1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
|
%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
%%
%% 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
%%
%% 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%
%%
-module(error_handler).
%% FIXME: remove no_native directive after HiPE has been changed to make
%% remote calls link to the target's Export* like BEAM does.
%% For a detailed explanation see the commit titled
%% "error_handler: add no_native compiler directive"
-compile(no_native).
%% Callbacks called from the run-time system.
-export([undefined_function/3,undefined_lambda/3,breakpoint/3]).
%% Exported utility functions.
-export([raise_undef_exception/3]).
-export([stub_function/3]).
-spec undefined_function(Module, Function, Args) ->
any() when
Module :: atom(),
Function :: atom(),
Args :: list().
undefined_function(Module, Func, Args) ->
case ensure_loaded(Module) of
{module, Module} ->
case erlang:function_exported(Module, Func, length(Args)) of
true ->
apply(Module, Func, Args);
false ->
call_undefined_function_handler(Module, Func, Args)
end;
{module, _} ->
crash(Module, Func, Args);
_Other ->
crash(Module, Func, Args)
end.
-spec undefined_lambda(Module, Fun, Args) -> term() when
Module :: atom(),
Fun :: fun(),
Args :: list().
undefined_lambda(Module, Fun, Args) ->
case ensure_loaded(Module) of
{module, Module} ->
%% There is no need (and no way) to test if the fun is present.
%% apply/2 will not call us again if the fun is missing.
apply(Fun, Args);
{module, _} ->
crash(Fun, Args);
_Other ->
crash(Fun, Args)
end.
-spec breakpoint(Module :: atom(), Function :: atom(), Args :: [_]) ->
any().
breakpoint(Module, Func, Args) ->
(int()):eval(Module, Func, Args).
-spec raise_undef_exception(Module, Function, Args) -> no_return() when
Module :: atom(),
Function :: atom(),
Args :: list().
raise_undef_exception(Module, Func, Args) ->
crash({Module,Func,Args,[]}).
%% Used to make the call to the 'int' module a "weak" one, to avoid
%% building strong components in xref or dialyzer.
int() -> int.
%%
%% Crash providing a beautiful stack backtrace.
%%
-spec crash(atom(), [term()]) -> no_return().
crash(Fun, Args) ->
crash({Fun,Args,[]}).
-spec crash(atom(), atom(), arity() | [term()]) -> no_return().
crash(M, F, A) ->
crash({M,F,A,[]}).
-spec crash(tuple()) -> no_return().
crash(Tuple) ->
try erlang:error(undef)
catch
error:undef ->
Stk = [Tuple|tl(erlang:get_stacktrace())],
erlang:raise(error, undef, Stk)
end.
%% If the code_server has not been started yet dynamic code loading
%% is handled by init.
ensure_loaded(Module) ->
Self = self(),
case whereis(code_server) of
%% Perhaps double fault should be detected in code:ensure_loaded/1
%% instead, since this error handler cannot know whether the
%% code server can resolve the problem or not.
%% An {error, Reason} return from there would crash the code server and
%% bring down the node.
Self ->
Error = "The code server called the unloaded module `" ++
atom_to_list(Module) ++ "'",
halt(Error);
Pid when is_pid(Pid) ->
code:ensure_loaded(Module);
_ ->
init:ensure_loaded(Module)
end.
-spec stub_function(atom(), atom(), [_]) -> no_return().
stub_function(Mod, Func, Args) ->
exit({undef,[{Mod,Func,Args,[]}]}).
call_undefined_function_handler(Module, Func, Args) ->
Handler = '$handle_undefined_function',
case erlang:function_exported(Module, Handler, 2) of
false ->
crash(Module, Func, Args);
true ->
Module:Handler(Func, Args)
end.
|
