%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2010. 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%
%%
%%
%% New initial version of init.
%% Booting from a script. The script is fetched either from
%% a local file or distributed from another erlang node.
%%
%% Flags:
%% -id Identity : identity of the system.
%% -boot File : Absolute file name of the boot script.
%% -boot_var Var Value
%% : $Var in the boot script is expanded to
%% Value.
%% -loader LoaderMethod
%% : efile, inet, ose_inet
%% (Optional - default efile)
%% -hosts [Node] : List of hosts from which we can boot.
%% (Mandatory if -loader inet or ose_inet)
%% -mode embedded : Load all modules at startup, no automatic loading
%% -mode interactive : Auto load modules (default system behaviour).
%% -path : Override path in bootfile.
%% -pa Path+ : Add my own paths first.
%% -pz Path+ : Add my own paths last.
%% -run : Start own processes.
%% -s : Start own processes.
%%
%% Experimental flags:
%% -init_debug : Activate debug printouts in init
%% -loader_debug : Activate debug printouts in erl_prim_loader
%% -code_path_choice : strict | relaxed
-module(init).
-export([restart/0,reboot/0,stop/0,stop/1,
get_status/0,boot/1,get_arguments/0,get_plain_arguments/0,
get_argument/1,script_id/0]).
%% for the on_load functionality; not for general use
-export([run_on_load_handlers/0]).
%% internal exports
-export([fetch_loaded/0,ensure_loaded/1,make_permanent/2,
notify_when_started/1,wait_until_started/0,
objfile_extension/0, archive_extension/0,code_path_choice/0]).
-include_lib("kernel/include/file.hrl").
-type internal_status() :: 'starting' | 'started' | 'stopping'.
-record(state, {flags = [],
args = [],
start = [],
kernel = [] :: [{atom(), pid()}],
bootpid :: pid(),
status = {starting, starting} :: {internal_status(), term()},
script_id = [],
loaded = [],
subscribed = []}).
-type state() :: #state{}.
-define(ON_LOAD_HANDLER, init__boot__on_load_handler).
debug(false, _) -> ok;
debug(_, T) -> erlang:display(T).
-spec get_arguments() -> [{atom(), [string()]}].
get_arguments() ->
request(get_arguments).
-spec get_plain_arguments() -> [string()].
get_plain_arguments() ->
bs2ss(request(get_plain_arguments)).
-spec get_argument(atom()) -> 'error' | {'ok', [[string()]]}.
get_argument(Arg) ->
request({get_argument, Arg}).
-spec script_id() -> term().
script_id() ->
request(script_id).
bs2as(L0) when is_list(L0) ->
map(fun b2a/1, L0);
bs2as(L) ->
L.
bs2ss(L0) when is_list(L0) ->
map(fun b2s/1, L0);
bs2ss(L) ->
L.
-spec get_status() -> {internal_status(), term()}.
get_status() ->
request(get_status).
-spec fetch_loaded() -> [atom()].
fetch_loaded() ->
request(fetch_loaded).
%% Handle dynamic code loading until the
%% real code_server has been started.
-spec ensure_loaded(atom()) -> 'not_allowed' | {'module', atom()}.
ensure_loaded(Module) ->
request({ensure_loaded, Module}).
-spec make_permanent(file:filename(), 'false' | file:filename()) ->
'ok' | {'error', term()}.
make_permanent(Boot,Config) ->
request({make_permanent,Boot,Config}).
-spec notify_when_started(pid()) -> 'ok' | 'started'.
notify_when_started(Pid) ->
request({notify_when_started,Pid}).
-spec wait_until_started() -> 'ok'.
wait_until_started() ->
receive
{init,started} -> ok
end.
request(Req) ->
init ! {self(),Req},
receive
{init,Rep} ->
Rep
end.
-spec restart() -> 'ok'.
restart() -> init ! {stop,restart}, ok.
-spec reboot() -> 'ok'.
reboot() -> init ! {stop,reboot}, ok.
-spec stop() -> 'ok'.
stop() -> init ! {stop,stop}, ok.
-spec stop(non_neg_integer() | string()) -> 'ok'.
stop(Status) -> init ! {stop,{stop,Status}}, ok.
-spec boot([binary()]) -> no_return().
boot(BootArgs) ->
register(init, self()),
process_flag(trap_exit, true),
start_on_load_handler_process(),
{Start0,Flags,Args} = parse_boot_args(BootArgs),
Start = map(fun prepare_run_args/1, Start0),
Flags0 = flags_to_atoms_again(Flags),
boot(Start,Flags0,Args).
prepare_run_args({eval, [Expr]}) ->
{eval,Expr};
prepare_run_args({_, L=[]}) ->
bs2as(L);
prepare_run_args({_, L=[_]}) ->
bs2as(L);
prepare_run_args({s, [M,F|Args]}) ->
[b2a(M), b2a(F) | bs2as(Args)];
prepare_run_args({run, [M,F|Args]}) ->
[b2a(M), b2a(F) | bs2ss(Args)].
b2a(Bin) when is_binary(Bin) ->
list_to_atom(binary_to_list(Bin));
b2a(A) when is_atom(A) ->
A.
b2s(Bin) when is_binary(Bin) ->
binary_to_list(Bin);
b2s(L) when is_list(L) ->
L.
map(_F, []) ->
[];
map(F, [X|Rest]) ->
[F(X) | map(F, Rest)].
flags_to_atoms_again([]) ->
[];
flags_to_atoms_again([{F0,L0}|Rest]) ->
L = L0,
F = b2a(F0),
[{F,L}|flags_to_atoms_again(Rest)];
flags_to_atoms_again([{F0}|Rest]) ->
F = b2a(F0),
[{F}|flags_to_atoms_again(Rest)].
-spec code_path_choice() -> 'relaxed' | 'strict'.
code_path_choice() ->
case get_argument(code_path_choice) of
{ok,[["strict"]]} ->
strict;
{ok,[["relaxed"]]} ->
relaxed;
_Else ->
relaxed
end.
boot(Start,Flags,Args) ->
BootPid = do_boot(Flags,Start),
State = #state{flags = Flags,
args = Args,
start = Start,
bootpid = BootPid},
boot_loop(BootPid,State).
%%% Convert a term to a printable string, if possible.
to_string(X) when is_list(X) -> % assume string
F = flatten(X, []),
case printable_list(F) of
true -> F;
false -> ""
end;
to_string(X) when is_atom(X) ->
atom_to_list(X);
to_string(X) when is_pid(X) ->
pid_to_list(X);
to_string(X) when is_float(X) ->
float_to_list(X);
to_string(X) when is_integer(X) ->
integer_to_list(X);
to_string(_X) ->
"". % can't do anything with it
%% This is an incorrect and narrow definition of printable characters.
%% The correct one is in io_lib:printable_list/1
%%
printable_list([H|T]) when is_integer(H), H >= 32, H =< 126 ->
printable_list(T);
printable_list([$\n|T]) -> printable_list(T);
printable_list([$\r|T]) -> printable_list(T);
printable_list([$\t|T]) -> printable_list(T);
printable_list([]) -> true;
printable_list(_) -> false.
flatten([H|T], Tail) when is_list(H) ->
flatten(H, flatten(T, Tail));
flatten([H|T], Tail) ->
[H|flatten(T, Tail)];
flatten([], Tail) ->
Tail.
things_to_string([X|Rest]) ->
" (" ++ to_string(X) ++ ")" ++ things_to_string(Rest);
things_to_string([]) ->
"".
halt_string(String, List) ->
HaltString = String ++ things_to_string(List),
if
length(HaltString)<199 -> HaltString;
true -> first198(HaltString, 198)
end.
first198([H|T], N) when N>0 ->
[H|first198(T, N-1)];
first198(_, 0) ->
[].
%% String = string()
%% List = [string() | atom() | pid() | number()]
%% Any other items in List, such as tuples, are ignored when creating
%% the string used as argument to erlang:halt/1.
crash(String, List) ->
halt(halt_string(String, List)).
%% Status is {InternalStatus,ProvidedStatus}
-spec boot_loop(pid(), state()) -> no_return().
boot_loop(BootPid, State) ->
receive
{BootPid,loaded,ModLoaded} ->
Loaded = State#state.loaded,
boot_loop(BootPid,State#state{loaded = [ModLoaded|Loaded]});
{BootPid,started,KernelPid} ->
boot_loop(BootPid, new_kernelpid(KernelPid, BootPid, State));
{BootPid,progress,started} ->
{InS,_} = State#state.status,
notify(State#state.subscribed),
boot_loop(BootPid,State#state{status = {InS,started},
subscribed = []});
{BootPid,progress,NewStatus} ->
{InS,_} = State#state.status,
boot_loop(BootPid,State#state{status = {InS,NewStatus}});
{BootPid,{script_id,Id}} ->
boot_loop(BootPid,State#state{script_id = Id});
{'EXIT',BootPid,normal} ->
{_,PS} = State#state.status,
notify(State#state.subscribed),
loop(State#state{status = {started,PS},
subscribed = []});
{'EXIT',BootPid,Reason} ->
erlang:display({"init terminating in do_boot",Reason}),
crash("init terminating in do_boot", [Reason]);
{'EXIT',Pid,Reason} ->
Kernel = State#state.kernel,
terminate(Pid,Kernel,Reason), %% If Pid is a Kernel pid, halt()!
boot_loop(BootPid,State);
{stop,Reason} ->
stop(Reason,State);
{From,fetch_loaded} -> %% Fetch and reset initially loaded modules.
From ! {init,State#state.loaded},
garb_boot_loop(BootPid,State#state{loaded = []});
{From,{ensure_loaded,Module}} ->
{Res, Loaded} = ensure_loaded(Module, State#state.loaded),
From ! {init,Res},
boot_loop(BootPid,State#state{loaded = Loaded});
Msg ->
boot_loop(BootPid,handle_msg(Msg,State))
end.
ensure_loaded(Module, Loaded) ->
File = concat([Module,objfile_extension()]),
case catch load_mod(Module,File) of
{ok, FullName} ->
{{module, Module}, [{Module, FullName}|Loaded]};
Res ->
{Res, Loaded}
end.
%% Tell subscribed processes the system has started.
notify(Pids) ->
lists:foreach(fun(Pid) -> Pid ! {init,started} end, Pids).
%% Garbage collect all info about initially loaded modules.
%% This information is temporary stored until the code_server
%% is started.
%% We force the garbage collection as the init process holds
%% this information during the initialisation of the system and
%% it will be automatically garbed much later (perhaps not at all
%% if it is not accessed much).
garb_boot_loop(BootPid,State) ->
garbage_collect(),
boot_loop(BootPid,State).
new_kernelpid({Name,{ok,Pid}},BootPid,State) when is_pid(Pid) ->
link(Pid),
BootPid ! {self(),ok,Pid},
Kernel = State#state.kernel,
State#state{kernel = [{Name,Pid}|Kernel]};
new_kernelpid({_Name,ignore},BootPid,State) ->
BootPid ! {self(),ignore},
State;
new_kernelpid({Name,What},BootPid,State) ->
erlang:display({"could not start kernel pid",Name,What}),
clear_system(BootPid,State),
crash("could not start kernel pid", [Name, What]).
%% Here is the main loop after the system has booted.
loop(State) ->
receive
{'EXIT',Pid,Reason} ->
Kernel = State#state.kernel,
terminate(Pid,Kernel,Reason), %% If Pid is a Kernel pid, halt()!
loop(State);
{stop,Reason} ->
stop(Reason,State);
{From,fetch_loaded} -> %% The Loaded info is cleared in
Loaded = State#state.loaded, %% boot_loop but is handled here
From ! {init,Loaded}, %% anyway.
loop(State);
{From, {ensure_loaded, _}} ->
From ! {init, not_allowed},
loop(State);
Msg ->
loop(handle_msg(Msg,State))
end.
handle_msg(Msg,State0) ->
case catch do_handle_msg(Msg,State0) of
{new_state,State} -> State;
_ -> State0
end.
do_handle_msg(Msg,State) ->
#state{flags = Flags,
status = Status,
script_id = Sid,
args = Args,
subscribed = Subscribed} = State,
case Msg of
{From,get_plain_arguments} ->
From ! {init,Args};
{From,get_arguments} ->
From ! {init,get_arguments(Flags)};
{From,{get_argument,Arg}} ->
From ! {init,get_argument(Arg,Flags)};
{From,get_status} ->
From ! {init,Status};
{From,script_id} ->
From ! {init,Sid};
{From,{make_permanent,Boot,Config}} ->
{Res,State1} = make_permanent(Boot,Config,Flags,State),
From ! {init,Res},
{new_state,State1};
{From,{notify_when_started,Pid}} ->
case Status of
{InS,PS} when InS =:= started ; PS =:= started ->
From ! {init,started};
_ ->
From ! {init,ok},
{new_state,State#state{subscribed = [Pid|Subscribed]}}
end;
X ->
case whereis(user) of
undefined ->
catch error_logger ! {info, self(), {self(), X, []}};
User ->
User ! X,
ok
end
end.
%%% -------------------------------------------------
%%% A new release has been installed and made
%%% permanent.
%%% Both restart/0 and reboot/0 shall startup using
%%% the new release. reboot/0 uses new boot script
%%% and configuration file pointed out externally.
%%% In the restart case we have to set new -boot and
%%% -config arguments.
%%% -------------------------------------------------
make_permanent(Boot,Config,Flags0,State) ->
case set_flag('-boot',Boot,Flags0) of
{ok,Flags1} ->
case set_flag('-config',Config,Flags1) of
{ok,Flags} ->
{ok,State#state{flags = Flags}};
Error ->
{Error,State}
end;
Error ->
{Error,State}
end.
set_flag(_Flag,false,Flags) ->
{ok,Flags};
set_flag(Flag,Value,Flags) when is_list(Value) ->
case catch list_to_binary(Value) of
{'EXIT',_} ->
{error,badarg};
AValue ->
{ok,set_argument(Flags,Flag,AValue)}
end;
set_flag(_,_,_) ->
{error,badarg}.
%%% -------------------------------------------------
%%% Stop the system.
%%% Reason is: restart | reboot | stop
%%% According to reason terminate emulator or restart
%%% system using the same init process again.
%%% -------------------------------------------------
stop(Reason,State) ->
BootPid = State#state.bootpid,
{_,Progress} = State#state.status,
State1 = State#state{status = {stopping, Progress}},
clear_system(BootPid,State1),
do_stop(Reason,State1).
do_stop(restart,#state{start = Start, flags = Flags, args = Args}) ->
boot(Start,Flags,Args);
do_stop(reboot,_) ->
halt();
do_stop(stop,State) ->
stop_heart(State),
halt();
do_stop({stop,Status},State) ->
stop_heart(State),
halt(Status).
clear_system(BootPid,State) ->
Heart = get_heart(State#state.kernel),
shutdown_pids(Heart,BootPid,State),
unload(Heart).
stop_heart(State) ->
case get_heart(State#state.kernel) of
false ->
ok;
Pid ->
%% As heart survives a restart the Parent of heart is init.
BootPid = self(),
%% ignore timeout
shutdown_kernel_pid(Pid, BootPid, self(), State)
end.
shutdown_pids(Heart,BootPid,State) ->
Timer = shutdown_timer(State#state.flags),
catch shutdown(State#state.kernel,BootPid,Timer,State),
kill_all_pids(Heart), % Even the shutdown timer.
kill_all_ports(Heart),
flush_timout(Timer).
get_heart([{heart,Pid}|_Kernel]) -> Pid;
get_heart([_|Kernel]) -> get_heart(Kernel);
get_heart(_) -> false.
shutdown([{heart,_Pid}|Kernel],BootPid,Timer,State) ->
shutdown(Kernel, BootPid, Timer, State);
shutdown([{_Name,Pid}|Kernel],BootPid,Timer,State) ->
shutdown_kernel_pid(Pid, BootPid, Timer, State),
shutdown(Kernel,BootPid,Timer,State);
shutdown(_,_,_,_) ->
true.
%%
%% A kernel pid must handle the special case message
%% {'EXIT',Parent,Reason} and terminate upon it!
%%
shutdown_kernel_pid(Pid, BootPid, Timer, State) ->
Pid ! {'EXIT',BootPid,shutdown},
shutdown_loop(Pid, Timer, State, []).
%%
%% We have to handle init requests here in case a process
%% performs such a request and cannot shutdown (deadlock).
%% Keep all other EXIT messages in case it was another
%% kernel process. Resend these messages and handle later.
%%
shutdown_loop(Pid,Timer,State,Exits) ->
receive
{'EXIT',Pid,_} ->
resend(reverse(Exits)),
ok;
{Timer,timeout} ->
erlang:display({init,shutdown_timeout}),
throw(timeout);
{stop,_} ->
shutdown_loop(Pid,Timer,State,Exits);
{From,fetch_loaded} ->
From ! {init,State#state.loaded},
shutdown_loop(Pid,Timer,State,Exits);
{'EXIT',OtherP,Reason} ->
shutdown_loop(Pid,Timer,State,
[{'EXIT',OtherP,Reason}|Exits]);
Msg ->
State1 = handle_msg(Msg,State),
shutdown_loop(Pid,Timer,State1,Exits)
end.
resend([ExitMsg|Exits]) ->
self() ! ExitMsg,
resend(Exits);
resend(_) ->
ok.
%%
%% Kill all existing pids in the system (except init and heart).
kill_all_pids(Heart) ->
case get_pids(Heart) of
[] ->
ok;
Pids ->
kill_em(Pids),
kill_all_pids(Heart) % Continue until all are really killed.
end.
%% All except zombies.
alive_processes() ->
[P || P <- processes(), erlang:is_process_alive(P)].
get_pids(Heart) ->
Pids = alive_processes(),
delete(Heart,self(),Pids).
delete(Heart,Init,[Heart|Pids]) -> delete(Heart,Init,Pids);
delete(Heart,Init,[Init|Pids]) -> delete(Heart,Init,Pids);
delete(Heart,Init,[Pid|Pids]) -> [Pid|delete(Heart,Init,Pids)];
delete(_,_,[]) -> [].
kill_em([Pid|Pids]) ->
exit(Pid,kill),
kill_em(Pids);
kill_em([]) ->
ok.
%%
%% Kill all existing ports in the system (except the heart port),
%% i.e. ports still existing after all processes have been killed.
%%
%% System ports like the async driver port will nowadays be immortal;
%% therefore, it is ok to send them exit signals...
%%
kill_all_ports(Heart) ->
kill_all_ports(Heart,erlang:ports()).
kill_all_ports(Heart,[P|Ps]) ->
case erlang:port_info(P,connected) of
{connected,Heart} ->
kill_all_ports(Heart,Ps);
_ ->
exit(P,kill),
kill_all_ports(Heart,Ps)
end;
kill_all_ports(_,_) ->
ok.
unload(false) ->
do_unload(sub(erlang:pre_loaded(),erlang:loaded()));
unload(_) ->
do_unload(sub([heart|erlang:pre_loaded()],erlang:loaded())).
do_unload([M|Mods]) ->
catch erlang:purge_module(M),
catch erlang:delete_module(M),
catch erlang:purge_module(M),
do_unload(Mods);
do_unload([]) ->
ok.
sub([H|T],L) -> sub(T,del(H,L));
sub([],L) -> L.
del(Item, [Item|T]) -> T;
del(Item, [H|T]) -> [H|del(Item, T)];
del(_Item, []) -> [].
%%% -------------------------------------------------
%%% If the terminated Pid is one of the processes
%%% added to the Kernel, take down the system brutally.
%%% We are not sure that ANYTHING can work anymore,
%%% i.e. halt the system.
%%% Sleep awhile, it is thus possible for the
%%% error_logger (if it is still alive) to write errors
%%% using the simplest method.
%%% -------------------------------------------------
terminate(Pid,Kernel,Reason) ->
case kernel_pid(Pid,Kernel) of
{ok,Name} ->
sleep(500), %% Flush error printouts!
erlang:display({"Kernel pid terminated",Name,Reason}),
crash("Kernel pid terminated", [Name, Reason]);
_ ->
false
end.
kernel_pid(Pid,[{Name,Pid}|_]) ->
{ok,Name};
kernel_pid(Pid,[_|T]) ->
kernel_pid(Pid,T);
kernel_pid(_,_) ->
false.
sleep(T) -> receive after T -> ok end.
%%% -------------------------------------------------
%%% Start the loader.
%%% The loader shall run for ever!
%%% -------------------------------------------------
start_prim_loader(Init,Id,Pgm,Nodes,Path,{Pa,Pz}) ->
case erl_prim_loader:start(Id,Pgm,Nodes) of
{ok,Pid} when Path =:= false ->
InitPath = append(Pa,["."|Pz]),
erl_prim_loader:set_path(InitPath),
add_to_kernel(Init,Pid),
Pid;
{ok,Pid} ->
erl_prim_loader:set_path(Path),
add_to_kernel(Init,Pid),
Pid;
{error,Reason} ->
erlang:display({"cannot start loader",Reason}),
exit(Reason)
end.
add_to_kernel(Init,Pid) ->
Init ! {self(),started,{erl_prim_loader,{ok,Pid}}},
receive
{Init,ok,Pid} ->
unlink(Pid),
ok
end.
prim_load_flags(Flags) ->
PortPgm = get_flag('-loader',Flags,<<"efile">>),
Hosts = get_flag_list('-hosts', Flags, []),
Id = get_flag('-id',Flags,none),
Path = get_flag_list('-path',Flags,false),
{PortPgm, Hosts, Id, Path}.
%%% -------------------------------------------------
%%% The boot process fetches a boot script and loads
%%% all modules specified and starts spec. processes.
%%% Processes specified with -s or -run are finally started.
%%% -------------------------------------------------
do_boot(Flags,Start) ->
Self = self(),
spawn_link(fun() -> do_boot(Self,Flags,Start) end).
do_boot(Init,Flags,Start) ->
process_flag(trap_exit,true),
{Pgm0,Nodes,Id,Path} = prim_load_flags(Flags),
Root = b2s(get_flag('-root',Flags)),
PathFls = path_flags(Flags),
Pgm = b2s(Pgm0),
_Pid = start_prim_loader(Init,b2a(Id),Pgm,bs2as(Nodes),
bs2ss(Path),PathFls),
BootFile = bootfile(Flags,Root),
BootList = get_boot(BootFile,Root),
LoadMode = b2a(get_flag('-mode',Flags,false)),
Deb = b2a(get_flag('-init_debug',Flags,false)),
catch ?ON_LOAD_HANDLER ! {init_debug_flag,Deb},
BootVars = get_flag_args('-boot_var',Flags),
ParallelLoad =
(Pgm =:= "efile") and (erlang:system_info(thread_pool_size) > 0),
PathChoice = code_path_choice(),
eval_script(BootList,Init,PathFls,{Root,BootVars},Path,
{true,LoadMode,ParallelLoad},Deb,PathChoice),
%% To help identifying Purify windows that pop up,
%% print the node name into the Purify log.
(catch erlang:system_info({purify, "Node: " ++ atom_to_list(node())})),
start_em(Start).
bootfile(Flags,Root) ->
b2s(get_flag('-boot',Flags,concat([Root,"/bin/start"]))).
path_flags(Flags) ->
Pa = append(reverse(get_flag_args('-pa',Flags))),
Pz = append(get_flag_args('-pz',Flags)),
{bs2ss(Pa),bs2ss(Pz)}.
get_boot(BootFile0,Root) ->
BootFile = concat([BootFile0,".boot"]),
case get_boot(BootFile) of
{ok, CmdList} ->
CmdList;
not_found -> %% Check for default.
BootF = concat([Root,"/bin/",BootFile]),
case get_boot(BootF) of
{ok, CmdList} ->
CmdList;
not_found ->
exit({'cannot get bootfile',list_to_atom(BootFile)});
_ ->
exit({'bootfile format error',list_to_atom(BootF)})
end;
_ ->
exit({'bootfile format error',list_to_atom(BootFile)})
end.
get_boot(BootFile) ->
case erl_prim_loader:get_file(BootFile) of
{ok,Bin,_} ->
case binary_to_term(Bin) of
{script,Id,CmdList} when is_list(CmdList) ->
init ! {self(),{script_id,Id}}, % ;-)
{ok, CmdList};
_ ->
error
end;
_ ->
not_found
end.
%%
%% Eval a boot script.
%% Load modules and start processes.
%% If a start command does not spawn a new process the
%% boot process hangs (we want to ensure syncronicity).
%%
eval_script([{progress,Info}|CfgL],Init,PathFs,Vars,P,Ph,Deb,PathChoice) ->
debug(Deb,{progress,Info}),
init ! {self(),progress,Info},
eval_script(CfgL,Init,PathFs,Vars,P,Ph,Deb,PathChoice);
eval_script([{preLoaded,_}|CfgL],Init,PathFs,Vars,P,Ph,Deb,PathChoice) ->
eval_script(CfgL,Init,PathFs,Vars,P,Ph,Deb,PathChoice);
eval_script([{path,Path}|CfgL],Init,{Pa,Pz},Vars,false,Ph,Deb,PathChoice) ->
RealPath0 = make_path(Pa, Pz, Path, Vars),
RealPath = patch_path(RealPath0, PathChoice),
erl_prim_loader:set_path(RealPath),
eval_script(CfgL,Init,{Pa,Pz},Vars,false,Ph,Deb,PathChoice);
eval_script([{path,_}|CfgL],Init,PathFs,Vars,P,Ph,Deb,PathChoice) ->
%% Ignore, use the command line -path flag.
eval_script(CfgL,Init,PathFs,Vars,P,Ph,Deb,PathChoice);
eval_script([{kernel_load_completed}|CfgL],Init,PathFs,Vars,P,{_,embedded,Par},Deb,PathChoice) ->
eval_script(CfgL,Init,PathFs,Vars,P,{true,embedded,Par},Deb,PathChoice);
eval_script([{kernel_load_completed}|CfgL],Init,PathFs,Vars,P,{_,E,Par},Deb,PathChoice) ->
eval_script(CfgL,Init,PathFs,Vars,P,{false,E,Par},Deb,PathChoice);
eval_script([{primLoad,Mods}|CfgL],Init,PathFs,Vars,P,{true,E,Par},Deb,PathChoice)
when is_list(Mods) ->
if
Par =:= true ->
par_load_modules(Mods,Init);
true ->
load_modules(Mods)
end,
eval_script(CfgL,Init,PathFs,Vars,P,{true,E,Par},Deb,PathChoice);
eval_script([{primLoad,_Mods}|CfgL],Init,PathFs,Vars,P,{false,E,Par},Deb,PathChoice) ->
%% Do not load now, code_server does that dynamically!
eval_script(CfgL,Init,PathFs,Vars,P,{false,E,Par},Deb,PathChoice);
eval_script([{kernelProcess,Server,{Mod,Fun,Args}}|CfgL],Init,
PathFs,Vars,P,Ph,Deb,PathChoice) ->
debug(Deb,{start,Server}),
start_in_kernel(Server,Mod,Fun,Args,Init),
eval_script(CfgL,Init,PathFs,Vars,P,Ph,Deb,PathChoice);
eval_script([{apply,{Mod,Fun,Args}}|CfgL],Init,PathFs,Vars,P,Ph,Deb,PathChoice) ->
debug(Deb,{apply,{Mod,Fun,Args}}),
apply(Mod,Fun,Args),
eval_script(CfgL,Init,PathFs,Vars,P,Ph,Deb,PathChoice);
eval_script([],_,_,_,_,_,_,_) ->
ok;
eval_script(What,_,_,_,_,_,_,_) ->
exit({'unexpected command in bootfile',What}).
load_modules([Mod|Mods]) ->
File = concat([Mod,objfile_extension()]),
{ok,Full} = load_mod(Mod,File),
init ! {self(),loaded,{Mod,Full}}, %% Tell init about loaded module
load_modules(Mods);
load_modules([]) ->
ok.
%%% An optimization: erl_prim_loader gets the chance of loading many
%%% files in parallel, using threads. This will reduce the seek times,
%%% and loaded code can be processed while other threads are waiting
%%% for the disk. The optimization is not tried unless the loader is
%%% "efile" and there is a non-empty pool of threads.
%%%
%%% Many threads are needed to get a good result, so it would be
%%% beneficial to load several applications in parallel. However,
%%% measurements show that the file system handles one directory at a
%%% time, regardless if parallel threads are created for files on
%%% several directories (a guess: writing the meta information when
%%% the file was last read ('mtime'), forces the file system to sync
%%% between directories).
par_load_modules(Mods,Init) ->
Ext = objfile_extension(),
ModFiles = [{Mod,concat([Mod,Ext])} || Mod <- Mods,
not erlang:module_loaded(Mod)],
Self = self(),
Fun = fun(Mod, BinCode, FullName) ->
case catch load_mod_code(Mod, BinCode, FullName) of
{ok, _} ->
Init ! {Self,loaded,{Mod,FullName}},
ok;
_EXIT ->
{error, Mod}
end
end,
case erl_prim_loader:get_files(ModFiles, Fun) of
ok ->
ok;
{error,Mod} ->
exit({'cannot load',Mod,get_files})
end.
make_path(Pa, Pz, Path, Vars) ->
append([Pa,append([fix_path(Path,Vars),Pz])]).
%% For all Paths starting with $ROOT add rootdir and for those
%% starting with $xxx/, expand $xxx to the value supplied with -boot_var!
%% If $xxx cannot be expanded this process terminates.
fix_path([Path|Ps], Vars) when is_atom(Path) ->
[add_var(atom_to_list(Path), Vars)|fix_path(Ps, Vars)];
fix_path([Path|Ps], Vars) ->
[add_var(Path, Vars)|fix_path(Ps, Vars)];
fix_path(_, _) ->
[].
add_var("$ROOT/" ++ Path, {Root,_}) ->
concat([Root, "/", Path]);
add_var([$$|Path0], {_,VarList}) ->
{Var,Path} = extract_var(Path0,[]),
Value = b2s(get_var_value(list_to_binary(Var),VarList)),
concat([Value, "/", Path]);
add_var(Path, _) ->
Path.
extract_var([$/|Path],Var) -> {reverse(Var),Path};
extract_var([H|T],Var) -> extract_var(T,[H|Var]);
extract_var([],Var) -> {reverse(Var),[]}.
%% get_var_value(Var, [Vars]) where Vars == [atom()]
get_var_value(Var,[Vars|VarList]) ->
case get_var_val(Var,Vars) of
{ok, Value} ->
Value;
_ ->
get_var_value(Var,VarList)
end;
get_var_value(Var,[]) ->
exit(list_to_atom(concat(["cannot expand \$", Var, " in bootfile"]))).
get_var_val(Var,[Var,Value|_]) -> {ok, Value};
get_var_val(Var,[_,_|Vars]) -> get_var_val(Var,Vars);
get_var_val(_,_) -> false.
patch_path(Dirs, strict) ->
Dirs;
patch_path(Dirs, relaxed) ->
ArchiveExt = archive_extension(),
[patch_dir(Dir, ArchiveExt) || Dir <- Dirs].
patch_dir(Orig, ArchiveExt) ->
case funny_split(Orig, $/) of
["nibe", RevApp, RevArchive | RevTop] ->
App = reverse(RevApp),
case funny_splitwith(RevArchive, $.) of
{Ext, Base} when Ext =:= ArchiveExt, Base =:= App ->
%% Orig archive
Top = reverse([reverse(C) || C <- RevTop]),
Dir = join(Top ++ [App, "ebin"], "/"),
Archive = Orig;
_ ->
%% Orig directory
Top = reverse([reverse(C) || C <- [RevArchive | RevTop]]),
Archive = join(Top ++ [App ++ ArchiveExt, App, "ebin"], "/"),
Dir = Orig
end,
%% First try dir, second try archive and at last use orig if both fails
case erl_prim_loader:read_file_info(Dir) of
{ok, #file_info{type = directory}} ->
Dir;
_ ->
case erl_prim_loader:read_file_info(Archive) of
{ok, #file_info{type = directory}} ->
Archive;
_ ->
Orig
end
end;
_ ->
Orig
end.
%% 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].
%% Returns {BeforeSep, AfterSep} where BeforeSep is in reverse order
funny_splitwith(List, Sep) ->
funny_splitwith(List, Sep, [], List).
funny_splitwith([Sep | Tail], Sep, Acc, _Orig) ->
{Acc, Tail};
funny_splitwith([Head | Tail], Sep, Acc, Orig) ->
funny_splitwith(Tail, Sep, [Head | Acc], Orig);
funny_splitwith([], _Sep, _Acc, Orig) ->
{[], Orig}.
-spec join([string()], string()) -> string().
join([H1, H2 | T], S) ->
H1 ++ S ++ join([H2 | T], S);
join([H], _) ->
H.
%% Servers that are located in the init kernel are linked
%% and supervised by init.
start_in_kernel(Server,Mod,Fun,Args,Init) ->
Res = apply(Mod,Fun,Args),
Init ! {self(),started,{Server,Res}},
receive
{Init,ok,Pid} ->
unlink(Pid), %% Just for sure...
ok;
{Init,ignore} ->
ignore
end.
%% Do start all processes specified at command line using -s!
%% Use apply here instead of spawn to ensure syncronicity for
%% those servers that wish to have it so.
%% Disadvantage: anything started with -s that does not
%% eventually spawn will hang the startup routine.
%% We also handle -eval here. The argument is an arbitrary
%% expression that should be parsed and evaluated.
start_em([S|Tail]) ->
case whereis(user) of
undefined ->
ok;
P when is_pid(P) -> %Let's set the group_leader()
erlang:group_leader(P, self())
end,
start_it(S),
start_em(Tail);
start_em([]) -> ok.
start_it([]) ->
ok;
start_it({eval,Bin}) ->
Str = binary_to_list(Bin),
{ok,Ts,_} = erl_scan:string(Str),
Ts1 = case reverse(Ts) of
[{dot,_}|_] -> Ts;
TsR -> reverse([{dot,1} | TsR])
end,
{ok,Expr} = erl_parse:parse_exprs(Ts1),
erl_eval:exprs(Expr, []),
ok;
start_it([_|_]=MFA) ->
Ref = make_ref(),
case catch {Ref,case MFA of
[M] -> M:start();
[M,F] -> M:F();
[M,F|Args] -> M:F(Args) % Args is a list
end} of
{Ref,R} ->
R;
{'EXIT',Reason} ->
exit(Reason);
Other ->
throw(Other)
end.
%%
%% Fetch a module and load it into the system.
%%
load_mod(Mod, File) ->
case erlang:module_loaded(Mod) of
false ->
case erl_prim_loader:get_file(File) of
{ok,BinCode,FullName} ->
load_mod_code(Mod, BinCode, FullName);
_ ->
exit({'cannot load',Mod,get_file})
end;
_ -> % Already loaded.
{ok,File}
end.
load_mod_code(Mod, BinCode, FullName) ->
case erlang:module_loaded(Mod) of
false ->
case erlang:load_module(Mod, BinCode) of
{module,Mod} -> {ok,FullName};
{error,on_load} ->
?ON_LOAD_HANDLER ! {loaded,Mod},
{ok,FullName};
Other ->
exit({'cannot load',Mod,Other})
end;
_ -> % Already loaded.
{ok,FullName}
end.
%% --------------------------------------------------------
%% If -shutdown_time is specified at the command line
%% this timer will inform the init process that it has to
%% force processes to terminate. It cannot be handled
%% softly any longer.
%% --------------------------------------------------------
shutdown_timer(Flags) ->
case get_flag('-shutdown_time',Flags,infinity) of
infinity ->
self();
Time ->
case catch list_to_integer(binary_to_list(Time)) of
T when is_integer(T) ->
Pid = spawn(fun() -> timer(T) end),
receive
{Pid, started} ->
Pid
end;
_ ->
self()
end
end.
flush_timout(Pid) ->
receive
{Pid, timeout} -> true
after 0 -> true
end.
timer(T) ->
init ! {self(), started},
receive
after T ->
init ! {self(), timeout}
end.
%% --------------------------------------------------------
%% Parse the command line arguments and extract things to start, flags
%% and other arguments. We keep the relative of the groups.
%% --------------------------------------------------------
parse_boot_args(Args) ->
parse_boot_args(Args, [], [], []).
parse_boot_args([B|Bs], Ss, Fs, As) ->
case check(B) of
start_extra_arg ->
{reverse(Ss),reverse(Fs),lists:reverse(As, Bs)}; % BIF
start_arg ->
{S,Rest} = get_args(Bs, []),
parse_boot_args(Rest, [{s, S}|Ss], Fs, As);
start_arg2 ->
{S,Rest} = get_args(Bs, []),
parse_boot_args(Rest, [{run, S}|Ss], Fs, As);
eval_arg ->
{Expr,Rest} = get_args(Bs, []),
parse_boot_args(Rest, [{eval, Expr}|Ss], Fs, As);
flag ->
{F,Rest} = get_args(Bs, []),
Fl = case F of
[] -> [B];
FF -> [B,FF]
end,
parse_boot_args(Rest, Ss,
[list_to_tuple(Fl)|Fs], As);
arg ->
parse_boot_args(Bs, Ss, Fs, [B|As]);
end_args ->
parse_boot_args(Bs, Ss, Fs, As)
end;
parse_boot_args([], Start, Flags, Args) ->
{reverse(Start),reverse(Flags),reverse(Args)}.
check(<<"-extra">>) -> start_extra_arg;
check(<<"-s">>) -> start_arg;
check(<<"-run">>) -> start_arg2;
check(<<"-eval">>) -> eval_arg;
check(<<"--">>) -> end_args;
check(X) when is_binary(X) ->
case binary_to_list(X) of
[$-|_Rest] -> flag;
_Chars -> arg %Even empty atoms
end;
check(_X) -> arg. %This should never occur
get_args([B|Bs], As) ->
case check(B) of
start_extra_arg -> {reverse(As), [B|Bs]};
start_arg -> {reverse(As), [B|Bs]};
start_arg2 -> {reverse(As), [B|Bs]};
eval_arg -> {reverse(As), [B|Bs]};
end_args -> {reverse(As), Bs};
flag -> {reverse(As), [B|Bs]};
arg ->
get_args(Bs, [B|As])
end;
get_args([], As) -> {reverse(As),[]}.
%%
%% Internal get_flag function, with default value.
%% Return: true if flag given without args
%% atom() if a single arg was given.
%% list(atom()) if several args were given.
%%
get_flag(F,Flags,Default) ->
case catch get_flag(F,Flags) of
{'EXIT',_} ->
Default;
Value ->
Value
end.
get_flag(F,Flags) ->
case search(F,Flags) of
{value,{F,[V]}} ->
V;
{value,{F,V}} ->
V;
{value,{F}} -> % Flag given!
true;
_ ->
exit(list_to_atom(concat(["no ",F," flag"])))
end.
%%
%% Internal get_flag function, with default value.
%% Return: list(atom())
%%
get_flag_list(F,Flags,Default) ->
case catch get_flag_list(F,Flags) of
{'EXIT',_} ->
Default;
Value ->
Value
end.
get_flag_list(F,Flags) ->
case search(F,Flags) of
{value,{F,V}} ->
V;
_ ->
exit(list_to_atom(concat(["no ",F," flag"])))
end.
%%
%% Internal get_flag function.
%% Fetch all occurrences of flag.
%% Return: [Args,Args,...] where Args ::= list(atom())
%%
get_flag_args(F,Flags) -> get_flag_args(F,Flags,[]).
get_flag_args(F,[{F,V}|Flags],Acc) when is_list(V) ->
get_flag_args(F,Flags,[V|Acc]);
get_flag_args(F,[{F,V}|Flags],Acc) ->
get_flag_args(F,Flags,[[V]|Acc]);
get_flag_args(F,[_|Flags],Acc) ->
get_flag_args(F,Flags,Acc);
get_flag_args(_,[],Acc) ->
reverse(Acc).
get_arguments([{F,V}|Flags]) ->
[$-|Fl] = atom_to_list(F),
[{list_to_atom(Fl),to_strings(V)}|get_arguments(Flags)];
get_arguments([{F}|Flags]) ->
[$-|Fl] = atom_to_list(F),
[{list_to_atom(Fl),[]}|get_arguments(Flags)];
get_arguments([]) ->
[].
to_strings([H|T]) when is_atom(H) -> [atom_to_list(H)|to_strings(T)];
to_strings([H|T]) when is_binary(H) -> [binary_to_list(H)|to_strings(T)];
to_strings([]) -> [].
get_argument(Arg,Flags) ->
Args = get_arguments(Flags),
case get_argument1(Arg,Args) of
[] ->
error;
Value ->
{ok,Value}
end.
get_argument1(Arg,[{Arg,V}|Args]) ->
[V|get_argument1(Arg,Args)];
get_argument1(Arg,[_|Args]) ->
get_argument1(Arg,Args);
get_argument1(_,[]) ->
[].
set_argument([{Flag,_}|Flags],Flag,Value) ->
[{Flag,[Value]}|Flags];
set_argument([{Flag}|Flags],Flag,Value) ->
[{Flag,[Value]}|Flags];
set_argument([Item|Flags],Flag,Value) ->
[Item|set_argument(Flags,Flag,Value)];
set_argument([],Flag,Value) ->
[{Flag,[Value]}].
concat([A|T]) when is_atom(A) ->
atom_to_list(A) ++ concat(T);
concat([C|T]) when is_integer(C), 0 =< C, C =< 255 ->
[C|concat(T)];
concat([Bin|T]) when is_binary(Bin) ->
binary_to_list(Bin) ++ concat(T);
concat([S|T]) ->
S ++ concat(T);
concat([]) ->
[].
append(L, Z) -> L ++ Z.
append([E]) -> E;
append([H|T]) ->
H ++ append(T);
append([]) -> [].
reverse([] = L) ->
L;
reverse([_] = L) ->
L;
reverse([A, B]) ->
[B, A];
reverse([A, B | L]) ->
lists:reverse(L, [B, A]). % BIF
search(Key, [H|_T]) when is_tuple(H), element(1, H) =:= Key ->
{value, H};
search(Key, [_|T]) ->
search(Key, T);
search(_Key, []) ->
false.
-spec objfile_extension() -> nonempty_string().
objfile_extension() ->
".beam".
%% case erlang:system_info(machine) of
%% "JAM" -> ".jam";
%% "VEE" -> ".vee";
%% "BEAM" -> ".beam"
%% end.
-spec archive_extension() -> nonempty_string().
archive_extension() ->
".ez".
%%%
%%% Support for handling of on_load functions.
%%%
run_on_load_handlers() ->
Ref = monitor(process, ?ON_LOAD_HANDLER),
catch ?ON_LOAD_HANDLER ! run_on_load,
receive
{'DOWN',Ref,process,_,noproc} ->
%% There is no on_load handler process,
%% probably because init:restart/0 has been
%% called and it is not the first time we
%% pass through here.
ok;
{'DOWN',Ref,process,_,on_load_done} ->
ok;
{'DOWN',Ref,process,_,Res} ->
%% Failure to run an on_load handler.
%% This is fatal during start-up.
exit(Res)
end.
start_on_load_handler_process() ->
register(?ON_LOAD_HANDLER,
spawn(fun on_load_handler_init/0)).
on_load_handler_init() ->
on_load_loop([], false).
on_load_loop(Mods, Debug0) ->
receive
{init_debug_flag,Debug} ->
on_load_loop(Mods, Debug);
{loaded,Mod} ->
on_load_loop([Mod|Mods], Debug0);
run_on_load ->
run_on_load_handlers(Mods, Debug0),
exit(on_load_done)
end.
run_on_load_handlers([M|Ms], Debug) ->
debug(Debug, {running_on_load_handler,M}),
Fun = fun() ->
Res = erlang:call_on_load_function(M),
exit(Res)
end,
{Pid,Ref} = spawn_monitor(Fun),
receive
{'DOWN',Ref,process,Pid,OnLoadRes} ->
Keep = OnLoadRes =:= ok,
erlang:finish_after_on_load(M, Keep),
case Keep of
false ->
Error = {on_load_function_failed,M},
debug(Debug, Error),
exit(Error);
true ->
debug(Debug, {on_load_handler_returned_ok,M}),
run_on_load_handlers(Ms, Debug)
end
end;
run_on_load_handlers([], _) -> ok.
