, Full),State2#state{data=Port0}}
end,
prim_file:close(Port),
Pid ! R;
{error, Error} ->
Pid ! {Ref,MF,{error,Error,State}}
end.
%% -> {{ok,BinFile,File},State} | {{error,Reason},State}
efile_get_file_from_port(State, File, Paths) ->
case is_basename(File) of
false -> % get absolute file name.
efile_get_file_from_port2(State, File);
true when Paths =:= [] -> % get plain file name.
efile_get_file_from_port2(State, File);
true -> % use paths.
efile_get_file_from_port3(State, File, Paths)
end.
efile_get_file_from_port2(#state{prim_state = PS} = State, File) ->
{Res, PS2} = prim_get_file(PS, File),
case Res of
{error,port_died} ->
exit('prim_load port died');
{error,Reason} ->
{{error,Reason},State#state{prim_state = PS2}};
{ok,BinFile} ->
{{ok,BinFile,File},State#state{prim_state = PS2}}
end.
efile_get_file_from_port3(State, File, [P | Paths]) ->
case efile_get_file_from_port2(State, join(P, File)) of
{{error,Reason},State1} when Reason =/= emfile ->
case Paths of
[] -> % return last error
{{error,Reason},State1};
_ -> % try more paths
efile_get_file_from_port3(State1, File, Paths)
end;
Result ->
Result
end;
efile_get_file_from_port3(State, _File, []) ->
{{error,enoent},State}.
efile_set_primary_archive(#state{prim_state = PS} = State, File, Bin, FileInfo) ->
{Res, PS2} = prim_set_primary_archive(PS, File, Bin, FileInfo),
{Res,State#state{prim_state = PS2}}.
efile_release_archives(#state{prim_state = PS} = State) ->
{Res, PS2} = prim_release_archives(PS),
{Res,State#state{prim_state = PS2}}.
efile_list_dir(#state{prim_state = PS} = State, Dir) ->
{Res, PS2} = prim_list_dir(PS, Dir),
{Res, State#state{prim_state = PS2}}.
efile_read_file_info(#state{prim_state = PS} = State, File) ->
{Res, PS2} = prim_read_file_info(PS, File),
{Res, State#state{prim_state = PS2}}.
efile_get_cwd(#state{prim_state = PS} = State, Drive) ->
{Res, PS2} = prim_get_cwd(PS, Drive),
{Res, State#state{prim_state = PS2}}.
efile_stop_port(#state{data=Port}=State) ->
prim_file:close(Port),
State#state{data=noport}.
efile_exit_port(State, Port, Reason) when State#state.data =:= Port ->
exit({port_died,Reason});
efile_exit_port(State, _Port, _Reason) ->
State.
efile_timeout_handler(#state{n_timeouts = N} = State, _Parent) ->
if
N =< 0 ->
{_Res, State2} = efile_release_archives(State),
State2#state{n_timeouts = ?N_TIMEOUTS};
true ->
State#state{n_timeouts = N - 1}
end.
%%% --------------------------------------------------------
%%% Functions which handle inet prim_loader
%%% --------------------------------------------------------
%%
%% Connect to a boot master
%% return {ok, Socket} TCP
%% AL is a list of boot servers (including broadcast addresses)
%%
find_master(AL) ->
find_master(AL, ?EBOOT_RETRY, ?EBOOT_REQUEST_DELAY, ?EBOOT_SHORT_RETRY_SLEEP,
?EBOOT_UNSUCCESSFUL_TRIES, ?EBOOT_LONG_RETRY_SLEEP).
find_master(AL, Retry, ReqDelay, SReSleep, Tries, LReSleep) ->
{ok,U} = ll_udp_open(0),
find_master(U, Retry, AL, ReqDelay, SReSleep, [], Tries, LReSleep).
%%
%% Master connect loop
%%
find_master(U, Retry, AddrL, ReqDelay, SReSleep, Ignore, Tries, LReSleep) ->
case find_loop(U, Retry, AddrL, ReqDelay, SReSleep, Ignore,
Tries, LReSleep) of
[] ->
find_master(U, Retry, AddrL, ReqDelay, SReSleep, Ignore,
Tries, LReSleep);
Servers ->
?dbg(servers, Servers),
case connect_master(Servers) of
{ok, Socket} ->
ll_close(U),
{ok, Socket};
_Error ->
find_master(U, Retry, AddrL, ReqDelay, SReSleep,
Servers ++ Ignore, Tries, LReSleep)
end
end.
connect_master([{_Prio,IP,Port} | Servers]) ->
case ll_tcp_connect(0, IP, Port) of
{ok, S} -> {ok, S};
_Error -> connect_master(Servers)
end;
connect_master([]) ->
{error, ebusy}.
%%
%% Always return a list of boot servers or hang.
%%
find_loop(U, Retry, AL, ReqDelay, SReSleep, Ignore, Tries, LReSleep) ->
case find_loop(U, Retry, AL, ReqDelay, []) of
[] -> % no response from any server
erlang:display({erl_prim_loader,'no server found'}), % lifesign
Tries1 =
if Tries > 0 ->
sleep(SReSleep),
Tries - 1;
true ->
sleep(LReSleep),
0
end,
find_loop(U, Retry, AL, ReqDelay, SReSleep, Ignore, Tries1, LReSleep);
Servers ->
keysort(1, Servers -- Ignore)
end.
%% broadcast or send
find_loop(_U, 0, _AL, _Delay, Acc) ->
Acc;
find_loop(U, Retry, AL, Delay, Acc) ->
send_all(U, AL, [?EBOOT_REQUEST, erlang:system_info(version)]),
find_collect(U, Retry-1, AL, Delay, Acc).
find_collect(U,Retry,AL,Delay,Acc) ->
receive
{udp, U, IP, _Port, [$E,$B,$O,$O,$T,$R,Priority,T1,T0 | _Version]} ->
Elem = {Priority,IP,T1*256+T0},
?dbg(got, Elem),
case member(Elem, Acc) of
false -> find_collect(U, Retry, AL, Delay, [Elem | Acc]);
true -> find_collect(U, Retry, AL, Delay, Acc)
end;
_Garbage ->
?dbg(collect_garbage, _Garbage),
find_collect(U, Retry, AL, Delay, Acc)
after Delay ->
?dbg(collected, Acc),
case keymember(0, 1, Acc) of %% got high priority server?
true -> Acc;
false -> find_loop(U, Retry, AL, Delay, Acc)
end
end.
sleep(Time) ->
receive after Time -> ok end.
inet_exit_port(State, Port, _Reason) when State#state.data =:= Port ->
State#state{data = noport, timeout = infinity};
inet_exit_port(State, _, _) ->
State.
inet_timeout_handler(State, _Parent) ->
Tcp = State#state.data,
if is_port(Tcp) -> ll_close(Tcp);
true -> ok
end,
State#state{timeout = infinity, data = noport}.
%% -> {{ok,BinFile,Tag},State} | {{error,Reason},State}
inet_get_file_from_port(State, File, Paths) ->
case is_basename(File) of
false -> % get absolute file name.
inet_send_and_rcv({get,File}, File, State);
true when Paths =:= [] -> % get plain file name.
inet_send_and_rcv({get,File}, File, State);
true -> % use paths.
inet_get_file_from_port1(File, Paths, State)
end.
inet_get_file_from_port1(File, [P | Paths], State) ->
File1 = join(P, File),
case inet_send_and_rcv({get,File1}, File1, State) of
{{error,Reason},State1} ->
case Paths of
[] -> % return last error
{{error,Reason},State1};
_ -> % try more paths
inet_get_file_from_port1(File, Paths, State1)
end;
Result -> Result
end;
inet_get_file_from_port1(_File, [], State) ->
{{error,file_not_found},State}.
inet_send_and_rcv(Msg, Tag, State) when State#state.data =:= noport ->
{ok,Tcp} = find_master(State#state.hosts), %% reconnect
inet_send_and_rcv(Msg, Tag, State#state{data = Tcp,
timeout = ?IDLE_TIMEOUT});
inet_send_and_rcv(Msg, Tag, #state{data = Tcp, timeout = Timeout} = State) ->
prim_inet:send(Tcp, term_to_binary(Msg)),
receive
{tcp,Tcp,BinMsg} ->
case catch binary_to_term(BinMsg) of
{get,{ok,BinFile}} ->
{{ok,BinFile,Tag},State};
{_Cmd,Res={ok,_}} ->
{Res,State};
{_Cmd,{error,Error}} ->
{{error,Error},State};
{error,Error} ->
{{error,Error},State};
{'EXIT',Error} ->
{{error,Error},State}
end;
{tcp_closed,Tcp} ->
%% Ok we must reconnect
inet_send_and_rcv(Msg, Tag, State#state{data = noport});
{tcp_error,Tcp,_Reason} ->
%% Ok we must reconnect
inet_send_and_rcv(Msg, Tag, inet_stop_port(State));
{'EXIT', Tcp, _} ->
%% Ok we must reconnect
inet_send_and_rcv(Msg, Tag, State#state{data = noport})
after Timeout ->
%% Ok we must reconnect
inet_send_and_rcv(Msg, Tag, inet_stop_port(State))
end.
%% -> {{ok,List},State} | {{error,Reason},State}
inet_list_dir(State, Dir) ->
inet_send_and_rcv({list_dir,Dir}, list_dir, State).
%% -> {{ok,Info},State} | {{error,Reason},State}
inet_read_file_info(State, File) ->
inet_send_and_rcv({read_file_info,File}, read_file_info, State).
%% -> {{ok,Cwd},State} | {{error,Reason},State}
inet_get_cwd(State, []) ->
inet_send_and_rcv(get_cwd, get_cwd, State);
inet_get_cwd(State, [Drive]) ->
inet_send_and_rcv({get_cwd,Drive}, get_cwd, State).
inet_stop_port(#state{data=Tcp}=State) ->
prim_inet:close(Tcp),
State#state{data=noport}.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%% Direct inet_drv access
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
tcp_options() ->
[{mode,binary}, {packet,4}, {active, true}, {deliver,term}].
tcp_timeout() ->
15000.
%% options for udp [list, {broadcast, true}, {active,true}]
udp_options() ->
[{mode,list}, {active, true}, {deliver,term}, {broadcast,true}].
%%
%% INET version IPv4 addresses
%%
ll_tcp_connect(LocalPort, IP, RemotePort) ->
case ll_open_set_bind(tcp, ?INET_FAMILY, stream, tcp_options(),
?INET_ADDRESS, LocalPort) of
{ok,S} ->
case prim_inet:connect(S, IP, RemotePort, tcp_timeout()) of
ok -> {ok, S};
Error -> port_error(S, Error)
end;
Error -> Error
end.
%%
%% Open and initialize an udp port for broadcast
%%
ll_udp_open(P) ->
ll_open_set_bind(udp, ?INET_FAMILY, dgram, udp_options(), ?INET_ADDRESS, P).
ll_open_set_bind(Protocol, Family, Type, SOpts, IP, Port) ->
case prim_inet:open(Protocol, Family, Type) of
{ok, S} ->
case prim_inet:setopts(S, SOpts) of
ok ->
case prim_inet:bind(S, IP, Port) of
{ok,_} ->
{ok, S};
Error -> port_error(S, Error)
end;
Error -> port_error(S, Error)
end;
Error -> Error
end.
ll_close(S) ->
unlink(S),
exit(S, kill).
port_error(S, Error) ->
unlink(S),
prim_inet:close(S),
Error.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-spec prim_init() -> prim_state().
prim_init() ->
Deb =
case init:get_argument(loader_debug) of
{ok, _} -> true;
error -> false
end,
cache_new(#prim_state{debug = Deb}).
prim_release_archives(PS) ->
debug(PS, release_archives),
{Res, PS2} = prim_do_release_archives(PS, get(), []),
debug(PS2, {return, Res}),
{Res, PS2}.
prim_do_release_archives(PS, [{ArchiveFile, DictVal} | KeyVals], Acc) ->
Res =
case DictVal of
{primary, _PrimZip, _FI} ->
ok; % Keep primary archive
{Cache, _FI} ->
debug(PS, {release, cache, ArchiveFile}),
erase(ArchiveFile),
clear_cache(ArchiveFile, Cache)
end,
case Res of
ok ->
prim_do_release_archives(PS, KeyVals, Acc);
{error, Reason} ->
prim_do_release_archives(PS, KeyVals, [{ArchiveFile, Reason} | Acc])
end;
prim_do_release_archives(PS, [], []) ->
{ok, PS#prim_state{primary_archive = undefined}};
prim_do_release_archives(PS, [], Errors) ->
{{error, Errors}, PS#prim_state{primary_archive = undefined}}.
prim_set_primary_archive(PS, undefined, undefined, undefined) ->
debug(PS, {set_primary_archive, clean}),
case PS#prim_state.primary_archive of
undefined ->
Res = {error, enoent},
debug(PS, {return, Res}),
{Res, PS};
ArchiveFile ->
{primary, PrimZip, _FI} = erase(ArchiveFile),
ok = prim_zip:close(PrimZip),
PS2 = PS#prim_state{primary_archive = undefined},
Res = {ok, []},
debug(PS2, {return, Res}),
{Res, PS2}
end;
prim_set_primary_archive(PS, ArchiveFile0, ArchiveBin, #file_info{} = FileInfo)
when is_list(ArchiveFile0), is_binary(ArchiveBin) ->
%% Try the archive file
debug(PS, {set_primary_archive, ArchiveFile0, byte_size(ArchiveBin)}),
ArchiveFile = absname(ArchiveFile0),
{Res3, PS3} =
case PS#prim_state.primary_archive of
undefined ->
Fun =
fun({Funny, _GI, _GB}, A) ->
case Funny of
["", "nibe", RevApp] -> % Reverse ebin
%% Collect ebin directories in archive
Ebin = reverse(RevApp) ++ "/ebin",
{true, [Ebin | A]};
_ ->
{true, A}
end
end,
Ebins0 = [ArchiveFile],
case open_archive({ArchiveFile, ArchiveBin}, FileInfo, Ebins0, Fun) of
{ok, PrimZip, {RevEbins, FI, _}} ->
Ebins = reverse(RevEbins),
debug(PS, {set_primary_archive, Ebins}),
put(ArchiveFile, {primary, PrimZip, FI}),
{{ok, Ebins}, PS#prim_state{primary_archive = ArchiveFile}};
Error ->
debug(PS, {set_primary_archive, Error}),
{Error, PS}
end;
OldArchiveFile ->
debug(PS, {set_primary_archive, clean}),
{primary, PrimZip, _FI} = erase(OldArchiveFile),
ok = prim_zip:close(PrimZip),
PS2 = PS#prim_state{primary_archive = undefined},
prim_set_primary_archive(PS2, ArchiveFile, ArchiveBin, FileInfo)
end,
debug(PS3, {return, Res3}),
{Res3, PS3}.
-spec prim_get_file(prim_state(), file:filename()) -> {_, prim_state()}.
prim_get_file(PS, File) ->
debug(PS, {get_file, File}),
{Res2, PS2} =
case name_split(PS#prim_state.primary_archive, File) of
{file, PrimFile} ->
Res = prim_file:read_file(PrimFile),
{Res, PS};
{archive, ArchiveFile, FileInArchive} ->
debug(PS, {archive_get_file, ArchiveFile, FileInArchive}),
FunnyFile = funny_split(FileInArchive, $/),
Fun =
fun({Funny, _GetInfo, GetBin}, Acc) ->
if
Funny =:= FunnyFile ->
{false, {ok, GetBin()}};
true ->
{true, Acc}
end
end,
apply_archive(PS, Fun, {error, enoent}, ArchiveFile)
end,
debug(PS, {return, Res2}),
{Res2, PS2}.
-spec prim_list_dir(prim_state(), file:filename()) ->
{{'ok', [file:filename()]}, prim_state()}
| {{'error', term()}, prim_state()}.
prim_list_dir(PS, Dir) ->
debug(PS, {list_dir, Dir}),
{Res2, PS3} =
case name_split(PS#prim_state.primary_archive, Dir) of
{file, PrimDir} ->
Res = prim_file:list_dir(PrimDir),
{Res, PS};
{archive, ArchiveFile, FileInArchive} ->
debug(PS, {archive_list_dir, ArchiveFile, FileInArchive}),
FunnyDir = funny_split(FileInArchive, $/),
Fun =
fun({Funny, _GetInfo, _GetBin}, {Status, Names} = Acc) ->
case Funny of
[RevName | FD] when FD =:= FunnyDir ->
case RevName of
"" ->
%% The listed directory
{true, {ok, Names}};
_ ->
%% Plain file
Name = reverse(RevName),
{true, {Status, [Name | Names]}}
end;
["", RevName | FD] when FD =:= FunnyDir ->
%% Directory
Name = reverse(RevName),
{true, {Status, [Name | Names]}};
[RevName] when FunnyDir =:= [""] ->
%% Top file
Name = reverse(RevName),
{true, {ok, [Name | Names]}};
["", RevName] when FunnyDir =:= [""] ->
%% Top file
Name = reverse(RevName),
{true, {ok, [Name | Names]}};
_ ->
%% No match
{true, Acc}
end
end,
{{Status, Names}, PS2} =
apply_archive(PS, Fun, {error, []}, ArchiveFile),
case Status of
ok -> {{ok, Names}, PS2};
error -> {{error, enotdir}, PS2}
end
end,
debug(PS, {return, Res2}),
{Res2, PS3}.
-spec prim_read_file_info(prim_state(), file:filename()) ->
{{'ok', #file_info{}}, prim_state()}
| {{'error', term()}, prim_state()}.
prim_read_file_info(PS, File) ->
debug(PS, {read_file_info, File}),
{Res2, PS2} =
case name_split(PS#prim_state.primary_archive, File) of
{file, PrimFile} ->
Res = prim_file:read_file_info(PrimFile),
{Res, PS};
{archive, ArchiveFile, []} ->
%% Fake top directory
debug(PS, {archive_read_file_info, ArchiveFile}),
case prim_file:read_file_info(ArchiveFile) of
{ok, FI} ->
{{ok, FI#file_info{type = directory}}, PS};
Other ->
{Other, PS}
end;
{archive, ArchiveFile, FileInArchive} ->
debug(PS, {archive_read_file_info, File}),
FunnyFile = funny_split(FileInArchive, $/),
Fun =
fun({Funny, GetInfo, _GetBin}, Acc) ->
case Funny of
[H | T] when H =:= "",
T =:= FunnyFile ->
%% Directory
{false, {ok, GetInfo()}};
F when F =:= FunnyFile ->
%% Plain file
{false, {ok, GetInfo()}};
_ ->
%% No match
{true, Acc}
end
end,
apply_archive(PS, Fun, {error, enoent}, ArchiveFile)
end,
debug(PS2, {return, Res2}),
{Res2, PS2}.
-spec prim_get_cwd(prim_state(), [file:filename()]) ->
{{'error', term()} | {'ok', _}, prim_state()}.
prim_get_cwd(PS, []) ->
debug(PS, {get_cwd, []}),
Res = prim_file:get_cwd(),
debug(PS, {return, Res}),
{Res, PS};
prim_get_cwd(PS, [Drive]) ->
debug(PS, {get_cwd, Drive}),
Res = prim_file:get_cwd(Drive),
debug(PS, {return, Res}),
{Res, PS}.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
apply_archive(PS, Fun, Acc, Archive) ->
case get(Archive) of
undefined ->
case open_archive(Archive, Acc, Fun) of
{ok, PrimZip, {Acc2, FI, _}} ->
debug(PS, {cache, ok}),
put(Archive, {{ok, PrimZip}, FI}),
{Acc2, PS};
Error ->
debug(PS, {cache, Error}),
%% put(Archive, {Error, FI}),
{Error, PS}
end;
{primary, PrimZip, FI} ->
case prim_file:read_file_info(Archive) of
{ok, FI2}
when FI#file_info.mtime =:= FI2#file_info.mtime ->
case foldl_archive(PrimZip, Acc, Fun) of
{ok, _PrimZip2, Acc2} ->
{Acc2, PS};
Error ->
debug(PS, {primary, Error}),
{Error, PS}
end;
Error ->
debug(PS, {cache, {clear, Error}}),
clear_cache(Archive, {ok, PrimZip}),
apply_archive(PS, Fun, Acc, Archive)
end;
{Cache, FI} ->
case prim_file:read_file_info(Archive) of
{ok, FI2}
when FI#file_info.mtime =:= FI2#file_info.mtime ->
case Cache of
{ok, PrimZip} ->
case foldl_archive(PrimZip, Acc, Fun) of
{ok, _PrimZip2, Acc2} ->
{Acc2, PS};
Error ->
debug(PS, {cache, {clear, Error}}),
ok = clear_cache(Archive, Cache),
debug(PS, {cache, Error}),
erase(Archive),
%% put(Archive, {Error, FI}),
{Error, PS}
end;
Error ->
debug(PS, {cache, Error}),
{Error, PS}
end;
Error ->
debug(PS, {cache, {clear, Error}}),
ok = clear_cache(Archive, Cache),
apply_archive(PS, Fun, Acc, Archive)
end
end.
open_archive(Archive, Acc, Fun) ->
case prim_file:read_file_info(Archive) of
{ok, FileInfo} ->
open_archive(Archive, FileInfo, Acc, Fun);
{error, Reason} ->
{error, Reason}
end.
open_archive(Archive, FileInfo, Acc, Fun) ->
FakeFI = FileInfo#file_info{type = directory},
Wrapper =
fun({N, GI, GB}, {A, I, FunnyDirs}) -> % Full iteration at open
Funny = funny_split(N, $/),
FunnyDirs2 =
case Funny of
["" | FunnyDir] ->
[FunnyDir | FunnyDirs];
_ ->
FunnyDirs
end,
{Includes, FunnyDirs3, A2} =
ensure_virtual_dirs(Funny, Fun, FakeFI, [{true, Funny}], FunnyDirs2, A),
{_Continue, A3} = Fun({Funny, GI, GB}, A2),
{true, Includes, {A3, I, FunnyDirs3}}
end,
prim_zip:open(Wrapper, {Acc, FakeFI, []}, Archive).
ensure_virtual_dirs(Funny, Fun, FakeFI, Includes, FunnyDirs, Acc) ->
case Funny of
[_] ->
{Includes, FunnyDirs, Acc};
[_ | FunnyDir] ->
case lists:member(FunnyDir, FunnyDirs) of % BIF
false ->
GetInfo = fun() -> FakeFI end,
GetBin = fun() -> <<>> end,
VirtualDir = ["" | FunnyDir],
Includes2 = [{true, VirtualDir, GetInfo, GetBin} | Includes],
FunnyDirs2 = [FunnyDir | FunnyDirs],
{I, F, Acc2} = ensure_virtual_dirs(FunnyDir, Fun, FakeFI, Includes2, FunnyDirs2, Acc),
{_Continue, Acc3} = Fun({VirtualDir, GetInfo, GetBin}, Acc2),
{I, F, Acc3};
true ->
ensure_virtual_dirs(FunnyDir,Fun,FakeFI,Includes,FunnyDirs,Acc)
end
end.
foldl_archive(PrimZip, Acc, Fun) ->
Wrapper =
fun({Funny, GI, GB}, A) ->
%% Allow partial iteration at foldl
{Continue, A2} = Fun({Funny, GI, GB}, A),
{Continue, true, A2}
end,
prim_zip:foldl(Wrapper, Acc, PrimZip).
cache_new(PS) ->
PS.
clear_cache(Archive, Cache) ->
erase(Archive),
case Cache of
{ok, PrimZip} ->
prim_zip:close(PrimZip);
{error, _} ->
ok
end.
%%% --------------------------------------------------------
%%% Misc. functions.
%%% --------------------------------------------------------
%%% Look for directory separators
is_basename(File) ->
case deep_member($/, File) of
true ->
false;
false ->
case erlang:system_info(os_type) of
{win32, _} ->
case File of
[_,$: | _] ->
false;
_ ->
not deep_member($\\, File)
end;
_ ->
true
end
end.
send_all(U, [IP | AL], Cmd) ->
?dbg(sendto, {U, IP, ?EBOOT_PORT, Cmd}),
prim_inet:sendto(U, IP, ?EBOOT_PORT, Cmd),
send_all(U, AL, Cmd);
send_all(_U, [], _) -> ok.
join(P, F) ->
P ++ "/" ++ F.
member(X, [X|_]) -> true;
member(X, [_|Y]) -> member(X, Y);
member(_X, []) -> false.
deep_member(X, [X|_]) ->
true;
deep_member(X, [List | Y]) when is_list(List) ->
deep_member(X, List) orelse deep_member(X, Y);
deep_member(X, [Atom | Y]) when is_atom(Atom) ->
deep_member(X, atom_to_list(Atom)) orelse deep_member(X, Y);
deep_member(X, [_ | Y]) ->
deep_member(X, Y);
deep_member(_X, []) ->
false.
keymember(X, I, [Y | _]) when element(I,Y) =:= X -> true;
keymember(X, I, [_ | T]) -> keymember(X, I, T);
keymember(_X, _I, []) -> false.
keysort(I, L) -> keysort(I, L, []).
keysort(I, [X | L], Ls) ->
keysort(I, L, keyins(X, I, Ls));
keysort(_I, [], Ls) -> Ls.
keyins(X, I, [Y | T]) when X < element(I,Y) -> [X,Y|T];
keyins(X, I, [Y | T]) -> [Y | keyins(X, I, T)];
keyins(X, _I, []) -> [X].
to_strs([P|Paths]) when is_atom(P) ->
[atom_to_list(P)|to_strs(Paths)];
to_strs([P|Paths]) when is_list(P) ->
[P|to_strs(Paths)];
to_strs([_|Paths]) ->
to_strs(Paths);
to_strs([]) ->
[].
reverse([] = L) ->
L;
reverse([_] = L) ->
L;
reverse([A, B]) ->
[B, A];
reverse([A, B | L]) ->
lists:reverse(L, [B, A]). % BIF
%% Returns all lists in reverse order
funny_split(List, Sep) ->
funny_split(List, Sep, [], []).
funny_split([Sep | Tail], Sep, Path, Paths) ->
funny_split(Tail, Sep, [], [Path | Paths]);
funny_split([Head | Tail], Sep, Path, Paths) ->
funny_split(Tail, Sep, [Head | Path], Paths);
funny_split([], _Sep, Path, Paths) ->
[Path | Paths].
name_split(ArchiveFile, File0) ->
File = absname(File0),
do_name_split(ArchiveFile, File).
do_name_split(undefined, File) ->
%% Ignore primary archive
case string_split(File, init:archive_extension(), []) of
no_split ->
%% Plain file
{file, File};
{split, _RevArchiveBase, RevArchiveFile, []} ->
%% Top dir in archive
ArchiveFile = reverse(RevArchiveFile),
{archive, ArchiveFile, []};
{split, _RevArchiveBase, RevArchiveFile, [$/ | FileInArchive]} ->
%% File in archive
ArchiveFile = reverse(RevArchiveFile),
{archive, ArchiveFile, FileInArchive};
{split, _RevArchiveBase, _RevArchiveFile, _FileInArchive} ->
%% False match. Assume plain file
{file, File}
end;
do_name_split(ArchiveFile, File) ->
%% Look first in primary archive
case string_match(File, ArchiveFile, []) of
no_match ->
%% Archive or plain file
do_name_split(undefined, File);
{match, _RevPrimArchiveFile, FileInArchive} ->
%% Primary archive
{archive, ArchiveFile, FileInArchive}
end.
string_match([Char | File], [Char | Archive], RevTop) ->
string_match(File, Archive, [Char | RevTop]);
string_match([] = File, [], RevTop) ->
{match, RevTop, File};
string_match([$/ | File], [], RevTop) ->
{match, RevTop, File};
string_match(_File, _Archive, _RevTop) ->
no_match.
string_split([Char | File], [Char | Ext] = FullExt, RevTop) ->
RevTop2 = [Char | RevTop],
string_split2(File, Ext, RevTop, RevTop2, File, FullExt, RevTop2);
string_split([Char | File], Ext, RevTop) ->
string_split(File, Ext, [Char | RevTop]);
string_split([], _Ext, _RevTop) ->
no_split.
string_split2([Char | File], [Char | Ext], RevBase, RevTop, SaveFile, SaveExt, SaveTop) ->
string_split2(File, Ext, RevBase, [Char | RevTop], SaveFile, SaveExt, SaveTop);
string_split2(File, [], RevBase, RevTop, _SaveFile, _SaveExt, _SaveTop) ->
{split, RevBase, RevTop, File};
string_split2(_, _Ext, _RevBase, _RevTop, SaveFile, SaveExt, SaveTop) ->
string_split(SaveFile, SaveExt, SaveTop).
%% Parse list of ipv4 addresses
ipv4_list([H | T]) ->
IPV = if is_atom(H) -> ipv4_address(atom_to_list(H));
is_list(H) -> ipv4_address(H);
true -> {error,einal}
end,
case IPV of
{ok,IP} -> [IP | ipv4_list(T)];
_ -> ipv4_list(T)
end;
ipv4_list([]) -> [].
%%
%% Parse Ipv4 address: d1.d2.d3.d4 (from inet_parse)
%%
%% Return {ok, IP} | {error, einval}
%%
ipv4_address(Cs) ->
case catch ipv4_addr(Cs, []) of
{'EXIT',_} -> {error,einval};
Addr -> {ok,Addr}
end.
ipv4_addr([C | Cs], IP) when C >= $0, C =< $9 -> ipv4_addr(Cs, C-$0, IP).
ipv4_addr([$.|Cs], N, IP) when N < 256 -> ipv4_addr(Cs, [N|IP]);
ipv4_addr([C|Cs], N, IP) when C >= $0, C =< $9 ->
ipv4_addr(Cs, N*10 + (C-$0), IP);
ipv4_addr([], D, [C,B,A]) when D < 256 -> {A,B,C,D}.
%% A simplified version of filename:absname/1
absname(Name) ->
Name2 = normalize(Name, []),
Name3 =
case pathtype(Name2) of
absolute ->
Name2;
relative ->
case prim_file:get_cwd() of
{ok, Cwd} ->
Cwd ++ "/" ++ Name2;
{error, _} ->
Name2
end;
volumerelative ->
case prim_file:get_cwd() of
{ok, Cwd} ->
absname_vr(Name2, Cwd);
{error, _} ->
Name2
end
end,
path_flatten(Name3).
%% Assumes normalized name
absname_vr([$/ | NameRest], [Drive, $\: | _]) ->
%% Absolute path on current drive.
[Drive, $\: | NameRest];
absname_vr([Drive, $\: | NameRest], [Drive, $\: | _] = Cwd) ->
%% Relative to current directory on current drive.
Cwd ++ "/" ++ NameRest;
absname_vr([Drive, $\: | NameRest], _) ->
%% Relative to current directory on another drive.
case prim_file:get_cwd([Drive, $\:]) of
{ok, DriveCwd} ->
DriveCwd ++ "/" ++ NameRest;
{error, _} ->
[Drive, $\:, $/] ++ NameRest
end.
%% Assumes normalized name
pathtype(Name) when is_list(Name) ->
case erlang:system_info(os_type) of
{unix, _} ->
unix_pathtype(Name);
{win32, _} ->
win32_pathtype(Name);
{vxworks, _} ->
case vxworks_first(Name) of
{device, _Rest, _Dev} ->
absolute;
_ ->
relative
end
end.
unix_pathtype(Name) ->
case Name of
[$/|_] ->
absolute;
[List|Rest] when is_list(List) ->
unix_pathtype(List++Rest);
[Atom|Rest] when is_atom(Atom) ->
atom_to_list(Atom)++Rest;
_ ->
relative
end.
win32_pathtype(Name) ->
case Name of
[List|Rest] when is_list(List) ->
win32_pathtype(List++Rest);
[Atom|Rest] when is_atom(Atom) ->
win32_pathtype(atom_to_list(Atom)++Rest);
[Char, List | Rest] when is_list(List) ->
win32_pathtype([Char | List++Rest]);
[$/, $/|_] ->
absolute;
[$/|_] ->
volumerelative;
[C1, C2, List | Rest] when is_list(List) ->
win32_pathtype([C1, C2|List ++ Rest]);
[_Letter, $:, $/|_] ->
absolute;
[_Letter, $:|_] ->
volumerelative;
_ ->
relative
end.
vxworks_first(Name) ->
case Name of
[] ->
{not_device, [], []};
[$/ | T] ->
vxworks_first2(device, T, [$/]);
[H | T] when is_list(H) ->
vxworks_first(H ++ T);
[H | T] ->
vxworks_first2(not_device, T, [H])
end.
vxworks_first2(Devicep, Name, FirstComp) ->
case Name of
[] ->
{Devicep, [], FirstComp};
[$/ |T ] ->
{Devicep, [$/ | T], FirstComp};
[$: | T]->
{device, T, [$: | FirstComp]};
[H | T] when is_list(H) ->
vxworks_first2(Devicep, H ++ T, FirstComp);
[H | T] ->
vxworks_first2(Devicep, T, [H | FirstComp])
end.
normalize(Name, Acc) ->
case Name of
[List | Rest] when is_list(List) ->
normalize(List ++ Rest, Acc);
[Atom | Rest] when is_atom(Atom) ->
normalize(atom_to_list(Atom) ++ Rest, Acc);
[$\\ | Chars] ->
normalize(Chars, [$/ | Acc]);
[Char | Chars] ->
normalize(Chars, [Char | Acc]);
[] ->
reverse(Acc)
end.
%% Remove .. and . from the path, e.g.
%% /path/./to/this/../file -> /path/to/file
path_flatten(Name) ->
path_flatten(Name,[],[]).
path_flatten([$/,$.,$.,$/|Rest],_RevLast,RevTop) ->
path_flatten(Rest,[],RevTop);
path_flatten([$/,$.,$/|Rest],RevLast,RevTop) ->
path_flatten([$/|Rest],RevLast,RevTop);
path_flatten([$/,$.,$.],_RevLast,RevTop) ->
path_flatten([],[],RevTop);
path_flatten([$/,$.],RevLast,RevTop) ->
path_flatten([],RevLast,RevTop);
path_flatten([$/],RevLast,RevTop) ->
path_flatten([],RevLast,RevTop);
path_flatten([$/|Rest],RevLast,RevTop) ->
path_flatten(Rest,[],[$/|RevLast++RevTop]);
path_flatten([Ch|Rest],RevLast,RevTop) ->
path_flatten(Rest,[Ch|RevLast],RevTop);
path_flatten([],RevLast,RevTop) ->
reverse(RevLast++RevTop).
