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macula
14.5.0
15.0.0-rc.2
15.0.0-rc.1
14.10.0
14.9.0
14.8.2
14.8.1
14.8.0
14.7.0
14.6.0
14.5.0
14.4.0
14.3.0
14.2.1
14.2.0
14.1.0
14.0.0
13.6.0
13.5.0
13.4.0
13.3.0
13.2.2
13.2.1
13.2.0
13.1.0
13.0.1
13.0.0
12.12.0
12.11.1
12.11.0
12.10.0
12.9.1
12.9.0
12.8.0
12.7.0
12.6.0
12.5.1
12.5.0
12.4.0
12.3.0
12.2.1
12.2.0
12.1.0
12.0.0
11.5.0
11.4.0
11.3.1
11.3.0
11.2.0
11.1.0
11.0.0
10.25.0
10.24.0
10.23.0
10.22.0
10.21.0
10.20.3
10.20.2
10.20.0
10.19.2
10.19.1
10.19.0
10.18.0
10.17.0
10.16.0
10.15.0
10.14.5
10.14.4
10.14.2
10.14.1
10.14.0
10.13.2
10.13.1
10.11.0
10.10.2
10.10.1
10.10.0
10.9.1
10.9.0
10.8.0
10.7.0
10.5.8
10.5.7
10.5.6
10.5.5
10.5.4
10.5.3
10.5.2
10.5.1
10.5.0
10.4.0
10.2.0
10.1.1
10.1.0
10.0.2
10.0.1
10.0.0
9.13.8
9.8.2
9.8.1
9.8.0
9.5.0
9.4.0
9.3.1
9.3.0
9.2.0
9.1.1
9.1.0
9.0.0
8.7.0
8.6.0
8.5.0
8.4.1
8.4.0
8.3.0
8.2.0
8.1.0
8.0.2
8.0.1
8.0.0
7.1.0
7.0.0
6.0.0
5.2.2
5.2.1
5.2.0
5.1.0
5.0.0
4.8.0
4.7.1
4.7.0
4.6.0
4.5.0
4.4.10
4.4.9
4.4.8
4.4.7
4.4.6
4.4.5
4.4.4
4.4.3
4.4.2
4.4.1
4.4.0
4.3.1
4.3.0
4.2.9
4.2.8
4.2.7
4.2.6
4.2.5
4.2.4
4.2.3
4.2.2
4.2.1
4.2.0
4.1.1
4.1.0
4.0.0
3.16.0
3.15.3
3.15.2
3.15.1
3.14.0
3.13.0
3.12.1
3.12.0
3.11.1
3.11.0
3.10.3
3.10.2
3.10.1
3.9.0
3.8.0
3.7.0
3.5.0
3.4.0
3.3.0
3.2.0
3.1.0
3.0.0
2.1.1
2.1.0
2.0.0
1.5.2
1.5.1
1.4.30
1.4.29
1.4.28
1.4.27
1.4.26
1.4.25
1.4.24
1.4.23
1.4.22
1.4.21
1.4.20
1.4.19
1.4.18
1.4.17
1.4.16
1.4.15
1.4.14
1.4.13
1.4.11
1.4.10
1.4.9
1.4.8
1.4.7
1.4.6
1.4.5
1.4.4
1.4.3
1.4.2
1.4.1
1.4.0
1.3.1
1.3.0
1.2.0
1.1.0
1.0.10
1.0.9
1.0.8
1.0.7
1.0.6
1.0.5
1.0.4
1.0.3
1.0.2
1.0.1
1.0.0
0.48.6
0.48.5
0.48.4
0.48.3
0.48.2
0.48.1
0.48.0
0.47.1
0.47.0
0.46.3
0.46.1
0.46.0
0.45.3
0.45.2
0.45.1
0.45.0
0.44.2
0.44.1
0.44.0
0.43.3
0.43.2
0.43.1
0.43.0
0.42.9
0.42.8
0.42.7
0.42.6
0.42.5
0.42.4
0.42.3
0.42.2
0.42.1
0.42.0
0.41.1
0.41.0
0.40.1
0.40.0
0.39.9
0.39.8
0.39.7
0.39.6
0.39.5
0.39.4
0.39.3
0.39.2
0.39.1
0.39.0
0.38.8
0.38.7
0.38.6
0.38.5
0.38.4
0.38.3
0.38.2
0.38.1
0.38.0
0.37.7
0.37.6
0.37.5
0.37.4
0.37.3
0.37.2
0.37.1
0.37.0
0.36.6
0.36.5
0.36.4
0.36.3
0.36.2
0.36.1
0.36.0
0.35.4
0.35.3
0.35.2
0.35.1
0.35.0
0.34.1
0.34.0
0.33.1
0.33.0
0.32.5
0.32.4
0.32.3
0.32.2
0.32.1
0.32.0
0.31.9
0.31.8
0.31.7
0.31.6
0.31.5
0.31.4
0.31.3
0.31.2
0.31.1
0.31.0
0.30.10
0.30.9
0.30.8
0.30.7
0.30.6
0.30.5
0.30.4
0.30.3
0.30.2
0.30.1
0.30.0
0.29.0
0.28.3
0.28.2
0.28.1
0.28.0
0.27.1
0.27.0
0.26.1
0.26.0
0.25.6
0.25.5
0.25.4
0.25.3
0.25.2
0.25.1
0.25.0
0.24.6
0.24.5
0.24.4
0.24.3
0.24.2
0.24.1
0.24.0
0.23.3
0.23.2
0.23.1
0.23.0
0.22.12
0.22.11
0.22.10
0.22.9
0.22.8
0.22.7
0.22.6
0.22.5
0.22.4
0.22.3
0.22.2
0.22.1
0.22.0
0.21.7
0.21.6
0.21.5
0.21.4
0.21.2
0.21.1
0.21.0
0.20.25
0.20.24
0.20.23
0.20.22
0.20.21
0.20.20
0.20.19
0.20.18
0.20.17
0.20.16
0.20.15
0.20.14
0.20.13
0.20.12
0.20.11
0.20.10
0.20.9
0.20.8
0.20.7
0.20.6
0.20.5
0.20.3
0.20.2
0.20.1
0.20.0
0.19.2
0.19.1
0.19.0
0.18.1
0.18.0
0.17.4
0.17.3
0.17.2
0.17.1
0.17.0
0.16.6
0.16.5
0.16.4
0.16.3
0.16.2
0.16.1
0.16.0
0.15.1
0.15.0
0.14.3
0.14.2
0.14.1
0.14.0
0.12.6
0.12.5
0.12.3
0.11.3
0.10.2
0.10.1
0.10.0
0.9.2
0.9.1
0.9.0
0.8.25
0.8.24
0.8.23
0.8.22
0.8.21
0.8.20
0.8.19
0.8.18
0.8.17
0.8.16
0.8.15
0.8.14
0.8.13
0.8.12
0.8.11
0.8.10
0.8.9
0.8.8
0.8.7
0.8.6
0.8.5
0.8.4
0.8.3
0.8.2
0.8.1
0.8.0
0.7.30
0.7.29
0.7.28
0.7.27
0.7.26
0.7.25
0.7.24
0.7.23
0.7.22
0.7.21
0.7.20
0.7.19
0.7.18
0.7.17
0.7.16
0.7.15
0.7.14
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0.7.12
0.7.11
0.7.10
0.7.9
0.7.8
0.7.7
0.7.6
0.7.5
0.7.4
0.7.3
0.7.2
0.7.1
0.7.0
0.6.7
0.6.6
0.6.5
0.6.4
0.6.3
0.6.2
0.6.1
0.6.0
0.5.0
0.4.4
0.4.3
0.4.2
0.4.1
0.4.0
0.3.4
0.3.3
0.3.2
0.3.1
Macula HTTP/3 Mesh SDK — connect, subscribe, publish, call, advertise
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Files
src/macula_reason_name.erl
%%%-------------------------------------------------------------------
%%% @doc What a reason is called when it leaves this node, and how much
%%% of it the local log prints.
%%%
%%% A peer, a remote caller or a published fact is told a reason's name
%%% and none of its terms. The name is the atom at the reason's head,
%%% such as `killed', `shutdown', `timeout' or `badmatch', looking
%%% through `{error, Reason}' and at most three tuples deep. A reason
%%% with no such atom, or whose atom's name is longer than 64 bytes, has
%%% no name.
%%%
%%% An error a handler answers its caller with may carry the handler's
%%% own text: a binary, or a list whose first 257 elements, or all of them
%%% if fewer, are printable Unicode characters. Only those elements of a
%%% list are looked at, however long it is. The text crosses as at most
%%% 256 bytes of valid UTF-8, cut on a character boundary.
%%%
%%% The whole reason stays on this node, where `logged/2' prints it for
%%% the log to at most 4,096 characters however large it is.
%%% @end
%%%-------------------------------------------------------------------
-module(macula_reason_name).
-export([text/1, reply_text/1, logged/2]).
%% The longest name a reason goes by.
-define(NAME_BYTES, 64).
%% How many tuples deep a reason is looked into for its name.
-define(NAME_DEPTH, 3).
%% The most bytes of a handler's own text that cross to its caller.
-define(REPLY_TEXT_BYTES, 256).
%% What ends a text that was cut.
-define(CUT, <<"...">>).
%% The most characters the log prints of a reason and what came with it.
-define(LOGGED_CHARS, 4096).
%% @doc The reason's name, such as `<<"timeout">>', or `<<"crashed">>'
%% when it has none. This is what an end fact or an abort message says
%% about why something ended.
-spec text(term()) -> binary().
text(Reason) ->
name_or_crashed(name(Reason)).
%% @doc The text a caller is told for an error a handler answered with:
%% the handler's own text when the reason is a binary or a list whose
%% first 257 elements are printable Unicode characters, as at most 256
%% bytes of valid UTF-8; otherwise the reason's name; `error' when the
%% reason has neither.
-spec reply_text(term()) -> {ok, binary()} | error.
reply_text(Text) when is_binary(Text) ->
{ok, within_reply_bytes(Text)};
reply_text(Reason) when is_list(Reason) ->
charlist_text(list_start(Reason, ?REPLY_TEXT_BYTES + 1, []));
reply_text(Reason) ->
name(Reason).
%% @doc `Format' and `Args' printed for the local log, to at most 4,096
%% characters however large the terms in `Args' are. The print stops
%% early on large terms, and what it gives is cut to the bound.
-spec logged(io:format(), [term()]) -> unicode:chardata().
logged(Format, Args) ->
Print = io_lib:format(Format, Args, [{chars_limit, ?LOGGED_CHARS}]),
string:slice(Print, 0, ?LOGGED_CHARS).
name_or_crashed({ok, Name}) -> Name;
name_or_crashed(error) -> <<"crashed">>.
charlist_text({ok, Start}) ->
printable_text(io_lib:printable_unicode_list(Start), Start);
charlist_text(error) ->
error.
printable_text(true, Chars) ->
{ok, within_reply_bytes(unicode:characters_to_binary(Chars))};
printable_text(false, _List) ->
error.
%% A character takes at least one byte, so a list's first 257 elements
%% hold all of its text that can cross and show whether there was more.
%% A list that ends improperly among them is not text.
list_start([Elem | Rest], Left, Start) when Left > 0 ->
list_start(Rest, Left - 1, [Elem | Start]);
list_start([], _Left, Start) ->
{ok, lists:reverse(Start)};
list_start([_ | _], 0, Start) ->
{ok, lists:reverse(Start)};
list_start(_Improper, _Left, _Start) ->
error.
name(Reason) ->
name_text(head_atom(Reason, ?NAME_DEPTH)).
head_atom(Name, _Depth) when is_atom(Name) ->
{ok, Name};
head_atom({error, Reason}, Depth) when Depth > 0 ->
head_atom(Reason, Depth - 1);
head_atom(Reason, Depth) when is_tuple(Reason), tuple_size(Reason) > 0, Depth > 0 ->
head_atom(element(1, Reason), Depth - 1);
head_atom(_Reason, _Depth) ->
error.
name_text({ok, Name}) -> within_name_bytes(atom_to_binary(Name, utf8));
name_text(error) -> error.
within_name_bytes(Text) when byte_size(Text) =< ?NAME_BYTES -> {ok, Text};
within_name_bytes(_Text) -> error.
%% The text whole when it is valid UTF-8 and fits, otherwise its longest
%% valid start that fits with the cut mark after it.
within_reply_bytes(Text) ->
whole_or_cut(Text, valid_start(Text)).
whole_or_cut(Text, Text) when byte_size(Text) =< ?REPLY_TEXT_BYTES ->
Text;
whole_or_cut(Text, _ValidStart) ->
Room = ?REPLY_TEXT_BYTES - byte_size(?CUT),
Start = valid_start(binary:part(Text, 0, min(Room, byte_size(Text)))),
<<Start/binary, ?CUT/binary>>.
valid_start(Bytes) ->
valid(unicode:characters_to_binary(Bytes)).
valid(Valid) when is_binary(Valid) -> Valid;
valid({incomplete, Valid, _Rest}) -> Valid;
valid({error, Valid, _Rest}) -> Valid.