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-rw-r--r--lib/kernel/src/os.erl258
1 files changed, 86 insertions, 172 deletions
diff --git a/lib/kernel/src/os.erl b/lib/kernel/src/os.erl
index ded03361ee..f0ad26b1f2 100644
--- a/lib/kernel/src/os.erl
+++ b/lib/kernel/src/os.erl
@@ -1,18 +1,19 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2016. 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/.
+%% Licensed 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
%%
-%% 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.
+%% 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.
%%
%% %CopyrightEnd%
%%
@@ -26,7 +27,10 @@
%%% BIFs
--export([getenv/0, getenv/1, getpid/0, putenv/2, timestamp/0]).
+-export([getenv/0, getenv/1, getenv/2, getpid/0,
+ perf_counter/0, perf_counter/1,
+ putenv/2, system_time/0, system_time/1,
+ timestamp/0, unsetenv/1]).
-spec getenv() -> [string()].
@@ -39,12 +43,37 @@ getenv() -> erlang:nif_error(undef).
getenv(_) ->
erlang:nif_error(undef).
+-spec getenv(VarName, DefaultValue) -> Value when
+ VarName :: string(),
+ DefaultValue :: string(),
+ Value :: string().
+
+getenv(VarName, DefaultValue) ->
+ case os:getenv(VarName) of
+ false ->
+ DefaultValue;
+ Value ->
+ Value
+ end.
+
-spec getpid() -> Value when
Value :: string().
getpid() ->
erlang:nif_error(undef).
+-spec perf_counter() -> Counter when
+ Counter :: integer().
+
+perf_counter() ->
+ erlang:nif_error(undef).
+
+-spec perf_counter(Unit) -> integer() when
+ Unit :: erlang:time_unit().
+
+perf_counter(Unit) ->
+ erlang:convert_time_unit(os:perf_counter(), perf_counter, Unit).
+
-spec putenv(VarName, Value) -> true when
VarName :: string(),
Value :: string().
@@ -52,12 +81,29 @@ getpid() ->
putenv(_, _) ->
erlang:nif_error(undef).
+-spec system_time() -> integer().
+
+system_time() ->
+ erlang:nif_error(undef).
+
+-spec system_time(Unit) -> integer() when
+ Unit :: erlang:time_unit().
+
+system_time(_Unit) ->
+ erlang:nif_error(undef).
+
-spec timestamp() -> Timestamp when
Timestamp :: erlang:timestamp().
timestamp() ->
erlang:nif_error(undef).
+-spec unsetenv(VarName) -> true when
+ VarName :: string().
+
+unsetenv(_) ->
+ erlang:nif_error(undef).
+
%%% End of BIFs
-spec type() -> {Osfamily, Osname} when
@@ -79,10 +125,7 @@ version() ->
Name :: string(),
Filename :: string().
find_executable(Name) ->
- case os:getenv("PATH") of
- false -> find_executable(Name, []);
- Path -> find_executable(Name, Path)
- end.
+ find_executable(Name, os:getenv("PATH", "")).
-spec find_executable(Name, Path) -> Filename | 'false' when
Name :: string(),
@@ -183,169 +226,40 @@ extensions() ->
Command :: atom() | io_lib:chars().
cmd(Cmd) ->
validate(Cmd),
- case type() of
- {unix, _} ->
- unix_cmd(Cmd);
- {win32, Wtype} ->
- Command0 = case {os:getenv("COMSPEC"),Wtype} of
- {false,windows} -> lists:concat(["command.com /c", Cmd]);
- {false,_} -> lists:concat(["cmd /c", Cmd]);
- {Cspec,_} -> lists:concat([Cspec," /c",Cmd])
- end,
- %% open_port/2 awaits string() in Command, but io_lib:chars() can be
- %% deep lists according to io_lib module description.
- Command = lists:flatten(Command0),
- Port = open_port({spawn, Command}, [stream, in, eof, hide]),
- get_data(Port, [])
- end.
-
-unix_cmd(Cmd) ->
- Tag = make_ref(),
- {Pid,Mref} = erlang:spawn_monitor(
- fun() ->
- process_flag(trap_exit, true),
- Port = start_port(),
- erlang:port_command(Port, mk_cmd(Cmd)),
- exit({Tag,unix_get_data(Port)})
- end),
- receive
- {'DOWN',Mref,_,Pid,{Tag,Result}} ->
- Result;
- {'DOWN',Mref,_,Pid,Reason} ->
- exit(Reason)
- end.
-
-%% The -s flag implies that only the positional parameters are set,
-%% and the commands are read from standard input. We set the
-%% $1 parameter for easy identification of the resident shell.
-%%
--define(SHELL, "/bin/sh -s unix:cmd 2>&1").
--define(PORT_CREATOR_NAME, os_cmd_port_creator).
-
-%%
-%% Serializing open_port through a process to avoid smp lock contention
-%% when many concurrent os:cmd() want to do vfork (OTP-7890).
-%%
--spec start_port() -> port().
-start_port() ->
- Ref = make_ref(),
- Request = {Ref,self()},
- {Pid, Mon} = case whereis(?PORT_CREATOR_NAME) of
- undefined ->
- spawn_monitor(fun() ->
- start_port_srv(Request)
- end);
- P ->
- P ! Request,
- M = erlang:monitor(process, P),
- {P, M}
- end,
- receive
- {Ref, Port} when is_port(Port) ->
- erlang:demonitor(Mon, [flush]),
- Port;
- {Ref, Error} ->
- erlang:demonitor(Mon, [flush]),
- exit(Error);
- {'DOWN', Mon, process, Pid, _Reason} ->
- start_port()
- end.
-
-start_port_srv(Request) ->
- %% We don't want a group leader of some random application. Use
- %% kernel_sup's group leader.
- {group_leader, GL} = process_info(whereis(kernel_sup),
- group_leader),
- true = group_leader(GL, self()),
- process_flag(trap_exit, true),
- StayAlive = try register(?PORT_CREATOR_NAME, self())
- catch
- error:_ -> false
- end,
- start_port_srv_handle(Request),
- case StayAlive of
- true -> start_port_srv_loop();
- false -> exiting
+ {SpawnCmd, SpawnOpts, SpawnInput} = mk_cmd(os:type(), Cmd),
+ Port = open_port({spawn, SpawnCmd}, [binary, stderr_to_stdout,
+ stream, in, eof, hide | SpawnOpts]),
+ true = port_command(Port, SpawnInput),
+ Bytes = get_data(Port, []),
+ String = unicode:characters_to_list(Bytes),
+ if %% Convert to unicode list if possible otherwise return bytes
+ is_list(String) -> String;
+ true -> binary_to_list(Bytes)
end.
-start_port_srv_handle({Ref,Client}) ->
- Reply = try open_port({spawn, ?SHELL},[stream]) of
- Port when is_port(Port) ->
- (catch port_connect(Port, Client)),
- unlink(Port),
- Port
- catch
- error:Reason ->
- {Reason,erlang:get_stacktrace()}
- end,
- Client ! {Ref,Reply}.
-
-
-start_port_srv_loop() ->
- receive
- {Ref, Client} = Request when is_reference(Ref),
- is_pid(Client) ->
- start_port_srv_handle(Request);
- _Junk ->
- ignore
- end,
- start_port_srv_loop().
-
-%%
-%% unix_get_data(Port) -> Result
-%%
-unix_get_data(Port) ->
- unix_get_data(Port, []).
-
-unix_get_data(Port, Sofar) ->
- receive
- {Port,{data, Bytes}} ->
- case eot(Bytes) of
- {done, Last} ->
- lists:flatten([Sofar|Last]);
- more ->
- unix_get_data(Port, [Sofar|Bytes])
- end;
- {'EXIT', Port, _} ->
- lists:flatten(Sofar)
- end.
-
-%%
-%% eot(String) -> more | {done, Result}
-%%
-eot(Bs) ->
- eot(Bs, []).
-
-eot([4| _Bs], As) ->
- {done, lists:reverse(As)};
-eot([B| Bs], As) ->
- eot(Bs, [B| As]);
-eot([], _As) ->
- more.
-
-%%
-%% mk_cmd(Cmd) -> {ok, ShellCommandString} | {error, ErrorString}
-%%
-%% We do not allow any input to Cmd (hence commands that want
-%% to read from standard input will return immediately).
-%% Standard error is redirected to standard output.
-%%
-%% We use ^D (= EOT = 4) to mark the end of the stream.
-%%
-mk_cmd(Cmd) when is_atom(Cmd) -> % backward comp.
- mk_cmd(atom_to_list(Cmd));
-mk_cmd(Cmd) ->
- %% We insert a new line after the command, in case the command
- %% contains a comment character.
- io_lib:format("(~ts\n) </dev/null; echo \"\^D\"\n", [Cmd]).
-
+mk_cmd({win32,Wtype}, Cmd) ->
+ Command = case {os:getenv("COMSPEC"),Wtype} of
+ {false,windows} -> lists:concat(["command.com /c", Cmd]);
+ {false,_} -> lists:concat(["cmd /c", Cmd]);
+ {Cspec,_} -> lists:concat([Cspec," /c",Cmd])
+ end,
+ {Command, [], []};
+mk_cmd(OsType,Cmd) when is_atom(Cmd) ->
+ mk_cmd(OsType, atom_to_list(Cmd));
+mk_cmd(_,Cmd) ->
+ %% Have to send command in like this in order to make sh commands like
+ %% cd and ulimit available
+ {"/bin/sh -s unix:cmd", [out],
+ %% We insert a new line after the command, in case the command
+ %% contains a comment character.
+ ["(", unicode:characters_to_binary(Cmd), "\n); exit\n"]}.
validate(Atom) when is_atom(Atom) ->
ok;
validate(List) when is_list(List) ->
validate1(List).
-validate1([C|Rest]) when is_integer(C), 0 =< C, C < 256 ->
+validate1([C|Rest]) when is_integer(C) ->
validate1(Rest);
validate1([List|Rest]) when is_list(List) ->
validate1(List),
@@ -356,7 +270,7 @@ validate1([]) ->
get_data(Port, Sofar) ->
receive
{Port, {data, Bytes}} ->
- get_data(Port, [Sofar|Bytes]);
+ get_data(Port, [Sofar,Bytes]);
{Port, eof} ->
Port ! {self(), close},
receive
@@ -369,5 +283,5 @@ get_data(Port, Sofar) ->
after 1 -> % force context switch
ok
end,
- lists:flatten(Sofar)
+ iolist_to_binary(Sofar)
end.