diameter_spec_util -> diameter_dict_util and adapt to parser

Errors are now detected after the parse with format_error/1
providing understandable error messages, pointing to the
offending line number(s) in the dictionary source.

1 files changed, 0 insertions, 1089 deletions

diff --git a/lib/diameter/src/compiler/diameter_spec_util.erl b/lib/diameter/src/compiler/diameter_spec_util.erl
deleted file mode 100644
index 62536bf06d..0000000000
--- a/lib/diameter/src/compiler/diameter_spec_util.erl
+++ /dev/null
@@ -1,1089 +0,0 @@
-%%
-%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 2010-2011. 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%
-%%
-
-%%
-%% This module turns a .dia (aka spec) file into the orddict that
-%% diameter_codegen.erl in turn morphs into .erl and .hrl files for
-%% encode and decode of Diameter messages and AVPs.
-%%
-
--module(diameter_spec_util).
-
--export([parse/2]).
-
--define(ERROR(T), erlang:error({T, ?MODULE, ?LINE})).
--define(ATOM, list_to_atom).
-
-%% parse/1
-%%
-%% Output: orddict()
-
-parse(Path, Opts) ->
-    put({?MODULE, verbose}, lists:member(verbose, Opts)),
-    {ok, B} = file:read_file(Path),
-    Chunks = chunk(B),
-    Spec = reset(make_spec(Chunks), Opts, [name, prefix, inherits]),
-    true = groups_defined(Spec),  %% sanity checks
-    true = customs_defined(Spec), %%
-    Full = import_enums(import_groups(import_avps(insert_codes(Spec), Opts))),
-    true = enums_defined(Full),   %% sanity checks
-    true = v_flags_set(Spec),
-    Full.
-
-reset(Spec, Opts, Keys) ->
-    lists:foldl(fun(K,S) ->
-                        reset([{A,?ATOM(V)} || {A,V} <- Opts, A == K], S)
-                end,
-                Spec,
-                Keys).
-
-reset(L, Spec)
-  when is_list(L) ->
-    lists:foldl(fun reset/2, Spec, L);
-
-reset({inherits = Key, '-'}, Spec) ->
-    orddict:erase(Key, Spec);
-reset({inherits = Key, Dict}, Spec) ->
-    orddict:append(Key, Dict, Spec);
-reset({Key, Atom}, Spec) ->
-    orddict:store(Key, Atom, Spec);
-reset(_, Spec) ->
-    Spec.
-    
-%% Optional reports when running verbosely.
-report(What, Data) ->
-    report(get({?MODULE, verbose}), What, Data).
-
-report(true, Tag, Data) ->
-    io:format("##~n## ~p ~p~n", [Tag, Data]);
-report(false, _, _) ->
-    ok.
-
-%% chunk/1
-
-chunk(B) ->
-    chunkify(normalize(binary_to_list(B))).
-
-%% normalize/1
-%%
-%% Replace CR NL by NL, multiple NL by one, tab by space, and strip
-%% comments and leading/trailing space from each line. Precludes
-%% semicolons being used for any other purpose than comments.
-
-normalize(Str) ->
-    nh(Str, []).
-
-nh([], Acc) ->
-    lists:reverse(Acc);
-
-%% Trim leading whitespace.
-nh(Str, Acc) ->
-    nb(trim(Str), Acc).
-
-%% tab -> space
-nb([$\t|Rest], Acc) ->
-    nb(Rest, [$\s|Acc]);
-
-%% CR NL -> NL
-nb([$\r,$\n|Rest], Acc) ->
-    nt(Rest, Acc);
-
-%% Gobble multiple newlines before starting over again.
-nb([$\n|Rest], Acc) ->
-    nt(Rest, Acc);
-
-%% Comment.
-nb([$;|Rest], Acc) ->
-    nb(lists:dropwhile(fun(C) -> C /= $\n end, Rest), Acc);
-
-%% Just an ordinary character. Boring ...
-nb([C|Rest], Acc) ->
-    nb(Rest, [C|Acc]);
-
-nb([] = Str, Acc) ->
-    nt(Str, Acc).
-
-%% Discard a subsequent newline.
-nt(T, [$\n|_] = Acc) ->
-    nh(T, trim(Acc));
-
-%% Trim whitespace from the end of the line before continuing.
-nt(T, Acc) ->
-    nh(T, [$\n|trim(Acc)]).
-
-trim(S) ->
-    lists:dropwhile(fun(C) -> lists:member(C, "\s\t") end, S).
-
-%% chunkify/1
-%%
-%% Split the spec file into pieces delimited by lines starting with
-%% @Tag. Returns a list of {Tag, Args, Chunk} where Chunk is the
-%% string extending to the next delimiter. Note that leading
-%% whitespace has already been stripped.
-
-chunkify(Str) ->
-    %% Drop characters to the start of the first chunk.
-    {_, Rest} = split_chunk([$\n|Str]),
-    chunkify(Rest, []).
-
-chunkify([], Acc) ->
-    lists:reverse(Acc);
-
-chunkify(Rest, Acc) ->
-    {H,T} = split_chunk(Rest),
-    chunkify(T, [split_tag(H) | Acc]).
-
-split_chunk(Str) ->
-    split_chunk(Str, []).
-
-split_chunk([] = Rest, Acc) ->
-    {lists:reverse(Acc), Rest};
-split_chunk([$@|Rest], [$\n|_] = Acc) ->
-    {lists:reverse(Acc), Rest};
-split_chunk([C|Rest], Acc) ->
-    split_chunk(Rest, [C|Acc]).
-
-%% Expect a tag and its arguments on a single line.
-split_tag(Str) ->
-    {L, Rest} = get_until($\n, Str),
-    [{tag, Tag} | Toks] = diameter_spec_scan:parse(L),
-    {Tag, Toks, trim(Rest)}.
-
-get_until(EndT, L) ->
-    {H, [EndT | T]} = lists:splitwith(fun(C) -> C =/= EndT end, L),
-    {H,T}.
-
-%% ------------------------------------------------------------------------
-%% make_spec/1
-%%
-%% Turn chunks into spec.
-
-make_spec(Chunks) ->
-    lists:foldl(fun(T,A) -> report(chunk, T), chunk(T,A) end,
-                orddict:new(),
-                Chunks).
-
-chunk({T, [X], []}, Dict)
-  when T == name;
-       T == prefix ->
-    store(T, atomize(X), Dict);
-
-chunk({id = T, [{number, I}], []}, Dict) ->
-    store(T, I, Dict);
-
-chunk({vendor = T, [{number, I}, N], []}, Dict) ->
-    store(T, {I, atomize(N)}, Dict);
-
-%% inherits -> [{Mod, [AvpName, ...]}, ...]
-chunk({inherits = T, [_,_|_] = Args, []}, Acc) ->
-    Mods = [atomize(A) || A <- Args],
-    append_list(T, [{M,[]} || M <- Mods], Acc);
-chunk({inherits = T, [Mod], Body}, Acc) ->
-    append(T, {atomize(Mod), parse_avp_names(Body)}, Acc);
-
-%% avp_types -> [{AvpName, Code, Type, Flags, Encr}, ...]
-chunk({avp_types = T, [], Body}, Acc) ->
-    store(T, parse_avp_types(Body), Acc);
-
-%% custom_types -> [{Mod, [AvpName, ...]}, ...]
-chunk({custom_types = T, [Mod], Body}, Dict) ->
-    [_|_] = Avps = parse_avp_names(Body),
-    append(T, {atomize(Mod), Avps}, Dict);
-
-%% messages -> [{MsgName, Code, Type, Appl, Avps}, ...]
-chunk({messages = T, [], Body}, Acc) ->
-    store(T, parse_messages(Body), Acc);
-
-%% grouped -> [{AvpName, Code, Vendor, Avps}, ...]
-chunk({grouped = T, [], Body}, Acc) ->
-    store(T, parse_groups(Body), Acc);
-
-%% avp_vendor_id -> [{Id, [AvpName, ...]}, ...]
-chunk({avp_vendor_id = T, [{number, I}], Body}, Dict) ->
-    [_|_] = Names = parse_avp_names(Body),
-    append(T, {I, Names}, Dict);
-
-%% enums -> [{AvpName, [{Value, Name}, ...]}, ...]
-chunk({enum, [N], Str}, Dict) ->
-    append(enums, {atomize(N), parse_enums(Str)}, Dict);
-
-%% defines -> [{DefineName, [{Value, Name}, ...]}, ...]
-chunk({define, [N], Str}, Dict) ->
-    append(defines, {atomize(N), parse_enums(Str)}, Dict);
-chunk({result_code, [_] = N, Str}, Dict) ->  %% backwards compatibility
-    chunk({define, N, Str}, Dict);
-
-%% commands -> [{Name, Abbrev}, ...]
-chunk({commands = T, [], Body}, Dict) ->
-    store(T, parse_commands(Body), Dict);
-
-chunk(T, _) ->
-    ?ERROR({unknown_tag, T}).
-
-store(Key, Value, Dict) ->
-    error == orddict:find(Key, Dict) orelse ?ERROR({duplicate, Key}),
-    orddict:store(Key, Value, Dict).
-append(Key, Value, Dict) ->
-    orddict:append(Key, Value, Dict).
-append_list(Key, Values, Dict) ->
-    orddict:append_list(Key, Values, Dict).
-
-atomize({tag, T}) ->
-    T;
-atomize({name, T}) ->
-    ?ATOM(T).
-
-get_value(Keys, Spec)
-  when is_list(Keys) ->
-    [get_value(K, Spec) || K <- Keys];
-get_value(Key, Spec) ->
-    proplists:get_value(Key, Spec, []).
-
-%% ------------------------------------------------------------------------
-%% enums_defined/1
-%% groups_defined/1
-%% customs_defined/1
-%%
-%% Ensure that every local enum/grouped/custom is defined as an avp
-%% with an appropriate type.
-
-enums_defined(Spec) ->
-    Avps = get_value(avp_types, Spec),
-    Import = get_value(import_enums, Spec),
-    lists:all(fun({N,_}) ->
-                      true = enum_defined(N, Avps, Import)
-              end,
-              get_value(enums, Spec)).
-
-enum_defined(Name, Avps, Import) ->
-    case lists:keyfind(Name, 1, Avps) of
-        {Name, _, 'Enumerated', _, _} ->
-            true;
-        {Name, _, T, _, _} ->
-            ?ERROR({avp_has_wrong_type, Name, 'Enumerated', T});
-        false ->
-            lists:any(fun({_,Is}) -> lists:keymember(Name, 1, Is) end, Import)
-                orelse ?ERROR({avp_not_defined, Name, 'Enumerated'})
-    end.
-%% Note that an AVP is imported only if referenced by a message or
-%% grouped AVP, so the final branch will fail if an enum definition is
-%% extended without this being the case.
-
-groups_defined(Spec) ->
-    Avps = get_value(avp_types, Spec),
-    lists:all(fun({N,_,_,_}) -> true = group_defined(N, Avps) end,
-              get_value(grouped, Spec)).
-
-group_defined(Name, Avps) ->
-    case lists:keyfind(Name, 1, Avps) of
-        {Name, _, 'Grouped', _, _} ->
-            true;
-        {Name, _, T, _, _} ->
-            ?ERROR({avp_has_wrong_type, Name, 'Grouped', T});
-        false ->
-            ?ERROR({avp_not_defined, Name, 'Grouped'})
-    end.
-
-customs_defined(Spec) ->
-    Avps = get_value(avp_types, Spec),
-    lists:all(fun(A) -> true = custom_defined(A, Avps) end,
-              lists:flatmap(fun last/1, get_value(custom_types, Spec))).
-
-custom_defined(Name, Avps) ->
-    case lists:keyfind(Name, 1, Avps) of
-        {Name, _, T, _, _} when T == 'Grouped';
-                                T == 'Enumerated' ->
-            ?ERROR({avp_has_invalid_custom_type, Name, T});
-        {Name, _, _, _, _} ->
-            true;
-        false ->
-            ?ERROR({avp_not_defined, Name})
-    end.
-
-last({_,Xs}) -> Xs.
-
-%% ------------------------------------------------------------------------
-%% v_flags_set/1
-
-v_flags_set(Spec) ->
-    Avps = get_value(avp_types, Spec)
-        ++ lists:flatmap(fun last/1, get_value(import_avps, Spec)),
-    Vs = lists:flatmap(fun last/1, get_value(avp_vendor_id, Spec)),
-
-    lists:all(fun(N) -> vset(N, Avps) end, Vs).
-
-vset(Name, Avps) ->
-    A = lists:keyfind(Name, 1, Avps),
-    false == A andalso ?ERROR({avp_not_defined, Name}),
-    {Name, _Code, _Type, Flags, _Encr} = A,
-    lists:member('V', Flags) orelse ?ERROR({v_flag_not_set, A}).
-
-%% ------------------------------------------------------------------------
-%% insert_codes/1
-
-insert_codes(Spec) ->
-    [Msgs, Cmds] = get_value([messages, commands], Spec),
-
-    %% Code -> [{Name, Flags}, ...]
-    Dict = lists:foldl(fun({N,C,Fs,_,_}, D) -> dict:append(C,{N,Fs},D) end,
-                       dict:new(),
-                       Msgs),
-
-    %% list() of {Code, {ReqName, ReqAbbr}, {AnsName, AnsAbbr}}
-    %% If the name and abbreviation are the same then the 2-tuples
-    %% are replaced by the common atom()-valued name.
-    Codes = dict:fold(fun(C,Ns,A) -> [make_code(C, Ns, Cmds) | A] end,
-                      [],
-                      dict:erase(-1, Dict)),  %% answer-message
-
-    orddict:store(command_codes, Codes, Spec).
-
-make_code(Code, [_,_] = Ns, Cmds) ->
-    {Req, Ans} = make_names(Ns, lists:map(fun({_,Fs}) ->
-                                                  lists:member('REQ', Fs)
-                                          end,
-                                          Ns)),
-    {Code, abbrev(Req, Cmds), abbrev(Ans, Cmds)};
-
-make_code(Code, Cs, _) ->
-    ?ERROR({missing_request_or_answer, Code, Cs}).
-
-%% 3.3.  Diameter Command Naming Conventions
-%%
-%%    Diameter command names typically includes one or more English words
-%%    followed by the verb Request or Answer.  Each English word is
-%%    delimited by a hyphen.  A three-letter acronym for both the request
-%%    and answer is also normally provided.
-
-make_names([{Rname,_},{Aname,_}], [true, false]) ->
-    {Rname, Aname};
-make_names([{Aname,_},{Rname,_}], [false, true]) ->
-    {Rname, Aname};
-make_names([_,_] = Names, _) ->
-    ?ERROR({inconsistent_command_flags, Names}).
-
-abbrev(Name, Cmds) ->
-    case abbr(Name, get_value(Name, Cmds)) of
-        Name ->
-            Name;
-        Abbr ->
-            {Name, Abbr}
-    end.
-
-%% No explicit abbreviation: construct.
-abbr(Name, []) ->
-    ?ATOM(abbr(string:tokens(atom_to_list(Name), "-")));
-
-%% Abbreviation was specified.
-abbr(_Name, Abbr) ->
-    Abbr.
-
-%% No hyphens: already abbreviated.
-abbr([Abbr]) ->
-    Abbr;
-
-%% XX-Request/Answer ==> XXR/XXA
-abbr([[_,_] = P, T])
-  when T == "Request";
-       T == "Answer" ->
-    P ++ [hd(T)];
-
-%% XXX-...-YYY-Request/Answer ==> X...YR/X...YA
-abbr([_,_|_] = L) ->
-    lists:map(fun erlang:hd/1, L).
-
-%% ------------------------------------------------------------------------
-%% import_avps/2
-
-import_avps(Spec, Options) ->
-    Msgs = get_value(messages, Spec),
-    Groups = get_value(grouped, Spec),
-
-    %% Messages and groups require AVP's referenced by them.
-    NeededAvps
-        = ordsets:from_list(lists:flatmap(fun({_,_,_,_,As}) ->
-                                                  [avp_name(A) || A <- As]
-                                          end,
-                                          Msgs)
-                            ++ lists:flatmap(fun({_,_,_,As}) ->
-                                                     [avp_name(A) || A <- As]
-                                             end,
-                                             Groups)),
-    MissingAvps = missing_avps(NeededAvps, Spec),
-
-    report(needed, NeededAvps),
-    report(missing, MissingAvps),
-
-    Import = inherit(get_value(inherits, Spec), Options),
-
-    report(imported, Import),
-
-    ImportedAvps = lists:map(fun({N,_,_,_,_}) -> N end,
-                             lists:flatmap(fun last/1, Import)),
-
-    Unknown = MissingAvps -- ImportedAvps,
-
-    [] == Unknown orelse ?ERROR({undefined_avps, Unknown}),
-
-    orddict:store(import_avps, Import, orddict:erase(inherits, Spec)).
-
-%% missing_avps/2
-%%
-%% Given a list of AVP names and parsed spec, return the list of
-%% AVP's that aren't defined in this spec.
-
-missing_avps(NeededNames, Spec) ->
-    Avps = get_value(avp_types, Spec),
-    Groups = lists:map(fun({N,_,_,As}) ->
-                               {N, [avp_name(A) || A <- As]}
-                       end,
-                       get_value(grouped, Spec)),
-    Names = ordsets:from_list(['AVP' | lists:map(fun({N,_,_,_,_}) -> N end,
-                                                 Avps)]),
-    missing_avps(NeededNames, [], {Names, Groups}).
-
-avp_name({'<',A,'>'}) -> A;
-avp_name({A}) -> A;
-avp_name([A]) -> A;
-avp_name({_, A}) -> avp_name(A).
-
-missing_avps(NeededNames, MissingNames, {Names, _} = T) ->
-    missing(ordsets:filter(fun(N) -> lists:member(N, NeededNames) end, Names),
-            ordsets:union(NeededNames, MissingNames),
-            T).
-
-%% Nothing found locally.
-missing([], MissingNames, _) ->
-    MissingNames;
-
-%% Or not. Keep looking for for the AVP's needed by the found AVP's of
-%% type Grouped.
-missing(FoundNames, MissingNames, {_, Groups} = T) ->
-    NeededNames = lists:flatmap(fun({N,As}) ->
-                                  choose(lists:member(N, FoundNames), As, [])
-                          end,
-                          Groups),
-    missing_avps(ordsets:from_list(NeededNames),
-                 ordsets:subtract(MissingNames, FoundNames),
-                 T).
-
-%% inherit/2
-
-inherit(Inherits, Options) ->
-    Dirs = [D || {include, D} <- Options] ++ ["."],
-    lists:foldl(fun(T,A) -> find_avps(T, A, Dirs) end, [], Inherits).
-
-find_avps({Mod, AvpNames}, Acc, Path) ->
-    report(inherit_from, Mod),
-    Avps = avps_from_beam(find_beam(Mod, Path), Mod),  %% could be empty
-    [{Mod, lists:sort(find_avps(AvpNames, Avps))} | Acc].
-
-find_avps([], Avps) ->
-    Avps;
-find_avps(Names, Avps) ->
-    lists:filter(fun({N,_,_,_,_}) -> lists:member(N, Names) end, Avps).
-
-%% find_beam/2
-
-find_beam(Mod, Dirs)
-  when is_atom(Mod) ->
-    find_beam(atom_to_list(Mod), Dirs);
-find_beam(Mod, Dirs) ->
-    Beam = Mod ++ code:objfile_extension(),
-    case try_path(Dirs, Beam) of
-        {value, Path} ->
-            Path;
-        false ->
-            ?ERROR({beam_not_on_path, Beam, Dirs})
-    end.
-
-try_path([D|Ds], Fname) ->
-    Path = filename:join(D, Fname),
-    case file:read_file_info(Path) of
-        {ok, _} ->
-            {value, Path};
-        _ ->
-            try_path(Ds, Fname)
-    end;
-try_path([], _) ->
-    false.
-
-%% avps_from_beam/2
-
-avps_from_beam(Path, Mod) ->
-    report(beam, Path),
-    ok = load_module(code:is_loaded(Mod), Mod, Path),
-    orddict:fetch(avp_types, Mod:dict()).
-
-load_module(false, Mod, Path) ->
-    R = filename:rootname(Path, code:objfile_extension()),
-    {module, Mod} = code:load_abs(R),
-    ok;
-load_module({file, _}, _, _) ->
-    ok.
-
-choose(true, X, _)  -> X;
-choose(false, _, X) -> X.
-
-%% ------------------------------------------------------------------------
-%% import_groups/1
-%% import_enums/1
-%%
-%% For each inherited module, store the content of imported AVP's of
-%% type grouped/enumerated in a new key.
-
-import_groups(Spec) ->
-    orddict:store(import_groups, import(grouped, Spec), Spec).
-
-import_enums(Spec) ->
-    orddict:store(import_enums, import(enums, Spec), Spec).
-
-import(Key, Spec) ->
-    lists:flatmap(fun(T) -> import_key(Key, T) end,
-                  get_value(import_avps, Spec)).
-
-import_key(Key, {Mod, Avps}) ->
-    Imports = lists:flatmap(fun(T) ->
-                                    choose(lists:keymember(element(1,T),
-                                                           1,
-                                                           Avps),
-                                           [T],
-                                           [])
-                            end,
-                            get_value(Key, Mod:dict())),
-    if Imports == [] ->
-            [];
-       true ->
-            [{Mod, Imports}]
-    end.
-
-%% ------------------------------------------------------------------------
-%% parse_enums/1
-%%
-%% Enums are specified either as the integer value followed by the
-%% name or vice-versa. In the former case the name of the enum is
-%% taken to be the string up to the end of line, which may contain
-%% whitespace. In the latter case the integer may be parenthesized,
-%% specified in hex and followed by an inline comment. This is
-%% historical and will likely be changed to require a precise input
-%% format.
-%%
-%% Output: list() of {integer(), atom()}
-
-parse_enums(Str) ->
-    lists:flatmap(fun(L) -> parse_enum(trim(L)) end, string:tokens(Str, "\n")).
-
-parse_enum([]) ->
-    [];
-
-parse_enum(Str) ->
-    REs = [{"^(0[xX][0-9A-Fa-f]+|[0-9]+)\s+(.*?)\s*$", 1, 2},
-           {"^(.+?)\s+(0[xX][0-9A-Fa-f]+|[0-9]+)(\s+.*)?$", 2, 1},
-           {"^(.+?)\s+\\((0[xX][0-9A-Fa-f]+|[0-9]+)\\)(\s+.*)?$", 2, 1}],
-    parse_enum(Str, REs).
-
-parse_enum(Str, REs) ->
-    try lists:foreach(fun(R) -> enum(Str, R) end, REs) of
-        ok ->
-            ?ERROR({bad_enum, Str})
-    catch
-        throw: {enum, T} ->
-            [T]
-    end.
-
-enum(Str, {Re, I, N}) ->
-    case re:run(Str, Re, [{capture, all_but_first, list}]) of
-        {match, Vs} ->
-            T = list_to_tuple(Vs),
-            throw({enum, {to_int(element(I,T)), ?ATOM(element(N,T))}});
-        nomatch ->
-            ok
-    end.
-
-to_int([$0,X|Hex])
-  when X == $x;
-       X == $X ->
-    {ok, [I], _} = io_lib:fread("~#", "16#" ++ Hex),
-    I;
-to_int(I) ->
-    list_to_integer(I).
-
-%% ------------------------------------------------------------------------
-%% parse_messages/1
-%%
-%% Parse according to the ABNF for message specifications in 3.2 of
-%% RFC 3588 (shown below). We require all message and AVP names to
-%% start with a digit or uppercase character, except for the base
-%% answer-message, which is treated as a special case. Allowing names
-%% that start with a digit is more than the RFC specifies but the name
-%% doesn't affect what's sent over the wire. (Certains 3GPP standards
-%% use names starting with a digit. eg 3GPP-Charging-Id in TS32.299.)
-
-%%
-%% Sadly, not even the RFC follows this grammar. In particular, except
-%% in the example in 3.2, it wraps each command-name in angle brackets
-%% ('<' '>') which makes parsing a sequence of specifications require
-%% lookahead: after 'optional' avps have been parsed, it's not clear
-%% whether a '<' is a 'fixed' or whether it's the start of a
-%% subsequent message until we see whether or not '::=' follows the
-%% closing '>'. Require the grammar as specified.
-%%
-%% Output: list of {Name, Code, Flags, ApplId, Avps}
-%%
-%%         Name   = atom()
-%%         Code   = integer()
-%%         Flags  = integer()
-%%         ApplId = [] | [integer()]
-%%         Avps   = see parse_avps/1
-
-parse_messages(Str) ->
-    p_cmd(trim(Str), []).
-
-%%   command-def      = command-name "::=" diameter-message
-%%
-%%   command-name     = diameter-name
-%%
-%%   diameter-name    = ALPHA *(ALPHA / DIGIT / "-")
-%%
-%%   diameter-message = header  [ *fixed] [ *required] [ *optional]
-%%                      [ *fixed]
-%%
-%%   header           = "<" Diameter-Header:" command-id
-%%                      [r-bit] [p-bit] [e-bit] [application-id]">"
-%%
-%% The header spec (and example that follows it) is slightly mangled
-%% and, given the examples in the RFC should as follows:
-%%
-%%   header           = "<" "Diameter Header:" command-id
-%%                      [r-bit] [p-bit] [e-bit] [application-id]">"
-%%
-%% This is what's required/parsed below, modulo whitespace. This is
-%% also what's specified in the current draft standard at
-%% http://ftp.ietf.org/drafts/wg/dime.
-%%
-%% Note that the grammar specifies the order fixed, required,
-%% optional. In practise there seems to be little difference between
-%% the latter two since qualifiers can be used to change the
-%% semantics. For example 1*[XXX] and *1{YYY} specify 1 or more of the
-%% optional avp XXX and 0 or 1 of the required avp YYY, making the
-%% iotional avp required and the required avp optional. The current
-%% draft addresses this somewhat by requiring that min for a qualifier
-%% on an optional avp must be 0 if present. It doesn't say anything
-%% about required avps however, so specifying a min of 0 would still
-%% be possible. The draft also does away with the trailing *fixed.
-%%
-%% What will be parsed here will treat required and optional
-%% interchangeably. That is. only require that required/optional
-%% follow and preceed fixed, not that optional avps must follow
-%% required ones. We already have several specs for which this parsing
-%% is necessary and there seems to be no harm in accepting it.
-
-p_cmd("", Acc) ->
-    lists:reverse(Acc);
-
-p_cmd(Str, Acc) ->
-    {Next, Rest} = split_def(Str),
-    report(command, Next),
-    p_cmd(Rest, [p_cmd(Next) | Acc]).
-
-p_cmd("answer-message" ++ Str) ->
-    p_header([{name, 'answer-message'} | diameter_spec_scan:parse(Str)]);
-
-p_cmd(Str) ->
-    p_header(diameter_spec_scan:parse(Str)).
-
-%% p_header/1
-
-p_header(['<', {name, _} = N, '>' | Toks]) ->
-    p_header([N | Toks]);
-
-p_header([{name, 'answer-message' = N}, '::=',
-          '<', {name, "Diameter"}, {name, "Header"}, ':', {tag, code},
-          ',', {name, "ERR"}, '[', {name, "PXY"}, ']', '>'
-          | Toks]) ->
-    {N, -1, ['ERR', 'PXY'], [], parse_avps(Toks)};
-
-p_header([{name, Name}, '::=',
-          '<', {name, "Diameter"}, {name, "Header"}, ':', {number, Code}
-          | Toks]) ->
-    {Flags, Rest} = p_flags(Toks),
-    {ApplId, [C|_] = R} = p_appl(Rest),
-    '>' == C orelse ?ERROR({invalid_flag, {Name, Code, Flags, ApplId}, R}),
-    {?ATOM(Name), Code, Flags, ApplId, parse_avps(tl(R))};
-
-p_header(Toks) ->
-    ?ERROR({invalid_header, Toks}).
-
-%%   application-id   = 1*DIGIT
-%%
-%%   command-id       = 1*DIGIT
-%%                      ; The Command Code assigned to the command
-%%
-%%   r-bit            = ", REQ"
-%%                      ; If present, the 'R' bit in the Command
-%%                      ; Flags is set, indicating that the message
-%%                      ; is a request, as opposed to an answer.
-%%
-%%   p-bit            = ", PXY"
-%%                      ; If present, the 'P' bit in the Command
-%%                      ; Flags is set, indicating that the message
-%%                      ; is proxiable.
-%%
-%%   e-bit            = ", ERR"
-%%                      ; If present, the 'E' bit in the Command
-%%                      ; Flags is set, indicating that the answer
-%%                      ; message contains a Result-Code AVP in
-%%                      ; the "protocol error" class.
-
-p_flags(Toks) ->
-    lists:foldl(fun p_flags/2, {[], Toks}, ["REQ", "PXY", "ERR"]).
-
-p_flags(N, {Acc, [',', {name, N} | Toks]}) ->
-    {[?ATOM(N) | Acc], Toks};
-
-p_flags(_, T) ->
-    T.
-
-%% The RFC doesn't specify ',' before application-id but this seems a
-%% bit inconsistent. Accept a comma if it exists.
-p_appl([',', {number, I} | Toks]) ->
-    {[I], Toks};
-p_appl([{number, I} | Toks]) ->
-    {[I], Toks};
-p_appl(Toks) ->
-    {[], Toks}.
-
-%% parse_avps/1
-%%
-%% Output: list() of Avp | {Qual, Avp}
-%%
-%%         Qual = '*' | {Min, '*'} | {'*', Max} | {Min, Max}
-%%         Avp  = {'<', Name, '>'} | {Name} | [Name]
-%%
-%%         Min, Max = integer() >= 0
-
-parse_avps(Toks) ->
-    p_avps(Toks, ['<', '|', '<'], []).
-%% The list corresponds to the delimiters expected at the front, middle
-%% and back of the avp specification, '|' representing '{' and '['.
-
-%%   fixed            = [qual] "<" avp-spec ">"
-%%                      ; Defines the fixed position of an AVP
-%%
-%%   required         = [qual] "{" avp-spec "}"
-%%                      ; The AVP MUST be present and can appear
-%%                      ; anywhere in the message.
-%%
-%%   optional         = [qual] "[" avp-name "]"
-%%                      ; The avp-name in the 'optional' rule cannot
-%%                      ; evaluate to any AVP Name which is included
-%%                      ; in a fixed or required rule.  The AVP can
-%%                      ; appear anywhere in the message.
-%%
-%%   qual             = [min] "*" [max]
-%%                      ; See ABNF conventions, RFC 2234 Section 6.6.
-%%                      ; The absence of any qualifiers depends on whether
-%%                      ; it precedes a fixed, required, or optional
-%%                      ; rule.  If a fixed or required rule has no
-%%                      ; qualifier, then exactly one such AVP MUST
-%%                      ; be present.  If an optional rule has no
-%%                      ; qualifier, then 0 or 1 such AVP may be
-%%                      ; present.
-%%                      ;
-%%                      ; NOTE:  "[" and "]" have a different meaning
-%%                      ; than in ABNF (see the optional rule, above).
-%%                      ; These braces cannot be used to express
-%%                      ; optional fixed rules (such as an optional
-%%                      ; ICV at the end).  To do this, the convention
-%%                      ; is '0*1fixed'.
-%%
-%%   min              = 1*DIGIT
-%%                      ; The minimum number of times the element may
-%%                      ; be present.  The default value is zero.
-%%
-%%   max              = 1*DIGIT
-%%                      ; The maximum number of times the element may
-%%                      ; be present.  The default value is infinity.  A
-%%                      ; value of zero implies the AVP MUST NOT be
-%%                      ; present.
-%%
-%%   avp-spec         = diameter-name
-%%                      ; The avp-spec has to be an AVP Name, defined
-%%                      ; in the base or extended Diameter
-%%                      ; specifications.
-%%
-%%   avp-name         = avp-spec / "AVP"
-%%                      ; The string "AVP" stands for *any* arbitrary
-%%                      ; AVP Name, which does not conflict with the
-%%                      ; required or fixed position AVPs defined in
-%%                      ; the command code definition.
-%%
-
-p_avps([], _, Acc) ->
-    lists:reverse(Acc);
-
-p_avps(Toks, Delim, Acc) ->
-    {Qual, Rest} = p_qual(Toks),
-    {Avp, R, D} = p_avp(Rest, Delim),
-    T = if Qual == false ->
-                Avp;
-           true ->
-                {Qual, Avp}
-        end,
-    p_avps(R, D, [T | Acc]).
-
-p_qual([{number, Min}, '*', {number, Max} | Toks]) ->
-    {{Min, Max}, Toks};
-p_qual([{number, Min}, '*' = Max | Toks]) ->
-    {{Min, Max}, Toks};
-p_qual(['*' = Min, {number, Max} | Toks]) ->
-    {{Min, Max}, Toks};
-p_qual(['*' = Q | Toks]) ->
-    {Q, Toks};
-p_qual(Toks) ->
-    {false, Toks}.
-
-p_avp([B, {name, Name}, E | Toks], [_|_] = Delim) ->
-    {avp(B, ?ATOM(Name), E),
-     Toks,
-     delim(choose(B == '<', B, '|'), Delim)};
-p_avp(Toks, Delim) ->
-    ?ERROR({invalid_avp, Toks, Delim}).
-
-avp('<' = B, Name, '>' = E) ->
-    {B, Name, E};
-avp('{', Name, '}') ->
-    {Name};
-avp('[', Name, ']') ->
-    [Name];
-avp(B, Name, E) ->
-    ?ERROR({invalid_avp, B, Name, E}).
-
-delim(B, D) ->
-    if B == hd(D) -> D; true -> tl(D) end.
-
-%% split_def/1
-%%
-%% Strip one command definition off head of a string.
-
-split_def(Str) ->
-    sdh(Str, []).
-
-%% Look for the "::=" starting off the definition.
-sdh("", _) ->
-    ?ERROR({missing, '::='});
-sdh("::=" ++ Rest, Acc) ->
-    sdb(Rest, [$=,$:,$:|Acc]);
-sdh([C|Rest], Acc) ->
-    sdh(Rest, [C|Acc]).
-
-%% Look for the "::=" starting off the following definition.
-sdb("::=" ++ _ = Rest, Acc) ->
-    sdt(trim(Acc), Rest);
-sdb("" = Rest, Acc) ->
-    sd(Acc, Rest);
-sdb([C|Rest], Acc) ->
-    sdb(Rest, [C|Acc]).
-
-%% Put name characters of the subsequent specification back into Rest.
-sdt([C|Acc], Rest)
-  when C /= $\n, C /= $\s ->
-    sdt(Acc, [C|Rest]);
-
-sdt(Acc, Rest) ->
-    sd(Acc, Rest).
-
-sd(Acc, Rest) ->
-    {trim(lists:reverse(Acc)), Rest}.
-%% Note that Rest is already trimmed of leading space.
-
-%% ------------------------------------------------------------------------
-%% parse_groups/1
-%%
-%% Parse according to the ABNF for message specifications in 4.4 of
-%% RFC 3588 (shown below). Again, allow names starting with a digit
-%% and also require "AVP Header" without "-" since this is what
-%% the RFC uses in all examples.
-%%
-%% Output: list of {Name, Code, Vendor, Avps}
-%%
-%%         Name   = atom()
-%%         Code   = integer()
-%%         Vendor = [] | [integer()]
-%%         Avps   = see parse_avps/1
-
-parse_groups(Str) ->
-    p_group(trim(Str), []).
-
-%%      grouped-avp-def  = name "::=" avp
-%%
-%%      name-fmt         = ALPHA *(ALPHA / DIGIT / "-")
-%%
-%%      name             = name-fmt
-%%                         ; The name has to be the name of an AVP,
-%%                         ; defined in the base or extended Diameter
-%%                         ; specifications.
-%%
-%%      avp              = header  [ *fixed] [ *required] [ *optional]
-%%                         [ *fixed]
-%%
-%%      header           = "<" "AVP-Header:" avpcode [vendor] ">"
-%%
-%%      avpcode          = 1*DIGIT
-%%                         ; The AVP Code assigned to the Grouped AVP
-%%
-%%      vendor           = 1*DIGIT
-%%                         ; The Vendor-ID assigned to the Grouped AVP.
-%%                         ; If absent, the default value of zero is
-%%                         ; used.
-
-p_group("", Acc) ->
-    lists:reverse(Acc);
-
-p_group(Str, Acc) ->
-    {Next, Rest} = split_def(Str),
-    report(group, Next),
-    p_group(Rest, [p_group(diameter_spec_scan:parse(Next)) | Acc]).
-
-p_group([{name, Name}, '::=', '<', {name, "AVP"}, {name, "Header"},
-         ':', {number, Code}
-         | Toks]) ->
-    {Id, [C|_] = R} = p_vendor(Toks),
-    C == '>' orelse ?ERROR({invalid_group_header, R}),
-    {?ATOM(Name), Code, Id, parse_avps(tl(R))};
-
-p_group(Toks) ->
-    ?ERROR({invalid_group, Toks}).
-
-p_vendor([{number, I} | Toks]) ->
-    {[I], Toks};
-p_vendor(Toks) ->
-    {[], Toks}.
-
-%% ------------------------------------------------------------------------
-%% parse_avp_names/1
-
-parse_avp_names(Str) ->
-    [p_name(N) || N <- diameter_spec_scan:parse(Str)].
-
-p_name({name, N}) ->
-    ?ATOM(N);
-p_name(T) ->
-    ?ERROR({invalid_avp_name, T}).
-
-%% ------------------------------------------------------------------------
-%% parse_avp_types/1
-%%
-%% Output: list() of {Name, Code, Type, Flags, Encr}
-
-parse_avp_types(Str) ->
-    p_avp_types(Str, []).
-
-p_avp_types(Str, Acc) ->
-    p_type(diameter_spec_scan:split(Str, 3), Acc).
-
-p_type({[],[]}, Acc) ->
-    lists:reverse(Acc);
-
-p_type({[{name, Name}, {number, Code}, {name, Type}], Str}, Acc) ->
-    {Flags, Encr, Rest} = try
-                              p_avp_flags(trim(Str), [])
-                          catch
-                              throw: {?MODULE, Reason} ->
-                                  ?ERROR({invalid_avp_type, Reason})
-                          end,
-    p_avp_types(Rest, [{?ATOM(Name), Code, ?ATOM(type(Type)), Flags, Encr}
-                       | Acc]);
-
-p_type(T, _) ->
-    ?ERROR({invalid_avp_type, T}).
-
-p_avp_flags([C|Str], Acc)
-  when C == $M;
-       C == $P;
-       C == $V ->
-    p_avp_flags(Str, [?ATOM([C]) | Acc]);
-%% Could support lowercase here if there's a use for distinguishing
-%% between Must and Should in the future in deciding whether or not
-%% to set a flag.
-
-p_avp_flags([$-|Str], Acc) ->
-    %% Require encr on same line as flags if specified.
-    {H,T} = lists:splitwith(fun(C) -> C /= $\n end, Str),
-
-    {[{name, [$X|X]} | Toks], Rest} = diameter_spec_scan:split([$X|H], 2),
-
-    "" == X orelse throw({?MODULE, {invalid_avp_flag, Str}}),
-
-    Encr = case Toks of
-               [] ->
-                   "-";
-               [{_, E}] ->
-                   (E == "Y" orelse E == "N")
-                       orelse throw({?MODULE, {invalid_encr, E}}),
-                   E
-           end,
-
-    Flags = ordsets:from_list(lists:reverse(Acc)),
-
-    {Flags, ?ATOM(Encr), Rest ++ T};
-
-p_avp_flags(Str, Acc) ->
-    p_avp_flags([$-|Str], Acc).
-
-type("DiamIdent")   -> "DiameterIdentity";  %% RFC 3588
-type("DiamURI")     -> "DiameterURI";       %% RFC 3588
-type("IPFltrRule")  -> "IPFilterRule";      %% RFC 4005
-type("QoSFltrRule") -> "QoSFilterRule";     %% RFC 4005
-type(N)
-  when N == "OctetString";
-       N == "Integer32";
-       N == "Integer64";
-       N == "Unsigned32";
-       N == "Unsigned64";
-       N == "Float32";
-       N == "Float64";
-       N == "Grouped";
-       N == "Enumerated";
-       N == "Address";
-       N == "Time";
-       N == "UTF8String";
-       N == "DiameterIdentity";
-       N == "DiameterURI";
-       N == "IPFilterRule";
-       N == "QoSFilterRule" ->
-    N;
-type(N) ->
-    ?ERROR({invalid_avp_type, N}).
-
-%% ------------------------------------------------------------------------
-%% parse_commands/1
-
-parse_commands(Str) ->
-    p_abbr(diameter_spec_scan:parse(Str), []).
-
- p_abbr([{name, Name}, {name, Abbrev} | Toks], Acc)
-  when length(Abbrev) < length(Name) ->
-    p_abbr(Toks, [{?ATOM(Name), ?ATOM(Abbrev)} | Acc]);
-
-p_abbr([], Acc) ->
-    lists:reverse(Acc);
-
-p_abbr(T, _) ->
-    ?ERROR({invalid_command, T}).