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
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
%% -*- tab-width: 4;erlang-indent-level: 4;indent-tabs-mode: nil -*-
%% ex: ts=4 sw=4 et
%% -------------------------------------------------------------------
%%
%% rebar: Erlang Build Tools
%%
%% Copyright (c) 2009 Dave Smith (dizzyd@dizzyd.com)
%%
%% Permission is hereby granted, free of charge, to any person obtaining a copy
%% of this software and associated documentation files (the "Software"), to deal
%% in the Software without restriction, including without limitation the rights
%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
%% copies of the Software, and to permit persons to whom the Software is
%% furnished to do so, subject to the following conditions:
%%
%% The above copyright notice and this permission notice shall be included in
%% all copies or substantial portions of the Software.
%%
%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
%% THE SOFTWARE.
%%
%% -------------------------------------------------------------------
%% -------------------------------------------------------------------
%% This module borrows heavily from http://github.com/etnt/exrefcheck project as
%% written by Torbjorn Tornkvist <tobbe@kreditor.se>, Daniel Luna and others.
%% -------------------------------------------------------------------
-module(rebar_xref).
-include("rebar.hrl").
-export([xref/2]).
%% ===================================================================
%% Public API
%% ===================================================================
xref(Config, _) ->
%% Spin up xref
xref:start(xref),
ok = xref:set_library_path(xref, code_path()),
xref:set_default(xref, [{warnings, rebar_config:get(Config, xref_warnings, false)},
{verbose, rebar_config:is_verbose()}]),
{ok, _} = xref:add_directory(xref, "ebin"),
%% Get list of xref checks we want to run
XrefChecks = rebar_config:get(Config, xref_checks, [exports_not_used,
undefined_function_calls]),
%% Look for exports that are unused by anything
case lists:member(exports_not_used, XrefChecks) of
true ->
check_exports_not_used(Config);
false ->
ok
end,
%% Look for calls to undefined functions
case lists:member(undefined_function_calls, XrefChecks) of
true ->
check_undefined_function_calls(Config);
false ->
ok
end,
ok.
foobar() ->
ok.
%% ===================================================================
%% Internal functions
%% ===================================================================
check_exports_not_used(_Config) ->
{ok, UnusedExports0} = xref:analyze(xref, exports_not_used),
UnusedExports = filter_away_ignored(UnusedExports0),
%% Report all the unused functions
display_mfas(UnusedExports, "is unused export (Xref)"),
ok.
check_undefined_function_calls(_Config) ->
{ok, UndefinedCalls0} = xref:analyze(xref, undefined_function_calls),
UndefinedCalls = [{find_mfa_source(Caller), format_fa(Caller), format_mfa(Target)} ||
{Caller, Target} <- UndefinedCalls0],
[?CONSOLE("~s:~w: Warning ~s calls undefined function ~s\n",
[Source, Line, FunStr, Target]) ||
{{Source, Line}, FunStr, Target} <- UndefinedCalls],
ok.
code_path() ->
[P || P <- code:get_path(),
filelib:is_dir(P)].
%%
%% Ignore behaviour functions, and explicitly marked functions
%%
filter_away_ignored(UnusedExports) ->
%% Functions can be ignored by using
%% -ignore_xref([{F, A}, ...]).
%% Setup a filter function that build a list of behaviour callbacks and/or
%% any functions marked to ignore. We then use this list to mask any functions
%% marked as unused exports by xref
F = fun(Mod) ->
Attrs = ks(attributes, Mod:module_info()),
Ignore = ks(ignore_xref, Attrs),
Callbacks = [B:behaviour_info(callbacks) || B <- ks(behaviour, Attrs)],
[{Mod, F, A} || {F, A} <- Ignore ++ lists:flatten(Callbacks)]
end,
AttrIgnore = lists:flatten(lists:map(F, lists:usort([M || {M, _, _} <- UnusedExports]))),
[X || X <- UnusedExports, not(lists:member(X, AttrIgnore))].
ks(Key, List) ->
case lists:keysearch(Key, 1, List) of
{value, {Key, Value}} ->
Value;
false ->
[]
end.
display_mfas([], _Message) ->
ok;
display_mfas([{Mod, Fun, Args} = MFA | Rest], Message) ->
{Source, Line} = find_mfa_source(MFA),
?CONSOLE("~s:~w: Warning: function ~s/~w ~s\n", [Source, Line, Fun, Args, Message]),
display_mfas(Rest, Message).
format_mfa({M, F, A}) ->
?FMT("~s:~s/~w", [M, F, A]).
format_fa({_M, F, A}) ->
?FMT("~s/~w", [F, A]).
%%
%% Extract an element from a tuple, or undefined if N > tuple size
safe_element(N, Tuple) ->
case catch(element(N, Tuple)) of
{'EXIT', {badarg, _}} ->
undefined;
Value ->
Value
end.
%%
%% Extract the line number for a given function def
%%
abstract_code_function_line(Code, Name, Args) ->
[{function, Line, Name, _, _}] = [E || E <- Code,
safe_element(1, E) == function,
safe_element(3, E) == Name,
safe_element(4, E) == Args],
Line.
%%
%% Extract the original source filename from the abstract code
%%
abstract_code_source_file(Code) ->
[{attribute, 1, file, {Name, _}} | _] = Code,
Name.
%%
%% Given a MFA, find the file and LOC where it's defined. Note that
%% xref doesn't work if there is no abstract_code, so we can avoid
%% being too paranoid here.
%%
find_mfa_source({M, F, A}) ->
{M, Bin, _} = code:get_object_code(M),
{ok, {M, [{abstract_code, AbstractCode}]}} = beam_lib:chunks(Bin, [abstract_code]),
{raw_abstract_v1, Code} = AbstractCode,
Source = abstract_code_source_file(Code),
Line = abstract_code_function_line(Code, F, A),
{Source, Line}.
|
